Tetra-functional epoxy-acrylate as crosslinker for UV curable resins: Synthesis, spectral, and thermo-mechanical studies

UV-curable tetra-functional epoxy acrylate (EA4) was newly synthesized using 4,4′-methylenebis(N,N-diglycidylaniline). Effects of reaction temperature and epoxy/acrylic acid molar ratios on the reaction conversion were investigated. The conversion of epoxy to ester group was monitored by FTIR spectroscopy and the relative concentration of epoxy value and conversion of the reactions were calculated from FTIR data, in different intervals of the reaction time. EA4 curing under UV irradiation was studied, and the physicochemical characteristic of the cured resin was determined. DMTA, TGA and mechanical properties of the casted films were evaluated. Moreover, studies on effect of the synthesized EA4 content on properties of conventional epoxy acrylate (EA2) were carried out. According to TGA and DMTA studies, the UV-cured blend films of EA2 containing ≤9% EA4 presented film homogeneity, and improved thermal and mechanical properties. Thus, it can be used as a crosslinking agent in UV-curable formulations.