磺化聚酰亚胺序列共聚物的合成与性能研究

Synthesis and property of sequenced sulfonated copolyimides

通过成醚反应制备了一种新型含砜基的萘酐：4,4＇-（砜基双（4,1-亚苯基）双氧）-双（1,8-萘酐）（SPNDA）。利用这种新的萘酐先与己二胺（HDA）反应形成疏水段,再与4,4＇-二（4-氨基苯氧基）-3,3＇-联苯二磺酸（BAPBDS）和1,4,5,8-萘四甲酸二酐（NTDA）共聚,合成了一系列磺化聚酰亚胺序列共聚物。所得的共聚物具有良好的成膜性,XRD表明了非晶相聚合物中存在部分准晶体。共聚物膜具有良好的化学稳定性和热稳定性,尺寸变化率和吸水率较文献中具有相似结构相同IEC的聚合物膜均有一定程度的减少。质子传导率80℃下达到0.11-0.16S/cm。

A novel sulfonyl-containing naphthalic dianhydride monomer, 4,4′- （ sulfonylbis （4,1-phenylene） bis （oxy） ） bis（1,8-naphthalenedicarboxylic anhydride）（SPNDA）,was successfully synthesized and characterized. A series of sulfonated copolyimides consisting of the hydrophobic polyimide blocks were synthesized by a two-step one-pot copolymerization technique. First the SPNDA was polymerized with excess of 1,6-hexanediamine（HDA）to yield amine-terminated polyimide oligomers HS（block length= 5 or 10）. Consequently the HS was further copolymerized with 1,4,5,8-naphthalenetetracarboxylic dianhydride（NTDA） and 4,4 ′-bis （4-aminophenoxy）-3,3 ′-biphenyldisulfonic acid （BAPBDA） to give the sequenced copolyimides. The synthesized copolyimides showed good film-forming ability and good thermal stability. XRD patterns revealed that the copolyimides had roughly amorphous morphology with quasi-crystalline component. Fenton＇s test revealed that the copolyimide membranes showed much higher radical oxidative stability than the corresponding sulfonated homopolymer. The proton conductivities of the membranes were in the range of 0.11-0.16 S/cm at 80 ℃ in deionized water.