Jérôme Charmet

The widespread use of disposable facemasks during the COVID‐19 pandemic has led to environmental concern due to microplastic pollution. Biodegradable disposable facemasks are a first step to reducing the environmental impact of pandemics. Here, high‐performance facemask components based on novel poly(ester amide)s (PEA) grades synthesized from biosourced materials and processed into nonwoven facemask components are presented. PEA‐based polymers present an excellent compromise between mechanical performance and biodegradability. Importantly, the properties of the PEA can easily be tuned by changing the ratio of ester and amide, or by varying diol and diacid parts. Seven polymers are synthesized which are optimized for biodegradability and processability. Among them, two grades combines 1) electrospinning process compatibility with 2) full degradation within 35 days, using a normalized biodegradation test. The ultra‐thin filters thus developed are evaluated for performance on a custom‐made characterization bench. The filters achieve microparticle capture efficiency and air permeability comparable to commercial filters. Another PEA grade is optimized to reach optimal viscothermal properties that made it compatible with solvent‐free melt‐spinning process as demonstrated with continuous fiber production. Overall, this environmentally friendly solution paves the way for the fabrication of high‐performance fibers with excellent biodegradability for the next‐generation facemasks.