水素結合とポリ (アルキルアクリラミド) の構成
Dorothy M Duffy1, P Mark Rodger
1Department of Chemistry, University of Warwick, Coventry, CV4 7AL, United Kingdom. d.duffy@ucl.ac.uk
Journal of the American Chemical Society
|May 2, 2002
まとめ
非極性溶媒におけるポリマー構成をシミュレートした. 特定の骨幹構造は安定した水素結合を形成し,ポリマーの崩壊とサイドチェーン障害に影響を与え,結晶化に影響を与えます.
科学分野:
- ポリマーサイエンスの科学
- コンピューティング・ケミストリー
- マテリアルサイエンス 材料科学
背景:
- ポリマーの形状を理解することは,材料の性質を予測するために非常に重要です.
- ポリー ((アルキルアクリルアミド) は溶液中に複雑な行動を示します.
- 溶媒の極性は,ポリマー鎖の組織に大きな影響を与えます.
研究 の 目的:
- ポリ (アルキルアクリラミド) オリゴマーの溶液構成を調べる.
- 特定の骨幹構造と水素結合の役割を明らかにする.
- ポリマーの崩壊とサイドチェーンのオーダーリングへの影響を理解するために.
主な方法:
- 分子動力学シミュレーションが採用されました.
- トルション配列と分子内水素結合の分析.
- 構築されたオリゴーマー構成のエネルギー最小化.
主要な成果:
- ポリ・メチル・アクリラミドは低温で崩壊し,ポリ・オクタデシル・アクリラミドの崩壊は,容積効果が除外されたことで抑制される.
- 強い分子内水素結合を持つ安定したトランス-左側-トランス-左側-トランス脊椎形状が特定されました.
- この安定した形状は,全トランス構造と螺旋構造と比較して,最小化されたエネルギーが低いことを示した.
- ポリ ((オクタデシルアクリラミド) の水素結合は,結晶化を阻害するサイドチェーン障害を誘発した.
結論:
- 特定の骨幹構造が,非極性溶剤のポリ (アルキルアクリルアミド) 形状と安定性を決定する.
- 分子内水素結合は,ポリマーの行動とエネルギーに重要な役割を果たします.
- 水素結合によるサイドチェーン障害は,結晶化と表軸のシードの可能性を制限する.
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