Effect of UV-Irradiation and Ozone Exposure on Thermal and Mechanical Properties of PLA/LDPE Films

Abstract

The mechanical properties of polymer composites based on polylactide vary significantly over a wide range of values. It has been established that photodegradation of lowdensity polyethylene – polylactide blends occurs both in the amorphous and in the crystalline phase of the PLA matrix, which leads to deterioration of the mechanical properties of the studied mixtures. Ozonolysis affects the strength parameters of polylactide-polyethylene samples as well as photodegradation. By the differential scanning calorimetry it is determined that the melting point of polylactide decreases by 2-4 °C, the glass transition temperature-by 1-3 °C, while the degree of crystallinity increases by 3-6%. In the process of ozonolysis, the thermophysical characteristics of PLA/LDPE have changed.