SPREADING PRESSURE, INTERFACIAL TENSION, AND ADHESIONAL ENERGY OF THE LOWER ALKANES, ALKENES, AND ALKYL BENZENES ON WATER,
Abstract
An investigation was made on the effect of molecular structure and unsaturation upon the initial spreading pressure (F sub ba) on water of numerous representative low-boiling hydrocarbons of exceptional purity. These compounds included members of the paraffin, olefin, aromatic, and acetylene families. Measurements of F sub ba were made at 20C using the 'piston monolayer' method. In agreement with the results of Washburn et al., F sub ba was always equal (or nearly so) to the initial spreading coefficient (S sub ba). The relations between the initial, semi-initial, final, and equilibrium spreading pressures and the corresponding spreading coefficients are discussed. The conditions under which the initial spreading pressure (F sub ba) is equal to the Harkins initial spreading coefficient (S sub ba) is established thermodynamically. It is shown that the value of S sub ba and the initial value of gamma sub ab, the interfacial tension against water, and W sub ba, the initial value of the reversible work of adhesion, can be calculated from F sub ba, the surface tension of the organic liquid (gamma sub b), and the surface tension of water (gamma sub a). Additional data on the hydrophilic nature of olefinic, aromatic, and acetylenic bonds are presented and discussed in terms of the molar work of adhesion. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 19, 1967
- Accession Number
- AD0646995
Entities
People
- Philip Pomerantz
- W. C. Clinton
- William A. Zisman
Organizations
- United States Naval Research Laboratory