Premium
Photoinduced Cross‐Linking of Dynamic Poly(disulfide) Films via Thiol Oxidative Coupling
Author(s) -
Feillée Noémi,
Chemtob Abraham,
Ley Christian,
CroutxéBarghorn Céline,
Allonas Xavier,
Ponche Arnaud,
Le Nouen Didier,
Majjad Hicham,
Jacomine Léandro
Publication year - 2016
Publication title -
macromolecular rapid communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.348
H-Index - 154
eISSN - 1521-3927
pISSN - 1022-1336
DOI - 10.1002/marc.201500459
Subject(s) - photopolymer , oligomer , polymerization , thiol , covalent bond , elastomer , polymer chemistry , photochemistry , materials science , chemistry , oxidative coupling of methane , organic chemistry , polymer , catalysis
Initially developed as an elastomer with an excellent record of barrier and chemical resistance properties, poly(disulfide) has experienced a revival linked to the dynamic nature of the S–S covalent bond. A novel photobase‐catalyzed oxidative polymerization of multifunctional thiols to poly(disulfide) network is reported. Based solely on air oxidation, the single‐step process is triggered by the photodecarboxylation of a xanthone acetic acid liberating a strong bicyclic guanidine base. Starting with a 1 μm thick film based on trithiol poly(ethylene oxide) oligomer, the UV‐mediated oxidation of thiols to disulfides occurs in a matter of minutes both selectively, i.e., without overoxidation, and quantitatively as assessed by a range of spectroscopic techniques. Thiolate formation and film thickness determine the reaction rates and yield. Spatial control of the photopolymerization serves to generate robust micropatterns, while the reductive cleavage of S–S bridges allows the recycling of 40% of the initial thiol groups.