Preparation And Properties Of Carbon Fiber Reinforced PES-C Composites

High property thermoplastic resin matrix composites have been extensively used in thefield of aerospace and aviation because of their inherent properties such as high strength,modulus, temperature and low density. PES-C is a high property thermoplastic resin withhydrolysis resistance, acid and alkali resistance, thermal stability, and can be dissolved in thespecific organic solvent, which is the ideal choice for matrix resin. PAN-based carbon fiber isthe reinforcing material. For poor adhesive condition between carbon fiber and PES-C, we cansolve the problem by using Radio frequency plasma processing method.In this paper, we use the low-temperature oxygen plasma to modify surface of carbonfiber by adjusting the processing time and plasma processing power300W unchanged todetermine the best treatment process. We test the polar group content of carbon fiber surfaceby XPS,observe the surface morphology of carbon fiber by AMF, test the carbon fiber/PES-C composite mechanical properties by universal testing machine, observe the bondingcondition between carbon fiber with PES-C and broken morphology of material by SEM.During the plasma treatment, we keep the power constant and adjust the process time.thenumber of the polar groups(C N, C O C, COOH) in surface of carbon fiber areimproved; polar groups/the non-polar groups enhances from0.49to0.63and the roughnessand surface area of carbon fiber in which there are many groves are increased. The activity,roughness and wettability of the carbon fiber surface are improved with the plasmatreatment,so that the adhesive properties between carbon fiber with PES-C is improved. ILSSand Flexural Strength of carbon fiber/PES-C composites with plasma treatment are100.93MPa and1473.53MPa,which are increased by24.91%and19.55%relative to thecomposite materials without plasma treatment. The SEM images of Interlaminar shear andflexural failure show that the interface failure mode is changed by plasma treatment. Researchshows that chemical bonding effect and mechanical interlocking effect are both favorable onthe interfacial adhesion between carbon fiber with PES-C resin, while the mechanical interlocking effect is more pronounced. So the best treatment time is15min.The effect of plasma modification on the hot and humid resistance properties ofcomposite is tested. The results shows that water absorption speed of composites with plasmatreatment is slow and saturated water absorption is0.71%, which comparing with compositeswithout plasma treatment drops17.4%.The mechanical properties of composite materials hasdeclined after absorbing water, but the strength retention plasma treatment of composite withplasma treatment comparing to composites without plasma treatment improves5.4%.Socomposite material with plasma treatment is more dense, the porosity is smaller, and hot andhumid resistance properties of composite is improved.