Solvent and Solventless Hydrogels

Conventional organic solvents have been widely employed in hydrogel fabrication, but their environmental and health concerns have motivated the search for alternative solvent systems. Ionic liquids have emerged as promising substitutes, offering low volatility, high thermal stability, and improved biocompatibility. Deep eutectic solvents, formed by combining components with unique solvent properties, exhibit low toxicity, biodegradability, and potential for sustainable manufacturing. Surfactants play crucial role in emulsion-based methods, influencing hydrogel structure and properties. Solventless hydrogels, eliminating the need for solvents, provide simplified fabrication processes, reduced environmental impact, and improved biocompatibility. This chapter provides an overview of these solvent systems, discussing their advantages, limitations, and applications in hydrogel synthesis. Understanding the diverse solvent options enables the development of advanced hydrogel materials tailored for various fields, including biomedicine, tissue engineering, and other industrial applications.