Adhesion of epoxy/glass fibre composites influenced by aging effects on sizings

This work systematically analyses the aging effects on sized glass fibres. The interfacial bond strengths in epoxy resin composites can vary depending on the kind of sizing formulation, properties and parameters of aging conditioning. A special focus is on qualification and further development of suited interface sensitive methods for characterisation of aging effects, enabling a prediction of deterioration caused by aging. Zeta potential, IGC, AFM, and wetting techniques reveal characteristic parameters of differently aged glass fibre surfaces and enable to predict the tendency of interfacial adhesion. Interface characterisation using pull-out and cyclic loading tests reflects aging effects on fibre surfaces very sensitively and is in a good agreement with surface characterisation results. (C) 2004 Elsevier Ltd. All rights reserved.