The cooperation between the modified polymer's carboxylic acidic groups, basic groups and grafted cyclodextrin can provide active barrier properties to a film, web, fiber or other polymer structure.

Abstract: Benzoic acid (BA) ligand was bonded on the side chains of polysulfone (PS) via a polymer reaction and obtained aryl carboxylic acid-functionalized polysulfone PSBA.

The present invention provides an industrially advantageous method for producing an unsaturated carboxylic acid-modified vinyl alcohol polymer, and a gas barrier film obtained by using the same.