| 摘要 |
The amount of solvent-extractable materials present in organosiloxane gels cured by a platinum-catalyzed hydrosilylation reaction can be reduced without sacrificing other desirable properties the gels when the curable composition used to prepare the gel comprise a first polydiorganosiloxane with vinyl or other ethylenically unsaturated hydrocarbon radicals only at the terminal positions, a second polydiorganosiloxane with silicon bonded hydrogen atoms only at the terminal positions and a crosslinking reactant containing at least three alkenyl radicals or silicon-bonded hydrogen atoms per molecule. The number of silicon-bonded hydrogen atoms or alkenyl radicals in excess of 2 per molecule of crosslinking reactant constitute from 10 to 30 percent of these reactive groups present in the curable composition.
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