十二角形の準結晶形質は,ポリ (スタイレン-b-イソプレン-b-スタイレン-b-エチレン酸化物) テトラブロックのテルポリマーである
1Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Journal of the American Chemical Society
|April 18, 2012
まとめ
新しい十二角形準結晶形状の形態は,ポリ (ステレン-b-イソプレン-b-ステレン-b-エチレン酸化物) (SISO) テトラブロックテラポリマーで発見されました. このユニークな構造は,12倍の回転対称性を示し,特定の温度範囲内で発生します.
科学分野:
- ポリマー科学は,ポリマー科学である.
- マテリアルサイエンス 材料科学
- クリスタルグラフィーです.
背景:
- ブロックコポリマーは,自己組織化して,秩序あるナノ構造を形成します.
- 準結晶相は合成ポリマーでは珍しい.
- ポリマー形態の理解は,材料の性質の鍵である.
研究 の 目的:
- SISOテトラブロック・テルポリマーにおける12角形の準結晶形状を特定し,特徴づけること.
- QC形成の温度範囲と条件を決定する.
- この複雑な包装の分子基盤を解明するために.
主な方法:
- 画像形態学の伝送電子顕微鏡 (TEM) について.
- 構造分析のための小角X線散射 (SAXS).
- 熱変異のためのダイナミック・メカニカル・スペクトロスコーピー (DMS).
主要な成果:
- ドデカゴナル準結晶 (QC) 形態は,SISOのテルポリマーで観察されました.
- QC状態は,六角形 (HEX) とシグマ (σ) 段階の間にある.
- TEMは,長距離変換順序なしの12倍対称性を明らかにしました.
結論:
- SISOのテトラブロック・テルポリマーは,十二角形の準結晶構造を形成することができる.
- 分子構造は,多様な包装対称性を可能にします.
- この発見は,ブロックコポリマーにおける既知の形態を拡張するものである.
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