Polyvinyl acetate | |
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poly (1-acetyloxiethylene) |
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Other names
PVAc, PVA |
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Identifiers | |
CAS number | 9003-20-7 |
PubChem | 7758 |
KEGG | C12282 |
Jmol-3D images | Image 1 |
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Properties | |
Molar mass | 86.09 g/mol/unit |
Hazards | |
MSDS | MSDS |
(verify) (what is: / ?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) |
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Infobox references |
Polyvinyl acetate, PVA, PVAc, poly(ethenyl ethanoate), is a rubbery synthetic polymer with the formula (C4H6O2)n. It belongs to the polyvinyl esters family with the general formula -[RCOOCHCH2]-. It is a type of thermoplastic.[1]
It should not be confused with the related polymer polyvinyl alcohol, which is called PVA also (PVAc could be considered a technically correct abbreviation for polyvinyl acetate and would aid in avoiding such confusion).
Polyvinyl acetate is a component of a widely-used type of glue, referred to variously as wood glue, white glue, carpenter's glue, school glue or PVA glue.
Contents |
PVAc is a vinyl polymer. Polyvinyl acetate is prepared by polymerization of vinyl acetate monomer ( free radical vinyl polymerization of the monomer vinyl acetate).
Polyvinyl acetate was discovered in Germany in 1912 by Dr. Fritz Klatte.[2]
The monomer, vinyl acetate, was on an industrial scale first produced by addition of acetic acid to acetylene with a mercury(I) salt[3] but it is now primarily made by palladium catalyzed oxidative addition of acetic acid to ethylene.
The degree of polymerization of polyvinyl acetate typically is 100 to 5000. The ester groups of the polyvinyl acetate are sensitive for alkali and will slowly convert PVAc into polyvinyl alcohol and acetic acid.
Under alkaline conditions, boron compounds, such as boric acid or borax causes the polymer to cross-link forming tackifying precipitates or slime.
As an emulsion in water, PVAc emulsions are used as adhesives for porous materials, particularly for wood, paper, and cloth, and as a consolidant for porous building stone, in particular sandstone.[4] Uses:
The stiff homopolymer PVAc , but mostly the more soft copolymer a combination of vinyl acetate and ethylene, vinyl acetate ethylene (VAE), is used also in paper coatings, paint and other industrial coatings, as binder in nonwovens in glass fibers. sanitary napkins, filter paper and in textile finishing
PVAc can also be used as coating to protect cheese from fungi and humidity.
Polyvinyl acetate is also the raw material to make other polymers like: