A homologous series of new gemini cationic surfactants were synthesized and characterized using micro elemental analysis, FTIR, 1 H-NMR and mass spectra. The surface activities of these amphiphiles were determined based on the data of surface tension. Critical micelle concentration, effectiveness of the surface tension reduction, efficiency of adsorption, maximum surface excess, minimum surface area and critical packing parameter were evaluated. The effect of cationic micelles on solubilization of anionic azo dye, sulforhodamine B (Acid Red 52) in aqueous micellar solution of the synthesized gemini cationic surfactants was studied at pH 6.9 ± 0.5 and 25°C. The results showed that the solubility of dye rose with increasing surfactant concentration as a consequence of some association between the dye and the micelles. It was also observed that the aggregation of surfactant and dye takes place at a surfactant concentration below the CMC of the individual surfactant. The partition coefficients between the bulk water and surfactant micelles as well as the Gibbs energies of distribution of dye between the bulk water and surfactant micelles were calculated using a pseudo-phase model. The effect of the hydrophobic chain length of Gemini cationic surfactants on the distribution parameters was also reported. The results show favorable solubilization of dye in cationic micelles.

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A novel series of anionic Schiff base amphiphiles were synthesized. The chemical structures of these compounds were elucidated using different spectroscopic tools. The surface and thermodynamic properties of the prepared Schiff bases were studied using classical measurements including surface and interfacial tensions. The surface parameters of these compounds, e.g., surface tension, critical micelle concentration, effectiveness, efficiency, maximum surface excess, minimum surface area, and interfacial activity showed their good surface activity. Their thermodynamic parameters of adsorption and micellization including free energy change of micellization and adsorption showed their tendency toward adsorption at the interfaces and also micelle formation at lower concentrations. The complexation behavior of the synthesized Schiff bases were study through the interaction of the Schiff base (IIIa; SBSD) with nickel chloride hexahydrate. All synthesized compounds in addition to NiCl 2 Á6H 2 O and Ni Schiff Base complex have been evaluated for their antibacterial activity against Gram-positive and Gram-negative bacteria. The results of the biocidal activities showed high potent action of (Ni-III a ; Ni-SBSD) complex more than Schiff base IIIa; SBSD.

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A series of Gemini borate surfactants were synthesized based on glucose molecule. Their chemical structures were confirmed using 1 H-NMR, 13 CNMR and mass spectroscopy.The surface activities of these Gemini amphiphiles were measured, including surface tension (γ), critical micelle concentration (cmc), effectiveness (П cmc ), efficiency (pC 20 ), maximum surface excess (Γ max ) and minimum surface area (A min ) at different temperatures 25, 35 and 45°C either in pure water or in water-ethanol mixture (10%).Also, thermodynamic data including, free energy, entropy and enthalpy changes (ΔS,TΔS,ΔH) for adsorption at the air-water interface and also for micellization in Downloaded by [New York University] at 02:22 01 August 2015 2 surfactant solutions were calculated.