Study on discharge characteristics and improving surface hydrophobicity of epoxy resin by nanosecond pulse excited argon/hexamethyldisiloxane jet array

Abstract

Surface flashover of insulating materials induced by pollution and moisture environment is one of the main reasons for the damage of power system and electrical equipment. The improvement of the insulating materials surface hydrophobicity is key important, which can prevent the pollutants and water attachment, and enhance the insulating performance. In this paper, the super-hydrophobic film is formed on the surface of epoxy resin by a one-dimensional (1D) argon (Ar) jet array driven by nanosecond pulse power supply with hexamethyldisiloxane (HMDSO) addition. The influences of the processing time and HMDSO content on the epoxy resin surface hydrophobicity are investigated. It shows that with 0.04 % HMDSO, the jet array achieves a best hydrophobic treatment effect on the epoxy resin surface. After 60 s treatment, the apparent contact angle (ACA) of the epoxy resin surface increases from 60.3°of the untreated surface to 150.0°. The wettability of epoxy resin surface does not change too much as the treatment time beyond 60 s. The maximum ACA value 153.4°appears at 120 s processing time, which is just slightly higher than that of 60 s treatment time. The epoxy resin surface morphology and chemical feature before and after plasma processing are characteristics by the scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infra-red spectroscopy and X-ray photoelectron spectroscopy. It shows that the treated epoxy resin surface is covered with dense coral like particles in nanoscales, the original C=O、C-H and other organic functional groups are replaced by Si-(CH 3 ), Si-O-Si and other silicon containing groups, and the Si content increases from 0.4% to 28.0%. The experimental results provide important references to develop jet array as an efficient tool to enhance the surface hydrophobicity and insulating performance of insulating materials.

Microwave diagnostics of pulsed atmospheric discharge with electrolytic electrode and long‐lived luminous formation in its afterglow

“…By comparing Figure 5a,b, it is evident that the discharge current significantly decreases from its maximum value by the 50th ms. This period of time is very long, under normal circumstances, the pulse duration of pulse discharge is relatively short, usually in the order of nanoseconds [26,27]. The discharge plasma then ascends, forming an autonomous luminous object.…”

A double‐mode planar argon plume produced by varying the distance from an atmospheric pressure plasma jet

“…A plume wider than 1 cm has been achieved by incorporating a porous ceramic plate perpendicular to the gas flow [13]. To scale up the plume diameter, several jets are grouped together to form a jet array [14], in which only some discrete slim plumes have been produced due to interactions between adjacent plumes [15,16]. Through selecting the appropriate voltage polarity and tube material, the interactions between plumes can be suppressed, leading to a quasi line impact of the plasma on the target [17].…”

Discharge aspects of a snake‐like plasma plume generated by an atmospheric pressure plasma jet with variable argon flow rate

“…[ 1,2 ] The produced plasma in air ambient is also called a plasma plume, [ 3–6 ] in which there are abundant active species. [ 7 ] Due to its flexibility and low cost, plasma jet has become a promising tool for the applications in biomedicine, [ 8,9 ] material synthesis, [ 10–12 ] surface modification, [ 13–15 ] light source, [ 16 ] and water purification. [ 17–19 ]…”