Effect of Precipitated Calcium Carbonate on Physical, Mechanical and Thermal Properties of Cassava Starch Bioplastic Composites

Abstract

The development of bioplastic composites from various natural polymers reinforced with Precipitated Calcium Carbonate (PCC) has become a field of increasing interest. In this study, the effect of PCC on the physical, mechanical and thermal properties of a cassava starch matrix composite was examined. The bioplastic composites were made of cassava starch and mixed with glycerol as a plasticizer and 0-10% by weight of PCC. The material was then poured into a mold and oven dried. The physical, thermal and mechanical properties of bioplastic/PCC composites were investigated using Tensile Strength measurements, X-Ray Diffraction, Thermogravimetric Analysis, Scanning Electron Microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FTIR). The optimum tensile strength was obtained upon the addition of 4 % PCC. The addition of PCC improved the thermal stability of bioplastic/PCC composites. The results of X-ray Diffraction testing showed an increase in the crystallinity of the bioplastic/PCC composites with increase in PCC content but there is a decrease in the moisture absorption. SEM images indicated that the PCC filler content was incorporated into the matrix. In general, FTIR indicated the bioplastic/PCC composites were hydrophilic and the addition of PCC reduced the hydrophilic properties by damaging the hydrogen bonding between starch molecules and water.