Elvax® Ethylene/vinyl acetate copolymers

Elvax Ethylene-vinyl Acetate Copolymer Resins, Data Sheets and Other Technical Literature, DuPont Paekaging, E. I. DuPont de Nemours and Company. 

Elvax Ethylene-vinyl acetate copolymers, EVAc Du Pont/Safic-Alcan... 

Ref 94 covers studies involving use of Mobil-wax 2300 microcrystalline wax, paraffin wax, ethylene vinyl acetate copolymer (Elvax 40,... 

Most hot-melts are based on polyolefins. The best known hot-melt is ethylene-vinyl acetate copolymer (EVA), e.g., duPont Elvax. In 1983, duPont added a new line of resins... 

EVAc Ethylene-vinyl acetate copolymer Elvax E. I. du Pont de Nemours Co. 

Low-density polyethylene was utilized as the control (LF-0219-A Novapol). The ethylene-vinyl acetate copolymers varied in vinyl acetate content from 9.3, 18, 28, to 40% (Elvax 760Q, 460, 265, and 40L-03, respectively DuPont). The organomontmorillonites that were evaluated were Cloisite 20A, Cloisite 30B, and montmorillonite exchanged with trimethyl hydrogenated tallow quaternary ammonium ion at the exchange capacity of the montmorillonite. 

Elvax 265, 40L03 Ethylene/vinyl acetate copolymer DuPont Company... 

General Description Ethylene Vinyl Acetate (EVA) Copolymer is a copolymer resin ranging in vinyl acetate content from 7.5 wt% to 33 wt%. DuPont Elvax and Equistar Ultrathene grades vary by vinyl acetate content. Some grades are available with antiblock and slip additives. The vinyl acetate units in the copolymer modify the basic polyethylene structure and its properties. The addition of vinyl acetate to polyethylene provides lower sealing temperature, increased flexibility, improved optical properties, greater adhesion, increased impact, and puncture resistance. 

Ethylene has also been copolymerised with a number of non-olefinic monomers and of the copolymers produced those with vinyl acetate have so far proved the most significant commercially . The presence of vinyl acetate residues in the chain reduces the polymer regularity and hence by the vinyl acetate content the amount of crystallinity may be controlled. Copolymers based on 45% vinyl acetate are rubbery and may be vulcanised with peroxides. They are commercially available (Levapren). Copolymers with about 30% vinyl acetate residues (Elvax-Du Pont) are flexible resins soluble in toluene and benezene at room temperature and with a tensile strength of about lOOOlbf/in (6.9 MPa) and a density of about 0.95 g/cm. Their main uses are as wax additives and as adhesive ingredients. 

Certain copolymers of ethylene and vinyl acetate, poly[ethylene-co-(vinyl acetate)] (EVAc, ELVAX , Dupont Corp.), have exceptionally good biocompatibility and are therefore widely used in implanted and topical devices. 

The copolymer is synthesized by free-radical polymerization from ethylene and vinyl acetate. The most commonly used EVAc (ELVAX-40, DuPont) consists of 40% vinyl acetate, with a low degree of crystallinity (5-20%). EVAc is hydrophobic it swells less than 0.8% in water [28]. 

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