Glassy Gels Toughened by Solvent

Glassy polymers and gels are typically considered distinct classes of materials. Many plastics in our day-to-day life, such as a water bottle, are glassy polymers. They are stiff, strong, but often brittle. These mechanical properties arise due to interactions between polymer chains. They are called glassy because the polymers are “stuck“; that is, they cannot move easily. If you heat these materials, it will soften because the polymers start moving. The temperature where it softens is called a “glass transition temperature“ Another way to soften a glassy polymer is to add liquid. The resulting material is called a gel. A great example is a contact lens, which contains water. The liquid (or small molecule) goes between the polymer chains and makes it easier to move. Gels are soft, stretchable, but not very strong. What if adding liquid could make a material more stretchable, but without making it softer? We managed to do this using a liquid called “ioni