Simulation of the Kinetics of Chain Exchange Between Triblock Copolymer Micelles using Dynamical Self-Consistent Mean-Field Theory

Motivated by recent experiments, we study the kinetics of chain exchange between BCC-ordered micelles in asymmetric ABA and BAB triblock copolymer melts using dynamical self-consistent field theory (dSCFT). dSCFT reduces the problem of many interacting chains to that of the motion of a single chain under the influence of a dynamical mean force field determined self-consistently from the other chains. This approximation enables us to simulate a large ensemble of long chains for long times. After characterizing the equilibrium properties, we systematically examine the decay time of the fraction of core (A) blocks remaining in their original micelle. For BAB, we examine the influence of the length of the second corona block on this decay. We compare to analogous AB diblock copolymers, and comment on the effect of chain architecture. For ABA, we investigate the scenario of sequential core block extraction. In both cases, we characterize the configuration of the core block as it extracts and diffuses between micelles, and comment on the free energy barrier to chain extraction.