Method for the production of branched polymerizates

US5693717A · kind A · utility

Assignee

• Roehm GmbH Chemische Fabrik · DE

Inventors

• Martina Pfirmann · Griesheim, DE
• Werner Siol · Pfungstadt, DE
• Klaus Koralewski · Riedstadt, DE
• Michael Wicker · Seeheim-Jugenheim, DE

Key dates

• Filing date: Jul 1, 1996
• Grant date: Dec 2, 1997
• Expiry date: Jul 1, 2016

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C10N2040/28
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

A method for producing branched polymerizates by radical polymerization of monomers in two stages comprising in a first stage, adding 10 to 500 parts by weight of at least one monomer M.sub.1 and 0.1 to 20 parts by weight of a mercaptan with an olefinic, radically polymerizable double bond RM as a molecular weight regulator, and polymerizing said at least one monomer M.sub.1 mercaptan RM to form a copolymer MM.sub.1 in the presence of at least one polymerization initiator and 0 to 100 parts by weight of an inert, non-aqueous solvent, which completely dissolves the monomer M.sub.1, the mercaptan RM and the copolymer MM.sub.1, where the polymerizable double bonds of M.sub.1 and RM have a reactivity, expressed by a copolymerization parameter r, between 0.1 and 10, and in a second stage, adding 10 to 2000 parts by weight of a monomer M.sub.2 and 0.01 to 10 parts by weight of a saturated molecular weight regulator, and optionally, an inert, non-aqueous solvent, to the reaction mixture formed in the first stage, and polymerizing in the presence of at least one polymerization initiator to form a branched polymerizate. Branched polymerizates made by the method.