Alkyl propoxy ethoxylate "graded" surfactants: micelle formation and structure in aqueous solutions.
The self-assembly of alkyl propoxy ethoxylate surfactants in aqueous solutions has been investigated with a focus on the (i) thermodynamics of micellization (critical micellization concentration; free energy, enthalpy, and entropy of micellization) and (ii) structure of the micelles (overall shape and size; local environment in the micelle core and corona) as affected by the surfactant composition (variation of degree of ethoxylation). The various results are compared to those for alkyl ethoxylate and poly(ethylene oxide)-b-poly(propylene oxide) amphiphiles with the aim to elucidate the role of the middle, propoxy, block in the novel alkyl propoxy ethoxylate surfactants which exhibit a "graded" hydrophobic-hydrophilic character.
Sarkar
Biswajit
B
Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York (SUNY), Buffalo, New York 14260-4200, USA.
Alexandridis
Paschalis
P