Thermoplastic cassava starch/poly(lactic acid) blend reinforced with coir fibres

One way to obtain more benefit from coconut waste is to utilise coir fibre (CF) as reinforcement in biodegradable plastics. The current work aims to study the effect of CF on the performance of a thermoplastic starch (TPS)/poly (lactic add) (PLA) blend. TPS/PLA/CF biocomposites with a constant TPS: PLA ratio of 60:40 by weight and various concentrations of CF (2.7, 55, 82, and 10.9 wt%) were fabricated using a twin-screw extruder and then injection moulded into dumbbell-shaped specimens for property testing. The obtained TPS/PLA/CF biocomposites exhibited improved stiffness and hardness, corresponding to the stronger hydrogen bond interaction between starch and PLA and/or starch and CF and the increased PLA crystallinity. Due to the reinforcing effect, the biocomposites also exhibited lower extensibility, tensile strength and impact strength compared to the TPS/PIA blend. Incorporating CF enhanced compatibility between the TPS and PLA phases; however, it also caused reduced melt flow ability, increased shear viscosity, and a decreased shear thinning effect of the blend. The resulting TPS/PLA/CF biocomposites could potentially be used to produce bio-based and biodegradable injection-moulded products. (C) 2020 Elsevier B.V. All rights reserved.