Polymerization process for aqueous polymer dispersions of vinyl esters and ethylenic monomers

US4532295A · kind A · utility

Assignee

• Wacker Chemie AG · DE

Inventors

• Hartmut Brabetz · Burghausen, DE
• Herbert Eck · Burghausen, DE
• Reinhard Jira · Burghausen, DE
• Heinrich Hopf · Burghausen, DE

Key dates

• Filing date: Jun 28, 1984
• Grant date: Jul 30, 1985
• Expiry date: Jun 28, 2004

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S526/915
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for the preparation of aqueous polymer dispersions comprising polymerizing vinyl esters and up to 50% by weight of the total monomer of compounds with unsaturated ethylenic bonds at a temperature of 10.degree. to 100.degree. C. in the presence of an at least partially water-soluble free-radical initiator and at least one starch member of the group consisting of cyanalkylated starch, hydroxyalkylated starch and carboxyalkylated starch and optionally present conventional adjuvants with the starting mixture containing not more than one-third of the total monomers and the remaining monomers being added by metering during the polymerization, the initiators being at least one member of the group consisting of hydrogen peroxide and organic hydroperoxides in an amount of at least 30 mmol per kg of total monomer mixture and optionally present water-soluble reducing agent and the amount of starch being at least 1% by weight based on the total monomer weight.