End-of-Life Chemistry of Polytetrafluoroethylene: From Destruction to Fluorine Reuse
Polytetrafluoroethylene (PTFE) is one of the most chemically and thermally resilient synthetic materials. That resilience underpins its value in aggressive service environments, but it also complicates end-of-life treatment. The central challenge is not simply to remove the parent polymer, but to determine where fluorine and carbon go after carbon-fluorine (C-F) bond cleavage and whether those products are benign, controllable or useful. This Review organizes the emerging chemistry of PTFE end-of-life management around five distinct endpoints, namely parent disappearance, bulk defluorination, fluorine mineralization, fluoride recovery and fluorine reuse. It compares high-temperature destruction, molten-hydroxide mineralization, reductive defluorination and mechanochemical conversion through a common set of descriptors spanning fluorine mass balance, sink quality, carbon fate, process intensity and deployment plausibility. A consistent picture emerges in which thermal routes remain the benchmark for feed tolerance and rapid elimination, but their practical value depends on suppressing incomplete-destruction products and coupling bond cleavage to robust fluoride capture. Milder chemical and solid-state routes show that PTFE can also be directed into defined mineral sinks or directly reusable fluorinating reagents, although they are often constrained by interfacial transport, crystallinity and feed heterogeneity. Future progress will depend on treating PTFE not only as a recalcitrant waste, but as a concentrated fluorine reservoir whose end-of-life chemistry must unite selective bond activation with accountable fluorine stewardship.