IUPAC Name: Propa-1,2-diene ; Prop-1-yne
Synonyms: MAPP ; MAPP gas ; Methyl acetylene - propadiene mixture ; Methyl acetylene-allene mixture ; Methyl acetylene-propadiene mixture ; Propadiene-methyl acetylene ; Propyne, mixed with propadiene
CAS NO: 59355-75-8
Molecular Formula of Methyl acetylene-propadiene mixture (CAS NO.59355-75-8) : C₆H₈
Molecular Weight of Methyl acetylene-propadiene mixture (CAS NO.59355-75-8) : 80.12772
Molecular Structure of Methyl acetylene-propadiene mixture (CAS NO.59355-75-8) :
Mol File: 59355-75-8.mol
Enthalpy of Vaporization: 21.62 kJ/mol
Vapour Pressure: 4570 mmHg at 25°C

A flammable gas mixture. To fight fire, stop flow of gas. When heated to decomposition it emits acrid smoke and irritating fumes.

OSHA PEL: TWA 1000 ppm; STEL 1250 ppm
ACGIH TLV: TWA 1000 ppm; STEL 1250 ppm
DFG MAK: 1000 ppm (1650 mg/m³)
DOT Classification:  2.1; Label: Flammable Gas

1.General Description :Methylacetylene-propadiene stabilized is a colorless gas with an acetylene like odor. Methylacetylene and propadiene mixture,stabilized is shipped as a liquefied gas under its vapor pressure. Contact with the liquid can cause frostbite. Methylacetylene and propadiene mixture,stabilized is easily ignited. The vapors are heavier than air. Any leak can either be liquid or vapor. Methylacetylene and propadiene mixture,stabilized can asphyxiate by the displacement of air. Under prolonged exposure to fire or intense heat the containers may rupture violently and rocket.
2.Air & Water Reactions: Highly flammable.
3.Reactivity Profile: Methylacetylene-propadiene gas mixture presents a dangerous fire and explosion hazard when exposed to heat, flame or sparks or strong oxidizing agents. The liquid material in cylinders contains about 30% propadiene. Detonation may occur at 95°C . Reacts vigorously with strong oxidizing agents. Reaction with silver nitrate forms an acetylide igniting at 150°C. Violent explosions occurring at low temperatures in ammonia synthesis equipment have been traced to the addition products of dienes and oxides of nitrogen produced from the interaction of nitrogen oxide and oxygen.
4.Health Hazard: Simple asphyxiant. Toxicology of propadiene component not fully established. Contact with liquid may burn eyes and cause frostbite of skin.
5.Fire Hazard :Behavior in Fire: Containers may explode.