pH及有机小分子物质对SDS/CTAB/H2O系统双水相性质的影响

正离子表面活性剂与负离子表面活性剂混合物能产生比单一表面活性剂更高的表面活性1 ] 。在适当条件下 ,正负离子表面活性剂的水溶液能产生两个互不相溶的水相 ,即表面活性剂双水相系统2 ] (ＡｑｕｅｏｕｓＴｗｏ -ＰｈａｓｅＳｙｓｔｅｍ -ＡＴＰＳ)。作者曾指出双水相上相为液晶 (ＬｉｑｕｉｄＣｒｙｓｔａｌ -ＬＣ)结构 ,下相为各向同性溶液 ,盐离子通过改变双水相中表面活性剂有序组合体的反离子层的状态而对双水相的组成、结构等产生重要的影响3,4] 。本文进一步研究ｐＨ及有机小分子物质在十二烷基硫酸钠 /十六烷基三甲基溴化铵 /…

Influence of pH and small molecule organic compound on the aqueous two-phase system formed by SDS/CTAB/H2O mixture

This study was about the effect of pH and small molecule organic compound on the phase behavior of SDS/CTAB/H 2O mixture.The ATPS regions and LC regions were mainly discussed.It was shown that when the pH of the system was not neutral LC regions enlarged but ATPS regions reduced.In the condition of strong acid,the ATPS a region in which anionic surfactant in excess would extend to the SDS-H 2O axis of the pseudo phase diagram of SDS/CTAB/H 2O system.Small molecule organic compound that was not ionized in aqueous solution combined with water in the form of hydrogen bond.For this reason,the hydration of surfactant decrease and cationic surfactant and anionic surfactant integrate to form precipitate.So the surfactant-rich phase of ATPS showed milky white and the polarizing appearance was not clear.