Research On Carbon Fiber Reinforced Polyvinylidene Fluoride Composite

Carbon fiber reinforced composites are widely used in aeroplane,automotives,green energy and sports goods fields,due to the light weight and high strength.Because of the inert nature of carbon fiber,the interface between carbon fiber and PVDF(Polyvinylidene fluoride)is very weak and the reinforcing effect of carbon fiber is bad.In offshore oil and gas industry,there is an intense need for high strength and chemical resistant composite material,so the development of PVDF/CF composites is of vital importance.The main purpose of this study is to modify the PVDF/CF interface and improve the reinforcing effect of carbon fiber in composite.In this study,three methods were used to improve the interface bonding in PVDF/CF composite.Firstly,modify the carbon fiber with KH570 and fluorine silane coupling agent.Secondly,modify PVDF matrix with MAHg-PVDF compatilizer.Furthermore,the combination of carbon fiber surface modification and PVDF matrix modification was studied.Thirdly,use recycled carbon fiber oxidized by air to reinforce PVDF.For these three PVDF/CF composite systems,the surface morphology,elements and functional groups change of modified carbon fiber were studied.The fracture morphology,interfacial shear strength and wettability of the improved interface were studied.And the flexural properties,impact properties and dynamic mechanical properties of composite were also studied,which proved the better mechanical properties after modification.In addition,carbon fiber length distribution and average length of PVDF/CF composites were also studied.