STOCHASTIC DYNAMICS SIMULATION OF SURFACTANT SELF-ASSEMBLY

The self-assembly of short amphiphilic molecules of type A(2)B(2) (A=h ydraphilic, B=hydrophobic) is investigated using Stochastic Dynamics s imulations with a scalar frictional coefficient. Equilibrium propertie s were calculated and explained in the context of existing thermodynam ic theories. Spherical micelles are observed to form and the effect of temperature and total surfactant concentration on the structural prop erties are investigated. Above the critical micelle concentration, a d ecline in the free surfactant concentration is observed, contrary to e xisting theories dealing with micelle formation. The observed behavior can be explained in terms of excluded volume effects. Excellent agree ment is obtained between the resulting predictions and the simulation results over the entire concentration range. (C) 1997 American Institu te of Physics.