Flame retardants boron-based

Q Boron-Based Flame Retardants and Flame Retardancy... 

Boron compounds such as borax and boric acid are well-known fire retardants in cellulosic products and coatings.12 However, the use of boron compounds such as zinc borate, ammonium pent-aborate (APB), melamine borate, boric oxide, boron phosphate, and other metal borates in polymers has become prominent only since early 1980s.3 6 This chapter will review the chemical and physical properties, the end-use applications, as well as the mode of actions of major boron compounds as fire retardants in different applications. Since boron-based flame retardants are extensively used and quoted in literature, only those formulations of commercial importance and representative literature examples will be discussed and/or cited in this chapter. 

Boron-based fire retardants have a wide spectrum of applications. They are multifunctional fire retardants. They can function as flame retardants, smoke suppressants, afterglow suppressants, and anti-tracking agents. 

For more than a decade potential environmental problems associated with organo-bromine flame retardant systems have motivated the search for non-halogen-based approaches to reduce polymer flammability. Initially, research focused on development of new phosphorus-based flame retardants, and numerous publications and patents have been issued in this area. Similarly motivated research has also produced nonhalogen flame retardant approaches based on other elements, such as boron and sihcon. At the same time, work on the use of additives, or flllers, with nanometer-scale primary particle sizes, produced polymer nanocomposites. These materials exhibit enhancement in a variety of physical properties at one-tenth the loading required when micrometer-size additives are used. ... 

Major Boron-Based Commercial Flame Retardants... 

Some of the inorganic compounds, snch as antimony trioxide (Sb203), or boron-based componnds, snch as zinc borate, fnnction as synergists rather than directly as flame retardants bnt enhance the effectiveness of the latter. Antimony trioxide is used mainly with halogenated flame retardants. 

The chemistry of flame-retardant additives is highly varied and is optimised not only for specific polymer chemistries, but also to address flammability effects such as flame spread, dripping, smoke release and so on. Flame-retardant chemistry includes classes of compounds such as halogenated organics, char formers, crosslinking compounds, mineral fillers, intumescent packages, phosphorus compounds, nitrogen-based compounds and even certain metal and boron compounds. 

Kilinc Mert, Cakal Gaye O., Bayram Goknur, Eroglu Inci, and Ozkar Saim. Flame retardancy and mechanical properties of pet-based composites containing phosphorus and boron-based additives. J. Appl. Polym. Sci. 132 no. 22 (2015) 42016-42021. 

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