method for preparation of solvent free hardbare mixtures and formed products manufactured under the thus prepared mixtures.

摘要

Organosilicon resins having excellent thermal shock resistance in either the filled or unfilled state are obtained by curing mixtures of (A) a copolymer of (in mole percent) 35 to 42 monophenylsiloxane, 0 to 12 diphenylsiloxane, 35 to 50 dimethylsiloxane and 8 to 15 vinylmethylsiloxane with (B) a copolymer of (in mole percent) 8 to 15 diphenylsiloxane, 30 to 55 methylhydrogensiloxane, 28 to 45 dimethylsiloxane and 5 to 12 trimethylsiloxane in amount such that there is a stoichiometric amount of SiH and Si vinyl +/- 10 percent of either ingredient. The preferred fillers are mixtures of 1/32 to 1/8 inch glass fibers and 2 to 8 microns crystalline silica.