Chemical crosslink polyethylene insulating plastic used for water tree resistant power cable and application thereof

Abstract

The invention discloses a chemical crosslink polyethylene insulating plastic used for a water tree resistant power cable and application thereof. The insulating plastic comprises the components based on the parts by weight: 100 parts of polyethylene resin, 0.5-4 parts of ethylene-acrylic ester multipolymer, 1.0-3.0 parts of peroxide, 0.02-2 parts of compound antioxidizer, 0.1-0.5 parts of nucleating agent and 0.1-1 part of siloxane. The chemical crosslink polyethylene insulating plastic used for the medium-low pressure water tree resistant power cable has good extrudability and cable forming property, less impurity content, excellent water tree resistant performance, improved internal lubricity and good surface performance; under the same current, the extruded velocity of the cable is high, the processing temperature is reduced, less low molecular gas is generated, the impurities and defects inside the material get less, the degree of crystallinity and the water tree resistant performance are improved, the production energy consumption is reduced, and the production efficiency is improved. Therefore, the invention can be used for an insulating layer or a restrictive coating of medium-low pressure power cable.

Description

technical field [0001] The invention relates to a chemically cross-linkable polyethylene insulating plastic for water-tree-resistant power cables under medium and low voltages and its use. Background technique [0002] Water trees are the main cause of insulation failure of medium and high voltage XLPE cables. Therefore, the study of XLPE cable materials resistant to water branches has important economic value for improving the quality of XLPE cable insulation in my country. [0003] The place where water trees are produced is accompanied by the presence of space charges. The space charge effect of XLPE insulation is the main factor restricting the dielectric strength of power cable insulation. Many researchers have found that adding a small amount of polar groups to polyolefin compounds can greatly reduce the space charge accumulation in the insulation, and can also significantly reduce the probability of electrical tree formation. The copolymer of ethylene and acrylate,...

AI Technical Summary

Problems solved by technology

[0005] The current chemically cross-linked polyethylene insulating plastics used for anti-water tree power cables, such as Dow's HFDB-4202NT EC material, have the following defects: the internal lubricity of the material is poor, and a higher processing temperature is required, which increases the pre-heating temperature. Cross-linking hidden dangers, so that there are more defects and voids inside the material