Renewable isosorbide-enchained semi-fluorinated aromatic ether polymers

Isosorbide-based renewable semi-fluorinated polymers were synthesized via base-mediated step-growth polycondensation of isosorbide diol monomer with bis-trifluorovinyl ether (TFVE) monomer in excellent yields. As the first example employing secondary alcohols in this addition/elimination polymerization affording fluorinated arylene vinylene ether (FAVE) polymers, reasonable to high-molecular weights (10–84 kDa) and reproducible glass transition temperatures (T_g) ranging from 120 to 130°C were achieved. Containing 23–31 wt.% renewable isosorbide repeat unit, the amorphous polymers are processable in common organic solvents and form tough, transparent films. Depending on basic conditions, these renewable semi-fluorinated polymers contain reactive fluoroalkene enchainment for post-polymerization functionalization and further retain the ability to thermally crosslink without the need for catalysts or initiators. Structural characterization of this complex asymmetric polymer was determined by multi-nuclear NMR including multiple 2D-NMR techniques. Renewable FAVE chemistry based on isosorbide presents an intriguing option for alternative renewable materials containing fluorine.