ETHYLENE-VINYL ALCOHOL COPOLYMER, RESIN COMPOSITION, AND MOLDED ARTICLE USING SAME

摘要

The present invention provides: an ethylene-vinyl alcohol copolymer having an exceptional appearance and minimized occurrence of discoloration, film defects, and film flaws such as streaks, together with having exceptional long-run workability during melt molding; a resin composition; and a molded article thereof. The present invention is an ethylene-vinyl alcohol copolymer (A) obtained by saponifying a copolymer of ethylene and vinyl ester, wherein the ethylene-vinyl alcohol copolymer (A) is characterized in that the molecular weight measured using a gel permeation chromatograph equipped with a differential refractive index detector and an ultraviolet-visible light absorbance detector satisfies the conditions represented by formula (1) after 50 hours of heat treatment at 220°C in a nitrogen atmosphere. (Ma - Mb)/Ma < 0.45 ... (1) Ma: equivalent polymethyl methacrylate molecular weight at the maximum value of the peak measured by the differential refractive index detector; Mb: equivalent polymethyl methacrylate molecular weight at the maximum value of the absorption peak at a wavelength of 220 nm as measured by the ultraviolet-visible light absorbance detector