高分子量ブロックコポリマーの合成と,固体状態で秩序ある形状に組み立てられる
1Department of Chemistry, 423K Chemistry Building, University of Iowa, Iowa City, Iowa 52242, USA.
Journal of the American Chemical Society
|August 10, 2007
まとめ
研究者らは,高分子量コンブブロックコポリマーを合成し,添加物なしで200nm以上のオーダーされた構造を達成しました. これらの新しいポリマーアーキテクチャは,自己組み立て材料の新たな可能性を提供します.
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:
- ブロックコポリマーは,秩序あるナノ構造体への自己組み立てに不可欠です.
- オーダーされたポリマー形態学で大きなドメインサイズ (>100 nm) を達成するには,通常添加物が必要です.
- ポリマーアーキテクチャの制御は,自己組立特性を調節する鍵です.
研究 の 目的:
- 高分子量コンブブロックコポリマーのための単純な合成を開発する.
- これらの新しいポリマーの固体状態の自己組み立てを,秩序付けられた形態学に調査するために.
- ブロックコポリマーと線形ブロックコポリマーの組立行動を比較する.
主な方法:
- リング開きメタテシスポリメリゼーションと原子移転ラジカルポリメリゼーションを用いた2段階の合成.
- 低ポリ分散性を保証する技術を用いたポリマーの特徴化.
- 溶媒の蒸発と熱アニリングによって誘発された固体組成.
- 電子スキャニングと光学顕微鏡を用いた形状分析.
主要な成果:
- 分子重量>1,000,000 g/molのコンブロックコポリマーの合成に成功しました.
- ドメインサイズが132から258 nmの範囲で,添加物なしで,オーダーされた形態 (球形,ラメラ,円筒形) を形成する.
- 組み立てられた材料による光の反射の実証,溶媒の膨張によって調整可能.
結論:
- コンブブロックコポリマーは,添加物なしで固体状態で大領域のオーダーされた形態学を達成することができます.
- この研究は,固体組み立てに適したポリマー構造と分子重量の範囲を広げています.
- この発見は,調整可能なナノスケール構造を持つ高度な材料を作成するための新しいプラットフォームを提供します.
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