POLYMERIC COMPOSITIONS AND ARTICLES PREPARED

THEREFROM

REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 60/969,824, filed on September 4, 2007, and fully incorporated herein by reference.

FIELD OF INVENTION

This invention provides compositions comprising ethylene/α-olefin interpolymers with improved dispersibility, particularly in soft, highly oil extended formulations, and for processes for detecting the same.

BACKGROUND OF THE INVENTION

Mixing advantages of gas phase polymerized EPDM are known. For example, see High Molecular Weight EPDM Via Metallocene Catalyst and Gas Phase Process, Vara, Rajan G; Daniel, Christian; Pillow, John, Rubber World (2004), 230(2), 27- 30. However, in the gas phase polymerization of EPDM, a periodic production of product has been found to disperse poorly in highly oil extended (soft) formulations (predominantly filler, oil and polymer). This poor dispersion results in small defect particles, which are visible on the surface of extruded profiles, and which renders such profiles unsuitable for applications, such as automotive weatherstrip, where aesthetics are especially important.

There is needed a method for analyzing a sample of particulate EPDM- containing carbon black to determine if the particles are likely to disperse well in soft, highly oil extended formulations. There is a further need for particulate EPDM containing carbon black, or other partitioning agents, especially high Mooney polymer, that has improved dispersion in soft, highly oil extended formulations, and which does not require, after polymerization, an additional compounding step to improve dispersion. These needs and others have been met by the following invention.

SUMMARY OF THE INVENTION

The invention provides a composition comprising at least one ethylene/α- olefin interpolymer, and at least one partitioning agent, and wherein the interpolymer optionally comprises at least one diene, and has a polymer Mooney Viscosity, ML(I +4) @ 125°C, greater than 150, and wherein the interpolymer is polymerized in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent, and wherein a -50/+70 mesh sieve fraction of the particles comprise a weight percentage of the partitioning agent that is less than Y, as determined by:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (50 and 70 mesh) converted into microns (254.5 microns), and B is from 76 to 81; and/or wherein a -70/+ 100 mesh sieve fraction of the particles comprise a weight percentage of the partitioning agent that is less than Y, as determined by:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (70 and 100 mesh) converted into microns (181 microns), and B is from 76 to 81; and/or wherein a -100/+ 140 mesh sieve fraction of the particles comprise a weight percentage of the partitioning agent that is less than Y, as determined by:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (100 and 140 mesh) converted into microns (128 microns), and B is from 76 to 81; and/or wherein a -140/+200 mesh sieve fraction of the particles comprise a weight percentage of the partitioning agent that is less than Y, as determined by:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (140 and 200 mesh) converted into microns (90.5 microns), and B is from 76 to 81; and/or wherein a -200/+270 mesh sieve fraction of the particles comprise a weight percentage of the partitioning agent that is less than Y, as determined by:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (200 and 270 mesh) converted into microns (64 microns), and B is from 76 to 81.

The invention also provides a process for determining whether a composition has good dispersibility, said composition comprising at least one ethylene/α-olefin interpolymer, and at least one partitioning agent, said process comprising:

A) polymerizing the interpolymer in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent;

B) separating the polymer particles into sized fractions; and

C) determining at least one of the following: i) the weight percent of partitioning agent (Ym) of a -50/+70 mesh sieve fraction of the particles, and determining Y from the equation:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (50 and 70 mesh) converted into microns (254.5 microns), and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility; and/or ii) the weight percent of partitioning agent (Ym) of a -70/+ 100 mesh sieve fraction of the particles, and determining Y from the equation:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (70 and 100 mesh) converted into microns (181 microns), and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility; and/or iii) the weight percent of partitioning agent (Ym) of a -100/+ 140 mesh sieve fraction of the particles, and determining Y from the equation:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (100 and 140 mesh) converted into microns (128 microns), and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility; and/or iv) the weight percent of partitioning agent (Ym) of a -140/+200 mesh sieve fraction of the particles, and determining Y from the equation:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (140 and 200 mesh) converted into microns (90.5 microns), and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility; and/or v) the weight percent of partitioning agent (Ym) of a -200/+270 mesh sieve fraction of the particles, and determining Y from the equation:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (200 and 270 mesh) converted into microns (64 microns), and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility.

The invention also provides a process for determining whether a composition has good dispersibility, said composition comprising at least one ethylene/α-olefin interpolymer, and at least one partitioning agent, said process comprising:

A) polymerizing the interpolymer in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent;

B) separating the polymer particles into sized fractions; and

C) determining the weight percent of partitioning agent (Ym) of at least one sieve fraction of the particles in the range from -100 and +270 mesh, and determining Y from the equation: by: Y = -0.1769X + B, wherein X is the average of the two sieve openings of the sieve fraction, expressed in microns, and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility.

The invention also provides a process for determining whether a composition has good dispersibility, said composition comprising at least one ethylene/α-olefin interpolymer, and at least one partitioning agent, said process comprising:

A) polymerizing the interpolymer in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent;

B) separating the polymer particles into sized fractions; and

C) determining the weight percent of partitioning agent (Ym) of at least one sieve fraction of the particles in the range from -100 and +270 mesh, and determining Y from the equation: Y = mX + B, wherein X is the average of the two sieve openings of the sieve fraction expressed in units of length, and the slope (m) and the intercept (B) are determined from a linear regression of a plot of the "critical concentration (upper limit) of the partitioning agent (in weight percent) for a specified dispersion rating," as a function of the average of two sieve openings of each sieve fraction from -100 to +270 mesh

expressed in units of length; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility; and wherein the specified dispersion rating is a numerical or categorical value that depicts the maximum level of visual defects allowed in a surface area of an extrudate formed from the composition.

The invention also provides a process for forming an extruded profile from a composition comprising at least one ethylene/α-olefin interpolymer, and at least one partitioning agent, said process comprising:

A) polymerizing the interpolymer in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent;

B) separating the polymer particles into sized fractions;

C) determining the weight percent of partitioning agent (Ym) of at least one sieve fraction of the particles in the range from -100 and +270 mesh, and determining Y from equation: Y = -0.1769X + B, wherein X is the average of the two sieve openings of the sieve fraction expressed in microns, and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility; and

D) forming an extruded profile from the composition, if the composition has a good dispersibility as determined in step C).

The invention also provides a process for forming an extruded profile from a composition comprising at least one ethylene/α-olefin interpolymer, and at least one partitioning agent, said process comprising:

A) polymerizing the interpolymer in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent;

B) separating the polymer particles into sized fractions; and

C) determining the weight percent of partitioning agent (Ym) of at least one sieve fraction of the particles in the range from -100 and +270 mesh, and determining Y from the equation: Y = mX + B, wherein X is the average of the two sieve openings of the sieve fraction expressed in units of length, and

the slope (m) and the intercept (B) are determined from a linear regression of a plot of the "critical concentration (upper limit) of the partitioning agent (in weight percent) for a specified dispersion rating," as a function of the average of two sieve openings of each sieve fraction from -100 to +270 mesh expressed in units of length; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility; and wherein the specified dispersion rating is a numerical or categorical value that depicts the maximum level of visual defects allowed in a surface area of an extrudate formed from the composition; and D) forming an extruded profile from the composition, if the composition has a good dispersibility as determined in step C).

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 depicts a comparison of the particle size and carbon black concentration (by TGA) in EPDM 46140 samples (Sample 1 was determined to have poor dispersion and Sample 2 was determined to have good dispersion by the dispersion test as described herein).

Figure 2 depicts a comparison of dispersion rating to carbon black concentration in -100/+140 mesh particles of EPDM 46140.

Figure 3 depicts a comparison of dispersion rating to carbon black concentration in -140/+200 mesh particles of EPDM 46140.

Figure 4 depicts a comparison of dispersion rating to carbon black concentration in -200/+270 mesh particles of EPDM 46140.

Figure 5 depicts a comparison of dispersion rating to carbon black concentration in -100/+140 mesh particles of EPDM 47085.

Figure 6 depicts a comparison of dispersion rating to carbon black concentration in -140/+200 mesh particles of EPDM 47085.

Figure 7 depicts a comparison of dispersion rating to carbon black concentration in -200/+270 mesh particles of EPDM 47085.

Figure 8 depicts the critical mean carbon black concentration (wt %) for EPDM 47085 and EPDM 46140 (determined from dispersion ratings and TGA carbon black analysis) on size fractions from various EPDM samples.

Figure 9 depicts the critical mean carbon black concentration (wt %) as a function of mean particle size (as indicated by mean or average sieve opening calculated from openings of the sieve through which a fraction is passed and the sieve on which the size fraction is collected).

Figure 10 depicts the dispersion rating versus "whole polymer" average carbon black content (from the "riffled sample muffle furnace method") on various EPDM 46140 samples.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides a composition comprising at least one ethylene/α- olefin interpolymer, and at least one partitioning agent, and wherein the interpolymer optionally comprises at least one diene, and has a polymer Mooney Viscosity, ML(I +4) @ 125°C, greater than 150, and wherein the interpolymer is polymerized in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent, and wherein a -50/+70 mesh sieve fraction of the particles comprise a weight percentage of the partitioning agent that is less than Y, as determined by:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (50 and 70 mesh) converted into microns (254.5 microns), and B is from 76 to 81; and/or wherein a -70/+ 100 mesh sieve fraction of the particles comprise a weight percentage of the partitioning agent that is less than Y, as determined by:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (70 and 100 mesh) converted into microns (181 microns), and B is from 76 to 81; and/or wherein a -100/+ 140 mesh sieve fraction of the particles comprise a weight percentage of the partitioning agent that is less than Y, as determined by:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (100 and 140 mesh) converted into microns (128 microns), and B is from 76 to 81; and/or

wherein a -140/+200 mesh sieve fraction of the particles comprise a weight percentage of the partitioning agent that is less than Y, as determined by:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (140 and 200 mesh) converted into microns (90.5 microns), and B is from 76 to 81; and/or wherein a -200/+270 mesh sieve fraction of the particles comprise a weight percentage of the partitioning agent that is less than Y, as determined by:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (200 and 270 mesh) converted into microns (64 microns), and B is from 76 to 81.

In one embodiment, B is 80.079. In another embodiment, B is 76.079. The invention also applies to compositions in which the interpolymer optionally comprises at least one diene, and has a polymer Mooney Viscosity, ML(I +4) @ 125°C, less than, or equal to, 150.

The interpolymer particles may be fractionated into the sieve fractions noted above using Sieve Method A or Sieve Method B, each as described herein.

As a result of polymerizing the interpolymer in the presence of the partitioning agent, the polymer particles formed, have a surface coating comprising the partitioning agent.

The weight percent of partitioning agent may by determined by TGA, Muffle Furnace test, or any other suitable analytical technique. The weight percentage is based on the total weight of the particle fraction examined.

In another embodiment, the interpolymer has a polymer Mooney viscosity, ML( 1+4) @ 125°C, greater than 155, or greater than 160, or greater than 170, or greater than 180.

In another embodiment, the interpolymer is an ethylene/α-olefin/diene interpolymer, and preferably an EPDM interpolymer.

In another embodiment, the at least one partitioning agent is selected from the group consisting of carbon black, silica and talc. In a preferred embodiment, the at least one partitioning agent is carbon black.

In another embodiment, the interpolymer is a homogeneously branched linear interpolymer or a homogeneously branched substantially linear interpolymer.

In another embodiment, the interpolymer is a homogeneously branched linear interpolymer.

In another embodiment, the interpolymer is a homogeneously branched substantially linear interpolymer.

In another embodiment, the interpolymer has a molecular weight distribution (Mw/Mn) less than 5, or less than 4, or less than 3.

In another embodiment, the interpolymer is formed in the presence of at least one single-site catalyst. In a further embodiment, the catalyst is a metallocene catalyst or a constrained geometry catalyst. In another embodiment, the catalyst is a metallocene catalyst. In another embodiment, the catalyst is a constrained geometry catalyst.

In another embodiment, the composition further comprises at least one oil or at least one plasticizer. In a further embodiment, the at least one oil or the at least one plasticizer is present in an amount less than 5 weight percent, based on the total weight of the composition.

