Abstract: In this paper, the graft copolymer LDPE-g-MAH was prepared with LDPE, monomers of malefic anhydride via free radical polymerization. The copolymer was characterized by IR. Then the crystal morphology of copolymer was investigated by polarizing microscope. The differential scanning calorimetry researching was used to study the isothermal and non-isothermal crystallization of LDPE-g-MAH and LDPE. Isothermal crystallization tests were performed at 92℃, 93℃, 94℃, and 95℃. The Avrami equation was used to investigate the isothermal crystallization.,then obtained the isothermal crystallization parameters. In this test, it was found that the effect of crystallization temperature on the isothermal crystallization kinetics is obviously. For non-isothermal crystallizations, crystallizations were performed at cooling rates 5, 10, 15, and 30 ℃/min respectively. In the case of non-isothermal crystallization, it was found that the Ozawa analysis was rather inapplicable for the graft copolymer LDPE-g-MAH and LDPE. In contrast, the modified Avrami method, as well as the method proposed by Mo was applied giving satisfactory results.
Keywords:PE;MAH; Copolymer; Crystallization kinetics;