Connection between Solubility Parameter Theory and Lattice Theory and the Connection between Solubility Parameters and Interfacial Energies

We show using lattice theory and solution theory the fundamental connection between interfacial tensions and solubility parameters [as demonstrated by Murase and Nakamura (MN)], and the reason why they must be correlated, with certain limitations. This requires that the ratio of molecules' volume to their effective surface area of interaction be roughly a constant. This is the case for most molecular species whose size varies as linear chains or sheets, increasing the surface-area proportionally to volume. For molecules which interact via dispersion forces where the theory applies most rigorously, the constant roughly estimated to be ∼ <i>v</i>/<i>a</i> = 1 × 10^-8 cm is extremely close to the parameter obtained in MN's correlation. We show how this connects to local composition, both in the bulk and for preferential adsorption at interfaces.