Isobutane is a colourless flammable gas without odour. It is an easily liquefied hydrocarbon of the alkane class. It is highly soluble in organic solvents such as water, ethers, esters and alcohols, and it can easily transit to a liquidphase. Like some other grades of liquefied hydrocarbon gases, isobutane is used for extruded polystyrene, foamedpolyethylene and polypropylene, polyurethane foams andcorrosion preventive compounds and adhesives forsoundproofing, waterproofing solutions, and vapourbarriers.