Primary vs Secondary Antioxidants, and When Both

1. What decision is the buyer trying to make?

Whether to run a primary AO alone, a secondary AO alone, or a balanced primary + secondary system — and at what loading.

2. Which variables actually matter?

• Degradation stage being addressed (processing vs long-term service)
• Polymer, residence time, temperature
• Recycled content (%)
• Presence of metal contaminants (Cu, Fe) in cable / wire applications
• Interactions with UV package, colour, and food-contact rules

3. Which variables are commonly misunderstood?

• "One AO is enough" — for most polyolefin processes, a phenolic + phosphite pairing is standard.
• Higher loading is not always better — blooming and colour drift appear.
• Metal deactivators are sometimes required in wire & cable but often forgotten.

4. What should the buyer investigate next?

Whether the current AO ratio matches the real thermal history — and whether a metal deactivator is required.

5. What should be included in the RFQ?

Polymer + MFI · process + residence time · service temperature + life · recycled content · metal contact (cable/wire) · other additives present · regulatory scope · volume · benchmark grade.

Ending — Decision Graph Completeness

• Learned: stabilisation is a system, not a single additive.
• Investigate next: whether your system is balanced and correctly loaded.
• RFQ prep: 10 items above.