Boron-Containing Fire Retardants

There is litde information on the health effects of long-term exposure to boron. Most of the studies are on short-term exposures. The Department of Health and Human Services, the International Agency for Research on Cancer, and the US Environmental Protection Agency (EPA) have not classified boron with regard to its human carcinogenicity. One animal study found no evidence of cancer after lifetime exposure to boric add in food. No human studies are available [102]. 

Zinc borate is also used commonly as a Are retardant. The toxicity of zinc is low [103] and data indicate that relatively large amounts of zinc may pass for years through the kidneys and gastrointestinal tract in humans without causing any detectable dinical damage [104]. Some zinc salts are irritants and corrosive on skin contad and when ingested they can act as emetics [105]. 

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Table 9.2 lists the properties and applications for major boron-containing fire retardants. 

Gonoshilov, D. G., Keibal, N. A., Bondarenko, S. N., Kablov, V. F. (2010). Phosphorus Boron Containing Fire Retardant Compounds for Polyamide Fibers Proceedings of the 16th International Scientific and Practical Conference Rubber industry Raw materials. Manufactured materials. Technologies, Moscow, 160-162. 

Table 2 lists properties of and applications for various types of boron-containing fire retardants. 

Boric acid is also an important precursor of other boron-containing fire retardants. 

Previously, it was found that phosphorus boron containing compounds are effective antipyrenes in a fire retardant composition [5-7],... 

Fire resistant PU are obtained by the addition or by introduction into the PU structure of special compounds, called flame retardants. The flame retardants are organic compounds containing halogens (chlorine, bromine) and phosphorus. Compounds of antimony (Sb) or boron [1-13] are rarely used. Sometimes inorganic compounds are used as flame retardants for PU, such as, hydrated alumina (Al203 nH20), Sb203 or ammonium polyphosphate [1-3, 14]. 

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