Effect of Compatibilizer Content on the Mechanical Properties of Bioplastic Composites via Hot Melt Extrusion

Polyhydroxybutyrate fiber biocomposites were prepared via twin screw extrusion. Results show mechanical properties of short natural fiber composites can be greatly improved with the addition of a compatibilizer. Compatibilizer composites exhibited an increased resistance to water absorption at low temperatures. A considerable increase in flexural modulus was also observed, in particular for the jute fiber composites. The dispersion of fibers was visibly improved as was observed using optical microscopy which allowed for a more even transfer of stress throughout the composite matrix. Lyocell composites however continued to display fiber agglomerates and although these were visibly reduced as PHB-g-MA content increased.