Bisphenol A bis diphenyl phosphate

The flame retardant mechanism of PC/ABS compositions using bisphenol A bis(diphenyl phosphate) (BDP) and zinc borate have been investigated (54). BDP affects the decomposition of PC/ABS and acts as a flame retardant in both the gas and the condensed phase. The pyrolysis was studied by thermogravimetry coupled with fourier transform infrared spectroscopy (FUR) and nuclear magnetic-resonance spectroscopy. Zinc borate effects an additional hydrolysis of the PC and contributes to a borate network on the residue. 

K.H. Pawlowski, B. Schartel, M.A. Fichera, and C. Jager, Flame retar-dancy mechanisms of bisphenol A bis(diphenyl phosphate) in combination with zinc borate in bisphenol a polycarbonate/acrylonitri-le-butadiene-styrene blends, Thermochim. Acta, In Press, Accepted Manuscript, 2009. 

Zinc borate in PC/ABS and polyamide—when zinc borate is used in conjunction with bisphenol-A-bis-diphenyl phosphate in PC/ABS, it was reported that borophosphate and zinc phosphate were generated during polymer combustion.111 The formation of these materials could be beneficial for passing the more stringent Are tests, such as UL-95 5 V. When Firebrake 500 is used in conjunction with aluminum diethylphosphinate and melamine polyphosphate in polyamide, Schartel et al. reported the formation of boron aluminum phosphate in the condensed phase.112... 

Flame retardants that are often nsed in polycarbonate/ABS plastics (such as in compnter indnstry) include nonhalogen triaryl phosphates, such as RDP [resorcinol bis (diphenyl phosphate)] and BDP [bisphenol A bis(diphenyl phosphate)]. As BDP has lower phosphorus content compared to that of RDP, more of it should be used to match the flammability performance of RDP. In one particular study using polycar-bonate-ABS alloy, 9% of RDP or 12.3% of BDP was employed and showed equal to each other and excellent flame retardant properties [8]. 

Fyrolflex BDP from Akzo Nobel Chemicals has been shown to exhibit higher thermal properties and hydrolytic stability than other aryl phosphates, and to provide similar or better fire retardant performance than RDP. It is a bisphenol A bis(diphenyl phosphate) compound that provides good physical properties in formulations based on PC/ABS, HIPS and polyphenylene oxide/HIPS blends. Upon thermal decomposition of the flame-retarded polymers, phosphorus tends to accumulate in the solid residue, a result which indicates that the primary FR action of BDP is most likely to be in the condensed phase. 

Pawlowski KH, Schartel B. Flame retardancy mechanisms of triphenyl phosphate, resorcinol bis(diphenyl phosphate) and bisphenol a bisfdiphenyl phosphate) in polycarbonate/acrylonitrile-butadiene-styrene blends. Polym. Int. 2007 56 1404-1414. 

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