熱固体の治癒と組み立てのための金属触媒トランスエステル化
Mathieu Capelot1, Damien Montarnal, François Tournilhac
1Matière Molle et Chimie (UMR 7167 ESPCI-CNRS), Ecole Supérieure de Physique et Chimie Industrielles de la Ville de Paris ESPCI ParisTech, 10 rue Vauquelin, 75005 Paris, France.
Journal of the American Chemical Society
|April 28, 2012
まとめ
結合交換反応の触媒制御により,交絡ポリマーの修復が可能になる. これにより,エポキシ熱セットの適応性のある溶接と組み立てが可能になり,熱プラスチックよりも利点があります.
科学分野:
- ポリマー化学のポリマー化学について
- マテリアルサイエンス 材料科学
背景:
- エポキシ熱セットなどのクロスリンクされたポリマーネットワークは耐久性で知られていますが,通常は自己治癒能力がありません.
- 伝統的な熱セットは,固められた後に修復または再処理が困難であり,その用途と寿命を制限します.
研究 の 目的:
- エポキシ熱固体材料における自己治癒のための結合交換反応の触媒制御を調査する.
- 温度に依存するヒーリング運動を実証し,触媒濃度の影響を調査する.
主な方法:
- エポキシ酸およびエポキシアンヒドリド熱固体ネットワークにおける結合交換反応を促進するために,トランスエステル化触媒を使用した.
- 高温と低温の両方で治癒能力を研究しました.
- 治癒プロセスの運動学を分析するためにモデル分子を採用した.
主要な成果:
- トランスエステル化による高温でのクロスリンクされたエポキシ熱性セットの効果的な治癒を達成しました.
- 観察された遅い交換反応と,より低い温度での古典的な熱固体特性.
- 治癒運動がトランスエステル化反応速度と直接相関していることが確認されました.
- 触媒濃度が溶接および組立プロセスを制御することを示した.
結論:
- 結合交換反応の触媒制御は,エポキシ熱セットのヒーリングに有効なメカニズムを提供します.
- 温度に依存する運動学は,調整可能なヒーリングと処理を可能にします.
- このアプローチは,熱プラスチックと比較して,エポキシ熱セットの組立において,より高い制御と柔軟性を提供します.
関連する概念動画
01:13Olefin Metathesis Polymerization: Overview
Recently, the development of olefin metathesis polymerization advanced the field of polymer synthesis. Simply put, the reorganization of substituents on their double bonds between two olefins in the presence of a catalyst is known as the olefin metathesis reaction. The use of metathesis reaction for polymer synthesis is called olefin metathesis polymerization.
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists of a...
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00:53Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)
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Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
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The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
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01:16Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)
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01:22Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction
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02:36Oxymercuration-Reduction of Alkenes
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