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Polymer applications. isomers. Heart Valves. . Allows flow of blood in one direction • Significant cause of mortality worldwide • Two Types: – Biological: Animal valvea (ex. Pigs) – Mechanical: Carbon, metallic and polymeric • Issues with current valves:
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Polymer applications isomers
Heart Valves. Allows flow of blood in one direction • Significant cause of mortality worldwide • Two Types: – Biological: Animal valvea (ex. Pigs) – Mechanical: Carbon, metallic and polymeric • Issues with current valves: – Mechanical: susceptible to clotting (warfarin regimen) – Biological: lack of durability
Heart Valves • Polymeric Heart Valves • – Current types: Polyurethane, Silicone • – POSS PCU • Resistance to oxidation, hydrolysis, and calcification • Biocompatibility • Anti-thrombogenicity (no warfarin regimen required) • No negative feedback • Development currently under investigation
Oil Lubricants Needs to be able to resist mechanical and thermal stress Improve the viscosity of the oil Resist free radical reactions methyl methacrylate polymer Self Healing polymer Starfish shaped Diels Alder adducts into the polymer backbone which allow them to reform via a Diels Alder cycloaddition reaction
Silicone Hydrogel Contact Lenses Among Americans who need vision correction, about 20% wear contact lenses. •Traditional soft contact lenses are made from hydrogel polymers (soft, water-containing plastics). The plastic itself is not oxygen permeable, so the water content performs the job of carrying oxygen through the lens to the eye. But water can carry only so much oxygen — and the more water a lens contains, the greater its tendency to dehydrate after long periods of wear. •Silicone is oxygen permeable. So silicone hydrogel lenses use both their water and polymer content to transmit oxygen to the eye. •Ideal for users who tend to sleep in their lenses.
Advantages • The overall benefit is one of comfort and convenience to the user. • – Silicone hydrogel contact lenses contain less water than traditional hydrogel lenses. As a result, they aren't as prone to dehydration while you're wearing them. For some people who wear their lenses for long days, this can mean better end- of-day comfort. • – Silicone hydrogels also have made 30-day contact lens wear — sometimes called "continuous wear" — available once again.
Rankings The Rankings were Based on their application and helpfulness to society The Heart Valve was chosen as number 1 because it can potentially save lives The oil lubrication was chosen as number 2 because it can greatly extend the life of oils saving money The eye contacts were chosen last because the customer could take the contacts out before they go to bed. It just is more convenient