芳香族系ポリイミドスルホン酸の合成と溶媒溶解性と膨潤挙動に関する共重合構造の効果

摘要

テトラカルボン酸無水物，二官能イオン性モノマーとして4,4'ジフェニルエーテル系スルホン酸モノマーと二官能非イオン性芳香族モノマーとして各種芳香族ジアミンモノマーを用いて，芳香族系ポリイミドスルホン酸の合成を行い，溶媒溶解性とアルカリ性に対する溶解挙動を調べた.モノマーの構造により，m-クレゾール，DMSO, NMP, DMFへの溶解挙動に大きな差が出た.モノマーの対称，非対称構造は溶媒溶解挙動に影響した.アル力リ水溶液への膨潤・溶解挙動は，二官能非イオン性芳香族モノマーによる共重合構造が大きく影響するが，六員環系の芳香族ポリイミドの加水分解性にも関係した静電的イオン遮蔽効果により考察した.%Naphthalene tetracarboxylic acid anhydride, sulfonated diphenyl ether diamine and non-ionic aromatic diamines were successfully co-polymerized to sulfonated polyimides, and their solvent solubility and swelling behavior in organic solvents of DMSO, NMP, DMF, and m-Cresol and in aqueous solutions of chloride, sodium hydroxides, as well as pure water have been examined. The asymmetric chemical structures of non-ionic aromatic diamines and the ratios of their copolymerization strongly impact on solvent solubility. The chemical structures of non-ionic aromatic diamines and the ratios of their copolymerization also affect the solubility and swelling behavior in alkaline solutions of lithium, sodium and potassium hydroxides. Their solubility and swelling behavior in alkaline solution were explained by the Hofmeister series and electrostatic shielding effect of ionic structures on sulfonated polyimide.