Ethylene-vinyl alcohol copolymer composition, and preparation method therefor

Abstract

Described are an ethylene-vinyl alcohol (EVOH) copolymer composition, and a preparation method therefor. The composition contains an EVOH copolymer, element potassium, and element sodium, wherein the mass ratio of element sodium to element potassium is 0.1:1 to 1:1. By controlling the contents of element sodium and element potassium in an EVOH resin composition to fall within a specific proportion range, the heat resistance of the resulting EVOH resin composition is greatly improved, the initial decomposition temperature can be increased to 370-400° C., the maximum decomposition temperature can be increased to 400-440° C., and thus EVOH resin can adapt to the process requirement for a higher processing temperature. Moreover, further adding acyl-containing carboxylic acid and a phosphorus-containing compound/boron-containing compound can improve the thermal yellowing resistance of the EVOH resin composition, where the value of the yellowing index (YI) after 5-hour thermal treatment at 150° C., is increased by 15 or less.

Dependencies are inferred from the claim text.