In this study, we attempted to prepare a thermoplastic vulcanizate in a twin-screw extruder by determining the screw configuration on the basis of batch-mixer results. In this regard, two sets of information were used: (1) the time length, power consumption, and filling factor of different stages of the reactive blending process in the internal mixer and (2) the mean residence time and power consumption of the twin-screw extruder. Morphological features of the samples taken from the melt-mixing and dynamic vulcanization zones of the extruder with the selected screw configuration were found to be comparable with corresponding samples taken from an internal mixer reported in our previous study. The rheological and mechanical properties could provide valuable information to support the reliability of this study. (C) 2007 Wiley Periodicals, Inc.