Triphenyl and tricresyl phosphates

Various phosphates are produced from phosphoric acid which is made either by adding sulphuric acid to phosphate rock (wet process) or by burning phosphorus in air to give phosphorus pentoxide, which is then hydrated. Major uses of phosphoric acid are the production of phosphate and compound fertilizers, formation of sodium tripolyphosphate (which is used as a builder in detergents where it forms stable water-soluble complexes with calcium and magnesium ions) and the production of organic derivatives like triphenyl and tricresyl phosphate. These are used as plasticizers for synthetic polymers and plastics. 

A wide variety of plasticizers are suitable for PVB and PVF resins. For many years, the universally used plasticizer for PVB was triethylene glycol di(2-ethylbutyrate) [95-08-9] (6). More recently this has been supplanted by triethylene glycol di(2-ethylhexanoate) [94-28-0], tetraethylene glycol diheptanoate [70729-68-9], dihexyl adipate [110-33-8], 2-ethylhexyl diphenyl phosphate [1241-94-7], and a variety of other oligomeric ethylene glycol esters and ethers, and other adipate, phosphate, phthalate, sebacate, and ricinoleate esters (19,20,57-62). For PVF, diethyl, diphenyl, and dicyclohexyl phthalates, as well as tributyl, triphenyl, and tricresyl phosphates are useful plasticizers (21). By proper choice of plasticizer type and level, the physical-mechanical, chemical, and adhesion properties of these resins can be tailored for a wide variety of applications (see Plasticizers). 

In poly(imide) (Pl)-based adhesive compositions that are particularly useful in flexible circuit applications, plasticizers are used (35). Organic phosphates in an amount from 15-35% are added, such as triphenyl and tricresyl phosphate. 

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