Isobutyric acid

  • 2-Methylpropanoic acid
  • Isopropylformic acid
Formula
(CH3)2CHCOOH
Structure
Description
Clear, colorless liquid with an unpleasant, pungent, butter-fat odor.
Uses
Manufacture of esters for solvents, flavors & perfume bases, disinfecting agent, varnish, deliming hides, tanning agent.

Registry Numbers and Inventories.
CAS
79-31-2
EC (EINECS/ELINCS)
201-195-7
EC Index Number
607-063-00-9
EC Class
Harmful
R 21/22
RTECS
NQ4375000
RTECS class
Primary Irritant
UN (DOT)
2529
Merck
13,5172
Beilstein/Gmelin
635770
Beilstein Reference
4-02-00-00843
EPA OPP
101502
Swiss Giftliste 1
G-8159
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C4H8O2
Formula mass
88.11
Melting point, °C
-45
Boiling point, °C
155
Vapor pressure, mmHg
1.6 (25 C)
Vapor density (air=1)
3.0
Saturation Concentration
1316 ppm (0.13%) at 14.7 C (calculated)
Odor Threshold Odor threshold 8.1 ppm in water
Critical temperature
332
Critical pressure
36.52
Density
0.949 g/cm3 (20 C)
Solubility in water
Insoluble
Viscosity
1.44 cp @ 2 15C
Surface tension
24.7 g/s2 (16 C)
Refractive index
1.3937 (20 C)
pKa/pKb
4.86 (pKa)
Partition coefficient, pKow
1.13
Heat of fusion
5.0 kJ/mol
Heat of vaporization
43.2 kJ/mol
Heat of combustion
-2185 kJ/mol

Hazards and Protection.
Storage
Keep away from heat, sparks, and flame. Keep away from sources of ignition. Keep container closed when not in use. Store in a tightly closed container. Flammables-area. Store protected from moisture.
B3 D1B E
Handling
Wash thoroughly after handling. Wash hands before eating. Remove contaminated clothing and wash before reuse. Use only in a well ventilated area. Ground and bond containers when transferring material. Use spark-proof tools and explosion proof equipment. Do not get in eyes, on skin, or on clothing. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Avoid contact with heat, sparks and flame. Do not ingest or inhale. Do not allow contact with water. Discard contaminated shoes. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames. Keep from contact with moist air and steam.
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 minimize contact with skin.
Respirators
A respiratory protection program that meets OSHA's 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator's use.
Small spills/leaks
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Clean up spills immediately, using the appropriate protective equipment. Scoop up with a nonsparking tool, then place into a suitable container for disposal. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation. Do not get water inside containers. A vapor suppressing foam may be used to reduce vapors.
Disposal code
4
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Strong oxidizing agents.
Decomposition
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide.

Fire.
Flash Point,°C
55
Autoignition, °C
500
Upper exp. limit, %
12
Lower exp. limit, %
2
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Will burn if involved in a fire. Use water spray to keep fire-exposed containers cool. Containers may explode in the heat of a fire. 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. Do NOT use water directly on fire. Use water spray to cool fire-exposed containers. Water may be ineffective. Do NOT get water inside containers. Do NOT use straight streams of water.
Fire potential
Flammable/combustible material.
Hazards
May be ignited by heat, sparks or flames. 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
When heated to decompose it emits acrid smoke and irritating fumes.
Health
3
 
Flammability
2
 
 
Reactivity
0
 

Health.
Poison_Class
3
Exposure effects
   Ingestion
Harmful if swallowed. May cause severe and permanent damage to the digestive tract. Causes gastrointestinal tract burns.
   Inhalation
Causes chemical burns to the respiratory tract. Inhalation may be fatal as a result of spasm, inflammation, edema of the larynx and bronchi, chemical pneumonitis and pulmonary edema. Vapors may cause dizziness or suffocation.
   Skin
Harmful if absorbed through the skin. Causes skin burns.
   Eyes
Causes eye burns.

First aid
 
   Ingestion
Do NOT induce vomiting. 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
Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. DO NOT use mouth-to-mouth respiration.
   Skin
Get medical aid immediately. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse. Destroy contaminated shoes.
   Eyes
Get medical aid immediately. Do NOT allow victim to rub or keep eyes closed. Extensive irrigation is required (at least 30 minutes).

Transport.
UN number
2529
Response guide
Hazard class
3
Packing Group
III
 
USCG CHRIS Code
IBR
 
HS Code
2915 60 19
 
Std. Transport #
4909366
 
IMO Chemical Code
17
IMO Pollution Category
D
IMO Hazard code
S