1,2-Butadiene
Chemical compound
From Wikipedia, the free encyclopedia
1,2-Butadiene is the organic compound with the formula CH2=C=CHCH3. It is an isomer of 1,3-butadiene, which is a common monomer used to make synthetic rubber, and is often co-produced with it.[1] It is a colorless flammable gas, one of the simplest substituted allenes.[1]
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| Names | |
|---|---|
| Preferred IUPAC name
Buta-1,2-diene | |
| Other names
Methyl allene | |
| Identifiers | |
3D model (JSmol) |
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| 1730808 | |
| ChEBI | |
| ChemSpider | |
| ECHA InfoCard | 100.008.796 |
| EC Number |
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| 1144 | |
PubChem CID |
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| UNII | |
CompTox Dashboard (EPA) |
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| Properties | |
| C4H6 | |
| Molar mass | 54.092 g·molâ1 |
| Density | 0.676 at 4 °C |
| Melting point | â136.2 °C (â213.2 °F; 137.0 K) |
| Boiling point | 10.9 °C (51.6 °F; 284.0 K) |
Refractive index (nD) |
1.4205 at 1 °C |
| Thermochemistry | |
Enthalpy of vaporization (ÎfHvap) |
23.426 kJ/mol |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards |
Frostbite, flammable |
| GHS labelling: | |
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| Danger | |
| H220, H224, H411 | |
| P210, P233, P240, P241, P242, P243, P273, P280, P303+P361+P353, P370+P378, P377, P381, P391, P403, P403+P235, P410+P403, P501 | |
| Flash point | â75 °C (â103 °F; 198 K) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Production
The C4-fraction of petroleum obtained by cracking and separated by distillation consists of many compounds, predominantly (75%) 1,3-butadiene, isobutene, and 1-butene. 1,2âButadiene comprises less than 1% of this mixture.[2] It is partially purified by extraction with N-methylpyrrolidone. US production was 4,500â23,000 tons in 2005.[1]