Alkyl trimethylammonium bromide

The application of the activity of the surfactant has been examined also for the surface tension and adsorption of disodlum alkyl phosphate(6,7), sodium dodecyl sulfate(37), alkyl trimethylammonium bromide(35 ), and sodium perfluorooctanoate(13) solutions. These studies show that the surface tension and theadsorption amount are controlled by the activity of surfactant, irrespective of the added electrolyte concentration. 

Fig. 2.3. Plots of log CMC (in mole fraction units) versus nc, the number of carbon atoms in the alkyl chain. (Temperature in general 25 °C). a. Alkyl hexaoxyethylene glycol monoethers (Data from Ref.113)). b. Alkyl trimethylammonium bromides in 0.5 M NaBr (Data from Refs.28, 114)).

Neutron reflectometry has been applied to the study of a variety of surfaces, including solid polymeric films, ferromagnetic films, and pure liquid surfaces (Penfold and Thomas, 1990). The technique has also been used in conjunction with Langmuir film balance apparatus to study the adsorption of compounds at the air-water interface, e.g., alkyl trimethylammonium bromide surfactants (Lee et al., 1989), fatty acids (e.g., Grundy et al., 1988), and a variety of polymeric compounds (e.g., Henderson et al., 1991 Henderson, 1993). 

Figure 10. Differential molar enthalpies of displacement as a function of adsorption of alkyl-trimethylammonium bromides onto precipitated silica at 308 K.

R. Talhout, J. B. F. N. Engberts, Self-assembly in mixtures of sodium alkyl sulfates and alkyl trimethylammonium bromides aggregation behaviour and catalytic properties, Langmuir, 1997, 13, 5001-5006. 

FIGURE 4 Plots of In cmc versus hydrocarbon chain length at 25°C, unless otherwise stated A, alkyl hexaoxyethylene glycol monoethers B, alkyl sulfinyl alcohols C, alkyl glucosides D, alkyl trimethylammonium bromides in 0.5 M NaBr E, A/-alkyl betaines and F, alkyl sulfates in the absence of added salt at 40°C. [Composite from Tanford, C. (1980). The Hydrophobic Effect Formation of Micelles and Biological Membranes, Wiley, New York.]... 

Figure 3 shows the changes of cmc and a near the cmc for alkyl-trimethylammonium bromides of increasing chain length in water water + 1-18M propanol water + 0.5M butanol and water + 0.15M pentanol. The alcohol contents have been selected in order to have about the same value of a for TTAB in the three water-alcohol mix-... 

Taylor DJF, Thomas RK, Li PX, Penfold J (2003) Adsmption of oppositely charged poly-electrolyte/surfactant mixtures. Neutron reflectirai frran alkyl trimethylammonium bromides and sodium poly(styrenesulfonate) at the air/water interface the effect of surfactant chain length. Langmuir 19 3712... 

Bergeron, Langevin, and coworkers [52, 75, 76, 83-85] have made an extensive study of the spreading of PDMS oils on the surfaces of micellar surfactant solutions but have mainly confined their observations to two oils with respective molecular weights of 10 and 2.5 x 10 . Surfactants included AOT and homologues of alkyl trimethylammonium bromides. It is noteworthy that the spreading pressure of... 

Bergeron et al. [70] have also made a study of the mode of action of a PDMS oil-particle antifoam using micellar solutions of a variety of surfactants. The latter included AOT and some homologues of alkyl trimethylammonium bromides, the... 

Studies concerning the micelle formation/breakdown in mixed micellar solutions are few. Folger et al. showed that small amounts of STS (mole fraction 2-5%) significantly affected the value of T2 for SDS, particularly at C close to the cmc (see Figure 3.5). This is expected since micelle formation/breakdown is similar to a nucleation process. Patist et ai 160 reported that the slow relaxation process in solutions of SDS became considerably slower upon the addition of alkyl-trimethylammonium bromides. The largest effect was obtained with dodecyltrimethylammonium bromide, and the authors interpreted the results in terms of chain compatibility. Measurements of the slow relaxation time have been used to show that solutions of mixtures of some hydrocarbon and perfluorocarbon surfactants contain two types of mixed micelles, one rich in hydrocarbon surfactant, the other rich in perfluorocarbon surfactant. 

