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Title:
CATALYST COMPONENTS FOR THE POLYMERIZATION OF OLEFINS
Document Type and Number:
WIPO Patent Application WO/2016/050662
Kind Code:
A1
Abstract:
A catalyst component comprising Ti, Mg, CI, and an electron donor compound having porosity of at least 0.2 cm3/g and characterized by the fact that it further comprises Cu oxide, with the proviso that when the electron donor compound is selected from esters of phthalic acids, the porosity is of at least 0.45 cm3/g.

Inventors:
GUIDOTTI SIMONA (IT)
LIGUORI DARIO (IT)
MORINI GIAMPIERO (IT)
Application Number:
PCT/EP2015/072200
Publication Date:
April 07, 2016
Filing Date:
September 28, 2015
Export Citation:
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Assignee:
BASELL POLIOLEFINE SRL (IT)
International Classes:
C08F10/06; C08F4/657
Foreign References:
EP2712874A12014-04-02
EP0519342A21992-12-23
EP2787014A12014-10-08
Attorney, Agent or Firm:
GIBERTI, Stefano (Intellectual PropertyP.le Donegani 12, Ferrara, IT)
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Claims:
CLAIMS

What is claimed is:

1. A solid catalyst component for the (co)polymerization of olefins CH2=CHR, in which R is a hydrocarbyl radical with 1-12 carbon atoms, optionally in mixture with ethylene, comprising Ti, Mg, CI, and an electron donor compound having a porosity determined by mercury method and deriving from pore with radius equal to or less than 1 μιη of at least 0.2 cm /g and characterized by the fact that it further comprises Cu oxide, with the proviso that when the electron donor compound is selected from esters of phthalic acids, the porosity is of at least 0.45 cm /g.

2. The solid catalyst component of claim 1 in which the amount of Cu oxide ranges from 0.1 to 5% wt expressed as Cu atoms and based on the total weight of the solid catalyst component.

3. The solid catalyst component of claim 2 in which the amount of Cu oxide ranges from 0.1 to 3% by weight expressed as Cu atoms and based on the total weight of solid catalyst component.

4. The solid catalyst component of claim 1 in which the total amount of Ti ranges from 0.5 to 6% by weight.

5. The solid catalyst component of claim 1 in which the Cu oxide is CuO.

6. The solid catalyst component of claim 1 in which the porosity is higher than 0.25 cm /g with the proviso that when the electron donor compound is selected from esters of phthalic acids, the porosity is of at least 0.5 cm /g.

7. The solid catalyst component of claim 1 in which electron donor compound is selected from esters, ethers, amines, silanes and ketones or mixtures thereof.

8. The solid catalyst component of claim 7 in which electron donor compound is chosen from the group consisting of alkyl and aryl esters of optionally substituted aromatic mono or polycarboxylic acids, esters of malonic acids, esters of glutaric acids and esters of maleic acids and 1,3 diethers of the formula:

wherein R, R1, Rn, Rm, Rw and Rv equal or different to each other, are hydrogen or hydrocarbon radicals having from 1 to 18 carbon atoms, and RVI and Rvn, equal or different from each other, have the same meaning of R-Rv except that they cannot be hydrogen; one or more of the R-Rvn groups can be linked to form a cycle.

9. A catalyst for the polymerization of olefins CH2=CHR, in which R is a hydrocarbyl radical with 1-12 carbon atoms, optionally in mixture with ethylene, comprising the product obtained by contacting:

(i) the solid catalyst component according to anyone of claims 1-8;

(ii) an alkylaluminum compound and,

(iii) optionally an external electron donor compound.

10. The catalyst according to claim 9 in which the alkyl-Al compound (ii) is chosen among the trialkyl aluminum compounds.

11. The catalyst according to claim 9 in which the external donor compounds is selected from silicon compounds of formula (R6)a(R7)bSi(OR8)c, where a and b are integers from 0 to 2, c is an integer from 1 to 4 and the sum (a+b+c) is 4; R6, R7, and Rg, are alkyl, cycloalkyl or aryl radicals with 1-18 carbon atoms optionally containing heteroatoms.

