| abstract |
Release compositions include(a) from zero to about 30 parts by weight of a polymer selected from the group consisting ofwherein R1, R2, R3, R6, R7, R10, R11, and R12 are each independently selected from an alkyl group, an alkenyl group, an aryl group, and an aralkyl group, such that at least one of R6 and R7 is an alkenyl group,l, m, and n are each independently an integer so long as the polymer contains greater than 3 mol % vinyl-containing siloxane groups; a (vinyl siloxy)(siloxy)-modified silica having a vinyl content of at least about 0.4 vinyl equivalent/kg; and a combination thereof;(b) more than about 20 parts by weight of a polymer having the formulawherein R13, R14, R15, R18, R19, R22, R23, and R24 are each independently selected from an alkyl group, an alkenyl group, an aryl group, and an aralkyl group, such that at least two of R13, R14, R15, R18, R19, R22, R23, and R24 are alkenyl groups,p, q, and r are each independently integers so long as the polymer has less than 3 mol % vinyl-containing siloxane groups; and(c) up to about 20 parts by weight of a cross-linking agent of the formulawherein R36, R37, R38, R43, R44, and R45 are each independently selected from hydrogen, an alkyl group, an aryl group, and an aralkyl group,X is O, or a divalent organic linking group, ands and t are independently integers so long as there are at least two functional groups capable of cross-linking per molecule. |