A steady-state two-phase model has been developed for a continuous finishing stage of the melt polycondensation process that consists of two rotating-disk reactors in series. Each reactor has multiple reaction zones with different types of rotating disks to establish plug flow profiles and to facilitate the removal of volatile reaction byproducts. The effect on reactor performance of varying the mass transfer parameter was found to be small for the reaction conditions used. The simulation results show that the use of two reactors offers increased flexibility in reactor operations to obtain the desired polymer properties. Although the proposed model has not been fully validated with experimental or plant data, it has illustrated that the complex multizone reactor system can be easily modeled by the two-phase modeling technique and that added physical insights can be made through numerical model simulations. (C) 2003 Wiley Periodicals Inc.