| Abstract
| - A series of six surfactants, each with two ether oxygens within otherwise all-hydrocarbon chains, weresynthesized and examined for their colloidal properties. Since an ether oxygen is sterically andconformationally similar to the methylene group it has replaced, the ether effect on micellization shouldstem mainly from solvation of the oxygen and, possibly, disrupted hydrophobicity of its adjacent carbons.It was found that critical aggregation values among the surfactants differ only modestly despite the totallength of the ether-separated carbon segments ranging from 12 to 18. Shorter ether surfactants with only12 or 14 total carbons appear to form small, loose aggregates owing, presumably, to a mild hydrophilicityof the ether groups. A surfactant with 18 chain carbons has a greater tendency to associate hydrophobically,but this is counterbalanced by a relatively water-free environment encountered by the ether groups withina more conventional micelle interior. The result is a leveling effect in which the critical aggregationconcentration (cac) loses it sensitivity to chain length. Above their cac's, none of the ether surfactants isa good solubilizer of tetramethysilane or mesitylene. This is not necessarily a predictable finding sinceit was conceivable that the presence of interior ether groups might actually enhance solubilization (muchas ether is a better solvent than hexane). Foamability and solid adsorption studies also indicate that theethers impair surface activity. In response to the question posed in the paper's title, two ether groups arenot sufficiently hydrophilic to prevent aggregation, but they do manage to alter the micelles' morphologyand properties considerably.
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