| abstract |
A silicone foam which hardens at room temp. is prepd. by pressing a mixt. of a 1-component silicone compsn. and a low-boiling solvent, through a valve, from a bag by means of surface pressure on the bag. The silicone is esp. cross-linked by atmos. moisture. A mixt. contg. 60-90 wt.% of silicone compsn. and 40-10% of solvent may be used. The silicone compsn. pref. contains a filler, and may have the compsn.: (a) 15-85 wt.% OH-terminated silicone polymer, (b) 0-35% silicone oil, (c) 1-25% silicone crosslinking agent reactive with atmos. moisture, (d) 0-2% catalyst. w.r.t. the crosslinking agent, and (e) 5-70% filler. The silicone polymer is esp. of the methyl or phenyl type. The solvents are esp. (halo) hydrocarbons, e.g. CCl3F, F2ClC.CC1F2 or petroleum ether. After-foaming and loss of material are avoided. The vol. of foam is reproducible. |