Solvent resistant, room temperature vulcanizable silicone rubber compositions are improved by blending a siloxane resin of the type having silsesquioxane units containing a perfluorinated alkyl ethyl radical thereon with a vinyl-containing polymer and a hydride-containing resin or a hydrogen-containing polysiloxane as a cross-linking agent. The solvent resistant room temperature vulcanizable silicone rubber compositions also contain a catalyst, such as, a platinum catalyst. The compositions optionally contain filler. An example of the siloxane resin having silsesquioxane units and perfluorinated alkyl radical thereon is R"SiO. sub.1.5 wherein R" is a (--CH.sub.2 --).sub.a R' radical where R' is perfluoroalkyl of 1 to about 8 carbon atoms, a is at least 2 but less than 10, and (--CH.sub.2 --).sub.a is a straight or branched chain, and in a preferred embodiment, R' is --CF.sub.3, and a is 2, and the R"SiO. sub.1.5 is derived from 3,3,3-trifluoropropyltrichlorosilane.
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