Influence of Corona Ageing on Electrical and Mechanical Behaviour of Epoxy Micro-Nanocomposites

Epoxy micro-nanocomposites prepared with addition of silica micro-particles and IXEPLAS® nanofillers are exposed to corona phenomenon for different durations to understand its impact on the electrical as well as mechanical properties. Corona inception voltage (CIV) has been determined by adopting UHF and fluorescence techniques. The CIV values tend to reduce significantly after corona ageing. Surface potential decay analysis showed an increment in decay rate of surface potential. Left shift of trap density curves has been observed with increment in corona ageing period. From atomic force microscopy (AFM) analysis, significant raise in mean surface roughness is noticed with respect to corona ageing period. Reduction in storage modulus and glass transition temperature are noticed with increment in corona ageing period, from dynamic mechanical analysis (DMA).