ABAトライブロック共ポリマーの自己組み立てにブロックポリ分散性の予期せぬ影響
Joan M Widin1, Adam K Schmitt, Andrew L Schmitt
1Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|January 28, 2012
まとめ
ブロックコポリマー合成は,鎖の長さの変動につながる可能性があります. ポリディスパースSBSトライブロック共ポリマーは,自己組み立てナノ構造物の安定性を高め,単分散材料の必要性に異議を唱えます.
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
- ナノテクノロジー ナノテクノロジー
背景:
- 制御されたポリメリゼーション方法は,機能ブロックコポリマー合成を可能にします.
- 鎖の長さの異質性 (多分散性) は一般的ですが,自己組み立てに対するその影響はあまり理解されていません.
- モノディスパースブロックコポリマーには,よく定義された自己組み立て行動があります.
研究 の 目的:
- スタイレン・ブタジレン・スタイレン (SBS) トリブロック共ポリマーの溶融相自己組み立てを,広範なポリ分散性Bブロックで調査する.
- 鎖の長さの異質性がブロックコポリマーの自己組み立てと材料の安定性に与える影響を決定する.
- ポリディスパースSBSトライブロック共ポリマーの形態図を探求する.
主な方法:
- SBSトライブロックコポリマーを合成し,ポリ (1,4-ブタディエネ) 含有量とポリ分散性を制御します.
- 構造分析のためのシンクロトロン小角X線散射 (SAXS).
- 形状の特徴化のための伝送電子顕微鏡 (TEM).
主要な成果:
- ポリディスパースSBSトライブロックコポリマーは,自己組織化して周期的なナノ構造を形成します.
- これらの構造は,単分散の対称と比較して,著しく安定性が向上しています.
- 完全な形態図が作成され,ナノスケールアセンブリが多分散性で達成可能であることを示しました.
結論:
- ブロックコポリマーにおける鎖の長さの異質性は,オーダーされたナノ構造物の形成を妨げるものではない.
- ポリディスパルセブロックコポリマーは,非常に安定した自己組み立て材料を形成することができます.
- 狭い分散は,ブロックコポリマーで定期的なナノスケールアセンブリを達成するための前提条件ではありません.
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