ω-(4-甲氧基-4′-偶氮苯氧)溴代烷的制备及液晶性能的研究

Synthesis and Mesogenic Behaviours of 1-Bromo-ω-(4-methoxyazobenzene-4′-oxy)Alkans

偶氮苯及其衍生物是性能良好的介晶基团,含偶氮苯的分子有广泛的用途。文章报道了ω-(4-甲氧基-4′-偶氮苯氧)溴代烷(ZOn,亚甲基数n为2～6)的制备,所合成化合物的结构由红外光谱分析(IR)和核磁共振(1HNMR)测试确定。示差扫描量热(DSC)测试及偏光显微镜(POM)观察显示,产物ZO2未表现出液晶性,ZO3显双向液晶性,呈近晶相;ZO4、ZO5、ZO6呈单向液晶性,为向列相。它们的织构随n的增大而逐渐改善,ZO6的偏光织构最完善。

Azobenzene and its derivatives are widely used mesogenic groups.In this paper,1-bromo-ω-（4-methoxyazobenzene-4′-oxy）alkanes（ZOn）have been synthesized in which the number of methylene unit varies from 2to 6.The structures of the synthesized compounds were confirmed by IR and 1 H NMR spectroscopy.The differential scanning calorimetry （DSC）measurement and polarizing optical macroscope（POM）observation showed that the resulting compounds exhibited thermotropic liquid crystalline mesomophism except for ZO2.ZO3displayed semectic phase,and ZO4,ZO5and ZO6showed nematic phase.The texts pattern became more perfect with the increase of methylene number.