A Copolymer of Ethylene Vinyl Alcohol copolymer (Ethylene Vinyl Alcohol Copolymer) is a copolymer of ethylene and vinyl alcohol. EVA is formed by the copolymerization of ethylene and vinyl acetate, and then the acetic group is converted into hydroxyl group by saponification (hydrolysis) reaction to form ethylene-vinyl alcohol copolymer. Its structure combines the hydrophobicity of ethylene and the polar hydroxyl groups of vinyl alcohol, by adjusting the ratio of the two, can optimize the barrier and processing properties of the material, both the excellent barrier property of polyvinyl alcohol and the hot melt molding processing properties of polyethylene, belongs to the crystalline resin, with its excellent barrier properties, become the core material in high-end packaging and industrial fields.