Low molecular weight polymers of acrylic esters

US4983760A · kind A · utility

Assignee

• BASF SE

Inventors

• Georg Bobar · Bad Dürkheim, DE
• Klaus Schnell · Neustadt, DE
• Gerd Schroeder · Schifferstadt, DE
• Eckehardt Wistuba · Bad Dürkheim, DE

Key dates

• Filing date: Jan 8, 1990
• Grant date: Jan 8, 1991
• Expiry date: Jan 8, 2010

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F20/12
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Low molecular weight polymers of acrylic esters which are suitable for use as external plasticizers in coated compositions on a synthetic resin basis are obtainable by subjecting PA1 (a) from 80 to 100% by weight of at least one acrylic ester of C.sub.1 -C.sub.8 -alkanol (monomer I) and PA1 (b) 0 to 20% by weight of one or more other copolymerizable monomers (monomer II) to a free radical polymerization in a solution in isopropanol in a pressure vessel at 130.degree.-140.degree. C. by introducing first from 70 to 95% by weight of a solvent and adding the remainder of the polymerization batch continuously over 3-7 hours in separate portions of which one contains the monomers and, after the polymerization has ended, distilling off the solvent under reduced pressure, the weight proportion of solvent being 5-15% by weight based on the monomers, the weight proportion of initiator being 0.5-3% by weight based on the monomers, and the half-life of the initiator at the polymerization temperature being from 10 seconds to 3 hours.