Effect of degree of crystallinity on mechanical properties of chitosan-g-poly(vinyl alcohol) copolymer

Chitosan grafted poly(vinyl alcohol) (PVA) with high crystallinity was prepared by eerie ammonium nitrate (CAN) as initiatiator to use membrane. The copolymer membrane was crosslinked by chitosan-g-PVA copolymer submerging into 1% glutaraldehyde aqueous solution. The water contents of copolymer and crosslinked copolymer were highly dependent on pH, especially between 4 and 7. The water content of crosslinked copolymer was larger than that of copolymer. Comparing the degree of crystallinity and mechanical properties according to the various conditions, the degree of crystallinity of copolymer membrane was increased with increasing grafting percentage and curing temperature. Tensile strength and Young's modulus of copolymer membrane were increased but elongation was decreased with increasing grafting percentage. Tensile strength, Young's modulus, and elongation of copolymer membrane were increased with increasing curing temperature but mechanical properties of crosslinked copolymer membrane were mostly constant with grafting percentage and curing temperature.