聚酰亚胺（PI）LB膜中长链单轴取向排列的AFM研究

A STUDY ON LONG CHAIN SINGLE-AXIS ORIENTATION OF PI MOLECULES IN PI LB FILMS BY AFM

采用ＡＦＭ来研究聚酰亚胺（ＰＩ）Ｌａｎｇｍｕｉｒ－Ｂｌｏｄｇｅｔｔ（ＬＢ）膜中长链取向排列的技术条件，首先获得了清晰的，稳定性很好的ＰＩＬＢ单／双层膜的ＡＦＭ图像，并对ＰＩＬＢ膜中分子水平的微结构进行了分析。随后比较了形成ＰＩＬＢ膜的两种亚胺化工艺，即溶液亚胺化方法和热亚胺化方法对大面积内分子取向排列的影响，为进一步改善工艺条件以尽早将其投入实用奠定了初步基础。

The microscopic molecular structure of a polyimide(PI)Langmuir-Blodgett(LB)film monolayer was studied by atomic force microscopy(AFM).An AFMimage of a PI monolayer on highly oriented pyrolytic graphite(HOPG)showingclearly the polymer chains was observed. The measured parameters in situ,forexample,the distance between oxygen atoms at successive bends is 1.4nm～1.9 nmand the bend angle is about 118 deg.,correspond with those from STM results bythe others.The procedure in which the PA3S(polyamie acid alkyl amine salt)film was converted to polyimide film by either the heating method or the solutionmethod is very important.The preliminary results of comparing these twotechnological processes observed by AFM indicated that the solution method ismore suitable for this PI LB film preparation in the usage of the future liquid-crystal display devices.