Bio-based polymer networks by thiol-ene photopolymerizations of allyl-etherified eugenol derivatives

摘要

Allyl-etherified eugenol (AEG) was synthesized by the reaction of eugenol and allyl bromide in the presence of sodium hydroxide. 1,3-Diallyl-4-allyloxy-5-methoxybenzene (DAEG) was also synthesized by a similar allyl-etherification reaction of 2,4-diallyl-6-methoxyphenol (rAEG) which was produced by the Claisen rearrangement of AEG. Thiol-ene photopolymerization of AEG or DAEG with pentaerythritol-based primary tetrathiol (pS4P), pentaerythritol-based secondary tetrathiol (S4P) or isocyanurate-based secondary trithiol (S3I) at allyl/SH 1/1 produced photo-cured resins (AEG-pS4P, AEG-S4P, AEG-S31, DAEG-pS4P, DAEG-S4P or DAEG-S3I). Glass transition temperature of every photo-cured resin was in the range from 4 to 9 degrees C. AEG-pS4P and DAEG-pS4P displayed higher 5% weight loss temperatures (378.3 and 367.9 degrees C, respectively) than the other cured resins (351-344 degrees C). DAEG-pS4P, AEG-pS4P and AEG-S3I displayed the highest tensile modulus (32.9 MPa), strength (0.98 MPa) and elongation at break (58.7%) among all the photo-cured films, respectively. (C) 2014 Elsevier Ltd. All rights reserved.