Masterbatch is solid or liquid additives used to color plastics (color masterbatch) or improve other properties of plastics (additive masterbatch). Masterbatch is a concentrated mixture of pigments and/or additives (20-90%) that is cooled and granulated after being absorbed into the carrier polymer by a thermal process. Masterbatches are available in a wide variety of carrier polymers including PE, PP, PS, SAN, PMMA, ABS, PET, PBT, PLA, PA, PES, EVA, TPU and specialty biopolymers.

The purpose of masterbatch production is to provide the most appropriate distribution of additives in the polymer matrix. Fine, powdery material often tends to agrommel and is therefore a difficult material to work with.

The poex inline twin screw extruder is the main component of the masterbatch line. It acts to homogenize, disperse, fluidize and disperse pigments/additives/fillers within the polymer matrix. This process is done either by premixing or by a separate feeding process.