Comparative Mechanical Characterization of Recycled PVC and Wood–Plastic Composites

Abstract

Recycled polymers offer opportunities for circular material use, yet their mechanical performance is often limited by feedstock variability. This study provides a controlled comparison of neat recycled PVC and WPC (PVC + 20 wt.% wood flour) processed under identical extrusion and compression-molding conditions. Tensile, flexural and hardness tests were conducted according to ASTM standards, and results are reported as mean ± standard deviation (n = 5). The WPC exhibited modest but measurable increases in tensile strength (~12%), flexural strength (~8%), and Shore D hardness (~8.5%), while tensile and flexural moduli remained statistically comparable between the two materials. Flexural modulus exceeded tensile modulus for both materials, consistent with surface-dominated stress distributions in bending. The findings demonstrate that incorporating 20 wt.% wood flour into recycled PVC can enhance selected mechanical properties without compromising stiffness, offering a performance profile consistent with material-substitution pathways in circular-economy strategies. The study also highlights the influence of recycled feedstock variability and identifies the need for future microstructural characterization to confirm the hypothesized deformation and failure mechanisms.