Effect of Cation/Anion Structure on Phase Transition Behavior of Thermoresponsive Poly(IL) Gels for Solar Driven Water Purification

DOI

10.2991/978-94-6239-717-0_13How to use a DOI?

Keywords

Ionic liquid; hydrogel; LCST; purification

Abstract

The increasing global population has led to a growing demand for clean water, accelerating the development of innovative, electricity-free purification systems for remote areas. A promising solution is a solar-driven water purification system that utilizes thermoresponsive hydrogels to adsorb and desorb water in response to temperature changes. This study investigates the influence of the molecular structures of both anions and cations in poly(IL) gels on their water adsorption/desorption behavior and phase transition temperature control. While previous research has focused on the properties of homopolymer gels, this study systematically investigated the distinct roles of the anionic and cationic structures by synthesizing and evaluating copolymer hydrogels with a unified anionic or cationic structure, respectively. We synthesized copolymer hydrogels with unified anionic and cationic structures, respectively, and evaluated their water adsorption/desorption capabilities. The results demonstrated that the hydrophilic/hydrophobic balance provided by the cationic structure is crucial for controlling the phase transition temperature while maintaining a dramatic water adsorption/desorption response to temperature changes. Specifically, in the system with varying anionic alkyl chain lengths, the LCST was shown to shift to lower temperatures as the chain length increased. Conversely, the system with varying cationic alkyl chain lengths exhibited linear dehydration behavior, suggesting that the [N4] cation structure plays a critical role as a scaffold enabling a cooperative phase transition. These findings contribute to the control of the phase transition behavior and the improvement of functions such as water adsorption/desorption capability in poly(IL) gels.

Copyright

© 2026 The Author(s)

Open Access

Open Access This chapter is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/), which permits any noncommercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

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TY  - CONF
AU  - Takumi Takahashi
AU  - Masaki Tanaka
AU  - Takahiro Ichikawa
AU  - Nobuhumi Nakamura
PY  - 2026
DA  - 2026/06/25
TI  - Effect of Cation/Anion Structure on Phase Transition Behavior of Thermoresponsive Poly(IL) Gels for Solar Driven Water Purification
BT  - Proceedings of the 19th International Conference on Quality in Research (QiR 2025)
PB  - Atlantis Press
SP  - 173
EP  - 189
SN  - 2352-5401
UR  - https://doi.org/10.2991/978-94-6239-717-0_13
DO  - 10.2991/978-94-6239-717-0_13
ID  - Takahashi2026
ER  -