In another embodiment, the composition further comprises at least one filler. In a further embodiment, the at least one filler is selected from the group consisting of carbon black; silica; clay; talc; titanium dioxide; silicates of aluminum, magnesium, calcium, sodium, potassium and mixtures thereof; carbonates of calcium, magnesium and mixtures thereof; oxides of silicon, calcium, zinc, iron, titanium, and aluminum; sulfates of calcium, barium, and lead; alumina trihydrate; magnesium hydroxide; and mixtures thereof. In another embodiment, the filler is selected from fiber glass; carbon fiber; wollastonite; MOS (Metal Oxy Sulfate); and combinations thereof.

In another embodiment, the composition further comprises at least one additive selected from the group consisting of pigments, antioxidants, flame retardants, scratch and mar resistant additives, and combinations thereof.

In another embodiment, the composition further comprises one or more other different olefin-based polymers. In another embodiment, the composition further comprises at least one propylene -based polymer.

In another embodiment, the composition further comprises at least one crosslinking agent. In a further embodiment, the composition is dynamically vulcanized.

An inventive composition may comprise a combination of two or more embodiments as described herein.

The invention also provides an article, comprising at least one component formed from an inventive composition.

In one embodiment, the article is an extruded profile. In another embodiment, the article is in an automotive part. In a further embodiment, the article is an automotive weather strip.

In another embodiment, the article is a tire. In another embodiment, the article is a belt or a hose. In another embodiment, the article is a building or construction material. In another embodiment, the article is a shoe component. In another embodiment, the article is a wire insulation or a cable insulation. In another embodiment, the article is a wire jacket or a cable jacket.

An inventive article may comprise a combination of two or more embodiments as described herein.

The invention also provides a thermoplastic vulcanizate (TPV) formed from an inventive composition. In a further embodiment, the TPV comprises at least one propylene-based polymer. In yet a further embodiment, the composition used to form the TPV comprises at least one crosslinking agent.

The invention also provides a thermoplastic olefin (TPO) formed from an inventive composition. In a further embodiment, the TPO comprises at least one propylene-based polymer.

The invention also provides a molded article comprising at least one component formed from an inventive composition, TPV or TPO.

The invention also provides a process for determining whether a composition has good dispersibility, said composition comprising at least one ethylene/α-olefin interpolymer, and at least one partitioning agent, said process comprising:

A) polymerizing the interpolymer in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent;

B) separating the polymer particles into sized fractions; and

C) determining at least one of the following: i) the weight percent of partitioning agent (Ym) of a -50/+70 mesh sieve fraction of the particles, and determining Y from the equation:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (50 and 70 mesh) converted into microns (254.5 microns), and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility (for example, a dispersion rating less than, or equal to, 30); and/or ii) the weight percent of partitioning agent (Ym) of a -70/+ 100 mesh sieve fraction of the particles, and determining Y from the equation:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (70 and 100 mesh) converted into microns (181 microns), and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility (for example, a dispersion rating less than, or equal to, 30); and/or iii) the weight percent of partitioning agent (Ym) of a -100/+ 140 mesh sieve fraction of the particles, and determining Y from the equation:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (100 and 140 mesh) converted into microns (128 microns), and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility (for example, a dispersion rating less than, or equal to, 30); and/or iv) the weight percent of partitioning agent (Ym) of a -140/+200 mesh sieve fraction of the particles, and determining Y from the equation:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (140 and 200 mesh) converted into microns (90.5 microns), and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility (for example, a dispersion rating less than, or equal to, 30); and/or v) the weight percent of partitioning agent (Ym) of a -200/+270 mesh sieve fraction of the particles, and determining Y from the equation:

Y = -0.1769X + B, wherein X is the average of the two sieve openings (200 and 270 mesh) converted into microns (64 microns), and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility (for example, a dispersion rating less than, or equal to, 30).

The invention also provides a process for determining whether a composition has good dispersibility, said composition comprising at least one ethylene/α-olefin interpolymer, and at least one partitioning agent, said process comprising:

A) polymerizing the interpolymer in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent;

B) separating the polymer particles into sized fractions; and

C) determining the weight percent of partitioning agent (Ym) of at least one sieve fraction of the particles in the range from -100 and +270 mesh, and determining Y from the equation: by: Y = -0.1769X + B, wherein X is the average of the two sieve openings of the sieve fraction, expressed in microns, and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility (for example, a dispersion rating less than, or equal to, 30).

The invention also provides a process for determining whether a composition has good dispersibility, said composition comprising at least one ethylene/α-olefin interpolymer, and at least one partitioning agent, said process comprising:

A) polymerizing the interpolymer in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent;

B) separating the polymer particles into sized fractions; and

C) determining the weight percent of partitioning agent (Ym) of at least one sieve fraction of the particles in the range from -100 and +270 mesh, and determining Y from the equation: by: Y = mX + B, wherein X is the average of the two sieve openings of the sieve fraction expressed in units of length (for example, microns, millimeters, mils, and preferably microns), and the slope (m) and the intercept (B) are determined from a linear regression of a plot of

the "critical concentration (upper limit) of the partitioning agent (in weight percent) for a specified dispersion rating," as a function of the average of two sieve openings of each sieve fraction from -100 to +270 mesh expressed in units of length; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility (for example, a dispersion rating less than, or equal to, the specified dispersion rating); and wherein the specified dispersion rating is a numerical or categorical value that depicts the maximum level of visual defects allowed in a surface area of an extrudate formed from the composition. In one embodiment, the extrudate is an extruded tape. In another embodiment, the surface area ranges from 0.5 cm ² to 10 cm ² . In another embodiment, the specified dispersion rating is the maximum number of visual defects allowed in a surface area of an extrudate formed from the composition

In another embodiment, specified dispersion rating is a numerical or categorical representation of the maximum level of visual defects allowed in a surface area of an extrudate formed from the composition.

A preferred dispersion rating system is a numerical count of the visible defects. However, other rating systems can be used. For example, a numerical scale that weights the defects by size could be used. An example of such a rating would be a defect rating that equals 1 times the number of defects under 50 microns in diameter plus 5 times the number of defects greater than 50 but less than 100 microns in diameter plus 10 times the number of defects greater than 100 microns in diameter. In addition, a rating could be based on optical density of a photograph or scanned image of the surface, preferably after an appropriate image enhancement to enhance the imaged defects using contrast, brightness threshholds and/or other image enhancement techniques known to the art. A rating could also be based on profilometry or other roughness measurement methods. A rating could be based on optical techniques that produce birefringence patterns or interferances as a function of thickness. A micro-spectroscopic mapping or nano-indentation mapping or atomic force microscope (tapping mode) mapping could also be used, although it is difficult,

with current technology, to map a large enough surface area with these microtechniques, such that the area is representative of the macroscale quality of the surface. Machine vision and computer imaging techniques may also be used to count defects, or develop size weighted measurements of the defect level and extent of degradation of surface aesthetic qualities. Any defect counting or rating technique that provides a scale of numerical or categorical (i.e., "bad", "poor", "fair", "good", "excellent") values may be used in this method. The scale may be binary ("good", "bad") or provide multiple discontinuous values (i.e., 1,2,3,4,5 or "bad", "poor", "fair", "good", "excellent") or continuous values (i.e., 0 through 100). The scale used should be able to differentiate between samples with "acceptable" and "unacceptable" surface defect levels such that a "maximum acceptable" rating can be identified. The rating system should depend primarily on the level of poorly dispersed particles, and should not be significantly affected by die lines or other types of surface imperfections that are not caused by poor particle dispersion.

The invention also provides a process for forming an extruded profile from a composition comprising at least one ethylene/α-olefin interpolymer, and at least one partitioning agent, said process comprising:

A) polymerizing the interpolymer in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent;

B) separating the polymer particles into sized fractions;

C) determining the weight percent of partitioning agent (Ym) of at least one sieve fraction of the particles in the range from -100 and +270 mesh, and determining Y from equation: Y = -0.1769X + B, wherein X is the average of the two sieve openings of the sieve fraction expressed in microns, and B is from 76 to 81; and if Ym is less than, or equal to, Y, then the composition has a good dispersibility (for example, a dispersion rating less than, or equal to, 30); and

D) forming an extruded profile from the composition, if the composition has a good dispersibility as determined in step C).

The invention also provides a process for forming an extruded profile from a composition comprising at least one ethylene/α-olefin interpolymer, and at least one partitioning agent, said process comprising:

A) polymerizing the interpolymer in the presence of the partitioning agent to form polymer particles having a surface coating comprising the partitioning agent;

B) separating the polymer particles into sized fractions; and

C) determining the weight percent of partitioning agent (Ym) of at least one sieve fraction of the particles in the range from -100 and +270 mesh, and determining Y from the equation: Y = mX + B, wherein X is the average of the two sieve openings of the sieve fraction expressed in units of length (for example, microns, millimeters, mils, and preferably microns), and the slope (m) and the intercept (B) are determined from a linear regression of a plot of the "critical concentration (upper limit) of the partitioning agent (in weight percent) for a specified dispersion rating," as a function of the average of two sieve openings of each sieve fraction from -100 to +270 mesh expressed in units of length (for example, microns, millimeters, mils, and preferably microns); and if Ym is less than, or equal to, Y, then the composition has a good dispersibility (for example, a dispersion rating less than, or equal to, the specified dispersion rating); and wherein the specified dispersion rating is a numerical or categorical value that depicts the maximum level of visual defects allowed in a surface area of an extrudate formed from the composition; and

D) forming an extruded profile from the composition, if the composition has a good dispersibility as determined in step C).

In one embodiment, the extrudate is an extruded tape.

In another embodiment, the surface area ranges from 0.5 cm ² to 10 cm ² .

In another embodiment, the specified dispersion rating is the maximum number of visual defects allowed in a surface area of an extrudate formed from the composition.

In another embodiment, specified dispersion rating is a numerical or categorical representation of the maximum level of visual defects allowed in a surface area of an extrudate formed from the composition.

A preferred dispersion rating system is a numerical count of the visible defects. However, other rating systems can be used. For example, a numerical scale that weights the defects by size could be used. An example of such a rating would be a defect rating that equals 1 times the number of defects under 50 microns in diameter, plus 5 times the number of defects greater than 50, but less than 100 microns in diameter, plus 10 times the number of defects greater than 100 microns in diameter. A rating could also be based on optical density of a photograph or scanned image of the surface, preferably after appropriate image enhancement to enhance the imaged defects through application of contrast, brightness threshholds and/or other image enhancement techniques known to the art. A rating could also be based on profilometry or other roughness measurement methods. A rating could also be based on optical techniques that produce birefringence patterns or interferances as a function of thickness. A micro-spectroscopic mapping or nano-indentation mapping or atomic force microscope (tapping mode) mapping could also be used, although it is difficult with current technology to map a large enough surface area, with these microtechniques, to be representative of the macroscale quality of the surface. Machine vision and computer imaging techniques may also be used to count defects, or develop size weighted measurements of the defect level and extent of degradation of surface aesthetic qualities. Any defect counting or rating technique that provides a scale of numerical or categorical (i.e., "bad", "poor", "fair", "good", "excellent") values may be used in this method. The scale may be binary ("good", "bad") or provide multiple discontinuous values (i.e., 1,2,3,4,5 or "bad", "poor", "fair", "good", "excellent") or continuous values (i.e., 0 through 100). The scale used should be able to differentiate between samples with "acceptable" and "unacceptable" surface defect levels such that a "maximum acceptable" rating can be identified. The rating system should depend primarily on the level of poorly dispersed particles and not be significantly affected by die lines, or other types of surface imperfections, that are not caused by poor particle dispersion.

For each inventive process, the interpolymer particles may be fractionated in to the sieve fractions noted above using Sieve Method A or Sieve Method B, each as described herein.

In one embodiment, B is 80.079. In another embodiment, B is 76.079.

As a result of polymerizing the interpolymer in the presence of the partitioning agent, the polymer particles formed, have a surface coating comprising the partitioning agent.

The weight percent of partitioning agent may by determined by TGA, Muffle Furnace test, or any other suitable analytical technique. The weight percentage is based on the total weight of the particle fraction examined.

In another embodiment, the interpolymer has a polymer Mooney Viscosity, ML(I +4) @ 125°C, greater than 150, or greater than 155, or greater than 160, or greater than 170, or greater than 180.

