Physicochemical Properties of Eicosane-1,20-bis(trimethylammonium) Dibromide in Aqueous Solution

Publisher Website
Google Scholar
Abstract
The physicochemical properties of a cationic α,ω-type(bolaform) surfactant, eicosane-1,20-bis(trimethylammonium) dibromide (C20Me6), were investigated by means of surface tension, electrical conductivity, density, dye solubilization, fluorescence, and light scattering. The results obtained for C20Me6 were compared with those for decyltrimethylammonium bromide (C10Me3). The surface tension measurement suggests that C20Me6 has a folded, “wicket-like” conformation at the air–water interface. The cmc of C20Me6 was smaller than that of C10Me3. The apparent ionization degree of C20Me6 was larger, and the polarity of the micellar Stern layer was higher than that of C10Me3. It was found that the C20Me6 micelle has an aggregation number of about 19, a hydrodynamic radius of 16 Å, and a partial molar volume of 480.49×10−3 dm3 mol−1, suggesting that the micelle is nearly spherical; thus, the main alkyl chain is almost stretched, and the outermost region of the micelle is loose.

This publication has 32 references indexed in Scilit: