A styrene-based monomer having a five-membered cyclic dithiocarbonate structure, 4-vinylbenzyl 1,3-oxathiolane-2-thione-5-ylmethyl ether (VBTE), was synthesized from 4-vinylbenzyl glycidyl ether (VBGE) and carbon disulfide in the presence of lithium bromide in 86% yield. Radical polymerization of VBTE in dimethyl sulfoxide by 2,2-azobisisobutyronitrile was carried out at 60 degrees C to afford the corresponding the polymer, polyVBTE, in 64% yield. PolyVBTE with number-averaged molecular weight higher than 31,000 was obtained. The glass transition temperature (Tg) and 5 wt % decomposition temperature (Td5) of the polyVBTE were evaluated to be 66 and 264 degrees C under nitrogen atmosphere by differential scanning calorimetry and thermal gravimetry analysis, respectively. It was confirmed that a polymer consisting of the same VBTE repeating unit could also be obtained via polymer reaction, that is, a lithium bromide-catalyzed addition of carbon disulfide to a polyVBGE prepared from a radical polymerization of VBGE. Copolymerization of VBTE and styrene with various compositions efficiently gave copolymers of VBTE and styrene. (c) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013