Process for the preparation of organopolysiloxane resins

US5359022A · kind A · utility

Assignee

• Wacker Chemie AG · DE

Inventors

• Konrad Mautner · Burghausen, DE
• Richard Weidner · Burghausen, DE
• Helmut Oswaldbauer · Stubenberg, DE

Key dates

• Filing date: Nov 3, 1993
• Grant date: Oct 25, 1994
• Expiry date: Nov 3, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G77/06
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for preparing an organopolysiloxane resin, which comprises reacting in a first stage at least one silane of the formula EQU R.sub.a Si(OR.sup.1).sub.4-a (I) in which a is 0, 1, 2 or 3, R is a monovalent organic radical, and/or a partial hydrolyzate thereof, with the proviso that at least one silane of formula (I) in which a is equal to 0 or 1, and/or a partial hydrolyzate thereof, is employed, and, if appropriate, an organo(poly) siloxane with water in the presence of acid and, if appropriate, other substances, in a second stage reacting the reaction mixture obtained from the first stage in the presence of base and, if appropriate, other substances, and in a third stage adding with stirring, the reaction mixture obtained in the second stage into water, and if appropriate mixed with additives.