单分子链胶束的胶束化行为与相关新概念的提出  

Micellization Behaviour of Unimolecular Micelles and Putting Forward of Correlative New Concept

作　　者：刘慷慨[1] 李蕾[1] 高保娇[1] 

机构地区：[1]中北大学化学工程系,山西太原030051

出　　处：《化学研究》2008年第1期83-89,共7页Chemical Research

基　　金：山西省自然科学基金资助项目(94012)

摘　　要：采用水溶液均聚合方法,制备了阳离子型表面活性单体(2-丙烯酰胺基)乙基十四烷基二甲基溴化铵(AMC14AB)的均聚物,使用荧光探针法、表面张力测定及电导测定法,重点考察了均聚物P(AMC14AB)在水溶液中的胶束化行为与表面吸附现象.在水溶液中,均聚物P(AMC14AB)呈现单分子链胶束的聚集形态,具有零临界胶束浓度(CMC=0),从开始加入P(AMC14AB)起,水溶液中随即产生单分子链胶束,不存在Krafft温度.P(AMC14AB)在溶液表面也发生表面吸附,使水的表面张力下降,即P(AMC14AB)也具有表面活性;随着浓度增大,表面吸附量增大,水的表面张力持续下降;当表面吸附达到饱和时,表面张力-浓度曲线上出现突变点,该点应该定义为饱和的表面吸附浓度(SSAC),而不应该再称为临界胶束浓度.P(AMC14AB)单分子链胶束溶液对疏水有机物(甲苯)的增溶情况,明显不同于普通小分子表面活性剂十六烷基二甲基溴化铵(CTAB)的多分子胶束溶液,甲苯增溶量-P(AMC14AB)浓度的关系曲线上无突变点,而且对甲苯的增溶能力高于CTAB的多分子胶束溶液.The Homopolymer of a cationic surface-active monomer, （2-acrylamido） ethyl tetradecyl dimethylammonium bromide （AMC14AB）, was prepared through aqueous solution polymerization, and the homopolymer P（AMC14AB） was obtained. The micellization behaviour in aqueous solution and surface adsorption on solution surface for P（ AMC14AB） were mainly examined by using fluorescence probe method, surface tension measurement and conductometry. In aqueous solution, homopolymer P（AMC14 AB） exists as monomolecular micelles and has zero critical micellar concentration （CMC = 0）, and once P（AMC14AB） is added into water, monomolecular micelles form immediately. There is no Krafft temperature for P（AMC14AB）. The adsorption phenomenon of P（AMC14AB） on solution surface also takes place, and leads to the decrease of surface tension. In the beginning, the surface adsorption amount of P（AMC14AB） increases and the surface tension decreases continuously with the increase of concentration. When the surface adsorption gets up to saturation, a turning point will appear on the curve of surface tension vs concentration. This point should be termed as ＂saturated surface adsorption concentration＂, instead of critical micellar concentration. The solubilization of the monomolecular mi- celles for hydrophobic organic substances is different from multiple-molecule micelles of common surfactants, and there is no mutational site on the curve of the solubilization amount of toluene vs P（AMC14AB） concentration. Moreover, the ability to solubilize toluene for the monomolecular micelles solution of P（AMC14AB） is higher than that of the multiple-molecule micelles solution of common surfactant cetyl trimethyl ammonium bromide（ CTAB）.

关 键 词：单分子链胶束 零临界胶束浓度 表面饱和吸附浓度 表面活性单体 (2-丙烯酰胺基)乙基十四烷基二甲基溴化铵 

分 类 号：O647.32[理学—物理化学]