Yangzi Petrochemical successfully produced EVA semiconductive shielding material for the first time

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Recently, Yangzi Petrochemical successfully produced the new EVA (ethylene-vinyl acetate copolymer) semiconductive shielding material UE1930TK for the first time, becoming one of the few companies in China capable of manufacturing this product. It is understood that on June 13, Yangzi Petrochemical successfully carried out the trial production of UE2850TK, a new type of cable material made of EVA (ethylene-vinyl acetate copolymer) with a high vinyl acetate content and low melt index. Tests have shown that all specifications of the product meet the standards. This trial production has diversified the EVA product portfolio and enhanced market competitiveness. Products of this grade are mainly used in the field of halogen-free flame-retardant cables; currently, imported materials dominate the market. Compared with conventional EVA cable grades, this product has an even lower melt index, offering superior processability. EVA (ethylene-vinyl acetate copolymer) semiconductive shielding material is a special material used in the cable industry. It is primarily employed as a shielding layer for medium- and high-voltage power cables. This material plays a crucial role in ensuring uniform electric field distribution and preventing partial discharges in high-voltage cables. It exhibits excellent impact resistance, stress crack resistance, flexibility, high elasticity, and chemical stability. Additionally, it is recyclable, making it aligned with the trend toward environmentally friendly cables. Currently, high-end wires and cables are in growing demand as components for applications such as electric vehicle charging stations and ultra-high voltage power grids, and EVA has a variety of uses in cable materials. In low-smoke, halogen-free cable materials, the production of thick smoke and harmful gases when polyvinyl chloride cables burn has raised concerns about their safety, leading to rapid development in such materials. It is made using polyolefin materials (mainly EVA) as the matrix resin, with flame retardants such as hydroxides added. EVA is widely used due to the presence of polar groups; its addition ratio is generally between 10% and 30%, but it has low strength, so it is often mixed with materials like PE. Furthermore, irradiation crosslinking is suitable for crosslinking low-smoke, halogen-free polyolefin materials, which can improve the temperature resistance of cables; however, crosslinking agents need to be added and the antioxidant system adjusted. In semiconductive shielding materials, EVA has become the preferred base resin as it can accommodate a large amount of conductive fillers and is compatible with insulation layer materials. Additionally, EVA can also be used as an additive to enhance toughness or flexibility, improving the properties of cable materials such as PVC, EPDM, and HDPE; it can also be formulated as a compatibilizer to increase the elongation rate of products.