Higher Order Structures and Electronic Properties of Poly(arylene vinylene) Thin Films

以获得较高的分子量和良好的稳定性为目标，合成了新型聚乙烯醇（PAV）前体聚合物。通过研究前驱体向PAV的转化程度和温度对膜链取向的影响，可以制备出高取向的聚（2,5-二甲氧基-对苯基乙烯）（MOPPV）和聚（2,5-对苯基乙烯）（PTV）薄膜。用光谱学方法对膜中的链取向进行了评价。取向薄膜的电导率、光电导率和三阶非线性磁化率chi^<(3)>均表现出较强的各向异性。沿链取向方向的电导率比垂直方向的电导率高5倍。与其他有机材料相比，MOPPV和PTV薄膜沿取向方向的(3)值极高，超过10^<-10> e.s.u。

New types of precursor polymers for poly(arylene vinylene) (PAV) were synthesized with the aims of attaining very high molecular weight and suitable stabilities.Highly oriented films of poly(2,5-dimethoxy-p-phenylenevinylene) (MOPPV) and poly(2,5-thienylenevinylene) (PTV) could be prepared through investigation on the effects of degree of conversion from precursor to PAV and temperature on chain orientations in the films. Chain orientations in the films were evaluated by the spectroscopic methods. Strong anisotropies were observed in the electronic conductivity, photo-conductivity, and third order nonlinear susceptibility chi^<(3)> of the oriented films. Conductivities along chain orientation direction have much higher values than those perpendicular to the direction by the factor of 5. The values of (3) along the orientation direction in MOPPV and PTV films are extremely high compared with those of other organic materials and exceeded 10^<-10> e.s.u.