Interfacial studies on surface modified Kevlar fibre epoxy matrix composites

Kevlar fibre/epoxy composites with superior interfacial strength were devel oped, by chemical treatment of the fibre surface with organic solvents. Mul tiple fibre pullout tests revealed that it is possible to raise the interfa cial strength to 63 MPa from a value of 39 MPa normally exhibited by untrea ted Kevlar fibre/epoxy composites. A physicochemical and morphological char acterization of the chemically treated fibre surface by microscopic and spe ctroscopic techniques, aids in the understanding of the observed interfacia l properties. The importance of surface oxygen content in matrix bonding an d mechanical interlocking of the fibre and matrix was established. Failure analysis of the pullout specimens reveals a strong correlation between the fracture features and the observed test data. (C) 1999 Elsevier Science Ltd . All rights reserved.