Bisphenol-A tetrabromo

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. 

COMPARISON OF HEPATOTOXICITY OF MONOBROMOBENZENE, DIBROMOBENZENES, HEXABROMOBENZENE AND TETRABROMO-BISPHENOL A... 

Voordeckers JW, DE Fennell, K Jones, MM Haggblom (2002) Anaerobic biotransformation of tetrabromo-bisphenol-A, tetrachlorobisphenol-A, and bisphenol A in estuarine sediments. Environ Sci Technol 36 696-701. 

The challenge was to avoid the use of hazardous brominated fire retardants such as polybrominated biphenyl (PBB) and pentabromodiphenyl ether (PBDE). The first strategy was to replace PBB and PBDE with tetrabromo-bisphenol-A (TBBA). This has a much lower toxicity, but is still a brominated fire retardant with safety concerns. An improvement... 

Saegusa Y, Fujimoto H, Woo GH, Inoue K, Takahashi M, Mitsumori K, Hirose M, Nishikawa A, Shibutani M (2009) Developmental toxicity of brominated flame retardants, tetrabromo-bisphenol A and 1,2,5,6,9,10-hexabromocyclododecane, in rat offspring after maternal exposure from mid-gestation through lactation. Reprod Toxicol 28 456-467... 

Fire resistant polymers were obtained from brominated epoxynovolak resin, BPA/DC prepolymer, BMI, Zn acetate and benzoyl peroxide [103] or from an oligo-aspartimide (BMI-diamine reaction product), BPA/DC, 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane (i.e. Tetrabromo-Bisphenol A) and 2-ethyl-4-methylimi-dazole [104]. A mixture of BPA/DC, BMI and epoxide resin with brominated polycarbonate, copoly[oxy-2,6-dimethylphenylene)-(oxy-2,3,6-trimethylphenylene)] and a catalyst was also suggested [105],... 

In electronic encapsulation applications, epoxy derivatives of novolacs containing meta-bromo phenol have exhibited substantially better physical and performance properties compared to the conventional tetrabromo bisphenol-A epoxies and brominated epoxy novolacs. The meta-bromo phenol moiety contributes the expected improvements in thermal and hydrolytic stability to the formulation while providing fire retardancy properties (13). 

Epoxy molding compounds, used to encapsulate microelectronic devices, contain bromine to provide flame retardancy to the package. This bromine, typically added as tetrabromo bisphenol-A or its epoxy derivative, has been found to contain many hydrolyzable bromides. These bromides, along with the presence of chloride impurities, are detrimental to the life of the electronic component. Bromine especially has been suspected (proven) to cause wire bond failure when subjected to moisture and/or high temperatures. With the addition of a more thermally and hydrolytic stable bromine compound, flame retardancy does not have to be compromised to increase the device reliability. Stable brominated cresol epoxy novolac, when formulated into a microelectronic encapsulant, increases the reliability of the device without sacrificing any of the beneficial properties of present-day molding compounds. 

Thomsen, C., Lundanes, E., and Becher, G., A simplified method for determination of tetrabromo-bisphenol A and polybrominated diphenyl ethers in human plasma and semm, J. Sep. Sci., 24, 282-290, 2001. 

A third category of vinyl ester resin is formed when tetrabromo bisphenol-A (TBBA) is used in the manufacture of the base epoxy starting resin. This affords a resin with up to about 20wt% bromine bound into its structure and is designed to achieve good fire retardancy. An added advantage of the bromine is that because of the large size of bromine atoms, it improves the chemical resistance, particularly towards caustic and hypochlorite solutions [1]. 

Brominated PS is combined with antimony trioxide as a flame retardant [70]. In addition, brominated polyCphenylene ether) has been used. Other flame retardants are tetrabromocyclooctane, tetrabro-movinylcyclohexene, or bis-(allyl ether) tetrabromo-bisphenol A. Eor the latter flame retardants, dicumyl peroxide is added as a synergist [71] and the additives are used together with blowing agents. 

Organic Bromine. This is an efficient flame retardant that can be greatly syner-gized by addition of antimony trioxide. Since aliphatic bromine is too unstable for plastic processing, preferred compounds are polybrominated diphenyl ethers for thermoplastics, and tetrabromo bisphenol A and tetrabromophthalic anhydride for epoxies and polyesters. In a fire, it does produce smoke and toxic corrosive gases, so this must be considered in specific applications. In Europe, environmental concerns may limit the use of bromine. 

Tetrabromo bisphenol A 79-94-7 544 58 181 High reactivity and efficiency PC, epoxy, phenolic, ABS... 

Epoxy molding compounds are made flame retardant with tetrabromo-bisphenol A as the reactive intermediate in manufacturing the epoxy compound. Rigid polyvinyl chloride (PVC) usually does not require flame retardants because of its high chlorine content. However, flexible PVC will use retardants such as antimony oxide, zinc borate, and chlorinated paraffins and phosphate esters. ATH can also be used in compounds that tolerate fillers and is typically combined with antimony oxide and phosphate esters. 

Decarbromopheny oxide ether Tetrabromo-bisphenol A Pentahromodiphenyl oxide)... 

Bis(2,3-dibromopropyl ether) of tetrabromo-bisphenol A Polyolefins Melt-blendable for optimum physical properties... 

The question of the flammability behavior of similar flame retarding structures when used as additives or as comonomers in PET is discussed. For the case of structures related to tetrabromo-bisphenol-A, there was little difference, but for those containing triphenylphosphine oxide related structures a switch from volatile phase to condensed phase mechanisms was possible. 

Chapter 7 discussed flame retardants in more detail. The key point to be made here is that the most common flame retardant used in base materials, tetrabromo-bisphenol-A (TBBPA), is not restricted by RoHS. Furthermore, in FR-4 materials,TBBPA is generally reacted into one of the epoxy resins, and thus does not exist as a free-standing molecule, but is incorporated into the molecular backbone of the resin system. 

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