Process design of bamboo carbon reinforced polylactic acid composites via twin-screw extrusion

Bamboo carbon (BC) reinforced polylactic acid (PLA) composites play a significant role in optimizing the utilization of bamboo resources and advancing green, low-carbon, and circular development. To minimize production costs, a relatively high content of bamboo carbon (40 wt.%) was incorporated into the PLA matrix. However, for the high content of BC filler, the optimal process of balancing filler amount and interfacial properties is still unknown. In this study, a three-factor, four-level orthogonal experimental design was employed to investigate the effects of various processing parameters, initiated with twin-screw extrusion, on the crystalline structure, thermal properties, and mechanical performance of the composites. The optimal processing conditions for BC/PLA composites were determined to be a processing temperature of 195 °C, a screw speed of 120 rpm, and a feed rate of 15 g/min. Under these conditions, the tensile strength of the resulting composite reached 40.9 MPa. This study provides valuable insights for enhancing the performance of BC/PLA composites while promoting their large-scale application in sustainable materials engineering.