期刊
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
卷 111, 期 2, 页码 1483-1490出版社
SPRINGER
DOI: 10.1007/s10973-012-2504-2
关键词
Symmetric dimer; Isotropic-nematic transition; Nematic-SmA transition; Density measurements; Differential scanning calorimetry
资金
- Department of Science and Technology [SR/S2/CMP-0071/2008]
- DSTWOS-A [SR/WOS-A/PS-05/2010]
- CSIR, New Delhi
As a part of the systematic studies on symmetric liquid crystal dimer homologous series, alpha,omega-bis-(4-n-alkylaniline benzylidene-4'-oxy) alkanes, (referred to as m.OnO.m with m = 3, 4, and 5; and n = 8, 9, and 10), we present in this article the nature of phase transitions across isotropic-nematic and nematic-smectic-A (N-SmA) phases exhibited by the just mentioned compounds. The methods employed are differential scanning calorimetry and dilatometry. The compounds studied were 3.O8O.3, 4.O8O.4, and 5.O8O.5; and 3.O9.03, 5.O9O.5, 3.O10O.3, 4.O10O.4, and 5.O10O.5. Different from the case of their corresponding monomers, all these compounds exhibit a nematic phase only with the exception of 5.O8O.5 which exhibits a SA phase in addition to the nematic phase. The phase transitions viz., isotropic-nematic transitions studied in all these compounds were confirmed to be of first-order nature, whereas the N-SmA transition exhibited by the compound 5.O8O.5 only was found to be of second-order nature. We also report in this article the calculated density jumps, thermal expansion coefficient maxima, and pressure dependence of transition temperatures which are analyzed in the light of the available literature data.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据