MAPP gas was a trademarked name, belonging to The Linde Group, a division of the former global chemical giant Union Carbide, for a fuel gas based on a stabilized mixture of methylacetylene (propyne), propadiene and propane. The name comes from the original chemical composition, methylacetylene-propadiene propane. "MAPP gas" is also widely used as a generic name for UN 1060 stabilised methylacetylene-propadiene (unstabilised methylacetylene-propadiene is known as MAPD).
MAPP gas was widely regarded as a safer and easier-to-use substitute for acetylene, but, early in 2008, its production was discontinued at the only remaining plant in North America that still manufactured it. However, there are many MAPP substitutes on the market, often labeled "MAPP" but containing mostly propylene with some propane and in some cases also dimethyl ether.[1] [2]