溶剂中的聚乙烯小微和纳米塑料的隐形形式:分子振动的变化
Julie R Peller1, Noah Durlam1, Yanni Flaherty1
1Department of Chemistry, 1710 Chapel Drive, Valparaiso University, Valparaiso, IN 46383, USA.
The Science of the total environment
|February 22, 2025
概括
纳米塑料 (NP) 和小微塑料 (<10微米) 暴露于溶剂时会改变结构,影响其检测. 这些纳米污染物无处不在,影响生态系统和生物.
科学领域:
- 环境科学 环境科学
- 聚合物科学 聚合物科学
- 分析化学 分析化学
背景情况:
- 纳米塑料 (NP) 是1nm到1μm的塑料颗粒,在环境中无处不在.
- NP的形成是通过材料磨损,暴露在光线和塑料的正常使用而发生的.
- NP和小微塑料 (<10微米) 行为像溶剂中的体颗粒,不同于较大的塑料碎片.
研究的目的:
- 在水和有机溶剂中生成和表征聚乙烯 (PE) 小微塑料和纳米塑料溶液 (sM&NP).
- 用各种分析技术研究PE sM&NP中的分子和形态变化.
- 评估溶剂暴露对PE sM&NP的检测性和行为的影响.
主要方法:
- 在水和有机溶剂中生成PEsM&NP溶液,使用标准混合和新型溶解方法.
- 使用拉曼光谱,显微镜,传输电子显微镜 (TEM) 和动态光散射 (DLS) 的表征.
主要成果:
- 拉曼光谱检测显示,与固体PE相比,PE sM&NP的光谱变化显著,表明了分子和形态变化.
- 在有机溶剂中,PE sM&NP显示了聚合物结晶性的损失.
- 在水溶液中,PE sM&NP表现出更大的分子重组,在TEM下呈现无形,厚度不同.
- 结构性变化使PE sM&NP在现实世界水系统中难以检测.
结论:
- 暴露于溶剂显著改变了溶解纳米塑料和小微塑料的结构.
- 这些结构变化会影响它们与环境的相互作用,特别是在水系统中.
- 在环境样本中检测和研究NP和小微塑料的改变性质带来了挑战.
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