Characterization of phenolic polymers synthesized by enzyme-mediated reactions in bulk solvents and at oil-water interfaces

Phenolic polymers are synthesized from horseradish peroxidase-catalyzed reactions in the presence of hydrogen peroxide. The reactions are carried out in homogeneous mixtures of water and polar solvents such as DMF as well as at the oil-water interface of AOT/isooctane reversed micelles and isooctane-water biphasic systems. Polymer characteristics are analyzed using thermal, spectroscopic and chromatographic techniques. Polymer molecular weight dependence on the reaction medium composition is demonstrated for poly (p-ethylphenol) and poly (m-cresol). It is shown that thermal curing of polymers leads to cross-linking, and as a result, there is a significant increase in molecular weight. Cross-linking appears to be directly to the aromatic rings, and not via ether links, as inferred from infrared spectra. A process scheme for the production, under controlled conditions, of phenolic polymers in ethanol-water mixtures is presented. The process allows enhanced monomer conversions and ability to tailor polymer molecular weight. Possible applications for phenolic polymers are discussed.