Process for the preparation of stable water-in-oil emulsions of hydrolyzed polymers of N-vinyl amides and the use thereof

US5739190A · kind A · utility

Assignee

• BASF SE

Inventors

• Heinrich Hartmann · Schifferstadt, DE
• Karl-Heinrich Schneider · Kleinkarlbach, DE
• Walter Denzinger · Speyer, DE
• Claudia Nilz · Rödersheim-Gronau, DE
• Dietmar Monch · Weinheim, DE

Key dates

• Filing date: Nov 21, 1996
• Grant date: Apr 14, 1998
• Expiry date: Nov 21, 2016

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02W10/37
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for the preparation of a stable water-in-oil emulsion of a hydrolyzed polymer of an N-vinyl amide of the formula ##STR1## in which R and R.sup.1 denote H or C.sub.1 -C.sub.6 alkyl, by the polymerization of a compound of the formula I alone or in admixture with another ethylenically unsaturated monomer in the presence of a polymerization initiator and emulsifier in the form of a water-in-oil emulsion, to form a water-in-oil polymeric emulsion, followed by hydrolysis of the polymer in the form of the water-in-oil polymeric emulsion in the presence of an acid or base and from 1 to 30 wt %, based on the polymer, of an emulsifier, the emulsifier used being a mixture of PA1 (a) from 5 to 95 wt % of a block or graft copolymer of the structure (A-B)m, (A)-B or (B)-A, in which in each case PA1 (a) from 5 to 95 wt % of a block or graft copolymer of the structure (A-B).sub.m, (A).sub.n B or (B).sub.n A, in which in each case PA2 A is a hydrophobic homopolymer or copolymer having a degree of polymerization of at least 3, PA2 B is a hydrophilic homopolymer or copolymer having a degree of polymerization of at least 3, PA2 m is equal to or greater than 1, and PA2 n is equal to or greate…