应用原子力显微镜研究混合表面活性剂不溶膜的结构

Investigation on Structure of Mixed Monolayer by AFM

利用ＬＢ技术和原子力显微镜（ＡＦＭ）研究表面活性剂混合不溶膜的结构。结果表明Ｃ１８Ｈ３７ＳＯ３Ｎａ－Ｃ８Ｆ１７ＣＯＯＨ混合凝聚膜发生相分离，Ｃ１８Ｈ３７ＳＯ３Ｎａ形成六方微畴分布在连续的Ｃ８Ｆ１７ＣＯＯＨ相中；Ｃ１２Ｈ２３ＳＯ４Ｎａ－Ｃ１８Ｈ３７Ｎ（ＣＨ３）３Ｂｒ形成了相当均匀完整的混合膜；Ｃ１８Ｈ３７Ｎ（ＣＨ３）３Ｂｒ－Ｃ８Ｆ１７ＣＯＯＨ所成膜呈微不均匀状态。结果说明混合不溶膜表面状况由极性头相互作用与疏水基相互作用共同决定。

Mixed monolayers of surfactants were investigated by AFM and LB technique.Condensed monolayer of C 18 H 37 SO 3Na C 8F 17 COOH mixture shows two dimensional phase separation and crystallization.C 18 H 37 SO 3Na forms hexagonal domains dispersing in the continuous two dimensional phase of C 8F 17 COOH;C 12 H 23 SO 4Na C 18 H 37 N(CH 3) 3Br mixture forms a homogeneous mixed monolayer;while the mixed monolayer of C 18 H 37 N(CH 3) 3Br and C 8F 17 COOH mixture shows heterogeneous in microscope.Relations between structure and state of mixed monolayer to the interactions between their hydrophilic groups and that between their hydrophobic groups have been revealed.