2-Methyl-2-butene

  • Amylene
  • b-Isoamylene
  • 2-Methylbut-2-ene
Formula
(CH3)2C=CHCH3
Structure
Description
A clear colorless volatile liquid with a petroleum-like odor.
Uses
Principally chemical intermediate for isoprene, additive in high octane fuel mfr, chemical intermediate for the pharmaceutical solvent, tertiary pentyl alcohol.

Registry Numbers and Inventories.
CAS
513-35-9
EC (EINECS/ELINCS)
208-156-3
RTECS
EM7650000
UN (DOT)
2460
Merck
12,649
Beilstein/Gmelin
1361353
Beilstein Reference
4-01-00-00820
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C5H10
Formula mass
70.13
Melting point, °C
-124
Boiling point, °C
39
Vapor pressure, mmHg
468 (25 C)
Vapor density (air=1)
2.4
Critical temperature
198
Critical pressure
33.7
Density
0.6623 g/cm3 (20 C)
Solubility in water
Insoluble
Viscosity
3.1641x10-3 pa/s @ 139.39 K
Surface tension
17.26 g/s2 (20 C)
Refractive index
1.3874 (20 C)
Partition coefficient, pKow
2.92
Heat of vaporization
34.6 kJ/mol
Heat of combustion
-1484 kJ/mol

Hazards and Protection.
Storage
Keep away from heat, sparks, and flame. Keep away from sources of ignition. Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances.
Handling
Wash thoroughly after handling. Use only in a well ventilated area. Ground and bond containers when transferring material. Avoid contact with eyes, skin, and clothing. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Keep container tightly closed. Avoid contact with heat, sparks and flame. Avoid ingestion and inhalation. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Remove all sources of ignition. A vapor suppressing foam may be used to reduce vapors. Water spray may reduce vapor but may not prevent ignition in closed spaces.
Stability
Stable under normal shipping and handling conditions.
Incompatibilities
Oxidizing agents
Decomposition
Irritating and toxic fumes and gases.

Fire.
Flash Point,°C
-7
Upper exp. limit, %
9.6
Lower exp. limit, %
1.4
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Use water spray to keep fire-exposed containers cool. Extremely flammable liquid. Containers may explode in the heat of a fire. Will be easily ignited by heat, sparks or flame. Extinguishing media: For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. For large fires, use water spray, fog, or alcohol-resistant foam. Use water spray to cool fire-exposed containers. Water may be ineffective. Do NOT use straight streams of water.
Fire potential
HIGHLY FLAMMABLE.
Hazards
Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. May polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.
Health
1
 
Flammability
3
 
 
Reactivity
0
 

Health.
Exposure effects
Mild central nervous system depression or excitation may occur after ingestion or vapor inhalation. CNS effects can occur secondary to hydrocarbon pneumonitis and hypoxia, or from additives and contaminants (aniline, heavy metals, camphor, or pesticides). Some hydrocarbons are simple asphyxiants (e.G., Methane, ethane, propane gasses) which can produce CNS effects secondary to hypoxia. In a prospective study in Toronto, major congenital malformations were noted in 13 of 125 fetuses of mothers exposed to organic solvents during pregnancy.
   Ingestion
May cause irritation of the digestive tract.
   Inhalation
Vapors may cause dizziness or suffocation.
   Skin
May cause skin irritation.
   Eyes
May cause eye irritation.

First aid
 
   Ingestion
If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
   Skin
Get medical aid. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Transport.
UN number
2460
Response guide
Hazard class
3
Packing Group
II
 
USCG CHRIS Code
PTX
 
Std. Transport #
4906018
 
IMO Chemical Code
17
IMO Pollution Category
C
IMO Hazard code
P