12. A process for the (co)polymerization of olefins CH2=CHR, in which R is hydrogen or a hydrocarbyl radical with 1-12 carbon atoms, carried out in the presence of the catalyst according to anyone of claims 9-11.

13. A process according to claim 12 in which propylene and small amounts of ethylene and/or other olefins CH2=CHR are copolymerized to produce propylene copolymers containing up to 10% weight of ethylene and/or said CH2=CHR olefins different from propylene.

Description:
CATALYST COMPONENTS FOR THE POLYMERIZATION OF OLEFINS

FIELD OF THE INVENTION

[0001] The present disclosure relates to catalyst components for the (co)polymerization of olefins, in particular propylene, comprising Mg, Cu, Ti and halogen elements and at least an electron donor compound. The present disclosure further relates to the catalysts obtained from said components and to their use in processes for the (co)polymerization of olefins in particular propylene.

BACKGROUND OF THE INVENTION

[0002] Catalyst components for the stereospecific polymerization of olefins, such as propylene, are widely known in the art and they are of the Ziegler-Natta category type. The first catalyst of this type widely used in the industry was based on the use of solid T1CI 3 obtained by reduction of T1CI 4 with aluminum alkyls. The activity and stereo specificity of the catalysts were not so high so that the polymer had to be subject to a deashing treatment to remove the catalyst residues and to a washing step for removing the atactic polymer produced. Nowadays, the most spread out catalyst family used industrially comprises a solid catalyst component, constituted by a magnesium dihalide on which are supported a titanium compound and an internal electron donor compound, used in combination with an Al-alkyl compound. Conventionally these catalysts are used together with an external donor (for example an alkoxysilane) which helps in obtaining higher isotacticity. One of the preferred classes of internal donors is constituted by the esters of phthalic acid, diisobutylphthalate being the most used. The phthalates are used as internal donors in combination with alkylalkoxysilanes as external donor. This catalyst system is capable of giving good performances in terms of activity, and propylene polymers with high isotacticity and xylene insolubility. A particular type of these catalysts, those endowed with a relatively high porosity are also used in the preparation of high impact heterophasic copolymers comprising a crystalline propylene homo or copolymer matrix and a substantial amount, in certain applications more than 50 wt, of a very low crystalline, highly soluble in xylene ethylene based copolymer. [0003] For this last specific application the catalyst has to show also a good morphological stability allowing to produce a substantial amount of low cristallinity copolymer without showing phenomena of clogging, formation of chunks and particle agglomeration or adhesion to reactor walls.

[0001 ] The high porosity phthalate-based catalysts are generally endowed with this feature as shown by EP 395083 disclosing obtained by contacting a titanium compound, an electron donor compound (phthalate), with a MgCl 2 e (EtOH) m in which m is from 0.15 to 1.7 that has been in turn obtained by partial dealcoholation of adducts with a higher alcohol content.

[0002] As a drawback, the increase of the catalyst porosity may lead to a corresponding decrease of the catalyst performances in terms of polymerization activity and isospecificity. This latter would require additional amounts of external donors to be added which, in turn, would penalize the catalyst activity.

[0003] It would be therefore general interest the possibility of increasing the intrinsic capability of these solid catalyst components to produce stereoregular polymers. In fact, an intrinsically more stereospecific catalyst component would allow to use a lower amount of stereoregulating external donor to reach the target of polymer xylene insolubility and this, in turn, would be translated into the possibility of obtaining a higher plant productivity.

[0004] In US 4,613,655 substantial amounts (30% by weight or higher) of different inorganic compounds and, among them Cu 2 Cl 2 (table VII), is mixed with MgCl 2 and then ground in the presence of TiCl 4 in order to produce a catalyst. Apart from the effect of dilution of MgCl 2, the catalyst, used in the ethylene polymerization, did not show any improvement from the presence of Cu 2 Cl 2 . The catalysts have negligible porosity.

