Hybrid composites based on polypropylene and carbon fiber and epoxy matrix

Polypropylene fiber and mercapto-modified polypropylene blend fiber (PPEVAS H) were combined with carbon fiber as reinforcing elements in so-called hyb rid epoxy composites. The impact performance and dynamic mechanical propert ies of these materials were investigated. Hybrid composites containing PPEV ASH blend fibers display higher impact strength than plain carbon fiber com posites but the performance is lower than plain PPEVASH-epoxy composite. Th e increasing of damping resistance and glass transition temperature, measur ed in terms of maximum damping temperature, of the hybrid EP/PPEVASH/CF com posite may be attributed to several factors and include the interfacial adh esion PPEVASH fiber-matrix and PPEVASH-carbon fiber layers and the increasi ng of the crosslinking degree of the matrix, promoted by the presence of me rcapto groups at the modified PP fiber surface. The presence of mercapto gr oups in the modified PP fiber also contributes for an improvement of the th ermal stability, measured by thermogravimetric analysis. (C) 2000 Elsevier Science Ltd. All rights reserved.