How Antioxidants Improve Polymer Stability
Why Polymers Degrade Through Oxidation
Polymer oxidation follows a chain reaction. Heat, UV radiation, mechanical shear, or metal contamination generates free radicals. These react with oxygen to form peroxy radicals, which continue the chain. Without antioxidants, this leads to yellowing, embrittlement, melt flow changes, and surface degradation.
Primary Antioxidants: Radical Scavengers
Hindered phenol antioxidants (항산화제 1010, 1076, 1098) donate hydrogen atoms to peroxy radicals, converting them into stable molecules and breaking the chain reaction. They are the first line of defence against oxidative degradation.
Secondary Antioxidants: Hydroperoxide Decomposers
Secondary antioxidants address hydroperoxides — the key intermediates that reinitiate radical chains if left unchecked:
- Phosphites (항산화제 168): Fast-acting at high melt temperatures, excellent processing stabilizers
- 티오 에스테르 (DSTDP, DLTDP): Cost-effective long-term thermal aging protection
Synergistic Systems
- 항산화제 1010 + 168: Most widely used polyolefin system
- 항산화제 1010 + DSTDP: Cost-effective long-term stabilization in PP/PE
- 항산화제 1010 + 168 + 할스: Full stabilization for outdoor applications
Polymer-Specific Selection
- PP: 1010 + 168 at 0.1–0.3% combined
- 체육: Combined systems; confirm by OIT testing for pipe/geomembrane applications
- Engineering plastics: Grades stable at 250–300°C (항산화제 168 is key at these temperatures)
자주하는 질문
Do antioxidants provide UV protection?
No. Antioxidants address thermal oxidative degradation only. For outdoor applications, UV absorbers and HALS stabilizers must be added separately.
Contact SUNCHEM
SUNCHEM's team can help recommend the right antioxidant system for your polymer and application. 저희에게 연락하십시오 for technical support and samples.