Copolymers and their use as drilling aids

US6380137B1 · kind B1 · utility

Assignee

• Clariant Corporation · DE

Inventors

• Karl Heinz Heier · Frankfurt am Main, DE
• Roman Morschhäuser · Mainz, DE
• Aranka Tardi · Neuberg, DE
• Susanne Weber · New York, US
• Gernold Botthof · Kirtorf, DE

Key dates

• Filing date: Mar 2, 2000
• Grant date: Apr 30, 2002
• Expiry date: Mar 2, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09K8/24
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The invention provides water-soluble copolymers without crosslinking, consisting of the following components:A 5-95% by weight of bivalent structural units derived from acrylamidopropenylmethylenesulfonic acid or its salts,B 1-45% by weight of bivalent structural units derived from open-chain N-vinylamides,C 1-45% by weight of bivalent structural units derived from cyclic N-vinyl-substituted amides,and if desiredD 0-50% by weight of a further comonomer selected from the group consisting of acrylamide, acrylic acid and acrylonitrile,the components A to C and, if present, D adding up to 100% by weight.