Impact of Thermal Cycling on the Performance of Glass, Basalt, and Carbon Fiber-Reinforced Bio-Based Resin Composites

Abstract Bio-based resins have demonstrated to be a technically viable solution to reduce crude-oil dependency in fiber-reinforced polymer (FRP) composites. However, their long-term performance, particularly their durability under harsh conditions, is still mostly unknown. The study presented in this paper investigates the performance of three types of FRP composites, with different fibers and thermoset bio-based resins, under thermal cycling. E-glass, basalt, and carbon fiber composites, produced by vacuum infusion with respectively two compositions of bio-based unsaturated polyester resin (developed in-house) and a bio-based epoxy resin, were considered in this study. In parallel, conventional, fully oil-based counterparts incorporating similar fibers and layups have also been considered as benchmark. The composites were exposed to 100, 200, and 300 thermal cycles, each cycle comprising a segment at –20°C (5 h), a segment at 50°C (5 h), and 2 h of heating and cooling in between temperature plateaus (total cycle duration of 12 h). Mechanical (tension, compression, in-plane shear, and interlaminar shear) and thermomechanical (dynamic mechanical analysis) testing of the composites was performed after each set of cycles. The results of those tests show that the performance of the bio-composites is comparable to their oil-based counterparts. Thermal cycling produced low to moderate effects in the polymer composites, with property reductions ranging between 5% and 30% in more extreme cases. The results were compared to those available in the literature regarding thermal cycling durability of conventional FRP composites, demonstrating a good agreement with data from previous studies.