Effect of fiber surface treatment on mechanical properties of polyethylene / epoxy composites

Tensile and pipe performance tests were carried out on polyethylene/epoxy materials in which the polyethylene fibers were pre-treated to remove the binder and/or sized. The tensile modulus of the composites was increased by pre-treatment, although the tensile strength was almost the same. The knee point stress of the untreated composites decreased on sizing. The strength retention of pre-treated composites was higher than that of composites with both a binder and a size. This difference in pipe performance was caused by the different interphase resulting from pre-treatment and/or sizing.