Characterization of pultruded composites of vinyl ester and unsaturated polyester resins with different fiberglass reinforcements

Abstract

Different combinations of matrices and reinforcements in composites make the study of this class of materials a challenge, especially when pultrusion is the manufacturing process employed. Pultrusion is well documented in the literature and offers numerous applications across various sectors, including automotive, construction, aerospace, and furniture industries, among others. In this study, glass fiber-reinforced resin composites were produced via pultrusion, varying between unsaturated polyester (UP) and vinyl ester (VE) resins, and glass fibers in the forms of filaments, woven fabric (WF), and mat (MAT). The composites morphological properties (SEM), physical properties (density and void content), dynamic-mechanical properties (DMA), and mechanical properties (tensile and impact strength) were evaluated. Considering the properties assessed, composites with vinyl ester resin exhibited similar density, higher glass transition temperature, greater storage and loss moduli by DMA, improved matrix/reinforcement adhesion as observed by SEM, higher tensile and impact strengths, and lower void content compared to those with unsaturated polyester resin. Regarding the reinforcement type, the mat presented superior thermal, morphological, and impact resistance properties, whereas the woven fabric demonstrated lower void content and higher tensile strength than the mat. Ultimately, the best results among the produced composites were obtained with the VE/MAT and VE/WF samples.