Analysis of Influence of Insulating Resin Paint Film on Enameled Wire Properties Based on Molecular Simulation

As one of the varieties of magnet wire, the enameled wire has excellent mechanical properties, heat resistance, ageing resistance, dimensional stability and chemical stability. This is one of the keys affecting the development of the electrical industry, especially the development of new motors. Different varieties of enameled wire insulating varnishes have advantages and disadvantages, in addition to their general properties. In order to improve the service life and reliability of the electrical coil of the motor, it is necessary to select the appropriate enameled wire reasonably according to different purposes. Molecular simulation technology can play a guiding role in the relationship between the molecular structure and properties of resins, help to understand the microscopic mechanism, shorten the experimental period, improve efficiency and save costs. In this paper, based on density functional theory (DFT) and molecular dynamics (MD), the microscopic properties of four insulating resins, polyamide–imide (PAI), polyester (PET), polyesterimide (PEI), and polyimide (PI), were studied. We also studied the influence mechanism of the insulating resin microstructure on the macroscopic properties of enameled wires, including adhesion, insulating properties and flexibility. The calculation results show that the polyester insulating enameled wire paint has good insulation performance and flexibility, the polyamide–imide paint has the best adhesion, and the polyimide insulating paint has very reliable insulation performance and flexibility. The performance research in this paper lays a foundation for the preparation of insulating resin coatings with better comprehensive properties. The performance research in this paper lays a foundation for preparing insulating resin paint with excellent comprehensive performance.