High-Performance Al2O3/Polyarylate nanocomposite paper with enhanced Insulation, thermal Conductivity, and environmental stability for Advanced electrical applications

Abstract

Polymer-based insulating paper is crucial for electrical equipment like transformers, high-power motors, and capacitors. However, as electronics evolve, current insulation papers fail to meet the demands for high insulation, thermal conductivity, and stability. This study introduces a novel nanocomposite paper with superior electrical strength, thermal conductivity, and weather resistance, made from self-produced polyarylate (PAR) nanofibers and Al₂O₃ nanoparticles. The high aspect ratio PAR nanofibers form a network that effectively captures Al₂O₃ nanoparticles, and thermoplastic properties of PAR enable thermal welding at the interface, minimizing defects. Experimental results demonstrate that when Al₂O₃ nanoparticles aggregate to a specific size and are fully encapsulated by PAR nanofibers (Al₂O₃ = 30 wt%), the resulting Al₂O₃/PAR nanocomposite paper exhibits superior insulation and thermal conductivity characteristics. It achieves electrical breakdown strength and thermal conductivity of 115.4 kV/mm and 2.726 W/(m·K), improving by 356 % and 2599 % over commercial aramid paper. Additionally, following 24 h of exposure to elevated temperatures (200°C) and ultraviolet (UV) treatment, the breakdown strength of commercial aramid paper decreased to 10.3 kV/mm and 9.3 kV/mm, respectively. In contrast, the Al₂O₃/PAR nanocomposite paper-maintained breakdown strengths of 101.6 kV/mm and 94.7 kV/mm, underscoring its excellent resistance to environmental degradation.