[0005] JP2010-155949 discloses the preparation of solid catalysts components according to several techniques all of them having in common the use of copper chlorides at various stages of preparation. According to this reference, the catalyst components containing Cu allows to increase the catalyst activity while the stereo specificity is maintained at the same level of the comparative catalyst (not containing Cu) or slightly increased. The catalyst have low and insufficient porosity. [0006] Now the applicant has surprisingly found that it is possible to increase the stereo specificity of porous catalyst components based on Mg containing support on which are supported titanium atoms and donors by modifying it with Cu oxide compounds.

SUMMARY OF THE INVENTION

[0007] It is therefore an object of the present disclosure a solid catalyst component comprising Ti, Mg, CI, and an electron donor compound having a porosity determined by mercury method deriving from pore with radius equal to or less than 1 μιη of at least 0.2 cm /g and characterized by the fact that it further comprises Cu oxide, with the proviso that when the electron donor compound is selected from esters of phthalic acids, the porosity is of at least 0.45 cm /g.

DETAILED DESCRIPTION OF THE INVENTION

[0008] Preferably, the amount of Cu oxide ranges from 0.1 to 5% wt expressed as

Cu atoms and based on the total weight of the solid catalyst component, more preferably it ranges from 0.1 to 3% and especially from 0.2 to 2%wt.

[0009] The Cu/Ti weight ratio ranges from 0.01 to 0.5, preferably from 0.02 to 0.40.

[0010] Preferably, more than 60% and more preferably more than 70% of the titanium atoms are in +4 valence state. The total amount of Ti is typically equal to, or higher than, 0.5% and preferably higher than 0.8%wt with respect to the total weight of the solid catalyst component. In a specific embodiment it ranges from 0.5 to 6% more preferably from 0.8 to 5%.

[0011] Preferably, CuO is used as Cu oxide.

[0012] The particles of solid component have substantially spherical morphology and average diameter comprised between 5 and 150 μιη, preferably from 20 to 100 μιη and more preferably from 30 to 90 μιη. As particles having substantially spherical morphology, those are meant wherein the ratio between the greater axis and the smaller axis is equal to or lower than 1.5 and preferably lower than 1.3.

[0013] The Mg atoms preferably derive from magnesium chloride and more preferably from magnesium dichloride. [0014] The titanium atoms belong to compounds of formula Ti(OR) n X4_ n in which n is comprised between 0 and 4; X is halogen and R is an hydrocarbon radical, preferably alkyl, radical having 1-10 carbon atoms or a COR group. Among them, particularly preferred are titanium compounds having at least one Ti-halogen bond such as titanium tetrahalides or halogenalcoholates. Preferred specific titanium compounds are TiCl 4 , and Ti(OEt)Cl 3 .

[0015] The components of the present disclosure also comprise an electron donor compound (internal donor), selected from esters, ethers, amines, silanes and ketones or mixtures thereof. Particularly preferred classes are alkyl and aryl esters of optionally substituted aromatic mono or polycarboxylic acids such as for example esters of benzoic and phthalic acids, and esters of aliphatic acids selected from malonic, glutaric and maleic acids. Specific examples of such esters are n-butylphthalate, di- isobutylphthalate, di-n-octylphthalate, ethyl-benzoate and p-ethoxy ethyl-benzoate. Also, the diesters disclosed in WO2010/078494 and US 7,388,061 can be used. Among this class, particularly preferred are the 2,4-pentanediol dibenzoate derivatives. Moreover, can be advantageously used also the 1,3 diethers of the formula:

[0016] wherein R, R 1 , R n , R m , R w and R v equal or different to each other, are hydrogen or hydrocarbon radicals having from 1 to 18 carbon atoms, and R VI and R vn , equal or different from each other, have the same meaning of R-R v except that they cannot be hydrogen; one or more of the R-R vn groups can be linked to form a cycle. The 1,3-diethers in which R VI and R vn are selected from C C 4 alkyl radicals are particularly preferred.

