- Crotonic aldehyde
- Propylene aldehyde
Water-white liquid, suffocating, pungent odor, lachrymator.
Intermediate for 2-ethylhexyl alcohol, solvent, prepn of rubber accelerators, purification of lubricating oils, insecticides, tear gas, organic synth, leather tanning, alc denaturant.
Registry Numbers and Inventories.
EC Index Number
Highly flammable; Mutagenic Category 3; Very toxic; Toxic; Harmful; Irritant; Dangerous for the Environment
R 11 24/25 26 37/38 41 48/22 50 68
S 26 28.1 36/37/39 45 61
Japan ENCS (MITI)
Melting point, °C
Boiling point, °C
Vapor pressure, mmHg
31 (25 C)
Vapor density (air=1)
39480 ppm (3.9%) at 20 C (calculated)
Odor Threshold Odor threshold 2.10X10-2 mg/L
0.858 g/cm3 (20 C)
Solubility in water
180 g/L (20 C)
1.4384 (20 C)
Partition coefficient, pKow
Heat of vaporization
Heat of combustion
Hazards and Protection.
Keep away from heat, sparks, and flame. Keep away from sources of ignition. Store in a tightly closed container. Keep from contact with oxidizing materials. Store in a cool, dry, well-ventilated area away from incompatible substances. Do not store near alkaline substances. Store under an inert atmosphere.
B2 D1A D2B
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Ground and bond containers when transferring material. Do not get in eyes, on skin, or on 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. Do not ingest or inhale. Use only in a chemical fume hood. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
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.
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.
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. Remove all sources of ignition. Provide ventilation. A vapor suppressing foam may be used to reduce vapors. Water spray may reduce vapor but may not prevent ignition in closed spaces.
Stable under normal temperatures and pressures. Substance undergoes color change upon exposure to light and air.
Oxidizing agents, reducing agents, bases, acids (mineral, non-oxidizing, e.g. hydrochloric acid, hydrofluoric acid, muriatic acid, phosphoric acid), acids (mineral, oxidizing, e.g. chromic acid, hypochlorous acid, nitric acid, sulfuric acid), caustics (e.g. ammonia, ammonium hydrozide, calcium hydroxide, potassium hydroxide, sodium hydroxide).
Carbon monoxide, carbon dioxide.
Upper exp. limit, %
Lower exp. limit, %
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. Containers may explode when heated. Extinguishing media: For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. Use water spray to cool fire-exposed containers. Water may be ineffective. Do NOT use straight streams of water. For large fires, use dry chemical, carbon dioxide, alcohol-resistant foam, or water spray. Cool containers with flooding quantities of water until well after fire is out.
Very flammable. Combustion probable.
Flammable/combustible material; may be ignited by heat, sparks or flames. Vapor may travel to a source of ignition and flash back. Container may explode in heat of fire. Vapor explosion and poison hazard indoors, outdoors or in sewers. Runoff to sewer may create fire or explosion hazard. Readily converted by oxygen to hazardous peroxides and acids and is incompatible with caustics, ammonia, organic amines, mineral acids, and strong oxidizers. Readily resinifies to dimer when pure and slowly oxidizes to crotonic acid. Altered by light and air. Hazardous polymerization may occur. Polymerization may take place at high temperatures.
Fire will produce irritating, corrosive and/or toxic gases.
TLV: 2 ppm; 5.7 mg/m3 (as TWA) A3 (ACGIH 1997). MAK: class IIIB (1996) OSHA PEL: TWA 2 ppm (6 mg/m3) NIOSH REL: TWA 2 ppm (6 mg/m3) See Appendix C (Aldehydes) NIOSH IDLH: 50 ppm
2 (Very strong toxins)
Chronic inhalation may cause effects similar to those of acute inhalation.
Harmful if swallowed. Causes gastrointestinal tract burns.
Causes respiratory tract irritation. May cause irritation of the respiratory tract with burning pain in the nose and throat, coughing, wheezing, shortness of breath and pulmonary edema. Inhalation may be fatal as a result of spasm, inflammation, edema of the larynx and bronchi, chemical pneumonitis and pulmonary edema. Toxic if inhaled.
Causes skin irritation. May cause skin sensitization, an allergic reaction, which becomes evident upon re-exposure to this material. Substance is rapidly absorbed through the skin. Causes redness and pain.
Causes eye irritation. Contact with liquid or vapor causes severe burns and possible irreversible eye damage. Lachrymator (substance which increases the flow of tears). Causes redness and pain. Lachrymator (substance which increases the flow of tears).
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.
Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.
Get medical aid immediately. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Discard contaminated clothing in a manner which limits further exposure.
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately. Do NOT allow victim to rub or keep eyes closed.