Networklike pattern formation in phase separating polymer solutions: A molecular dynamics study

The dynamics of phase separation of a quenched polymer solution is studied using a stochastic molecular dynamics simulation. At early times, the elastic nature of the polymer chains generates a networklike domain morphology for sufficiently dense polymer solutions. However, at late times, this network structure breaks up into disconnected polymer-rich domains to minimize the interfacial energy. Our simulations explain why different experiments carried out to different time regimes seem to produce contradictory results, and strongly indicate that the tore late-time growth kinetics of quenched polymer solutions belong to the same universality class of small molecular mixtures.