Preparation of copolymers of monoethylenically unsaturated mono- and dicarboxylic acids and anhydrides

US4725655A · kind A · utility

Assignee

• BASF SE

Inventors

• Walter Denzinger · Speyer, DE
• Heinrich Hartmann · Schifferstadt, DE
• Wolfgang Trieselt · Ludwigshafen, DE
• Albert Hettche · Heßheim, DE
• Rolf Schneider · Burgstetten, DE
• Hans-Juergen Raubenheimer · Ketsch, DE

Key dates

• Filing date: Oct 16, 1986
• Grant date: Feb 16, 1988
• Expiry date: Oct 16, 2006

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F222/02
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Copolymers which contain, as copolymerized monomer units, monoethylenically unsaturated mono- and dicarboxylic acids are prepared by a process in which PA0 (a) from 10 to 60% by weight of a monoethylenically unsaturated dicarboxylic acid of 4 to 6 carbon atoms, its salt and/or, if appropriate, its anhydride, PA0 (b) from 90 to 40% by weight of a monothylenically unsaturated monocarboxylic acid of 3 to 10 carbon atoms and/or its salt and PA0 (c) from 0 to 20% by weight of another, carboxyl-free monoethylenically unsaturated monomer which is copolymerizable with (a) and (b), the percentages being based on the sum of the monomers, are polymerized in the presence of from 0.5 to 5% by weight of a water-soluble free-radical-forming initiator in an aqueous medium at from 60.degree. to 150.degree. C., and, if appropriate, their anhydride groups are hydrolyzed, the monomers (a) and (b) being employed in a form such that from 20 to 80% of their amount is neutralized during the polymerization reaction, wherein the copolymerization is carried out continuously in a reactor cascade comprising several reactors, and an aqueous solution of a pre-prepared copolymer of (a), (b) and, if appropriate, (…