In another embodiment, the interpolymer has a polymer Mooney Viscosity, ML(I +4) @ 125°C, less than, or equal to, 155, or less than, or equal to 150, or less than, or equal to 140, or less than, or equal to 130.

In another embodiment, the interpolymer is an ethylene/α-olefin/diene interpolymer, and preferably an EPDM interpolymer.

In another embodiment, the at least one partitioning agent is selected from the group consisting of carbon black, silica and talc. In another embodiment, the at least one partitioning agent is carbon black.

In another embodiment, the interpolymer is a homogeneously branched linear interpolymer or a homogeneously branched substantially linear interpolymer. In another embodiment, the interpolymer is a homogeneously branched substantially linear interpolymer. In another embodiment, the interpolymer is a homogeneously branched linear interpolymer. In another embodiment, the interpolymer has a molecular weight distribution (Mw/Mn) less than 5, or less than 4, or less than 3.

In another embodiment, the interpolymer is formed in the presence of at least one single-site catalyst. In a further embodiment, the catalyst is a metallocene catalyst or a constrained geometry catalyst. In another embodiment, the catalyst is a

metallocene catalyst. In another embodiment, the catalyst is a constrained geometry catalyst.

An inventive process may comprise a combination of two or more embodiments as described herein.

For the inventive compositions and inventive processes described herein, the standard notation, -#/+#, for a sieve fraction (for example -50/+70) refers to the sieve mesh size (-#) through which the polymer particles pass through, and the sieve mesh size (+#) in which the polymer particles collect (do not pass through).

For the inventive compositions and inventive processes described herein, the average of each respective "two sieve openings" may be determined from the Wedco Corp., Particle Size Conversion Chart, American Slide-Chart Corp., Wheaton, IL, 1999. Relevant values from this slide-chart were transferred to the conversion chart (Table 1) provided below, and averages of each pair calculated. As shown in Table 1, the average of the two sieve openings is equated to the "approximate mean diameter in microns" of the fractionated particles. (The mean diameter of the +6 fraction assumes a maximum 0.5 inch diameter particle).

Averages for any other pair of sieve openings can be similarly calculated using their representative sieve openings expressed in units of length, such as microns. Table 1: Conversion of Sieve Fraction to Sieve Opening

Average of the two sieve openings.

Other mesh sizes fall within the scope of the invention. One skilled in the art can establish the relationships regarding content of partitioning agent and dispersibility using additional mesh sizes, as guided by the teachings of the present invention.

The dispersion of the interpolymer particles can be measured on any suitable extrudate, and preferably is measured on an extruded tape. For a dispersion test, the interpolymer particles may be formulated in any suitable manner, and preferably formulated as described in Table 2 below.

The dispersion can be rated by any numerical or categorical rating system that depicts the visual defect appearance of the extrudate surface. A preferred rating system is a numerical count of visual defects within a defined surface area.

In the equations for the weight percentage of the partitioning agent, Y, as described herein, the slope has a unit "wt % per unit length," and typically "weight percent per micron." The intercept, B, has a unit "wt%."

Ethylene/α-Olefin Interpolymer

The ethylene/α-olefin interpolymers of the present invention have polymerized therein ethylene, at least one α-olefin (for example, a C3-C20 α-olefin monomer), and optionally a diene (for example, a C4-C40 diene monomer). The α-olefin may be either an aliphatic or an aromatic compound, and may contain vinylic unsaturation or a cyclic compound, such as styrene, p-methyl styrene, cyclobutene, cyclopentene, and norbornene, including norbornene substituted in the 5 and 6 position with C1-C20 hydrocarbyl groups. The α-olefin is preferably a C3-C20 aliphatic compound, preferably a C3-C16 aliphatic compound, and more preferably a C3-C10 aliphatic compound. Preferred ethylenically unsaturated monomers include 4- vinylcyclohexene, vinylcyclohexane, and C3-C10 aliphatic α-olefins (especially propylene, isobutylene, 1-butene, 1-pentene, 1-hexene, 3 -methyl- 1-pentene, 4-methyl- 1-pentene, 1-octene, 1-decene and 1-dodecene). A more preferred C3-C10 aliphatic α-olefin is selected from the group consisting of propylene, 1-butene, 1-hexene and 1- octene, and more preferably propylene. In a preferred embodiment, the ethylene/α-

olefin interpolymer is an EPDM interpolymer. In a further embodiment, the diene is 5-ethylidene-2-norbornene (ENB).

In one embodiment, the ethylene/α-olefin interpolymer of the present invention has a C2 content of from 30 to 95 weight percent, more preferably from 50 to 95 weight percent, and most preferably from 55 to 95 weight percent, or from 60 to 95 weight percent, based on the total weight of polymerizable monomers. The interpolymers also contain at least one α-olefin, and preferably propylene, typically at a level of from 10 to 70 weight percent, more preferably from 10 to 50 weight percent, and most preferably from 10 to 45 weight percent, or 10 to 40 weight percent, based on the total weight of polymerizable monomers.

In another embodiment, the interpolymer contains a non-conjugated diene, and the non-conjugated diene content is preferably from 0.5 to 25 weight percent, more preferably from 1 to 20 weight percent, and most preferably from 2 to 15 weight percent, based on total weight of polymerizable monomers. In another embodiment, more than one diene may be incorporated simultaneously, for example 1 ,4-hexadiene and ENB, with total diene incorporation within the limits specified above.

In another embodiment, the diene monomer is desirably a non-conjugated diolefin that is conventionally used as a cure site for cross-linking. The nonconjugated diolefin can be a C6-C15 straight chain, branched chain or cyclic hydrocarbon diene. Illustrative nonconjugated dienes are straight chain acyclic dienes, such as 1 ,4-hexadiene and 1,5-heptadiene; branched chain acyclic dienes such as 5 -methyl- 1,4-hexadiene, 2-methyl-l,5-hexadiene, 6-methyl-l,5-heptadiene, 7- methyl-l,6-octadiene, 3,7-dimethyl-l,6-octadiene, 3,7-dimethyl-l,7-octadiene, 5,7- dimethyl-l,7-octadiene, 1 ,9-decadiene, and mixed isomers of dihydromyrcene; single ring alicyclic dienes such as 1 ,4-cyclohexadiene, 1,5-cyclooctadiene and 1,5- cyclododecadiene; multi-ring alicyclic fused and bridged ring dienes such as tetrahydroindene, methyl tetrahydroindene; alkenyl, alkylidene, cycloalkenyl and cycloalkylidene norbornenes such as 5-methylene-2-norbornene (MNB), 5- ethylidene-2-norbornene (ENB), 5-vinyl-2-norbornene, 5-propenyl-2-norbornene, 5- isopropylidene-2-norbornene, 5-(4-cyclopentenyl)-2-norbornene and 5- cyclohexylidene-2-norbornene. The diene is preferably a nonconjugated diene

selected from the group consisting of ENB, dicyclopentadiene, 1,4-hexadiene, 7- methyl-l,6-octadiene, and preferably, ENB, dicyclopentadiene and 1,4-hexadiene, more preferably ENB and dicyclopentadiene, and even more preferably ENB.

In another embodiment, the diene is a conjugated diene selected from the group consisting of 1,3-pentadiene, 1,3-butadiene, 2-methyl-l,3-butadiene, 4-methyl- 1,3-pentadiene, or 1,3-cyclopentadiene. The diene monomer content, whether it comprise a conjugated diene, a non-conjugated diene or both, may fall within the limits specified above for non-conjugated dienes.

Although preferred ethylene/α-olefin interpolymers are substantially free of any diene monomer that typically induces LCB, one may include such a monomer if costs are acceptable, and desirable interpolymer properties, such as, for example, processibility, tensile strength or elongation, do not degrade to an unacceptable level. Such diene monomers include dicyclopentadiene, NBD, methyl norbornadiene, vinyl- norbornene, 1 ,6-heptadiene, 1,7-octadiene, and 1 ,9-decadiene. In one embodiment, such monomers are added in an amount within a range of from greater than zero to 3 weight percent, more preferably from 0.01 to 2 weight percent, based on total weight of polymerizable monomers.

Preferred interpolymers of the present invention have polymerized therein ethylene, at least one α-olefin, and 5-ethylidene-2-norbornene (ENB). The α-olefin is preferably a C3-C20 aliphatic compound, more preferably a C3-C12 aliphatic compound, and even more preferably a C3-C8 aliphatic compound. Preferred α- olefins include propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-l- pentene, 4- methyl-1-pentene, 1-heptene, 1-octene, I-decene and 1-dodecene. More preferred α- olefins include propylene, 1-butene, 1-hexene and 1-octene, and most preferably propylene. In a preferred embodiment, the interpolymer has polymerized therein ethylene, propylene and 5-ethylidene-2-norbornene (ENB).

In another embodiment, the amount of ENB in the interpolymers of the invention is from 0.5 to 15 weight percent, preferably from 1 to 10 weight percent, and more preferably from 2 to 8 weight percent, based on the total weight of polymerizable monomers.

In general, polymerization may be accomplished at conditions well known in the art for Ziegler-Natta or Kaminsky-Sinn type polymerization reactions, that is, temperatures from O ⁰ C to 25O ⁰ C, preferably 3O ⁰ C to 200 ⁰ C, and pressures from atmospheric to 10,000 atmospheres. Polymerizations may also be conducted in accordance with processes disclosed in European Patent Application EP0775718A. This application and its cited references are fully incorporated herein by reference.

Polymerizations may be performed using a slurry, or gas phase polymerization, or combinations thereof. Preferably the polymerization is performed using a gas phase polymerization, and preferably in a gas phase reactor. Gas phase polymerizations are disclosed in European Patent Application EP0775718A. In another embodiment, a solution fed catalyst is used in a gas phase polymerization. In another embodiment, the catalyst is supported on a support, such as, silica, alumina, or a polymer (especially poly(tetrafluoroethylene) or a polyolefin), and may be spray dried onto such supports, and introduced in supported form into a polymerization reactor.

The polymerization may take place in any suitable type of reactor, and preferably a reactor design that would allow one skilled in the art to determine catalyst efficiency. Reactors include, but are not limited to, gas phase reactors, batch reactors, continuous reactors, pilot plant reactors, laboratory scale reactors, high throughput polymerization reactors, and other types of commercial reactors.

Polymerization is preferably by a single site catalyst (metallocene or constrained geometry catalyst), producing a low odor, relatively gel-free product as compared to a supported vanadium catalyzed EPDM made via the gas phase process (ElastoFlo Mega).

Suitable catalysts for use herein, preferably include constrained geometry catalysts, as disclosed in U.S. Patent Nos. 5,272,236 and 5,278,272, which are both fully incorporated herein by reference. The monocyclopentadienyl transition metal olefin polymerization catalysts taught in U.S. Patent No. 5,026,798, the teachings of which are incorporated herein by reference, are also suitable as catalysts of the invention.

The foregoing catalysts may be further described as comprising a metal coordination complex, comprising a metal of groups 3-10 or the Lanthanide series of the Periodic Table of the Elements, and a delocalized π- bonded moiety, substituted with a constrain-inducing moiety, said complex having a constrained geometry about the metal atom, such that the angle at the metal between the centroid of the delocalized, substituted π- bonded moiety, and the center of at least one remaining substituent, is less than such angle in a similar complex, containing a similar π- bonded moiety lacking in such constrain-inducing substituent. In addition, for such complexes comprising more than one delocalized, substituted x-bonded moiety, only one thereof, for each metal atom of the complex, is a cyclic, delocalized, substituted π- bonded moiety. The catalyst further comprises an activating cocatalyst.

Preferred catalyst complexes correspond to the Structure I:

Structure I .

In Structure I, M is a metal of group 3-10, or the Lanthanide series of the Periodic Table of the Elements, and preferably M is titanium, zirconium or hafnium;

Cp* is a cyclopentadienyl or substituted cyclopentadienyl group bound in an η5 bonding mode to M;

Z is a moiety comprising boron, or a member of group 14 of the Periodic Table of the Elements, and optionally sulfur or oxygen, said moiety having up to 20 non-hydrogen atoms, and optionally Cp* and Z together form a fused ring system;

X independently each occurrence is an anionic ligand group or neutral Lewis base ligand group having up to 30 non-hydrogen atoms; n is 0, 1, 2, 3, or 4 and is 2 less than the valence of M; and

Y is an anionic or nonanionic ligand group bonded to Z and M comprising nitrogen, phosphorus, oxygen or sulfur and having up to 20 non-hydrogen atoms, optionally Y and Z together form a fused ring system. More specific complexes are described in U.S. Patents 5,272,236 and 5,278,272, incorporated herein by reference.

