有效交叉链密度作为复杂聚合物网络中结构-属性关系的指标:从烯酸胺系统的见解
Amirhossein Gooranorimi1, Seyyed Mohammad Mousavifard1, Mohsen Mohseni1
1Department of Polymer and Color Engineering, Amirkabir University of Technology, 424 Hafez Avenue, Tehran 15875-4413, Iran.
ACS applied polymer materials
|July 31, 2025
概括
一个新的度量,有效交叉链密度 (XLD extsuperscript{eff}),准确地预测了聚合物网络的特性. 这一进步有助于在体设计具有所需热力学特性的耐热聚合物.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 像交叉链密度 (XLD) 这样的传统指标难以捕捉聚合物网络的复杂性.
- 像功能组,连接点和缺陷等结构因素阻碍了准确的微观结构描述.
研究的目的:
- 开发一种更准确的指标来描述聚合物网络的微观结构.
- 建立聚合物微观结构和热力学特性之间的相关性.
- 引入有效的交叉链接密度 (XLD extsuperscript{eff}) 作为一个预测工具.
主要方法:
- 采用了多级分子动力学模拟.
- 构建了复杂的聚合物网络结构,包括烯酸-胺系统.
- 通过考虑每个交叉链的弹性贡献,开发了一种修改后的XLD度量,XLD extsuperscript{eff}.
主要成果:
- 在XLD extsuperscript{eff} 和弹性模量之间发现了强烈的线性相关性.
- 在XLD extsuperscript{eff}和玻璃过渡温度 (T extsubscript{g}) 之间观察到强烈的线性相关性.
- 传统的XLD无法建立这些强大的相关性.
结论:
- XLD extsuperscript{eff} 是热力学性质的强大和可预测度量.
- 这一指标在各种交叉链接转换和预聚合物系统中有效.
- XLD extsuperscript{eff} 促进了热聚合物的设计和优化.
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