结合和多 (基烯胺) 的结构
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
概括
模拟了非极性溶剂中的聚合物构成. 特定的骨干结构形成稳定的键,影响聚合物崩和侧链障碍,影响结晶.
科学领域:
- 聚合物科学 聚合物科学
- 计算化学计算化学
- 材料科学 材料科学 材料科学
背景情况:
- 了解聚合物构造对于预测材料特性至关重要.
- 聚甲基烯胺在溶液中表现出复杂的行为.
- 溶剂极性显著影响聚合物链组织.
研究的目的:
- 为了研究聚乙烯胺) 寡合体的溶液构造.
- 阐明特定的骨干结构和键的作用.
- 了解对聚合物崩和侧链排序的影响.
主要方法:
- 使用了分子动力学模拟.
- 扭曲序列和分子内键的分析.
- 构建的寡合体构造的能量最小化.
主要成果:
- 聚甲基烯胺) 在低温下崩;聚八甲基烯胺) 的崩被排除的体积效应所抑制.
- 确定了一种稳定的跨左转-跨左转-跨左转的脊柱形状,具有强大的分子内键.
- 这种稳定的构造与全跨和螺旋结构相比,显示出较低的最小化能量.
- 在poly ((octadecyl acrylamide) 中的结合诱导了侧链障碍,阻碍了结晶.
结论:
- 特定的骨干结构决定了多 (基烯胺) 形状和稳定性在非极性溶剂中.
- 分子内键在聚合物行为和能量中起着关键作用.
- 由于结合造成的侧链障碍限制了结晶和表轴播种的潜力.
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