よくある質問

6月 30, 2026

酸化防止剤がポリマーの安定性をどのように改善するか

Why Polymers Degrade Through Oxidation

ポリマーの酸化は連鎖反応を伴います. Heat, 紫外線, 機械的剪断, または金属汚染によりフリーラジカルが生成される. These react with oxygen to form peroxy radicals, which continue the chain. Without antioxidants, これは黄ばみの原因になります, 脆化, melt flow changes, そして表面劣化.

Primary Antioxidants: Radical Scavengers

Hindered phenol antioxidants (酸化防止剤 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 (酸化防止剤 168): Fast-acting at high melt temperatures, excellent processing stabilizers
  • Thioesters (DSTDP, DLTDP): Cost-effective long-term thermal aging protection

Synergistic Systems

  • 酸化防止剤 1010 + 168: Most widely used polyolefin system
  • 酸化防止剤 1010 + DSTDP: Cost-effective long-term stabilization in PP/PE
  • 酸化防止剤 1010 + 168 + ハルス: Full stabilization for outdoor applications

Polymer-Specific Selection

  • PP: 1010 + 168 at 0.1–0.3% combined
  • PE: Combined systems; confirm by OIT testing for pipe/geomembrane applications
  • エンジニアリングプラスチック: Grades stable at 250–300°C (酸化防止剤 168 is key at these temperatures)

よくある質問

Do antioxidants provide UV protection?
いいえ. Antioxidants address thermal oxidative degradation only. For outdoor applications, UV absorbers and HALS stabilizers must be added separately.

サンケムへのお問い合わせ

SUNCHEM's team can help recommend the right antioxidant system for your polymer and application. お問い合わせ for technical support and samples.

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