Effect of aerosil and talc reinforcements on the tensile properties of natural damar resin matrix

Abstract This study investigates the effect of particulate reinforcements, specifically aerosil and talc, on the tensile properties of composites based on a natural damar resin matrix. Damar resin was selected for its renewable nature and wide availability; however, its inherent brittleness limits its use as a matrix material. To address this limitation, optimization was performed by blending damar resin with polyester resin in three ratios (1:1, 2:3, and 2:1). The optimal formulation was 2:1 (polyester:damar), which was subsequently used as the base matrix for tensile test specimens. Three specimen groups were prepared: specimen A (polyester : damar = 2:1), specimen B (specimen A with 5 g aerosil and 45 g talc), and specimen C (specimen A with 90 g talc). Each group consisted of three replicates. Tensile testing, conducted in accordance with ASTM D638, was performed to determine tensile strength and elastic modulus. The results demonstrated that the addition of reinforcing particles markedly enhanced the mechanical performance of the composites. Specimen B exhibited the highest tensile strength (11.83 MPa), while specimen C achieved the highest elastic modulus (3314.13 MPa). In contrast, specimen A showed the lowest values due to the absence of reinforcement. Overall, the combination of aerosil and talc was found to be effective in improving both strength and stiffness, with specimen B representing the most promising formulation for sustainable composite applications.