Process for the preparation of SiOC-linked, linear polydimethylsiloxane-polyoxyalkylene block copolymers and their use

US7825209B2 · kind B2 · utility

Assignee

• EVONIK GOLDSCHMIDT GMBH · DE

Inventors

• Wilfried Knott · Essen, DE
• Klaus-Dieter Klein · Oberkochen, DE
• Rüdiger Landers · Essen, DE
• Dagmar Windbiel · Essen, DE

Key dates

• Filing date: Dec 14, 2007
• Grant date: Nov 2, 2010
• Expiry date: Nov 26, 2028

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08L83/12
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The invention relates to a process for the preparation of SiOC-linked, linear polydimethylsiloxane-polyoxyalkylene block copolymers having (AB) repeat units, via reaction of one or more polyetherdiols with a stoichiometric excess of α,ω-dihydropolydimethylsiloxanes and at least one tertiary amine as catalyst, which comprises, after completed reaction of the alcohol component, continuing the reaction in the presence of small amounts of water until no remaining ≡Si(H) groups are detectable by a gas-volumetric method.