Eco-friendly laminates for extreme environments: potential for application in high durability structures

Abstract

The durability of hybrid composites under environmental and biological stresses is a significant challenge for sustainable structural materials. This study assessed vacuum-infused hybrid composites made of Pinus elliottii veneers, unidirectional jute fabrics, fiberglass mats, and an unsaturated isophthalic polyester matrix. Manufactured via the Vacuum Infusion Process (VIP), composites with varied stacking sequences were tested against fungal decay and accelerated weathering. Decay tests using Trametes versicolor involved 16 weeks of incubation, monitoring mass loss weekly. Accelerated weathering in a QUV chamber exposed samples to cycles of UV radiation, simulated rain, and moisture for 15 weeks, with weekly evaluations including mass loss, colorimetric analysis (CIELab), and FTIR spectroscopy. Fiberglass-faced composites demonstrated superior T. versicolor resistance, with minimal mass loss due to protective polyester and fiberglass layers. Conversely, wood-faced composites were more vulnerable, showing greater mass loss and chromatic changes. Weathering caused significant reductions in chromatic parameters (a* and b*), especially in wood-faced composites, due to lignocellulosic degradation. FTIR analysis revealed carbonyl and ether bond breakdown in the polyester matrix, with more pronounced degradation in hydrophilic jute-layered composites. These results underscore the potential of hybrid composites as durable, sustainable materials for extreme environments, with tailored configurations enhancing resistance to environmental and biological stresses.