English Abstract
Photodegradation of Diene Polymers Sensitized by Quinones.
Masahito OKUDERA
Yuuji KAWAMURA
Yasuhiro SHIBATA
Hiroaki KOUZAI
Department of Applied Material and Life Science, Kanto Gakuin University, Kanagawa-ku, Yokohama, Japan
Nippon Gomu Kyokaishi,(2005),78(11),419-423 Original Paper in Japanese


Abstract
It was confirmed that photodegradation of diene polymers in solutions is accelerated by the addition of quinones or benzophenone as a sensitizer. The viscosities of the polymer solutions were markedly lowered by the degradation with UV-irradiation when the sensitizer was added. Especially, high promotion effects on the degradation of diene polymers were observed by the addition of polyaromatic quinone, such as anthraquinone. The decrease in the solution viscosities, along with FT-IR and H-NMR of the irradiated polymers, indicates that the degradation of the diene polymers proceeds through the auto-oxidation mechanism. It is inferred that the effects of quinone groups on the diene polymer degradation result from hydrogen abstraction by quinone groups in excited state.

(Received on March 10, 2005)

(Accepted on September 16, 2005)

Keywords:
Diene polymer, cis-1,4-Polyisoprene, Photodegradation, Sensitizer, Quinones, Benzophenone, Auto-oxidation system
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