Diphenyl oxide (DPO) is a colorless liquid, which emits floral odor at temperatures of 80ºF (27ºC) and above. It is a white, crystalline solid at temperatures below 80ºF (27ºC). DPO has low volatility, low solubility in water, and is stable at high temperatures. It belongs to the family of aromatic homomonocyclic compounds. DPO is also recognized by the names,OxydibenzeneDiphenyl ether, Diphenyl oxide, 1,1′-Oxybisbenzene, and Phenoxybenzene. DPO can be used individually or as a mixture with other materials. It can also be used as a raw material or chemical intermediate to produce commercial products because of its reactivity. DPO is used as heat transfer media – used for heating industrial processes, alkylated diphenyl oxides – used to make surfactants, greases and lubricants, halogenated diphenyl oxides – used in insecticides, wood preservatives, and flame retardants for appliance casings in consumer electronic products, high temperature solvents, coatings, textile dye labeling, plastics – like ethylene-propylene-diene monomer (EPDM) rubber that is used for membrane roofing materials.
Diphenyl ether is used in alcoholic beverages. It is present in Muscat grapes, green tea, vanilla, lemon balm, buckwheat, potato chips, and grilled beef. Decabromodiphenyl oxide is used as a flame retardant in the manufacture of paints and reinforced plastics. Diphenyl ether is used widely in soap perfumes as well as its stability and low price due to its stability and low price. Its odor akin to that of scented geranium. Diphenyl ether is also used in the production of polyesters. DPO is easily reactive with oxidizing materials.
It can be used as a heat transfer medium when mixed with biphenyl. This mixture is used as heat transfer medium due to its high temperature range. Production of polyamide and polyimide also involves the use of diphenyl oxide when used in the production of phenoxathiin. Several polybrominated diphenyl ethers (PBDEs) are useful flame retardants. Of penta-, octa-, and decaBDE, the three most common PBDEs, only decaBDE is still in widespread use since its ban in the European Union in 2003.