| We have worked to elucidate the relationships between polymer architecture and solution properties. We focus our efforts on both the effects of branching on single molecule structure and the effects of copolymer architecture on self-assembled micelles. To explore these relationships, we study series of rationally designed polymers using small-angle neutron scattering (SANS), neutron spin-echo (NSE) spectroscopy, and dynamic light scattering (DLS). Through these studies, we systematically isolate the architectural effects on the polymer solution properties.; In a branched polymer series, we investigate five isomeric hyperbranched cores with either dendrons or linear polymers attached to their surfaces, thus concentrating on the architectural feature of branch juncture placement. Dilute solution SANS studies reveal that the placement of the junctures alters the core size and polymer conformation within the cores. In semi-dilute solutions the intermolecular interactions and tendency for liquidlike structuring are affected by the core architecture. Complementary NSE studies show that the peculiarities in the statics of these systems are mirrored in their dynamics.; We have studied two copolymer systems to explore the impact of the copolymer architecture on their assembly. The first system comprises a polystyrene (PS) block copolymerized to a modified PS block with an imidazolium ionic liquid functionality (IL). SANS and DLS studies suggest that the copolymers form short and stiff elongated micelles in toluene solutions. The extended IL block in the core governs the micelle dimensions and sequesters water. The second copolymer system is a thermoresponsive diblock composed of both neutral and polyzwitterionic blocks. The complementary solubilities of these blocks lead to an inversion in the assembly with solution temperature modulation. The low temperature assemblies show features of wormlike chains. At high temperatures, the high molecular weight diblocks form spherical micelles, while the low molecular weight diblocks may exist as elongated structures. The neutral block length most strongly influences the micelle structure and geometry.; By studying a diverse collection of polymeric systems, we have systematically explored many variables of polymer architecture. Through our work, we have contributed to the understanding of the interplay between the architecture of polymers and their structure and dynamics. |
