Compounding machinery for Rigid PVC

During the first half of the nineteenth century the creation of PVC from vinyl chloride (VC) was first described. Large-scale PVC production started in 1928 in the USA and 1930 in Germany. By the time the Second World War ended, it was already the most-produced plastic. With a chlorine content of 56.7% molar mass, PVC is a welcome co-product in chlorine chemistry. Due to their low content of hydrocarbon-based components, PVC materials have a comparatively favourable energy balance and carbon dioxide footprint.

Rigid PVC (PVC-U) is produced in a compounding machinery by hot/cold mixing in the powder phase. For all subsequent processes requiring pellets, such as injection moulding, this is followed by compounding and pelletizing on a Buss Kneader. This two-stage compounding process likewise applies in the case of high filler content or specific quality demands. For simpler formulations, premixing in the powder phase may be sufficient.