Multi-Responsive Macromolecular Fluxional Networks as Novel Adaptive Polymeric Systems
Abstract
Numerous classes of polymeric materials contain chemical bonds between neighboring chains. These thermosets have desirable mechanical properties for a variety of applications, but cannot be reshaped, remolded, or recycled due to the permanent nature of covalent crosslinks. An alternative architecture would introduce dynamic covalent bonds that can transform a thermoset to a thermoplastic under certain conditions. These materials, appropriately termed covalent adaptable networks, function via bimolecular junction reorganization; thermosets have the capability to flow and relax stress at elevated temperatures. To improve material longevity, performance, and versatility, motifs that could undergo facile sigmatropic rearrangements would allow access to covalent adaptable networks that depend solely on unimolecular functionality. These Òshape-shiftingÓ networks may be realized by utilizing bullvalene, a rigid hydrocarbon that undergoes Cope rearrangements under ambient conditions, as a prototypical ÒfluxionalÓ crosslinker in mutli-responsive adaptable fluxional networks (MaF-Net). Despite finding applications in supramolecular chemistry, bullvalene and related fluxional hydrocarbon cages have yet to be exploited in crosslinked polymer architectures. This proposal aims to evaluate the impact of molecular pericyclic reactions on materials properties in the context of both dynamic vitrimer-like and covalent thermoset-like MaF-Nets utilizing heat, force, and/or light as stimuli.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 19, 2023
- Source ID
- W911NF2310106
Entities
People
- Matthew R. Golder
Organizations
- Army Contracting Command
- United States Army
- University of Washington