Compound
Also called: Plastic compound, compounded granules, filled compound, reinforced compound
A compound is a plastic melt-blended with additives, fillers, reinforcements or other polymers to meet a specific property target.
A compound is a plastic that has been melt-mixed, usually in a twin-screw extruder, with other ingredients to achieve set properties. Ingredients may include fillers such as talc or calcium carbonate, glass fibre, impact modifiers, stabilisers, flame retardants, pigments or other polymers. The result is sold as granules.
Why it matters when buying recycled plastic
- Recycled compounds let manufacturers use recycled content while hitting a specification, for example a talc-filled PP for appliances or glass-filled nylon for automotive parts.
- Specify the properties you need, such as MFI, density, ash, tensile and impact, rather than only the filler percentage.
- Ask whether the base polymer is recycled, virgin or a blend, and in what ratio.
- Lot-to-lot consistency is critical; ask for a certificate of analysis per lot.
Common uses
Filled PP for furniture and appliances, PVC compounds for cables and footwear, TPR compounds for soles, and glass-filled nylon for engineering parts. A masterbatch is a related but more concentrated product.
Recycled compounds should be trialled on your own machines, since processing behaviour can differ from virgin compounds with similar data sheet values.