主链含长柔性链的聚酰亚胺的合成与性能研究

A STUDY ON THE SYNTHESIS AND PROPERTY OF POLYIMIDES WITH LONG FLEXIBLE CHAINS IN THE MAIN CHAIN

以α，ω二（４氨基苯氧基）ｎ烷与六氟叉丙基二（３，４邻苯二甲酸酐）缩聚并经化学亚胺化合成了主链含长柔性链的聚酰亚胺。该类聚酰亚胺在ＤＭＡ，ＤＭＦ，ＮＭＰ，ＴＨＦ，间甲酚，氯仿中有很好的溶解性，且与柔性链的长度无关。它们的玻璃化转变温度随柔性链的加长而明显降低，而耐热性能由于柔性链的加入而有所下降，但与柔性链的长度无明显关系。

Polyimides having long flexible chains in the main chain were prepared by the condensation of α,ω di(4 aminophenoxy)alkane and hexafluoroisopropylidene bis(3,4 phthalic anhydride) followed by a chemical imidization.The resultant polyimides are soluble in DMA, DMF, NMP, THF,m cresol and chloroform. The glass transition temperature of the polyimide exhibits an obviuos decrease with the increase of the length of the flexible chain. The thermal resistance of the polyimide is decreased because of the existence of the long flexible chain but almost independent of its length.