Hydrogels are a network of cross-linked polymers with the ability to retain a large amount of water. This trait could be leveraged in many different areas of human spaceflight, a sector that is characterized by strict mass, volume, and manufacturability requirements. However, the potential applications for hydrogels have been largely unexplored for space exploration with minimal testing in microgravity. Through adjusting polymer concentration, infusing different additives, or other methods of varying synthesis, hydrogels can take on a wide range of characteristics, making them highly versatile. Infusing hydrogels with these additives has demonstrated superior performance in comparison to utilizing the pure additive independently, particularly notable in the context of carbon dioxide removal, where solid amine infused hydrogels outperform bulk amine solutions. In addition, hydrogels can be 3D printed into any form they need to take on and, through 3D printing, can have microelectronics embedded within them for effective control. Recently hydrogels have been developed that are recyclable and reformable, allowing for the same material to be reused for different purposes over time. Specific examples of hydrogel use in human spaceflight such as atmospheric water control and wound dressing will be proposed in length. Hydrogels' effectiveness in many different applications has led to exponential growth in attention over time and studying these applications for human spaceflight is critical for leveraging this novel material.
Greaves et al. (Sun,) studied this question.