Effect of process variable on the mechanical and thermal behavior of a polypropylene composite reinforced with short bamboo fibers by hot compression

This study investigates the effect of fiber content and coupling agent concentration on the mechanical and thermal behavior of a polypropylene-based composite. The materials were fabricated via hot compression molding using pellets composed of polypropylene (PP) modified with maleic anhydride-grafted polypropylene (MAPP) and reinforced with short bamboo fibers derived from Guadua angustifolia Kunth (GAK). The fibers were previously extracted through the steam explosion technique. The research was carried out in two stages: first, the composite materials were produced; second, their mechanical and thermal properties were comprehensively characterized. The incorporation of GAK fibers and MAPP significantly altered the mechanical performance of the PP matrix, yielding stiffer composites with improved flexural strength and impact resistance. The optimal formulation, containing 50 wt% GAK fibers and 4 wt% MAPP, resulted in a 322% increase in elastic modulus (2.9 GPa) compared to neat polypropylene (0.7 GPa). Both variables, fiber content and compatibilizer concentration, were found to exert a substantial influence on the mechanical behavior of the resulting composites.