Flame resistive silicone elastomeric powder-based coatings with excellent localized dielectric breakdown strength, loss tangent and thermal stability for electrical insulation

Experimental results suggested that the introduction of montmorillonite (MMT) nanoclay powder and chopped glass fibre (CGF) substantially enhanced the flame retardancy and thermal stability of silicone/ aluminium hydroxide (ATH) powder-based coatings. It was evidenced by the fire growth index (FGI) reduced to 0.401 in SE from 1.243 kW.m−2.s−1 in SB and the fire performance index (FPI) increased to 2.592 in SE from 0.661 s.m2.kWs.m2.kW−1 in SB. Enhanced Ts, T20%, T30%, T35%, T40%, Tf and residual percentage weight depicted the excellent thermal stability of SE relative to SB and SA. Dielectric breakdown strength (BDS) of coatings reduced with additives and measured at 19.12 in SE relative to 28.02 in SB and 21.86 kV/mm in SA. Moreover, Tan ẟ was measured at 0.0099 in SE at power frequency, whilst it was computed at 0.0267 and 0.0028 in SB and SA, respectively. Comparatively, SE could be a promising coating with excellent fire, thermal and dielectric parameters to be used in the electrical insulation applications.