Vinyl acetate
From Wikipedia, the free encyclopedia
| Vinyl acetate | |
|---|---|
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| IUPAC name |
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| Systematic name | Ethenyl ethanoate |
| Other names | Acetic acid vinyl ester, acetoxyethene, VyAc, VAM, zeset T, VAM vinyl acetate monomer, acetic acid ethenyl ester, 1-acetoxyethylene |
| Identifiers | |
| CAS number | [] |
| PubChem | |
| SMILES |
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| Properties | |
| Molecular formula | C4H6O2 |
| Molar mass | 86.09 g/mol |
| Appearance | Colorless liquid |
| Density | 0.934 g/cm3 |
| Melting point |
-93 °C, 180 K, -135 °F |
| Boiling point |
72.7 °C, 346 K, 163 °F |
| Hazards | |
| R-phrases | R11 |
| S-phrases | S16, S23, S29, S33 |
| NFPA 704 |
 3
2
2
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| Flash point | -8°C |
| Autoignition temperature |
427 °C |
| Explosive limits | 2.6–13.40% |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox references |
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Vinyl acetate is an organic compound with the formula CH3COOCH=CH2. A colorless liquid with a pungent odor, it is the precursor to polyvinyl acetate, an important polymer in industry.
Like many industrially significant compounds, vinyl acetate has numerous names and acronyms. Polyvinyl acetate is frequently referred to as PVAc or PVA, vinyl acetate is also called VAM (vinyl acetate monomer).
Contents |
[edit] Preparation
The major industrial route involves the reaction of ethylene and acetic acid with oxygen in the presence of a palladium catalyst.[1]
- Ethylene + acetic acid + 1/2 O2 → Vinyl acetate + H2O
But byproducts are also generated:
- Ethylene + 3 O2 → 2 CO2 + 2 H2O
Vinyl acetate is also prepared by the gas-phase addition of acetic acid to acetylene.[2]
[edit] Polymerization
It can be polymerized, either by itself to make polyvinyl acetate or with other monomers to prepare copolymers such as ethylene-vinyl acetate. Due to the instability of the radical, attempts to control the polymerization via most 'living/controlled' radical processes have proved problematic. However, RAFT (or more specifically MADIX) polymerization offers a convenient method of controlling the synthesis of PVA by the addition of a xanthate chain transfer agent.
[edit] Other derivatives
Vinyl acetate undergoes many of the reactions anticipated for an alkene and an ester. Bromine adds to give the dibromide. Hydrogen halides add to give 1-haloethyl acetates, which cannot be generate by other methods because of the non-availability of the corresponding halo-alcohols. Acetic acid adds in the presence of palladium catalysts to give ethylidene diacetate, CH3CH(OAc)2. It undergoes transesterification with a variety of carboxylic acids.[3] The alkene also undergoes Diels-Alder and 2+2 cycloadditions.
[edit] Possible label as "toxic" in Canada
Due to research done by the International Agency for Research on Cancer that the substance could be linked to cancer in lab rats, a draft report due from the Government of Canada may label it toxic, along with as many as sixteen other substances.[4]
[edit] References
- ^ Y.-F. Han, D. Kumar, C. Sivadinarayana, and D.W. Goodman (2004). "Kinetics of ethylene combustion in the synthesis of vinyl acetate over a Pd/SiO2 catalyst". Journal of Catalysis 224: 60–68. doi:. http://www.chem.tamu.edu/rgroup/goodman/pdf%20files/442_joc-224-04-60.pdf.
- ^ G. Roscher "Vinyl Esters" in Ullmann’s Encyclopedia of Chemical Technology, 2007 John Wiley & Sons: New York.
- ^ D. Swern and E. F. Jordan, Jr (1963). "Vinyl Laurate and Other Vinyl Esters". Organic Syntheses, Collected Volume 4: 977. http://www.orgsyn.org/orgsyn/pdfs/CV4P0977.pdf.
- ^ "Chewing gum substance could be toxic". Vancouver Sun. 2008-05-13. p. A4.
