Polymer derived thermosets (e.g. two-part epoxies, vulcanizable rubbers, polyurethanes, etc.) and thermoset composites are classes of materials that contain intermolecular chemical crosslinks, which impart excellent thermal, chemical, and mechanical stability. Due to these robust properties, these classes of materials often find use in harsh applications and environments; however, a direct consequence of this robustness is the tendency for thermoset materials to persist in the environment with very slow degradation over long periods of time. Efforts throughout the chemical community are currently aimed at addressing the balance between long term material performance and environmental sustainability.<br/>In this talk, we describe the incorporation of a potentially triggerable degradation pathway into epoxy-amine thermoset chemistries, through the use of boric acid templating. Under pH neutral to alkaline conditions, the boron species could act as a removable scaffold, and the resulting porous network structure could be more susceptible to environmental degradation. Along with improving environmental degradability, this method could also find use in the areas of tunable membranes and carbon capture technologies.<br/>In this work, we demonstrated the formation of novel boron species from neat mixing of amine compounds with boric acid, including one complex that appears highly stable under nitrogen atmosphere up to 600 °C. We describe the degradation pathways of cured epoxy composites under static and dynamic solvent conditions, as well as the thermal properties of various epoxy composites with increasing amount of boric acid.

Sustainable functional epoxies through boric acid templating

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.