1,2-Butadiene

  • Methylallene
  • 1-Methylallene
  • Buta-1,2-diene
Formula
C4H6
Structure
Description
Volatile, clear, colorless liquid or vapor.
Uses
Gel inhibitor in olefin polymerization.

Registry Numbers and Inventories.
CAS
590-19-2
EC (EINECS/ELINCS)
209-674-2
UN (DOT)
1012
Beilstein/Gmelin
1730808
Beilstein Reference
4-01-00-00975
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C4H6
Formula mass
54.09
Melting point, °C
-136.2
Boiling point, °C
10.9
Vapor pressure, mmHg
1260 (25 C)
Vapor density (air=1)
1.9
Density
0.676 g/cm3 (0 C)
Solubility in water
Insoluble
Refractive index
1.4205 (1 C)
Heat of fusion
9.97 kJ/mol
Heat of vaporization
23.4 kj/mol
Heat of combustion
-2599 kJ/mol

Hazards and Protection.
Storage
Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Wear appropriate protective gloves, clothing and goggles. Always wear thermal protective clothing when handling refrigerated/cryogenic liquids.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Make no contact with the spilled material. ELIMINATE all ignition sources, combustibles and ground all equipment. Take up with sand or other noncombustible absorbent material and place into containers for later disposal.
Stability
No data.
Incompatibilities
1,2-butadiene reacts rapidly with ozone under standard laboratory conditions (-78 C in methanol) to produce carbon monoxide, acetaldehyde, some peroxidic compounds, and acetic acid.

Fire.
Flash Point,°C
-76
Upper exp. limit, %
12
Lower exp. limit, %
2
Fire fighting
Extinguish fire with flooding quantities of water or use dry chemical or carbon dioxide.
Fire potential
A dangerous fire hazard.
Hazards
Vapors from liquefied gas are initially heavier than air and spread along ground. Vapors may travel to source of ignition and flash back. Containers may explode when heated.

Health.
Exposure effects
Animal studies have shown mild anesthesia at 150,000 to 200,000 ppm. 250,000 Ppm has caused death by respiratory paralysis. Drowsiness and fatigue have been reported in workers exposed to high concentrations. This agent is a CNS depressant. Malformations have been seen in rats.
   Ingestion
Respiratory paralysis resulting in death has occurred in animals. Coughing has been reported from higher but unspecified exposure concentrations in humans. Asphyxiation can occur.
   Inhalation
Respiratory paralysis resulting in death has occurred in animals. Coughing has been reported from higher but unspecified exposure concentrations in humans.
   Skin
Splash contact may cause mild to moderate skin irritation or frostbite.
   Eyes
May cause irritation.

First aid
 
   Ingestion
The possible benefit of early removal of some ingested material by cautious gastric lavage must be weighed against potential complications of bleeding or perforation. Activated charcoal activated charcoal binds most toxic agents and can decrease their systemic absorption if administered soon after ingestion. Activated charcoal: administer charcoal as a slurry (240 ml water/30 g charcoal). Usual dose: 25 to 100 g in adults/adolescents.
   Inhalation
Move patient to fresh air. Monitor for respiratory distress. If cough or difficulty breathing develops, evaluate for respiratory tract irritation, bronchitis, or pneumonitis. Administer oxygen and assist ventilation as required. Treat bronchospasm with beta2 agonist and corticosteroid aerosols.
   Skin
Remove contaminated clothing and wash exposed area thoroughly with soap and water. A physician should examine the area if irritation or pain persists.
   Eyes
Irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility.

Transport.
UN number
1012
Response guide
Hazard class
2.1