triphenylfosfaatti

Triphenyl phosphate (triphenylfosfaatti in Finnish) is an organophosphate ester with the formula C18H15O4P. It consists of a phosphorus(V) center double-bonded to an oxygen and bonded to three phenoxy groups (OC6H5). At room temperature it is a colorless to pale-yellow viscous liquid with low vapor pressure and is practically insoluble in water, but soluble in many organic solvents.

Production and structure: Triphenyl phosphate is typically prepared by esterification of phosphoric acid or phosphorus oxychloride with phenol, often in the presence of a base or dehydrating catalyst. The reaction yields the triaryl phosphate and inorganic byproducts such as HCl or water, depending on the route.

Applications: The principal use of triphenyl phosphate is as a flame retardant for polymers, particularly polyvinyl chloride (PVC) and polyurethanes, and as a plasticizer in coatings, adhesives, and cellulose esters. It can improve fire resistance and modify rheological properties of formulations. It is also used in some hydraulic fluids and lubricants in formulated products.

Properties and safety: Triphenyl phosphate has low volatility, which reduces some inhalation exposure compared with more volatile additives. It can act as an irritant to skin and eyes and may be harmful if swallowed. Environmental concerns include persistence and potential toxicity to aquatic life, leading to regulatory scrutiny in some regions. Proper handling, storage, and waste disposal in accordance with safety guidelines are advised.