Preparation method of high insulation polyethylene material

The invention discloses a preparation method of a high insulation polyethylene material. The preparation method is characterized by comprising the steps of: (1) preheating polyethylene resin at the temperature of 70-80 DEG C for 10-15 minutes; and (2) removing impurities in the preheated polyethylene resin; (3) maintaining the temperature of 70-80 DEG C, adding a peroxide crosslinking agent and a multielement compound antioxidant into the heated polyethylene resin, stirring for 30-35 minutes and then standing still for 20-25 hours to obtain the finished product. The preparation method has the advantages that the obtained high insulation polyethylene material is good in extrudability and cabling property, and can be used for an insulating layer or jacket layer of a high-voltage power cable; and the preparation method is low in energy consumption and high in production efficiency, the hidden danger that the traditional melt granulating technology is overhigh in processing temperature and easy to pre-crosslink are eliminated, and the problems that uneven diffusion and distribution are uneven and the quality of the finished product is unstable are solved.