Adsorption of block copolymers at liquid-liquid interfaces

In this study we employ scaling models developed for star polymers and copolymer micelles, where the dependence of monomer volume fraction on the radius is calculated using geometrical considerations. The free energy of the system is estimated and the relationship between interface curvature, surface density and system properties calculated. The results of the scaling model will be compared to self consistent field numerical calculations of the monomer density distribution and layer thickness of polymer chains adsorbed at curved interfaces. We consider the properties of a polymer layer of monodisperse AB diblock copolymer in a mixture of two highly selective and immiscible solvents. The two solvents are assumed to have equal excluded volume parameter for their respective blocks. We study two cases: that of a spherical interface and of a cylindrical one. It is assumed that all chains are aggregated at the interface, neglecting the possible presence of free chains in the bulk solvents. The copolymer is composed of N_A A segments and N_B B segments. It is assumed that N_A≥N_B, so that B block is assigned to the concave side, and A block to the convex (as depicted in Figure 1). It is also assumed that the interface is sharp.