Physicochemical Properties Of Noncovalently Constructed Sugar Based Pseudogemini Surfactants: Evaluation Of Linker Length Influence

Natural renewable glucose or lactose upon reaction with dodecylamine has been converted into N-dodecylglucosylamine or N-dodecyllactosylamine, which upon acid-alkali reaction with dicarboxylic acid (HOOC(CH2)(n-2)COOH, n = 3,4,5,6,8) gives a series of sugar-based pseudogemini surfactants (G-n, L-n, respectively). Some physicochemical properties such as the critical micelle concentration (CMC), equilibrium surface tension at the CMC (gamma(CMC)), effectiveness (pi(CMC)), efficiency (pC(20)), maximum surface excess (Gamma(max), minimum surface area (A(min)), counterion binding of micelles (beta), and the changes of standard Gibbs free energy (Delta G(m)(0), enthalpy (Delta H-m(0)) and entropy (Delta S-m(0)) for processes of micellization in the range 298.15 K to 328.15 K have been evaluated by surface tension and electroconductometry methods in aqueous solutions of these pseudogemini surfactants. The results revealed that most of the above properties depend on dicarboxylic acid linker length and headgroup saccharide size. These findings help with understanding the structure-properties relationships of surfactants so as to construct new pseudogemini surfactants.