Surface and thermodynamic studies of N-alkyl N-trimethylsilane ammonium chloride surfactants

N-Dodecyl N-trimethylsilane ammonium chloride, N-tetradecyl-N-trimethylsila ne ammonium chloride, N-hexadecyl-N-trimethylsilane ammonium chloride, and N-octadecyl-N-trimethylsilane ammonium chloride were prepared. Surface prop erties, particularly critical micelle concentration (CMC), effectiveness, m aximum surface excess, and minimal surface area, were determined at differe nt concentrations at 20, 35, 50, and 65 degrees C, respectively. From elect rical conductivity data, degrees of dissociation and dissociation constants at various concentrations were determined. Free energies, enthalpies, and entropies of micellization and adsorption of the surfactants in aqueous sol ution were studied.