Selective Controlled/Living Photoradical Polymerization of Glycidyl Methacrylate, Using a Nitroxide Mediator in the Presence of a Photosensitive Triarylsulfonium Salt

Polymers

关键词: photopolymerization;    controlled/living radical polymerization;    vinyl group;    glycidyl methacrylate;    oxirane ring;    4-methoxy-2;    2;    6;    6-tetramethylpiperidine-1-oxyl;    cationic ring-opening photopolymerization;    (4-tert-butylphenyl)diphenylsulfonium triflate;    (2RS;    2'RS)-azobis(4-methoxy-2;    4-dimethylvaleronitrile);   

DOI  :  10.3390/polym4031580

来源: mdpi

【 摘 要 】

The controlled/living photoradical polymerization of glycidyl methacrylate (GMA) was attained using 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl (MTEMPO) as the mediator and (2RS,2'RS)-azobis(4-methoxy-2,4-dimethylvaleronitrile) as the initiator in the presence of (4-tert-butylphenyl)diphenylsulfonium triflate (^tBuS). Whereas the polymerization in the absence of MTEMPO yielded a gel-containing polymer, the MTEMPO-mediated polymerization produced poly(GMA) bonded at the vinyl site, and retained the oxirane ring structure. No occurrence of the cationic ring-opening photopolymerization of the oxirane ring even in the presence of the photosensitive onium salt indicated that ^tBuS served as the photoelectron transfer agent between MTEMPO in their excited states at the propagating chain end. The resulting polymers had comparatively narrow molecular weight distributions of M_w/M_n = 1.46–1.48. The living nature of the MTEMPO-mediated polymerization was confirmed on the basis of a linear increase in the conversion-molecular weight plots and gel permeation chromatography (GPC) analysis.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland.