The deterioration mechanism of the mechanical and electrical properties of insulating cardboard under mechanical force

In this paper, we constructed the cellulose model of insulating cardboard, studied the changing process of the micro performance index of insulating paper under the action of mechanical force, and designed the mechanical force aging experiment under different aging times, and studied the mechanical properties, electrical properties, and conducted micro morphology observation of the aging sample. Simulation results showed that mechanical force can aggravate the movement of insulating cardboard fiber chain and cause decreased cellulose stability. The measurement results show that among mechanical properties, the degree of polymerization of insulating cardboard was decreased; among electrical properties, the discharge inception voltage of insulating cardboard after aging decreased, and the discharge amount at a similar external voltage increased. SEM observation of aging samples revealed that mechanical forces induced fiber refinement, bifurcation, and fracture on insulating cardboard surfaces. This paper expounds the degradation mechanism of the insulating paper properties from macro perspective and micro-prospective, which provides a reliable basis and data support for the subsequent insulation ability judgment of the insulating cardboard.