Organohydrogenpolysiloxane resin and silicone composition
AssigneeDow Corning Corporation
InventorBizhong Zhu
Life of this patent
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Abstract
An organohydrogenpoly siloxane resin having the formula (I): (R1R32SiO½)w(R32SiO½)x(R1SiO3/2)y(SiO4/2)z, wherein R1 is C1 to C10 hydrocarbyl or C1 to C10 halogen-substituted hydrocarbyl, both free of aliphatic unsaturation, R3 is R1 or an organosilylalkyl group having at least one siliconbonded hydrogen atom, w is from 0 to 0.8, x is from 0 to 0.6, y is from 0 to 0.99, z is from 0 to 0.35, w+x+y+z=1, y+z/(w+x+y+z) is from 0.2 to 0.99, w+x/(w+x+y+z) is from 0.01 to 0.8, and at least 50 mol % of the groups R3 are organosilylalkyl; a silicone composition containing the resin, and a cured silicone resin prepared by curing the silicone composition.
Claims10
An organohydrogenpolysiloxane resin having the formula:
- (R1R32SiO1/2)w(R32SiO2/2)x(R1SiO3/2)y(SiO4/2)z,
- wherein R1 is C1 to C10 hydrocarbyl or C1 to C10 halogen-substituted hydrocarbyl, both free of aliphatic unsaturation, R3 is R1 or an organosilylalkyl group having at least one silicon-bonded hydrogen atom, w is from 0 to 0.8, x is from 0 to 0.6, y is from 0 to 0.99, z is from 0 to 0.35, w+x+y+z=1, y+z/(w+x+y+z) is from 0.2 to 0.99, w+x/(w+x+y+z) is from 0.01 to 0.8, and at least 50 mol % of the groups R3 are organosilylalkyl.
A silicone composition, comprising:
- (A) an organopolysiloxane resin having an average of at least two silicon-bonded alkenyl groups per molecule, wherein the resin has the formula:
- (R1R22SiO1/2)w(R22SiO2/2)x(R1SiO3/2)y(SiO4/2)z,
- wherein R1 is C1 to C10 hydrocarbyl or C1 to C10 halogen-substituted hydrocarbyl, both free of aliphatic unsaturation, R2 is R1 or alkenyl, w is from 0 to 0.8, x is from 0 to 0.6, y is from 0 to 0.99, z is from 0 to 0.35, w+x+y+z=1, y+z/(w+x+y+z) is from 0.2 to 0.99, w+x/(w+x+y+z) is from 0.01 to 0.8, and at least 50 mol % of the groups R2 are alkenyl;
- (B) an organosilicon compound having an average of at least two silicon-bonded hydrogen atoms per molecule in an amount sufficient to cure the composition, wherein the organosilicon compound comprises at least 0.5% (w/w) of an organohydrogenpolysiloxane resin having the formula (R1R32SiO1/2)w(R32SiO2/2)x(R1SiO3/2)y(SiO4/2)z, wherein R1 is C1 to C10 hydrocarbyl or C1 to C10 halogen-substituted hydrocarbyl, both free of aliphatic unsaturation, R3 is R1 or an organosilylalkyl group having at least one silicon-bonded hydrogen atom, w is from 0 to 0.8, x is from 0 to 0.6, y is from 0 to 0.99, z is from 0 to 0.35, w+x+y+z=1, y+z/(w+x+y+z) is from 0.2 to 0.99, w+x/(w+x+y+z) is from 0.01 to 0.8, and at least 50 mol % of the groups R3 are organosilylalkyl;
- and
- (C) a catalytic amount of a hydrosilylation catalyst.
Dependencies are inferred from the claim text.