溶剂特性对热敏聚合物的临界溶液温度的影响
Konstantin Nikolaus Beitl1, Erik Reimhult1
1Institute of Colloid and Biointerface Science, Department of Bionanosciences, BOKU University, Muthgasse 11, A-1190 Vienna, Austria.
International journal of molecular sciences
|July 27, 2024
概括
热敏聚合物 (如聚N-异烯酸胺和聚2-异烯-2-氧沙) 在重水 (D2O) 和普通水 (H2O) 中显示出改变的临界溶液温度. 这些差异,受盐的影响,平均D2O测量值与H2O条件无法直接比较.
科学领域:
- 聚合物科学 聚合物科学
- 物理化学 物理化学
- 生物材料科学 生物材料科学
背景情况:
- 热敏聚合物表现出可逆的形状变化与温度,使它们有价值的医疗和生物技术应用.
- 聚N-异烯酸胺 (PNiPAm) 和聚2-异二氧化 (PiPOx) 是具有热敏性质的结构异构体.
- 将D2O和H2O中的聚合物行为进行比较至关重要,因为D2O具有不同的物理性质 (例如,较高的二极矩),可能会影响过渡.
研究的目的:
- 为了研究和比较PNiPAm和PiPOx在D2O和H2O中的临界溶液温度 (CST).
- 为了评估霍夫迈斯特系列盐对两种水同位素学者的CST的影响.
- 为了确定聚合物对溶剂同位素效应和离子强度的反应的定量差异.
主要方法:
- 动态光散射 (DLS) 用于测量聚合物过渡温度.
- 差分扫描热量计 (DSC) 用于确定过渡度并确认CST.
- 研究对D2O和H2O进行了研究,涉及多种盐度,包括宇宙和混沌.
主要成果:
- 与H2O相比,PNiPAm和PiPOx的CST在D2O中明显较低.
- 在这两种溶剂中,宇宙物降低了CST,在生理离子强度下,离子效应更为明显.
- 霍夫迈斯特离子效应在H2O和D2O之间有量差异,特别是对于化物离子 (Cl-).
- 与PNiPAm.com相比,PiPOx表现出更强的对杂态物敏感性,并表现出更高的过渡和多步过渡.
结论:
- 在D2O和H2O中测量的热敏聚合物性质的直接定量比较是不可行的,因为CST和盐效应的显著差异.
- 水同位素效应是影响聚合物行为的一个关键因素,与离子强度和特定离子效应一起.
- 了解这些溶剂特异性行为对于准确的材料设计和生物医学领域的应用至关重要.
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