[0017] Preferably, the final amount of electron donor compound in the solid catalyst component ranges from 1 to 25% by weight preferably in the range from 3 to 20% by weight. [0018] In a specific embodiment, the internal electron donor is selected from alkyl and aryl esters of optionally substituted aromatic mono or polycarboxylic acids and its amount ranges from 5 to 15%wt, the amount of Ti atoms is from 1 to 3%wt and the amount of Cu is from 0.4 to 1.5% wt.

[0019] In another specific embodiment the internal electron donor is selected 1,3 diethers of the formula (I) and its amount ranges from 8 to 20%wt, the amount of Ti atoms is from 2.5 to 6%wt and the amount of Cu is from 0.2 to 1.2% wt.

[0020] The porosity is preferably higher than 0.25 more preferably higher than

0.30 cm /g. When the internal donor is selected from esters of phthalic acids the porosity is preferably higher than 0.5, more preferably higher than 0.55 and especially ranging from 0.6 to 1 cm /g.

[0021] The preparation of the solid catalyst component can be carried out according to several methods.

[0022] According to one of the preferred method the solid catalyst component can be prepared by reacting a titanium compound of formula Ti(OR)n-yXy, where n is the valence of titanium and y is a number between 1 and n, preferably TiCl 4 , with a magnesium chloride deriving from an adduct of formula MgCi 2 pROH, where p is a number between 0.1 and 2.2, and R is a hydrocarbon radical having 1-18 carbon atoms, said reaction being carried out in the presence of the electron donor that can be added simultaneously or in sequence. The adduct can be suitably prepared in spherical form by mixing alcohol and magnesium chloride in the presence of an inert hydrocarbon immiscible with the adduct, operating under stirring conditions at the melting temperature of the adduct (100-130°C). Then, the emulsion is quickly quenched, thereby causing the solidification of the adduct in form of spherical particles. Example of spherical adducts prepared according to this procedure are described in USP 4,399,054 and USP 4,469,648. The so obtained adduct is then subject to thermally controlled dealcoholation (80-130°C) so as to obtain an adduct in which the number of moles of alcohol is generally lower than 2, preferably between 0.1 and 1.5.

[0023] In the preferred method of producing the catalyst of the present disclosure, the reaction with the Ti compound can be carried out by suspending the adduct (dealcoholated or as such) in cold TiCl 4 generally at 0°C. Preferably the adduct is used in an amount such as to have a concentration ranging from 20 to 100 g/1, and preferably from 30 to 90 g/1. The temperature is then gradually raised up until reaching a temperature ranging from 90-130°C and kept at this temperature for 0.5-3 hours. According to a preferred embodiment, the donor is added in this first stage of reaction and preferably when the temperature of the mixture is in the range of 0°- 40°C. The molar ratio with which it is used depends on the desired final amount of donor in the catalyst but generally the Mg/donor molar ratio may range from 1 to 25 and preferably from 5 to 20. After completing the reaction time stirring is stopped, the slurry is let to settle and liquid phase removed. A second stage of treatment with TiCl 4 is performed, preferably carried out at a temperature ranging from 70 to 110°C. When 1,3-diethers of formula (I) are used, it has been found preferable to feed again an aliquot of 1,3-diether more preferably when the temperature of the mixture is still in the range 40-80°C. Also in this case the amount of donor is to be selected according to the desired final amount on the catalyst but generally the total Mg/diether molar ratio may range from 1 to 15 and preferably from 3 to 10.

