特定のモノマー-モノマー相互作用のない合成ポリマーの多鎖ヘリックスにおける分子量認識
Jiro Kumaki1, Takehiro Kawauchi, Koichi Ute
1Japan Science and Technology Agency (JST), Department of Chemical Science and Technology, Faculty and School of Engineering, Japan. kumaki@yz.yamagata-u.ac.jp
Journal of the American Chemical Society
|May 1, 2008
まとめ
ステレオ複合体であるポリ (メチルメタクリlate) は三連鎖ヘリクスを形成する. 分子長がヘリックス長を決定し,分子重量の認識は,特定の相互作用ではなく,トポロジカルヘリックス構造を通じて起こります.
科学分野:
- ポリマーサイエンスの科学
- 超分子化学 超分子化学
- マテリアルサイエンス 材料科学
背景:
- ステレオレギュラーイソタクティックおよびシンディオタクティックポリ (イット-PMMAとst-PMMA) は,ヴァン・デル・ワールスの相互作用によってステレオ複合体 (SC) を形成する.
- SC形成は,コモディティポリマーの螺旋状上分子構造の希少な例です.
研究 の 目的:
- 異なる分子量と分布を持つ均一なit-およびst-PMMAによって形成されるSCの詳細な構造を調査する.
- 分子重量とその分布がSC構造に与える影響を判断する.
主な方法:
- 狭い分子量分布の均一なit-およびst-PMMAを使用したSCの製造.
- 高解像度原子力顕微鏡 (AFM) でSC構造を分析する.
主要な成果:
- 補完的なit-およびst-PMMAのより長い分子鎖が,SCの全長を決定する.
- より短いポリマー鎖は,より長い鎖を補完または覆うために結合します.
- 観測結果は,三連鎖の螺旋構造モデル (st-PMMAヘリックス内の2つのit-PMMAチェーン) を支持しています.
- IT-PMMAヘリックス形成における,実証された分子量認識 ("分子分類")
結論:
- 三連鎖螺旋モデルは,分子重量の広い範囲のSCに適用できます.
- 分子重量の認識は,特定のモノメアの相互作用から独立して,ヴァン・デル・ワールス力によって駆動されるトポロジカルヘリケール構造によって達成可能である.
関連する概念動画
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