Biocomposite consisting of miscanthus fiber and biodegradable binary blend matrix: compatibilization and performance evaluation

Abstract

Biocomposites were fabricated from miscanthus fibers and a blend composed of poly(butylene succinate) (PBS)/poly(butylene adipate-co-terephthalate) (PBAT) matrix by extrusion and injection molding. Due to the reinforcing effect of miscanthus fibers, the tensile, flexural, and storage modulus of the composites were increased with increasing fiber content from 30 to 50 wt%. Young's modulus of the composite was evaluated by parallel, series, Hirsch and Halpin-Tsai models. It was found that the Hirsch model has good agreement with the experimental modulus of the composites. There was a sharp reduction in tensile strength and impact strength after the incorporation of miscanthus fibers into PBS/PBAT blend matrix. These reductions were due to the incompatibility between the fibers and the matrix. Therefore, maleic anhydride (MAH) functionalized PBS/PBAT blend was prepared and used as compatibilizer to improve the compatibility between the fibers and the matrix. The composites prepared with 5 wt% MAH functionalized compatibilizer showed significant improvement in mechanical properties compared to their uncompatibilized counterparts. The morphological analysis of the composites displayed good fiber-matrix interaction in the presence of compatibilizer whereas composites showed poor interface between the phases without compatibilizer. The shear thinning behavior of the composites was increased compared to neat PBS/PBAT blend. The increased shear thinning behavior of the composite was attributed to the reduced polymer chain entanglement in the presence of fibers. The miscanthus fibers reinforced PBS/PBAT composites can offer significant benefit in terms of economic competitiveness and functional performances.

Biodegradable biocomposites from poly(butylene adipate‐co‐terephthalate) and miscanthus: Preparation, compatibilization, and performance evaluation

“…The MAH‐ g ‐PBAT and PBAT/miscanthus composites did not show significant difference in the melting and glass transition temperature. In our previous study, we have found similar observation in the PBS/miscanthus composites . The crystallization temperature of the PBAT is around 80 °C [Figure (B)].…”

“…The storage modulus of the PBAT is 2 GPa at −45 °C whereas the PBAT/miscanthus fiber composites have storage modulus of 2.75 GPa at −45 °C (Figure ). There was a sharp reduction is storage modulus of the PBAT and its composites at −20 °C because of the molecular chain mobility increased at glass transition temperature . The PBAT/miscanthus composites showed significantly higher storage modulus than neat PBAT up to 100 °C.…”

“…This suggests that the affinity between the matrix and fibers is poor . The observed insufficient compatibility between the components was responsible for the observed reduced tensile and impact strength of the uncompatibilized composites . In contrast, the compatibilized composites morphology [Figure (B,D)] showed better interface/adhesion while the fibers were well embedded with the matrix.…”

Biodegradable compatibilized polymer blends for packaging applications: A literature review

“…PBAT is synthesized from 1,4‐butanediol, terephthalic acid, and adipic acid monomers by polycondensation reactions . PBAT demonstrates good flexibility with a melting and glass transition temperature of 120 and −17 °C, respectively .…”

Carbon Dioxide–Derived Poly(propylene carbonate) as a Matrix for Composites and Nanocomposites: Performances and Applications

“…The elongation at the break of PPC was drastically reduced with 10 wt% HPF and plateaued with a further increase in HPF content up to 40 wt%. This phenomenon is a typical characteristic of short fiber reinforced composites . In another study, biocomposites were prepared from PPC polymer with Caulis Spatholobi residue fiber (CSRF).…”