Thioketone-Mediated Polymerization of Butyl Acrylate: Controlling Free-Radical Polymerization via a Dormant Radical Species

✍ Scribed by Thomas Junkers; Martina H. Stenzel; Thomas P. Davis; Christopher Barner-Kowollik

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 269 KB
• Volume: 28
• Category: Article
• ISSN: 1022-1336
• DOI: 10.1002/marc.200600885

✦ Synopsis

Abstract

It is demonstrated by experiment and simulation that the commercially available thioketone 4,4‐bis(dimethylamino)thiobenzophenone is capable of controlling AIBN‐initiated bulk butyl acrylate polymerization at 80 °C. On the basis of molecular weight data and from monomer conversion versus time curves, the associated rate parameters are estimated. The addition rate coefficient, k~ad~, for the reaction of a propagating chain with the thioketone is close to 10^6^ L · mol^−1^ · s^−1^ and the fragmentation rate coefficient, k~frag~, is around 10^−2^ s^−1^ giving rise to large equilibrium constants in the order of 10^8^ L · mol^−1^. Furthermore, cross‐ and self‐termination of the dormant radical species are identified to be operational.

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