Sharma and Shah [46] reported that the surface tension of the SDS/alkyl alcohol aqueous solutions was minimum when the chain lengths of the surfactant and that of the alcohol were equal, e.g., for the SDS/CjzOH solutions. This was attributed to the tight packing of the molecules at the air-water interface. Patist et al. [47] reported similar results for SDS/alkyl trimethylammonium bromide/water systems. By the same token, C12 alkyl acrylates and methacrylate/SDS/water systems are expected to have a minimum surface tension and more solubilization of the monomer resulting in an increase in the one-phase region. The role of acrylates as cosurfactants has already been established in the case of hydroxy alkyl methacrylates [48]. 

Ethoxylated methylcarboxylates Propoxyethoxy glyceryl sulfonate Alkylpropoxyethoxy sulfate as surfactant, xanthan, and a copolymer of acrylamide and sodium 2-acrylamido-2-methylpropane sulfonate Carboxymethylated ethoxylated surfactants (CME) Polyethylene oxide (PEG) as a sacrificial adsorbate Polyethylene glycols, propoxylated/ethoxylated alkyl sulfates Mixtures of sulfonates and nonionic alcohols Combination of lignosulfonates and fatty amines Alkyl xylene sulfonates, polyethoxylated alkyl phenols, octaethylene glycol mono n-decyl ether, and tetradecyl trimethyl ammonium chloride Anionic sodium dodecyl sulfate (SDS), cationic tetradecyl trimethyl ammonium chloride (TTAC), nonionic pentadecylethoxylated nonylphenol (NP-15), and nonionic octaethylene glycol N-dodecyl ether Dimethylalkylamine oxides as cosurfactants and viscosifiers (N-Dodecyl)trimethylammonium bromide Petrochemical sulfonate and propane sulfonate of an ethoxylated alcohol or phenol Petrochemical sulfonate and a-olefin sulfonate... 

Currently available BAS include cholestyramine, colestipol and colesevelam hydrochloride (colestimide). Cholestyramine comprises a long-chain polymer of styrene with divinylbenzene trimethylbenzylammonium groups, whereas colestipol is a long-chain polymer of l-chloro-2,3-epoxypropane with diethylenetriamine. Colesevelam HCl is poly(allylamine hydrochloride) cross-linked with epichlorohydrin and alkylated with 1-bromodecane and 6-bromo-hexyl-trimethylammonium bromide. Bile-acid binding is enhanced and stabilised in the latter compound by long hydrophobic sidechains, increased density of primary amines, and quaternary amine sidechains. For this reason, colesevelam HCl exhibits increased affinity, specificity and capacity to bind bile acids compared with the other BAS. Colesevelam HCl also binds dihydroxy and trihydroxy bile acids with equal affinity, contrasting with cholestyramine and colestipol that preferentially bind dihydroxy bile acids (CDCA and deoxycholic acid). The latter BAS can lead to an imbalance towards trihydroxy bile acids and a more hydrophilic bile-acid pool. 

Fig. 12.47. Corrosion inhibition by n-alkyl-triethyl- and -trimethylammonium bromides in 1 W-H2S04 at 20 °C. (Reprinted from W. P. Singh, Relationships between the Structure of organic Compounds and Corrosion Inhibition, in Green Inhibitor Consortium, Texas A M University, 1997.)...

For most electrophoretic separations of small ions, the smallest analysis time results when the analyte ions move in the same direction as the electroosmotic flow. Thus, for cation separations, the walls of the capillary are untreated, and the electroosmotic flow and the cation movement are toward the cathode. For the separation of anions, however, the electroosmotic flow is usually reversed by treating the walls of the capillary with an alkyl ammonium salt, such as cetyl trimethylammonium bromide. The positively charged ammonium ions become attached to the negatively charged silica surface and in turn create a negatively charged double layer of solution, which is attracted toward the anode, reversing the electroosmotic flow. 

Reactions not fitting in with Section IV,F are listed in Table 15 cf. Scheme 43). Additionally it should be noted that S-alkylation of 2-mercapto TPs (such as 170) by benzylhalides gives higher yields and purer products when proceeding as a phase transfer reaction in ether-aqueous sodium hydroxide in the presence of benzyl-trimethylammonium bromide (04MI9). TP 170 and a,a -dichloroacetone react to yield a symmetrical bis-thioether (04MI3). 

The trimethylammonium surfactants were synthesized from the n-alkyl bromides and a double molar amount of a 40% aqueous trimethylammonium bromide solution. The mixture was diluted with ethanol, producing a 10% solution, and heated together for one hour at 60°C. The slightly yellow product was dissolved in ethanol and precipitated with diethyl ether. All other chemical reagents were of analytical quality from E. Merck (Darmstadt, FRG). 

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