由于潮湿的蒸气而导致多电解质和多晶刷的胀
Casey J Galvin1, Michael D Dimitriou, Sushil K Satija
1Department of Chemical and Biomolecular Engineering, North Carolina State University , Raleigh, North Carolina 27695-7905, United States.
Journal of the American Chemical Society
|August 19, 2014
概括
多电解质和多晶电刷在水蒸气中表现出明显的胀行为. 波利兹维特里昂最初会膨胀,但随后由于复杂的形成而减少水的吸收.
科学领域:
- 聚合物科学 聚合物科学
- 表面化学 表面化学
- 材料科学 材料科学 材料科学
背景情况:
- 了解聚合物刷子膨胀对于涂料,传感器和生物医学设备的应用至关重要.
- 聚二甲基酸 (PDMAEMA) 和其衍生品提供基于侧链化学的调节性质.
研究的目的:
- 为了研究多电解质和多晶粉刷在各种相对湿度 (RH) 水平的水蒸气中的膨胀行为.
- 阐明侧链化学和接种密度对聚合物刷水分和结构的影响.
主要方法:
- 结合使用中子和X射线反射技术来探测刷子结构和胀.
- 用于测量光学特性和水含量的光谱圆测量仪.
- 在广泛的相对湿度 (RH) 水平范围内进行调查.
主要成果:
- 胀程度高度依赖于聚合物刷的特定侧链化学物质.
- 在聚合物/空气界面上,PDMAEMA 刷子表现出水蒸气的丰富.
- 聚聚菌刷比四分化刷有更大的胀,但由于复杂的形成,降低了70%以上的RH吸水率.
结论:
- 在聚电解质刷中没有观察到电荷排斥效应,尽管有显著的胀.
- 在高RH下,聚乙烯刷的吸水率下降归因于分子间和分子内乙烯复合体的形成.
- 接种密度梯度提供了证据,证明了在多晶体中观察到的胀行为背后的机制.
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