阳离子表面活性剂C_8NBr的溶致液晶体系研究

Study of lyotropic liquid crystal for cationic surfactant C_8NBr system

在25℃下,绘制了3-辛烷氧基-2-羟丙基三甲基溴化铵(C8NBr)/正丁醇/水体系的三元相图.用电导法确定了微乳液区域的变化过程.在液晶区域内选取一系列样品点,用偏光显微镜拍摄了相应的照片,研究了该体系的液晶结构特点.结果表明,随着含水量的增加,该体系的液晶变化为从层状→层状与六角状液晶共存→六角状→层状、六角状和立方状液晶共存→立方状液晶→层状向微乳液过渡.

Lyotropic liquid crystals formed in 3-octoxy-2-hydroxypropyl trimethyl bromide (C_8NBr)/n-buatnol/ water system were studied at 25℃.The variation in the microemulsion region was dtermined by conductivity method.It is found that the structure varies from W/O type through bicontinuous phase to O/W type microemulsion.Some typical photographs clearly showing texture of liquid crystal are obtained by using microscope with polarized-light.The specific region of liquid crystal are determined in the diagrams.The experimental results show that with the addition of water the phase structure varies from the single lamella liquid crystals through mixed lamella and hexagonal liquid crystals, to hexagonal, to mixed lamella,hexagonal and cubic crystals, to cubic crystal, to microemulsion.