Continuous bulk polymerization process

US4141934A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Frank Wingler · Leverkusen, DE
• Adolf Schmidt · Adelsheim, DE
• Lothar Liebig · Leverkusen, DE
• Gerd Wassmuth · Leverkusen, DE

Key dates

• Filing date: Mar 22, 1976
• Grant date: Feb 27, 1979
• Expiry date: Mar 22, 1996

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F212/10
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Copolymers of PA1 A 22 to 96 mol-% of styrene and/or .alpha.-methyl styrene, PA1 B 0 to 78 mol-% of at least one monoolefinically unsaturated monomer containing nitrile groups, and PA1 C 0 to 50 mol-% of at least one monoolefinically unsaturated monomer different from A or B are obtained by continuous bulk polymerization in a homogeneous liquid phase, in several process stages, in one or more different temperature ranges and in the presence of one or more initiators with different dissociation times in each temperature range and under pressures of from 1 to 20 bars. In first stage the monomers are copolymerized with backmixing up to a conversion of from 10 - 60 mol-% in an ideally mixed tank reactor and then after optionally additional addition of further parts of monomers copolymerization is continued with backmixing in a completely flooded, self-cleaning polymerization kneader up to a residual monomer content of from 10-50 mol-%. Residual monomers are continuously removed from the copolymer up to a content of less than 0.5% by weight based on the copolymer. The process according to the invention provides uniform, compatible, homogeneous products which are free from gel-like parti…