化学学报 ›› 2009, Vol. 67 ›› Issue (11): 1231-1236. 上一篇    下一篇

研究论文

棒状双酯基磁性液晶的合成及其磁性和液晶性

郑敏燕*,a 安忠维b 魏永生a

  

  1. (a咸阳师范学院化学系 陕西 咸阳 712000)
    (b陕西师范大学化学与材料科学学院 陕西 西安 710062)

  • 投稿日期:2008-10-16 修回日期:2008-12-08 发布日期:2009-06-14
  • 通讯作者: 郑敏燕

Synthesis of Rod-like Bis-ester Magnetic Liquid Crystals and Their Magnetic and Liquid Crystalline Properties

Zheng, Minyan *,a An, Zhongwei b Wei, Yongsheng a

  

  1. (a Department of Chemistry, Xianyang Normal University, Xianyang 712000)
    (b School of Chemistry & Material Science, Shaanxi Normal University, Xi’an 710062)
  • Received:2008-10-16 Revised:2008-12-08 Published:2009-06-14
  • Contact: Zheng, Minyan

以端基为C3及C5取代的多环酸为原料, 合成了6个具有双酯基中介核, 末端为TEMPO (TEMPO=2,2,6,6-tetramethylpiperidine-1-oxyl)的磁性分子. 用元素分析, 红外光谱, 质谱等对其结构进行了表征; 利用超导量子干涉仪(SQUID磁学测量系统), 顺磁共振仪, 差热扫描量热仪以及热台偏光显微镜等对化合物的磁性质和液晶性质进行了测定, 提出了该类化合物同时具有磁性及液晶性所应具备的分子结构; 最后, 将磁性液晶与液晶材料进行了混配, 测试了混配液晶的光电性能. 结果表明, 6个化合物均同时具有磁性和液晶性, 其液晶相温度区间在16~24.8 ℃, 呈典型的向列相织构; 磁性液晶与液晶材料混配后可明显改善液晶材料的响应灵敏度.

关键词: 磁性液晶, 酯类, 4-OH-TEMPO, 光电性能

Six novel rod-like bis-ester magnetic liquid crystals have been prepared, in which bis-ester mesogenic cores with n-propyl and n-pentyl substituents were terminated by TEMPO free radical (TEMPO=2,2,6,6-tetramethylpiperidine-1-oxyl). Their structures were confirmed by elemental analysis, IR and MS. Their magnetic and crystalline properties were determined by a superconducting quantum interference device (SQUID), an electron paramagnetic resonance (EPR) spectrometer, a differential scanning calorimeter (DSC) and a heat stage polarizing optical microscope (HS-POM). Based on those determinations, the molecular structures of those magnetic molecules possessing liquid crystalline property were deduced. The photoelectric property of liquid crystal materials mixed with bis-ester magnetic liquid crystal molecules was also detected. The results show that the six compounds all have both magnetic and crystalline properties; their textures belong to nematic and the temperature range of mesophase is about 16 to 24.8 ℃; and the magnetic liquid crystal molecule could obviously improve the response sensitivity of liquid crystal materials.

Key words: magnetic liquid crystal, ester, 4-OH-TEMPO, photoelectric performance