Which processing aids are known for staying stable under high-temperature extrusion conditions?

Processing aids that are known to stay relatively stable under high-temperature extrusion usually include materials designed for thermal and oxidative resistance. Common examples are:

• Fluoropolymer-based processing aids

  • Very common in polyolefin extrusion
  • Good thermal stability and melt-flow improvement at elevated temperatures

• High-temperature waxes

  • Examples: polyethylene waxes, oxidized PE waxes, amide waxes
  • Used where moderate thermal stability is sufficient

• Silicone-based processing aids

  • Especially silicone masterbatches or siloxane additives
  • Often remain effective and stable at high processing temperatures

• Certain metal stearates

  • E.g. calcium stearate, zinc stearate
  • Can function as lubricants/processing aids, though thermal stability varies by polymer system

• High-temperature phosphate esters / ester lubricants

  • Used in some engineering polymers and PVC systems
  • Can offer better heat resistance than simpler lubricants

• Hindered phenol / phosphite stabilizer packages

  • More accurately stabilizers than classic processing aids, but often used together to maintain performance during extrusion

In practice, the “best” choice depends on the polymer type and extrusion temperature. If you want, I can narrow this down for a specific resin such as PVC, polyethylene, polypropylene, PET, or nylon.