水体积分数对阳离子交换膜中水吸附的作用
Gervasio Zaldivar1,2,3,4, Ruilin Dong4, Joan M Montes de Oca5
1Department of Chemical and Biomolecular Engineering, Tandon School of Engineering, New York University, New York, Brooklyn 11201, United States.
Macromolecules
|March 2, 2026
概括
一个新的热力学模型预测了聚合物膜中的水吸收,这对于燃料电池性能至关重要. 该模型将聚合物设计与含水量联系起来,有助于开发先进的离子交换膜.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 水的吸收显著影响了聚合物离子交换膜 (PAEM) 的特性,如离子导电性和机械强度.
- 作为电化学装置中的固体电解质,PAEMs对于能量转换至关重要.
- 将聚合物结构与吸水行为联系起来的计算模型是有限的.
研究的目的:
- 开发一种简单的热力学模型,用于预测聚电解质膜中的水吸收等温体.
- 将特定的聚合物化学设计纳入模型,以准确预测吸水率.
- 了解分子层面的相互作用,控制膜中的水吸收.
主要方法:
- 介绍一个简单的热力学模型来预测水吸收等热量.
- 将特定的聚合物化学设计纳入热力学框架.
- 通过在不同水活动中使用聚甲基膜验证模型.
主要成果:
- 该模型准确地预测了聚甲膜的水含量和宏观结构性质.
- 它成功地捕捉了各种聚合物设计参数对水吸收的影响.
- 该模型提供了对对有吸引力的相互作用及其在吸收过程中的作用的见解.
- 确定免费能源贡献的余额由水体积分数控制,独立于聚合物设计.
结论:
- 开发的热力学模型为预测PAEM中的水吸收提供了有价值的工具.
- 了解自由能量平衡的普遍行为对于设计改进的离子交换膜具有重大意义.
- 这项工作弥合了聚合物-膜水相互作用的计算方法的差距.
相关概念视频
01:17Ion Exchange
1.4K
Ion exchange chromatography separates charged molecules from a solution by reversibly exchanging them with mobile, or 'active', ions associated with the oppositely charged stationary phase. This method can be used to separate ions, soften and deionize water, and purify solutions. The polymers comprising the ion-exchange column are high-molecular-weight and chemically stable polymers, crosslinked to be porous and essentially insoluble. They are also functionalized with either acidic or...
1.4K
01:25Aquaporins
6.7K
Aquaporins or AQPs are a family of integral membrane proteins whose primary function is to transport water, while some called aquaglyceroporins also transport glycerol. In addition, aquaporins have also been suspected to be involved in transporting volatile substances, such as carbon dioxide and ammonia, across membranes. Such AQPs that act as gas channels are often highly expressed in cells involved in the gaseous exchange, such as red blood cells, epithelial cells, and pulmonary capillaries.
6.7K
01:16Solubility Equilibria: Ionic Product of Water
2.0K
Pure water is a weak electrolyte; only a small amount ionizes into hydrogen and hydroxide ions. At any given temperature, the concentration of undissociated water is almost constant, so the ionic product of water is the product of the hydrogen and hydroxide ion concentrations, denoted as Kw. The square root of Kw gives the individual ion concentrations.
The ionic product of water varies with temperature, and its value is 1.0 x 10−14 at standard experimental conditions. Per Le...
The ionic product of water varies with temperature, and its value is 1.0 x 10−14 at standard experimental conditions. Per Le...
2.0K
01:09Analyte Adsorption and Distribution
2.9K
In certain chromatographic separations, solutes transfer between the mobile phase and the stationary phase via sorption, which typically refers to the process of adsorption. For many chromatographic systems, the sorption process often depends on the polarity of the compounds—an expression of the overall dipole moment within the molecule. During the separation process, there is competition between the solute and solvent for adsorption to the stationary phase. Highly polar compounds and...
2.9K
03:13Intermolecular Forces
74.3K
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen...
74.3K
01:09Ion-Exchange Chromatography
2.5K
Ion-exchange chromatography, or IEC, is a technique for separating ions based on their affinity for the stationary phase. The stationary phase is a cross-linked polymer resin with covalently attached ionic functional groups. The functional groups can be either positively charged (cation exchangers) or negatively charged (anion exchangers). A cation exchanger consists of a polymeric anion and active cations, while an anion exchanger is a polymeric cation with active anions. The choice of...
2.5K