Study of graft copolymerization of N-maleamic acid-chitosan and butyl acrylate by gamma-ray irradiation.

N-maleamic acid-chitosan was synthesized and characterized by Fourier transform infrared spectra analysis (FT-IR) and 1H NMR. The graft copolymerization of N-maleamic acid-chitosan and butyl acrylate (BA) in acetic acid aqueous solution was investigated, using the gamma-ray of 60Co gamma-irradiation method. DSC (differential scanning calorimetry) trace of N-maleamic acid-chitosan-g-PBA has a glass-transition temperature (Tg) at -42 degrees C. The thermal stabilities of the graft copolymer were studied by the thermal gravimetric analysis (TGA). The effect of synthesis variables in the graft copolymerization have been discussed in the light of grafting efficiency, grafting percentage, and homopolymer percentage. Increasing grafting percentage was observed when the monomer concentration and total dose were increased or when the reaction temperature was decreased.