Technological watch

This research explores the influence of silane coupling on composites comprising recycled PET bottle waste foam and areca fruit fibre reinforced modified vinyl ester by comparing with untreated composite specimens. The hand layup method was adopted for fabrication and characterizations are done as per ASTM standards. The study investigates the effects of thermal and water-accelerated aging by subjecting the composites to sea and rainwater exposure, as well as elevated temperatures at 50 °C and 70 °C. Silane-treated and untreated specimens were comprehensively characterized. The findings indicate that silane-treated composites consistently outperform untreated counterparts in mechanical properties, even under accelerated aging. Despite a reduction in mechanical properties after prolonged exposure to 70 °C for 20 days, silane-treated composites exhibited robust laminar adhesion without significant delamination. Sea water aging resulted in inferior properties compared to rainwater aging, and silane-treated composites demonstrated slower flame propagation speeds in flame retardancy testing. In thermally aged composites, A51 and A52 series exhibited higher flame propagation speeds, while A21 and A22 series showed reduced speeds. Thermal conductivity measurements revealed increased values for aged composites, with composite A22 displaying the highest thermal conductivity of 0.179 W/mK. Overall, silane surface treatment significantly enhanced the stability of laminates against water and temperature aging. The resulting composites, with heightened strength and retained lightweight characteristics, show promise for applications in structural, automotive, defense, sports, and aviation industries.