Process for the production of siliconfunctional polyorganosiloxanes

Abstract

Abstract In the production of linear and branched equilibrated acyloxy-containing organopolysiloxanes by reacting a chlorosilane of the formula R.sub.a R'.sub.b SiCl.sub.(4-a-b) in which a is 0,1,2 or 3, b is 0,1,2 or 3, and a+b≦3, or a partial hydrolysate thereof, with at least one organosiloxane containing the components R.sub.2 R"--SiO.sub.1/2, R R"--SiO, R"--SiO.sub.3/2 and SiO.sub.2 in which R and R" each independently is H or an optionally halogen- or cyano-substituted monovalent hydrocarbon radical having up to 12 carbon atoms, and R" is Cl, OH, H or an optionally halogen- or cyano-substituted monovalent hydrocarbon radical having up to 12 carbon atoms, in the presence of an equilibration catalyst, the improvement which comprises employing as the equilibration catalyst a salt of a fluorinated alkane sulphonic acid plus a monobasic carboxylic acid, the total number of Si--Cl groups exceeding the total number of Si--OH groups in the reactants and the monobasic carboxylic acid being present in at least about 1.1 times the molar amount of silicon-bound Cl atoms. Advantageously the salt of the fluorinated alkane sulphonic acid is the potassium salt of octafluorobutane sulphonic acid and it is used in about 0.3 to 0.7% by weight of the silicon compound reactants. The equilibration is effected at a temperature up to about 135° C., and the monobasic carboxylic acid is acetic acid.

Inventors

• 👤 Armand DE Montigny
• 👤 Hans Niederprum

Bibliographic Details