Researchers at Colorado State University have developed chemically recyclable polymers that can be depolymerized back to their monomer building-blocks with high selectivity, purity, and efficiency, addressing global plastics pollution and resource depletion issues. By carefully designing polymer structures and catalyst systems, they achieved high-performance polythioesters with exceptional mechanical properties while maintaining full chemical recyclability.
Owing to their outstanding and versatile properties, synthetic polymeric materials meet the demands of end consumer products and play a key role in modern life and the global economy. However, synthetic polymers are largely based on petroleum resources, which are rapidly depleting due to ever increasing energy demands. Likewise, the tremendous growth of non-biodegradable single-use plastics poses a threat to the environment. Addressing end-of-life issues by gradually replacing petroleum-based polymers with those derived from renewable resources and with built-in end-of-life solutions of plastics is crucial for transitioning to a circular economy.
Inspired by present challenges, the group set out to create high-performance circular polymers with both intrinsic chemical recyclability and crystallinity. Researchers have designed a unique class of polythioester materials derived from a bridged bicyclic thiolactone monomer, 2-thiabicyclo[2.2.1]heptan-3-one (BTL). These polythioesters have both intrinsic chemical recyclability and crystallinity as well as an unusual set of combined high-performance properties such as high thermal stability, crystallinity, strength, ductility, and toughness. The bridged bicyclic monomer framework increases not only the polymerizability and stereoselectivity but also the chemical recyclability and selectivity due to its enhanced ring strain and the presence of the five-member lactone ring restricted to the cis configuration. Additionally, the bridged bicyclic system provides the rigidity in the polymer backbone for enhanced thermal and mechanical properties, while the cyclopentylene rings and sulfur in the polymer render tacticity-independent intrinsic crystallinity Normally this combination of properties requires a composite of materials due to structure/property trade-offs, but for this innovation that have been obtained in a single material.
Available for Licensing
TRL: 3
Eugene Y Chen
Changxia Shi
Aly Hoeher
Aly.Hoeher@colostate.eduÂ
970-491-7100