30951-88-3Relevant articles and documents
Synthesis and Physicochemical Properties of Double-Chain Cationic Surfactants
Engin ?zdil, Sinem,Akba?, Halide,Boz, Mesut
, p. 142 - 150 (2016/02/03)
In this study two types cationic surfactants were synthesized, purified, and characterized in our laboratory. One them is a series of cationic surfactants, a two tail-one head surfactant, N,N-dialkyl-N,N-diethylammonium bromide, abbreviated as "m-0-m" (m = 10, 12, and 16). The other type is N,N′-dialkyl-N,N,N′,N′-tetramethyl-N,N′-ethanediyl-diammonium dibromide, two tail-two head surfactants, abbreviated as "m-2-m" (m = 12 and 16). Once NMR spectra (1H NMR, 13C NMR) for all the gemini surfactants that were synthesized were taken, then the melting temperatures (TM) were measured. These surfactants have very high surface activity. The main goal of our study was to examine some properties of these two tail cationic surfactants by manipulating their dimeric structure. The effects of alkyl chain length and headgroup on surfactant self-assembly in solution were investigated. Critical micelle concentrations (CMC), degree of micelle ionization (α), and Krafft temperatures (TK) of 1 wt % aqueous solutions of these surfactants were determined by conductance measurements. Krafft points were found to be dependent on the number of carbon atoms in the alkyl chain and decreased by the addition of the electrolytes. The absence of the spacer group, peculiar to these twin tail cationic surfactants, may confer relatively low flexibility to the molecules, with potential implications on the interfacial properties, namely, on micellization.
Surface tension and aggregation properties of novel cationic gemini surfactants with diethylammonium headgroups and a diamido spacer
Zhang, Qi,Gao, Zhinong,Xu, Feng,Tai, Shuxin,Liu, Xueguo,Mo, Shaobo,Niu, Fei
, p. 11979 - 11987 (2012/11/07)
A series of novel cationic gemini surfactants with diethylammonium headgroups and a diamido spacer were synthesized, and their surface and bulk properties were investigated by surface tension, electrical conductivity, fluorescence, viscosity, dynamic light scattering (DLS), and transmission electron microscopy (TEM) measurements. An interesting phenomenon, that is, the obvious decline in surface tension upon increasing concentration above the critical micelle concentration (cmc), was found in these gemini surfactant solutions, and two explanations were proposed. This surface tension behavior could be explained by the rapid increase in the counterion activity in the bulk phase or the continued filling of the interface with increasing surfactant concentration above the cmc. More interestingly, not only vesicles but also the surfactant-concentration-induced vesicle to larger aggregate (spongelike aggregate) transition and the salt-induced vesicle and spongelike aggregate to micelle transition were found in the aqueous solutions of these gemini surfactants. The spongelike aggregate that is first reported in the cationic gemini surfactant-water binary system is probably caused by the adhesion and fusion of vesicles at high surfactant concentration.