- Method for preparation of crosslinked thermally rearranged polybenzoxazole-co-imide for gas separation and gas separation membranes prepared thereby

摘要

The present invention relates to a process for preparing a heat-converted poly (benzoxazole-imide) film having a crosslinked structure by thermal conversion at the same time as crosslinking by heat treatment of an ortho-hydroxypolyimide film having a carboxylic acid, . According to the present invention, a heat-converting poly (benzoxazole-imide) film having a cross-linking structure for gas separation can be produced only by a chemical process for forming a cross-linked structure and a complicated process such as UV irradiation, , The gas separation membrane produced thereby has excellent permeability and selectivity as well as a simple production process and commercialization by mass production is possible.