Production of Composite Plastics from Thermoplastic Tapioca-Casava Bagasse and Compatibilized Polyethylene Blends

Abstract

One of alternative solution for plastic disposal problem is by developing biodegradable plastic. The typical drawbacks of starch-based plastic is inferior of its physico-mechanical properties. In order to improve the physico-mechanical properties and compatibility of blending system, tapioca-casava bagasse was modified into thermoplastic tapioca-casava bagasse blends while polyethylene was compatibilized by addition maleic anhydride. The aim of this research was to produce composite plastic from thermoplastic tapioca-casava bagasse blends and compatibilized polyethylene (compt-HDPE, compt-LDPE and compt-LLDPE). This research investigated the effect of fiber content in formulating the tapioca-casava bagasse blends, as 5, 10, 15 and 20%; glycerol (as plasticizer) concentration, as 30, 35 and 40% to the mechanical, thermal, biodegradability and surface morphological properties of composite plastics. The result showed that fiber contents in blends tapioca-casava bagasse up to 15% can improve physico-mechanical properties (tensile stress at yield, tensile stress at break and thermal properties) but addition of glycerol more than 30% can decrease mechanical composite plastic properties especially for HDPE. Introduction of thermoplastic tapioca-casava bagasse in polyethylene composite plastic generally can decrease physico-mechanical properties plastic. Synthetic polymer that suitable with thermoplastic blends tapioca-casava bagasse was compt-HDPE. The best result gained from 40% thermoplastic blends with HDPE, 15% of fiber and 30% of glycerol contents. Biodegradability test showed that composite plastic can be degraded, but only natural component such as starch and fiber was degraded.