Mechanical and thermal properties of environment-friendly "green" composites made from pineapple leaf fibers and poly(hydroxybutyrate-co-valerate) resin

This paper presents the mechanical and thermal properties of unidirectional , degradable, environment-friendly "green" composites made from pineapple f ibers and poly(hydroxybutyrate-co-valerate) (PHBV) resin. Tensile and flexu ral properties of the "green" composites with different fiber contents were measured in both longitudinal and transverse directions. Compared to those of virgin resin, the tensile and flexural strengths of "green" composites are significantly higher in the longitudinal direction while they are lower in the transverse direction. However, the mechanical properties are lower than those predicted by simple models. Scanning electron microscope (SEM) p hotomicrographs of the tensile fracture surfaces demonstrate fibers being p ulled out from the matrix, the interfacial failure, fiber fibrillation, and the nonunidirectional nature of the "green" composites. The thermal behavi or of the "green" composites, studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), showed that the presence of pin eapple fibers does not affect the nonisothermal crystallization kinetics, c rystallinity, and thermal decomposition of PHBV resin.