Specific compounds include: (tert-butylamido) (tetramethyl-η5 - cyclopentadienyl)-l,2- ethanediylzirconium dichloride, (tert-butylamido)(tetramethyl- η 5 -cyclopentadienyl) 1,2-ethanediyltitanium dichloride, (methylamido)(tetramethyl- η5 - cyclopentadienyl)- 1 ,2-ethanediylzirconium dichloride, (methylamido) (tetramethyl-η5 cyclopentadienyl)- 1 ,2-ethanediyltitanium dichloride, (ethylamido)(tetramethyl-η5-cyclopentadienyl)-methylenetita nium dichloro, (tertbutylamido)dibenzyl(tetramethyl-η5 -cyclopentadienyl) silanezirconium dibenzyl, (benzylamido)dimethyl(tetramethyl-η5-cyclopentadienyl)silan etitanium dichloride, (phenylphosphido) dimethyl(tetramethyl η5-cyclopentadienyl)silanezirconium dibenzyl, (tertbutylamido)dimethyl(tetramethyl-η5 -cyclopentadienyl) silanetitanium dimethyl, and the like.

The complexes may be prepared by contacting a derivative of a metal, M, and a group I metal derivative or Grignard derivative of the cyclopentadienyl compound, in a solvent, and separating the salt byproduct. Suitable solvents for use in preparing the metal complexes are aliphatic or aromatic liquids, such as cyclohexane, methylcyclohexane, pentane, hexane, heptane, tetrahydrofuran, diethyl ether, benzene, toluene, xylene, ethylbenzene, etc., or mixtures thereof.

Suitable cocatalysts for use herein include polymeric or oligomeric aluminoxanes, especially methyl aluminoxane, as well as inert, compatible, noncoordinating, ion forming compounds. The so-called modified methyl aluminoxane (MMAO) is also suitable for use as a cocatalyst. One technique for preparing such modified aluminoxane is disclosed in U.S. Pat. No. 5,041,584, the teachings of which are incorporated herein by reference. Aluminoxanes can also be made, as disclosed in U.S. Patent Nos. 4,544,762; 5,015,749; and 5,041,585, the entire contents of each of which is incorporated herein by reference. Preferred cocatalysts are inert, noncoordinating, boron compounds, or aluminoxanes.

In addition to constrained geometry catalysts, additional single site catalyst systems that are suitable for use herein include metallocene catalyst systems and post metallocene catalyst systems.

Metallocene catalysts are, for example, coordination complexes between a transition metal, usually from group IV, in particular titanium, zirconium or hafnium,

and two optionally substituted cyclopentadienyl ligands. These catalysts are used in combination with a co-catalyst, for example an aluminoxane, preferably methylaluminoxane, or a boron compound (see, for example, Adv. Organomet. Chem, Vol. 18, p. 99, 10 (1980); Adv. Organomet. Chem, Vol. 32, p. 325, (1991); J.M.S.- Rev. Macromol. Chem. Phys., Vol. C34(3), pp. 439-514, (1994); J. Organometallic Chemistry, Vol. 479, pp. 1-29, (1994); Angew. Chem. Int., Ed. Engl., Vol. 34, p. 1143, (1995) Prog. Polym. ScL, Vol. 20, p. 459 15 (1995); Adv. Polym. ScL, Vol. 127, p. 144, (1997); U.S. Patent 5,229,478, or International applications WO 93/19107, EP 129 368, EP 277 003, EP 277 004, EP 632 065).

Preferably the partitioning agent is present in an amount of at least 10 weight percent on average in the whole distribution of particles, preferably in a core-shell morphology. Without filler, acting as partitioning agent, severe massing of low crystallinity grades of EPDM may occur during polymerization and/or storage, reducing the particulate nature of the product, which is preferred for mixing characteristics. The carbon black in the products of this invention is mostly distributed near the surfaces of particles ("core shell structure"), and not homogeneously throughout the particles, though a minor mass fraction of such particles may exist.

The ethylene/α-olefin interpolymers of the invention may be branched and/or unbranched interpolymers. The presence or absence of branching in the ethylene/α- olefin interpolymers, and if branching is present, the amount of branching, can vary widely, and may depend on the desired processing conditions and the desired polymer properties.

Preferred examples of suitable ethylene interpolymers for use in the invention include NORDEL™ MG polymers available from The Dow Chemical Company.

In another embodiment of the invention, the ethylene/α-olefin interpolymer has a molecular weight distribution (Mw/Mn) from 1.1 to 5, more preferably from 1.2 to 4 and most preferably from 1.5 to 3. All individual values and subranges from 1.1 to 5 are included herein and disclosed herein. In a preferred embodiment, the ethylene/α-olefin interpolymer is an ethylene/propylene/diene interpolymer.

In another embodiment, the ethylene/α-olefin interpolymer has a density from 0.81 to 0.96 g/cc, preferably from 0.82 to 0.95 g/cc, and more preferably from 0.83 to 0.94 g/cc (ASTM D-792-00). All individual values and subranges from 0.81 to 0.96 g/cc are included herein and disclosed herein. In another embodiment, the ethylene/α- olefin interpolymer has a density greater than, or equal to, 0.82 g/cc, preferably greater than, or equal to, 0.83 g/cc, and more preferably greater than, or equal to, 0.84 g/cc. In another embodiment, the ethylene/α-olefin interpolymer has a density less than, or equal to, 0.96 g/cc, preferably less than, or equal to, 0.94 g/cc, and more preferably less than, or equal to, 0.93 g/cc. In a preferred embodiment, the ethylene/α-olefin interpolymer is an ethylene/propylene/diene interpolymer.

In another embodiment, the ethylene/α-olefin interpolymer has a polymer Mooney Viscosity, ML(I +4) @ 125°C, greater than 150, or greater than 160, or greater than 170, or greater than 180, or greater than 200. In a preferred embodiment, the at least one ethylene/α-olefin interpolymer is an EPDM interpolymer. Polymer Mooney Viscosity refers to the viscosity of the "neat" polymer absent partitioning agent and oil.

In another embodiment, the ethylene/α-olefin interpolymer has a polymer Mooney Viscosity, ML(I +4) @ 125°C, greater than 60, or greater than 70, or greater than 80, or greater than 90, or greater than 100. In a preferred embodiment, the interpolymer is an EPDM interpolymer. In another embodiment, the ethylene/α- olefin interpolymer has a polymer Mooney Viscosity, ML(144) @ 125°C, from 60 to 200, or from 80 to 180, or from 100 to 160. In a preferred embodiment, the interpolymer is an EPDM interpolymer.

In another embodiment, the ethylene/α-olefin interpolymer has a polymer Mooney Viscosity, ML(14-4) @ 125°C, less than, or equal to, 150, or less than, or equal to 140, or less than, or equal to 130, or less than, or equal to 120, or less than, or equal to 100. In a preferred embodiment, the interpolymer is an EPDM interpolymer.

In another embodiment, the ethylene/α-olefin interpolymer is a homogeneously branched linear or homogeneously branched substantially linear ethylene/α-olefin interpolymer. In a preferred embodiment, the ethylene/α-olefin interpolymer is an ethylene/propylene/diene interpolymer.

The terms "homogeneous" and "homogeneously-branched" are used in reference to an ethylene/α-olefin interpolymer, in which the comonomer(s) is randomly distributed within a given polymer molecule, and all of the polymer molecules have the same or substantially the same ethylene-to-comonomer(s) ratio. The homogeneously branched ethylene interpolymers include linear ethylene interpolymers, and substantially linear ethylene interpolymers.

Included amongst the homogeneously branched linear ethylene interpolymers are ethylene interpolymers, which lack long chain branching (or measurable amounts of long chain branching), but do have short chain branches, derived from the comonomer polymerized into the interpolymer, and which are homogeneously distributed, both within the same polymer chain, and between different polymer chains. That is, homogeneously branched linear ethylene interpolymers lack long chain branching, just as is the case for the linear low density polyethylene polymers or linear high density polyethylene polymers, made using uniform branching distribution polymerization processes, as described, for example, by Elston in U.S. Patent 3,645,992.

Substantially linear ethylene interpolymers are described in U.S. Patent Nos. 5,272,236 and 5,278,272; the entire contents of each are herein incorporated by reference. As discussed above, the substantially linear ethylene interpolymers are those in which the comonomer is randomly distributed within a given interpolymer molecule, and in which substantially all of the interpolymer molecules have the same or substantially the same ethylene/comonomer ratio within that interpolymer. Substantially linear ethylene interpolymers are prepared using a constrained geometry catalyst. Examples of constrained geometry catalysts, and such preparations, are described in U.S Patent Nos. 5,272,236 and 5,278,272.

In addition, the substantially linear ethylene interpolymers are homogeneously branched ethylene polymers having long chain branching. The long chain branches have about the same comonomer distribution as the polymer backbone, and can have about the same length as the length of the polymer backbone. The "substantially linear," typically, is in reference to a polymer that is substituted, on average, with 0.01 long chain branches per 1000 carbons to 3 long chain branches per 1000 carbons.

The substantially linear ethylene interpolymers form a unique class of homogeneously branched ethylene polymers. They differ substantially from the well- known class of conventional, homogeneously branched linear ethylene interpolymers, described by Elston in U.S. Patent 3,645,992, and, moreover, they are not in the same class as conventional heterogeneous "Ziegler-Natta catalyst polymerized" linear ethylene polymers (for example, ultra low density polyethylene (ULDPE), linear low density polyethylene (LLDPE) or high density polyethylene (HDPE), made, for example, using the technique disclosed by Anderson et al., in U.S. Patent 4,076,698); nor are they in the same class as high pressure, free-radical initiated, highly branched polyethylenes, such as, for example, low density polyethylene (LDPE), ethylene- acrylic acid (EAA) copolymers and ethylene vinyl acetate (EVA) copolymers.

Additives

Optional additives include, but are not limited to, one or more oils and one or more plasticizers. Plasticizers include, but are not limited to, petroleum oils such as ASTM D2226 aromatic oils; paraffinic and naphthenic oils; polyalkylbenzene oils; organic acid monoesters such as alkyl and alkoxyalkyl oleates and stearates; organic acid diesters such as dialkyl, dialkoxyalkyl, and alkyl aryl phthalates, terephthalates, sebacates, adipates, and glutarates; glycol diesters such as tri-, tetra-, and polyethylene glycol dialkanoates; trialkyl trimellitates; trialkyl, trialkoxyalkyl, alkyl diaryl, and triaryl phosphates; chlorinated paraffin oils; coumarone-indene resins; pine tars; vegetable oils such as castor, tall, rapeseed, and soybean oils and esters and epoxidized derivatives thereof; esters of dibasic acids (or their anhydrides) with monohydric alcohols such as o-phthalates, adipates and benzoates; and the like. Additional examples of suitable oils include those listed as ester plasticizers in Ellul, U.S. Patent 6,326,426, which is incorporated herein. An artisan skilled in the processing of elastomers and TPV compositions will recognize which type of oil will be most beneficial.

