从典型的聚乙烯化物产品中,室温释放短链和中链化
Haoran Yu1, Xing Liu2, Faqiang Zhan3
1Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Journal of hazardous materials
|July 1, 2025
概括
短链和中链化 (CPs) 在环境温度下从PVC产品中释放出来. SCCP迅速下降,而MCCP的释放速度较慢,影响了排放库存.
科学领域:
- 环境化学环境化学
- 聚合物科学 聚合物科学
- 毒理学 毒理学 毒理学
背景情况:
- 甲 (CPs) 是广泛产生的持久性有机污染物 (POPs).
- 消费品是大气中CP的重要来源,但环境释放数据很少.
- 在室温下测量CP的释放具有测量挑战.
研究的目的:
- 从PVC产品中量化短链 (SCCPs) 和中链 (MCCPs) CPs的室温释放率.
- 为了研究单个CP原体的释放动力学和机制.
- 开发时间变量的排放因子,以便更准确的CP排放清单.
主要方法:
- 从四种PVC产品在环境温度下的SCCP和MCCP释放率的量化.
- 应用一种特定于同源的量化方法.
- 使用机械发射模型研究释放动力学.
主要成果:
- SCCP和MCCP的释放率分别为0.0084-0.74μg/m2·min和0.003-0.17μg/m2·min. 这两种蛋白质的释放率分别为0.0084-0.74μg/m2·min和0.003-0.17μg/m2·min.
- 早期释放由表面挥发主导,随着时间的推移转向内部扩散.
- 在0.48-2.2年内,SCCP的释放率下降了一半,而MCCP的释放率缓慢下降.
结论:
- 已经描述了PVC产品中CP的环境温度释放率和动力学.
- SCCP和MCCP的独特释放模式对长期环境暴露有影响.
- 这些发现支持对CP进行改进的排放库存的开发.
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