Effect of acrylic acid on the mechanical properties of PVA/ starch blend films

Grafting polymers based on acrylic acid (AA) with blend copolymer were synthesized with different ratio of AA (0.125, 0.25 and 0.5% by mass of blend copolymer) using ammonium persulfate as an initiator. The blend copolymer (PVA/S) was prepared by blending poly(vinyl alcohol) (PVA) with starch (S) in ratio (1: 1 wt.%), in presence of glacial acetic acid as a catalyst. The obtained polymers (PVA/S/AA) were characterized by FT-IR, TGA, DTG, SEM and mechanical test. The results showed that the mechanical properties of blend films are strongly dependent on the AA. Moreover, an increase in the ratio of AA in grafted polymers, increase thermal stability, tensile strength and elongation at break.