Mechanical properties of polymer layers fabricated via hybrid free radical-cationic polymerization of acrylate, epoxide, and oxetane binders

Abstract

This work is aimed at the hybrid free radical-cationic polymerization of acrylate, epoxide, and oxe-tane monomers. Studied hybrid systems were prepared as mixtures of binders polymerizing via freeradical mechanism (pentaerythritol triacrylate, thioacrylate dendritic oligomer) and binders poly-merizing through cationic mechanism (3, 4-epoxycyclohexylmethyl-3, 4-epoxycyclohexanecarboxylateepoxy monomer, bis[1-ethyl(3-oxetanyl)]methyl ether oxetane monomer) in various ratios. As rad-ical and cationic photoinitiators, 2-hydroxy-2-methyl-1-phenyl-propan-1-one and (4-methylphenyl)[4-(2-methylpropyl) phenyl] iodonium hexafluorophosphate, respectively, were used. The process ofpolymerization was monitored using Fourier-transformed infrared spectroscopy giving degree of conver-sion data for each reaction. Cured polymer layers were evaluated in terms of their mechanical properties.Based on experimental data, best mechanical properties (adhesion and flexibility) and the highest degreeof conversion were achieved in hybrid samples containing thioacrylate dendritic oligomer radical binderin combination with (3, 4-epoxycyclohexylmethyl-3, 4-epoxycyclohexanecarboxylate and bis[1-ethyl(3-oxetanyl)]methyl ether (ratio 1:1) cationic monomers.