Patent ID: 6833407
Filing Date: 2004-12-21
Classification: C09D,Y10S

Abstract:
A one-part organopolysiloxane rubber composition for use as a high gloss coating on surfaces the composition consisting essentially of the product which is obtained by mixing the following:a) from about 20 to about 60 weight percent of one or more polydiorganosiloxane fluids of the formula HO[(R)2SiO]a(R)2SiOH â€ƒin which R is a monovalent alkyl or alkenyl radical having 1 to 8 carbon atoms or a phenyl radical, and n has an average value such that the viscosity is from about 100 to about 20,000 centipoise at 25Â° C.; b) from 0 to about 8 weight percent of a bifunctional chain extender of the general formula R24â€”Siâ€”X2 â€ƒwhere X is alkoxy or ketoximino and R4 is a monovalent alkyl or alkenyl radical having 1 to 8 carbon atoms or a phenyl radical; c) from 0 to about 50 weight percent of an inorganic extending or non-reinforcing filler; d) from about 0.5 to about 20 weight percent of an amorphous SiO2 reinforcing filler having a surface area of between about 50 to 250 m2/g and a particle size range between about 0.01 and 0.03 microns; e) from about 3 to about 15 weight percent of one or more crosslinking agents of general formula (X)4-mâ€”Siâ€”Râ€²m â€ƒwhere Râ€² is an alkyl, alkenyl or phenyl radical, X is an alkyl radical with a functional group selected from carboxyl, ketoximino, alkoxy, carbonyl or amine linked directly to the silicone atom, and m is an integer of from 0 to 2; f) from about 0.2 to about 3 weight percent of an adhesion promoter of the formula â€ƒin which R2 and R3 are independently selected from a monovalent alkyl or alkenyl radicals having 1 to 8 carbon atoms or a phenyl radical which may optionally be substituted with an alkyl radical having 1 to 8 carbon atoms, b is an integer between 0 and 3, and R1 is a saturated, unsaturated or aromatic hydrocarbon radical having 1 to 10 carbon atoms which may optionally contain a functional group; and g) from about 0.02 to about 3 weight percent of an organotin salt as a condensation catalyst.