The present invention is a method for making a fluorinated polydiorganosiloxane base composition and the composition prepared thereby. The base composition can be addition cured using a platinum-metal group catalyst and an organohydrogensiloxane crosslinker to form a fluorosilicone elastomer having improved resiliency and compression set properties.
Toporcer et al., U.S. Pat. No. 3,776,934, teach methylvinyldi(N-methylacetamido)silane and its manufacture. The amidosilane is taught useful as a chain extender in organosiloxane compositions.
Crossan et al., U.S. Pat. No 4,020,044, teach mixing a methylvinyldi(N-alkylacetamido) silane and hydroxyl endblocked polydiorganosiloxane and allowing the mixture to react at room temperature to provide a polydiorganosiloxane having increased molecular weight and methylvinylsiloxane units in the chain. Crossan et al. report the gums produced can be crosslinked through the use of organic peroxides.
Chaffee et al., U.S. Pat. No. 5,171,773, teach that a fluorinated polydiorganosiloxane elastomer having improved physical properties can be obtained through the use of a method which first reacts a hydroxyl endblocked methyl(fluoropropyl)siloxane having a Williams plasticity number greater than 5.7 mm with a methylvinyldi(N-alkylacetamido)silane to give a chain-extended polymer having pendant vinyl groups only at the location of the chain extension. Chaffee et al. teach the chain extend polymer can be mixed with a fumed silica having a surface area of about 400 m.sup.2 /g. The resulting composition can be peroxide cured to form a silicone elastomer.