Octadecyldimethylamine oxide

Monolayer Properties of Octadecyldimethylamine Oxide and Sodium Alkyl Sulfate... 

Monolayer properties of octadecyldimethylamine oxide alone and in combination wth sodium alkyl sulfate on aqueous substrate have been investigated. Nonionised amine oxide produces more expanded film than the ionised species minimum film expansion and highest surface potential are obtained at half ionisation. 

In the present study, the monolayer technique is used to investigate the surface properties of octadecyldimethylamine oxide and sodium octadecyl sulfate, as single component films and in combination. The interpretation of the results provides a direct understanding of the mechanism of interaction between these two surface active agents. 

Octadecyldimethylamine oxide (CieDAO) was a commercial sample from Onyx Chemical Company, Jersey City, N. J. (25% active). After evaporating the solvent in a rotary evaporator under reduced pressure, the crude product was recrystallised several times from ethyl acetate. The final product was dried and stored in vacuo over P2O5. Sodium octadecyl sulfate (SODS) was a sample prepared in this laboratory previously, and was recrystallised from ethanol before use. Sodium dodecyl sulfate (SDS) was obtained from Aldrich Chemical Company, and was of 98% purity. It was further purified by repeated crystallisation from ethanol followed by ether extraction. Benzene and methanol were gold-label reagent grade, purchased from Aldrich Chemical Company (Metuchen, N. J.). 

Tertiary amine oxides, such as octadecyldimethylamine oxide, have been found to act as PT catalysts under solid-liquid conditions, with the reaction between potassium acetate and benzyl chloride as the test. The sequence of Scheme 39 is suggested to generate a tetra-alkylammonium ion as the catalytic species. Polymeric amine oxides, e.g. (81), exhibit TC activity in the liquid-solid-liquid mode as demonstrated in the reaction of 1-bromo-octane with aqueous sodium cyanide. ... 

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