聚胺混合物的结晶和性能,包括聚胺4,聚胺6及其共聚物
Yajing Zhang1,2, Mingda Wang1,2, Di Zhang1,2
1State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
Polymers
|August 26, 2023
概括
聚胺4 (PA4) 与聚胺6 (PA6) 的混合物是为了改善炼加工而开发的. 将PA4与PA6和可聚胺4/6 (R46) 混合使得可控的结晶和增强的机械性能.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- 聚胺4 (PA4) 是一种生物基和可生物降解的聚合物.
- 在PA4中,高键密度导致其分解温度附近的高点,阻碍了处理.
- 开发可加工的PA4基材料对于可持续应用至关重要.
研究的目的:
- 研究混合聚胺4 (PA4) 与聚胺6 (PA6) 和聚胺4/6 (R46) 的混合对混合结晶行为的影响.
- 了解PA4/PA6和PA4/PA6/R46混合物的相分离和结晶机制.
- 为了将混合物成分与热稳定性,结晶性和机械性能相关联.
主要方法:
- 制备二进制PA4/PA6 (B46) 和三进制PA4/PA6/R46 (B46/R46) 的混合物.
- 使用差分扫描热度计 (DSC) 和X射线衍射 (XRD) 等技术分析结晶行为的分析.
- 模拟分子动力学以研究分子链的方向.
主要成果:
- PA4/PA6和PA4/PA6/R46混合物表现出结晶诱导的相分离,形成富含PA4和富含PA6的结晶相.
- B46混合物中PA6含量的增加影响了热稳定性和结晶性,PA6对富含PA4的相结晶的贡献减少.
- 与二进制B46混合物相比,三进制B46/R46混合物显示出较低的点,结晶度和粒度.
结论:
- 将PA4与PA6和R46混合为修改结晶行为和提高可加工性提供了一种可行的策略.
- PA4和PA6相之间的相互作用影响了核和结晶动力学.
- 含有30-40%PA6的PA4/PA6混合物表现出最佳的机械性能,突出了它们对先进材料应用的潜力.
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