Accession Number:

AD0685194

Title:

WETTING OF LOW-ENERGY SURFACES BY NONAQUEOUS SOLUTIONS OF DIMETHYL-SILOXANE-CONTAINING OR FLUOROCARBON-CONTAINING SURFACTANTS.

Descriptive Note:

Interim rept.,

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON D C

Report Date:

1969-02-27

Pagination or Media Count:

14.0

Abstract:

The wetting of low-energy solid surfaces by nonaqueous solutions has been investigated with solutions of copolymers of dimethylsiloxane-ethylene oxide and solutions of fluorocarbon-containing surfactants. The organic liquids studied were propylene carbonate, bis2-ethylhexylsebacate, isopropylbiphenyl, and a partially chlorinated biphenyl. Surface-tension-vs-concentration isotherms were determined for the surfactants in these liquids. The solid surfaces studied were stearic acid and 11-perfluorodecylundecanoic acid monolayers on stainless steel, polyethylene, and Teflon. In nearly all instances, the surfactants produced a marked improvement in the wetting of the low-energy surfaces by the organic liquids however, they did not cause spontaneous spreading of the organic liquids on the smooth, solid surfaces, even when when the solution surface tensions were depressed below the critical surface tensions of wetting of the solids. The failure of these surfactants to cause spontaneous wetting appears to be related to a the adsorption of the surfactant at the organic-solidair interface and b the failure of the surfactants to significantly reduce the organic-solidorganic-liquid interfacial tensions. Author

Subject Categories:

  • Physical Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE