In this study, the Q(t) method is used to evaluate the accumulated charge characteristics of several polymeric insulating materials with respect to the electric field and temperature. The accumulated charge characteristics obtained using the Q(t) method are analyzed in terms of their molecular structures and energy levels obtained through quantum chemical calculations. The results show that the deep trap depth formed by the constituent monomers hinders the migration of holes and electrons and suppresses charge accumulation inside the polymeric insulating material. Additionally, many conjugated double bonds form a strong planar structure with the $\pi$ bonds, which restricts intramolecular motion due to the bending and rotation of the bonds, and thus exhibits excellent heat resistance.