Additive Manufacturing of Degradable, Recyclable Poly(dicyclopentadiene) Thermosets via Photoinitiated Ring-Opening Metathesis Polymerization

Additive manufacturing has enabled the quick and efficient development of polymeric components. However, with the ongoing plastics pollution crisis, it has become increasingly important to consider the end-of-life cycle of these materials. This is especially true for high performance thermoset materials, which are generally difficult to reprocess, break down, and recycle. PhotoROMP has recently been introduced as a promising method for vat photopolymerization of high-performance thermoset pDCPD. The ability to incorporate cyclic comonomers with cleavable units, such as DHF, has also enabled degradation of printed components. Here, we explore a recently developed cyclic silyl ether comonomer permitting degradation of pDCPD networks and further recycling of broken-down material. We demonstrate the ability to print, degrade, and reprint pDCPD components with recycled materials, enabling efficient and sustainable additive manufacturing of these important thermosets.<br/> <br/><i>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.</i>