Decabromodiphenyls

Suggested formulations for various polymers using hexabromocyclododecane (HBCD), a brominated aHphatic a chlorinated paraffin, ie, a chlorinated aHphatic and decabromodiphenyl oxide, a brominated aromatic, are shown in Tables 2—4. These suggested formulations may not be strictiy comparable because of differences in the nature of the base resins. However, the suggestions are specific to a given UL-94 rating. 

Decabromodiphenyl oxide contains approximately 83% bromine. For flame retardants having a lower bromine content, the use level must be raised accordingly. 

DecabromodiphenylOxide. Decabromodiphenyl oxide [1163-19-5] (decabrom) is the largest volume bromiaated flame retardant used solely as an additive. It is prepared by the bromination of diphenyl oxide ia neat bromine usiag AlCl as a catalyst (32). The bromination may also be carried out ia an iaert solvent such as methylene dibromide [74-95-3] (33). The commercially available grades are >98% decabromodiphenyl oxide with the remainder being the nonabromo species. 

The Brominated Flame Retardants Industry Panel (BFRIP) was formed ia 1985 within the Flame Retardant Chemicals Association (FRCA) to address such concerns about the use of decabromodiphenyl oxide. Siace 1990 the BFRIP has operated as a Chemical Self-Funded Technical Advocacy and Research (CHEMSTAR) panel within the Chemical Manufacturers Association (CMA) (64). As of 1993, members of BFRIP are Ak2o, Amerihaas (Dead Sea Bromine Group), Ethyl Corp., and Great Lakes Chemical. Siace its formation, BFRIP has presented updates to iadustry on a regular basis (65,66), and has pubhshed a summary of the available toxicity information on four of the largest volume brominated flame retardants (67,68) tetrabromo bisphenol A, pentabromodiphenyl oxide, octabromodiphenyl oxide, and decabromodiphenyl oxide. This information supplements that summarized ia Table 11. 

Research sponsored by BFRIP regarding the use of brominated flame retardants shows that there is no evidence that the use of decabromodiphenyl oxide leads to any unusual risk. In addition, a study by the National Bureau of Standards (now National Institute of Science and Technology) showed that the use of flame retardants significantly decreased the ha2ards associated with burning of common materials under reaUstic fire conditions (73). Work ia Japan confirms this finding (74). 

In the 1990s, two types of flame retardants are preferred for outdoor fabrics, ie, a system based on phosphoms and nitrogen such as the precondensate—NH finish and an antimony—bromine system based on decabromodiphenyl oxide [1163-19-5] and antimony(III) oxide (20,40—42). 

Decabromodiphenyl Oxide—Polyacrylate Finishes. An alternative to the diffusion technique is the appHcation of decabromodiphenyl oxide on the surface of fabrics in conjunction with binders (131). Experimental finishes using graft polymerization, in situ polymerization of phosphoms-containing vinyl monomers, or surface halogenation of the fibers also have been reported (129,130,132,133). 

Flame Retardants. Flame retardants are added to nylon to eliminate burning drips and to obtain short self-extinguishing times. Halogenated organics, together with catalysts such as antimony trioxide, are commonly used to give free-radical suppression in the vapor phase, thus inhibiting the combustion process. Some common additives are decabromodiphenyl oxide, brominated polystyrene, and chlorinated... 

Specific identity of a toxic chemical to be a trade secret, the notice to your customer(s) must contain a generic chemical name that Is descriptive of the structure of that toxic chemical. For example, decabromodiphenyl oxide could be described as a halogenated aromatic. 

Dead Sea Bromine Group, 177 Dead Sea Magnesium Ltd., 177 Decaborane, 49 Decabromodiphenyl ether, 49 DECP, 50... 

