侧链含氮原子磺化聚酰亚胺膜材料的制备及其性能研究  

Preparation and Characterization of Sulfonated Polyimide Membranes Containing Nitrogen Atoms in the Side Chain

作　　者：李玉邯[1] 金日哲[2] 高连勋[2] 

机构地区：[1]吉林工商学院实验中心,长春130062 [2]中国科学院长春应用化学研究所,长春130022

出　　处：《高分子学报》2014年第8期1096-1102,共7页Acta Polymerica Sinica

基　　金：国家自然科学基金青年基金(基金号20904052)资助项目

摘　　要：以对苯二酚为原料经过三步反应,合成了含叔胺取代基的二胺单体2,5-二((二甲氨基)亚甲基)-1,4-二(对氨基苯氧基)苯(DMAPB),并与1,4,5,8-四酸萘二酐(NTDA)、磺化二胺4,4'-二氨基二苯醚-2,2'-二磺酸(ODADS)高温聚合,通过改变磺化二胺单体(ODADS)的含量,制备了一系列具有不同磺化度的侧链含氮原子磺化聚酰亚胺.采用间甲酚为溶剂,通过溶液浇铸法制备成膜.由于将N-原子引入到聚酰亚胺的侧链,使得其与磺酸基更易形成较强的离子交联,从而有效地控制膜溶胀,提高了膜稳定性.新的磺化聚酰亚胺的热稳定性高达330℃并显示了良好的氧稳定性,其阻醇性能也得到了提高,在20℃下,膜的甲醇渗透系数为2.05×10-7至5.11×10-7cm2/s,远低于Nafion 117(2×10-6cm2/s)一个数量级.磺化度40%的磺化聚酰亚胺膜在100℃去离子水中测试1000 h以上仍能保持较好的机械性能.膜在高湿条件下也显示了良好的机械性能.然而,膜的质子传输率有所下降,这应该是较强的离子交联导致膜产生较致密的结构,减少了含水量并阻碍了水和H+的移动.同时,磺酸基与氮原子发生离子交联,减少了参与质子传输的磺酸基数量,降低了聚合物膜的酸性.A novel diamine monomer, 2,5-bis（N,N-dimethylamino）methyl）-1,4-bis （4-aminophenoxyl） benzene （DMAPB）, was synthesized. A series of sulfonated polyimide （SPI） were prepared from DMAPB, 1,4,5,8-naphthalenetetracarboxylic dianhydride （NTDA） and sulfonated diamine （ODADS）. By varying the molar ratio of the sulfonated diamine to the unsulfonated diamine, copolymers with 40% - 80% sulfonation degree were obtained. The SPI membranes were obtained via solution casting with m-cresol as the solvent. The nitrogen atoms introduced in the side chains of the SPI could effectively resist membrane swelling due to the strong interchain interactions through basic nitrogen atoms and sulfonie acid groups. The copolymer SPI-40 showed higher water stability,it could maintain mechanical strength after being soaked in 100 ℃ liquid water for more than 1000 h. The copolymers were thermally stable up to 330 ℃ and displayed good oxidative stability. The membranes exhibit methanol permeability from 2.05 × 10-7 to 5.11 × 10^-7cm2/s at 20 ℃ , which was much lower than that of Nation （2 × 10-6cm2/s）. The SPI also showed reasonable mechanical strength under high moisture conditions. However, the cross-linked membranes showed lowered proton conductivities than the uncross-linked ones because that the crosslinking resulted in the more compact structure of membranes,which decreased the water uptake and hindered the mobility of water and H ^＋ . In addition, a part of the sulfonie acid groups was consumed during the cross-linking process.

关 键 词：磺化聚酰亚胺 酸碱交联 质子交换膜 燃料电池 

分 类 号：TM911.4[电气工程—电力电子与电力传动] TQ320.721[化学工程—合成树脂塑料工业]