l-Poly (乳酸),d-Poly (乳酸),它们的混合物和立体复合PLA片的堆肥性能
James F Macnamara1, Anibal Bher1, Rafael Auras1
1School of Packaging, Michigan State University, East Lansing, Michigan 48824-1223, United States.
ACS omega
|May 19, 2025
概括
可生物降解的聚乳酸 (PLA) 薄膜在减少塑料垃圾方面表现有前途. 立体复合PLA在堆肥中实现了97%的生物降解,为传统塑料提供了可持续的替代品.
科学领域:
- 聚合物科学 聚合物科学
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
背景情况:
- 一次性塑料在全球塑料垃圾中发挥了重要作用.
- 可生物降解的聚合物,特别是聚乳酸 (PLA),提供了潜在的解决方案.
- 需要进行研究来评估不同形式的PLA的生物降解性.
研究的目的:
- 评估堆肥中各种聚乳酸 (PLA) 形式的生物降解.
- 为了比较l-poly ((乳酸) (PLLA),d-poly ((乳酸) (PDLA),PLLA/PDLA混合物和冷凝立体复合PLA (sc-PLLA/PDLA-50-50-A) 的降解速度.
- 研究生物降解过程中结晶性和分子量变化的影响.
主要方法:
- 用实验室规模的直接测量呼吸计来模拟堆肥条件.
- 在120天的时间内,评估了PLA薄膜的非生物和生物降解.
- 使用扫描电子显微镜 (SEM) 可视化薄膜侵蚀.
主要成果:
- 在降解过程中,PLA薄膜的结晶性最初会增加.
- 由于水解和随后的生物降解,分子重量减少.
- 烧焦的sc-PLLA/PDLA-50-50-A显示了最高的生物降解 (97%),其次是PLLA/PDLA 50-50混合物 (86%). 在PDLA中,生物降解率最低 (40%).
- SEM证实了PLA膜的逐渐侵蚀.
结论:
- 立体复合PLA显示出作为传统塑料的可生物降解替代品的巨大潜力.
- 优化的PLA配方,如化立体复合PLA,可以实现高生物降解率.
- 这些发现支持PLA的发展,作为石化塑料的可持续替代品.
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