Grafting of ethylenically unsaturated monomers onto polymers

US6525151B1 · kind B1 · utility

Assignee

• Ciba Specialty Chemicals Corporation · US

Inventors

• Michael Roth · Herbstein, DE
• Rudolf Pfaendner · Rimbach, DE

Key dates

• Filing date: Mar 1, 2001
• Grant date: Feb 25, 2003
• Expiry date: Mar 1, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08L2666/02
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for the preparation of grafted polymers wherein in a first step A) a stable nitroxyl radical is grafted onto a polymer, which step comprises heating a polymer and a stable nitroxyl radical (NO.); and in a second step B) the grafted polymer of step A) is heated in the presence of an ethylenically unsaturated monomer or oligomer to a temperature at which cleavage of the nitroxyl-polymer bond occurs and polymerization of the ethylenically unsaturated monomer or oligomer is initiated at the polymer radical; maintaining said temperature for further polymerization and afterwards cooling down the mixture to a temperature below 60° C. Further subjects are grafted polymers prepared by said process, the use of the polymeric radical initiator and the use of NO radicals for grafting polymers.