摘要 |
A platinum curing organosiloxane composition having improved hysteresis characteristics when cured. The composition requires the presence of a diorganovinylsiloxy terminated polydiorganosiloxane having a viscosity within a range of about 20 Paxs to 200 Paxs at 25 DEG C. and containing essentially no ethylenically unsaturated hydrocarbon radicals bonded to non-terminal silicon atoms and a diorganovinylsiloxy terminated polydiorganosiloxane having a viscosity within a range of about 0.1 Paxs to 200 Paxs at 25 DEG C., where from 1 to 5 percent of the non-terminal repeating units of the siloxane comprise a vinyl radical. In addition, the present composition comprises 10 to 30 weight percent of a reinforcing silica filler that has been treated with hexamethyldisilazane and 1,1,3,3-tetramethyl-1,3-divinyldisilazane, and an organohydrogensiloxane resin crosslinker comprising greater than 5 silicon-bonded hydrogen atoms per molecule.
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