Effect of pectin biopolymer addition on the mechanical, dynamic, and water absorption behavior of natural fiber-reinforced epoxy composites

The demand for sustainable, high-performance composites has created a need for
natural fiber–reinforced systems with improved mechanical, durability, and environmental resistance properties. This study addresses this gap by developing epoxybased composites reinforced with 30 vol% areca nut fiber and varying pectin filler
contents from Passiflora edulis husks, with both reinforcements silane-treated to
enhance fiber–matrix adhesion. Mechanical tests showed that the optimum formulation achieved~ 28% higher tensile strength, ~24% higher flexural strength, and
improved impact energy compared to the unfilled fiber composite. Fatigue life exceeded 27,000 cycles at 25% and 50% UTS, indicating strong cyclic load tolerance.
Higher filler content enhanced hardness and creep resistance but resulted in a~35%
increase in water absorption. SEM analysis confirmed uniform filler dispersion and
minimal interfacial gaps, correlating with the mechanical improvements. These results demonstrate that targeted filler loading can balance strength, durability, and
moisture resistance, making the composites promising for demanding industrial
applications.