Didodecyldimethylammonium bromid

Didodecyldimethylammonium bromide forms in the dilute-phase cylindrical reversed micelles in the range 2 < / < 8, showing an abrupt structural change at/ = 10 and forming spherical aggregates at/ > 10 [17],... 

The ITIES with an adsorbed monolayer of surfactant has been studied as a model system of the interface between microphases in a bicontinuous microemulsion [39]. This latter system has important applications in electrochemical synthesis and catalysis [88-92]. Quantitative measurements of the kinetics of electrochemical processes in microemulsions are difficult to perform directly, due to uncertainties in the area over which the organic and aqueous reactants contact. The SECM feedback mode allowed the rate of catalytic reduction of tra 5-l,2-dibromocyclohexane in benzonitrile by the Co(I) form of vitamin B12, generated electrochemically in an aqueous phase to be measured as a function of interfacial potential drop and adsorbed surfactants [39]. It was found that the reaction at the ITIES could not be interpreted as a simple second-order process. In the absence of surfactant at the ITIES the overall rate of the interfacial reaction was virtually independent of the potential drop across the interface and a similar rate constant was obtained when a cationic surfactant (didodecyldimethylammonium bromide) was adsorbed at the ITIES. In contrast a threefold decrease in the rate constant was observed when an anionic surfactant (dihexadecyl phosphate) was used. 

CTAB = cetyltrimethylammonium bromide DDAB = didodecyldimethylammonium bromide DEG = diethylene glycol DOE = dioctyl ether DPE = diphenyl ether DS = dodecyl sulfate EG — ethylene glycol EtOH = ethanol HAD = hexadecylamine HD = 1-hexadecene OD = 1-octadecene HDD = 1,2-hexadecanediol ... 

A microemulsion made from dodecane, water, and didodecyldimethylammonium bromide has proven to be a good medium for the catalytic reduction of trans-1,2-dibromocyclohexane and for Sn2 reactions... 

Kondo, Y., Uchiyama, H., Yoshino, N., Nishiyama, K., and Abe, M. (1995). Spontaneous vesicle formation from aqueous-solutions of didodecyldimethylammonium bromide and sodium dodecyl-sulfate mixtures. Langmuir, 11, 2380. ... 

Didodecyldimethylammonium bromide [3282-73-3] M 463.6. Recrystd from acetone, acetone/ether mixture, then from ethyl acetate, washed with ether and dried in a vacuum oven at 60° [Chen et al. JPC 88 1631 1984 Rupert et al. JACS 107 2628 1985 Halpem et al. JACS 108 3920 1986 Allen et al. JPC 91 2320 1987],... 

Materials. Sodium dodecylsulfate (SDS) and fully deuterated sodium dodecylsulfate (SDS-d ) were obtained from Sigma and Cambridge Isotope Laboratories respectively, and used as received. The cationic surfactants, dodecyltrimethylammonium chloride (DTAC), dodecyltrimethylammonium bromide (DTAB), and didodecyldimethylammonium bromide (DDAB) were purchased from Eastman Kodak, and purified by repeated recrystallization from an ethanol/acetone solvent pair. Even so, a small amount of surface active impurity was observed in surface tension plots for DTAC. The tetradecyldimethylamine oxide (C14AO) was a commercial sample (Ammonyx MO) obtained from Stepan (Control No. 533-30027). This sample is primarily C14AO, but also contains other chain length components. Sodium chloride (NaCl) was obtained from EM Science and used as received. Water was purified by a three stage Bamstead water purification system. 

Reversal of the direction of the EOF using the cationic surfactant didodecyldimethylammonium hydroxide (DDAOH) in reversed polarity mode has also been reported (16). The bromide form of this surfactant (DDAB (didodecyldimethylammonium bromide)) was converted to the hydroxide form to eliminate an undesirable system peak caused by bromide. Using 10 mM phenylphosphonic acid as the probe and a buffer consisting of 200 mM borate, 0.35 mM DDAOH, and 0.03% Trition X-100 at pH 4.0, the separation of 8 alkylphosphonates was achieved in less than 3 min. Eimits of detection were in the 100 xg/L range. 

Connolly, D. and Pauli, B. Fast ion chromatography of common inorganic anions on a short ODS column permanently coated with didodecyldimethylammonium bromide. J. Chromatogr A. 2002, 953, 299-303. 

Approximately 6 mu iron nanoparticles are formed if Fe(CO)s is thermally decomposed in the presence of oleic acid and TBP. Their structure is bcc, like that of bulk iron. 2mn Fe particles are generated if the decomposition of Fe(CO)s is performed in TOP at 320 340 °C. They can be used to form rod-shaped species of 11 27 mu length by heating in pyridine in the presence of didodecyldimethylammonium bromide. ... 

Figure 2. Ternary phase diagram of the system didodecyldimethylammonium bromide / water / hexene at 25°C. The nomenclature is cub cubic phase Lamj and Lam2 lamellar phases l.c. liquid crystalline, inverted hexagonal phase L2 microemulsion phase, with curvature toward water. (Courtesy of K. Fontell).

Average value obtained using 2,6-diphenyl-4-(2,4,6-triphenyl-l-pyridinio)phenoxide, 1-hexadecyl-4-[(oxocyclohexadienylidene)ethylidene]-l,4-dihydropyridine, l-hexadecyl-5-hydroxyquinoline and l-hexadecyl-6-hydroxyquinoline, average deviation <9 % calculated from [47d]. Abbreviations SDS = sodium dodecyl sulfate DBS = dodecyl benzenesulfonate CTAC = hexadecyltri-methylammonium chloride CTAB = hexadecyltrimethylammonium bromide DTAC = dodecyl-trimethylammonium chloride DTAB = dodecyltrimethylammonium bromide DHP = dihexadecyl phosphate DDDAB = didodecyldimethylammonium bromide DMPC = dimyristoylphosphati-dylcholine DPPC = dipalmitoylphosphatidylcholine POPC = l-palmitoyl-2-oleoylphosphati-dylcholine PCA = phosphatidic acid. 

Figure 12.25 Phase diagram of didodecyldimethylammonium bromide (DDAB) in water and styrene at 20°C. The phases include an oil-rich isotropic phase L2, lamellar phases, and five distinct cubic strut phases, including the G, D, P, C(P), and an unknown phase C5. Above the cubic phases are regions of two- and three-phase coexistence. (From Strom and Anderson 1992, reprinted with permission from Langmuir 8 691. Copyright 1992, American Chemical Society.)...

Very few rheological data have been reported for ordered cubic phases of surfactant solutions. However, Radiman et al. (1994) have reported dynamic oscillatory data for solutions of didodecyldimethylammonium bromide (DDAB) in deuterated water and octane. Their data for type II cubic P and D phases are shown in Fig. 12-29. They report that the samples... 

Figure 12.29 Frequency-dependence of G ( ), G ( ), and rj (Q) for (a) the P phase and (b) the D phase of a mixture of didodecyldimethylammonium bromide (DDAB) in D2O and octane. (Reprinted with permission from Radiman et al., Langmuir 10 61. Copyright 1994, American Chemical Society.)...

Figure 4.2 a) The formation of a didodecyldimethylammonium bromide (DODAB) vesicle by sonication of planar bilayers (BLM). 

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