Process for preparing SiC-bonded polyethersiloxanes

US10526454B2 · kind B2 · utility

Assignee

• EVONIK DEGUSSA GMBH · DE

Inventors

• Wilfried Knott · Essen, DE
• Dagmar Windbiel · Essen, DE

Key dates

• Filing date: May 14, 2018
• Grant date: Jan 7, 2020
• Expiry date: Jul 26, 2038

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G77/12
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for preparing SiC-bonded polyethersiloxanes by precious metal-catalysed addition of olefinically unsaturated polyethers onto siloxanes having SiH groups is described, wherein, prior to commencement of reaction, the siloxane having SiH groups is mixed with an olefinically unsaturated polyether and with a polyethersiloxane by stirring, and then contacted with a precious metal catalyst and optionally further additives, and the SiC bond formation reaction is conducted up to an SiH conversion, determined by gas-volumetric means, of at least 97%.