DBD Plasma Treatment of Aramid Fiber to Improve Dielectric Property of Fiber-Reinforced Composites for GIS Insulation Rod

In this article, aramid fiber surface is treated by dielectric barrier discharge (DBD) plasma, and various aramid fiber reinforced epoxy composites (AFRCs) are prepared to investigate the effects of plasma modification on the dielectric and mechanical properties. It is found that plasma treatment could change the roughness and active chemical groups content of aramid fiber surface, which is beneficial to the improvement of interfacial bonding strength between fiber and epoxy resin. After appropriate plasma treatment of treatment time with 2 min and Argon flow rate with 2 L/min, the conductivity, dielectric loss, and integration charge
${Q}$
(
${t}$
) of AFRC are significantly reduced, and the breakdown strength is increased from 29.2 to 32.6 kV/mm. The shear strength is enhanced from 29.38 to 58.93 MPa. The improvement in the dielectric and mechanical properties of AFRC is attributed to the increased interfacial bonding strength and the reduced interfacial polarization. This article provides a way to improve the dielectric and mechanical properties of AFRC, which is of great significance for its application in insulation rod for gas-insulated metal-enclosed switchgear (GIS).