Ordering of viscous liquid mixtures and polymer blend films.

摘要

My dissertation primarily includes four parts. First, I have numerically investigated the influence of a steady shear flow on the phase separation of viscous liquid mixtures. Layered domains grow as a power law with time in agreement with experimental results. Excess viscosity induced by the anisotropy of the system has also been investigated and a scaling law with shear rate has been found. Second, computer simulations of domain growth of block copolymer system under a steady shear have been performed. Lamellae are formed through linking and rejoining. In steady state, the power exponent of the thickness of lamellae depends solely on the chain length of the copolymer molecules. Third, I have presented detailed numerical results for phase separation of critical thin polymer blend films on patterned surfaces. The emphasis of this work is on the late stage morphology, i.e. how the late-time morphology depends on the geometry of the patterned substrate. The interplay between pattern formation and cooling mechanism has been investigated. The implications on the experimental situations have been discussed. Finally, I have carried out simulations of kinetics of phase separation of polymer blend films with hydrodynamic interactions being included in the model. Hydrodynamics-driven coarsening leads to a different exponent for the wetting layer growth.