聚乙烯氧化物溶液表面张力的分子重量依赖性
Jianwei Zhang1, Lu Qian1, Jiajia Zhou2,3
1Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
The journal of physical chemistry. B
|July 24, 2023
概括
聚乙烯氧化物溶液的表面张力取决于分子量和表面的聚合物吸附. 较低的溶剂质量和较高的聚合物度降低了临界分子量.
科学领域:
- 物理化学 物理化学
- 聚合物科学 聚合物科学
- 表面科学是一门学科.
背景情况:
- 表面张力对于湿和粘附等现象至关重要.
- 了解聚合物溶液的行为是材料科学中的关键.
研究的目的:
- 研究聚乙烯氧化物溶液中表面张力和分子量之间的关系.
- 探索溶剂质量和聚合物度对表面张力特性的影响.
主要方法:
- 结合实验测量与分子动力学 (MD) 模拟.
- 使用粗粒聚合物溶液模型进行模拟.
主要成果:
- 表面张力 (γ) 与分子重量 (M) 的尺度是: - Mα 到一个临界分子重量 (M*).
- 缩放指数α随着溶剂质量的恶化而下降,并且受到聚合物度的影响很小.
- 随着溶剂质量的降低和聚合物度的增加,M*会降低.
结论:
- 在空气溶液接口的聚合物吸附决定了聚乙烯氧化物溶液的表面张力.
- 溶剂质量和聚合物度显著影响临界分子量和缩放行为.
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