Mesomorphic phase transitions of a series of D-phase compounds
Mesomorphic phase transitions of a series of D-phase compounds
复制标题
一系列 D 相化合物的介晶相变
DOI：
10.1080/02678299408027881
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发表时间：
1994
期刊：
影响因子：
2.2
通讯作者：
S. Yano
中科院分区：
文献类型：
--
作者：
S. Kutsumizu;M. Yamada;S. Yano
摘要 采用差示扫描量热法 (DSC) 和偏光光学显微镜研究了烷氧基碳数 (n) 为 11 至 22 的 4'-正烷氧基-3'-硝基联苯-4-羧酸 (ANBC) 的介晶相变。 D 相是一种特别令人感兴趣的中间相，因其光学各向同性，在 ANBC 的 n = 17、19、20、21 和 22 个成员以及 n = 16 和 18 个成员中观察到，如先前报道的。 Sc-D相变温度随着n的增加而降低，因此在n=22时D相的温度范围扩大了64°以上。在n=15的构件中，在第一次加热时确实观察到了D相，但在随后的冷却和第二次加热过程中没有观察到D相。
Abstract Mesomorphic phase transitions of 4′-n-alkoxy-3′-nitrobiphenyl-4-carboxylic acids (ANBC) with numbers of carbons (n) in the alkoxy group ranging from 11 to 22 have been studied by differential scanning calorimetry (DSC) and polarizing optical microscopy. The D phase, a mesophase of particular interest through its being optically isotropic, was observed for the n = 17, 19, 20, 21, and 22 members of the ANBCs, as well as for the n = 16 and 18 members, as reported previously. The Sc-D phase transition temperature decreased with increasing n, so that the temperature range of the D phase extended over 64° at n = 22. In the n = 15 member, the D phase was certainly observed on first heating, but was not seen on subsequent cooling and second heating processes.