Innate Reprocessability in Engineering Thermosets

While valued for their durability and exceptional performance, crosslinked thermosets are challenging to recycle and reuse. Here, we unveil inherent reprocessability in industrially relevant polyolefin thermosets. Unlike prior methods, our approach eliminates the need to introduce exchangeable functionality to regenerate the material, relying instead on preserving the activity of the metathesis catalyst employed in the curing reaction. Frontal ring opening metathesis polymerization (FROMP) proves critical to preserving this activity. We explore conditions controlling catalytic viability to successfully reclaim performance across multiple generations of material, thus demonstrating long-term reprocessability. This straightforward and scalable remolding strategy is poised for widespread adoption. Given the anticipated growth in polyolefin thermosets, our findings represent an important conceptual advance in the pursuit of a fully circular lifecycle for thermoset polymers.