WATER ABSORPTION BEHAVIOR OF POLYPROPYLENE–CHITOSAN COMPOSITES ENHANCED WITH CARBON FILLERS FOR FUEL CELL USE

This study examines the water absorption characteristics of polypropylene-chitosan composites modified with conductive fillers to assess their potential for fuel cell applications, where both conductivity and moisture resistance are critical. Nine composite samples were prepared: a control sample (AX) containing only polypropylene and chitosan nanoparticles, and eight experimental samples divided into two groups with varying concentrations (5-20%) of either activated carbon (B1-B4) or graphene (C1-C4) as conductive fillers. Water absorption was measured over seven days to evaluate how each filler type and concentration impacted moisture uptake. Results showed that the control sample exhibited the lowest water absorption, underscoring the inherent moisture resistance of the polypropylene-chitosan matrix. However, the absence of conductive fillers in AX limits its potential for fuel cell applications. Among the activated carbon-enhanced samples, Sample B2 (10% activated carbon) demonstrated the most favorable balance of moderate water absorption and potential conductivity. In the graphene group, Sample C2 (10% graphene) displayed a similar balance, with stable moisture resistance and likely enhanced electrical conductivity due to graphene’s properties. Higher filler concentrations in both groups increased water absorption, suggesting that excessive filler can introduce porosity, thereby reducing material stability. The findings indicate that composites containing 10% conductive filler—either activated carbon or graphene—are optimal, combining moisture resistance with expected conductivity. These materials show promise for further testing in fuel cell environments, where their properties could support both durability and performance