Molecular dynamics-based synergistic enhancement of electro-thermo-mechanical properties of nanocomposite aramid insulating papers

Abstract

To address the challenge of synergistically optimizing transformer insulation paper's dielectric and thermodynamic properties, a multi-scale collaborative design method was proposed to integrate molecular dynamics simulations and wet-forming processes, thereby developing high-performance nanocomposite aramid insulation materials. Using the COMPASSIII force field, composite models of nine nanofillers (including SiO₂, TiO₂, and C₃N₄) were constructed. Through non-equilibrium molecular dynamics thermal conductivity simulations, mechanical parameter calculations, and dielectric performance analysis, SiO₂, TiO₂, and C₃N₄ modified with the silane coupling agent KH570 were identified as the optimal modification systems. Experimental results demonstrate that the KH570-modified SiO₂ system with 15 % doping achieves a synergistic breakthrough in mechanical and dielectric properties: Tensile strength increases by 30.25 % to 9.73kN/m, and dielectric strength improves by 27.78 % to 30.31 kV/mm. The C₃N₄ system exhibits a dielectric strength of 33.29 kV/mm at 4 % doping. The TiO₂ system achieves an optimal balance between mechanical and dielectric properties at 3 % doping. Simulations and process optimization validate the feasibility of nanofiller doping in achieving coordinated regulation of electrical-thermal-mechanical multi-properties in insulation paper, offering insights for designing high-voltage equipment insulation materials