CONTACT ANGLES AS INDICATORS OF MICELLIZATION

Wetting of low and high energy surfaces by aqueous solutions of ionic and nonionic micelle-forming surfactants was studied. For low energy s urfaces, a distinct correlation between the isotherms of contact angle s theta(C) and the surface tension sigma(LV)(C) of the solutions was o bserved, namely, a sharp inflection on the theta(C) isotherms correspo nded to known values of the critical micellization concentration (CMC) for all studied surfactants. For the wetting of high energy surfaces, the sessile drop method does not allow us to determine the CMC. Howev er, for anionic and nonionic surfactants, the CMC may be determined by the capillary rise method. In this case, a correlation between the is otherms of the height of capillary rise h(C) and sigma(LV)(C) isotherm s was revealed.