Free radical polymerisation process

US5602220A · kind A · utility

Assignee

• Zeneca Limited · GB

Inventors

• David M. Haddleton · Kenilworth, GB
• Andrew Victor Graham Muir · Leatherhead, GB

Key dates

• Filing date: Feb 9, 1996
• Grant date: Feb 11, 1997
• Expiry date: Feb 9, 2016

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F10/00
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Process for the free-radical polymerisation of olefinically unsaturated monomer(s) using a free-radical initiator, wherein said polymerisation is performed in the presence of a compound for effecting molecular weight control, said molecular weight control compound being selected from Cobalt II chelates of the following formulae I, II and III: ##STR1## wherein: x and y are independently 2 to 5; PA0 each R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is independently selected from H, C1-C12 alkyl, optionally substituted aryl, OR.sup.5 where R.sup.5 is C1 to C12 alkyl or optionally substituted aryl, CO.sub.2 R.sup.5, SO.sub.3 H, C(.dbd.O)R.sup.5, CO.sub.2 H, NO.sub.2, OH, NR.sup.5.sub.2, NH.sub.2, NHR.sup.5, SR.sup.5, SH, CN, SO.sub.3 R.sup.5, halogen, 2-furyl and 3-furyl; PA0 each X is independently selected from (CR.sup.6.sub.2).sub.n, (CR.sup.6.sub.2 O).sub.n, optionally substituted o-phenylene, and optionally substituted 1,8-naphthylene, where each R.sup.6 is independently selected from H and C1 to C12 alkyl, and n is 1 to 10; PA0 and wherein said cobalt chelates of formulae I and II possess a positive charge of 2 and are associated with an anion or anions for balancing the positive charge…