聚乳酸的链异质性及其对结晶动态的影响
Tao Yang1, Shuang He1, Peng Liu1
1College of Chemical Engineering and Material Science, Tianjin University of Science and Technology, Tianjin 300457, PR China.
International journal of biological macromolecules
|July 24, 2024
概括
可生物降解的聚乳酸 (PLA) 通过温度上升的化分化 (TREF) 分化,揭示了链微观结构和特性之间的强烈联系. 较高的化温度与增加的立体规律性,结晶率和层厚度相关.
科学领域:
- 聚合物科学与工程 聚合物科学与工程
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 聚乳酸 (PLA) 是一种具有重要的工业应用的可生物降解聚合物.
- 了解PLA的微观结构及其特性之间的关系对于优化其性能至关重要.
- 分割技术对于隔离具有特定特性的聚合物链至关重要.
研究的目的:
- 使用温度上升的化分化 (TREF) 将聚乳酸 (PLA) 树脂分离成不同的分量.
- 建立PLA分量的链微结构及其由此产生的特性之间的全面关系.
- 研究PLA分量的非同热结晶动力学和非同热冷结晶动力学.
主要方法:
- 使用温度升高电解分解法 (TREF) 将PLA分成十个不同的分数.
- 使用了连续的自我核化/化 (SSA) 热分化,凝浸透色谱 (GPC),差异扫描热量计 (DSC) 和13C核磁共振 (13C NMR) 光谱.
- 使用选择的PLA分数研究了非异热结晶动力学和非异热冷结晶动力学.
主要成果:
- PLA成功地分成十个部分,其中很大一部分在100,110,114和118°C时化.
- -莫方法被证明适用于分析PLA的非同热结晶和冷结晶动力学.
- 在升高的化温度和增强的立体规律性,结晶率,结晶能力和PLA碎片的层状厚度之间观察到正相关性.
结论:
- 该研究成功地确定了PLA受TREF影响的链微结构及其宏观性质之间的联系.
- 这些发现为进一步对PLA进行基础研究提供了基础.
- 这项研究对基于PLA的材料的工业应用和优化有影响.
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