4] After completing the reaction time, stirring is stopped, the slurry is let to settle and liquid phase removed. Preferably, the solid catalyst component obtained after this step is contacted an additional time with the titanium compound and preferably with TiCl 4 under the same conditions described for the previous step with the difference that no donor is used. The so obtained solid can then be washed with liquid hydrocarbon under mild conditions and then dried. Several ways are available to add the Cu oxide. It is preferable use it in the form of particles having average size less than 60 μιη, preferably less than 30 μιη and more preferably less than 10 μιη. Cu oxide in the above mentioned particle size is either available commercially or it can be obtained by applying conventional techniques such as milling. In a specific embodiment the CuO is added to the MgCl 2 -alcohol system as a dispersion in alcohol. According to the preferred option, the Cu oxide is incorporated directly into the MgCl 2 *pROH adduct during its preparation. In particular, the Cu oxide can be added at the initial stage of adduct preparation by mixing it together with MgCl 2 and the alcohol. Alternatively, it can be added to the molten adduct before the emulsification step. In this latter case it is recommended to use the Cu oxide in particles having average particle size of less than 10 μιη.

[0025] The preparation of catalyst components in spherical form are described for example in European Patent Applications EP-A-395083, EP-A-553805, EP-A-

553806, EPA601525 and WO98/44001.

[0026] The solid catalyst component has an average particle size ranging from 5 to 120 μιη and more preferably from 10 to 100 μιη.

[0027] As mentioned, in any of these preparation methods the desired electron donor compounds can be added as such or, in an alternative way, can be obtained in situ by using an appropriate precursor capable of being transformed in the desired electron donor compound by means, for example, of known chemical reactions such as etherification, alkylation, esterification, transesterification etc.

[0028] The solid catalyst components according to the present invention are converted into catalysts for the polymerization of olefins by reacting them with organoaluminum compounds according to known methods.

[0029] In particular, an object of the present invention is a catalyst for the polymerization of olefins CH 2 =CHR, in which R is a hydrocarbyl radical with 1-12 carbon atoms, optionally in mixture with ethylene, comprising the product obtained by contacting:

(i) the solid catalyst component as disclosed above and

(ii) an alkylaluminum compound and,

(iii) an external electron donor compound.

[0030] The alkyl-Al compound (ii) is preferably chosen among the trialkyl aluminum compounds such as for example triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum. It is also possible to use alkylaluminum halides, alkylaluminum hydrides or alkylaluminum sesquichlorides, such as AlEt 2 Cl and Al 2 Et 3 Cl 3 , possibly in mixture with the above cited trialkylaluminums.

[0031] Suitable external electron-donor compounds include silicon compounds, ethers, esters, amines, heterocyclic compounds and particularly 2,2,6,6- tetramethylpiperidine and ketones. [0032] Another class of preferred external donor compounds is that of silicon compounds of formula (R6) a (R 7 ) b Si(ORg) c , where a and b are integers from 0 to 2, c is an integer from 1 to 4 and the sum (a+b+c) is 4; R 6 , R 7 , and Rg, are alkyl, cycloalkyl or aryl radicals with 1-18 carbon atoms optionally containing heteroatoms. Particularly preferred are the silicon compounds in which a is 1, b is 1, c is 2, at least one of R 6 and R 7 is selected from branched alkyl, cycloalkyl or aryl groups with 3-10 carbon atoms optionally containing heteroatoms and Rg is a C -Cw alkyl group, in particular methyl. Examples of such preferred silicon compounds are methylcyclohexyldimethoxysilane (C donor), diphenyldimethoxysilane, methyl-t-butyldimethoxysilane, dicyclopentyldimethoxysilane (D donor), diisopropyldimethoxysilane , (2- ethylpiperidinyl)t-butyldimethoxysilane, (2-ethylpiperidinyl)thexyldimethoxysilane, (3,3,3-trifluoro-n-propyl)(2-ethylpiperidinyl)dimethoxysilan e, methyl(3,3,3-trifluoro-n- propyl)dimethoxysilane. Moreover, the silicon compounds in which a is 0, c is 3, R 7 is a branched alkyl or cycloalkyl group, optionally containing heteroatoms, and Rg is methyl are also preferred. Examples of such preferred silicon compounds are cyclohexyltrimethoxysilane, t-butyltrimethoxysilane and thexyltrimethoxysilane.

