METHOD FOR PREPARING A SELECTIVELY PERMEABLE PROTECTIVE STRUCTURE

摘要

A method for preparing a selectively permeable protective structure comprising mixing an ethylene acid copolymer and an organic acid, wherein at least 50% of the acidic groups are nominally neutralised to salts, melt blending this composition with an ethylene/ (meth) acrylic acid/alkyl (meth) acrylate terpolymer optionally with an ethylene containing-polymer, contacting a substrate with the molten composition and cooling. The selectively permeable structure comprises a membrane having a moisture vapor permeation value of at least 200 g-mil/m2/24h and barrier to liquid water, and a supporting substrate.