Figure 6.

Schematic of Pluronic F127 micelles in the liquid crystalline phase (20% solution). The central, black region represents the approximate hard-core dimensions of the poly(propylene oxide) or (PO)₇₀ micelle core. The gray region represents the approximate hard-core dimensions of the poly(ethylene oxide) or (EO)₁₀₆ micelle brush if hypothetically flattened onto the core surface. White plus gray regions represent the dimensions of the hydrated (EO)₁₀₆ chains. Individual (EO)₁₀₆ chains (curly lines) will be more extended than an unperturbed random coil because of crowding near the micelle core surface. Dimensions of the interstitial region depend on the packing geometry and degree of extension of (EO)₁₀₆ chains into this region. Hard-core radii were calculated from the approximate molecular formula based on an aggregation number, n = 54 (24), and an assumed density of 1.0 g/cm³. The inter-micelle distance of 18 nm shown is based on small angle neutron diffraction studies (24).