N-甲基-N-十六烷基溴化物在水中的自组装行为研究(英文)

Self-Assembly Behavior of N-Methly-N-Hexadecylpiperidinium Bromide in Water

设计合成了非芳香类杂环离子液体N-甲基-N-十六烷基溴化物,并研究该离子液体在水中的自组装行为和液晶结构。该离子液体/水二元体系表现出双向溶致型六角相液晶,液晶范围和外观与离子液体浓度、温度相关。随着浓度增加,离子液体/水二元体系外观由澄清溶液变为透明溶胶,最后变为白色凝胶。溶致液晶在离子液体浓度范围30%~60%、升温过程中温度范围0.5~9.2℃、降温过程中4.8~19.8℃形成。与咪唑类离子液体在水中形成的液晶相比,饱和杂环离子液体分子由于缺少芳香环重叠效应,端头基重叠作用力减弱,使得饱和杂环离子液体分子在水中以较松散的方式组装。

N-methyl-N-hexadecylpiperidinium bromide was synthesized for the design of ionic liquid crystals based on saturated aliphatic heterocycles.The IL in water exhibits bidirectional hexagonal phase crystalline.The liquid crystalline range and appearance show concentration and temperature dependence.The appearance was observed to exhibit apparent solution,apparent sol and white gel with increasing the IL content.Over a content ratio of 30% to 60%,lyotropic liquid crystalline phase forms between 0.5 to 9.2 ℃ in the heating run and between 4.8 ℃ to-19.8 ℃ in the cooling run.The saturated aliphatic ionic liquid in water assemble less tightly compared with aromatic ionic liquid based on imidazolium in water,which is due to the absence of aromatic package effect.