- Ethylene-vinyl acetate
Ethylene vinyl acetate (CAS# 24937-78-8, also known as EVA) is the copolymer of
ethyleneand vinyl acetate. The weight percent vinyl acetate usually varies from 10 to 40% with the remainder being ethylene.
It is a
polymerthat approaches elastomeric materials in softness and flexibility, yet can be processed like other thermoplastics. The material has good clarity and gloss, barrier properties, low-temperature toughness, stress-crack resistance, hot-melt adhesivewater proof properties and resistance to UV radiation. EVA has little or no odor and is competitive with rubberand vinylproducts in many electrical applications.
foamis used as padding in equipment for various sports such as ski boots, hockey, boxing, mixed martial arts, wakeboardboots, and waterskiboots.
EVA is also used in
biomedical engineeringapplications as a drug deliverydevice. The polymer is dissolved in an organic solvent (e.g., methylene chloride). Powdered drug and filler (typically an inert sugar) are added to the liquid solution and rapidly mixed to obtain a homogeneous mixture. The drug-filler-polymer mixture is then cast into a mold at -80 degrees and freeze dried until solid. These devices are used in drug delivery research to slowly release a compound over time. While the polymer is not biodegradablewithin the body, it is quite inert and causes little or no reaction following implantation. Hot gluesticks are usually made from EVA, usually with additives like waxand resin. EVA is also used as a clinginess-enhancing additive in plastic wraps.
EVA is typically used as a shock absorber in
sports shoes, for example. EVA can be recognized in many Crocsbrand shoes and accessories, in the form of a foam called croslite.
It is also used in the
photovoltaics industry as an encapsulation material for silicon cells in the manufacture of photovoltaic modules.
EVA is one of the materials popularly known as 'expanded rubber' or 'foam rubber'.
EVA is used in Orthotics
EVA is used in Fire Safe Cigarettes.
EVA is used in the manufacture of some artificial flowers as it is easily cut from sheets of the material and molded to shape.
EVA slippers and sandals are nowadays very popular because of its properties like light weight, easy to mould, odourless, glossy finish, and cheaper compared to natural Rubber.
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