Figure 12.3 Clrromatogr-ams of an ignition-resistant high-impact polystyrene sample (a) Microcolumn SEC fi ace (b) capillary GC trace of peak x . Peak identification is as follows 1, ionol 2, benzophenone 3, styrene dimer 4, palmitic acid 5, stearic acid 6, styrene trimers 7, styrene trimer 8, styrene oligomer 9, Irganox 1076 and Irganox 168 10, styrene oligomer 11, nonabromodiphenyl oxide and 12, decabromodiphenyl oxide. Reprinted with permission from Ref. (12).

It should be mentioned that fire retardant-polypropylene has higher impact energy than polypropylene without HBCD and this improved impact energy resulting from the addition of fire retardant is a rare phenomenon. Usually the addition (15-25%) of low molecular components decreases the high impact properties of plastics although we know that HIPS flame-retarded with decabromodiphenyl oxide (DECA), for example, has almost the same impact energy as non-retarded HIPS (Table 5). 

Fig. 6. Yield and Distribution Pattern of PBDF formed from Incineration of Decabromodiphenyl Ether in Polybutyleneterephtalate with 5,5 % Sb203 at 6 different Temperatures. 

It is possible that brominated dibenzodioxins and -furans are formed in trace levels during the preparation of technical bromoether products 1-2- Dumler (ref. 12) and others (ref. 17) have found PBDD/F in the ppm range in commercial samples of decabromodiphenyl ether. A more recent and advanced study has been... 

The brominated organic compounds are used as either additive (e.g. decabromodiphenyl, hexabromobenzene, pentabromotoluene), or reactive flame retardants (e.g. tetrabromobisphenol-A, tri- and pentabromophenols). The major... 

Anaerobic dehalogenation has also been observed in aromatic ethers including polychlorinated dibenzo[l,4]dioxins (Fennell et al. 2004 Yoshida et al. 2005). The anaerobic debromination of decabromodiphenyl ether is considered here since it is analogous to the dehalogenation of polyhalogenated biphenyls. 

Gerecke AC, PC Hartmann, NV Heeb, H-PE Kohler, W Giger, P Schmid, M Zennegg, M Kohler (2005) Anaerobic degradation of decabromodiphenyl ether. Environ Sci Technol 39 1078-1083. 

Similarly, toluene suspensions of the polystyrene housing of TV sets were examined by means of TPPy-FTMS (300-1200 K) [224], Diphenylether (DPE) was evidenced by peaks at m/z 141, 142 and 170 and decabromobiphenyl (DBBP) by m/z 943 and 864. Decabromodiphenyl ether (DBDPE) was recognised by thermal degradation products around m/z 800... 

EPA IRIS, Integrated risk information system regarding decabromodiphenyl ether, octabromo-diphenyl ether and pentabromodiphenyl ether)... 

These models have been applied to different scenarios, mainly for two chemicals DeBDE (decabromodiphenyl ether) and Pb (lead). The input data to the models are based on the SFA investigations described above. 

There is a huge variety of PBDEs considering that there might be from one to ten bromine atoms bound to the diphenyl ether molecule. Among all the PBDEs, the commercial mixtures of decabromodiphenyl ether (deca-BDE), octabromodiphenyl ether (octa-BDE) and pentabromodiphenyl ether (penta-BDE) are the products that are most found in the environment. Related to octa-BDE and penta-BDE mixtures, their commercial use was banned in the European Union in 2004 and that year their leading manufacturers in North America stopped producing them on a voluntary basis [2], Regarding the deca-BDE mixture, since July 2008, its use has been... 

The third composition in Table IV seems to be related to the aromatic sulfonate/polycarbonate technology just discussed with some modifications being necessary in order to compensate for the aliphatic nature of the polypropylene (17. 181 substrate. In this case the aromatic sulfonate is replaced with a metal salt (preferably magnesium stearate). A silicone oil and or gum has been added to enhance the intumescent character and a small amount of inert filler and decabromodiphenyl oxide is included probably to improve the molding characteristics of the total composition. Fire retardant compositions with a good surface char can be obtained at total loadings only about half that required for the halogen/antimony oxide composition. 

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