Organosilane crosslinked polyethylene insulation material for 20kV cable and preparation method thereof

Abstract

The invention relates to an organosilane crosslinked polyethylene insulation material for 20kV cables and a preparation method thereof. The insulation material comprises a material A, a material B and a material C, wherein the material A comprises the following components in parts by weight: 100 parts of polyethylene, 0.01-1 part of initiator, 0.2-5 parts of silane crosslinking agent and 0.01-0.5 part of antioxidant; the material B comprises the following components in parts by weight: 100 parts of polyethylene, 0.5-5 parts of catalyst, 1-30 parts of catalyst promoter and 0.1-0.5 part of antioxidant; and the material C comprises the following components in parts by weight: 100 parts of ethylene-octylene copolymer, 0.01-5 parts of processing aid and 0.2-5 parts of metal ion inhibitor. The preparation method comprises the following steps of: (1) respectively extracting the raw materials of the material A, the material B and the material C and then feeding into an extruder for mixing and pelletizing to obtain three types of granule materials; (2) extracting the three types of granule materials based on a proportion of 100:4-7:2-6 and then fully mixing; and (3) feeding the mixed materials into the extruder for extruding to obtain a finished product. The preparation method has high hydrolysis cross-linking speed, flexible processing technology and simple operation. The insulation material has high voltage withstanding grade and long service life.

Description

technical field [0001] The invention relates to a silane crosslinked polyethylene cable material and a preparation method thereof, in particular to a silane crosslinked polyethylene insulating material for 20kV cables and a preparation method thereof, belonging to the technical field of polymer materials. Background technique [0002] Polyethylene is a commonly used insulating material in wire and cable, but polyethylene is a linear macromolecule with poor heat resistance and environmental stress cracking resistance. Only after cross-linking to form a three-dimensional network structure can the physical and chemical properties of polyethylene change significantly. The mechanical properties and burning dripping phenomenon can be greatly improved, the environmental stress cracking resistance can be reduced or even disappeared, the temperature resistance level can be increased to 90°C, and the solvent resistance and chemical resistance can be significantly improved. [0003] Th...

AI Technical Summary

Problems solved by technology

[0005] The traditional two-step method to produce silane cross-linked polyethylene has the following disadvantages: 1. The process of silane grafting has side reactions of peroxide cross-linking, and the fluidity of graft A material is not good, so it is not easy to process

2. Silane cross-linked polyethylene needs to be hydrolyzed and cross-linked in a warm water bath or steam. Water molecules are polar, while polyethylene is non-polar. The diffusion speed of water molecules in polyethylene is slow, especially for 20kV cables. The insulating layer is thicker, and the time required for hydrolysis and crosslinking is particularly long

3. The silane XLPE insulation material produced by this two-step method has a low withstand voltage level, and is generally only suitable for XLPE insulated cables of 10kV and below