Rational design of polymer networks and bottlebrush block copolymers

Abstract

Chapter 1: Introduction to Polymer Networks and Bottlebrush Block Copolymers We introduce polymer networks and the contribution of this author's thesis in the context of new polymer gel design and analysis of topological defects. We also introduce block copolymers and the key architectural differences between our branched bottlebrush design for block copolymer and liquid crystal block copolymer materials. Chapter 2: A dual role for 1,2,4,5-tetrazines in polymer networks: combining Diels-Alder reactions and metal coordination to generate functional supramolecular gels In this chapter we report the synthesis, characterization, and application of a new type of supramolecular metallogels using 1,2,4,5-tetrazines-containing polymers. This was the first example in our group of attempting to using metal-organic cages as crosslinking structures for polymer networks. Chapter 3: Loops Versus Branch Functionality in Model Click Hydrogels Here we report our work on quantifying topological defects in tri- and tetrafunctional networks and compare fundamental differences between such systems. We demonstrate the ability to count primary loop defects with a distribution of junction functionality. Chapter 4: Quantifying the Impact of Molecular Defects on Polymer Network Elasticity Based on our work in Chapter 3, we correlate the effect of molecular defects on a macroscopically measurable value: elasticity. We use our experimental techniques to help develop a new theory to accurately predict elasticity in end-linked networks. Chapter 5: Graft-through Synthesis and Assembly of Janus Bottlebrush Polymers from A-branch- B Diblock Macromonomers We synthesize branched macromonomers that contain two different polymers polymers to form bottlebrush block copolymers with a novel architecture. Bulk state and thin film self-assembly studies were performed and open the door to new, more complex bottlebrush block copolymers. Chapter 6: Synthesis of Liquid Crystal-Containing A-branch-B Janus Bottlebrush Block Copolymers We synthesize macromonomers that contains a polymer and a liquid crystal and polymerize the branched macromonomers to form Janus-type bottlebrush block copolymers. The bulk state self-assembly behavior was characterized and the alignment of the bottlebrush polymers under a magnetic field is explored.