Soft by Design - Tunable elastomers and plastomers with bottlebrush topology

Summary

Polymers, which are large macromolecules made up of repeating units called monomers, are a significant part of our daily lives ranging from commodity plastics to advanced functional materials. Polymers exhibit a wide range of material properties that stem from diverse physicochemical features in their molecular structure which can be tuned both chemically through their chemical composition and physically through their molecular architecture or topology. One of the complex polymer chain architectures is a bottlebrush topology where a polymer backbone is highly grafted with relatively short side chains. This thesis exploits the topological tunability of bottlebrush networks, formed through the chemical or physical crosslinking of bottlebrush chains, to program a desired material property such as stiffness. One of the unique features of bottlebrush networks is the ability to produce exceptionally soft materials without the incorporation of any solvent or additives. In addition, bottlebrush polymers provide extensive molecular tunability due to multiple combinations of topological parameters. By providing synthesis routines that ensure well-controlled and programmable molecular architecture, this dissertation provides design concepts of super-soft bottlebrush materials with precise and predictable stiffness and new soft materials which are compatible with 3D printing techniques. The outcomes of this dissertation not only highlight the unique capabilities of super-soft bottlebrush material but also establish a foundation for their utilization in various innovative applications.