Mechanical behavior of palm oil–based composite foam and its sandwich structure with a flax–epoxy composite

Abstract

ABSTRACT Empty fruit bunch fiber (EFB), an abundant biomass waste from the palm oil industry, is used to reinforce palm oil–based polyurethane foam (POPU), and the mechanical properties of the composite foams are also assessed. The fiber–foam interfacial adhesion is also investigated by SEM images and Fourier transform infrared spectrometry. The results show that the composite foam reinforced by 15–30% EFB volume fractions could be enhanced by up to 10 times in flexural strength and twice in compressive strength compared to neat POPU. The composite foams with 20% and 30% volume fraction of EFB are exploited as a core in a sandwich construction with unidirectional flax fiber–reinforced epoxy composites (as face sheets). Sandwiches using EFB/POPU composite foam cores exhibited better toughness and achieved higher flexural energy at break compared to that using a commercial poly(ethylene terephthalate (PET) foam core. Furthermore, the failure mechanisms occurred under a combination of flexural and shear deformation. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133 , 43977.