MONTE-CARLO SIMULATION OF PHASE-SEPARATION KINETICS IN A CONCENTRATEDPOLYMER-SOLUTION

Spinodal decomposition (SD) kinetics in a concentrated polymer solutio n was investigated with dynamic Monte Carlo simulation. It is found th at the positions of scattering peaks are altered during the early stag e of phase separation, which cannot be described by the classic Cahn-H illiard linearized theory quite well, whereas during the late stage SD induced by a deep off-critical quench, the structure factors can be s caled with Furukawa dynamic scaling law associated with a percolation morphology instead of with a non-continuous phase morphology, Our simu lation outputs agree basically with the experimental observations in t he pertinent Literature. It is also revealed that after a deep quench, chain coils shrink strikingly at first and then expand gradually duri ng phase separation. As a consequence, this paper demonstrates that th e dynamic Monte Carlo method is unique in detecting both chain configu rations and phase separation kinetics and thus very useful for elucida ting their relationship in mixtures containing macromolecules.