DDBT类可溶性聚酰亚胺的合成与性能研究

Synthesis and Properties of Polyimides from Dimethyl-3,7-diaminobenzathioplene-5,5-dioxide

由二甲基 5 ,5′ 3 ,7-二苯并噻吩二胺 (DDBT)和 3 ,3′ ,4 ,4′ -二苯砜四羧酸二酐 (DSDA)、2 ,2′ -双( 3 ,4 -二羧酸 )六氟丙烷二酐 ( 6FDA)、均苯四羧酸二酐 (PMDA)、联苯四羧酸二酐 (BPDA)等多种二酐单体进行缩聚反应制备了新型可溶性聚酰亚胺。测定了其特性粘度为 0 .6- 0 .9dL/g ;DDBT与DSDA、6FDA反应得到的聚酰亚胺在非质子强极性溶剂中具有良好的溶解性。用IR、热力学分析等手段对DDBT类聚酰亚胺进行了表征 ,并对可溶性DDBT -DSDA聚酰亚胺膜作了进一步的研究 ,推导出了苯在DDBT -DSDA聚酰亚胺膜中动态吸附初期的吸附方程。实验结果表明DDBT -DSDA聚酰亚胺膜对苯具有特殊的亲和力。

Condensation type polyimides were prepared by using DDBT (dimethyl 3,7 diaminobenzathioplene 5,5 dioxide) and several dianhydrdes such as pyromellitic dianhydride (PMDA), 3,3′,4,4′ biphenyltetracaboxylic dianhybride (BPDA), 2,2′ bis 3,4 [dicarboxyphenyl] hexafluorepropane dianhydride (6FDA) and 3,3′,4,4′ diphenylsulfone tetracaboxylic dianhydride (DSDA). The thermal decomposition temperatures and IR spectra of all DDBT based polyimides were studied. Polyimides DDBT DSDA and 6FDA DDBT, of which the intrinc viscositic in DMF range between 0.6?dL/g and 0.9?dL/g, are observed to be soluble in strong polar solvents. DSDA DDBT polyimide membrane shows high sorption ability for benzene, which is supposed to be ascribed to the high content of sulfonyl groups and their good affinity to benzene.