Polyimide-co-polybenzoxazole copolymer, preparation method thereof, and gas separation membrane comprising the same

摘要

Disclosed herein are a polyimide-polybenzoxazole copolymer, a method for preparing thereof and a gas separation membrane comprising the same. More specifically, provided are a polyimide-polybenzoxazole copolymer simply prepared through thermal-rearrangement performed by thermally treating a polyimide-poly (hydroxyimide) copolymer as a precursor, a method for preparing the same, and a gas separation membrane comprising the same. The copolymer shows superior gas permeability and gas selectivity, thus being suitable for use in gas separation membranes in various forms such as films, fibers or hollow fibers. The gas separation membrane thus prepared can advantageously endure even harsh conditions such as long operation time acidic conditions and high humidity due to the rigid polymer backbone present in the copolymer.

主权项

1. A polyimide-polybenzoxazole (PBO-PI) copolymer having repeating units represented by Formula 1 below: wherein Ar1, Ar2′ and Ar3′ are identical or different, are each independently a bivalent C5-C24 arylene group or a bivalent C5-C24 heterocyclic ring which is substituted or unsubstituted with at least one substituent selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy, C1-C10 haloalkyl and haloalkoxy, or two or more of which are fused together to form a condensation ring, or covalently bonded to each other via a functional group selected from the group consisting of O, S, C(═O), CH(OH), S(═O)2, Si(CH3)2, (CH2)p (in which 1≦p≦10), (CF2)q (in which 1≦q≦10), C(CH3)2, C(CF3)2 and C(═O)NH; Ar2 and Ar3 are identical or different, are each independently a trivalent C5-C24 arylene group or a trivalent C5-C24 heterocyclic ring which is substituted or unsubstituted with at least one substituent selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy, C1-C10 haloalkyl and C1-C10 haloalkoxy, or two or more of which are fused together to form a condensation ring, or covalently bonded to each other via a functional group selected from the group consisting of O, S, C(═O), CH(OH), S(═O)2, Si(CH3)2, (CH2)p (in which 1≦p≦10), (CF2)q (in which 1≦q≦10), C(CH3)2, C(CF3)2 and C(═O)NH; Q is O, S, C(═O), CH(OH), S(═O)2, Si(CH3)2, (CH2)p (in which 1≦p≦10), (CF2)q (in which 1≦q≦10), C(CH3)2, C(CF3)2, C(═O)NH, C(CH3)(CF3), or C1-C6 alkyl-substituted phenyl or C1-C6 haloalkyl-substituted phenyl in which Q is linked to opposite both phenyl rings in the position of m-m, m-p, p-m or p-p; m is an integer of 10 to 400; and n is an integer of 10 to 400.