Study on water droplet initiated discharges and charge trap characteristics of laser textured silicone rubber nanocomposites

Abstract

Abstract Silicone rubber micro‐nanocomposites were fabricated and laser texturing was performed on their surface to investigate super hydrophobic properties. Irrespective of type of texture (square, hexagon or diamond), the contact angle is almost the same but a marginal increase in contact angle is observed with increase in wt% of nano fillers in silicone rubber. Water droplet initiated corona inception voltage (CIV) is measured by fluorescence technique and the CIV tends to increase with texturing and is high under—DC followed with +DC and AC voltages. Fast Fourier Transform (FFT) analysis of the fluorescence signal due to corona discharge indicates that the energy content of the fluorescent signal lies in the range DC to 20 MHz. Surface temperature of the sample after water droplet initiated discharge is found to be high under DC rather than under AC voltages. Textured surface has a relatively lower temperature decay rate under AC and DC voltages profiles, compared to nontextured surface. The formation of shallow charge traps is predominant with the textured specimens. In general, the diamond and hexagonal micro textured surface specimen exhibit better performance in terms of water droplet initiated CIV, hydrophobicity, and surface potential decay characteristics.

Keywords

• corona
• fluoroscence signal
• laser texture
• nanocomposites
• silicone rubber
• surface potential