[0033] The electron donor compound (iii) is used in such an amount to give a molar ratio between the organoaluminum compound and said electron donor compound (iii) of from 0.1 to 500, preferably from 1 to 300 and more preferably from 3 to 100.

[0034] Therefore, it constitutes a further object of the present invention a process for the (co)polymerization of olefins CH 2 =CHR, in which R is hydrogen or a hydrocarbyl radical with 1-12 carbon atoms, carried out in the presence of a catalyst comprising the product of the reaction between:

(i) the solid catalyst component of the invention;

(ii) an alkylaluminum compound and,

(iii) optionally an electron-donor compound (external donor).

[0035] The polymerization process can be carried out according to known techniques for example slurry polymerization using as diluent an inert hydrocarbon solvent, or bulk polymerization using the liquid monomer (for example propylene) as a reaction medium. Moreover, it is possible to carry out the polymerization process in gas-phase operating in one or more fluidized or mechanically agitated bed reactors.

[0036] The polymerization is generally carried out at temperature of from 20 to

120°C, preferably of from 40 to 80°C. When the polymerization is carried out in gas- phase the operating pressure is generally between 0.5 and 5 MPa, preferably between 1 and 4 MPa. In the bulk polymerization the operating pressure is generally between 1 and 8 MPa, preferably between 1.5 and 5 MPa.

As already explained, the catalyst of the invention show, in propylene homopolymerization an increased activity/stereospecificity balance particularly due to increased stereo specificity compared with prior art catalysts not containing Cu atoms or containing a Cu compound different from Cu oxide. The following examples are given in order to better illustrate the invention without limiting it.

[0037] CHARACTERIZATION

[0038] Determination of Mg, Ti ( TOT ) and Cu

[0039] The determination of Mg, Ti (TOT) and Cu content in the solid catalyst component has been carried out via inductively coupled plasma emission spectroscopy on "LC.P Spectrometer ARL Accuris".

The sample was prepared by analytically weighting, in a "Fluxy" platinum crucible", 0.1÷0.3 grams of catalyst and 2 grams of lithium metaborate/tetraborate 1/1 mixture. After addition of some drops of KI solution, the crucible is inserted in a special apparatus "Claisse Fluxy" for the complete burning. The residue is collected with a 5% v/v HNO 3 solution and then analyzed via ICP at the following wavelengths: Magnesium, 279.08 nm; Titanium, 368.52 nm; Copper, 327.40 nm.

[0040] Determination of porosity.

[0041] Porosity and surface area with mercury: the measurement is carried out using a Pascal 140-240 series porosimeter by Carlo Erba.

[0042] The porosity is determined by intrusion of mercury under pressure. For this determination a calibrated dilatometer (capillary diameter 3 mm) CD3P (by Carlo Erba) is used, that is connected to a reservoir of mercury and to a high-vacuum pump. A weighed amount of sample is placed in the dilatometer. The apparatus is then placed under high vacuum and is maintained in these conditions for ca. 20 minutes. The dilatometer is then connected to the mercury reservoir and the mercury is allowed to slowly fill the dilatometer, until it reaches the level marked on the dilatometer at a height of 10 cm. The valve that connects the dilatometer to the vacuum pump is closed and then the mercury pressure is gradually increased with nitrogen up to 100 kPa. Subsequently, the calibrated dilatometer is transferred into an autoclave with oil for high pressure in order to reach pressure values up to 200 MPa. Under the effect of the pressure, the mercury enters into the pores of the particles and the mercury level decreases accordingly.

The porosity (cm3/g), the pore distribution curve and the average pore size are directly calculated from the integral pore distribution curve, which is a function of both the volume reduction of the mercury and the applied pressure values. All these data are provided and elaborated by the porosimeter associated computer which is equipped with dedicated software supplied by Carlo Erba. After calculation, the average pores radius is given as weighted average of the single average pores radius contribution for each interval of porosity.

