Photopolymerization of commercially available bisphenol A epoxy diacrylates with bis[4(2-hydroxy-3-acryloyloxypropoxy)phenyl]sulfide (BES-DA)a monomer synthesized by our group in previous study was carried out. As this compound is solid at room temperature in its polymerization reactive diluent N-vinyl-2-pyrrolidone, which is also comonomer, has been applied. As a photoinitiator, 2-hydroxy-2-methyl-1-phenylpropan-1-one (Darocur 1173) was used. Thermal and mechanical properties of the obtained compositions were studied. The results show that thermal properties of both epoxy diacrylates improve with the increasing concentration of BES-DA. The addition of N-vinyl-2-pyrrolidone causes decrease of their storage moduli and glass transition temperatures. Simultaneously, it allows to increase the conversion of double bonds. (C) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012