Octadecyltrimethylammonium chloride

By use of the Taylor dispersion method, diffusion coefficients for pyrene solubilized in micelles of octadecyltrimethylammonium chloride (CigTAC) and tetradecyltrimethyl-ammonium bromide (C14TAB) have been measur in aqueous NaCl and NaBr solutions, respectively, at 35 °C. These values can be regarded as tracer diffusion coefficients for the micelles b use essentially all pyrene molecules are solubilized in the micelles. In the range... 

In this study we have measured tracer diffusion coefficients of octadecyltrimethylammonium chloride (CigTAC) micelles in water and aqueous NaCl solutons at 35 °C. Due to its low critical micelle concentration (cmc), the smallest Ka value is as low as 0.18. We have also determined tracer diffusion coefficients for C14TAB micelles at 35 °C. 

Kamegawa and Yoshida (612] studied the pH dependence of the adsorption of several surface-active agents by chemically modified carbons. The uptake of nonionic polyoxyethylene nonylphenyl ether (PO) was not affected by pH, but it deereased with increasing outgassing temperature of the carbon. The uptakes of both the cationic octadecyltrimethylammonium chloride (OT) and the anionic sodium dodecylbenzenesulfonate (DB) exhibited a shallow minimum at intermediate pHs. The authors concluded that the van der Waals force was dominant in the adsorption of PO, while electrostatic attraction and repulsion, respectively, contributed to the behavior of OT and DB. 

Sorption colloid flotation has shown to be capable of quantitatively separating ionic mercury from sea water at levels down to 0.02 gg/1 using a cadmium sulfide collector and octadecyltrimethylammonium chloride as a surfactant. The sea water samples need only to be acidified with hydrochloric acid. For flotation an adjustment to pH 1.0 is crucial. Mercury concentrations generally seemed to decrease with the depth of sea water 99). 

Nonaystalfine Ti/Zr phosphates were also explored as catalysts for photochemical water splitting. The polymerization of titanium and zirconium tetraisopropanolates in aqueous H3PO4 in the presence of octadecyltrimethylammonium chloride produces a series of amorphous Ti/Zr phosphates, which after modification with Pt metal evolve H2 from water under UV fight.The activity increases with the Zr content to reach a maximum at a Ti/Zr molar ratio of 1 1. 

Octadecyltrimethylammonium chloride ( CaiHi,jNCl ) + Ethyl alcohol ( C HjO )... 

Octadecyltrimethylammonium chloride/bromide OTMAC/ OTMAB H3C N (CH2)i7CH3 CH3... 

As mentioned above, several types of PMO were synthesized using different templates and different reaction conditions. So, surfactant molecules are an important factor for the synthesis of PMOs and their numerous apphcations. The surfactants employed can be divided as shown in Figure 3.8. Ionic surfactants generally include C12-C18 alkyl chains with trimethylammonium head groups such as CTAB and octadecyltrimethylammonium chloride (OTAC). Nonionic surfactants consist of alkyl polyether type molecules such the Brij surfactants and the triblock copolymers such as Pluronic PI23 and FI27. 

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