Heat curable silicone-polyimide block copolymers

Claim 2

Heat curable compositions comprising, (A) an effective amount of an organic peroxide selected from the class consisting of benzoyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-ditertiarybutylperoxyhexane, tertiary butylperbenzoate, bis(2,4-dichlorobenzoyl)peroxide, tertiary butyl peroxide and tertiarybutylperoxyisopropyl carbonate, and (B) a norbornane or norbornene block copolymer comprising chemically combined blocks of a member selected from (i) polydiorganosiloxane and (ii) a mixture of polydiorganosiloxane and polyimide where the organo radicals of the polydiorganosiloxane are selected from the class consisting of the same or different C.sub.(1-13) monovalent hydrocarbon radicals and substituted C.sub.(1-13) monovalent hydrocarbon radicals and where the norbornane or norbornene groups in the block copolymer are substituted with radicals selected from the class consisting of hydrogen and C.sub.(1-8) alkyl radials.

Claim 3

A cured elastomer made from the composition of claim 1.

Claim 4

A composition in accordance with claim 1 where the organic peroxide is benzoyl peroxide.

Claim 5

A composition in accordance with claim 1, where the block copolymer has polydiorganosiloxane blocks which consist essentially of dimethylsiloxy units and methylvinylsiloxane units.

Claim 6

A heat curable composition comprising (A) an effective amount of an organic peroxide, and (B) a polydiorganosiloxane-polyimide block copolymer comprising by weight from 1 to 99% of polyimide blocks of the formula, ##STR20## chemically combined with from 99 to 1% of polydiorganosiloxane blocks of the formula, ##STR21## where R is a divalent C.sub.(2-20) organic radical selected from the class consisting of (a) aromatic hydrocarbon radicals having from 6-20 carbon atoms or halogenated derivatives thereof, (b) alkylene radicals or cycloalkylene radicals having from 2-20 carbon atoms (c) C.sub.(2-13) organo terminated polydiorganosiloxane, and (d) divalent radicals of the formula, ##STR22## Q 1 is a member selected from the class consisting of ##STR23## x is a whole number from 1 to 5 inclusive, Q is a tetravalent radical selected from ##STR24## where D is a member selected from ##STR25## R 8 is a divalent radical selected from ##STR26## and divalent organic radicals of the general formula, ##STR27## X is a member selected from the class consisting of divalent radicals of the formula, ##STR28## y is an integer from 1 to 5, R 1 -R 6 are selected from hydrogen and C.sub.(1-8) alkyl radicals and R 7 is the same or different C.sub.(1-13) monovalent hydrocarbon radical and substituted C.sub.(1-13) monovalent hydrocarbon radical, Y is a divalent radical selected from --O-- and --C(R 1 ) 2 .

Claim 7

A heat curable composition comprising (A) an effective amount of an organic peroxide, and (B) a polydiorganosiloxane-polyimide block copolymer comprising by weight from 1 to 99% of polyimide blocks of the formula, ##STR20## chemically combined with from 99 to 1% of polydiorganosiloxane blocks of the formula, ##STR21## where R is a divalent C.sub.(2-20) organic radical selected from the class consisting of (a) aromatic hydrocarbon radicals having from 6-20 carbon atoms or halogenated derivatives thereof, (b) alkylene radicals or cycloalkylene radicals having from 2-20 carbon atoms (c) C.sub.(2-13) organo terminated polydiorganosiloxane, and (d) divalent radicals of the formula, ##STR22## Q 1 is a member selected from the class consisting of ##STR23## x is a whole number from 1 to 5 inclusive, Q is a tetravalent radical selected from ##STR24## where D is a member selected from ##STR25## R 8 is a divalent radical selected from ##STR26## and divalent organic radicals of the general formula, ##STR27## X is a member selected from the class consisting of divalent radicals of the formula, ##STR28## y is an integer from 1 to 5, R 1 -R 6 are selected from hydrogen and C.sub.(1-8) alkyl radicals and R 7 is the same or different C.sub.(1-13) monovalent hydrocarbon radical and substituted C.sub.(1-13) monovalent hydrocarbon radical, Y is a divalent radical selected from --O-- and --C(R 1 ) 2 .

Claim 8

A heat curable composition in accordance with claim 5, where the organic peroxide is benzoyl peroxide.

Claim 9

A heat curable composition in accordance with claim 5, where the diorganosiloxane blocks of the polydiorganosiloxane-polyimide block copolymer consists essentially of chemically combined dimethylsiloxy units and methylvinylsiloxy units where there is 0.05 to 2 moles of methylvinylsiloxy units based on the total moles of diorganosiloxy units.