Non-Symmetric Liquid Crystal Dimers: High Thermal Stability in Nematic Phase Enhanced by Thiophene-2-Carboxylate Moiety

被引：26

作者：

Yeap, Guan-Yeow ^{[1
]}

Hng, Tiang-Chuan ^{[1
]}

Takeuchi, Daisuke ^{[2
]}

Osakada, Kohtaro ^{[2
]}

Mahmood, Wan Ahmad Kamil ^{[1
]}

Ito, Masato M. ^{[3
]}

机构：

[1] Univ Sains Malaysia, Sch Chem Sci, Liquid Crystal Res Lab, Minden 11800, Penang, Malaysia

[2] Tokyo Inst Technol, Chem Resources Lab, Midori Ku, Yokohama, Kanagawa 227, Japan

[3] Soka Univ, Fac Engn, Dept Environm Engn Symbiosis, Tokyo, Japan

来源：

MOLECULAR CRYSTALS AND LIQUID CRYSTALS | 2009年 / 506卷

关键词：

enantiotropic N phase; high thermal stability; non-symmetric liquid crystal dimers; thiophene; 5-N-ALKYLTHIOPHENE-2-CARBOXYLATES; OLIGOMERS;

D O I：

10.1080/15421400902987248

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Series of non-symmetric liquid crystal dimers, -(4-benzylidenechloroaniline-4'-oxy)--[4-(thiophene-2-carboxyl)benzylideneaniline-4'-oxy]alkanes incorporating a thiophene-based moiety in one of the two mesogenic units have been synthesized and characterized. The nematogenic properties of the dimers were studied wherein the flexible spacers made up by n methylene units (-CH2-) ranging from n=5 to n=12. These dimers exhibit enantiotropic N phase with high thermal stability (187.0 degrees C). The N phase temperature range for the present homologues is found to be strongly dependent on the length and parity of the methylene spacer which connects the 4-benzylidenechloroaniline and 4-(thiophene-2-carboxyl)- benzylideneaniline mesogenic cores.

引用

页码：134 / 149

页数：16

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