Influence of Chain Architecture on the Kinetics of Chain Exchange Between BCC-Ordered Copolymer Micelles: A Dynamical Self-Consistent Mean-Field Theory Study

Motivated by recent time-resolved small-angle neutron scattering results, we study the kinetics of symmetric ABA and BAB triblock copolymer exchange between BCC-ordered spherical micelles using dynamical self-consistent field theory simulations. We characterize the equilibrium properties of micelles in pure melts of AB, ABA, and BAB copolymers, and systematically examine the decay time of the fraction of core (A) blocks remaining in their original micelle, as well as the chain self-diffusion constant, as a function of segregation. Differences in the equilibrium micelle structure between these cases complicate comparison of the dynamical behaviour for the different chain architectures. This complication is overcome by simulating tracer triblock copolymers in a constant background of BCC-ordered diblock micelles, allowing for direct comparison of the chain diffusion for the different chain architectures, as a function of segregation.