Brominated flame retardant
Brominated flame retardants (BFRs) are
Types of compounds
Many different BFRs are produced synthetically with widely varying chemical properties. There are several groups:[1]
- PentaBDE(not manufactured anymore, the first BFR, commercialized in the 1950s)
- Polybrominated biphenyl (PBB), not manufactured anymore
- Brominated cyclohydrocarbons
- Other brominated flame retardants with different properties and mechanisms
Hexabromocyclododecane (HBCD or HBCDD) is a ring consisting of twelve carbon atoms with six bromine atoms tied to the ring. The commercially used HBCD is in fact a mixture of different isomers. HBCD is toxic to water-living organisms. The UNEP Stockholm Convention has listed HBCD for elimination, but allowing a temporary exemption for the use in polystyrene insulation foams in buildings.[3]
Tetrabromobisphenol A (TBBPA or TBBP-A) is regarded as toxic to water environment.[citation needed] This flame retardant is mainly used in printed circuit boards, as a reactive. Since TBBPA is chemically bound to the resin of the printed circuit board, it is less easily released than the loosely applied mixtures in foams such that an EU risk assessment concluded in 2005 that TBBPA poses no risk to human health in that application.[4] TBBPA is also used as an additive in acrylonitrile butadiene styrene (ABS).
Contents in plastics
Content of brominated flame retardants in different polymers:[5]
Polymer | Content [%] | Substances |
---|---|---|
Polystyrene foam | 0.8–4 | HBCD |
High impact polystyrene
|
11–15 | DecaBDE, brominated polystyrene |
Epoxy resin
|
0-0.1 | TBBPA |
Polyamides | 13–16 | DecaBDE, brominated polystyrene |
Polyolefins | 5–8 | DecaBDE, propylene dibromo styrene |
Polyurethanes | n/a | No brominated FR available |
Polyterephthalate | 8–11 | Brominated polystyrene |
Unsaturated polyesters | 13–28 | TBBPA |
Polycarbonate | 4–6 | Brominated polystyrene |
Styrene copolymers | 12–15 | Brominated polystyrene |
Production
390,000 tons of brominated flame retardants were sold in 2011. This represents 19.7% of the flame retardants market.[6]
Types of applications
The electronics industry accounts for the greatest consumption of BFRs. In computers, BFRs are used in four main applications: in printed circuit boards, in components such as connectors, in plastic covers, and in electrical cables. BFRs are also used in a multitude of products, including, but not exclusively, plastic covers of television sets, carpets, pillows, paints, upholstery, and domestic kitchen appliances.
Testing for BFR in plastics
Until recently testing for BFR has been cumbersome. Cycle time, cost, and level of expertise required for the test engineer has precluded the implementation of any screening of plastic components in a manufacturing or in a product qualification/validation environment.
Recently, with the introduction of a new analytical instrument
In February 2009, the
Environmental and safety issues
Many brominated chemicals are under increasing criticism in their use in household furnishings and where children would come into contact with them. Some believe PBDEs could have harmful effects on humans and animals. Increasing concern has prompted some European countries to ban some of them, following the
Some brominated flame retardants were identified as
See also
References
- ^ The European Commission (9 February 2017). "Commission Regulation (EU) 2017/227". Official Journal of the European Union. L35: 6–9. Retrieved 16 June 2017.
- ^ The final decision is available on the UNEP Stockholm Convention website here: "COP Decisions". Archived from the original on 2014-09-25. Retrieved 2014-10-26.
- ^ "EU Risk Assessment Report of 2,2',6,6'-tetrabromo-4,4'-isopropylidenediphenol (tetrabromobisphenol-A or TBBP-A) Part II – human health" (PDF). Institute for Health and Consumer Protection. Archived from the original (PDF) on 2014-09-05. Retrieved 2014-10-26.
- ^ Pedro Arias (2001): Brominated flame retardants – an overview. The Second International Workshop on Brominated Flame Retardants, Stockholm
- ^ Townsend Solutions Estimate, "Flammschutz Online - the flame retardants market". Archived from the original on 2016-03-04. Retrieved 2014-10-26.
- Seattle Post Intelligencer.
- PMID 12515688. Archived from the originalon 2008-11-01.
- ^ "Polybrominated Diphenyl Ethers (PBDEs) Action Plan Summary | Existing Chemicals | OPPT | US EPA". Archived from the original on 2015-09-01. Retrieved 2012-12-03.
- ^ "Brominated Flame Retardants in the Environment" (PDF). Columbia Environmental Research Center. Archived (PDF) from the original on 2016-05-08. Retrieved 2012-12-03.
- ^ "European Union Risk Assessment Report of diphenyl ether, pentabromo deriv". Institute for Health and Consumer Protection. 2000. Archived from the original on 2014-10-26. Retrieved 2014-10-26.
- ^ "European Union Risk Assessment Report of diphenyl ether, octabromo deriv". Institute for Health and Consumer Protection. 2003. Archived from the original on 2014-10-26. Retrieved 2014-10-26.
Further reading
- Kyle D'Silva, Alwyn Fernandes & Martin Rose (2004). "Brominated Organic Micropollutants—Igniting the Flame Retardant Issue". Critical Reviews in Environmental Science and Technology. 34 (2): 141–207. S2CID 95008650.
- Law, Robin J.; Kohler, Martin; Heeb, Norbert V.; Gerecke, Andreas C.; Schmid, Peter; Voorspoels, Stefan; Covaci, Adrian; Becher, Georg; Janak, Karel (2005). "Hexabromocyclododecane Challenges Scientists and Regulators". Environmental Science & Technology. 39 (13): 281A–287A. PMID 16053062.
- Cynthia A. de Wit (2002). "An overview of brominated flame retardants in the environment". PMID 11999784.
- Young Ran Kim; et al. (2014). "Health consequences of exposure to brominated flame retardants: A systematic review" (PDF). PMID 24529398.
- H. Fromme; G. Becher; B. Hilger; W. Völkel (2016). "Brominated flame retardants – Exposure and risk assessment for the general population". PMID 26412400.
- J. de Boer; H. M. Stapleton (2019). "Toward fire safety without chemical risk". S2CID 121618800.
External links
- MPI Milebrome - Brominated Flame Retardants
- Bromine Science and Environmental Forum
- European Brominated Flame Retardant Industry Panel
- SFT: Current State of Knowledge and Monitoring requirements: Emerging "new" Brominated flame retardants in flame retarded products and the environment[permanent dead link]