聚乳酸的光降解:玻璃化和融化行为的特征作为分子重量的函数
Ábris Dávid Virág1, Csenge Tóth1, Kolos Molnár2
1Department of Polymer Engineering, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3. H-1111 Budapest, Hungary.
International journal of biological macromolecules
|August 16, 2023
概括
暴露在UV-C光下的聚乳酸 (PLA) 呈现出降解,影响其性能. 这项研究确定了PLA薄膜13个灭菌周期的限制,以保持机械完整性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 摄影化学的使用.
背景情况:
- 在COVID-19大流行期间,UV-C杀菌灯的广泛使用增加了家庭应用.
- 对于UV-C辐射对聚乳酸 (PLA) 机械和质性质的长期影响的了解有限.
- 紫外线诱导的降解和分子结构的变化与PLA的宏观性质之间的相关性仍然不清楚.
研究的目的:
- 调查长时间暴露于UV-C辐射对聚乳酸 (PLA) 机械和质性质的影响.
- 为了将观察到的降解效应与分子结构变化相关联.
- 制定安全使用PLA材料UV-C灭菌的指导方针.
主要方法:
- 凝透色谱 (GPC) 用于分析分子重量变化.
- 里埃变换红外光谱 (FTIR) 和UV-Vis光谱用于评估化学结构的变化.
- 热分析,风学测试和拉力测试,以评估机械和融性能.
主要成果:
- 紫外线辐射诱导了PLA的化学结构变化,导致分子重量的改变.
- 通过热性,性和抗拉性质的变化量化降解,测试结果适用于估计分子质量损失.
- 开发了一个3D辐射图,以帮助设计UV-C消毒装置.
结论:
- 该研究提供了对PLA中UV-C降解的分子层次理解.
- 建议对测试的PLA薄膜进行最多13个灭菌周期,以避免拉伸强度和模量发生显著变化.
- 这些发现为在使用PLA材料的环境中应用UV-C杀菌提供了实际指导.
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