Mixers in the HAAKE PolyLab QC system perform mixing, kneading, compounding, and plasticizing. A standard test involves running the mixer at a set speed (shear rate) over time, measuring the material’s torque response. While the mixing chamber maintains precise temperature control via independent heating and cooling zones, frictional heat generates a measurable change in the material’s melt temperature. This resulting “Rheogram” (torque and melt temperature plotted against time at a constant speed) provides a unique “fingerprint” for different materials and blends, commonly used in quality control for incoming and outgoing product inspection. By analyzing the melting behavior, energy consumption, and melt viscosity (recorded torque), users can objectively measure and quantify the effects of various additives and their concentrations.