<p>A disc cage final polycondensation reactor comprises an inclosed horizontal barrel having a feed inlet, a product outlet and an air outlet. A stirring device including stirring baskets and driving axles is disposed inside the barrel. The stirring baskets constitute of the baskets for low, medial and high viscous materials respectively. The driving axles constitute of the axles for the reaction zone of low and medial viscous materials and the reaction zone of high viscous materials respectively. Both the basket for low viscous materials and the basket for medial viscous materials are driven by the driving axle for low and medial viscous materials to carry out stirring. The basket for high viscous materials is driven by the driving axle for high viscous materials to carry out stirring.</p>
