Polycyclic aromatic compounds surface modulation of TiO₂@SiO₂ nanoparticles enhances the insulation performance of polypropylene film

Abstract Polypropylene (PP) film is an important component of metallized film capacitors. However, the insulation issues of polypropylene film significantly affect the safe and stable operation of capacitors. In this study, polycyclic aromatic compounds (PAC) were introduced to the surface of TiO 2 @SiO 2 nanoparticles via chemical grafting, preparing Ti@Si-PAC nanofillers, to achieve modulation of the nanoparticle/PP interface. The experimental and simulation results indicate that Ti@Si-PAC/PP exhibits excellent insulation performance. The study indicates that the surface modulation of nanoparticles by PAC introduces a ‘soft interface’ between the nanoparticles and the polypropylene matrix. The ‘soft interface’ enhances the interfacial interaction, reduces dielectric loss, and introduces deep traps, exhibiting a significant inhibitory effect on carrier migration. Additionally, the introduction of PAC enhances the electron trapping capability in the interface region, which plays a positive role in quenching free radical chain reactions and reducing the damage of high-energy electrons to polypropylene molecular segments. This study provides an effective method for enhancing the insulation performance of polypropylene.