Abstract: A composition comprising a polyolefin, a polyorganosiloxane having at least two alkenyl groups per molecule, and calcium silicate where the polyorganosiloxane is cured after mixing using an organohydrido silicon compound and a hydrosilation catalyst to create a thermoplastic vulcanizate, provides excellent fire resistance. In particular such compositions when tested by burning at 40 to 88 kW/m2 external flux generate significantly less heat and smoke, and generate tougher chars compared to polyolefins alone, or mixtures of thermoplastic polyolefin resin, polyorganosiloxane and calcium silicate where the composition is not cured after mixing.

Abstract: A composition comprising a polyolefin, a polyorganosiloxane having at least two alkenyl groups per molecule, and calcium silicate where the polyorganosiloxane is cured after mixing using an organohydrido silicon compound and a hydrosilation catalyst to create a thermoplastic vulcanizate, provides excellent fire resistance. In particular such compositions when tested by burning at 40 to 88 kW/m2 external flux generate significantly less heat and smoke, and generate tougher chars compared to polyolefins alone, or mixtures of thermoplastic polyolefin resin, polyorganosiloxane and calcium silicate where the composition is not cured after mixing.

Abstract: Curable liquid silicone rubber compositions that are curable to form silicone elastomers which are useable as fire resistant sealants. These compositions have low heat release and form hard chars on burning, and comprise: (A) a liquid polyorganosiloxane polymer described by the formula  where each R1 is independently selected from the group consisting of alkyl, alkenyl, aryl, and halogenated alkyl groups having from 1 to 18 carbon atoms, each R2 is independently selected from the group consisting of hydroxyl, alkoxy, alkenyl, and alkynyl groups, and x is an integer having a value of from about 10 to 1500, (B) a cross-linking organosilicon compound having at least 3 silicon-bonded reactive groups, (C) a catalyst capable of promoting the reaction between the silicon-bonded R2 groups of Component A and the silicon-bonded reactive group of Component B, (D) wollastonite, and (E) an optional reinforcing filler.

Abstract: A method for the preparation of hydrophilic silica gels with high pore volume. In the preferred method a hydrophilic silica hydrogel treated with an organosilicon compound to effect hydrophobing of the silica hydrogel is heated in the presence of an oxidizing atmosphere to a temperature sufficient to reduce the hydrophobicity imparted by the surface treatment thereby producing a hydrophilic silica gel having high pore volume.

Abstract: A curable silicone wire and cable coating composition with improved flame resistance at heat flux rates of 50 to 90 kW/m2, made by mixing ingredients comprises: (A) 30 to 90 weight percent of a heat-curable non-halogenated organosiloxane polymer, containing at least 2 alkenyl groups per molecule, (B) 1 to 65 weight percent of a reinforcing silica filler, based on the total composition, (C) 5 to 70 weight percent wollastonite having an average particle size of 2 to 30 &mgr;m, based on the total composition, and (D) curing component sufficient to cure the composition.

Abstract: A cured silicone foam exhibiting high flame resistance and forming hard chars on burning, contains from about 1 to 60 percent by weight of wollastonite mineral, based on the weight of the composition. The silicone foam can be formed from any of the curable polyorganosiloxane foam-forming compositions known in the art. Preferred are those polyorganosiloxane foams cured using a platinum group metal catalyst. In a preferred composition the silicone foam is formed by curing a composition comprising a liquid polyorganosiloxane containing an average of at least two alkenyl radicals per molecule, an organohydrogensiloxane containing at least three silicon-bonded hydrogen atoms per molecule, a hydroxyl-containing compound, wollastonite, and a platinum catalyst.