The toughness of a hydrogel refers to the ability of the hydrogel to withstand deformation or mechanical stress without fracturing or breaking apart. A hydrogel with high toughness can maintain its structural integrity and functionality under higher stress.
A hydrogel is a network of hydrophilic polymers that are crosslinked either through physical entanglement (reversible hydrogel) or covalent bonds (permanent hydrogel), whilst a gel is a semi-solid material of hydrophilic polymers consisting of large amounts of liquid and small amounts of solids.
In the present review, we focused on the fundamental concepts of hydrogels—classification, the polymers involved, synthesis methods, types of hydrogels, properties, and applications of the hydrogel.
Hydrogels are three-dimensional (3D) structured networks of crosslinked hydrophilic polymer matrices capable of holding a large amount of water (> 10%by definition) and displaying useful characteristics such as softness, toughness, biocompatibility, stretchability, and deformability.
Hydrogels are materials composed of polymer chains that form a network capable of absorbing and holding significant amounts of water. This unique structure gives them a soft, jelly-like consistency, resembling biological tissues. These versatile materials are found in many aspects of modern life, from medical treatments to everyday consumer goods.
Hydrogels are materials that can absorb and hold large amounts of water. They are made up of hydrophilic functional groups that attach to polymers and are cross-linked via hydrogen bonding and other interactions to form a three-dimensional mesh structure.
Hydrogels are three-dimensional networks of hydrophilic polymers that absorb and retain large amounts of water while maintaining their structure. Their stability comes from chemical or physical cross-linking between polymer chains, allowing them to swell without dissolving.
Liquid water trapped in tangled polymers gives this material strangely useful properties. This close-up shows colorful hydrogel toy spheres known as “orbeez" or water beads. These are pretty when all plumped up but they're not meant for eating.