A study of the properties and composition of stearic acid monolayers on an aqueous subphase containing cadmium ions

作者：Yanklovich M A; Ivanov N S; Sukhodolov N G; Zhukov A N^*

来源：Colloid Journal, 2016, 78(2): 277-280.

DOI：10.1134/S1061933X16020162

Compression isotherms and chemical compositions of stearic acid (HSt) monolayers applied onto an aqueous subphase containing cadmium ions have been studied in a wide pH range. The data obtained have been used to calculate the dependences of surface elasticity E (2.5), change Delta A (2.5) in the surface area per molecule at a constant two-dimensional pressure in the monolayer of 2.5 mN/m, and change Delta|zeta| in the absolute value of the zeta potential of particles formed from the material of a monolayer collapsed on the surfaces of aqueous solutions with the same compositions on the pH of the subphase. The obtained data are in good agreement with each other and unambiguously attest to the dependences of the surface (E (2.5), Delta A (2.5)) and electrosurface (Delta|zeta|) characteristics of the monolayers on their chemical composition. This leads us to make the reasonable suggestion that two alternative reactions may occur between cadmium ions and the HSt monolayer with the formation of two salts, CdSt(2) and Cd(OH)St.

• 出版日期2016-3