Polymerization of chloroprene

US4786698A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Rudiger Musch · Bensberg, DE
• Eberhard Muller · Cologne, DE
• Peter Wendling · Leverkusen, DE
• Wolfgang Konter · Neuss, DE
• Gerhard Hohmann · Leverkusen, DE

Key dates

• Filing date: Dec 15, 1987
• Grant date: Nov 22, 1988
• Expiry date: Dec 15, 2007

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F36/18
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Gel-free polychloroprene is obtained, at high monomer conversions, using a polymerization initiator comprising sodium dithionite or a mixture of sodium dithionite with formamidinesulphinic acid or with potassium peroxydisulphate or with formamidinesulphinic acid and potassium peroxodisulphate or with potassium peroxodisulphate and sodium anthraquinon-.beta.-sulphonate or with formamidinesulphinic acid and potassium peroxodisulphate and sodium anthraquinone-.beta.-sulphonate, and in the presence of oxygen and a chain transfer agent when 30 to 90% of the initiator is present at the commencement of polymerization and the remainder is added in portions during the polymerization, only further sodium dithionite being added at a conversion >60% in the case of an initiator combination, and when 20 to 80% by weight of the total amount of chain transfer agents is present before or at the commencement of polymerization and the remaining amount is added in one or more parts at monomer conversions of greater than 20%.