化学学报 ›› 2007, Vol. 65 ›› Issue (21): 2499-2504. 上一篇    

研究简报

含全氟烃基的联苯酯类液晶的合成及其介晶性

汪必琴,王新玲,赵可清*,胡平   

  1. (四川师范大学化学与材料科学学院 成都 610066)
  • 投稿日期:2006-11-10 修回日期:2007-04-04 发布日期:2007-11-14
  • 通讯作者: 赵可清

Synthesis and Mesomorphism of Perfluoroalkyl Chain Containing Biphenyl Liquid Crystals

WANG Bi-Qin; WANG Xin-Ling; ZHAO Ke-Qing*; HU Ping   

  1. (College of Chemistry and Material Sciences, Sichuan Normal University, Chengdu 610066)
  • Received:2006-11-10 Revised:2007-04-04 Published:2007-11-14
  • Contact: ZHAO Ke-Qing

全氟烃或半氟烃链无手性液晶化合物可能呈现铁电液晶性, 具有较大的学术及应用价值而受到研究人员的重视. 合成了全氟己基苯甲酸联苯酯类液晶化合物: ROC6H4C6H4O2CC6H4C6F13 (3a3e), C3H7C6H4C6H4O2CC6H4C6F13 (6a)及其烃衍生物. 用差示扫描量热法(DSC)和偏光显微镜(POM)对其介晶性研究发现: 烃衍生物呈有序度较低的向列相, 熔点较高, 清亮点较低, 液晶相较窄. 全氟烃基取代的化合物出现多个有序度较高的近晶相, 熔点较低, 清亮点高, 介晶相温度范围宽.

关键词: 液晶, 4-丙基联苯酚, 全氟烃链, 亲氟效应, 疏氟效应

Perfluorinated or semi-perfluorinated alkyl chain containing achiral liquid crystals can display ferroelectric liquid crystalline properties, which have great potential applications to industry, therefore have attracted the attention of researchers. In this report, biphenylyl 4-perfluorohexylbenzoate liquid crystalline compounds ROC6H4C6H4O2CC6H4C6F13 and C3H7C6H4C6H4O2CC6H4C6F13, (R=CnH2n+1, n=6, 8, 10, 12, 16) have been synthesized. Their mesogenic behavior was investigated with differential scanning calorimetry (DSC) and polarized op-tical microscopy (POM). The results showed that the alkyl chain compounds exhibited nematic phases with higher melting points, lower clearing points, therefore narrower mesophase temperature ranges. The per-fluoroalkyl chain containing molecules showed highly ordered smectic phases with lower melting points, higher clearing points and broader mesophases.

Key words: liquid crystal, 4-propylbiphenyl-4'-ol, perfluoroalkyl chain, fluorophilic effect, fluorophobic effect