Ethylene Vinyl Acetate Polymerization

245079a us 24507951 a us24507951 a us 24507951a us 2703794 a us2703794 a us 2703794a authority us united states prior art keywords ethylene vinyl acetate weight copolymer water prior art date 1951 09 04 legal status the legal status is an assumption and is not a legal.

Ethylene vinyl acetate polymerization. Vae polymerization utilizes high pressure reactions ranging between 200 and 2000. There are three different types of eva copolymer which differ in the vinyl acetate va content and the way the materials are used. A case study of adsorption and polymerization. Therefore vinyl acetate runaway polymerization incidents are very serious and they occur with a high frequency.

Vinyl acetate c4h6o2 cid 7904 structure chemical names physical and chemical properties classification patents literature biological activities safety. Vinyl acetate increases gas permeability impact strength crystallinity coefficient of. The polymerizations of vinyl acetate and ethylene caused many thermal runway accidents because of the high exothermicity. Ethylene vinyl acetate eva also known as poly ethylene vinyl acetate peva is the copolymer of ethylene and vinyl acetate the weight percent of vinyl acetate usually varies from 10 to 40 with the remainder being ethylene.

With other monomers it can be used to prepare various copolymers such as ethylene vinyl acetate eva vinyl acetate acrylic acid va aa polyvinyl chloride acetate pvca and polyvinylpyrrolidone vp va copolymer used in hair gels. As the va content increases crystallinity decreases until at 50 the eva is. 1 price 2 plastics polymers ethylene vinyl acetate 1 2 341 ethylene vinyl acetate a k a. It can be polymerized to give polyvinyl acetate pva.

The polymerization of vinyl acetate is probably the second most frequent cause of runaway reaction accidents in the chemical industry after the phenol formaldehyde runaway reaction. Eva is the copolymer of ethylene and vinyl acetate. Ethylene vinyl acetate polymerization process download pdf info. The polymerization process is hazardous because of its high thermal runaway risks 5 6 and the bulk polymerization is most harzardous among which due to the lack of solvent to dilute the heat released in polymerization.

Emblem in packaging technology 2012. Ethylene vinyl acetate eva is a random copolymer of ethylene and varying amounts of vinyl acetate va. Highly effective organometallic mediated radical polymerization of vinyl acetate using alumina supported co acac 2 catalyst. Vinyl acetate ethylene vae emulsions are based on the copolymerization of vinyl acetate and ethylene in which the vinyl acetate content can range between 60 and 95 percent and the ethylene content ranges between 5 and 40 percent of the total formulation.

The va comonomer interferes with chain packing reducing crystallinity and thus lowering t m and improving transparency when compared with ldpe.