HAIT SUKHENDU BIKASH (US)
SCHWAB JOSEPH J (US)
CARR MICHAEL J (US)
WO2001046295A1 | 2001-06-28 |
US6100417A | 2000-08-08 | |||
US5942638A | 1999-08-24 |
1. | A method for manufacture of an olef inbearing chemical comprising the steps of (a) mixing a silane coupling agent bearing an olefin with a chemical selected from the group consisting of polyhedral oligomeric silsesquioxanes and polyhedral oligomeric silicates, in the presence of an acidic or basic catalyst, and water, and (b) collecting the olefinbearing chemical through filtration. |
2. | The method of claim 1, wherein a plurality of silane coupling agents is used to incorporate different functional groups into the chemical. |
3. | The method of claim 1, wherein the process is utilized in a continuous or batch manufacturing method. |
4. | The method of claim 1, wherein the reaction medium is not heated from an external source above 40°C. |
5. | The method of claim 1, wherein the olefinbearing chemical is in a physical state selected from the group consisting of oils, amorphous, semicrystalline, crystalline, elastomeric, rubber, and crosslinked materials. |
6. | The method of claim 2, wherein the olefinbearing chemical includes nonreactive R groups. |
7. | The method of claim 1, further comprising the step of amination of the olefinbearing chemical. |
8. | The method of claim 7, wherein the amination changes a physical property of the chemical selected from the group consisting of adhesion to a polymeric surface, adhesion to a composite surface, adhesion to a metal surface, water repellency, density, low dielectric constant, thermal conductivity, glass transition, viscosity, melt transition, storage modulus, relaxation, stress transfer, abrasion resistance, fire resistance, biological compatibility, gas permeability, and porosity. |
9. | The method of claim 1, further comprising the step of isocyanation of the olefin bearing chemical. |
10. | The method of claim 9, wherein the isocyanation changes a physical property of the chemical selected from the group consisting of adhesion to a polymeric surface, adhesion to a composite surface, adhesion to a metal surface, water repellency, density, low dielectric constant, thermal conductivity, glass transition, viscosity, melt transition, storage modulus, relaxation, stress transfer, abrasion resistance, fire resistance, biological compatibility, gas permeability, and porosity. |
11. | The method of claim 1, further comprising the step of oxidation of the olefinbearing chemical. |
12. | The method of claim 11, wherein the oxidation changes a physical property of the chemical selected from the group consisting of adhesion to a polymeric surface, adhesion to a composite surface, adhesion to a metal surface, water repellency, density, low dielectric constant, thermal conductivity, glass transition, viscosity, melt transition, storage modulus, relaxation, stress transfer, abrasion resistance, fire resistance, biological compatibility, gas permeability, and porosity. |
13. | The method of claim 1, further comprising the step of incorporating the olefinbearing chemical into a product selected from the group consisting of fabrics, dyes, hair colorants, polishes, creams, lotions, lipsticks, mascara, foundations, soaps, absorbants, and makeup. |
14. | 4 The method of claim 13, wherein the incorporation of the olef inbearing chemical modifies a physical property selected from the group consisting of adhesion to a surface, water repellency, density, lubricity, luminescence, viscosity, modulus, filler reinforcement, plasticizer, relaxation, stress transfer, abrasion resistance, radiation resistance, biological compatibility, gas permeability, porosity, moisture and gas barrier, glass formation, static dissipation, biocide, nutrient release, exfoliant, dispersion aid, and strength. |
15. | The method of claim 6, further comprising the step of incorporating the olef inbearing chemical into a product selected from of the group consisting of fabrics, dyes, hair colorants, polishes, creams, lotions, lipsticks, mascara, foundations, soaps, absorbants, and makeup. |
16. | The method of claim 15, wherein the incorporation of the olef inbearing chemical modifies a physical property selected from the group consisting of adhesion to a surface, water repellency, density, lubricity, luminescence, viscosity, modulus, filler reinforcement, plasticizer, relaxation, stress transfer, abrasion resistance, radiation resistance, biological compatibility, gas permeability, porosity, moisture and gas barrier, glass formation, static dissipation, biocide, nutrient release, exfoliant, dispersion aid, and strength. |
17. | The method of claim 1, wherein the olef inbearing chemical includes an epoxy modified vinyl component. |
RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application Serial No.
60/684,666 filed May 25, 2005.
Field of the Invention
This invention relates generally to the methods and compositions of olefin containing
polyhedral oligomeric silsesquioxanes (POSS). More specifically, it relates to methods for
the continuous bulk production of polyvinyl POSS and derivative chemical products.
BACKGROUND OF THE INVENTION
Recent developments in nanoscience have enabled cost effective manufacture of
commercial quantities of polyhedral oligomeric silsesquioxanes that are best described as
nanostructured chemicals due to their precise chemical formula, hybrid (inorganic-organic)
chemical composition, large physical size relative to the size of traditional chemical
molecules (0.3-0.5 nm), and small physical size relative to larger-sized traditional fillers (>50
nm).
