Ethylene-vinyl alcohol copolymer and aqueous solution using same

Abstract

An ethylene-vinyl alcohol copolymer may have an ethylene unit content of 1 mol % or more and less than 15 mol %, a saponification degree of 85 mol % or more and less than 99.9 mol %, and a viscosity-average degree of polymerization of 200 or more and less than 3000. The copolymer may contain a molecule containing a structure (I) Y being H or —CH3, at an end; and a molecule containing a structure (II) Z being H or —CH3, at an end, a total content of the structure (I) and the structure (II) in all monomer units is 0.001 mol % or more and less than 0.1 mol %, and a molar ratio R [I/(I+II)] of the structure (I) to the total of the structure (I) and the structure (II) satisfies formula (1): R < 0 . 9 ⁢ 2 - Et / 1 ⁢ 00 , ( 1 ) Et being ethylene unit content (mol %).

Dependencies are inferred from the claim text.