Ultra-high-modulus polyethylene fibre composites: I—The preparation and properties of conventional epoxy resin composites

It has been shown that conventional techniques can be used to prepare epoxy resin composites incorporating ultra-high-modulus polyethylene (UHMPE) fibres as the reinforcing phase, either as continuous filament yarn or woven fabric. These composites showed very satisfactory values of stiffness and strenght, and very good energy absorption in Charpy impact tests. The interlaminar shear strength of the composites could be significantly increased by plasma etching of the fibres in oxygen gas. This treatment reduced resin cracking in flexural and impact tests, but did not reduce the impact energy absorption very greatly because the latter is primarily associated with plastic deformation of the fibres. The composites were also subjected to preliminary environmental tests, with very encouraging results.