Space Charge and Breakdown Strength Behaviour of PP/POE/MgO Nanocomposites

Abstract

Polypropylene (PP) is considered a competitive candidate to replace widely used cross-linked polyethene (XLPE) in cable material application, as it can potentially withstand higher operating temperature and has excellent electrical properties. Besides, it is a more environment-friendly material, since PP does not require crosslinking and, therefore, can be easily recycled at the end of its life. This paper investigated the influence on the tensile strength, space charge and breakdown behaviours of the PP by adding polyolefin elastomer (POE) and Magnesium Oxide (MgO) nanoparticles. 10 or 20 wt. % of POE and 5 or 10 wt. % of nano-MgO were introduced into PP. Results show that the PP with 10 wt. % of PE02 and 5 wt. % of surface treated-MgO has the highest breakdown strength among all systems. Also, the introduction of POE and nano-MgO can significantly improve the mechanical flexibility. In combination with the observed suppression of space charge accumulation, which shows that PP/POE/MgO nanocomposites are a viable option for high voltage (HV) cable insulation material in the future.

Influence of thermally induced self‐assembly shish‐kebab crystal on charge transport behaviour in polypropylene/elastomer blends

“…where δ is the average hopping distance, ϕ is the average hopping barrier height. The measurement results are fitted by numerical fitting method according to the formula (7) and (8). The average hopping distances for all the samples are obtained and listed in Table 2, which is in the reasonable range of 5-20 nm, hence it is proposed that the hopping conduction model is suitable to describe the charge transport behaviour for PP and its blends in this work.…”

“…where δ is the average hopping distance, ϕ is the average hopping barrier height. The measurement results are fitted by numerical fitting method according to the formula (7) and (8).…”

“…Charge transport behaviour has attracted much attention in the research field of electrical insulation materials [5][6][7][8][9][10][11][12]. That is a microcosmic expression to evaluate electrical properties of materials, which is closely related to the microstructure and the crystal structure of materials [13].…”

“…Many investigations have been performed in order to improve the electrical performance of PP/elastomer blend. J. W. Zha the doping of metallic oxide nanoparticles into PP/elastomer blend could effectively suppress the accumulation of space charge and improve the breakdown strength [5][6][7][8]. However, the large concentration of nanoparticles could lead to the agglomeration, which introduces the physical defects into the insulation.…”

Effect of β‐nucleating agents on the crystallization behavior and force‐electric properties of the polypropylene blends

“…[9][10][11][12] Among them, POE materials have excellent electrical properties, processing properties, and heat and cold resistance properties, which are favored by scholars. 13,14 As a semi-crystalline thermoplastic material with high crystallinity, the crystallization behavior of polypropylene has a close correlation with the macroscopic force-electric properties of the material, and changing the crystallization behavior of polypropylene is bound to have an obvious effect on the properties of polypropylene. Therefore, improving the properties of the blends by changing the crystallization behavior of polypropylene is also a feasible direction for improvement.…”