自组装核剂对多样乳酸的结晶行为和球状形态学的作用
Zhixiang Yan1, Yanqin Huang2, Wenfeng Zhao2
1Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
ACS omega
|November 29, 2023
概括
脱酸二甲基化物 (DDBH) 显著增强了多乳酸 (PLA) 结晶. 添加DDBH可以改善PLA.
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
- 结晶工程 结晶工程
背景情况:
- 聚乳酸 (PLA) 是一种具有有限耐热性的可生物降解聚合物.
- 改善PLA的结晶行为对于扩大其应用至关重要.
- 核剂可以改变聚合物结晶动力学和形态学.
研究的目的:
- 为了研究二乙烯酸二甲基化物 (DDBH) 作为聚乳酸 (PLA) 的核化剂.
- 了解DDBH度对PLA结晶和形态学的影响.
- 评估DDBH对PLA热性质的影响.
主要方法:
- 在PLA化物中对DDBH组件进行系统调查.
- 同热结晶研究. 同热结晶研究.
- 不同扫描热量计 (DSC) 分析.
- 在现场广角X射线衍射 (WAXD) 分析.
主要成果:
- DDBH (0.5-0.9重量%) 形成了类似树的结构,改变了PLA的形态从球形到树形.
- 增强了PLA结晶性和结晶率,半结晶时间从6.12分钟减少到0.28分钟,温度为120°C,重量为0.9%DDBH.
- 结晶度和叶片厚度增加,而微结晶大小随着DDBH含量增加而减少.
- 增加了PLA/DDBH混合物的热偏移温度,提高了耐热性.
结论:
- DDBH有效地作为PLA的核化剂,促进了快速结晶.
- 添加DDBH显著提高了PLA的热性能和耐热性.
- 在各种应用中,DDBH显示了提高PLA性能的潜力.
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