环保金属有机框架作为聚 (乳酸) 的核化剂
Safaa H El-Taweel1, Safaa S Hassan2, Khaled M Ismail2
1Chemistry Department, Faculty of Science, Cairo University, Orman, Giza 12613, Egypt; Engineering and Materials Science Department, German University in Cairo, New Cairo City, Egypt.
International journal of biological macromolecules
|May 29, 2024
概括
添加基于的金属有机框架 (Zn-MOF) 颗粒显著加快了环保的聚-乳酸 (PLA) 的结晶. 这增强了PLA的性能.
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
- 纳米技术纳米技术
背景情况:
- 聚L-乳酸 (PLA) 是一种环保的生物聚合物,具有越来越多的应用.
- 提高PLA的多功能性和加工特性对于更广泛的采用至关重要.
- 金属有机框架 (MOF) 为材料修改提供可调节的特性.
研究的目的:
- 研究基于的金属有机框架 (Zn-MOF) 颗粒对PLA非同热结晶行为的影响.
- 评估Zn-MOF作为可生物降解PLA的核化剂.
- 分析PLA-Zn-MOF复合材料的结晶动力学和热性能.
主要方法:
- 差分扫描热度计 (DSC) 用于非异热结晶分析.
- 修改了Avrami和Mo模型用于结晶动力学.
- 弗里德曼同转换动力学方法用于有效的激活能量的确定.
- 极化光学显微镜 (POM) 和扫描电子显微镜 (SEM) 用于形态分析.
主要成果:
- Zn-MOF显著加快了PLA结晶,使结晶时间减少了一半,并增加了结晶速率常数.
- 化结晶温度的PLA-Zn-MOF复合材料增加了多达21°C.
- 有效激活能量 (∆E) 值随着Zn-MOF含量增加而下降.
- 在POM中,PLA-Zn-MOF复合材料中发现了更高的核密度和更小的球状石尺寸.
- SEM证实了PLA矩阵内Zn-MOF的良好分散.
结论:
- -MOF作为PLA的有效核化剂,增强融结晶温度,核化密度和结晶性.
- 添加Zn-MOF会降低PLA的有效激活能量和球形状的尺寸.
- 在不改变晶体结构的情况下,PLA-Zn-MOF复合材料表现出更好的性能.
- 已确定有效核化的最佳Zn-MOF度 (0.7-1.0 wt%).
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