Self-Assembly and Dynamics Driven by Oligocarbonate–Fluorene End-Functionalized Poly(ethylene glycol) ABA Triblock Copolymers
journal contributionposted on 03.02.2017, 19:33 by Guangmin Wei, Shrinivas Venkataraman, Yi Yan Yang, James L. Hedrick, Vivek M. Prabhu
The closed assembly transition from polymers to micelles and open assembly to clusters are induced by supramolecular π–π stacking in model oligocarbonate–fluorene (F-TMC) end-group telechelic polymers. The critical micelle concentration (CMC) depends on the F-TMC degree of polymerization that further controls the weak micelle association and strong clustering of micelles regimes. Clustering follows a multistep equilibria model with average size scaling with concentration reduced by the CMC as R ∼ (c/CMC)1/4. The F-TMC packing that drives the supramolecular self-assembly from polymers to micelles stabilizes these larger clusters. The clusters are characterized by internal relaxations by dynamic light scattering. This signifies that while F-TMC groups drive the clustering, the micelles interconnected via F-TMC bridging interactions remain coupled to the extent that the clusters relax via Rouse–Zimm dynamics, reminiscent of microgels.