Ethylene-vinyl alcohol copolymer EVAL EVOH

Ethylene vinyl alcohol copolymer (EVAL , EVOH) Asahi Kasei Medical Co., Ltd., Tokyo, Japan KF-201-1.3C... 

Group 4, Ethylene vinyl alcohol copolymer family Manber Ethylene vinyl alcohol copolymer (EVAL, EVOH, Kawasumi/Kuraray Laboratories, Japan) with of a series of different EVAL/EVOH modifications (Table 13.6). 

The ethylene vinyl alcohol copolymer (EVAL/EVOH) is a hydrophilic and uncharged synthetic polymer blend [62]. The polymer used to fabricate EVOH membranes is a random copolymer of ethylene and vinylalcohol. Due to its original hydrophilicity, no hydrophilizing agents, such as polyvinylpyrrolidone (PVP), are needed. EVOH membranes have a smooth surface and retain stmctnral water. As a consequence, they adsorb few plasma proteins and membrane fonfing during... 

Ethylene vinyl alcohol copolymer (EVAL or EVOH)... 

There are two polymers used in a maj ority ofhigh barrier food packages copolymers containing polyvinylidene chloride (Saran ) and ethylene-vinyl alcohol copolymer (Eval, Selar-OH ). Packages in which either polyvinylidene chloride or ethylene-vinyl alcohol copolymer (EvOH) provide the barrier are invariably multilayer since neither of these materials offers the properties required to make a good monolayer structure. There are advantages and disadvantages associated with each of these materials, and the... 

EUROMAP European Committee of Machine Manufacturers for the Rubber Plastics Industries (Zurich, Swiz.) EVAL ethylene-vinyl alcohol copolymer (or EVOH)... 

Ethylene-vinyl alcohol copolymer (EVAL, E/ VAL, and EVOH) n. A family of copolymers made by hydrolyzing ethylene-vinyl acetate copolymers with high VA content. Those containing about 20-35% ethylene are useful as barriers to many vapors and gases, though not to water. Because of their water sensitivity, they are usually sandwiched between layers of other polymers. 

EvOH- 32 refers to ethylene-vinyl alcohol copolymer with 32 mol % ethylene. All subsequent references to EvOH-32 will be for Evalca Eval-F grade material. ... 

EVOH Ethylene vinyl alcohol copolymer Clarene Eval... 

Ethylene vinyl alcohol copolymer (EVOH, Eval F 171 A) was provided by Eval Con any of America. Adhesive resin (M eic anhydride modified polypropylene, PP-g-MA, Orevac 18729) was provided by Aikema Inc. 

Hydrolyzed ethylene—vinyl acetate copolymers [24937-78-8]> commonly known as ethylene—vinyl alcohol (EVOH) copolymers [25067-34-9], are usually used as extrusion resins, although some may be used in solvent-coating applications. As the ethylene fraction of these semicrystalline copolymers increases, the melting temperature decreases, the permeabilities increase, and the sensitivity to humidity decreases. The permeabilities as a function of polymer composition and humidity are shown in Figure 2. Vinyl alcohol homopolymer [9002-89-5] has a very low oxygen permeability in dry conditions however, the polymer is water-soluble. Trade names for these barrier polymers include Eval, Soamol, Selar OH, and Qarene. Table 6 lists the compositions... 

Polyethylene-co-vinyl alcohol resins are produced indirectly by the hydrolysis (saponification) of ethylene-co-vinyl acetate copolymers. The structure of the vinyl alcohol branch is shown in Figure 9. Hydrolysis can be achieved by the action of alcoholic sodium hydroxide or potassium hydroxide in an organic solvent solution at high temperature [84,86]. Ethylene-co-vinyl alcohol copolymers are often referred to as EVAL (pronounced as a single word) or by the abbreviation EVOH. Like their ethylene-co-vinyl acetate precursors, ethylene-co-vinyl alcohol copolymers also contain short- and long-chain branching. 

PVA copolymers of vinyl alcohol and ethylene, poly[(vinyl alcohol)-co-ethylene] (EVOH), is industrially produced in significant quantities as an engineering plastic known as EVAL. A thermophilic EVOH-assimilating strain. Bacillus stearothermophilus, was isolated from the soil at 60 C by Tomita et al (1997). The apparent Fmax/ m value of the PVA copolymer with 10 mol% ethylene was over 10-fold greater than that of PVA (Hatanaka et al, 1995b). 

Ethylene copolymers are produced i) with vinyl acetate (EVA, EVAC), ii) with vinyl alcohol (EVOH, EVAL), iii) as binary copolymers and terpolymers with acrylics (E/EA, E/MA, E/AA etc.), or iv) as lonomer resins. Olefinic thermoplastic elastomers (TPE) are available, usually PP based with EPM or EPDM rubber additions that may be lightly crosslinked. Polypropylenes are offered in various forms homopolymers, block copolymers, random copolymers and mixtures of types. Polybutylene (PB) and Polymethylpentene (PMP) complete the range. 

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