A research team at the University of Illinois at Urbana-Champaign (led by Prof. Jeffrey S. Moore with postdocs Yuting Zhou and Zhenchuang Xu) has developed an electrochemical method to convert low-value oligomer fragments from carbon-fiber reinforced plastic (CFRP) waste into polymer networks with improved mechanical properties. The results, published in Nature Synthesis, show how modifying polymer backbones directly at carbon–hydrogen sites can restore performance and enable reprocessing.
Zhou, Y., Xu, Z., & Moore, J. S. (2025). Dual C–H functionalization of polyolefins for covalent adaptable network formation via cooperative electrolysis. Nature Synthesis. https://doi.org/10.1038/s44160-025-00876-7
High-performance composite materials like CFRPs are valued for their strength-to-weight ratio and durability, which makes them critical in aerospace, transportation, wind turbines, and other demanding applications. However, those same properties make them difficult to recycle. When CFRPs reach end of life, the carbon fibers are often recovered but the polymer matrix degrades into oligomer fragments. These fragments lack the mechanical strength and reactivity of the original networked polymer, and typical recycling routes yield low-value waste or require high input of energy or harsh conditions.
Chemistry professor at University of Illinois Urbana-Champaign, Jeffrey S. Moore stated,
“This closes a critical loop in the life cycle of carbon fiber composites, which are widely used in wind energy, transportation, and aerospace”.
In recent years, there’s been growing interest in circular materials and polymer upcycling: turning “waste” fragments not merely into lower-grade fillers, but into higher performance materials again. Electrochemistry offers one route, because it can drive chemical transformations under milder conditions and with more control.
Moore, Zhou, Xu and colleagues targeted the oligomer fragments left after deconstructing CFRPs. These fragments contain repeating molecular units (monomers) but are shorter chains, often branched, with limited capacity to form strong, crosslinked polymer networks. What the team has done is apply an electrolysis-based chemical modification directly to the oligomer backbone, inserting two functional groups at specific carbon–hydrogen (C–H) bond sites.
They used a process called dual C–H functionalization to install groups that allow the fragments to crosslink into a covalently adaptable network (CAN). Such networks recover mechanical integrity and allow reprocessing; meaning that after modification, materials can be reshaped or healed to some degree, rather than being one-time use.
The research shows that branched oligomers (which arise from CFRP breakdown) have tertiary allylic C–H sites that are more reactive than expected, which is significant: it means these sites can be targeted under manageable chemical conditions. The result is materials with enhanced mechanical performance compared to the unmodified oligomers, plus the capacity for reuse or reprocessing.
This work is described in the article “Dual C–H functionalization of polyolefins for covalent adaptable network formation via cooperative electrolysis.” Supporting commentary (for example via the University of Illinois Department of Chemistry) confirms the details of how modified oligomers can form new networks and regain strength.
Other recent studies help provide context. There has been work on upcycling commodity polymers such as PET and polycarbonate into engineering plastics via chemical routes. For example, a separate study developed a strategy to convert waste polycarbonate and PET into polyarylate with good transparency, thermal stability, and flame retardancy using a metal-free ionic liquid catalyst, and doing so while incorporating additive impurities instead of fully purifying recovered monomers.
Another line of research has focused on converting waste PET into biodegradable polymers such as polyglycolic acid (PGA), by electrochemical methods. Such studies address scalability, reaction efficiency, selectivity, and also separation/purification of products.
These complementary works show that polymer upcycling is emerging across multiple polymer types, and the new CFRP oligomer backbone editing adds a new tool to that toolkit.
One of the key strengths of the Illinois work is that it modifies fragments left over after composite recycling rather than discarding or heavily processing them; this improves material circularity. Also, direct C–H functionalization on the oligomer backbone is chemically challenging, so achieving this in a scalable, cooperative electrolysis method is a meaningful advance.
Because the resulting polymer networks are covalently adaptable, there is potential for re-processing, repair, or reshaping, which adds to the lifetime of the material and reduces waste. Applications could include components that currently use CFRPs but where repair or reuse is limited, protective coatings, or composite panels with adjustable or repairable properties.
However, there are open questions. It remains to be seen how these modified materials perform under long-term mechanical stress, in varied environmental conditions (moisture, UV, temperature cycling), or for safety-critical applications. Scaling from laboratory electrolysis and proof-of-concept materials to industrial scale is nontrivial: issues of cost, energy input, throughput, electrode stability, and consistency will need to be resolved. Also, the method has so far been demonstrated on particular oligomer types; whether oligomers from different composite types behave similarly remains to be tested.
The team is exploring extending the method to other polymer waste streams beyond CFRP oligomers, such as high-impact polymers or blended polymer wastes. Further work will likely include mechanical testing under real-world conditions (fatigue, wear), assessing durability, and optimizing cost and energy consumption. Integration with industrial composite recycling operations will be another step: ideally the chemical editing process could be built into workflows that already recover carbon fibers, reducing overall waste and cost.
The University of Illinois team has introduced an electrochemical approach to convert low-value oligomer fragments from carbon-fiber composite waste into higher performance, re-processable materials through direct backbone functionalization. Coupled with other recent advances in polymer upcycling (such as chemical upcycling of PET and polycarbonate), this work contributes to a growing toolbox for more sustainable polymer lifecycle management. While there is more to be done before industrial adoption, the method represents important progress toward closing the loop on composite materials.
Adrian graduated with a Masters Degree (1st Class Honours) in Chemical Engineering from Chester University along with Harris. His master’s research aimed to develop a standardadised clean water oxygenation transfer procedure to test bubble diffusers that are currently used in the wastewater industry commercial market. He has also undergone placments in both US and China primarely focused within the R&D department and is an associate member of the Institute of Chemical Engineers (IChemE).
