Network Topology and Percolation in Model Covalent\nAdaptable Networks

Incorporating\ndynamic covalent linkages into thermosets can endow\npreviously unrecyclable materials with new functionality and reprocessing\noptions. Recent work has shown that the properties of the resulting\ncovalent adaptable networks (CANs) are highly dependent on network\ntopology, specifically the phenomenon of percolation, when permanent\nlinkages form a connected skeleton that spans the material. Here,\nwe use a model glassy disulfide based CAN to assess the merits of\nmean-field percolation theory as a tool to describe the network topology\nof CANs. After challenging the theory with both experimental data\nand a coarse-grained molecular dynamics simulation, we find that the\nmean-field approach is surprisingly accurate, despite its simplifying\nassumptions. The theory is particularly well suited to the unique\ncontext of mixed-composition CANs and provides practical guidance\non how to design for reprocessability.