通过高热循环对聚酸酸盐的结晶动力学的研究
Anindita Mondol1,2, Jun Wang3, Farhad Ein-Mozaffari1
1Chemical Engineering Department, Toronto Metropolitan University, Toronto, ON M5B 2K3, Canada.
ACS polymers Au
|August 18, 2025
概括
像PHB和PHBV这样的多基酸盐 (PHAs) 在高冷却速度下显示出减少的结晶性. 它们的结晶行为对加工条件敏感,影响了可持续的聚合物应用.
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
- 可持续的高分子.
背景情况:
- 聚酸酸 (PHAs) 是可持续的,可生物降解的聚合物,有可能取代传统的塑料.
- PHAs用于包装,农业,化品和生物医学领域.
- 了解PHA结晶对于优化其制造和应用至关重要.
研究的目的:
- 研究聚基酸盐 (PHB) 和聚基酸盐-co-3-hydroxyvalerate (PHBV) 的异热和非异热结晶行为.
- 分析受控的高热循环和冷却速度对PHA结晶动态的影响.
- 评估PHA结晶的常见建模技术的预测能力.
主要方法:
- 利用受控的高热循环进行异热和非异热结晶研究.
- 在500°C/分钟进行快速超冷,以隔离结晶动力学.
- 在高达500°C/分钟的冷却速度下检查结晶行为,以模拟工业加工.
主要成果:
- 同热激活能为PHB的91kJ/mol,而PHBV的139kJ/mol.
- 非异热结晶显著下降,随着PHB和PHBV的冷却速度的增加.
- 在高冷却速度下,PHB晶度从48.6%降至10.9%,PHBV从45.9%降至接近零.
- 常见的结晶模型显示基于同热数据的非同热动力学的预测能力有限.
结论:
- PHA结晶对加工条件,特别是冷却速度非常敏感.
- 目前的建模方法在预测非异热PHA结晶方面存在局限性.
- 提供了对PHA结晶机制的新见解,对于优化可持续聚合物制造至关重要.
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