| 초록 |
Aromatic polybenzoxazole and polypyrrolone belong to a class of ultra rigid-rod polymers. Both polymers have not only an outstanding chemical, mechanical and thermal stability, but also are well known for gas separation applications at high temperature. To date, many efforts to improve thermal stability of polymeric membranes have been studied to develop the gas separation performance. For this reason, copolymer between polybenzoxazole and polypyrrolone was chosen in this study. A series of novel poly(benzoxazole-pyrrolone) copolymers were prepared using 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), with two types of diamines: 2,2'-bis(3-amino-4-hydroxy-phenyl)hexafluoropropane (APAF) and 3,3'-diaminobenzidine (DBZ). Firstly, poly(amino amide acid) and poly(amic acid) were prepared by the direct condensation in N-methyl-2-pyrrolidinone (NMP) and the membrane was made in a conventional manner. And then, we built a poly(pyrrolone-hydroxyl imide) using thermal treatment up to 573K. Finally, a poly(pyrrolone-hydroxyl imide) was converted to poly(benzoxazole-pyrrolone) at 723K. The properties of poly(benzoxazole-pyrrolone) copolymer were characterized using FTIR, TGA, BET, and WAXD. From these results, we confirmed that poly(benzoxazole-pyrrolone) copolymer was successfully synthesized. |