A variety of additional additives may be used in compositions of this invention. The additives include, but are not limited to, antioxidants; surface tension modifiers; anti-block agents; lubricants; processing oils, crosslinking agents,

dispersants, blowing agents, UV stabilizers, antimicrobial agents such as organometallics, isothiazolones, organosulfurs and mercaptans; antioxidants such as phenolics, secondary amines, phosphites and thioesters; antistatic agents such as quaternary ammonium compounds, amines, and ethoxylated, propoxylated or glycerol compounds; fillers and reinforcing agents such as carbon black, glass, metal carbonates such as calcium carbonate, metal sulfates such as calcium sulfate, talc, clay or graphite fibers; hydrolytic stabilizers; lubricants such as fatty acids, fatty alcohols, esters, fatty amides, metallic stearates, paraffinic and microcrystalline waxes, silicones and orthophosphoric acid esters; acid neutralizers or halogen scavengers such as zinc oxide; mold release agents such as fine-particle or powdered solids, soaps, waxes, silicones, polyglycols and complex esters such as trimethylol propane tristearate or pentaerythritol tetrastearate; pigments, dyes and colorants; heat stabilizers such as organotin mercaptides, an octyl ester of thioglycolic acid and a barium or cadmium carboxylate; ultraviolet light stabilizers such as a hindered amine, an o-hydroxy-phenylbenzotriazole, a 2- hydroxy-4-alkoxybenzophenone, a salicylate, a cyanoacrylate, a nickel chelate and a benzylidene malonate and oxalanilide; acid- scavengers; and zeolites, molecular sieves and other known deodorizers. Other additives include scratch/mar additives, such as polydimethyl siloxane (PDMS) or functionalized polydimethyl siloxane or IRGASURF® SR 100 (available from Ciba Specialty Chemicals) or scratch mar formulations containing erucamide. Functionalized polydimethyl siloxanes include, but are not limited to, hydroxyl functionalized polydimethyl siloxane, amine functionalized polydimethyl siloxane, vinyl functionalized polydimethyl siloxane, aryl functionalized polydimethyl siloxane, alkyl functionalized polydimethyl siloxane, carboxyl functionalized polydimethyl siloxane, mercaptan functionalized polydimethyl siloxane, and derivatives of the same. One skilled in the art can readily determine quantities of additives needed based on the application involved.

Antioxidants and antiozonants additives for use in the invention include hindered phenols, bisphenols, and thiobisphenols; substituted hydroquinones; tris(alkylphenyl)phosphites ; dialkylthiodipropionates ; phenylnaphthylamines ; substituted diphenylamines; dialkyl, alkyl aryl, and diaryl substituted p-phenylene

diamines; monomeric and polymeric dihydroquinolines; 2-(4-hydroxy-3,5-t- butylaniline)-4,6-bis(octylthio)l,3,5-triazine, hexahydro-l,3,5-tris-β-(3,5-di-t-butyl-4- hydroxyphenyl)propionyl-s-triazine, 2,4,6-tris(n- 1 ,4-dimethylpentylpphenylene- diamino)-l,3,5-triazine, tris-(3,5-di-t-butyl-4-hydroxybenzyl)isocyanurate, nickel dibutyldithiocarbamate, 2-mercaptotolylimidazole and its zinc salt, petroleum waxes, and the like.

Other optional additives for use in the invention include activators (metal oxides such as zinc, calcium, magnesium, cadmium, and lead oxides; fatty acids such as stearic, lauric, oleic, behenic, and palmitic acids and zinc, copper, cadmium, and lead salts thereof; di-, tri-, and polyethylene glycols; and triethanolamine); accelerators (sulfenamides such as benzothiazoles, including bis-benzothiazoles, and thiocarbamyl sulfenamides, thiazoles, dithiocarbamates, dithiophosphates, thiurams, guanidines, xanthates, thioureas, and mixtures thereof); tackifiers (rosins and rosin acids, hydrocarbon resins, aromatic indene resins, phenolic methylene donor resins, phenolic thermosetting resins, resorcenol-formaldehyde resins, and alkyl phenol formaldehyde resins such as octylphenol-formaldehyde resin); homogenizing agents, peptizers, pigments, flame retardants, fungicides, and the like. In one embodiment, the total amount of optional ingredients ranges from about 40 to 800 parts by weight based upon 100 parts of the elastomers in the composition.

An inventive composition may further comprise one or more thermoplastic polymers, including, but not limited to, homopolymers and interpolymers of propylene. The propylene-based interpolymers may contain about 1 to 20 percent by weight of ethylene or an α-olefin comonomer of 4 to 16 carbon atoms, or mixtures thereof. Examples of α-olefins include butene, pentene, hexene, octene, and 4- methyl-1-pentene copolymers. Additionally, the propylene-based polymers may comprise one or more polar monomers, such as maleic acid esters, acrylic acid esters or methacrylic acid esters. The propylene-based polymers may be prepared by typical Ziegler-Natta or metallocene catalysts. In one embodiment, suitable thermoplastic polymers comprise crystalline, high molecular weight solid products from the polymerization of one or more monoolefins, by either high pressure or low pressure processes. Examples of such polymers are the isotactic and syndiotactic monoolefin

polymers, representative members of which are commercially available. Commercially available thermoplastic polymers, preferably polyethylene or polypropylene homopolymers or copolymers, may be advantageously used in the practice of the invention, with polypropylene homopolymers and copolymers being preferred.

The thermoplastic polymers also include polyethylenes and their related copolymers such as butene, propylene, hexene, octene, 4-methyl-l-pentene copolymers; functional grades of polyethylenes such as maleic acid esters, acrylic and methacrylic acid esters, acrylonitrile, vinyl acetate, and derivatives such as chlorinated and sulfonated polyethylenes and copolymers; ionomers; polyvinyl chlorides and their related copolymers, functional and modified grades; polymers of acetal and their related copolymers and modified grades; fluorinated olefin polymers; polyvinylidene fluoride; polyvinyl fluoride; polyamides and their modified grades; polyimides; polyarylates; polycarbonates and their related copolymers and modified grades; poly ethers; poly ethersulf ones; polyarylsulphones; polyketones; polyetherimides; poly( 4-methyl-l-pentene); polypheny lenes and modified grades; polysulphones; polyurethanes and their related modified grades; polyesters and their related modified grades; polystyrene and their related copolymers and modified grades; polybutylene; polymers of acrylo-nitrile, polyacrylates, mixtures thereof, and the like.

Suitable thermoplastic polymers include high density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), very low density polyethylene (VLDPE), ultra low density polyethylene (ULDPE), homogeneously branched linear ethylene/α-olefin interpolymers and homogeneously branched substantially linear ethylene/α-olefin interpolymers. An inventive composition may also comprise one or more or more unsaturated diene elastomers (e.g., BR, SBR, NR and IR).

An inventive composition may also comprise one or more vulcanizing agents. Vulcanizing agents include, but are not limited to, vulcanizing materials or curatives which do not require the addition of a curing or vulcanizing activator. The vulcanizing agent also includes a vulcanizing material or curative which requires the

addition of a cure activator or vulcanizing activator to the vulcanizing material. If a vulcanizing agent is used, which requires the further addition of a vulcanizing or cure activator, either the cure activator or the vulcanizing agent, or both, can be encapsulated. Typically, when an encapsulated cure system is used, a vulcanizing agent which requires the addition of a cure activator or vulcanizing activator is used.

Any suitable vulcanizing agent, or combination of vulcanizing agents, may be used in the practice of this invention. Examples of suitable vulcanizing agents are accelerated sulfur systems, including efficient and semi-efficient systems; peroxide systems, alone or with co-agents; phenolic resin curative systems; phenylenebismaleimide; urethane curatives; grafted alkoxysilanes; hydrosilylation curatives; and diamine curatives.

A preferred class of vulcanizing agents is the phenolic curatives. These curatives include, but are not limited to, phenolic curing resin made by condensation of halogen substituted phenol, Ci-Cio alkyl substituted phenol (preferably substituted in the para position), or non-substituted phenol with an aldehyde (preferably formaldehyde) in an alkaline medium or by condensation of bi-functional phenol dialcohols. Dimethylol phenols substituted with C ₅ -C ₁₀ alkyl in the para-position can be used. Halogenated alkyl substituted phenol curing resins prepared by halogenation of alkyl-substituted phenol curing resins also can be used. Phenolic curing systems may comprise methylol phenolic resins with or without activator such as halogen donor and metal compound. Details of this are described in Giller, U.S. Pat. No. 3,287,440 and Gerstin et al, U.S. Pat. No. 3,709,840. Non-halogenated phenolic curing resins may be used in conjunction with halogen donors, preferably along with a hydrogen halide scavenger. Sometimes, halogenated, preferably brominated, phenolic resins containing 2 to 10 weight percent bromine are used in conjunction with a hydrogen halide scavenger such as metal oxides, for example, iron oxide, titanium oxide, magnesium oxide, magnesium silicate, silicon dioxide, and preferably zinc oxide. The presence of metal oxide and halogen donor singly or together promote the crosslinking function of the phenolic resin. The preparation of halogenated phenolic resin and their use in a curative system comprising zinc oxide are described in U. S. Pat. Nos. 2,972,600 and 3,093,613, the disclosure of which is incorporated herein by

reference. Preferred phenolic curing resins contain between about 5-15 weight percent methylol groups. A suitable phenolic curative comprises a non-halogenated dimethylol phenolic resin and zinc oxide.

Suitable phenolic resin curatives are commercially available under the trade name SP-1045 (octylphenol/formaldehyde heat reactive resin), SP-1055, and SP-1056 (brominated octylphenol/formaldehyde heat reactive resins) and are available from Schenectady International, Inc. of New York.

Conventional sulfur curative systems are also suitable as cure systems for the compositions and TPVs of this invention, either with a sulfur vulcanizing agent alone, or with sulfur and a vulcanization accelerator.

The sulfur donor curative systems suitable in the practice of the invention comprise conventional sulfur donor vulcanizing agents. Suitable sulfur donors include alkyl polysulfides, thiuram disulfides, and amine polysulfides. Examples of suitable sulfur donors are 4,4'-dithiomorpholine, dithiodiphosphorodisulfides, diethyldithiophosphate polysulfide, alkyl phenol disulfide, and tetramethylthiuram disulfide. The sulfur-donors may be used with conventional sulfur-vulcanizing accelerators, for example, thiazole accelerators, such as benzothiazyl disulfide, N- cyclohexyl-2-benzothiazolesulfenamide, 2-mercaptobenzothiazole, N-tert-butyl-2- benzothiazolesulfenamide, 2-benzothiazyl-N,N-diethylthiocarbamyl sulfide, 2- (morpholinodithio)benzothiazole, and N,N- dimorpholinodithiocarbamate. Accelerators such as dithiocarbamates or thiurams and thioureas can be included in these sulfur cures, which also normally include zinc oxide.

Examples of vulcanizing activators include halogen donors and metal halide activators, such as stannous chloride (anhydrous or hydrated), ferric chloride, zinc chloride, or halogen donating polymers such as chlorinated paraffin, chlorinated polyethylene, chlorosulfonated polyethylene, and polychlorobutadiene. The term "activator," as used herein, means any material which materially increases the crosslinking efficiency of the vulcanizing agent or curative, and includes metal oxides and halogen donors, used alone or conjointly.

The skilled artisan will be able to readily determine a sufficient or effective amount of vulcanizing agent, and if necessary, vulcanizing activator to be employed

without undue calculation or experimentation. The amount of vulcanizing agent should be sufficient to at least partially vulcanize the elastomeric polymer. In one embodiment, the amount of vulcanizing agent comprises from about 1 to about 20 parts by weight, more preferably from about 3 to about 16 parts by weight, and even more preferably from about 4 to about 12 parts by weight, vulcanizing agent per hundred parts by weight ethylene/α-olefin interpolymer (phr).

Additional vulcanizing agents for use in the invention include sulfur containing compounds such as elemental sulfur, 4,4'-dithiodimorpholine, thiuram di- and polysulfides, alkylphenol disulfides, and 2-morpholino-dithiobenzothiazole; peroxides such as di-tertbutyl peroxide, tertbutylcumyl peroxide, dicumyl peroxide, 2,5dimethyl-2,5-di-(tertbutylperoxy) hexane, di-(tertbutylperoxyisopropyl) benzene, tertbutyl peroxybenzoate and l,l-di-(tertbutylperoxy)-3,3,5-trimethylcyclohexane; metal oxides such as zinc, magnesium, and lead oxides; dinitroso compounds such as p-quinone dioxime and p,p'-dibenzoylquinone-dioxime; and phenol-formaldehyde resins containing hydroxymethyl or halomethyl functional groups. Sulfur can be a crystalline elemental sulfur or an amorphous elemental sulfur, and either type can be in pure form or supported on an inert carrier. An example of a supported sulfur is Rhenogran S-80 (80% S and 20% inert carrier) from Rhein Chemie.