The commodity nature of organosilane coupling agents makes them highly desirable
for use as starting materials for nanoscopic POSS molecules. Prior art has taught the use of
silane coupling agents in the formation of POSS cages (U.S. Patent No. 6,972,312) and in the
functionalization of POSS cages with reactive groups (U.S. Patent No. 6,927,270).
This invention teaches continuous production methods for olefin bearing POSS and in
particular vinyl POSS cages. This advancement was needed as vinyl silanes are the lowest
cost reactive silane coupling agent and because vinyl POSS cages are highly desirable for
chemical derivatization into other chemical groups. Applications for olefin POSS and its
derivatives include improved composite resins, paints, coatings, adhesives, and surface
properties, which lead to fire resistance, printability, biocompatibility, and permeability
controlled, high Tg and heat distortion materials, glassification agents, printing aids, and
nanofiltration materials.
SUMMARY OF THE INVENTION
The present invention describes methods of continuous synthesis of polyolefin
containing polyhedral oligomeric silsesquioxanes. It also describes compositions of
chemicals derived from them.
The preferred compositions herein contain olefin functionalities on nanostructured chemicals and nanostructured oligomers (Figure 1). The nanostructured chemical classes
include polyhedral oligomeric silsesquioxanes, polysilsesquioxanes, polyhedral oligomeric
silicates, polysilicates, polyoxometallates, carboranes, boranes, and polymorphs of carbon.
Chemical derivatives from olefin containing POSS have been prepared by hydrosilation,
phosphorylation and thiolation (U.S. Patent No. 5,939,576), epoxidation and oxidation
methods (U.S. Patent Nos. 5,942,638 and 6,100,417), crossmetathesis, Heck additions, Diels-
Alder reactions, hydroformylation and Wacker oxidation. This invention describes
polyisocyanate derivatives, dhydroamination and subsequent carboxylation. Polyalcohol
derivatives are also described through ethylene and propylene oxide additions to olefinic
POSS.
Polyfunctional POSS systems are of utility in the formation of cross-links in materials
such as polycarbonate, polyesters, urethanes, epoxides, polyethers, polyamides, polyolefines,
bismaleimides, chitin, cellulose, polyacids, and silicones.
Vinyl containing nanostructured chemicals are particularly effective in polymers as
they control the motions of polymer chains, and segments, at the molecular level. Vinyl
containing nanostructured chemicals as also highly desirable in cosmetics, adhesives, paints,
coatings and dyes as the impart unique surface and physical properties. The incorporation of a
nanostructured chemical into a polymer favorably impacts a multitude of polymer physical
properties. Properties most favorably improved are heat distortion and flammability
characteristics. Other properties improved include time dependent mechanical and thermal
properties such as creep, compression set, shrinkage, modulus, and hardness. In addition to
mechanical properties, other physical properties are favorably improved, including lower
thermal conductivity, gas oxygen barrier and permeability, surface gloss and color. In
addition, vinyl containing nanostructured chemicals are highly useful for surface glassification and for chemical derivitization. These improved properties may be useful in a
number of applications, including composite materials and durable coatings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows examples of polyvinyl containing POSS nanostructured chemicals;
FIG. 2 illustrates the effect of water on yield of octavinyl POSS;
FIG. 3 illustrates the effect of acid on yield of octavinyl POSS;
FIG. 4 shows 29 Si NMR spectra of batch vs continuously produced octavinyl POSS;
FIG. 5 illustrates the process of vinyl hydroamination;
FIG. 6 illustrates the process of isocyanate formation; and
FIG. 7 illustrates the process of alcohol formation.
DEFINITION OF FORMULA REPRESENTATIONS FOR NANOSTRUCTURES
For the purposes of understanding this invention's chemical compositions the
following definition for formula representations of Polyhedral Oligomeric Silsesquioxane
(POSS) and Polyhedral Oligomeric Silicate (POS) nanostructures is made.
Polysilsesquioxanes are materials represented by the formula [RSiOi^] x where x
represents molar degree of polymerization and R = represents organic substituent (H, siloxy,
cyclic or aliphatic or olefininc, or aromatic groups that may additionally contain reactive
functionalities such as alcohols, isocyanates, esters, amines, ketones, olefins, ethers or halides
or which may contain fluorinated groups). Polysilsesquioxanes may be either homoleptic or heteroleptic. Homoleptic systems contain only one type of R group while heteroleptic
systems contain more than one type of R group.
