Use of a batch-stirred reactor to rationally tailor biocatalytic polytransesterification

Despite favorable thermodynamics, high-molecular weight and low-dispersity polyesters are difficult to synthesize biocatalytically in organic solvents . We have reported previously that the elimination of solvent can improve t he kinetics and apparent equilibrium significantly (Chaudhary et al., 1997a ). We now present the design and use of a batch-stirred enzyme reactor to c ontrol the biocatalytic polymerization. Using the reactor, polyester having a molecular weight of 23,400 Da and a polydispersity of 1.69 was synthesiz ed in only 1 h at 60 degrees C. Additional factors like enzyme-deactivation kinetics, enzyme specificity, and initial exothermicity were investigated to develop a better understanding of this complex reaction system. (C) 2000 John Wiley & Sons, Inc.