在poly ((diallyldimethylammonium) -poly ((styrene sulfonate) 聚电解质复合物的玻璃过渡过程中产生二元阴离子效应
Tamunoemi Braide1, Suvesh Manoj Lalwani1, Chikaodinaka I Eneh1
1Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77840, USA. jodie.lutkenhaus@tamu.edu.
Soft matter
|November 26, 2024
概括
二元盐显著影响多电解质复合物 (PEC) 特性,如玻璃过渡温度和离子相互作用. 化 (CaCl2) 由于离子特异性作用,比化 (MgCl2) 更多地增加了玻璃过渡温度.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 物理化学 物理化学
背景情况:
- 多电解质复合物 (PEC) 和多层 (PEM) 在各种应用中至关重要.
- 众所周知,它们的特性会受到水,pH值和盐度的影响.
- 双价盐对PEC组合和性质的特定影响仍然不太了解.
研究的目的:
- 调查双价化物盐 (MgCl2和CaCl2) 对聚二甲基) - - 聚硫酸 (PDADMA-PSS) PECs的物理化学性质的影响.
- 阐明离子对离子配对和PEC内部热过渡的离子特异效应.
- 建立离子相互作用,水分子和PEC的玻璃过渡温度之间的关系.
主要方法:
- 在含有不同度的MgCl2和CaCl2的溶液中组装PDADMA-PSS PEC.
- 调制差分扫描热量计 (MDSC) 用于确定玻璃过渡温度.
- 中子激活分析 (NAA) 和核磁共振 (NMR) 光谱分析聚合物组成和离子配对.
主要成果:
- 与CaCl2组装的PEC相比,与MgCl2组装的PEC表现出更高的玻璃化过渡温度.
- 确定了离子特异效应,影响了内在和外在离子配对的比率.
- 在内在离子对周围的热过渡和水分子之间发现了普遍的线性相关性,即使在双价离子中也适用.
- 双价盐在不改变结构松的情况下将桥梁引入PEC.
结论:
- 按照霍夫迈斯特序列的二元,显著影响PEC特性,特别是玻璃过渡温度和离子-离子相互作用.
- 离子特异效应决定了离子配对和水合的平衡,影响了热性质.
- 研究结果提供了关于聚合物组装中的双价离子行为的见解,与药物输送,传感器和水净化应用相关.
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