Hexadecyl trimethylammonium chloride

Sheiham and Pinfold (81) have attempted to remove a cationic surfactant, hexadecyl-trimethylammonium chloride, by both solvent sublation and foam fractionation. A comparison (81) between the rates of surfactant removal by the two separation techniques shows that the separation of the cationic surfactant from 10 M solutions by solvent sublation into 2-octanol is slower but preferable if the foams are unstable. 

Functionalized micelles are increasingly being studied. An L-cysteine-functional-ized cationic micelle (27) is 1860-fold more effective than micelles of hexadecyl-trimethylammonium chloride in cleaving 4-nitrophenyl acetate. Acetylation of the thiol group occurs, followed by an intramolecular S- N transfer leaving the thiol group to cleave another molecule of the ester. ... 

The system studied in some detail consisted of an aqueous solution of hexadecyl trimethylammonium chloride (C Cl)-a gift from a private laboratory - purified three times by cr37stallization in methanol. This solution was carefully poured into a paraffin coated beaker containing a solution of Picric acid (HPi) - supplied by Merck - dissolved in nitrobenzene-chromatography grade supplied by UCB. The solvents were previously saturated by each other. The experiments were performed at 24°C 1. In this way, the only movements observed are those in the plane of the interface. Indeed the wettability of the wall involved in the three - dimen-... 

Figure 11.3. Determination of k and Kjn values from the linearity plots of aginst l/(Ct - CMC). A, hexadecyl trimethylammonium chloride B, hexadecyl trimethylam-monium bromide C, hexadecyl trimethylammonium nitrate. (Reproduced with permission of the Chemical Society of Japan.)...

A preliminary report (10) and a more detailed one (7) of the techniques employed are published elsewhere. Four cationic soaps are used as follows dodecyltrimethylammonium bromide (Ci2TABr,I) hexadecyl-trimethylammonium bromide H (Ci6TABr,II), hexadecylpyridinium chloride (Ci6PyCl,III), and hexadecyldimethylethylolammonium bromide (CioCholBr,IV). The last compound is related to choline bromide,... 

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. 

The preliminary treatment of the nanofiller to make it compatible is carried out with a substance having an affinity for both the montmorillonite and the chosen polymer, e.g., cetyl pyridinium chloride or bromide, hexadecyl trimethylammonium bromide, 7V-[4-(4 -aminophenyl)]phenyl phthalimide, /i-aminobenzoic acid hydrochloride, or a combination of octadecylamine hydrochloride and stearic acid. 

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