Answer: d) Cl or Br
There are many categories in which flame retardants can be
divided. The major categories among them include:
- Tetrakis (hydroxymethyl) phosphonium salts that are made by
passing phosphine gas through a solution of formaldehyde and a
mineral acid like hydrochloric acid. This category is mostly used
as flame retardants for textiles.
- Minerals like asbestos, compounds such as aluminum hydroxide,
magnesium hydroxide, antimony trioxide different hydrates, red
phosphorus, and boron compounds, mostly borates. Etc.
- Synthetic materials, usually halocarbons which include
organochlorines such as polychlorinated biphenyls (PCBs),
chlorendic acid derivates and chlorinated paraffins; organobromines
such as polybrominated diphenyl ether (PBDEs), organophosphates in
the form of halogenated phosphorus compounds and others.
To make it more simple, if we talk of the types of flame
retardants, they are:
- Brominated flame retardants
- Chlorinated flame retardants
- Phosphorous-containing flame retardants (Phosphate ester such
as Tri phenyl phosphate)
- Nitrogen-containing flame retardants (i.e. Melamines)
- Inorganic flame retardants.