title: Mechanisms on electrical breakdown strength increment of polyethylene by aromatic carbonyl compounds addition: a theoretical study.
abstract: A theoretical investigation is accomplished on the mechanisms of electrical breakdown strength increment of polyethylene at the atomic and molecular levels. It is found that the addition of aromatic carbonyl compounds as voltage stabilizers is one of the important factors for increasing electrical breakdown strength of polyethylene, as the additives can trap hot electrons, obtain energy of hot electrons, and transform the aliphatic cation to relatively stable aromatic cation to prevent the degradation of the polyethylene matrix. The HOMO-LUMO energy gaps (E(g)), the ionization potentials (IPs), and electron affinities (EAs) at the ground states of a series of aromatic carbonyl compounds are obtained at the B3LYP/6-311+G(d,p) level. The theoretical results are in good agreement with the available experimental findings, show that 2,4-dioctyloxybenzophenone (Bzo) and 4,4'-didodecyloxybenzil (Bd) molecules can effectively increase the electrical breakdown strength when they are doped into polyethylene because of their much smaller E g values than all the other studied aromatic carbonyl molecules and excellent compatibility with polymers matrix.
authors.affiliation: Key Laboratory of Engineering Dielectrics and Its Application of Ministry of Education & College of Chemical and Environmental Engineering, Harbin University of Science and Technology, Harbin, 150080, People's Republic of China, hust_zhanghui11@hotmail.com.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Shang
authors.forename: Xuan
authors.initials: X
authors.lastname: Wang
authors.forename: Hong
authors.initials: H
authors.lastname: Zhao
authors.forename: Baozhong
authors.initials: B
authors.lastname: Han
authors.forename: Zesheng
authors.initials: Z
authors.lastname: Li