Anchev Borislav A, Tsekova Daniela S, Mircheva Kristina M, Grozev Nikolay A
Department of Organic Chemistry, University of Chemical Technology and Metallurgy St. Kliment Ohridski Boulevard 1756 Sofia Bulgaria
Department of Physical Chemistry, Faculty of Chemistry and Pharmacy, Sofia University St. Kliment Ohridski, 1 James Bourchier Boulevard Sofia 1164 Bulgaria.
RSC Adv. 2019 Oct 16;9(57):33071-33079. doi: 10.1039/c9ra06390k. eCollection 2019 Oct 15.
Herein, studies on the surface activities of newly synthesized l-Asp-based gemini surfactants, both nonionic and anionic, are presented. Conductometry, tensiometry, and the Langmuir-Blodgett (LB) film technique were applied for this purpose. - isotherms were obtained with a Langmuir trough and Wilhelmy balance. The structures of the monolayers assembled at the air/water interface and those deposited as LB films were studied Brewster angle microscopy (BAM) and atomic force microscopy (AFM). The 2D films formed by the anion-active compounds show a well-known pattern of a monolayer film, whereas the nonionogenic amphiphiles have been found to be 1D structures with nano-widths and micro-lengths that align with each other during the process of compression; this is the first study where the organization of 1D fibrils in 2D films during compression is reported. The scanning electron microscopy (SEM) study reveals that 1D nanostructure formation is an intrinsic tendency of these molecules as not only nonionogenic surfactants, but also the anion active representatives have been constructed in the solid state by fibrillary structures.
本文介绍了新合成的基于L-天冬氨酸的双子表面活性剂(包括非离子型和阴离子型)的表面活性研究。为此采用了电导法、表面张力测定法和朗缪尔-布洛杰特(LB)膜技术。用朗缪尔槽和威尔海姆天平获得了等温线。利用布鲁斯特角显微镜(BAM)和原子力显微镜(AFM)研究了在空气/水界面组装的单分子层结构以及作为LB膜沉积的结构。由阴离子活性化合物形成的二维膜呈现出众所周知的单分子层膜图案,而发现非离子型两亲物为具有纳米宽度和微米长度的一维结构,在压缩过程中它们相互排列;这是首次报道在压缩过程中二维膜中一维原纤维的组织情况。扫描电子显微镜(SEM)研究表明,一维纳米结构的形成是这些分子的固有趋势,因为不仅非离子型表面活性剂,而且阴离子活性代表物在固态下也由纤维状结构构成。