Development of Renewable Resource-Based Cellulose Acetate Bioplastic: Effect of Process Engineering on the Performance of Cellulosic Plastics

摘要

This paper deals with the development of a cellulose acetate biopolymer. Plasticization of this biopolymer under varying processing conditions to make it a suitable matrix polymer for bio-composite aplications was studied. In particular, cellulose acetage was plasticized with varying concentrations of an eco-friendly triethyl citrate (TEC) lastgicizer, unlike a conventional, petroleum-derived phthalate plasticizer. Three types of processing were used to fabricate plasticized cellulose acetate parts: compression molding, extrusion followed by compression molding, and extrusion followed by injection molding. The processing mode affected the physico-mechanical and thermal properties of the cellulosic plastic. Compression molded samples exhibited the highest impact strength, tending towards the impact strength of a thermoplastic olefin (TPO), while sampels that wee extruded and then injection moded exhibited the highest tensile strength and modulus values. Increasing the plsticizer content in the cellulosic plastic formulation improved the impact strength and strain to failure while decreasing the tensile strength and modulus values. The coefficient of thermal expansion (CTE) of the cellulose acetate increased with increasing amounts of plasticizer. Plasticized cellulose acetate was found to be processable at 170-180 deg C, approximately 50 deg C below the melting point of neat cellulose acetate.