In this paper, we investigated the effect of fiber content, interfacial compatibilization, and manufacturing
process on the mechanical properties (tensile, impact and creep) of sisal fiber (SF) reinforced high-density
polyethylene (HDPE) composites. The increase of fiber content and interfacial compatibilization with
maleic anhydride grafted HDPE (MAPE) were found to improve the mechanical properties of the composites. Compared with simultaneous blending, a pre-impregnation process with the compatibilizer, namely
MAPE, improved the interfacial bonding between the fibers and the matrix, which in turn improved the
mechanical properties of the composites. The General Power-Law equation was used to model the creep
behavior of the composites. The identified material parameters based on the creep data were used to predict the creep-recovery behavior of the composites, and good agreement was achieved between the predicted and experimental creep-recovery responses.