[0043] Determination of internal donor content

The determination of the content of internal donor in the solid catalytic compound was done through gas chromatography. The solid component was dissolved in acetone, an internal standard was added, and a sample of the organic phase was analyzed in a gas chromatograph, to determine the amount of donor present at the starting catalyst compound.

[0044] Determination of X.I.

2.5 g of polymer and 250 ml of o-xylene were placed in a round-bottomed flask provided with a cooler and a reflux condenser and kept under nitrogen. The obtained mixture was heated to 135°C and was kept under stirring for about 60 minutes. The final solution was allowed to cool to 25°C under continuous stirring, and the insoluble polymer was then filtered. The filtrate was then evaporated in a nitrogen flow at 140°C to reach a constant weight. The content of said xylene- soluble fraction is expressed as a percentage of the original 2.5 grams and then, by difference, the X.I. %.

[0045] Average Particle Size and Particle Size Distribution. [0046] A Malvern Mastersizer 2000 instrument was used which consists of three units:

1) optical unit; Optical core unit suitable for measurements of solids of sizes ranging from 0,02 to 2000μ, equipped with two laser beam sources: red He/Ne laser, power 5mw, wave length 633 nm., blue (diode) laser, wave length 450nm.

2) sampling Unit; Hidro 2000S automatic Sampling Unit for volumes between 50 and 120 ml, operating with internal capacity, centrifuge pump, stirrer and ultrasound probe with 40W power output.

3) PC console; Portable LG Pentium series, using Malvern Professional software for Windows 2000 or NT. Method of data elaboration using Mie optics theory (Refractive Index for sample =1.596; Refractive Index for n-heptane =1.39).

Method description

For the measurements n-heptane (plus 2 g/1 antistatic Span 80) is used as dispersing agent.

Measuring cell is loaded with dispersing agent, while pump/agitator speed is set up to 2205 RPM. Background measurement is then taken. Then sample is loaded, by using a dedicated loading mean for solids or slurries Obscuration is then checked on monitor. Once constant steady obscuration is reached, the sample is subject to ultrasound waves by bringing the intensity of ultrasound probe to full scale (100% of the regulator) for 30 seconds; after that data are acquired for the PSD measurement. The average size is given as P50.

The particle size distribution (SPAN) is calculated with the formula wherein P90 is the value of the diameter such that 90% of the total volume of particles have a diameter lower than that value; P10 is the value of the diameter such that 10% of the total volume of particles have a diameter lower than that value and P50 is the value of the diameter such that 50% of the total volume of particles have a diameter lower than that value..

[0047] EXAMPLES

Procedure for the preparation of the spherical adduct

An initial amount of MgCi 2 *2.8C 2 H 5 0H adduct containing the Cu compound was prepared according to the method described in Example 2 of W098/44009, but operating on larger scale and adding the Cu compound of the type and in the amount as indicated in Tables 1 and 2. A Cu oxide powder having average particle size (P50) of 5.26 μιη was slurred and stirred in anhydrous ethanol to get a 40%wt/vol of an homogeneous dispersion which was added to the ethanol/MgCl 2 mixture to prepare the said adduct. The CuO average particle size in said dispersion was found to be 6.4 μιη. The so obtained adduct was then subject to thermal dealcoholation at increasing temperatures from 30 to 130°C operating in nitrogen current until the desired molar alcohol content reported in tables 1 and 2 is obtained.

