Biocomposites of Alfa fibers dispersed in the Mater-Bi® type bioplastic: Morphology, mechanical and thermal properties

This paper focuses on the analysis of thermal and mechanical properties of novel biocomposites of Alfa fibers dispersed in a bioplastic of the Mater-Bi® type in relation with their morphology. These biocomposites obtained by twin screw extrusion were injection molded. Mater-Bi® is a commercial biodegradable thermoplastic based on poly(butylene terephthalate-co-butylene adipate) and starch. Raw and alkali treated Alfa fibers were used as reinforcement. Thermal analysis showed significant increase of the crystallization rate with the incorporation of Alfa fibers and enhancement of thermal stability by alkali treatment. Modulus and tensile strength of biocomposites also increased whereas toughness and elongation at break decreased upon increasing the fibers fraction. Scanning electron microscopy (SEM) on fractured surfaces indicated good adhesion between the matrix and the treated or untreated Alfa fibers.