Preparation and characterization of polypropylene/polylactide blends and nanocomposites and their biodegradation study

Melt blending technique was used for the preparation of blends of two different polymers (polypropylene (PP) and polylactide (PLA)) with/without compatibilizer and nanoclay. The effect of nanoclay on the properties of blends and PP was investigated. Compression molding was used for the preparation of films. PP/PLA (85/15) and PP/PLA/maleic anhydride (85/15/4) were chosen as optimum blends from tensile strength test for further characterization. Tensile strength of PP/PLA (85/15) blend improved with the addition of 4 phr resin compatibilizer. The content of nanoclay was varied from 0 wt% to 5 wt% in PP. The optimized blends were characterized by Fourier transform infrared (FTIR), differential scanning calorimetry, rheological studies, X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, biodegradability test, and ecotoxicology. FTIR studies indicated the presence of PLA and nanoclay in the PP matrix. The addition of compatibilizer increased the compatibility between PP and PLA. Biodegradability studies confirmed the biodegradable nature of the blends and composites. Nontoxic nature of biodegraded intermediates has been confirmed by the ecotoxicological tests.