持久性和热触发的塑化在聚乙烯氧化物修饰的聚乙烯氧化物) -块-聚乙烯氧化物) 中
Jonathan P Coote1, Matthew C Larson1, Frank S Bates1
1Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States.
ACS macro letters
|January 2, 2025
概括
将聚乙烯氧化物-块聚乙烯氧化物添加到聚乳化物中,提高了性,加速了降解. 这种混合物保持了包装的耐用性,并在加热时降解得更快.
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
- 可持续材料 可持续材料
背景情况:
- 聚乳酸 (PLA) 是一种适用于一次性使用包装的可生物降解聚合物.
- 在典型条件下,PLA的应用受到脆性和缓慢降解的限制.
- 高玻璃过渡温度 (Tg) 的PLA限制其生物降解性,以工业堆肥.
研究的目的:
- 为了提高聚乳酸的性和生物降解性.
- 研究聚乙烯氧化物-块聚乙烯氧化物 (PEO-PBO) 对PLA特性的影响.
- 评估PEO-PBO/PLA混合物的长期稳定性和寿命末退化情况.
主要方法:
- 与5%重量的聚乙烯氧化物-块聚乙烯氧化物 (PEO-PBO) 混合聚乙烯乳化物.
- 在9个月内评估混合性和形态.
- 在热和暴露于人造海水中高温后研究降解动力学.
主要成果:
- 添加PEO-PBO显著提高了PLA的性,维持了九个多月.
- 氧化降解PEO-PBO形成的寡合体被限制在PLA的玻璃基质内.
- 热诱导PEO-PBO降解产品迁移,塑化PLA和降低Tg.
- 陈旧的PEO-PBO/PLA混合物在50°C下降解的速度几乎是纯PLA的两倍.
结论:
- PEO-PBO充当双重功能添加剂,在使用过程中增强PLA的性,并在使用后加速降解.
- 用PEO-PBO降解产品对PLA的热触发塑化有助于更快的生物降解.
- 这种方法解决了PLA在可持续包装应用中的关键局限性.
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