🔆What are Hydrogels? ✅Hydrogels are three-dimensional networks of water-soluble polymers that can absorb and retain a large amount of water without losing their structural integrity. ✅They are super-soft and transparent materials that can shrink or swell when exposed to water. ✅Hydrogels are made by crosslinking polymer chains through chemical reactions. ✅Poly(2-hydroxyethyl methacrylate) (pHEMA): This was the first hydrogel material used in contact lenses, offering flexibility and comfort. ✅Silicone Hydrogel Lenses: These are a variation of hydrogel lenses that improve oxygen permeability, allowing for extended wear and increased comfort. ✅Modified Hydrogels: These are hydrogels that have been modified to enhance their properties, such as increasing water content and oxygen permeability. #gs3 #prelims #science_technology