Enhancing surface insulation of glass fiber reinforced polymer composites by plasma fluorinating glass fiber

Glass fiber reinforced polymer (GFRP) is a widely used composite material in industrial production. In this article, glass fiber (GF) was fluorinated by dielectric barrier discharge (DBD), and the GFRP composites made of GF with different fluorination time and various numbers of fluorinated GF layers were prepared to improve the surface insulation property. The effect of plasma fluorination on GF was analyzed by scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS), including the surface morphology and chemical composition. In addition, the surface electrical properties of the above composites were investigated experimentally. The results show that the flashover voltage of modified GFRP is 29.84% higher than that of the original sample. By analyzing the charge dissipation and trap, it is inferred that plasma fluorination can raise the trap energy level of the composites, therefore suppressing the carrier migration on the surface and increasing the flashover voltage. Furthermore, the internal structure of composites can be improved by increasing the number of fluorinated GF layers, which accelerates the charge dissipation along the body, thus enhancing the surface insulation properties of the composites in both ways.