Temperature-Jump Time-Resolved X-ray Diffraction Study of Cubic−Cubic Phase-Transition Kinetics in Thermotropic Cubic Mesogen 1,2-Bis(4′-n-alkoxybenzoyl)hydrazines (BABH-n)

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• 作者：Hiroyuki Mori ; Shoichi Kutsumizu ; Kazuya Saito ; Katsuhiro Yamamoto ; Shinichi Sakurai ; Koichi Sakajiri
• 刊名：Langmuir
• 出版年：2010
• 出版时间：July 20, 2010
• 年：2010
• 卷：26
• 期：14
• 页码：11605-11608
• 全文大小：749K
• 年卷期：v.26,no.14(July 20, 2010)
• ISSN：1520-5827

文摘

The transformation between two thermotropic bicontinuous cubic (Cub) phases has kinetically been determined by time-resolved X-ray diffraction. The system investigated was 1,2-bis(4′-n-alkoxybenzoyl)hydrazines (denoted as BABH-n, where n is the number of carbon atoms in the alkyl chain). Transitions from the Ia3d to Im3m phases of BABH-13 and from the Im3m to Ia3d phases of BABH-16 were induced by a temperature jump. Although the two Cub phases have quite different aggregation structures, the transitions between them appeared to occur without any diffractive intermediate states. A clear increase in the rate of transformation was observed upon increasing the extent of superheating, and the rate was slower than that reported previously for lyotropic systems. In addition, a comparison between the two transformations revealed that the rate of the Im3m to Ia3d transformation (of BABH-16) is ca. 5 times faster than that of Ia3d to Im3m (of BABH-13).