Effect of PHBV-g-MA compatibilizer on the properties of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/polylactide blend/Diss fibers biocomposites

Abstract

This study investigates the morphology and properties of biocomposites based on a blend of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and poly (lactic acid) (PLA) 50/50 (w/w) reinforced with untreated (UNDF) and alkali-treated (ATDF) Diss (Ampelodesmos mauritanicus) fibers at 20 wt. %. Moreover, PHBV-g-MA used as the compatibilizer was added at 5 wt. % to the alkali-treated biocomposites. Morphology, and crystallinity, thermal, thermo-mechanical, rheological and mechanical properties of PHBV/PLA biocomposites were studied. The study showed that the treated Diss fibers were uniformly dispersed in both PLA and PHBV phases. This results in a good interfacial adhesion between the components, as observed by scanning electron microscopy (SEM). Further, the results also indicated that the compatibilized biocomposite samples showed an enhancement in crystallinity degree and heat deflection temperature (HDT) passing from 48.7% to 62.4% and 119.2 to 132.9°C, respectively, in comparison with the neat blend. Similar trend is also observed with the tensile data indicating a significant increase in Young's modulus by almost 48.5% compared to PHBV/PLA matrix. This is due to better interactions between Diss fibers and PHBV/PLA matrix. The results suggest the occurrence of a synergistic effect between PHBV-g-MA and alkali-treated Diss fibers in the development of materials with interesting properties and could be a potential means to expand their applications.