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Polyvinyl alcohol (PVOH, PVA, or PVAl) is a water-soluble synthetic polymer. It has the idealized formula [CH 2 CH(OH)] n . It is used in papermaking , textile warp sizing , as a thickener and emulsion stabilizer in polyvinyl acetate (PVAc) adhesive formulations, in a variety of coatings, and 3D printing .
Formvar refers to any of several thermoplastic resins that are polyvinyl formals, which are polymers formed from polyvinyl alcohol and formaldehyde as copolymers with polyvinyl acetate. They are typically used as coatings, adhesives , and molding materials.
Polyethylene glycol–polyvinyl alcohol (PEG-PVA) brand name Kollicoat IR is a multifunctional excipient [1] used as a pill binder as well as a wet binder. A typical formulation is composed of 25% polyethylene glycol (PEG) and 75% polyvinyl alcohol (PVA); where the vinyl alcohol moieties are grafted on a polyethylene glycol backbone.
Vinyl polymers are subject of several structural variations, which greatly expands the range of polymers and their applications. With the exception of polyethylene, vinyl polymers can arise from head-to-tail linking of monomers, head-to-head combined with tail-to-tail, or a mixture of those two patterns. Additionally the substituted carbon center in such polymers is stereogenic (a "chiral center")
Ethylene vinyl alcohol (EVOH) is a formal copolymer of ethylene and vinyl alcohol. Because the latter monomer mainly exists as its tautomer acetaldehyde , the copolymer is prepared by polymerization of ethylene and vinyl acetate to give the ethylene vinyl acetate (EVA) copolymer followed by hydrolysis.
Vinyl acetate is the acetate ester of vinyl alcohol. Since vinyl alcohol is highly unstable (with respect to acetaldehyde), the preparation of vinyl acetate is more complex than the synthesis of other acetate esters. The major industrial route involves the reaction of ethylene and acetic acid with oxygen in the presence of a palladium catalyst. [6]
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In enzymology, a polyvinyl-alcohol oxidase (EC 1.1.3.30) is an enzyme that catalyzes the chemical reaction. polyvinyl alcohol + O 2 oxidized polyvinyl alcohol + H 2 O 2. Thus, the two substrates of this enzyme are polyvinyl alcohol and O 2, whereas its two products are oxidized polyvinyl alcohol and H 2 O 2.