Cetyltrimethyl ammonium chloride

A fascinating area is micellar autocatalysis reactions in which surfactant micelles catalyse the reaction by which the surfactant itself is synthesized. Thus synthesis of dimethyldoceylamino oxide (reaction between dimethyl dodecyl amine and H2O2) benefits from this strategy. Here an aqueous phase can be used and an organic solvent can be avoided. Synthesis of mesoporous molecular sieves benefit through micellar catalysis and silicate polymerization rates have been increased by a factor 2000 in the presence of cetyltrimethyl ammonium chloride (Rathman, 1996). 

Ito et al. [175] used this technique employing octadecyl silane reverse phase columns coated with cetyltrimethyl ammonium chloride for the determination of nitrite and nitrate in seawater. 

Catalysis B and D were obfained from a commercial plant for cafalysf production. The production methods were similar to catalyst C but more simple. Catalyst E was obtained in the same manner as catalyst A, except that cetylpyridinium chloride was replaced by cetyltrimethyl ammonium chloride. 

Figure 18. Excimer/monomer fluorescence intensity ratio 77/ at 30°C of l,3-di(l-pyrenyl)propane [Py(3)Py] as a function of the reciprocal viscosity for a series of hexadecane-liquid paraffin mixtures (curve). The 77/ ratios obtained with Py(3)Py in aqueous micellar solutions of sodium dodecyl sulfate (SDS, 0.1 Af), cetyltrimethyl-ammonium chloride (CTAC, O.OS Af), and Triton X-100 (0.004 Af), and in the microemulsion SHS(M) (see Table 7) are indicated. The fluidities determined were 3.1 mPa s (SHS(M)], 11 mPa s [SDS] 37 mPa s [CTAC], and 105 mPa s [Triton X-100]. Redrawn after Ref. 167.

Other inorganic nanoparticles have been encapsulated with miniemulsion polymerization, and a hydrophobilizing agent was used to render the particles hydrophobic prior to minianulsification. For example, calcium carbonate was pretreated with stearic acid prior to being dispersed into the monomer phase. Alumina and magnetite were pretreated with oleic acid, laponite was pretreated with a cetyltrimethylammonium bromide, and silica was pretreated with cetyltrimethyl-ammonium chloride" or methacryloxy(propyl)trimethoxysilane. ... 

Reagent A.R. aqueous ammonia, metal nitrates, benzene, commercial cetyltrimethyl ammonium chloride and kerosine. 

Characterization the thermal stability of cetyltrimethyl ammonium chloride was tested with a Du Pont 99 Thermal Analyzer. The morphology of the catalyst was examined by a HITACHI H-600 Electron Microscope. The surface area of the samples was measured with an ASAP200 of hficromeritics Co. 

Nanometer particle Cu0-Zn0/Al203 can be prepared by phase transfer with cationic surfactant cetyltrimethyl ammonium chloride. The product is stable at 400°C and can be calcined at 350°C for a long time. Cetyltrimethyl ammonium chloride possesses a universal suitability. 

A considerable advance is the application of surfactant analogues of methyl-viologen as the electron-acceptor. The dication (122) forms micelles above 7 X 10 M and does not have a particularly high affinity for cetyltrimethyl-ammonium chloride micelles. The monocationic reduced form is much less hydrophilic, however. A direct consequence is that the forward electron transfer is unaffected by cationic micelles... 

The rate constants of the phosphorescent probe s exit from cetyltrimethyl-ammonium chloride micelles were determined by Bolt and Turro [155]. The logarithm of the rate constant is a linear function of the number of the carbon atoms in the probe molecule. The apparent activation energy of the exit process is 9 kcal/mole. 

M.M. Yusuf et al. have reported mesoporous Ti02 films with controlled pore sizes prepared by smfactant templating sol-gel method and its photocatalytic activity. The porous films of anatase with rectangular and columnar structure were obtained by annealing after immersion of the wet gel films in benzyltrimethylammonium chloride- and cetyltrimethyl-ammonium chloride-solutions, respectively. They concluded that the microstructure of the sol-gel derived films can be controlled by changing the type of surfactant species and the concentration of surfactant solutions. The photocatalytic activity of their films for the oxidation of NO , was improved by the surfactant modification (Yusuf, 2002). 

The above cysteine-containing long hydrocarbon chain forms micelles between 0.003 and 0.05 M and cleaves p-nitrophenyl acetate with a pseudo-first-order rate constant. The surfactant is 180 times more reactive than cetyltrimethyl ammonium chloride, a micellar system without a functional group present. 

Anionics (C,2 AS, C12 LAS, dioctylsulfosucci-nate, C12 soap), nonionics (AE ),OPE, , NPE5), and cationics (cetyltri-methylammonium bromide, cetylpyridinium chloride, cetyltrimethyl-ammonium chloride) demonstration of 2-dimensional TLC with hybrid NP/RP plates... 

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