Orientation and lateral mobility of insoluble Tempo amphiphiles at the air/water interface
نویسندگان
چکیده
The lateral diffusion constants of two water insoluble redox surfactants, 4-alkaneamide derivatives of 2,2,6,6-tetramethyl-1-piperidynyloxy r a e
منابع مشابه
Electrochemical studies of the lateral diffusion of TEMPO in the aqueous liquid/vapor interfacial region.
Surface partitioning and lateral mobility of TEMPO (2,2,6,6-tetramethyl-1-piperidynyloxy free radical) in the aqueous liquid/gas interfacial region were investigated electrochemically with 100 nm wide, 1.0 cm long microband electrodes positioned at the air/water interface. For redox active amphiphiles such as TEMPO, the electrochemical current is the sum of the surface and solution components r...
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Two-dimensional electrochemical measurements were carried out with line microelectrodes positioned in the plane of the air/water interface to characterize the lateral mobilities of several long alkyl chain ferrocene amphiphiles possessing headgroups of different polarity. In the liquid range of mean molecular areas (MMA) of 55-95 Å2/molecule, the diffusion constants increase linearly with MMA. ...
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Surface partitioning of 2,2,6,6-tetramethyl-1-piperidynyloxy radical (Tempo) to the air/water interface follows a Langmuir isotherm. The partition constant was obtained by the surface tension measurements in the concentration range of 1.0 x 10(-4)-2.4 x 10(-3) M yielding K = 640 +/- 99 M(-1). The lateral mobility of Tempo at the air/water interface was measured electrochemically in the surface ...
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Monolayer films of a water-soluble surfactant, 4-octaneamido-2,2,6,6-tetramethyl-1-piperidinyloxy (C8-TEMPO) were investigated at the air/water interface. An electrochemical, horizontal touch method was developed to measure the equilibrium surface concentrations (gamma) of C8TEMPO. The dependence of gamma on the solution concentration followed a Langmuir isotherm and yielded the partition const...
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A new method is described to simultaneously determine the kinetics of surface partitioning and the lateral diffusion constant of redox active amphiphiles. It concerns water-soluble amphiphiles for which the surface adsorption equilibrium constant and the solution diffusion constant are measured independently. The method involves cyclic voltammetric experiments carried out at the air/water inter...
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