Al₂O₃ Nano filler’s impact on electrical, mechanical, thermal, microstructural and the chemical characteristics of liquid silicone rubber for composite insulators

Abstract

This study examines the function of Al2O3 nanofiller in liquid silicone rubber (LSR) for the purpose of outdoor insulation. Several characteristics, including structural (Field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), physical (density), mechanical (tensile, tear, percentage elongation at break, and shore A hardness), thermal (thermal conductivity, thermo gravimetric analysis (TGA)), electrical (dielectric constant, dielectric breakdown strength, DC volume resistivity, arc resistance, and recovery of hydrophobicity), although chemical (immersion of samples for 72 h in NaCl, HCl, and H2SO4 solutions and measurement of sample weight and PH of the solution before and after immersion) were investigated after the addition of Al2O3 nanofiller with different compositions, such as 5, 10, and 15 weight percentages. In comparison to pure LSR, it was discovered that the inclusion of nano Al2O3 particles enhanced the material’s density by 11%, thermal conductivity by 12%, dielectric constant by 24%, DC volume resistivity by 2%, arc resistance by significantly 1205%, dielectric breakdown strength by 54%, and hydrophobicity. Other improvements include a 7% rise in tensile strength, a 23% rise in tear strength, a 17% rise in hardness, and an 18% reduction in percentage elongation at break when compared to pure LSR for the composite samples. Mechanical qualities are affected by the curing process duration. More specifically, we discovered there is a proportionality relationship between the tensile strength and the elastic modulus. Findings of the chemical examination revealed that the composites have corrosion resistance in the form of negligible weight change in the sample when exposed to salt and acid solutions. The combination of these exceptional qualities makes Al2O3 composites appealing within an insulating materials realm.