四个四catenar(L1-L4)和一个六catenar(L5)配体从diaza-18-crown-6框架衍生而来,进行了合成和表征。在这些配体,胺官能团装有苯甲酰氧基苄基连接基团,该基团与 羰功能(L1)或亚甲基桥(L2-L5)和带有不同长度的烷氧基链R:对于L2为R = OCH 3,对于L3和L5为OC 10 H 21,对于L1为OC 12 H 25,对于L4为OC 16 H 33。非同构配体 L1和L3–L5与各种镧系元素盐反应生成配合物,形成热致六方柱状相,这可以通过热,光学和热力学确定。小角X射线衍射方法。烷氧基链的长度(L3和L4)对介晶性能的影响不大,与连接基的功能,烷氧基链的数目,抗衡离子或镧系元素离子无关。最好的系统被证明是与L3的镧系镧系元素络合物,在100°C(La最高147°C)下呈现Col h相,熔融转变温度在58(La)至86(Tb)°C之间。在[Eu(NO 3)3
The influence of lateral fluorination and cyanation on the mesomorphism of polycatenar mesogens and the nature of the SmC phase therein
作者:Antonina I. Smirnova、Benoît Heinrich、Bertrand Donnio、Duncan W. Bruce
DOI:10.1039/c5ra17100h
日期:——
Several series of tetracatenar mesogens having different lateral substituents (–F, –CN, –CF3) on the central ring have been synthesised and their mesomorphism investigated by polarising microscopy, DSC and small-angle X-ray scattering methods.
The influence of lateral apolar substituents on the mesomorphic behaviour of tetracatenar liquid crystals
作者:A. I. Smirnova、N. V. Zharnikova、B. Donnio、D. V. Brus
DOI:10.1134/s1070363210070194
日期:2010.7
Several series of new tetracatenar mesogens consisting of a five-ring aromatic core and bearing one or more apolar lateral substituents in the central benzene ring of the molecule have been synthesized and their mesomorphism is characterized by polarization microscopy, differential scanning calorimetry, and X-ray diffraction methods. Introduction of one, two, or four methyl groups into these tetracatenar mesogens destabilized columnar organization typical of the long-chain homologs, but did not suppress smectic C and nematic phases. Introduction of larger substituents did, however, suppress lamellar organization (C15H31) or mesomorphism (tert-butyl) totally.