塑形记忆性能和PLA/PEG混合物的微结构演变:塑化剂含量和分子重量的作用
Jiradet Sringam1,2, Todsapol Kajornprai1,2, Tatiya Trongsatitkul1,2
1School of Polymer Engineering, Institute of Engineering, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand.
Polymers
|January 25, 2025
概括
聚乳酸 (PLA) 被修改为聚乙烯糖醇 (PEG) 以改善其形状记忆特性. 最佳的混合物表现出极好的形状固定性和恢复性,使其适合医疗应用.
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
- 生物材料工程 生物材料工程
背景情况:
- 聚乳酸 (PLA) 具有形状记忆能力,但受到脆性和高玻璃过渡温度 (T) 的限制.
- 提高PLA的灵活性和耐用性对于先进的应用,特别是医疗领域至关重要.
研究的目的:
- 通过添加聚乙烯甘醇 (PEG) 来研究PLA形状记忆性质的修改.
- 优化PEG含量和分子量,以提高PLA/PEG混合物的性能.
- 评估这些混合物适用于医疗片等应用的适用性.
主要方法:
- 差分扫描热量计 (DSC) 用于分析热性质和机制.
- 协同广角X射线散射 (WAXS) 在形状记忆循环过程中研究微观结构的演变.
- 机械测试用于评估弹性和强度的变化.
主要成果:
- 一种含有15%重量的PEG (12,000 g/mol) 的PLA/PEG混合物在特定温度下显示出优异的形状固定性 (99.27%) 和回收率 (95.77%).
- 结合PEG降低了Tg,增加了结晶性,增强了链的流动性,促进了形状记忆行为.
- 微观结构分析显示,在拉伸过程中引起应变的链条对齐,并在恢复过程中产生同位素放松.
- 机械测试表明,破裂时延伸和冲击强度有所改善,PEG含量和分子量增加.
结论:
- PLA/PEG混合物提供了可调整的形状记忆性能和机械性能平衡.
- 最佳的混合物 (15%PEG,12000g/mol) 是可定制,可生物降解的医疗器械的有希望的候选者.
- 了解热和微结构变化是优化形状记忆聚合物的关键.
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