Preparation and Characterization of Poly(L-lactic acid)/Chitosan/Microcrystalline Cellulose Blends

To prepare biodegradable and biocompatible polymer composites with better thermal and mechanical properties, five different Poly(L-lactic acid)(PLLA)/Chitosan/ Microcrystalline Cellulose (MCC) blends, with a different ratio, were prepared and characterized. MCC was extracted from jute fiber by conventional acid hydrolysis method with 64 wt% H2SO4 and chitosan was extracted from shrimp shell by successively carrying out demineralization, decolorization, deproteinization and deacetylation steps. PLLA was blended with a constant percentage (20 percent) of chitosan and a calculated amount of MCC by solution casting method using a suitable solvent for each. Prepared samples were characterized by Fourier-Transform Infrared Spectroscopy (FTIR) for the identification of their compatibility in blends, Wide-Angle X-ray Diffraction (WAXD) for crystalline species and crystallinity analysis, Thermo-Gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA) for thermal properties measurement. Results from FTIR analysis showed that except hydrogen bonding, there are no new characteristic absorption peaks observed in the spectrum of blends and confirm that PLLA, Chitosan, and MCC have better compatibility in blends via intermolecular hydrogen bonding. WAXD profiles data show the variation in crystallinity of different blends. TGA and DTG results indicate that MCC can improve the heat resistivity of the PLLA/Chitosan/MCC blends by the addition up to 5%.