Effects of Self-Assembly on Diffusion Mechanisms of Triblock Copolymers in Aqueous Solution

Molecular dynamics of self-assembling triblock copolymers in a mixture with water was explored using nuclear magnetic resonance (NMR) diffusometry with high-intensity field gradient pulses. With varying concentration, the diffusivities are found to cover 4 orders of magnitude. The dramatic changes in both the rates and patterns of polymer propagation can be attributed to their ordering in supermolecular formations and prove to be a sensitive means for probing structural and dynamic features of self-aggregation which only now, owing to recent progress in NMR diffusometry, have become accessible to direct observation.