Vinyl acetate
| Vinyl acetate | ||
|---|---|---|
 | ||
 | ||
| IUPAC name Ethenyl acetate | ||
| 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 | 108-05-4  | |
| PubChem | 7904 | |
| KEGG | C19309 | |
| Jmol-3D images | Image 1 | |
| ||
| Properties | ||
| Molecular formula | C4H6O2 | |
| Molar mass | 86.09 g/mol | |
| Appearance | Colorless liquid | |
| Density | 0.934 g/cm3 | |
| Melting point | −93 °C; −135 °F; 180 K | |
| Boiling point | 72.7 °C; 162.9 °F; 345.8 K | |
| Hazards | ||
| MSDS | ICSC 0347 | |
| R-phrases | R11 | |
| S-phrases | S16, S23, S29, S33 | |
| NFPA 704 |
 3
2
2
| |
| Flash point | −8 °C; 18 °F; 265 K | |
| Autoignition temperature | 427 °C; 801 °F; 700 K | |
| Explosive limits | 2.6–13.40% | |
(verify) (what is: / ?)Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa) | ||
| Infobox references | ||
Vinyl acetate is an organic compound with the formula CH3CO2CHCH2. A colorless liquid with a pungent odor, it is the precursor to polyvinyl acetate, an important polymer in industry.
Production
The worldwide production capacity of vinyl acetate monomer (VAM) was estimated at 6,154,000 tonnes/annum in 2007, with most capacity concentrated in the United States (1,585,000 all in Texas), China (1,261,000), Japan (725,000) and Taiwan (650,000).[1] The average list price for 2008 was $1600/tonne. Celanese is the largest producer (ca 25% of the worldwide capacity), while other significant producers include China Petrochemical Corporation (7%), Chang Chun Group (6%) and LyondellBasell (5%).[1]
It is a key ingredient in furniture-glue.[2]
Preparation
The major industrial route involves the reaction of ethylene and acetic acid with oxygen in the presence of a palladium catalyst.[3]
- C2H4 + CH3CO2H + 1/2 O2 → CH3CO2CHCH2 + H2O
The main side reaction is the combustion of organic precursors. Vinyl acetate was once prepared by hydroesterification. This method involves the gas-phase addition of acetic acid to acetylene in the presence of metal catalysts. By this route, using mercury(II) catalysts, vinyl acetate was first prepared by Klatte in 1912.[4] Another route to vinyl acetate involves thermal decomposition of ethylidene diacetate:
- (CH3CO2)2CHCH2 → CH3CO2CHCH2 + CH3CO2H
Polymerization
It can be polymerized to give polyvinyl acetate. With other monomers is can be used to prepare copolymers such as ethylene-vinyl acetate (EVA), vinyl acetate-acrylic acid (VA/AA), polyvinyl chloride acetate (PVCA), and polyvinylpyrrolidone (Vp/Va Copolymer, used in hair gels).[5] 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 or a dithiocarbamate chain transfer agent.
Other reactions
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 generated 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.[6] The alkene also undergoes Diels-Alder and 2+2 cycloadditions.
Toxicity evaluation
On January 31, 2009, the Government of Canada's final assessment concluded that exposure to vinyl acetate is not considered to be harmful to human health.[7] This decision under the Canadian Environmental Protection Act (CEPA) was based on new information received during the public comment period, as well as more recent information from the risk assessment conducted by the European Union.
See also
References
- ↑ 1.0 1.1 H. Chinn (September 2008). "CEH Marketing Research Report: Vinyl Acetate". Chemical Economics Handbook. SRI consulting. Retrieved July 2011.
- ↑ Karl Shmavonian (2012-10-24). "Madhukar Parekh's Pidilite Industries Earns His Family $1.36 Billion". Forbes.com. Retrieved 27 January 2013. "though Pidilite has had to contend with the rising price of vinyl acetate monomer, its key raw material"
- ↑ 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:10.1016/j.jcat.2004.02.028.
- ↑ G. Roscher "Vinyl Esters" in Ullmann's Encyclopedia of Chemical Technology, 2007 John Wiley & Sons: New York. doi:10.1002/14356007.a27_419
- ↑ "VP/VA Copolymer". Personal Care Products Council. Retrieved 13 December 2012.
- ↑ D. Swern and E. F. Jordan, Jr. (1963). "Vinyl Laurate and Other Vinyl Esters". Organic Syntheses, Collected Volume 4: 977.
- ↑ http://www.ec.gc.ca/ese-ees/59EC93F6-2C5D-42B4-BB09-EB198C44788D/batch2_108-05-4_pc_en.pdf
External links
- EPA health assessment information on vinyl acetate
- CDC - NIOSH Pocket Guide to Chemical Hazards
- Summary of risk assessment by the Government of Canada