Accession Number:

AD0646995

Title:

SPREADING PRESSURE, INTERFACIAL TENSION, AND ADHESIONAL ENERGY OF THE LOWER ALKANES, ALKENES, AND ALKYL BENZENES ON WATER,

Descriptive Note:

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON D C

Report Date:

1967-01-19

Pagination or Media Count:

30.0

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

Subject Categories:

  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE