LAUSR

Electrospun veils from copolyethersulfones (coPES) with a number-average molar mass (Mn) of 9000 g/mol (coPES9k) and 20,000 g/mol (coPES20k) were prepared as soluble interlaminar veils for carbon fiber/epoxy composites. Dry carbon fabrics were covered with electrospun veils and then infused with an unmodified epoxy resin to prepare reinforced laminates. CoPES powder was predissolved in the unmodified epoxy to obtain an epoxy/coPES blend used for preimpregnation of laminates which were compared to the laminates obtained with resin infusion. The thermoplastic content varied from 10wt% to 20wt% for coPES9k and from 5wt% to 10wt% for coPES20k. Unreinforced samples with no carbon fabrics were also studied. The coPES9k veils showed full solubility and homogeneous morphology when added to the epoxy resin. Unreinforced samples, modified by coPES9k veils, showed only minor morphological differences compared to epoxy/coPES blends obtained from coPES9k powder predissolution. The glass transition temperatures for these samples displayed differences less than 10°C. Carbon-reinforced samples obtained using the same route showed larger differences. The coPES20k veils showed undissolved fibers and inhomogeneous morphologies when blended with an epoxy in the unreinforced samples.