排名塑料聚合物加快气候变化的排名
Maryam Hoseini1,2, Jess Stead1, Tom Bond1
1School of Sustainability, Civil and Environmental Engineering, University of Surrey, Stag Hill, Guildford GU2 7XH, UK. t.bond@surrey.ac.uk.
Environmental science. Processes & impacts
|October 26, 2023
概括
聚烯 (PP) 在常见塑料中降解速度最快,与预期相反. 在气候变化期间监测碳基指数有助于预测聚合物碎片化,尽管在低氧环境中需要其他方法.
科学领域:
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
背景情况:
- 环境塑料降解的时间表在很大程度上是未知的.
- 了解聚合物降解对于环境影响评估至关重要.
研究的目的:
- 为了对五种常见塑料聚合物的环境降解速度进行排名:低密度聚乙烯 (LDPE),聚烯 (PP),聚烯 (PS),聚乳酸 (PLA) 和聚乙烯四甲酸 (PET).
- 为了研究物理化学性质和降解速率之间的相关性.
- 评估碳基指数监测对预测聚合物碎片化的有用性.
主要方法:
- 在41天内用于光化学降解的加速化室.
- 通过质量损失,碳烯指数,结晶度和接触角度监测降解.
- 测试了五种相同尺寸的塑料薄膜和一个聚乙烯搬运袋 (PEB).
主要成果:
- 质量损失排名:PP ≫ LDPE > PEB > PS > PLA > PET. 这是一个很好的排名.
- 估计的完全降解时间从0.27年 (PP) 到1179年 (PET).
- PP显示出意想不到的快速质量损失,可能是由于添加剂. 在PP和LDPE中,碳烯指数的增加更快.
结论:
- 聚烯 (PP) 的降解速度明显快于其他测试过的聚合物,这与现有的文献相反.
- 在加速气候变化期间监测碳烯指数是快速聚合物碎片化的有用指标.
- 需要进一步的研究来模拟光氧化有限的环境中的降解,例如深海.
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