A Study on the Thermal Conductivity of Poly(lactic acid)/Alumina Composites: The Effect of the Filler Treatment.

The excessive utilization of petroleum-based products has given rise to environmental concerns that have led to the shift in the research interest toward recyclable and biodegradable products. Polylactic acid (PLA), an aliphatic polyester that can be obtained from renewable sources, is used in a wide range of applications in different industrial sectors. This study demonstrates the change in the thermal conductivity of 30% alumina filled PLA after a hydrophobic surface modification was applied to the filler. Fourier transmission infrared and X-ray photoelectric spectroscopy results confirmed the successful modification of the alumina particles surfaces. The improvement in the interaction between the modified alumina and PLA matrix was revealed by examining the morphology micrograph obtained by field emission scanning electron microscopy. Since alumina is a highly thermally conductive material, the enhancement in the interfacial adhesion between the filler and matrix leads to an increase of 120% in the thermal conductivity of the PLA/Alumina composite compared to that of the neat PLA. In addition, the PLA/Alumina composite showed an increase in the storage modulus due to the high stiffness of alumina.