MOLECULAR MODELING OF MICELLE FORMATION AND SOLUBILIZATION IN BLOCK-COPOLYMER MICELLES .1. A SELF-CONSISTENT MEAN-FIELD LATTICE THEORY

A self-consistent mean-field lattice theory used to model the solubilization of polycyclic aromatic hydrocarbons in poly(ethylene oxide)-poly(propylene oxide) block copolymer micelles is able to reproduce the experimental finding that the micelle-water partition coefficient of naphthalene increases with an increase in the poly(propylene oxide) content of the polymer and with polymer molecular weight. With the polycyclic aromatic hydrocarbons treated as flexible benzene chains, the model indicated a strong correlation between the micelle-water partition coefficient and the octanol-water partition coefficient of the solute, which was also observed experimentally. Linear, triblock copolymers and starlike, branched copolymers were studied. It was found that the linear polymers formed larger micelles with a more hydrophobic core environment, resulting in higher micelle-water partition coefficients.