THE ROLE OF INTERFACE AND FIBER ANISOTROPY IN CONTROLLING THE PERFORMANCE OF POLYETHYLENE-FIBER-REINFORCED COMPOSITES

The influence of the interface and fibre anisotropy on the performance of high-performance polyethylene (HP-PE)/epoxy composites was investigated. It was concluded that the relatively low experimentally found maximum values for shear and transverse strength of HP-PE/epoxy composites, incorporating surface treated fibres, are caused by a change in failure mode from debonding to fibre splitting with increasing levels of adhesion. To obtain more quantitative information about the role of fibre anisotropy on the strength of HP-PE composites, a micromechanical analysis was utilized to predict ultimate composite properties. Theoretical values for composite strength as obtained via micromechanics, assuming perfect adhesion, are in good agreement with experimental data for HP-PE composites incorporating plasma treated fibres, indicating that the highly anisotropic character of HP-PE fibres plays a predominant role in the structural performance of composites based on these fibres.