Photosensitized cationic polymerization of cyclohexene oxide: A mechanistic study concerning the use of pyridinium-type salts

Photoinitiated Metal Free Living Radical and Cationic Polymerizations

“…Following the pioneering work of Crivello describing the use of onium salts as photoinitiators for cationic polymerization of oxiranes and vinyl ethers [39,40], there has been tremendous interest in the development of various photoinitiators [41][42][43][44][45]. Among them, iodonium and sulfonium salts are the most widely used photoinitiators due to their thermal stability, solubility in most of the cationically polymerizable monomers, and efficiency in generating reactive species upon photolysis [46][47][48].…”

Photoacid Generation by Stepwise Two-Photon Absorption: Photoinitiated Cationic Polymerization of Cyclohexene Oxide by Using Benzodioxinone in the Presence of Iodonium Salt

“…As depicted in Scheme 3, the naphthalene radical cations (reaction 9) and/or protonic acids (reaction 10) produced initiate the polymerization in a manner that described for anthracene photosensitization. 15,16 In conclusion, from the results described above it is interfered that cyclic ethers can readily be polymerized by the photolysis of benzodioxinones in the presence of suitable oxidants such as iodonium salts. The process is based on two-photon absorption in which benzophenone is released by the photolysis of benzodioxinone.…”

“…13,14 Among these methods, freeradical-promoted cationic polymerization finds wider application because of availability of a wide range of free radical photoinitiators absorbing at different wavelengths. In addition to the cleavage type photoinitiators, hydrogen abstraction type photoinitiators 15,16 were shown to generate oxidizable electron donor radicals.…”

A study of the elemental reactions involved in the initiation of the polymerization of tetrahydrofuran induced by the photosensitization of a triphenylsulphonium salt by perylene

“…There is growing interest in polymerizations initiated by external stimulation, such as photoirradiation or highenergy radiation, 1 and much effort has been devoted to develop systems that may initiate the polymerization processes through cationic 2,3,4 and radical mechanisms. 5,6 Cationic polymerization is widely applicable for both vinyl and ring-opening polymerizations giving place to many studies of both academic and industrial interests.…”

“…Photosensitized cationic polymerizations with compounds absorbing at longer wavelengths attract particular interest since the triggering of the initiation may be extended beyond the UV region. 4 The ring-opening polymerizations of several oxirane monomers have been studied quite frequently and have been known for a long time. Direct and photosensitized 11 irradiation of onium salts 12,13 can generate strong Brønsted acids that will begin the polymerization processes.…”