Abstract: A process and a catalytic composition for carrying out a platinum catalyzed hydrosilylation reaction between an SiH-containing material and a terminal olefin. The process of the invention involves heating the reactants in the presence of a platinum catalyst and a promoter which is a hindered amine or phosphine, or acid salt thereof, the promoter containing at least 6 carbon atoms and having the formula ##STR1## Q is N or P; when Q is N, R is H, alkyl of 1-18 carbon atoms, nonterminal alkenyl of 4-18 carbon atoms, arylalkyl of 7-25 carbon atoms, or a derivative thereof; when Q is P, R is alkyl of 1-18 carbon atoms, nonterminal alkenyl of 4-18 carbon atoms, arylalkyl of 7-25 carbon atoms, or a derivative thereof; x is 0 or 1; R' is alkyl of 1-18 carbon atoms, nonterminal alkenyl of 4-18 carbon atoms, arylalkyl of 7-25 carbon atoms, or a derivative thereof; y is 0, 1, or 2; R" is a branched group having a 2.degree. or 3.degree.

Abstract: An improved process is provided for the preparation of siloxane-oxyalkylene copolymers by a solventless process via hydrosilation of oxyethylene-rich polyethers in the presence of carboxylic acids or carboxylic acid salts as a catalyst modifier. The use of a carboxylic acid or salt prevents acetal formation through the hydroxyl groups of the polyether and/or copolymer. The use of solvent, acetal treatment and solvent stripping steps of the conventional processes are eliminated and accordingly, environmental as well as economic benefits are achieved.

Abstract: A process for preparing vinylaminosilanes in which an aminosilane of the formula HSi(NRR').sub.x (R").sub.3-x is reacted with an alkyne of the formula R"'C.tbd.CH in which R and R" are each saturated or unsaturated aliphatic hydrocarbon radicals or an aromatic hydrocarbon radical, R' and R"' are the same or different and are each hydrogen or R and x is an integer from 1 to 3, in the presence of a platinum hydrosilation catalyst at reaction temperatures above about 180.degree. C.