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Updated: May 12, 2025

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
Mechanistic Study of Substituent Effect on Photoinduced O-C Bond Activation in Polycarbonate
Xiao Huang1, Yuuichi Orimoto2, Yuriko Aoki1,2
1Department of Interdisciplinary Engineering Sciences, Chemistry and Materials Science, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga Park, Fukuoka 816-8580, Japan.
Abstract:
Photodegradation of polycarbonate (PC) is investigated based on quantum chemical methods with PC models to clarify the effect of substituents at different positions of phenyl rings on the carbonate O-C bond cleavage. Compared to the results without substituents on phenyl rings, the breakage of the carbonate O-C bond is promoted or suppressed when the electron-donating or electron-withdrawing group is placed on the meta- or ortho-positions of the gem-dimethyl groups of phenyl rings, respectively. Moreover, the promotion and suppression of carbonate O-C bond scission are more significant if the substituents are located on the ortho-positions of the gem-dimethyl groups.
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