Interfacial shear strength in glass-fiber/vinylester-resin composites

This study is devoted to the determination of the interfacial shear strength in glass-fiber/vinylester-resin composites. Glass fibers and vinylester matrix surfaces are first studied by using a wettability technique in order to quantify the thermodynamic properties of the interface, i.e, the level of the fiber/matrix adhesion energy, and then to estimate the interfacial shear strength according to a recent model. The mechanical properties of the interface are therefore determined by means of a microdroplet pull-out test on model composites and measurements of interlaminar shear strength on unidirectional composites. Similar results are obtained in all cases, indicating that the thermodynamic approach is a good tool for the estimation of the interfacial shear strength in composite materials. (C) 1996 Elsevier Science Limited