(53k) Coarse-Grained Simulation of Self-Healing Supramolecular Polymers with Highly Branched Architectures

The utility of self-healing polymers is evident, with the ability of a material to dynamically heal a wound with minimal or no human intervention having significant benefit for that material’s longevity and environmental impact. Despite this, strategies for transformation of useful and market-ready commodity polymers into self-healable polymers are of limited availability. One strategy under active exploration is to modify commodity polymers into highly branched networks, taking advantage of strong, glassy cores at the heart of the networks, while retaining mobility at free ends on the periphery of the networks. Adding supramolecular interactions (in this work, hydrogen bonding) to those free ends enables self-healability, as these non-covalent attractions induce polymer material to repair a wounded interface. We perform large scale coarse-grained molecular dynamics simulations to interrogate the mechanical properties and molecular level self-healing processes of highly branched polymers with hydrogen-bonding ends. We explore the connection between polymer architecture, network properties, and hydrogen bonding strength on glass transition temperature, Young’s modulus, and self-healability. Furthermore, we discuss the possibility of inverse design of networks for optimizing mechanical strength and self-healing ability.

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.