Compounding in plastics processing


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

Process description

Plastic compounding is a continuous, multi-stage process for the production plastic formulations by mixing polymers and additives in a molten state using twin screw extruders. 

Typical end products

The end products are pellets or granules for later use in other plastic processes, such as injection moulding or extrusion. For example: mono-pigment and additive masterbatches, filler and fibre reinforced compounds and tailor-made masterbatches. Typically short run lot sizes (weight) are produced. 


The raw materials are fed into the heated barrel of a twin screw extruder. Here the recipe will be mixed to achieve a homogenous blend and the molten plastic forced through a die. The extrudate is cooled and then pelletized. 

Typical materials being processed

Use of raw polymers, regrind and compounds but also powders, fibres, liquids and gases. 

Description of motan system/equipment used

Drying, conveying as well as dosing and mixing systems with highest accuracy. 

Typical dosing & mixing units

Highly accurate, complex and flexible loss-in-weight dosing & mixing systems (GRAVIPLUS, SPECTROFLEX V, SPECTROFLEX G).