Volumetric 3D printing of a fluoropolymer and closed-loop chemical recycling of its fluorinated content
摘要
Fluorinated polymers are indispensable in fields such as microfluidics, electronics, and biomedical engineering. Yet, their chemical stability leads to long-term environmental persistence, rendering end-of-life management essential. In parallel, their insolubility and lack of melt behavior complicate fabrication into complex geometries, restricting their use in 3D printing. Here, a fluorinated photoresist is introduced that enables tomographic volumetric 3D printing with closed-loop chemical recycling of its fluorinated content. The photoresist—based on an alkene-functionalized fluorinated diol and a multifunctional thiol—supports rapid fabrication of centimeter-scale objects with reproducible feature sizes down to 56μm, among the smallest reported to date. Selective urethane hydrolysis under alkaline conditions yields ~97% recovery of the fluorinated monomer. The recovered monomer is re-functionalized and reprinted without loss of print fidelity, thermal stability, or mechanical performance. Volumetric 3D printed parts are biocompatible in vitro, supporting potential biomedical use. This represents the first demonstration of high-resolution tomographic volumetric printing of a fluoropolymer with closed-loop chemical recycling of its fluorinated content.