Tetraphenyl resorcinol diphosphate

Mixed esters, such as isopropylphenyl diphenyl phosphate and tcrt-butylphenyl diphenyl phosphate, are also widely used as both plasticizers/flame retardants for engineering thermoplastics and hydraulic fluids.11 These esters generally show slightly less flame-retardant efficacy, when compared to triaryl counterparts however, they have the added advantage of lower smoke production when burned. Some novel oligomeric phosphate flame retardants (based on tetraphenyl resorcinol diphosphate) are also employed to flame retard polyphenylene oxide blends, thermoplastic polyesters, polyamides, vinyls, and polycarbonates. 

Synonyms Phosphoric acid, 1,3-phenylene tetraphenyl ester Tetraphenyl resorcinol diphosphate... 

Tetraphenyl Resorcinol Diphosphate [57583-54-7], This is the main component of an oligomeric phosphate flame retardant, Akzo Nobel s FYROLFLEX RDP or Great Lakes Chemical s REOFOS RDP, designed for use in engineering thermoplastics such as polyphenylene oxide blends (105,106), thermoplastic polyesters, polyamides, polycarbonates, and ABS-polycarbonate blends. A major use was in PPO-HIPS blends and later in ABS-polycarbonate blends (107). It is a colorless to light-yellow liquid, viscosity 400-800 mPa s at 25°C, and a pour point of - 12°C. It is less volatile than the triaryl phosphates and has a higher percentage of phosphorus (11% P) than triphenyl phosphate. 

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