表面改性和混杂对超高分子量聚乙烯纤维/环氧树脂复合材料性能的影响

Ultra high molecular weight polyethylene (UHMWPE) fibers possess outstanding properties such as high tensile strength and low density. However, their low surface polarity and poor heat resistance restrict the application of UHMWPE fibers as a reinforcing material for high performance composites. These shortcomings of UHMWPE fibers can be overcome by ultraviolet (UV) assisted grafting treatment and hybridization with aramid fibers. Results show that UHMWPE fibers could firstly be modified by means of an UV radiation assisted one step grafting process with acetone as solvent and acrylic acid as monomers, then the mechanical properties of composites of epoxy resin with the modified UHMWPE fibers was greatly enhanced; with the increasing monomer content in the acetone solvent, the tensile strength of UHMWPE fibers/epoxy resin composites increased obviously, while there was no significant change of flexural strength and impact strength. In order to further improve the heat resistance of UHMWPE fibers/epoxy resin composites, UHMWPE fibers were hybridized with aramid fibers and then the hybrid fibers were used as reinforcing material to produce hybrid fibers/epoxy resin composites. As a result, the deformation of the hybrid fibers/epoxy resin composites decreased by 66.7% at 90 compared to that of UHMWPE fibers/epoxy resin composites. The result proves that the pre-hybridization of UHMWPE fibers is an effective means to enhance the heat resistance of UHMWPE fibers/epoxy resin composites.