Polybrominated styrene

Great Lakes offers Firemaster BP411, launched in 2004 for the manufacture of electrical connectors, relays and switches. Firemaster CP-44HF is a high-flow polybrominated styrene copolymer for polyesters and high temperature polyamides, while Fire Firemaster PBS 64HW is dibromostyrene-based. This type of FR is said to offer good thermal stability, flow and blister resistance. 

The replacement of established chemistries with newer ones is one of the classic drivers of change in the chemical industry. One of the current hotbeds of this kind of change is the replacement of brominated flame retardants in polymer formulations. The brominated flame retardants under the most scrutiny have been polybrominated diphenyl ethers, particularly penta- and octabromodiphenyl ether, which have been shown to be persistent in the environment and to bioaccumulate. Great Lakes Chemical is voluntarily phasing out penta- and octa-BDEs by the end of next year. The phaseout is made possible by the clean bill of health granted by EPA for Firemaster 550, a replacement for penta-BDE in flexible PU applications. BRG Townsend claims the phaseout of penta-BDE and octa-BDE is not as earth shattering as would be an exit from deca-BDE, a styrenics additive that is produced in the highest volume of the PBDEs. 

Indusfrial chemicals Cadmium Dioxin Lead Mercury Polybrominated biphenyls Polychlorinated biphenyls Pentachlorophenols Penta- to Nonylphenols Phthalates Styrenes... 

Brominated flame retardants (BFRs) are a structurally diverse group of compounds including aromatics, cyclic aliphatics, phenolic derivatives, ahphatics, and phthahc anhydride derivatives (Figure 31.3). The most common BFRs are tetrabromobisphenol A (TBBPA), polybrominated diphenyl ethers (PBDE), hexabromocyclododecane (HBCD), and polybrominated biphenyls (PBB). The primary use of TBBPA is as reactive additive in epoxy resin circuit boards, while decabromodiphenyloxide (DBDO) is primarily used in high impact polystyrene for electronic enclosures. PBDEs are typically used as the additive type of flame retardant in high impact polystyrene, acrylonitrile butadiene styrene, flexible polyurethane foam, textile coatings, wire and cable insulation and electrical connectors. 

Stainless steel Styrene-ethylene/butylene-styrene block copolymer automotive parts, small Polybrominated biphenyl automotive prods. 

The polybrominated diphenyl ethers (decabromodiphenyl ether, octabromodiphenyl ether) have been the most widely used of the brominated materials. These additives are cost efficient and are the conventional choice for high-impact polystyrene, ABS, and other styrenics. However, their use has been under challenge for environmental reasons. Other brominated species that cannot generate dioxin species under any conditions are now more in favour than PBDEs. 

Newer brominated materials from Dead Sea Bromine have been developed to allow the company non-polybrominated diphenyl ether (PBDE) options for a range of polymers, especially styrenic copolymers. 

There is evidence that children (from USA. U.K.) who are breast-fed may be exposed to a significant number of known toxic chemicals in breast milk, including methylene chloride, styrene, perchloroethylene, toluene, trichloroethylene, 1,1,1-trichloro-ethane, xylene, dioxins, benzene, polychlorinated biphenyls (PCBs), chloroform, and polybrominated diphenyl ethers (PBDEs). Over the last 30 years, the total PBDE levels in breast milk have doubled, especially during the past five years. The chemical "body burden" of males has slowly increased over this time period (Lyons, 1999 Lakind et al., 2004). 

It has better sunlight stability than the polybrominated diphenyl ethers and thus can be used in nonyellowing polyolefins and styrenics. By removal of a small impurity, Albemarle has made available a grade SAYTEX BT-93W with even better color photostability. 

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