Understanding the structure and mechanical properties of polymer networks is critical to a variety of soft material applications ranging from sustainability to impact mitigation. The polymer chemistry and structure of these entangled materials are essential to defining their mechanical and (re)use properties, yet the specific relationships are not well established, particularly as bonds break and the network dynamically transitions to a collection of discrete polymer chains. Model polymer networks, with well-defined chemistry and architecture, are needed to carry out quantitative measurements to establish design principles for programmable disentanglement or dissociation of network materials. We are interested in studying the structure and mechanical properties of polymer networks with defined molecular topologies (functionality, branching, and molecular mass distribution), as well as dynamic or reversible polymer chemistry that introduce labile sites vulnerable to catalysis and stimuli-responsive chain cleavage. Experimental methods for this opportunity include gel-permeation chromatography, nuclear magnetic resonance, small angle neutron and x-ray scattering, quasi-static mechanical testing, and high-rate impact testing.

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