Procedure for the preparation of the diether-based solid catalyst component

Into a 500 ml round bottom flask, equipped with mechanical stirrer, cooler and thermometer 250 ml of TiCl 4 were introduced at room temperature under nitrogen atmosphere. After cooling to 0°C, while stirring, 9,9-bis(methoxymethyl)fluorene and 10.0 g of the spherical adduct (prepared as described above) were sequentially added into the flask. The amount of charged internal donor was such to meet a Mg/donor molar ratio of 6. The temperature was raised to 100°C and maintained for 2 hours. Thereafter, stirring was stopped, the solid product was allowed to settle and the supernatant liquid was siphoned off at 100°C. After the supernatant was removed, additional fresh TiCl 4 was added to reach the initial liquid volume again. The mixture was then heated at temperature in the range of 110°C and kept at this temperature for 1 hour. Stirring was stopped again, the solid was allowed to settle and the supernatant liquid was siphoned off. The solid was washed with anhydrous hexane six times in temperature gradient down to 60°C and one time at room temperature. The obtained solid was then dried under vacuum and analyzed.

Procedure for the preparation of the phthalate-based solid catalyst component

Into a 500 ml round bottom flask, equipped with mechanical stirrer, cooler and thermometer 250 ml of TiCl 4 were introduced at room temperature under nitrogen atmosphere. After cooling to 0°C, while stirring, diisobutylphthalate and 10.0 g of the spherical adduct (prepared as described above) were sequentially added into the flask. The amount of charged internal donor was such to meet a Mg/donor molar ratio of 8. The temperature was raised to 100°C and maintained for 2 hours. Thereafter, stirring was stopped, the solid product was allowed to settle and the supernatant liquid was siphoned off at 100°C. After the supernatant was removed, additional fresh TiCl 4 was added to reach the initial liquid volume again. The mixture was then heated at temperature in the range of 120°C and kept at this temperature for 1 hour. Stirring was stopped again, the solid was allowed to settle and the supernatant liquid was siphoned off. The solid was washed with anhydrous hexane six times in temperature gradient down to 60°C and one time at room temperature. The obtained solid was then dried under vacuum and analyzed.

General procedure for the polymerization of propylene

A 4— liter steel autoclave equipped with a stirrer, pressure gauge, thermometer, catalyst feeding system, monomer feeding lines and thermostating jacket, was purged with nitrogen flow at 70°C for one hour. A suspension containing 75 ml of anhydrous hexane, 0.76 g of AlEt 3 (6.66 mmol), an external donor in amount of 0.33 ÷ 0.66 mmol and 0.006 ÷ 0.010 g of solid catalyst component, previously precontacted for 5 minutes, was charged. Dicyclopentyldimethoxysilane, D donor, was used as external donor; Al/D donor molar ratios used are specified in Tables 1 and 2. Some tests described in Tables 1 and 2 were also carried out without any external donor. The autoclave was closed and the desired amount of hydrogen was added (in particular, 2 NL in D donor tests and 1.25 NL in tests without external donor were used). Then, under stirring, 1.2 kg of liquid propylene was fed. The temperature was raised to 70°C in about 10 minutes and the polymerization was carried out at this temperature for 2 hours. At the end of the polymerization, the non-reacted propylene was removed; the polymer was recovered and dried at 70°C under vacuum for 3 hours. Then the polymer was weighed and characterized.

[0048] Examples 1 - 2 and Comparative Examples CI - C4

The diether-based solid catalyst components were prepared from spherical adducts MgCl 2 *pC 2 H 5 0H using the general method described above. Their composition and related propylene polymerization performance are indicated in Table 1.

[0049] Example 3 and Comparative Examples C5 - C6

The phthalate-based solid catalyst components were prepared from spherical adducts MgCi 2 -pC 2 H 5 0H using the general method described above. Their composition and related propylene polymerization performance are indicated in Table 2. Comparative Examples C7

The porosity of the solid catalyst component prepared as described in example 6 of EP 2787014 was reported in table 2.

[0050] Table 1: Diether-based solid catalyst components from spherical adducts

[0051] Diether = 9,9-bis(methoxymethyl)fluorene, TEAL/D = 20 m.r.

[0052] Table 2: Phthalate-based solid catalyst components from spherical adducts

[0053] DIBP = diisobutyl phthalate, TEAL/D = 10 m.r.