The road to material conquest of twin-screw extruders: from PVC to environmentally friendly biodegradable materials

1. Twin-screw extruder PVC pipe processing: balance between high shear and self-cleaning
High shear plasticization: The counter-rotating twin screws generate strong shear force through the screw ridges and screw grooves, quickly crush the PVC resin particles and achieve uniform plasticization, which is suitable for the processing of high-filling formulas such as calcium carbonate.
Self-cleaning design: The reverse movement of the meshing area can remove internal residues, avoid PVC decomposition due to local overheating, and ensure continuous production stability.
The segmented heating and cooling design can accurately control the PVC melt temperature, prevent coking, and harm the material. The vacuum exhaust system effectively removes volatile gases such as hydrogen chloride and improves surface smoothness.

2. Degradable plastic processing: shear and reactive extrusion synergy
Low shear blending: The co-rotating twin screws are used with large pitch thread elements to reduce mechanical damage to the PLA molecular chain.
Reaction extrusion technology: Through the dynamic blending of molten PBAT and PLA, combined with the addition of chain extenders, molecular chain crosslinking is achieved to improve material toughness.
Vacuum devolatilization optimization: The multi-stage exhaust design can remove moisture generated by starch degradation and prevent the generation of bubbles.

3. Technological breakthrough: modular design and material diversity
Shearing elements: Meshing disc elements are used for dispersed mixing of high-filling formulas, and toothed elements are suitable for uniform distribution of fiber-reinforced materials.
Conveying elements: Long pitch threads are used for rapid melt conveying, and reverse thread elements enhance melt reflux and extend reaction time.
Application of synthetic gear oil: Reduce the loss caused by friction, so that the energy consumption of twin-screw extruders is lower than that of traditional models.