Suitable coagents for use with peroxides include, but are not limited to, triallyl cyanurate (TAC), difunctional methacrylates (e.g., SARET SR516HP from Sartomer Corp.), trifunctional methacrylates (e.g., SARET SR517HP from Sartomer Corp.), metallic monomers including zinc diacrylate (SARET SR633), zinc dimethacrylate (SARET SR634) and the like.

The suitability of any of these vulcanizing agents for use in the invention will be largely governed by the choice of elastomers, as is well known to those skilled in the compounding art. The amount of the vulcanizing agent can range from about 1 to 10 parts by weight based upon 100 parts of the elastomers in the composition. Vulcanization temperatures and time employed are typical, for example, temperatures ranging from about 25O ⁰ F to about 44O ⁰ F, and times ranging from about 1 minute to about 120 minutes.

In another embodiment, an inventive composition may comprise one or more flame retardants, including, but not limited to, a metal hydrate, such as aluminum trihydroxide, magnesium dihydroxide, or combinations thereof. In a further embodiment, the flame retardant is a metal hydrate and present in an amount from 25 weight percent to 75 weight percent, based on the total weight of the composition. In another embodiment, the surface of the metal hydroxide may be coated with one or more materials, including silanes, titanates, zirconates, carboxylic acids, and maleic anhydride-grafted polymers. In another embodiment, the average particle size of the metal hydrate may range from less than 0.1 micrometers to 50 micrometers. In some cases, it may be desirable to use a metal hydroxide having a nano-scale particle size. The metal hydroxide may be naturally occurring or synthetic. The flame-retardant composition may contain other flame-retardant additives. Other suitable non- halogenated flame retardant additives include calcium carbonated, I red phosphorus, silica, alumina, titanium oxides, talc, clay, organo-modified clay, zinc t borate, antimony trioxide, wollastonite, mica, magadiite, organo-modified magadiite, silicone polymers, phosphate esters, hindered amine stabilizers, ammonium octamolybdate, intumescent compounds, and expandable graphite. Suitable halogenated flame retardant additives include decabromodiphenyl oxide, decabromodiphenyl ethane, ethylene-big (tetrabromophthalimide), and 1,4,7, 10-dimethanodibenzo(a,e)- cyclooctene, 1,2,3, 4,7,8,9,10,13, 13, 14,14-dodecachloro l,4,4a,5,6,7,10,10a,l l,12,12a-dodecahydro-. A further description of such flame retardants is found in International Publication No. WO 2005/023924, fully incorporated herein by reference.

In another embodiment, the inventive compositions contain a compatibilizing amount of a flame retardant package, which includes a halogenated alkane flame retardant, an aromatic halogenated flame retardant, and optionally a flame retardant synergist. In a further embodiment, the alkane flame retardant is selected from hexahalocyclododecane; tetrabromocyclooctane; pentabromochlorocyclohexane; 1,2- dibromo-4-(l,2-dibromoethyl)cyclohexane; 1, 1,1,3-tetrabromononane; or a combination thereof. In another embodiment, the aromatic halogenated flame retardant comprises one or more of hexahalodiphenyl ethers; octahalodiphenyl ethers;

decahalodiphenyl ethers; decahalobiphenyl. ethanes; 1, 2-bis(trihalophenoxy) ethanes; l,2-bis(pentahalophenoxy) ethanes; a tetrahalobisphenol-A; ethylene(N, N')-bis- tetrahalophtlialimides; tetrabromobisphenol-A bis (2,3-dibromopropyl ether; tetrahalophthalic anhydrides; hexahalobenzenes; halogenated indanes; halogenated phosphate esters; halogenated polystyrenes; polymers of halogenated bisphenol-A and epichlorohydrin; or a combination thereof. In yet another embodiment, the flame retardant synergist comprises one or more of a metal oxide, halogenated paraffin, triphenylphosphate, dimethyldiphenylbutane, polycumyl, or a combination thereof.

In another embodiment, the composition contains from about 0.5 to about 8 parts by weight halogenated alkane flame retardant; from about 0.5 to about 8 parts by weight aromatic halogenated flame retardant; from 0 to about 6 parts by weight flame retardant synergist, all based on the total weight of the composition. A further description of such flame retardants is found in International Publication No. WO 2002/12377, fully incorporated herein by reference.

An inventive composition may comprise one or more fillers. Fillers include, but are not limited to, carbon black; silicates of aluminum, magnesium, calcium, sodium, potassium and mixtures thereof; carbonates of calcium, magnesium and mixtures thereof; oxides of silicon, calcium, zinc, iron, titanium, and aluminum; sulfates of calcium, barium, and lead; alumina trihydrate; magnesium hydroxide; phenol-formaldehyde, polystyrene, and poly(alphamethyl)-styrene resins, natural fibers, synthetic fibers, and the like.

Applications

The compositions of the present invention may be used in a variety of articles or their component parts or portions. For purposes of illustration only, and not by way of limitation, such articles may be selected from extruded parts, extruded profiles, automotive parts, adhesives, belts, hoses, tubes, gaskets, membranes, molded goods, tires or tire sidewalls.

Additional articles that contain at least one component formed from the compositions of the invention include, but are not limited to, polymer films, fabric coated sheets, polymer sheets, foams, tubing, fibers, coatings, automotive parts, such

as automotive weatherstrip, instrument panels, automotive interior skins, bumpers, automotive fascia, automotive boots, tires and tire components, wire and cable jacketing, wire and cable insulation, hose, mining and conveyor belts, computer parts, building materials, household appliances, electrical supply housings, trash cans, storage or packaging containers, lawn furniture strips or webbing, lawn mower, garden hose, and other garden appliance parts, refrigerator gaskets, acoustic systems, utility cart parts, desk edging, toys and water craft parts, artificial leather and artificial turf. The compositions can also be used in roofing applications such as roofing membranes. The compositions can further be used in fabricating components of footwear, such as a shaft for a boot, particularly an industrial work boot. A skilled artisan can readily augment this list without undue experimentation.

Articles can be prepared by injection molding, extrusion, extrusion followed by either male or female thermoforming, low pressure molding, calendaring, compression molding, fiber spinning, and other melt processes.

Specially formulated vulcanizable compositions of the invention can be extruded through a die to produce elastomeric articles, such as strip stock for the tread, sidewall, and bead filler components of a pneumatic tire, or used to produce sheet stock for the air retention innerliner. Other specially formulated elastomeric inventive compositions can be calendered onto textile or steel cord fabric to produce cord-reinforced sheet stock for the carcass and circumferential belt components of the tire.

The vulcanizable elastomeric compositions can be shaped and vulcanized into an elastomeric article or body. The elastomeric bodies can be readily co-cured. Accordingly, the present invention includes a process for interfacial co-curing of shaped elastomeric bodies in mutual contact. The process comprises (i) forming the vulcanizable elastomeric compound into a shaped elastomeric body; (ii) assembling the shaped elastomeric body, so that it contacts another shaped elastomeric body comprising a major portion of a highly unsaturated rubber to produce an assembly; and (iii) vulcanizing the assembly under conditions, so as to effect substantial crosslinking across an interface between the shaped elastomeric bodies.

As discussed above, the compositions of the invention can be used to form thermoplastic olefins (TPOs). TPO 's are generally produced by dispersing one or more elastomeric polymers, such as ethylene/α-olefin/diene interpolymers, in one or more thermoplastic matrix polymers, such as a propylene-based polymers. In one embodiment, the TPO is formed from a composition comprising at least one propylene-based polymer, and at least one ethylene-based polymer as the elastomer/rubber. In a further embodiment, the composition comprises a filler. Common fillers include talc, fiberglass, carbon fiber, wollastonite, and MOS (Metal Oxy Sulfate). Common elastomers/rubbers include EPR (ethylene-propylene rubber), EPDM (EP-diene rubber), EO (ethylene-octene), EB (ethylene-butadiene), SEBS (Styrene-ethylene-butadiene-styrene). In another embodiment, the TPO comprises some fraction of PP (polypropylene), PE (polyethylene), BCPP (block copolymer polypropylene), elastomer/rubber, and a filler.

The components of a TPO are typically blended together at 210 - 27O ⁰ C, under high shear. A twin screw extruder or a continuous mixer may be employed to achieve a continuous stream, or a Banbury® compounder may be employed for batch production. A higher degree of mixing and dispersion is achieved in the batch process, but the superheated batch must immediately be processed through an extruder to be pelletized into a transportable intermediate.

The properties of a TPO product depend greatly upon controlling the size and distribution of the microstructure. The thermoplastic component(s) of a blend constitute the "crystalline phase", and the elastomers/rubbers give the "amorphous phase." If thermoplastic component(s) is/are the dominant component of a TPO blend, then the elastomeric/rubber fraction will be dispersed into a continuous matrix of "crystalline" thermoplastic (example, one or more propylene-based polymers); these TPO's are referred to as "hard TPO's." If the fraction of elastomers/rubbers is greater than 40 weight percent, phase inversion may be possible when the blend cools, resulting in an amorphous continuous phase, and a crystalline dispersed phase. This type of material is non-rigid, and is sometimes called TPR for ThermoPlastic Rubber, or "soft TPO." In hard TPO's, if the rubber phase is too large, physical properties and aesthetics are adversely affected. For TPOs, it is preferred that the elastomers/rubbers

are well-dispersed, and elastomer/rubber phases are preferably less than 10 micron in size, more preferably less than 5 micron in size, and even more preferably less than 1 micron in size.

TPO can be processed by injection molding, profile extrusion, and thermoforming. TPOs are used extensively in the automotive industry, but also in roofing and other outdoor applications where its UV stability is advantageous.

As discussed above, the compositions of the invention can be used to form thermoplastic vulcanizates (TPVs). TPVs are generally produced by dynamic vulcanization of one or more elastomeric polymers, such as ethylene/α-olefin/diene interpolymers, in a thermoplastic matrix polymer, such as one or more propylene- based polymers. Generally, a thermoplastic polymer and elastomer should be intimately melt mixed prior to vulcanization as discussed in CP. Rader and S. Abdou- Sabet, "Two-phase elastomer alloys," in S. K. De and A.K. Bhowmick, eds., "Thermoplastic Elastomers from Rubber-Plastic Blends," Ellis Horwood, New York, 1990, pp 159-197 and US 4,311,628; Bhowmick A.K. and Inoue T., Journal of Applied Polymer Science, Vol. 49 (1993) page 1893. During dynamic vulcanization, the elastomer is converted to a crosslinked material dispersed as small particles in a continuous thermoplastic matrix. The result is a useful composition or TPV having the melt processability of thermoplastics combined with the rubber-like properties of crosslinked elastomers, including elastic recovery, heat resistance, compression set resistance, and softness.

Thermoplastic Vulcanizates (TPVs) are similar to TPOs, except that, as discussed above, the elastomer phase is crosslinked during mixing, a process called "dynamic vulcanization." Dynamic vulcanization results in small crosslinked elastomer phases dispersed in a thermoplastic matrix. A typical example is crosslinked EPDM in an isotactic PP matrix. Because the elastomer is crosslinked, the elastomer fraction can exceed the approximately 40 weight percent limit noted above for TPO's and still maintain the thermoplastic as the continuous phase. As with TPOs, the TPVs physical properties depend strongly on the size of the dispersed phase crosslinked elastomer, with sizes less than 10 microns preferred (A. Y. Coran and R. Patel, Rubber Chem. Technol., 53, 141 (1980)). Because of the high amount

of elastomer possible in these blends, and the ability to use a crystalline thermoplastic polymer matrix, high oil concentrations can be used in TPVs. This improves processability, reduces cost and gives excellent low temperature properties and low modulus (soft). For TPVs, it is preferred that the elastomer/rubber be well-dispersed, and elastomer/rubber phases are preferably less than 10 micron in size, more preferably less than 5 micron in size, and even more preferably less than 1 micron in size.

In one embodiment, the TPV is formed from a composition comprising at least one propylene-based polymer, at least one ethylene-based polymer as the elastomer/rubber, and at least one crosslinking agent. In a further embodiment, the composition comprises a filler. Common fillers include talc, fiberglass, carbon fiber, wollastonite, and MOS(Metal Oxy Sulfate). Common elastomers/rubbers include EPR (ethylene-propylene rubber), EPDM (EP-diene rubber), EO (ethylene-octene), EB (ethylene-butadiene), SEBS (Styrene-ethylene-butadiene-styrene). In another embodiment, the TPV composition further comprises an oil or a plasticizer.