POSS and POS nanostructure compositions are represented by the formula:
[(RSiOj .5) n ]∑# for homoleptic compositions
[(RSiOj _5) n (R'Si0i 5) m ]∑# for heteroleptic compositions (where R ≠ R')
[(RSiOj 5) n (RXSi0j o)m]∑# for functionalized heteroleptic compositions (where R groups
can be equivalent or inequivalent)
In all of the above R is the same as defined above and X includes but is not limited to
OH, Cl, Br, I, alkoxide (OR), acetate (OOCR), peroxide (OOR), amine (NR2) isocyanate
(NCO), and R. The symbols m and n refer to the stoichiometry of the composition. The
symbol ∑ indicates that the composition forms a nanostructure and the symbol # refers to the
number of silicon atoms contained within the nanostructure. The value for # is usually the
sum of m+n, where n ranges typically from 1 to 24 and m ranges typically from 1 to 12. It
should be noted that ∑# is not to be confused as a multiplier for determining stoichiometry, as
it merely describes the overall nanostructural characteristics of the system (aka cage size).
DETAILED DESCRIPTION OF THE INVENTION
The present invention teaches a continuous process for the manufacture of olefinic
containing nanostructured chemicals and chemical derivatives from them that are useful as
building blocks for the reinforcement of polymer coils, domains, chains, and segments at the
molecular level in thermoset and thermoplastic resins, oil or aqueous emulsions, latexes, and
suspensions.
Nanostructured chemicals, such as the olefin POSS structures illustrated in Figure 1,
can exist as solids, waxes, and oils. A variety of olefiinc R groups such as cyclohexene,
norbornene, allyl, and styrenyl can be considered for inclusion on nanostructured chemicals.
However, the lowest cost systems that are also commercially available commercially are the
vinylsilanes. Vinyltrialkoxysilanes and vinyltrichorosilane are commercially available in
industrial quantities. Historically the synthesis process for vinyl POSS systems has been
plaqued by low yields, long reaction times, and irreproducible product yields. The chemical
equation for synthesis of vinyl POSS involving trichloro or alkoxy silanes can be generically
represented as follows:
ViSiCl 3 + H 2 O → vinylPOSS + HCl (1)
ViSi(OR) 3 + H 2 O + HCl → vinylPOSS + ROH (2)
ViSiCl 3 + MeOH → vinylPOSS + HCl (3)
The chemical reactions illustrated in Equations 1, 2, and 3 are shown in
nonstoichiometric form as the effects of water, HCl, ROH (alcohol), and concentration of
silane have dramatic influences on product yield and the purity of isolated product. A wide
variety of olefin POSS structures can be obtained as illustrated in Figure 1.
To illustrate this point, Figures 2 and 3 describe the complex relationship of water and
acid relative to yield of the vinyl POSS cage. Furthermore, the concentration of the acid in
equations 2 and 3 can be varied from 1% to 39% with a preferred concentration of 37.9%.
In the design of a continuous process it is also desirable to recognize the chemical
stability and the ability to isolate the olefin POSS products from the reaction medium. In
Equations 1-3, the vinyl POSS is both chemically stable to the reaction medium and
insoluble. The insolubility of the POSS product, in the reaction medium, facilitates its
collection via filtration of the reaction mixture. The collection of product is further facilitated by running the reaction at room temperature which avoids the loss of product due to reactions
or solubilzation that can occur at elevated temperatures.
The concentration of silane added to the reaction medium can be varied from 0.01 M -
5.0 M. A preferred concentration range is 0.3 M to 2.0 M, and a more preferred concentration
for continuous reaction purposes is 1.3 M - 1.5 M.
While a continuous process has been established for each reaction illustrated in
Equations 1-3, equations 1 and 3 are less desirable, as they require equipment investments to
handle corrosive HCl byproducts. Equation 2 is more easily managed though use of readily
available plastic or glass lined reaction vessels and filtration equipment.
It should be further noted that equations 1 and 3 produce three equivalents of HCl for
each equivalent of vinyltrichlorosilane while equation 2 produces three equivalents of alcohol
per equivalent of vinytrialkoxy silane. The liberation of alcohol in equation 2 is highly
desirable as it aids in solubilization of the starting materials and in the solubilization of vinyl
POSS intermediates and resinous by-products. In the case of equations 1 and 3, alcohol is
required to rinse the final POSS products to remove such intermediates, oligomers and
polymers.
Finally, the formation of vinyl POSS in equations 1-3 is driven by the precipitation of
the product from the acid methanol solution. A resinous by-product is also produced in the
reaction but it does not precipitate from the reaction as it remains soluble in methanol.
EXAMPLES
General Process Variables Applicable To All Processes
As is typical with chemical processes, there are a number of variables that can be used
to control the purity, selectivity, rate and mechanism of any process. Variables influencing
the process for the formation of nanostructured chemicals (ej^ POSS/POS, etc.) include the
size, polydispersity, and composition of the nanostructured chemical desired, the kinetics,
thermodynamics, and aids used during the reaction process such as catalysts, cocatalyst,
supports, and surfactants, and other factors such as temperature, pressure, templates, solvent,
gases and mixtures thereof.
