The invention relates to a low-temperature amino cross-linked modified self-polymerized microporous
polymer gas separation membrane, a preparation method and application, and belongs to the technical field of
gas separation membranes, and the preparation method comprises the following steps: 1) synthesizing a cross-linked
precursor polymer PIM-BM through a bromomethylation reaction; (2) preparing a membrane
casting solution from the PIM-BM and a micromolecular amine cross-linking agent,
casting, and volatilizing to form a membrane; and 3) carrying out heat treatment at 40-80 DEG C under a vacuum condition for 6-32 hours to form a cross-linked
network structure, wherein the thickness of the film is 40-120 microns. According to the invention, a covalent cross-linked network is constructed through a low-temperature Hofmann
alkylation reaction of an amine cross-linking agent so as to limit the movement of a
polymer chain segment; the strong CO2 affinity of amido (-NH2) realizes
dissolution selectivity compensation, and the
diffusion selectivity synergistic effect of an inherent micropore channel of PIM-BM is combined, so that the tradeoff limitation of permeability-selectivity of a traditional
gas separation membrane is broken through; the cross-linked structure can effectively improve the physical
aging resistance of the PIM-BM film, and has good long-term
continuous operation stability; the preparation process is low in low-temperature process
energy consumption, easy to scale, suitable for the fields of
coal-fired
flue gas CO2 capture,
natural gas purification and the like, and has industrial application potential.