Decabromobiphenyl ether

First, thermal behaviour of decabromobiphenyl ether 1 will be described. The thermal reactivity of this compound depends on the applied conditions the pure compound reacts completely different in comparison to its reaction in polymeric matrices. Thermolysis of the pure compound gives a good yield (60 %) of hexabromobenzene. The main products obtained by incineration in th DIN oven at three temperatures for pure 1 and of 1 within a polypropylene matrix are shown in Table 1. 

Table 1. Main Products obtained by Incineration of Decabromobiphenyl ether 1 at three Different Temperatures Yields are in Percent by Weight (ref. 12)...

For the thermochemistry of pure decabromobiphenyl ether, the following mechanistic scheme has been suggested (Scheme 2) (ref. 11). 

Scheme 2. Proposed Mechanism for Thermolysis of Pure Decabromobiphenyl Ether (1)...

Thermochemistry in the polymeric matrix follows a different pattern. Decabromobiphenyl ether 1 does cyclize according to the following reaction yielding brominated dibenzofurans (PBDF). The optimal yield for PBDF depends on the applied burning temperature (refs. 14,15) this itself depends on the kind of polymeric matrix, which is shown below for incineration at the DIN-oven (Fig. 5). 

Fig. 5. Yields of Brominated Dibenzofurans from Decabromobiphenyl Ether as Dependent on Temperature and Amount of Sb203 (Synergist) in the Polymeric Matrix (Polybutylene-terephtalate).

Fig. 7. Influence of Various Metal Species on PBDD/F Concentrations during Incineration of Decabromobiphenyl ether in Polybutyleneterephtalate at 500°C (BIS-Furnace).

The difference in reactivity is not as much as is generally observed in nucleophilic aromatic substitution in solution by an addition-elimination mechanism (ref. 25). Substituents with electron withdrawing capabilities enhance the rate of the reaction therefore decabromobiphenyl ether reacts nearly 2 times faster than 1,2,3,4-tetrabromodibenzodioxin. 

Ambient air sampling on plant property of industrial bromine extraction and bromo-organics synthesis facilities revealed the presence of tetrabromobisphenol A (N.D. —28 ng/m ), decabromobiphenyl ether (N.D. —72 ng/m3), tris(2,3-dibromopro-pyljphosphate (N.D. —60 ng/m3) and l,2-bis(tribromophenoxy)ethane (N.D. —183 ng/m3). 

Releases of decabromobiphenyl ethers (DeBDEs) are required to be reported under the Superfund Amendments and Reauthorization Act (SARA) Section 313 consequently, data are available for this compound in the Toxic Release Inventory (TRI) (EPA 1995c). According to the TRI, a total of 865,109 pounds (392,407 kg) of DeBDE was released to the environment in 1999. In addition, an estimated 915,419 pounds (415,227kg) were transferred off-site, including to publicly-owned treatment works (POTW) (TRI99 2002). The TRI data should be used with caution because only certain types of facilities are required to report. This is not an exhaustive list. 

Lenior D, Zier B, Bieniek D, et al. 1994. The influenece of water and metals on PBDD/F concentration in incineration of decabromobiphenyl ether in polymeric matrices. Chemosphere 28(11) 1921-1928. 

Watanabe I, Tatsukawa R. 1987. Formation of brominated dibenzofurans from the photolysis of flame retardant decabromobiphenyl ether in hexane by UV and sun light. Bull Environ Contam Toxicol 39 953-959. 

DECABROMOBIPHENYL ETHER see PAU500 DECABROMOBIPHENYL OXIDE see PAU500 DECABROMODIPHENYL see PCC480 DECABROMODIPHENYL OXIDE see PAU500 DECABROMOPHENYL ETHER see PAU500 DECACHLOROKETONE see KEAOOO DECACHLORO-l,3,4-METHENO-2H-CYCLOBUTA(cd)PENTALEN-2-ONE see KEAOOO DECACHLOROOCTAHYDROKEPONE-2-ONE see KEAOOO... 

DECA Decabrom Decabrome Decabromobiphenyl ether Decabromo-biphenyl oxide Decabromodiphenyl ether. See Decabromodiphenyl oxide... 

Decabromobiphenyl ether Decabromobiphenyl oxide. See Decabromodiphenyl oxide Decabromodiphenylethane CAS 84852-53-9... 

Decabromodiphenyl ether. See Decabromodiphenyl oxide Decabromodiphenyl oxide CAS 1163-19-5 El NECS/ELINCS 214-604-9 Synonyms Bis (pentabromophenyl) ether DBDPO DECA Decabrom Decabrome Decabromobiphenyl ether ... 

Watanabe, I., Kashimoto, X, and Tatsukawa, R., Confirmation of the presence of the flame retardant decabromobiphenyl ether in river sediment from Osaka, Japan, Bull Environ. Contam. Toxicol, 36, 839,1986. 

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