Effect of Soybean Oil in Eggshell Powder Filled Polylactic Acid Composites on its Mechanical, Thermal and Rheological Properties

This research aims to study the mechanical, thermal and rheological of eggshell powder (ESP) filled polylactic acid (PLA) with and without adding soybean oil (SBO). The ESP filled in PLA at 10%wt were compounded by using an internal machine at 190°C. SBO was filled with various contents between 0-10 %wt in PLA-ESP composites. Morphological, mechanical, rheological and thermal properties were investigated on the sample obtained by an injection molding. The result indicated that the ultimate tensile strength and strain decreased with SBO in PLA-ESP composites. However, the strain has increased obviously up when adding SBO. This was due to the presence of microvoids that was confirmed by scanning electron microscope. Furthermore, SBO played an important role reduce between polymer-polymer interaction and ESP particles. Melt flow index of PLA-ESP composites with and without SBO exhibited higher than neat PLA. Adding SBO into PLA-ESP composites reduced onset temperature degradation (Tonset) and maximum temperature degradation (Tmax) while ESP increased of char residue content.