| 摘要 |
PURPOSE:To obtain the title composition which can give a cured product excellent in hardness and rubber elasticity in excellent workability, by mixing an organopolysiloxane having a plurality of terminal vinyl groups with an organopolysiloxane, an organohydrogenpolysiloxane and a platinum (compound). CONSTITUTION:100pts.wt. organopolysiloxane (A) having a plurality of terminal vinyl groups of formula I (wherein R is an aliphatic unsaturated group-free (substituted) monovalent hydrocarbon group, a is 0 or 1 and n is a positive integer] is mixed with 5-150pts.wt. organopolysiloxane (B) containing units (a) of formula II (wherein b is 0-2), units (b) of formula III and units (c) of formula IV in such an amount that the molar ratio of the sum of a+b to component C is 0.5-2 and that the vinyl group content is 0.5-9wt.%, an organohydrogenpolysiloxane (C) having at least two Si-bonded hydrogen atoms in the molecule, in an amount to give 0.7-5 Si-bonded hydrogen atoms per vinyl group in components A and B and a platinum (compound) (D) in an amount of 0.1-300ppm.wt. (in terms of Pt) based on the total of components A-C. |
