Talc filled polylactic-acid biobased polymer composites: tensile, thermal and morphological properties

Global warming due to human activities (i.e., burning fossil fuels) has led to many issues, such as extreme weather (storm or drought) and rise in sea level making low land uninhabitable. One of the solutions to mitigate the global warming is to promote the use of biobased material. In this work, various dosage of talc powder ranged from 5, 10, 30 and 40 wt% were added into polylactic acid (PLA) to form biobased polymer composites. The biobased polymer composite has the potential to replace fossil-based polymer for sustainable packaging application. The PLA/talc composites were prepared by using melt blending method and compressed into thin sheet for characterisation test. The effect of talc content on the thermal properties and tensile performance of the PLA composites were investigated. Scanning electron microscope was used to study the fracture surface of the composites and the dispersion of talc powder in the matrix. Results showed that the addition of talc ranged from 5 to 30 wt% can enhance the Young's modulus and thermal stability of the composites but there is no improvement in tensile strength and elongation at break due to poor interfacial adhesion. The addition of talc beyond 30 wt% (i.e., 40 wt%) did not show improvement in thermal stability because at high talc content, the formation of agglomerate and voids allows the oxygen to diffuse into the matrix which lead to decomposition process.