Surface Properties of Oils
Abstract
The surface properties of oils were studied in a short series of experiments upon their film viscosities and surface tensions. Information about film formation in general was obtained from the behavior of single bubbles upon the surface and from the coalescence of pairs of bubbles below the surface of various pure and binary liquids. The principal object of the investigation was to discover whether an excessive viscosity in the films was responsible for their stability. In the case of ordinary, only moderately stable, oil foams, this was found not to be the case, but in the case of certain modified oils adsorption at the air interface caused the formation of solid films responsible for stabilizing the foams. Foam inhibitors, on the other hand, left unchanged, or slightly decreased the film velocity. Another object of the study was to learn whether mixtures of hydrocarbons could of themselves form stable films or whether a surface-active "foaming agent" must be present. The time of coalescence of pairs of bubbles held below the surface of various liquids indicated that, while pure liquids could not form stable films, some of the binary mixtures thereof formed films of finite, although limited, stability. The inference is not excluded that the observed foaming ability of unmodified lubricating oils may be due partly to the mixture of hydrocarbons. Another object of the study was to determine whether foam stabilizers and foam inhibitors added to lubricating oils acted by their effect upon the surface tension. Such was not the case; in only one instance did an additive materially affect the surface tension, although the foaming was greatly changed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1949
- Accession Number
- ADA801551
Entities
People
- J. W. Mcbain
- James V. Robinson
Organizations
- Stanford University