Space charges in ethylene-styrene copolymers irradiated by low-dose gamma rays

Abstract

Space charges in ethylene-styrene copolymers irradiated by low dose gamma -rays were studied from the results of DC conduction, thermal pulse current, thermally stimulated current and residual voltage measurements. The number of carriers induced by gamma -rays and escaping from recombination becomes smaller with an increase in styrene content. The reason for this is thought to be that styrene absorbs the energy of electrons and increases the average energy necessary for ionization. The relationship between gamma -induced space charges and the morphological state of styrene is also studied in three kinds of polymers (random and graft copolymers and polymer blend). It can be said that styrene must be dispersed uniformly and bonded with ethylene in order to fully utilize the electron energy absorption effect of a benzene ring.

Charge accumulation in election beam irradiated various polymers

“…In this case, the trapped electron must stay against the formed electric fields. It has been reported that the benzene rings included in polymers may play a role of trap sites [6]. Since PET and PS are included the benzene rings, the injected electrons are trapped at the benzene rings.…”

Enhanced electrical insulating properties of polyethylene by incorporating polyethylene‐g‐polystyrene graft copolymers

“…PS is both an important commodity polymer and an outstanding insulating material. Previous studies have reported that copolymers containing PS segments possess high breakdown strength resulting from the resonant energy dissipation property of the benzene ring 30–32 and almost no space charge accumulation can be found inside PS samples under high DC voltages 33 . As mentioned above, simple blending of the insulating matrix with PS is meaningless due to the immiscibility issue.…”

Doping and Irradiation Dependence of Electrical Conductivity of Fe3+and Ni2+Doped Polyvinyl Alcohol Films

“…Its electrical conductivity depends on the thermally generated carriers and the addition of suitable dopants [9,10]. In * corresponding author; e-mail: kumar973@rediffmail.com addition, γ-irradiation has become one of the most common process to change the electrical conductivity in polymers [11][12][13][14]. In this regard we have made an attempt to study the electrical conductivity of pure PVA, Fe…”