This kind of batch-type operation allows researches to study several process parameters (e.g. foaming, discoloration and the influence of catalysts/additives on the polymerization). All process parameters are digitally stored and online graphically represented (product temperature, distillation column temperature, stir rate, torque, vacuum). When finished the polymer is extruded from the vessel and cooled in a water bath. The polyester strand is then pelletized into chips. Enough material is available in this way for a first evaluation (solution viscosity, thermal behavior, solid-stating behavior). Polyesters can be produced starting from DMT (dimethyl terephthalate). Next to PET, polyesters like PEF, PEN, PTT, PBT, PBS can be produced for evaluation purposes. This is the ideal equipment to screen new (biobased) monomers and the polymers made thereof.