Development of polylactic acid‐untreated bamboo filler composite and its chemical and mechanical properties

Abstract

AbstractA fully bio‐based plastic composite comprising a polylactic acid (PLA) matrix with untreated bamboo filler (BF) was manufactured by a simple method. PLA and crushed bamboo flakes were compounded in a kneader and then injection molded without pretreatment of BF. The composites containing PLA and BF at 50:50 (PLA50/BF50) and 60:40 mass ratios (PLA60/BF40) were obtained. The PLA60/BF40 and PLA50/BF50 products were evaluated by thermal analysis (TG/DTA, DSC, and DMA), Fourier transform infrared (FTIR) spectroscopy analysis, and abrasive wear test. From the results, the composite of PLA and untreated BF was fabricated under high temperature and high‐pressure conditions, in kneading at 180°C and injection molding at 150–175°C and 95 MPa for 1.5 s. FTIR analysis indicated that changes in the functional groups of the composite products were dependent on the proportion of BF. Unfortunately, the BF did not improve the stiffness, viscoelasticity, and wear resistance of the PLA. However, the PLA50/BF50 product had a storage modulus comparable to that of the pure PLA product, and of which a 30% cost reduction was achieved by using abundant bamboo and reducing the amount of PLA.