CROSSLINKED THERMALLY REARRANGED POLY(BENZOXAZOLE-CO-IMIDE), GAS SEPARATION MEMBRANES COMPRISING THE SAME AND PREPARATION METHOD THEREOF

摘要

The present invention relates to a thermal conversion poly(benzoxazole-co-imide) having a cross-linked structure by transesterification cross-linking reaction and succeeding thermal conversion of an ortho-hydroxy polyimide copolymer and a diol-based compound, to a gas separation membrane (except a fuel gas separation membrane) comprising the same, and to a preparation method thereof. The thermal conversion poly(benzoxazole-co-imide) having a novel cross-linked structure prepared according to the present invention has a structure in which polymer chains are less packing and more spaces are formed so that small molecules can be penetrated and diffused. The separation membrane comprising the thermal conversion poly(benzoxazole-co-imide) having the novel cross-linked structure has excellent gas permeability and selectivity and shows gas separation performance exceeding the 2008 upper bound related to carbon dioxide/methane separation.