合成了6个含偶氮基团的具有不同苯环个数的不对称弯曲型液晶分子,用1H NMR、HRMS表征其结构,采用差示扫描量热法(DSC)和偏光显微镜(POM)研究其液晶性能.考察结果表明:所有化合物均出现了液晶相,特别是含有3个苯环的分子在较低温度下出现了向列相;偶氮基团的吸收光谱在330～360 nm出现了较强的由π-π电子跃迁引起的吸收,在430～450 nm出现了较弱的由n-π电子跃迁引起的吸收,其吸收波长的变化表明分子的弯曲形状和电子分布使分子吸收波长有较大的变化.
参考文献
| [1] | Acharya B R,Primak A,Kumar S.Biaxial nematic phase in bent-core thermotropic mesogens[J].Phys.Rev.Lett.,2004,92(14):145506. |
| [2] | Prasad V,Kang S W,Suresh K A,etal.Thermotropic uniaxial and biaxial nematic and smectic phases in bent-core mesogens[J].J.Am.Chem.Soc.,2005,127(49):17224-17227. |
| [3] | Jang Y,Panov V P,Kocot A,et al.Optical confirmation of biaxial nematic (Nb) phase in a bent-core mesogen[J].Appl.Phys.Lett.,2009,95(18):183304. |
| [4] | 朱斌,黄佩,胡兰萍,等.含希夫碱基团的不对称弯曲型液晶分子的合成和相变研究[J].液晶与显示,2010,25(3):305-310. |
| [5] | 黄佩,胡兰萍,沈冬.(恶)二唑类弯曲形液晶分子的合成[J].液晶与显示,2010,25(5):626-634. |
| [6] | 马青兰,黄远明.三苯环香蕉形液晶的合成和表征[J].液晶与显示,2010,25(2):161-165. |
| [7] | Rahman M L,Asik J,Kumar S,et al.Liquid crystalline banana-shaped monomers derived from 2,7-naphthalene:synthesis and properties[J].Liq.Cryst.,2008,35(11):1263-1270. |
| [8] | Lutfor M R,Hegde G,Kumar S,etal.Synthesis and characterization of bent-shaped azobenzene monomers:guesthost effects in liquid crystals with azo dyes for optical image storage devices[J].Opt.Mater.,2009,32(1):176-183. |
| [9] | Rahman L,Kumar S,Tschierske C,et al.Synthesis and pho toswitching properties of bent-shaped liquid crystals containing azobenzene monomers[J].Liq.Cryst.,2009,36(4):397-407. |
| [10] | Prasad V,Kang S W,Qi X H,et al.Photo-responsive and electrically switchable mesophases in a novel class of achiral bent-core azo compounds[J].J.Mater.Chem.,2004,14(9):1495-1502. |
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