Showing papers on "Aggregation number published in 1971"
65 citations
01 Apr 1971
TL;DR: In this article, the micellar weight of dialkylsulfosuccinates, dialkyldimethylammonium halides, and polyoxyethylene 2(1,3-dioctoxypropyl) ether in nonaqueous solutions was measured by the vapor pressure depression method.
Abstract: The micellar weight of dialkylsulfosuccinates, dialkyldimethylammonium halides, and polyoxyethylene 2(1,3-dioctoxypropyl) ether in nonaqueous solutions was measured by the vapor pressure depression method The apparent aggregation number of anionic surfactants approached saturation values above a fixed range of concentration, whereas that of cationic surfactants generally increased with increase of concentration However, the nonionic surfactant formed no micelles in various solvents The aggregation number (λ) of both anionic and cationic surfactants generally decreased with increase in the total carbon number of the alkyl group The aggregation number of the anionic surfactant having the less bulky hydrocarbon group was larger than that of the anionic surfactant having the more bulky hydrocarbon group The order of magnitude of λ of surfactants having hydrocarbon groups of equal size was anionics⪢ cationics > nonionics in various solvents These results were compared with the results reported by other authors
60 citations
TL;DR: It was demonstrated that the sodium fusidate molecule, like a bile salt molecule, lies with its longitudinal axis horizontal at an air-water interface and is slightly larger than the corresponding aggregation numbers of sodium taurocholate micelles.
44 citations
TL;DR: Aggregation numbers of decyldiethylammonium, decylpiperidinium bromide and decylmethylmorpholinium (morphoBromide) were determined in 05 m NaBr and in 05m NaCl in this paper.
29 citations
TL;DR: Interfacial tension data and ultracentrifugal studies of solutions of the cyclic polypeptide alamethicin indicate that some form of micellisation takes place in aqueous solvents at very low concentrations.
29 citations
TL;DR: In this paper, the aggregation of four anionic azo dyes has been studied spectrophotometrically at high aqueous concentrations, using a cell of very small path length.
Abstract: The aggregation of four anionic azo dyes has been studied spectrophotometrically at high aqueous concentrations, using a cell of very small path length. The dyes all show apparent deviations from Beer's law and, using narrow particle size fractions of an azo pigment, apparent deviations from the law occur only when the particle size distribution of the absorbing species changes with concentration. On the basis of the stacking of the individual dye molecules behind one another to form aggregates, a theory has been developed relating the apparent deviation from Beer's law to the degree of aggregation, and average molecular weights have been evaluated for the four dyes.
27 citations
TL;DR: The ultraviolet absorption band of o-cresol was found to shift significantly when lysolecithin micelles were present in the aqueous solution, and this effect was utilized for the determination of the critical micelle concentration of lysoleCithin using a difference-spectroscopy technique.
24 citations
01 Oct 1971
TL;DR: In this paper, the critical micelle concentrations of four anionic surfactants were determined by DC polarographic desorption waves of the surfactant without supporting electrolyte.
Abstract: Critical micelle concentrations of four anionic surfactants were determined by DC polarographic desorption waves of the surfactants without supporting electrolyte. The linear plot obtained between the potentials of the desorption waves and the logarithmic concentrations of the surfactant had an inflection point which corresponded to the CMC. The CMC values obtained are in good agreement with those in the literature.
12 citations
01 Nov 1971
4 citations