| 摘要 |
PROBLEM TO BE SOLVED: To obtain a solid mold release agent which is not sticky at room temp. and exhibits good mold release characteristics in long use at high-temps. by using a copolymer formed from an organopolysiloxane and a (meth)acrylic polymer as the main ingredient. SOLUTION: This mold release agent is prepd. by using, as the main ingredient, a copolymer which has a softening point of 60-130 deg.C and an organopolysiloxane content of 20-70wt.% and is either a copolymer of an alkylmercaptan (e.g. decylmercaptan or dodecylmercaptan), a free-radical- polymerizable unsatd. dimethylpolysiloxane, and another free-radical- polymerizable monomer or a block or graft copolymer formed by the free- radical copolymn. of an organopolysiloxane with a (meth)acrylic copolymer in the presence of a chain transfer agent comprising a mercapto compd. represented by formula I (wherein R<1> is a 1-12C divalent hydrocarbon group; k is 0-10; n is 1-200; and Me is CH3 ) or formula II (wherein R<1> and n are each the same as in formula I; and L is 1-10). |
