Monday, March 18, 2013

Hydrogel Life Cycle


Life Cycle Analysis of Hydrogel for PureVision Soft contacts (Contact Lens Material)
            Soft contact lenses are made from hydrogels, which is a material that allows for more oxygen transmission which results in better overall eye health.  The advantages of Hydrogel in contacts are more resistance to protein deposits, less drying of the lenses, lower risk of eye infection, easier handling due to increased rigidity of material, and much lower incidence of complications with extended wear use. 
           
Poly (hydroxyethyl methacrylate) or PHEMA is what hydrogel is mostly comprised of.  This is made by polymerizing 2-hydroxyethyl methacrylate monomer with a cross-linker such as ethylene glycol dimethacrylate.  The rest of the Hydrogel is comprised of water, which is about 38 to 40% of the material.  
           
Hydrogels help reduce water runoff and soil erosion, thus improving the quality of lakes, streams, and rivers. Hydrogels also help with moisture retention and water conservation by helping soil increase water holding capacity, allowing plants to survive during droughts. Erosion control, soil management, and environmental clean-ups are also ways hydrogels can help the environment

            Hydrogels are not materials found in the environment, rather a synthesized material which is made from cross linkage and therefore is not needed to have a material harvested to create.  Rather, Hydrogels easily dehydrate and are easily disposed of or recycled, since it is a permeable plastic, so as not to be damaging to the ecosystem.