Vinyl POSS can be produced from vinyltrimethoxy, vinyltriethoxy silane or
vinyltrichloro silane (or related derivatives), either via the filtration of product every 24 hours
or by filtration of the product after the addition of silane over a period of successive 24 hour
additions, hi general it is preferred to filter and collect the reaction product once every 24
hours.
Example 1 - Vinyltrichorosilane Method
In the case of synthesis from vinyltrichloro silane, the vinyltrichloro silane is
premixed for 10 minutes with 3.5 equivalents of methanol. The prereacted solution (0.85%)
is then added to a stirred solution of methanol (65.7% v/v), HCl (32.7% v/v), and water
(0.65% v/v). The periodic addition of a solubilizing amount of methanol is required to
minimize the formation of a sticky white resinous by-product that can contaminate the
octavinyl POSS. The amount of MeOH required is variable and is determined by visual
solubilization of any sticky precipitated resin on the walls of the reaction vessel.
Example Ia
In a 1000 mL round bottom flask containing methanol (500 mL), HCl (250 ml), and water (5 mL) the mixture was allowed to come to room temperature. Vinyl trimethoxy silane
(6.5 mL) was added slowly to the reaction mixture and reaction was continued for 24 hours
with stirring (magnetic stirrer). In one case it was filtered and the reactor charged with
additional silane (6.5 mL), and the process is repeated 5 to 20 times. 20 time addition and
filtration produced 35.3% Vi8T8. (Yield was based on the final product, which was washed
with methanol and dried.) 10 times addition and no filtration produces 32.8% Vi8T8. (Yield
was based on the final product, which was washed with methanol and acetone and dried in
vacuum).
Example Ib
hi a 1000 mL round bottom flask containing methanol (500 mL), HCl (250 ml), and
water (5 mL) added slowly, the mixture was allowed to come to room temperature. Vinyl
trimethoxy silane (6.5 mL) was added slowly to the reaction mixture and reaction was
continued for 24 hours with stirring (magnetic stirrer). Total yield of 5 times
addition/filtration was 40.8%. Total yield of 5 times addition/no filtration was 40.8%. (Yield
was based on the final product which was washed with methanol and dried)
Example 2 - Vinyltrialkoxysilane Method
The process for producing octavinyl POSS from vinyltrimethoxy silane involves the
room temperature addition of the silane (0.85% v/v) every 24 hours to a stirred solution of
methanol (65.7% v/v), HCl (32.7% v/v), water (0.65% v/v). The reaction mixture is capable
of continuously producing octavinyl POSS either via the successive filtration of product or by
the continuous addition of silane.
Alternately, in a 1000 mL round bottom flask containing methanol (500 mL), HCl
(250 ml), and water (5 mL) added slowly, the mixture was allowed to come to room
temperature. Vinyl trimethoxy silane (6.5 mL) was added slowly to the reaction mixture and
reaction was continued for 24 h with stirring (magnetic stirrer). In one case it was filtered and
the reactor charged with additional silane (6.5 mL), and the process repeated 5 to 20 times.
In another case the reactor was charged with additional silane (6.5 mL) and the process was
repeated 5 to 20 times.
Example 3 - Hydroamination of Vinyl POSS
The hydroamination of olefins is a well known reaction. Figure 5 illustrates
hydroamination of vinyl POSS. A 50 g sample of vinyl POSS is suspended in a liquid
ammonia solution and to this PtBr 2 and nBuψPBr is added. The mixture was allowed to react
over 8 hours to product the desired octaminoethyl POSS. The product was isolated as a white
solid.
Example 4 - Polyisocvanate Formation
A 50g sample of octaminoethyl POSS was reacted with phosgene for 4 hours at 50°C to
produce the octaethylisocyante POSS. The product was isolated as a white solid. Figure 6
illustrates polyisocyanate formation with POSS.
Example 5 - Hvdrolvtic Oxidation of Vinyl POSS
Transition metal oxides such as OsO 4 and MnO 4 " have long been known to be
powerful oxidizing agents. Amine catalyzed osmylation followed by hydrolysis is a known
method to produce dialcohol products from vinyl groups. A 50 g sample of vinyl POSS was
stirred into osmium tetroxide. The mixture was allowed to react for 2 hours and then washed
with aqueous acid to produce a white solid of octaethylglycol POSS that was collected
through filtration. Figure 7 schematically shows the process of alcohol formation.
While certain representative embodiments and details have been shown for purposes of illustrating the invention, it will be apparent to those skilled in the art that various changes in the methods and apparatus disclosed herein may be made without departing from the scope of the invention which is defined in the appended claims.
What is claimed is: