Tuning surface resistivity and thermal conductivity of water resistant fly ash waste based polymer composite via tailoring the interfacial polarization

High performance environment friendly industrial inorganic waste (fly ash) waste based water resistant electrical insulating hybrid composites are fabricated with very high surface and volume resistivity. Dielectric constant of hybrid composite was decreased significantly from 10900 to 4.98, 5.25, 5.00, 5.81, and 6.69 for filler concentrations of 10, 20, 30, 50 and 60% in epoxy matrix, respectively. Very high surface resistivity of 10¹³ Ohms/sq. and volume resistivity of 10¹⁴ to 10¹⁵ Ohms-cm with ultra-low water absorption of 0.14 % were achieved . Thermal conductivity analysis shows a slight increase in the thermal conductivity of the composite sheet and reaches the value of 0.4387 W/mK. Such high resistivity is attributed due to low dielectric constant and interfacial polarization and low water absorption in the samples. Our approach presents new, adaptable and cost-effective means for effectively utilizing waste as eco-friendly electrical and thermal insulating sheet and lowering the thermal loss in microelectronics.