Formation and Dynamics of Self-Organized Structures in Complex Fluids

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In this research, we applied the self-consistent field (SCF) theory, which is a useful tool in theoretical predictions of the spatially inhomogeneous structures in dense polymer systems, to various practical problems. We also extended the self-consistent field theory to dynamical problems.We first checked the validity of the SCF theory by applying it to various problems in dense polymer systems. We studied micellar formation in tri-block copolymer solutions, Change in the surface tension by addition of block copolymers, interactions between polymer-grafted colloidal particles, and so on. We found that changes in the polymer conformation play important roles in interactions between colloidal particles and interfacial properties.Next, we tried to extend the SCF theory to dynamical problems. The simplest way of extending the SCF theory to dynamical problems is to use an assumption of the linear diffusion, i.e. a current of the segments is induced by the gradient of the chemical potential (Ficks law). Using this dynamical SCF theory, we studied a domain formation in thin polymer blend film on a solid surface, and complex domain formations induced by a competition between micro-and macro-phase separations in block copolymer blend. We observed similar phase separation dynamics and domain structures as in realistic systems. We also checked the validity of this dynamical model by comparing it with Rouse model.In a large deformation regime where the chain conformation is considerably deformed by external forces, the above dynamical SCF theory breaks down. In order to evaluate the degree of deformation of the chain conformation, we introduced non-isotropic bond-distribution functions. This new dynamical SCF theory is verified by studying a polymer brush system under shear deformation.