Compounding in plastics processing


For masterbatches and more. Dosing and mixing systems for challenging, continuous production processes, such as masterbatches.

During compounding, plastics are prepared for processing and their property profiles are specifically adjusted with the addition of aggregates (fillers, additives, reinforcements, etc.). More precisely, polymers and aggregates are fused and mixed and the discharged melt flow is granulated into plastic compounds.

Produced plastic raw materials are usually available as powder, salt, or coarse solids that cannot be processed in their present state. Compounding prepares these so they are ready to be processed and refines them by adding certain aggregates. The process is continuous and has multiple steps. The raw materials (raw plastic materials, fillers, additives, reinforcements, etc.) are placed in a cylinder with a screw where they are plasticized, dispersed, homogenized and degassed. Co-rotating double screws or multiple-screw wave systems (planet roller extruder, ring extruder, etc.) as well as co-kneaders with a rotatory and translational screw are used. The extrudate is discharged as a melt flow through a die. This is then granulated while hot under water, or when cool using a cutter. This makes a granular plastic compound that can be processed, usually in the shape of pearls or nuggets (hot) or cube-shaped (cold).

Preparing and refining plastic compounds; including the manufacture of loaded compounds (e.g. WPC) and granulated recyclate.

Thermoplastic raw polymers (granulate, powder, salt, etc.) are used for compounding, as well as additives, powder fillers, fibres and liquids.

Compounding normally produces granulated plastic compounds that are later used in plastic processing processes such as injection moulding, blow moulding or extrusion. Final products of compounding are, among others, pigment or additive masterbatches, filler or fibre-reinforced compounds, tailor-made masterbatches or granulated recyclate.

Diverse possibilities regarding dosing and mixing when making plastics and plastic compounds.

We at motan-colortronic provide extremely precise and consistent products for the areas dosing & mixing, as well as conveying. Precise, modular and flexible loss-in-weight dosing (GRAVIPLUS, SPECTROFLEX V, SPECTROFLEX G) are possibilities, as well as our pneumatic conveying systems for granules, powder or regrind.


Goal Preparation and refining of properties of a plastic by adding aggregates
Process Continuous and multi-step
Raw material Thermoplastic polymers (granules, powder, grit, etc.), additives, powder fillers, fibers, and liquids, but also regrind from plastic products
Final product Plastic compounds for further processing: pigment or additive masterbatches, filler or fiber-reinforced compounds, tailor-made masterbatches or recyclates
Compounding with motan-colortronic Continuous gravimetric dosing & mixing technology with high precision and consistency, modular and flexible loss-in-weight dosing (GRAVIPLUS, SPECTROFLEX V, SPECTROFLEX G), pneumatic conveying systems for granules, powder or regrind