Preparation And Characterization Of Chemically Modified Polyimide Fiber And Fep Composites

Single conventional materials often have shortcomings in mechanical properties and chemical properties.Composite materials can combine the strengths of several materials and complement each other to make the composites have more comprehensive performance.As the most widely used composite material,fiber reinforced resin composites are composed of reinforcing phase fibers and matrix phase resins.The properties of fibers and resins often determine the properties of the composite.As an emerging high-tech fiber,polyimide fiber has some excellent properties that traditional fiber does not have.FEP resin not only has the excellent properties of ordinary Fluor plastics,but also is easy to process,but its mechanical properties are poor.Therefore,enhancing the mechanical properties of the FEP resin by adding polyimide fibers to the FEP resin is of great significance for expanding the application of the FEP resin.Since the polyimide fiber is directly added to the FEP resin,the fiber tends to agglomerate in the resin during molding,which affects the uniformity and stability of the composite.Therefore,the research of this subject is to chemically modify the polyimide fiber to reduce the agglomeration of the fiber in the resin,and basically does not affect the strength of the fiber.In this paper,the fibers were chemically modified by two systems: ethylenediamine/perfluorooctanoic acid and polyethylene mine/perfluorooctanoic acid.The modified polyimide fiber was characterized by SEM,FTIR,XRD,TG,EDS,etc.It was proved that the modification of polyimide fiber was carried out according to the experimental plan,and the fiber was modified.The sexual process has a certain understanding,and discussed the advantages and disadvantages of the modified system,and determined the modified fiber used in the composite.Through the experiment,the molding parameters of the composite material were preliminarily determined,and the unmodified polyimide fiber and the fibers modified by the two systems were separately added to the resin in the same ratio and formed by die casting.The distribution of fibers in the resin in three cases was observed by SEM.It was proved that the modification of the polyimide fiber can reduce the agglomeration of the fiber in the resin and enhance the uniformity of the composite.The tensile properties and tribological properties of pure FEP resin and three composites were tested.The advantages and disadvantages of the three composites were discussed by comparing the mean and variance.Finally,polyimide fiber reinforced FEP resin composites have broad application prospects,but the research strength is far from enough,so in the subsequent research,it can continue to modify from polyimide fibers and polyimide monomers.Two aspects are designed to improve the uniformity and mechanical strength of the composite.