超强硬PLLA/TPE/EMA-GMA三级混合物的相位形态和机械性能
Martin Boruvka1, Roman Base1, Jan Novak1
1Department of Engineering Technology, Faculty of Mechanical Engineering, Technical University of Liberec, Studenstka 2, 461 17 Liberec, Czech Republic.
Polymers
|January 23, 2024
概括
研究人员通过将其与热塑性聚弹性体 (TPE) 和兼容剂混合,提高了易碎的聚乳酸 (PLA) 的性. 这大大提高了对更广泛应用的冲击强度和柔性.
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
- 材料工程 材料工程 材料工程
背景情况:
- 聚乳酸 (PLA) 具有固有的脆性,限制其在需要高变形的应用中使用.
- 提高PLA的冲击强度和柔性对于扩大其应用范围至关重要.
研究的目的:
- 增强机械性能,特别是聚乳酸 (PLA) 的冲击强度和柔性.
- 通过使用兼容剂,研究聚乳酸 (PLLA) /热塑性聚弹性体 (TPE) 混合物的硬化机制.
主要方法:
- 化混合被用来制备PLLA,TPE和乙烯基甲基酸盐-甘油甲基酸盐 (EMA-GMA) 共聚物的二元和三元混合物.
- 差分扫描热量计 (DSC) 用于分析热行为,结晶性和可混合性.
- 进行了拉伸试验和划痕冲击试验,以评估不同温度下的机械性能.
主要成果:
- 与EMA-GMA的兼容性诱导了PLLA/TPE混合物中的脆性-柔性过渡,使破裂时的延长增加到227%.
- 三级混合物表现出"超强硬"的行为,具有高口冲击强度 (在23°C时为89.2kJ·m-2).
- 在零度以下温度 (-40°C) 观察到裂纹启动电阻的显著改善,冲击强度达到178.1kJ·m−2.
结论:
- EMA-GMA兼容器有效地改善了接口粘附性,并促进了涉及解腔和矩阵剪切屈服的硬化机制.
- 该研究表明,在实现超强度方面,形态变化 (海岛变为连续性) 和界面特性之间存在协同效应.
- 开发的PLLA/TPE/EMA-GMA混合物为需要增强性和抗冲击的PLA材料的应用提供了有前途的解决方案.
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