Surface tensiometry

Edited by T. Kajiyama and M. Aizawa Vol. 5 Foam and Foam Films. By D. Exerowa and P.M. Kruglyakov Vol. 6 Drops and Bubbles in Interfacial Research. Edited by D. Mobius and R. Miller Vol. 7 Proteins at Liquid Interfaces. Edited by D. Mobius and R. Miller Vol. 8 Dynamic Surface Tensiometry in Medicine. By V.M. Kazakov, O.V. Sinyachenko,... 

V.N. Kazakov, O.V. Sinjachenko, V.B. Fainerman, U. Pison and R. Miller, Dynamic surface tensiometry in medicine, Studies in Interface Science, D. Mobius and R. Miller (Eds.), Vol. 8, Elsevier, Amsterdam, 2000... 

Details are given of the synthesis of nanosize PS particles by miniemnlsion polymerisation. The effect of varying the surfactant concentration on interfacial tension and colloidal stability was examined. Surface tensiometry was nsed to monitor the aqneons phase surfactant concentration via a calibration curve. TEM was used to confirm particle diameters and to measure the particle size distributions. 8 refs. 

The HT voltammetry with gold electrodes was also recently used to measure the surface partitioning constant of a soluble, redox-active surfactant at the air/water interface [25]. Malec and coworkers modified the surface of gold electrodes by self-assembly of short alkane chain thiols in order to mimic the thermodynamic properties of the air/water interface. They relied on the fact that the surface tensions of the air/water interface and of the liquid alkane/water interface are similar [8]. Indeed, the HT measurements of the Gibbs monolayer formation constant were in agreement with their surface tensiometry and Brewster angle microscopic measurements [25]. 

Contact angle measurements or surface tensiometry allow determination of surface energy or surface tension on polymer brushes (85). It also gives information on differences in morphology and fiinctional group distribution... 

Dynamic Surface Tensiometry in Medicine. By V.M. Kazakov, O.V. Sinyachenko,... 

Module 3) Synthesis and purification of biscationic gemini amphiphiles / H and C NMR characterization. Characterization of cmc using surface tensiometry, conductivity, fluorimetiy, and diffusion rate (DOSY NMR) (53)... 

Limitations on neutron beam time mean that only selected surfactants can be investigated by OFC-NR. However, parametric and molecular structure studies have been possible with the laboratory-based method maximum bubble pressure tensiometry (MBP). This method has been shown to be reliable for C > 1 mM.2 Details of the data analysis methods and limitations of this approach have been covered in the literature. Briefly, the monomer diffusion coefficient below the cmc, D, can be measured independently by pulsed-field gradient spin-echo NMR measurements. Next, y(t) is determined by MBP and converted to F(0 with the aid of an equilibrium equation of state determined from a combination of equilibrium surface tensiometry and neutron reflection. The values of r(f) are then fitted to a diffusion-controlled adsorption model with an effective diffusion coefficient which is sensitive to the dominant adsorption mechanism 1 for... 

Like surfactants, block copolymers form micelles above a critical concentration. The critical micelle concentration can be located by a variety of techniques [112], the most commonly used being surface tensiometry where the cmc is located as the point at which the surface tension becomes essentially independent of concentration. The primary methods to determine micelle size and shape are light scattering and small-angle X-ray and neutron scattering. The thermodynamic radius (from the thermodynamic volume, which is one eighth... 

Lake [117] used kinetic dialysis to examine the existence of cdc. The cdc of the sodium decanoate-sodium perfluorooctanoate mixed-micelle system was found to occur at a specific surfactant concentration and mole fraction. Ben Ghoulam et al. [118] determined the demixing diagram of the Neos Ftergent (a branched alkylbenzenesulfonate by surface tensiometry) and measured second critical micelle concentrations. However, a critical demicellization concentration was not observed. 

The lyotropic phases of the lithium and ammonium salts of perfluo-ropolyether (PFPE) carboxylic acids have been studied by optical microscopy [184], surface tensiometry, H-, and - C-NMR spectroscopy [179,184,185],... 

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