Characteristics of electrical treeing in LDPE intruded by polymer films at AC voltage

In order to study the characteristics of electrical treeing aging at AC voltage in LDPE, with the continuous applied voltage to observe the propagation of electrical treeing, we adopted needle plane specimens to observe the treeing experiments. Meanwhile, the barriers of different polymeric films were introduced to the LDPE between the needle and the plane electrode, and characteristics of electrical treeing propagation of pure LDPE with the barriers were compared. The results show that electrical treeing propagation can be slowed down when introducing the barrier between two the electrodes, and can increase time to breakdown significantly. The effect depends upon the space charge and the barrier of different polymeric films used, their structures, and the binding forces of the interface to the surrounding LDPE and polymeric films.