Investigation of Electrical and Mechanical Properties of PLA/Exuviae Biocomposites for High-Voltage Insulation

Abstract

This paper discusses the development of a new biocomposite made of polylactic acid (PLA) reinforced with black soldier fly (BSF) exuviae to improve the electrical insulation performance of high-voltage (HV) applications. Fourier transform infrared (FTIR) analysis was carried out to establish the type of chemical interaction between the PLA and the BSF exuviae. The electrical behaviour of the composite was measured in terms ofdirect current (DC) breakdown voltage, and mechanical strength was measured in terms of tensile strength. FTIR analysis confirmed the successful loading of exuviae into the PLA matrix, and new absorption bands were observed at amide I and II vibrations and the lipid C=O stretching, which is indicative of a high level of chemical interactions. Electrical testing showed that DC breakdown strength decreased greatly with exuviae content, especially at high filler loadings, and this was attributed to the effects of agglomeration. Mechanical testing revealed a distinct reduction in tensile strength and Young’s modulus with increasing exuviae content from 0% to 3%, which means the exuviae content reduced the load-bearing capacity with increased filler content. The results are useful in understanding the electro-mechanical behaviour of PLA/BSF exuviae composites and their potential and drawbacks as a sustainable material to be used in HV insulation.