TPVs are noted for their combination of thermoplastic processability (suitable for extrusion, injection molding, etc.) and thermoset rubber-like physical properties (compression set resistance, tensile properties). They are also noted for oil resistance (when a crystalline polymer like polypropylene is the matrix), and for excellent cyclic fatigue resistance. TPVs are used in many of the same applications as TPOs, but where higher temperature resistance or softer materials (such as in grips) are required.

Examples of TPO compositions and/or TPV compositions can be found in U.S. Patent Nos. 6,548,600 and 6,680,361; and in International Publication No. WO 2006/022666.

DEFINITIONS

Any numerical range recited herein, includes all values from the lower value and the upper value, in increments of one unit, provided that there is a separation of at least two units between any lower value and any higher value. As an example, if it is stated that a compositional, physical or other property, such as, for example, molecular weight, melt index, etc., is from 100 to 1,000, it is intended that all

individual values, such as 100, 101, 102, etc., and sub ranges, such as 100 to 144, 155 to 170, 197 to 200, etc., are expressly enumerated in this specification. For ranges containing values which are less than one, or containing fractional numbers greater than one (e.g., 1.1, 1.5, etc.), one unit is considered to be 0.0001, 0.001, 0.01 or 0.1, as appropriate. For ranges containing single digit numbers less than ten (e.g., 1 to 5), one unit is typically considered to be 0.1. These are only examples of what is specifically intended, and all possible combinations of numerical values between the lowest value and the highest value enumerated, are to be considered to be expressly stated in this application. Numerical ranges have been recited, as discussed herein, in reference to density, Mooney Viscosity, component amounts, and other properties.

The term "composition," as used herein, includes a mixture of materials which comprise the composition, as well as reaction products and decomposition products formed from the materials of the composition.

The term "polymer," as used herein, refers to a polymeric compound prepared by polymerizing monomers, whether of the same or a different type. The generic term polymer thus embraces the term homopolymer, usually employed to refer to polymers prepared from only one type of monomer, and the term interpolymer as defined hereinafter.

The term "interpolymer," as used herein, refers to polymers prepared by the polymerization of at least two different types of monomers. The generic term interpolymer thus includes copolymers, usually employed to refer to polymers prepared from two different types of monomers, and polymers prepared from more than two different types of monomers.

The term, "olefin-based polymer," as used herein, refers to a polymer that comprises more than 50 mole percent polymerized olefin monomer, for example ethylene or propylene (based on the total amount of polymerizable monomers), and optionally may comprise one or more comonomers.

The term, "ethylene-based polymer," as used herein, refers to a polymer that comprises more than 50 mole percent polymerized ethylene monomer (based on the total amount of polymerizable monomers), and optionally may comprise one or more comonomers.

The term, "propylene-based polymer," as used herein, refers to a polymer that comprises more than 50 mole percent polymerized propylene monomer (based on the total amount of polymerizable monomers), and optionally may comprise one or more comonomers.

The terms "blend" or "polymer blend," as used herein, mean a blend of two or more polymers. Such a blend may or may not be miscible (not phase separated at molecular level). Such a blend may or may not be phase separated. Such a blend may or may not contain one or more domain configurations, as determined from transmission electron spectroscopy, light scattering, x-ray scattering, and other methods known in the art.

As discussed above, the standard notation, -#/+#, for a sieve fraction (for example -50/+70) refers to the sieve mesh size (-#, for example -50) through which the polymer particles pass through, and the sieve mesh size (+#, for example +70) in which the polymer particles collect (do not pass through).

The phrase "critical concentration of partitioning agent," and similar phrases, as used herein, refer to the upper limit for the concentration (typically in weight percent) of a partitioning agent that is required for a specified dispersion rating. The amount of partitioning agent may be determined by thermogravimetric analysis, a muffle furnace test, or any other suitable technique known in the art. The amount of partitioning agent is based on the total weight of the particles examined.

The phrase "dispersion rating less than, or equal to, 30," as used herein, is in reference to the dispersion test described below. Other dispersion tests can be used in the invention. One skilled in the art can develop the equations for critical amounts of partitioning agent as a function of sieve fraction using the teachings of the present invention.

MEASUREMENTS

Isolation of Particle Fractions by Sieving

Sieve Method A: Particles were sieved by passing the particles through a sieve, stack with the following mesh sizes (US Standard Certified Test Sieve sizes): 6, 12, 40, 100, 140, 200, 270 (a pan was located under the 270 sieve). Each sieve had

an eight inch diameter, and half height sieves were employed. A Tyler RX-812 shaker was used to hold and shake the sieve stack. Typically 100 grams of the particles, were charged to the stack, and a 30 minute shake interval employed. The - 100/+140 (106/150 μm sieve screen openings), -140/+200 (75/106 μm sieve screen openings), and -200/+270 (53/75 μm sieve screen openings) size fractions were individually collected, and assayed for carbon black content by TGA, after the manner described below (the Muffle Furnace Test or other analytical techniques may also be used to determine the content of the partitioning agent).

Sieve Method B: Particles were sieved by passing the particles through a sieve, stack with the following mesh sizes (US Standard Certified Test Sieve sizes): 6, 8, 12, 16, 20, 30, 40, 50, 70, 100, 140, 200, 270 (a pan was located under the 270 sieve). Each sieve had an eight inch diameter, and half height sieves were employed. A Tyler RX-812 shaker was used to hold and shake the sieve stack. Typically 100 grams of particles were charged to the stack, and a 30 minute shake interval employed. The -50/+70 (212/297 μm sieve screen openings), -70/+ 100 (150/212 μm sieve screen openings) -100/+140 (106/150 μm sieve screen openings), -140/+200 (75/106 μm sieve screen openings), and -200/+270 (53/75 μm sieve screen openings) size fractions were individually collected, and assayed by TGA after the manner described below (the Muffle Furnace Test or other analytical techniques may also be used to determine the content of the partitioning agent).

Particle Size Conversion Chart

As discussed above, the average of each respective "two sieve openings" may be determined from the Wedco Corp., Particle Size Conversion Chart, American Slide-Chart Corp., Wheaton, IL, 1999. Portions of this chart are provided below in the first two columns of Table IA. As shown in Table IA, the average of the two sieve openings is equated to the "approximate mean diameter in microns" of the fractionated particles.

Table IA

*Average of the two sieve openings.

TGA

Thermal gravimetric analysis (TGA) was performed using a TA Instruments Model TGA 2950, operated with a 10°C/minute heating rate. Polymer sample (30-60 mg) was loaded into the TGA sample holder. For each analysis, a nitrogen environment was maintained until 52O ⁰ C. At 52O ⁰ C, the environment was changed to air, until 800 ⁰ C. The weight loss between approximately 52O ⁰ C and 800 ⁰ C was attributed to carbon black, with the weight at 800 ⁰ C due to ash from catalyst residues in the polymer and inorganics in the carbon black. The percent weight loss between 520 and 800 ⁰ C was taken as the measured percent carbon black (Ym) in the sample.

Muffle Furnace Test

This gravimetric determination involves direct pyrolysis of a melt-massed sample in a muffle furnace at 800 ⁰ C.

Apparatus:

Balance accurate to 0.000 Ig.

Retsch/Brinkman Sample Divider Model PTlOOO (riffler) equipped with a Model DR 100 vibratory feeder, eight 500 mL jars and a 99 minute digital timer.

Brabender prep mixer.

Brabender prep mill.

Muffle furnace. Procedure:

The polymer sample was riffled into equal portions using the riffler ("riffled sample muffle furnace method"), or individual sieve fractions were prepared by sieving through an appropriate sieve stack.

Sample Melt- Mixing - The temperatures on both zones of the Prep Mixer were set at 70 ⁰ C ± 2°C. The mixing speed on the prep mixer was set to 20 rpm. The sample was inserted into the prep mixer, the ram was lowered, and the mix speed was increased to 50 rpm. The sample was mixed for 6 minutes, or until the stock temperature reached 160 ⁰ C ± 2°C. The mixing was then stopped, and the sample was removed from the prep mixer. The mixed material was placed on the prep roll mill equilibrated at 7O ⁰ C + 5 ⁰ C, and 10-20 RPM (roll nip opening should be 2.5 ± 0.2 mm). The material was rolled into a tightly-rolled stock, and passed endwise through the mill again. This process was repeated two more times, for a total of three end- passes of tightly-rolled stock. After the last pass, the sample material was collected in the form of a flat sheet or "blanket." The milled sample sheet was placed on a clean, flat, and dry metal surface for cooling to ambient temperature.

Sample Analysis:

A clean, empty crucible and lid was weighed to the nearest 0.0001 gram, and the weight recorded. The milled sample (2.0 ± 0.5 grams) was finely cut, and placed in the crucible, and the filled crucible was then covered with the crucible lid, and the weight of the crucible assembly measured to the nearest 0.0001 gram, and recorded. The crucible assembly was carefully placed in the muffle furnace (the muffle furnace door remained shut during testing). The crucible was thermally treated for 6-7

minutes to effectively pyrolyze the milled sample, without burning off the sample. Next, the crucible assembly was removed from the muffle furnace and transferred to an air-purged desiccator for cooling. After a minimum of 6-8 minutes of cooling, the crucible assembly was weighed to the nearest 0.0001 gram, and this weight recorded. The weight percent of carbon black in the milled sample was determined from the recorded weights.

Weight crucible and lid (C3) = weight in grams of sample crucible and lid Weight sample added to crucible (C4) = sample polymer weight Weight of crucible, lid and ash (C5) = final ashing weight Weight % carbon black (C6) = (C5 - C3)/C4 * 100

Weight % oil and combustible additives in sample (C7) can be obtained from process mass flow rates or by other methods known to those skilled in the art. For example, the weight percent oil can be determined from mass balance in the production plant. For example, it can be determined from the rate of oil feed into the process, divided by the rate of total product output.

Phr oil and combustible additives in sample (C8) = C7/(100 - C7 - C6) * 100 Phr carbon black in sample, base polymer (C9) = C6/(100 - C6 - Cl) * 100 If the weight percent oil and combustible additives is low (less than 5 weight percent), an approximate conversion of carbon black phr values to weight percent carbon black is C9/(100+C9). This method of converting reported carbon black concentrations (phr) to weight percent was used for Figure 10.

Dispersion Test (Reference Example)

A standardized "dispersion test" was applied to all the polymer samples included in this study. This test utilized a tangential mixer, and the run conditions and formula, as shown in Table 2, to produce a soft compound or formulation. This compound was milled into sheet, then extruded into a tape, which was visually inspected for undispersed particle defects on the tape surface. Each tape appeared fairly uniform in surface appearance. The number of such defects in a surface area of 4 cm ² (a random, visually representative area) was visually counted, and reported as the "dispersion rating" for that sample. Counting was stopped at 100, so a dispersion

rating reported as 100, refers to 100 or more defects. A dispersion rating of 30 was the upper limit of acceptability, and provided an extrusion profile with acceptable surface quality.

Table 2: Dispersion Test Conditions and Formulation

Dispersion test (high i filled compound with C Black)

Nordel MG 130

Black - Spheron 5000A 195

CaCO3 - Omya BSH 60

Talc - Mistron vapor RP6 20

Paraffin. Oil - Sunpar 120 150

Stearic acid 1

Sulphur 0 25

Total (phr) 556 25

Ratio Filler/oil (weigth) 1 83

Internal Mixing, gel test methoc i (DDE)

Mixer : Tangential 9 2 litres from Werner & Pfleiderer

Fill factor : 65%

Chamber anc rotors are heated up at respectively 90 and 60 °C

Upside down method - Ram cleaning after 120s

Dump temp 13O ⁰ C

Dump time seconds 180"

Typical compound viscosity (NDR ₄ 61 ₄ 0 01 )

Mooney Viscosity ML 1 + ₄ mιnutes at 100 ^s C (ISO 289-1 :1994)

Final 73

Slope -0 33

Equipment:

Laboratory internal mixer (Tangential rotors - W&P of 9.2 litres), equipped with a heating unit.

Roll mill (suited to the size of the mixer)

Extruder (60 mm screw diameter; L/D = 1:10 to 16, low shear)

Die with opening of (1 x 30) mm.

