The new monomer N'-(beta-methacryloyloxyethyl)-2- pyrimidyl-(p-benzyloxycarbonyl)aminobenzenesulfonamide (MPBAS) (M-1) is synthesized using sulfadiazine as parent compound. It could be homopolymerized and copolymerized with N-phenyl maleimide (NPMI) (M-2) by radical mechanism using AIBN as initiator at 60 degrees C in dimethylformamide. The new monomer MPBAS and polymers were identified by IR, element analysis and H-1 NMR in detail. The monomer reactivity ratios in copolymerization were determined by YBR method, and r(1) (MPBAS) = 2.39 +/- 0.05, r(2) (NPMI) = 0.33 +/- 0.02. In the presence of ammonium formate, benzyloxycarbonyl groups could be broken fluently from MPBAS segments of copolymer by catalytic transfer hydrogenation, and the copolymer with sulfadiazine side groups are recovered.