Study Of Modified Kevlar Fiber And Kevlar Fiberand Epoxy Matrix Of Kevlar Fiber Filament Wound Composites

Kevlar fiber composites have been widely used in aerospace,military affairs, mechanism and so on, But Kevlar fiber has a poorintereaction with matrix because of the skin-core structure, which badlyweaken the performance of Kevlar fiber in composites, the keys to solvethis problem are the surface treatment of Kevlar fiber and thedevelopment of high performance resin marched with Kevlar fiber well.In this work, The Kevlar fibers were treated by phosphorousacid(PA) solutions of different concentrations. The surface properties ofthe treated Kevlar fiber and the interfacial properties of the fiber/epoxyresin composites were investigated. On the basic of the treatment ofKevlar fiber with PA solution, the effects of structure and property ofresin matrix on Kevlar composite were studied. The results show that theamount of the oxygenous functional groups on the surface reachedmaximum after being treated with 20% PA solution. The amount of the oxygenous functional groups and the surface roughness decrease asthe concentration of PA solution increases. After being treated with 20%PA solution, the interlaminar shear strength(ILSS) of Kevlar fiber/epoxycomposites reached 62MPa and the interfacial shear strength(IFSS) ofKevlar fiber/epoxy composites increased by 18%.Meanwhile the mechanical property and thermal mechanicalproperty of epoxy/Kevlar fiber composite were analyzed. The resultsshow that there exist oxygenous functional-groups on the fiber surfaceafter being treated with phosphorous solution, which can provide goodcompatibility between Kevlar fiber and glyceride epoxy resins. For theKevlar fiber/optimized resin matrix composites, the percentagetranslation of fiber strength of NOL rings attain to 95%, the ILSS and theIFSS are 79MPa and 76MPa, respectively. Moreover, the interfacialproperties of composites are excellent. The amount of the functionalgroups on the fiber surface and the surface roughness are the curialfactors to improve interfacial properties of Kevlar fiber/epoxycomposites.