Conditions at the internal mixer

Load factor: underloading of 5 to 10% (65% load factor for this mixer) Start temperatures: chamber 90 ⁰ C, rotor 60 ⁰ C Rotor speed: 40 min ^"1

Mixing procedure: An upside-down mixing procedure was used, whereby fillers, oil, and stearic acid were added to the mixer, and mixed for a total of one minute with the ram up. Then, the polymer was added, and the ram lowered, mixing for three minutes for a total mixing time of four minutes. Halfway through the mixing process (i.e., after two minutes), the ram was raised and cleaned. The sample was dropped from the mixer when the temperature reached between 120 and 14O ⁰ C, or five minutes, whichever end point came first (the time to reach the drop temperature depends on the Mooney Viscosity of the polymer).

Mill mixing procedure

The compound is banded on the mill, and cut six times from each side on the mill (nip 4 - 8 mm, 30 ⁰ C - 50 ⁰ C). The compound was removed from the mill in the form of a thick sheet (blanket). The compound was maintained at room temperature for 30 min to 2 hours prior to extrusion.

Extrusion conditions

Screw temperature: 6O ⁰ C

Feeding zone temperature and extrusion barrel temperature: 70 ⁰ C to 8O ⁰ C

Die temperature: 90 ⁰ C

Screw speed: 10 min ^"1

Extrusion speed: variable

Extrusion procedure

Strips cut from the milled sheet were fed into the extruder, and the first 500 g of exrudate was disregarded (2 first minutes of extrusion). Then, three strips of extrudate tape with a length of approximately 0.75 m were cut and examined for defects. The examination and rating count was done within a 24 hours.

Determination of the "rating count"

A surface area of approximately 2 cm x 2 cm was defined for examination. All defects, visible to the naked eye, were counted. The final rating represented the final

number of defects detected on a surface of 4 cm ² . The number was rounded to a multiple of 5.

Mooney Viscosity

For a carbon black coated ethylene/α-olefin interpolymer (preferably an EPDM) interpolymer, the polymer Mooney Viscosity [MV (ML1+4 at 125 ⁰ C)] for the interpolymer (no carbon black and no oil) can be determined, by one skilled in the art, by one of two methods as described below. The following methods are in reference to carbon black coated interpolymers, however, one skilled in the art could use similar methods for other types of fillers. One skilled in the art could also use similar methods for interpolymer containing significant amounts of oil (for example, greater than 2 weight percent oil, based on the weight of the interpolymer). The instrument is an Alpha Technologies Rheometer MV 2000. Polymer Mooney Viscosity refers to the Mooney Viscosity of the interpolymer without any carbon black and without any oil.

Method 1

For a carbon black coated interpolymer, with no oil or less than 2 weight percent oil (known amount, and based on the weight of the interpolymer) (INT A), and which has a measured viscosity less than 100 [MV (ML1+4 at 125 ⁰ C)] as determined by ASTM D 1646-06 (Alpha Technologies Rheometer MV 2000), the polymer Mooney viscosity of the interpolymer can be determined from a calibration curve as follows. The amount of carbon black in the polymerized INT A interpolymer can be determined gravimetrically by selective ashing of the polymer in a manner to leave the carbon black intact.

An interpolymer, corresponding in chemical make-up to the interpolymer of interest, and prepared from the same or similar catalyst system, and of known polymer Mooney Viscosity [MV (ML1+4 at 125 ⁰ C)], is melt blended with various levels of carbon black, and no oil or less than 2 wt% oil, to form a range of carbon black filled interpolymers. Melt blending can be done in a Brabender mixer. The

carbon black and oil used, are the same as that in the interpolymer of interest (INT A). The Mooney viscosity [MV (ML1+4 at 125 ⁰ C)] is measured for each sample (ASTM D1646-06, Alpha Technologies Rheometer MV 2000), and a calibration curve is generated, showing the measured Mooney Viscosity as a function of amount of carbon black. A series of such calibration curves are generated for several interpolymers (no filler, no or little oil) of varying viscosities. The data from the generated calibration curves are entered into a regression program, such as a MICROSOFT EXCEL regression program, and the following information is generated: a coefficient for the carbon black level, a coefficient for the measured Mooney viscosity, and an intercept.

The polymer Mooney Viscosity [MV (ML1+4 at 125 ⁰ C)] of the interpolymer (INT A) can be calculated using the data generated from the regression analysis, the known level of carbon black in the interpolymer (INTA), and the measured Mooney viscosity [MV (ML1+4 at 125 ⁰ C)] of the interpolymer (INT A).

Method 2

For a carbon black coated interpolymer, with no oil or less than 2 weight percent oil (known amount and based on the weight of the interpolymer) (INT B), and which has a measured viscosity greater than, or equal to, 100 [MV (ML1+4 at 125 ⁰ C)], as determined by ASTM D 1646-06 (Alpha Technologies Rheometer MV 2000), the measured Mooney viscosity can be determined from a calibration curve as follows. The amount of carbon black in the polymerized INT B interpolymer can be determined gravimetrically by selective ashing of the polymer in a manner to leave the carbon black intact.

An interpolymer, corresponding in chemical make-up to the interpolymer of interest, and prepared from the same or similar catalyst system, and of known polymer Mooney Viscosity, is melt blended with a fixed amount of carbon black (for example, from 40 to 60 phr carbon black, based on hundred parts interpolymer), and a fixed amount of an oil (for example, from 60 to 80 phr oil, based on hundred parts interpolymer) to form a first sample. The carbon black and oil are the same as that in the interpolymer of interest (INTB). Additional samples are formed, each having an

interpolymer of different Mooney viscosity, and each having the same amount of both carbon black and oil. The Mooney viscosity [MV (ML1+4 at 125 ⁰ C)] is measured for each sample (ASTM D 1646-06 (Alpha Technologies Rheometer MV 2000)). A calibration curve is generated, showing the measured Mooney viscosity [MV (ML1+4 at 125 ⁰ C)] as a function of the polymer Mooney Viscosity [MV (ML1+4 at 125 ⁰ C)] of the interpolymer.

The carbon-black coated interpolymer (INT B) of interest is next compounded with additional carbon black to achieve a final carbon black level as that used in the samples for calibration, as discussed above. Also the INT B interpolymer is compounded with the same oil, and at the same oil level, as that used in the samples for calibration as discussed above, to form a "modified INT B" interpolymer. The Mooney viscosity [MV (ML1+4 at 125 ⁰ C)] of the modified INT B interpolymer is measured. The polymer Mooney Viscosity of the interpolymer can be then calculated using the calibration curve as described above.

Gel Permeation Chromatography

The average molecular weights and molecular weight distributions for ethylene/α-olefin interpolymers can be determined with a gel permeation chromatographic system, consisting of a Polymer Laboratories Model 200 series, high temperature chromatograph, equipped with differential viscometer and differential refractometer detectors. The column and carousel compartments are operated at 14O ⁰ C for ethylene-based polymers. The columns are three Polymer Laboratories 10- micron Mixed-B columns. The solvent is 1,2,4 trichlorobenzene. The samples are prepared at a concentration of 0.1 gram of polymer in 50 milliliters of solvent and filtered through divided volcanic glass to remove carbon black. The solvent, used as the mobile phase, and to prepare the samples, contains 200 ppm of butylated hydroxytoluene (BHT). Ethylene-base polymers are prepared by agitating lightly for two hours at 14O ⁰ C. The injection volume is 100 microliters, and the flow rate is 1.0 milliliters/minute. Calibration of the GPC column set is performed with narrow molecular weight distribution polystyrene standards, purchased from Polymer Laboratories (UK), with molecular weights ranging from 580 to 8,400,000, and using

a universal calibration. Universal calibration molecular weight calculations are performed using Viscotek TriSEC software Version 3.0.

The following examples illustrate, but do not, either explicitly or by implication, limit the present invention. Unless otherwise indicated, all parts and percentages are by weight.

EXPERIMENTAL

EPDM 46140 (MV(l+4) @ 125°C of 140) and EPDM 47085 (MVQ+4) @ 125°C of 85), gas phase polymerized EPDM' s, each made via a constrained geometry catalyst in the presence of carbon black, were produced in a fluidized bed gas phase reactor. Samples of each were evaluated for dispersion in a soft compound (or formulation), by measuring gels or undispersed products in an extruded tape. This traditional approach to measuring gels or undispersed products is labor intensive, requires access to mixing and extrusion equipment, and requires several hours to run. A dispersion rating of "30" (30 defects per 4 square centimeters) was determined to be the transition point between "acceptable" and "unacceptable" levels of surface defects. Acceptable surface defect levels had a dispersion rating of 30 or less.

EPDM samples were sieved and analyzed by TGA method for carbon black content. Three sieve fractions (-100/+140, -140/+200, -200/+270 mesh, corresponding to the sieve pair through which particles of a given fraction passed and were trapped on, were analyzed for carbon black content. A comparison of the carbon black content of several sieved fractions of two 46140 EPDM samples is shown in Figure 1. As seen in this figure, particles of smaller sieved fractions have a greater weight percentage of carbon black, based on the total weight of the particles in the sieved fraction.

Figure 1 also shows the carbon black "concentration difference" between "good (sample 2)" and "poor (sample 1)" dispersion samples increased with decreasing particle size up to approximately 140 to 200 mesh. Thus, a preferable range of sizes to characterize are between 100 and 200 mesh (U.S. Standard sieve sizes), but sizes down to 50 mesh (e.g., -50/+70 mesh fraction), or up to 270 mesh (e.g., -200/+270 mesh fraction), have been shown to have differences in carbon black

concentration in "good" vs. "poor" dispersing samples. Particle sizes in the -40/+50 mesh range and larger do not provide adequate differentiation between "good" and "poor" samples, nor do they have much variation in carbon black content, probably due to the low surface to volume ratio, and thus relatively minor amount of carbon black versus polymer in these larger particles (for example, the coating or core-shell morphology).

The carbon black content data was compared to the dispersion test ratings for different EPDM samples analyzed, and the comparisons are shown in Figures 2-7. As discussed above, the critical carbon black content depends on the particle size as suggested by Figure 1. As seen from Figure 2-7, the EPDM samples with high dispersion ratings (poor dispersion) generally had relatively high carbon black contents in the small particle fraction. Each figure was divided into four quadrants by drawing a line at the "30 count" transition, which represents acceptable dispersion for automotive weather-strip applications by the traditional dispersion rating test, and a vertical line denoting a "critical carbon black concentration," below which acceptable dispersion ratings of 30 or lower were observed. With few exceptions, low dispersion rated ("good") samples were found to the left of the vertical line, and high dispersion rated ("poor") samples were found to the right of the vertical line. For each comparison, the critical concentration represented the concentration of carbon black in the particular size fraction, above which, poor dispersion was frequently observed. The critical concentration was found to be consistent for two products tested (46140 and 47085), as shown in Figure 8. Since these two products vary widely in Mooney viscosity (140 and 85, respectively), this figure shows that the critical carbon black content is independent of Mooney viscosity.

As shown in Figure 9, the relation between the critical carbon black concentration (wt %) and the average sieve size (in units of length - micron) for a given fraction can be described by a linear equation.

Figure 10 shows that, surprisingly, there was no correlation between dispersion rating and carbon black content, as determined by a furnace pyrolysis method, of the "whole polymer" sample; that is, the correlation is only observed in the small particle size fractions of the overall particle size distribution. EPDM samples

that have a carbon black content, in a given small size fraction, less than the corresponding critical concentration (determined by comparison of dispersion testing and small particle carbon black concentration, or by mathematical equation based on a comparison of dispersion testing and small particle carbon black concentration), provide improved dispersible polymer, especially for aesthetically demanding applications, such as extruded profiles for automotive and other end uses. The inventive compositions are especially useful when the Mooney Viscosity of the gas phase polymerized EPDM is high, since the incidence and severity (by dispersion count rating) of poor dispersion is greater in higher Mooney Viscosity polymers.

The inventive analyses, based on the mathematical relationships developed herein, can be used to determine the dispersibility of EPDM particles in soft formulations as described herein. The analyses do not require the labor intensive process of repeated dispersion tests. The inventive processes can be readily modified by those skilled in the art to correlate dispersibility with acceptable defect levels for other end use applications.