Enzyme-catalyzed polymerization: an opportunity for innovation

Abstract

—The application of enzymes in organic synthesis has attracted the attention of many research workers in recent years. Specific enzymatic catalysis is expected to synthesize polymers with high selectivity and/or novel structures. Up to now, the enzymatic synthesis of polyphenols, cellulose, lignin, and polypeptides, as well as non-natural polymers, has been successfully achieved. This review discusses the systematic synthesis of polyphenols using horseradish peroxidase-hydrogen peroxide (HRP-H2O2), the ring-opening polymerization of lactones using the enzyme lipase, and the successful synthesis of cellulose using the enzyme cellulase. The polyphenols enzymatically synthesized have been explored as substitutes of phenol-formaldehyde resins to eliminate the pollution caused by formaldehyde in the environment. Due to their unique π-conjugation nature, these polymers have potential applications in nonlinear optics and in the fabrication of light-emitting diodes. The enzymatic polymerizations using lipase have been expanded to ring-opening polymerization and copolymerization of medium-sized lactones yielding polyesters. It is predicted that enzymatic polymerization will revolutionize the polymer and plastics industries in the 21st century for the synthesis of novel polymers with specific properties.