Odd-even Effect on Liquid Crystalline Behavior for C_3-Cyclotriveratrylene(CTV) Derivatives Containing Alkoxies with Different Lengths as Peripheral Groups  

作　　者：CHEN Dan-mei DONG Yan-ming SHEN Bing-xing YANG Xue-hui LI Yan-jie HU Xiao-lan 

机构地区：[1]Department of Materials Science and Engineering, Xiamen University, Xiamen 361005, P. R. China [2]College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China

出　　处：《Chemical Research in Chinese Universities》2009年第4期579-584,共6页高等学校化学研究（英文版）

基　　金：Supported by the National Natural Science Foundation of China(No.20774077);the Natural Science Foundation of Fujian Province,China(No.E0510003, E0710025);the Project of Science and Technology of Xiamen City,China(No.3502Z20055013)

摘　　要：A series of bowlic cyclotriveratrylenes（CTV） with peripheral groups with different lengths were synthesized.These compounds were investigated by diferential scanning calorimetry and hot stage coupled polarizing microscopy.Several CTV derivatives show thermotropic liquid crystalline properties.The experimental results of their thermotropic liquid crystalline behavior indicate that the clear points,the entropy changes of melting points,the crystallization temperatures,and their entropy changes all exhibited an evident odd-even effect except the melting points,which decreased monotonously with the increase of the length of the alkoxy groups.The parameter values of CTVs with even number carbon atoms were larger than those of CTVs with odd number.When the length of alkoxyl chains was even longer,a monotonous decrease occured.Nevertheless,in the case of the entropy changes of both melting points and crystallization temperatures,the effect was valid for all the six species,and therefore,the whole curves presented as a zig-zag form.A series of bowlic cyclotriveratrylenes（CTV） with peripheral groups with different lengths were synthesized.These compounds were investigated by diferential scanning calorimetry and hot stage coupled polarizing microscopy.Several CTV derivatives show thermotropic liquid crystalline properties.The experimental results of their thermotropic liquid crystalline behavior indicate that the clear points,the entropy changes of melting points,the crystallization temperatures,and their entropy changes all exhibited an evident odd-even effect except the melting points,which decreased monotonously with the increase of the length of the alkoxy groups.The parameter values of CTVs with even number carbon atoms were larger than those of CTVs with odd number.When the length of alkoxyl chains was even longer,a monotonous decrease occured.Nevertheless,in the case of the entropy changes of both melting points and crystallization temperatures,the effect was valid for all the six species,and therefore,the whole curves presented as a zig-zag form.

关 键 词：Cyclotriveratryleues（CTV） Bowlic liquid crystal Thermotropic liquid crystal Odd-even effect 

分 类 号：O753.2[理学—晶体学] O636.1