聚胺4和不同生物基聚胺混合物的分子动力学模拟和非异热结晶动力学
Yajing Zhang1,2, Mingda Wang1,2, Liquan Wang3
1State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China. zhaoliming@ecust.edu.cn.
Physical chemistry chemical physics : PCCP
|September 13, 2023
概括
混合率显著影响聚胺4 (PA4) 混合物的结晶. 在PA4/PA56混合物中含有较高的聚胺56 (PA56) 含量会降低结晶性,而聚胺11 (PA11) 在PA4结晶中所参与的最小.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 结晶运动学 结晶运动学
背景情况:
- 聚胺混合物为各种应用提供可调节的性能.
- 了解结晶行为对于材料性能至关重要.
- 聚胺4 (PA4) 与PA56和PA11的混合物具有独特的结构和加工特性.
研究的目的:
- 研究结构单位和混合比对PA4/PA56和PA4/PA11混合物的结晶行为的影响.
- 阐明分子结构,相分离和结晶动力学之间的相互作用.
- 为设计具有定制性质的PA4基聚胺混合物提供理论基础.
主要方法:
- 分子动力学模拟以模拟混合行为.
- 非异热结晶动力学分析.
- 混合物形态和结晶性的实验性表征.
主要成果:
- PA4/PA56 (B4/56) 混合物显示晶度降低,PA56含量增加 (30-50%),这是由于PA56进入了富含PA4的阶段.
- 随着PA11含量的增加,PA4/PA11 (B4/11) 混合物表现出降低的结晶性,PA11在PA4结晶中的参与最小.
- 在两种混合物中都观察到结晶诱导的相分离,在B4/56.6中PA56含量较高时变得更加明显.
- 含有更高PA4含量的B4/56更容易结晶,而B4/11在活性能量更高的情况下显示出更差的结晶能力.
结论:
- 混合率显著影响PA4基混合物的结晶行为和相分离.
- PA56的结合会影响PA4的结晶,而PA11的相互作用有限.
- 这些发现为控制特定应用的聚胺混合物的形态和特性提供了洞察力.
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