STUDY OF THE COMPATIBILIZATION OF POLYMER BLENDS OF PLA-PP

Abstract

Purpose: The interest in sustainability has increased the demand for materials from renewable sources or that are potentially reusable; recyclable or biodegradable. In order to make possible the application of these materials, the technical and scientific knowledge are applied in the development of blends with biodegradable constituents. In this study, polymer blends of poly(lactic acid) and polypropylene were prepared by twin screw extruder. Methods: The addition of polypropylene-graft-maleic anhydride (PP-g-MAH) or ethylene/methyl acrylate/glycidyl methacrylate (EMA-GMA) terpolymer as compatibilizer was studied. The polymer blends were comprised of PLA:PP ratios 70:30 with addition of 3 wt% of compatibilizer. The samples were processed by injection molding process and the products were subjected to thermal, mechanical properties and morphology analysis with a scanning electron microscope (SEM), thermal analyses (TGA/DSC) and X-ray diffraction (XRD). Results: The thermal analyses confirmed that addition of the compatibilizer has effect on crystalline melting temperature of the polymer components as well as on the mechanical properties. The SEM results showed the textural characteristics and the particles size of the polymers were modified after the synthesis of blends. The XRD results and TGA/DSC showed that the composites preserved the crystallization of polymers. The tensile strength of polymer blends increased with the presence of the compatibilizers and the morphology study of the polymer blends confirmed the better compatibily of PLA and PP by assistance of PP-g-MAH or EMA-GMA. Conclusion : The research results confirmed the application of polymer blend system to injection molding process.