GB765551A - Manufacture of polysiloxane condensation products - Google Patents

Abstract

A condensation product, suitable for lacquers, impregnating agents or mouldings, is made by reacting an organopolysiloxane containing -SiH groups with a polyhydric alcohol or a partially esterified or etherified polyhydric alcohol or a mixture thereof, preferably in the presence of a catalyst and at a raised temperature. There may be added and reacted at any desired stage an aliphatic or aromatic polycarboxylic acid, or anhydride thereof, e.g. phthalic acid or anhydride and maleic acid, a fatty oil, e.g. castor, wood or tall oil, a saturated or unsaturated fatty acid of at least 12 carbon atoms, e.g. oleic acid, a high molecular weight hydroxy carboxylic acid, e.g. ricinoleic acid, a resin acid, e.g. abietic and pimaric acids, a synthetic resin modified with any of the aforementioned compounds, a trialkylalkoxysilane or a trialkylsilanol, e.g. trimethyl-ethoxy silane or trimethyl-silanol. Additives such as driers, softening agents, stabilizers and synthetic resins modified in known manner by esterification or etherification may also be added at any desired stage. Catalysts specified are caustic soda and potash and alcoholates, acids and aluminium acetyl-acetonate. In examples the polysiloxane obtained by cohydrolysing dimethyldichloro-and methyldichloro-silanes is reacted with (1) oleic monoglyceride, (2) glycerine and oleic acid, and (3) pentaerythrite and oleic acid; (4) the product of Example (3) is further reacted with phthalic anhydride.