在环境因素的相互作用下,可降解塑料聚乳酸的老化行为
Hui Jiang1,2, Yiqun Wang1,2, Jiaoxia Sun1,2
1Key Laboratory of Hydraulic and Waterway Engineering of the Ministry of Education, School of River and Ocean Engineering, Chongqing Jiaotong University, Chongqing, 400074, China.
Environmental geochemistry and health
|April 9, 2024
概括
像聚乳酸 (PLA) 这样的可生物降解塑料会降解并释放微塑料. 湿度显著影响PLA老化,影响其性能,并可能将有害的微塑料释放到环境中.
科学领域:
- 材料科学 材料科学 材料科学
- 环境科学 环境科学
- 聚合物化学 聚合物化学
背景情况:
- 可生物降解的塑料,如聚乳酸 (PLA),越来越多地被用作传统塑料的替代品.
- 这些材料的老化可能会导致微塑料的浸出,造成环境风险.
- 了解退化途径和影响因素对于评估它们对环境的影响至关重要.
研究的目的:
- 在各种环境条件下研究聚乳酸 (PLA) 的老化特性.
- 为了确定温度,光线和湿度对PLA降解的影响.
- 阐明与PLA老化相关的化学和物理变化.
主要方法:
- 响应表面方法 (RSM) 用于研究温度,光线和湿度的影响.
- 分析包括X射线光电子光谱 (XPS) 检测化学变化 (C/O比率,功能组).
- 评估了结晶性,表面地形和机械性能 (拉伸强度,延伸).
主要成果:
- 湿度对PLA老化产生了最显著的影响,其次是光和温度.
- 温度-光和湿度-阳光之间的相互作用显著影响了PLA老化.
- XPS揭示了键裂变 (O-C=O) 和C=O和C-O组的形成.
- 衰老导致表面形态变化,结晶性增加,拉伸强度和延长性降低.
结论:
- 环境因素,特别是湿度,显著影响聚乳酸的老化.
- PLA老化涉及化学修饰和结构变化,导致机械性能降低.
- 这些发现为可生物降解塑料的环境老化行为提供了关键的见解.
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