Preparation of water-soluble polymer powders and their use

US4670524A · kind A · utility

Assignee

• BASF SE

Inventors

• Karlheinz Messmer · Bad Dürkheim, DE
• Karl Hennig · Heßheim, DE
• Walter Denzinger · Speyer, DE
• Albert Hettche · Heßheim, DE
• Wolfgang Trieselt · Ludwigshafen, DE
• Hans-Juergen Raubenheimer · Ketsch, DE

Key dates

• Filing date: Apr 29, 1986
• Grant date: Jun 2, 1987
• Expiry date: Apr 29, 2006

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S526/909
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Water-soluble polymer powders are prepared by polymerizing water-soluble ethylenically unsaturated monomers in a powder bed in the presence of polymerization initiators and water while maintaining the powder state, removing the heat of polymerization by distilling off water and circulating the reaction mixture, by a process in which water-insoluble organic peroxides which are liquid at 20.degree. C. are used alone or as a mixture with up to 50% by weight, based on the initiator mixture, of water-soluble, organic azo initiators and/or water-insoluble solid peroxy-containing compounds, as polymerization initiators.