Study Of Degradation Of Polyethylene Film

In this paper, to meet the intelligentized requirements of the agricultural mushrooms bag, polyethylene/poly lactic acid, polyethylene/starch composite materials were prepared by melt blending, and the thin film was prepared by means of film blowing. Polyethylene/poly lactic acicl/montmorillonite, polyethylene/poly lactic acid/polyethylene-maleic-anhydride, polyethylene/starch/polyethylene-maleic anhydride compound film were prepar-ed, and add non-polar particles and bulking agent in order to further improve the perform-ancee of thin films. The mechanical properties, processing properties, crystalline abilities degradable performance of composite films and the changes of mechanical properties after degradation were studied through the mechanical properties tester, melt flow rate tester, differential scanning calorimetry, scanning electron microscopy and other means. The results showed that:The mechanical properties of polyethylene/poly lactic acid composite films, polyethy-lene/starch composite films first increased and then decreased with the increasing of the content of degradable material. The degradation performance of the composite film contained starch was the best one, the mechanical property after degradation overall declined and so did the crystal degree.To prepare polyethylene/poly lactic acid/montmorillonite composite film, we add inorganic particles to polyethylene/poly lactic acid, its mechanical properties had more substantial increasement compared to polyethylene/poly lactic acid composite film, and there was a first decreasing then rapidly increasing trend in the melt flow rate, while the degree of crystallinity improved compared with polyethylene/poly lactic acid. The degradation rate of composite film in the medium-term was faster than the previous-term, and the extent of degradation in solutions at different PH is: PH=9> PH=4> PH=7.We modificate polyethylene/poly lactic acid and polyethylene/starch to enhance their compatibility, increasing the content of blow moulding film degradable material from10to30copies by adding polyethylene-maleic anhydride to the composite materials. The mechanical properties decreased rapidly accompany with the increasing of the content of the degradable material, the degradation performance were apparent while the mechanical properties significantly decreased after degradation.