Thiol-Trifluorovinyl Ether (Thiol-TFVE) Photochemistry: A New Route to Semifluorinated Materials

摘要

Fluorinated polymers have found prolific use in many high performance applications due to their mechanical strength, high thermal stability, and chemical stability. While desirable, fully fluorinated polymers tend to be highly crystalline, resulting in difficult processing conditions. Semi-fluorinated polymers, however, show improved processing conditions by remaining amorphous, yet demonstrate analogous properties to their fully fluorinated counterparts. Herein, we propose the use of thiol-ene chemistry as a viable route to synthesize semi-fluorinated materials. Specifically, we demonstrate the addition of a thiyl radical to the CF2 end of an aromatic trifluorovinyl ether (TFVE) group in accordance with the thiol-ene radical mechanism. The mechanism of addition is confirmed by 1H and 19F NMR by careful consideration of the spectrum splitting patterns, and real-time FTIR and thermomechanical analysis reveal reaction kinetics and network properties similar to that of a traditional thiol-ene network.