塑化/化对聚乳酸的热,动力,机械和风学性能的影响
Lina Benkraled1, Assia Zennaki1, Latifa Zair1
1Laboratoire de Recherche sur les Macromolécules (LRM), Faculté des Sciences, Université Abou Bekr Belkaïd, BP 119, Tlemcen 13000, Algeria.
Polymers
|April 13, 2024
概括
这项研究表明,聚乙烯甘醇 (PEG) 增塑剂改善了聚乳酸 (PLA) 薄膜的性能. 添加PEG可以增强结晶性并改变晶体形状,但高度会导致相分离.
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
- 生物材料工程 生物材料工程
背景情况:
- 聚乳酸 (PLA) 是一种可生物降解的聚合物,具有有前途的应用,但通常需要修改以增强其性能.
- 塑化剂通常用于提高像PLA这样的聚合物的灵活性和可加工性.
- 低分子量聚乙烯甘醇 (PEG) 是塑化PLA的潜在候选者,因为它具有兼容性和生物降解性.
研究的目的:
- 研究低分子量聚乙烯甘醇 (PEG) 作为增塑剂对聚乳酸 (PLA) 的热和机械性能的影响.
- 为了确定PLA/PEG混合物在各种成分中的可混合性和相位行为.
- 分析PEG对PLA晶体结构和回火行为的影响.
主要方法:
- 使用溶剂造方法制备PLA/PEG混合膜.
- 使用差分扫描热量计 (DSC) 分析热性质.
- 通过动态机械分析 (DMA) 和动态学分析评估机械性能.
主要成果:
- 增加PEG含量高达20%的重量,降低了玻璃过渡和冷结晶温度,同时增加了结晶性和结晶率.
- PLA/PEG混合物可混合至20%的PEG重量;相位分离发生在30%的PEG重量.
- 添加PEG改变了晶体形式 (α'和α),并在回火时有利于两者的混合,增加了整体结晶性.
结论:
- 低分子量PEG有效地塑化了PLA,提高了其可加工性并修改了其热和机械特性.
- 酸/PEG混合物的混合度窗口高达20%的PEG重量,超过此,相位分离会影响性能.
- PEG影响PLA的结晶动力学和形态学,在化过程中促进特定的晶体形式,这可以用于量身定制的材料特性.
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