Interaction of epoxy and vinyl ethers during photoinitiated cationic polymerization

✍ Scribed by Surésh K. Rajaraman; William A. Mowers; James V. Crivello

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 233 KB
• Volume: 37
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19991101)37:21<4007::aid-pola15>3.0.co;2-8

✦ Synopsis

A kinetic study of the independent and simultaneous photoinitiated cationic polymerization of a number of epoxide and vinyl (enol) ether monomer pairs was conducted. The results show that, although no appreciable copolymerization takes place, these monomers undergo complex interactions with one another. These interactions are highly dependent on the epoxide monomer employed. In all cases, the rate of epoxide ring-opening polymerization is accelerated, whereas that of the vinyl ether is depressed. When highly reactive cycloaliphatic epoxides are subjected to photoinitiated cationic polymerization in the presence of vinyl ethers, the two polymerizations proceed in a sequential fashion, with the vinyl ether polymerization taking place after the epoxide polymerization is essentially complete. A mechanism involving an equilibration between alkoxy-carbenium and oxonium ions has been proposed to explain the results. In addition, the free-radical-induced decomposition of the diaryliodonium salt photoinitiator also takes place, leading to a decrease in the induction period.