"Green" Synthesis of Bisphenol Polymers and Copolymers, Mediated by Supramolecular Complexes of Laccase and Linear-Dendritic Block Copolymers

This chapter describes our recent advances on the utilization of polymer-modified laccase complexes for the "green" polymerization of strongly hydrophobic bisphenolic compounds (bisphenol A and stilbestrol) in aqueous systems. Linear-dendritic AB and ABC copolymers, composed of poly(ethylene oxide) and dendritic poly(benzyl ether)s of generations 3 and 2 (G3-PEO13k and G3-PEO13k-G2) easily form stable complex with laccase, isolated from Trametes versicolor upon simple mixing and stirring. Compared to the native enzyme these supramolecular systems show improved stability, activity, and overall simplicity in product separation and isolation. The products formed have molecular weights between 500 and 6000 D and are structurally characterized by size-exclusion chromatography in combination with NMR and FT-IR. It is found that the polymers contain predominantly unperturbed phenolic groups suggesting a chain growth mechanism through prevailing C-C coupling. A one-pot copolymerization of bisphenol A and diethylstilbestrol yields copolymers with interesting application potential as macroligands and/or macromonomers.