A Review of the Role of Basic Iron(III) Oxide Acting as a Char Forming/Smoke Suppressing/Flame Retarding Additive in Halogenated Polymers and Halogenated Polymer Blends

Abstract

The char forming/smoke suppressing action of an inorganic iron(III) compound in halogenated polymers is reviewed. Basic iron(III) oxide is known to enhance the formation of carbonaceous char via a series of cross-linking reactions catalysed by the insitu formation of reactive iron(III) Lewis acids, which results in a substantial reduction in the amount of smoke produced when these polymers are forced to burn in air. The effects of this iron(III) compound acting as a flame retardant are also discussed, although it is less clear how the compound functions as an active flame retardant in these chlorinated polymers.