侧链含硫的联苯四酸二酐及其聚酰亚胺的合成

Synthesis of polyimides based on biphenyltetracarboxylic dianhydrides with thiophenyl pendent groups

以3,3′,4,4′-联苯四酸二酐(BPDA)为原料合成了2,2′-苯硫醚-4,4′,5,5′-联苯四酸二酐,然后分别与对苯二胺和4,4′-二胺基二苯醚通过高温缩聚法制备出两种侧链含硫的新型聚酰亚胺(PI)(PI-1和PI-2)。与文献报道的直接由BPDA为二酐制备的PI相比,PI-1和PI-2均表现出良好的有机可溶性。热重分析表明,PI-1和PI-2在氮气氛围下失重5%的温度分别为434,402℃;由差示扫描量热法分析得其玻璃化转变温度分别为297,286℃。

2,2＇-dithiophenyl-4,4＇,5,5＇-biphenyltetracarboxylic dianhydride was synthesized from 3,3＇-4,4＇- biphenyltetracarboxylic dianhydride （BPDA）. Two kinds of novel polyimides （PI） （PI-1 and PI-2） containing thiophenyl＇ pendent groups were prepared through high-temperature polyeondensation between the resultant dianhydrlde and p-phenylenediamine or 4,4＇-diaminodiphenyl ether. Both the PI-1 and PI-2 exhibited superior organo-solubility in comparison with PI obtained directly from BPDA as dianhydride reported in literatures. The 5% mass loss temperature in nitrogen of PI-1 and PI-2 was 434 ℃ and 402 ℃, respectively. Their glass transition temperature was at 297 ℃ and 286 ℃, respectively