N-Tetradecyltrimethylammonium bromide

Tarek et al. [388] studied a system with some similarities to the work of Bocker et al. described earlier—a monolayer of n-tetradecyltrimethylammonium bromide. They also used explicit representations of the water molecules in a slab orientation, with the mono-layer on either side, in a molecular dynamics simulation. Their goal was to model more disordered, liquid states, so they chose two larger molecular areas, 0.45 and 0.67 nm molecule Density profiles normal to the interface were calculated and compared to neutron reflectivity data, with good agreement reported. The hydrocarbon chains were seen as highly disordered, and the diffusion was seen at both areas, with a factor of about 2.5 increase from the smaller molecular area to the larger area. They report no evidence of a tendency for the chains to aggregate into ordered islands, so perhaps this work can be seen as a realistic computer simulation depiction of a monolayer in an LE state. 

Effects of addition of n-tetradecyltrimethylammonium bromide (C14TAB) on the micelle-monomer exchange processes of /f-decyltrimethylammonium bromide (CioTAB) were investigated by the ultrasonic relaxation method. The relaxation frequency increased and the relaxation strength decreased with increasing amount of CuTAB added. The dependence of the relaxation frequency on the amount of CuTAB added was in fair agreement with the relaxation theory of Annianson for mixed micelle... 

Abbreviations CTAB = hexadecyltrimethylammonium bromide SHDTE = sodium hexadecyl-trioxyethylene sulfate SDS = sodium dodecyl sulfate DTAB = dodecyltrimethylammonium bromide TTAB = tetradecyltrimethylammonium bromide bpy = 2,2 -bipyridyl MV- = N,N -dimethyl-4,4 -bipyridinium Rh = octadecylrhodamine DMA = A, .V-dimethylaniline. 

Course tuning selectivity Surfactant Choose surfactants of different selectivity (see Table 8.5) Sodium cholate (75 mM) Sodium N-Dodecanoyl-N-methyltaurine (50 mM) Tetradecyltrimethylammonium bromide (50 mM) with reverse polarity Other suitable surfactants ... 

FIGURE 6.14 Organic formulas of the following cationic hpids (1) benzaUconium chloride (alkyldimethylbenzylammonium chloride, BA) (2) cetrimide (tetradecyltrimethylammonium bromide, CTAB) (3) cetylpyridinium chloride (hexadecylpyridinium chloride, CPC) (4) dimethyldioctadecylammonium bromide (DDAB) (5) N,N-di-( 3-stearoylethyl)-N,N-dim-ethyl-ammonium chloride (Esterquat lEQ) (6) N-[l-(2,3-dioleoyloxy)propyl]-N,N,N-trime-thylammonium chloride (DOTAP). 

A number of molecular dynamics (MD) simulations of surfactant monolayers have been published during the last decade. In these studies, the water surface was often modelled as a flat, amorphous plane. Due to severe computer power restrictions, there have been only a few attempts in which the surface was modelled in all atomic details. Monolayers of trimethylammonium chloride at the air/water interface and the properties of tetradecyltrimethylammonium bromide monolayers have been simulated. In addition to these computer experiments, the structures of phenol, p-n-pentylphenol and A,V -diethyl-p-nitroaniline adsorbed on water have been investigated by MD simulations. Recently, molecular dynamics simulations of sodium dodecyl sulfate at the water/vapour and the water/CCU interfaces in regimes of small surface concentrations have been performed (4). 

Synertyms Ammonium, tetradecyltrimethyl-, bromide Ammonium, trimethyltet-radecyl-, bromide MTAB Myristyl trimethyl ammonium bromide Quatemium 13 1-Tetradecanaminium, N,N,N-trimethyl-, bromide Tetradecyltrimethylammonium bromide Tetradonium bromide Trimethylmyristylammonium bromide N,N,N-Tri-methyl-1-tetradecanaminium bromide Trimethyltetradecylammonium bromide HAB... 

Oxidation of terminal olefins to methyl ketones by aqueous palladium chloride and oxygen is very slow, but addition of micellar sodium lauryl sulphate increases the rate of formation of 2-octanone from 1-octene twentyfold at 50 °C. There is weaker catalysis by the non-ionic surfactant Brij-35 and inhibition by cationic surfactants. " Oxidation of diosphenol (35) in basic aqueous tetradecyltrimethylammonium chloride is faster and more effective than in water, giving a higher yield of (36). Two attempts at effecting the enantioselective reduction of aromatic ketones, one in micelles of R-dodecyl-dimethyl-a-phenylethylammonium bromide and the other in sodium cho-late micelles, both give optical yields of less than 2%. Rather more success was obtained in the catalysed oxidation of L-Dopa, 3,4-dihydroxyphenyI-alanine. In the presence of the Cu complex of N-lauroyl-L-histidine in cetyl-trimethylammonium bromide micelles reaction was 1.42 (pH 6.90, 30 °C) to... 

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