Poly(ethylene furanoate) (PEF): Advances in Synthesis, Properties, Recycling, Applications, and Future Challenges.

The increasing concern over plastic pollution mostly due to extensive use of petroleum-based poly-(ethylene terephthalate) (PET) has intensified the search for sustainable biobased alternatives. Poly-(ethylene furanoate) (PEF), a fully biobased polyester derived from renewable feedstocks, has emerged as one of the most promising candidates. With superior gas-barrier performance, strong mechanical properties, and the potential for lower carbon emissions, PEF has attracted significant attention as a viable material to replace PET in several applications. This perspective presents an up-to-date and comprehensive overview of scientific and technological developments in PEF, tracing progress from its early discovery to its current industrial relevance. Particular emphasis is placed on the chemistry of PEF synthesis, including recent advances in greener pathways, as well as the structure-property relationships that refer to its superior thermal, mechanical, and barrier properties compared to PET. Performance characteristics arising from chemical structure and molecular modifications are also discussed. The review further examines the present landscape of PEF recycling, covering mechanical, chemical, and emerging enzymatic methods and integrates findings from recent life cycle assessment and techno-economic analysis studies to evaluate its environmental and economic viability. Industrial applications and associated challenges are explored, with a focus on packaging, where PEF's barrier and mechanical advantages offer clear benefits over PET and multilayer systems. The paper concludes by outlining key research gaps that must be addressed to enable scalable, circular, and industrial deployment of the PEF.