Accession Number : AD0658058

Title :   SURFACE POTENTIALS OF ADSORBED ORGANIC MONOLAYERS ON METALS.

Descriptive Note : Technical rept.,

Corporate Author : ARMY WEAPONS COMMAND ROCK ISLAND ILL RESEARCH AND ENGINEERING DIV

Personal Author(s) : Martin,Peter , Jr

Report Date : JUL 1967

Pagination or Media Count : 22

Abstract : Surface potential measurements were accomplished to determine the effects of adsorbed organic monolayers on metal substrates. This data was used to characterize the monolayers as to their orientation, packing and polarization on metals. The vibrating condenser method was used to make surface potential measurements. The method is based on the principle of changing the capacity of a condenser formed by a reference electrode (Pt) and the metal to be studied. Any changes occurring on the metal will be detected by a potential change. Results obtained in this study were that (a) monolayers of acids, alcohols and amines absorbed on chrome cause an increase in the surface potential with an increase in carbon chain length; (b) oil solutions containing additives gave surface potentials in the order: octadecylamine > stearamide > stearic acid > octadecanol, and (c) temperature of wetting curves for the amines and amides correlated with surface potential curves. Conclusions derived were that (a) when alcohols, acids and amines of a sufficient chain length are adsorbed on chrome they form a close-packed oriented monolayer; (b) the tendency of adsorption from an oil solution onto steel depends on the type of additive used; and (c) amides with carbon chain lengths less than 16 have a higher energy of adsorption than the corresponding amines. (Author)

Descriptors :   (*ORGANIC COATINGS, *MONOMOLECULAR FILMS), (*LUBRICANTS, SURFACE PROPERTIES), (*ANTIOXIDANTS, SURFACE PROPERTIES), ADSORPTION, METALS, ELECTROCHEMISTRY, CHROMIUM, CARBOXYLIC ACIDS, AMINES, AMIDES, FATTY ACIDS, OILS, STEEL

Subject Categories : Physical Chemistry
      Miscellaneous Materials
      Lubricants and Hydraulic Fluids

Distribution Statement : APPROVED FOR PUBLIC RELEASE