Analisis Pengaruh Campuran Polyester Dan Vinylester Terhadap Sifat Mekanik Dan Sifat Fisik Pada Matrik Bahan Komposit

This study aims to determine the effect of blending polyester resin and vinyl ester resin on the mechanical and physical properties of a composite matrix. An experimental method was employed, with specimens fabricated using the casting technique. The resin composition variations tested were 100% polyester : 0% vinyl ester, 70% polyester : 30% vinyl ester, 50% polyester : 50% vinyl ester, and 30% polyester : 70% vinyl ester. Mechanical properties were evaluated using the Charpy impact test in accordance with ASTM D6110 standards, while physical properties were examined using a Scanning Electron Microscope (SEM). The results indicate that resin composition variations influence the impact value of the composite matrix. The highest average impact value (0.155 J/mm²) was obtained with the 30% polyester : 70% vinyl ester variation, whereas the lowest value (0.008 J/mm²) was observed with the 100% polyester : 0% vinyl ester variation. SEM observations revealed the presence of microcracks, voids, and uneven fracture surfaces. In conclusion, increasing the vinyl ester resin content enhances the composite matrix's toughness against impact loads. The 30% polyester : 70% vinyl ester variation represents the optimal composition, as it yielded the highest impact value.