Effects of polyethylene-grafted maleic anhydride (PE-gMA) on thermal properties, morphology, and tensile properties of low-density polyethylene (LDPE) and corn starch blends

The effects of polyethylene-grafted maleic anhydride (PE-g-MA) on the thermal properties, morphology, and tensile properties of blends of low-density polyethylene (LDPE) and corn starch were studied with a differential scanning calorimeter (DSC), scanning electron microscope (SEM), and Instron Universal Testing Machine, respectively. Corn starch-LDPE blends with different starch content and with or without the addition of PE-g-MA were prepared with a lab-scale twin-screw extruder. The crystallization temperature of LDPE-corn starch-PE-g-MA blends was similar to that of pure LDPE but higher than that of LDPE-corn starch blends. The interfacial properties between corn starch and LDPE were improved after PE-g-MA addition, as evidenced by the structure morphology revealed by SEM. The tensile strength and elongation at break of corn starch-LDPE-PE-g-MA blends were greater than those of LDPE-com starch blends, and their differences became more pronounced at higher starch contents. (C) 2003 Wiley Periodicals, Inc.