Vinyl acetate

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Vinyl acetate
Skeletal formula
Ball-and-stick model
Identifiers
CAS number 108-05-4 YesY
PubChem 7904
KEGG C19309 YesY
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
Flammability code 3: Liquids and solids that can be ignited under almost all ambient temperature conditions. Flash point between 23 and 38 °C (73 and 100 °F). E.g., gasoline) Health code 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g., chloroform Reactivity code 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g., phosphorus Special hazards (white): no codeNFPA 704 four-colored diamond
Flash point −8 °C (18 °F; 265 K)
Explosive limits 2.6–13.40%
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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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[edit]

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[edit]

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[edit]

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[edit]

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[edit]

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[edit]

References[edit]

  1. ^ a b H. Chinn (September 2008). "CEH Marketing Research Report: Vinyl Acetate". Chemical Economics Handbook. SRI consulting. Retrieved July 2011. 
  2. ^ 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" 
  3. ^ 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. 
  4. ^ G. Roscher "Vinyl Esters" in Ullmann's Encyclopedia of Chemical Technology, 2007 John Wiley & Sons: New York. doi:10.1002/14356007.a27_419
  5. ^ "VP/VA Copolymer". Personal Care Products Council. Retrieved 13 December 2012. 
  6. ^ D. Swern and E. F. Jordan, Jr. (1963). "Vinyl Laurate and Other Vinyl Esters". Organic Syntheses, Collected Volume 4: 977. 
  7. ^ http://www.ec.gc.ca/ese-ees/59EC93F6-2C5D-42B4-BB09-EB198C44788D/batch2_108-05-4_pc_en.pdf

External links[edit]