In this study, copolymers of styrene and poly(ethylene glycol)methyl ether methacrylate (MPEG) were synthesized and their properties were analyzed. Copolymer poly (styrene-copoly( ethylene glycol)methyl ether methacrylate) (ST-co-M-PEG) was synthesized with initial molar ratios of monomers in the reaction mixture (S80/M20, S60/M40, S50/M50, S20/M80 where S is styrene and M is M-PEG). Total monomer concentration in all mixtures is 1 mol/dm^3. Tert-butyl peroxy 2-ethyl-hexanoate (Trigonox 21) was used as initiator. Two syntheses were performed for each ratio, one to lower conversions lasting 3 hours and the other to high conversions lasting 24 hours. Due to the swelling and gelation of the polymer, it was not possible to do the synthesis in the dilatometer to conversions lower than 10% and because of that copolymerization reactivity ratios could not be determined. Composition of the polymer was determined by FTIR infra-red technique. Copolymers with longer reaction time contain more sryrene. Copolymers with more ethylene glycol methacrylate form a gel and retain the solvent, and because of that these polymers are difficult to dissolve, therefore analysis by NMR and GPC techniques was not possible. Thermal properties of synthesized copolymers were determined with differential scanning calorimetry (DSC). Copolymers with more M-PEG have higher enthalpies of crystallization and melting.