Molecular basis of flame inhibition

Abstract

The role played by inorganic c he mi cal additives in fire retardancy and flam e inhibition is considered. Particular attention is given to the molec ular level aspects of co mm ercially important systems containing co mpound s of antimony, halogens, and phosphorus. The flam e inhibiting function of metal containing additives is also discussed.

Application of Nanocomposites to Floor Sheet for Railway Vehicle

“…Poly(vinyl chloride) (PVC) is one such material which can be used in railway vehicles. However, halogen compounds produce toxic gas, mainly acid gases, in combustion [2]. In recent years, there has been growing concern that the toxic gas produced during combustion endangers railway passengers.…”

“…In the light of this experience, it has become imperative to produce and use halogen-free polymeric materials which are not only sufficiently flame resistant but also as low cost as PVC. However, improving the flame resistance of polymeric materials using ordinary inorganic flame retardants, such as Al(OH) 3 and Mg(OH) 2 , would be required in large amounts, adding approximately 50 wt%. The concern is therefore that the advantages of using such types of polymeric materials would be spoiled by the increase in density and brittleness.…”

Synthesis and thermal analytical screening of metal complexes as potential novel fire retardants in polyamide 6.6

“…50 wt%). 1, 2, 9, 10 Many metal oxides such as ZnO, Fe2O3 and SnO can provide an inherent degree of flame retardancy in some polymers, 7, 9, 11 while others, such as antimony trioxide, Sb2O3 (ATO), zinc hydroxystannate, (ZHS) and zinc stannate (ZnSnO3, or ZnSn(OH)6 (ZS) can act in concert with phosphorus or halogen flame retardants, 8,9,[12][13][14][15][16][17][18][19] and, in the case of the last example, can additionally display smoke suppression activity. 14,15 Many inorganic synergists, however, display little or no interaction with their host polymer due to their chemical inertness, lack of viable reaction pathway with their host polymer or specific reaction mechanism with any primary flame retardant present.…”

Mechanical properties of flame retardant filled polypropylene composites

“…This is mainly due to the synergism between the halogenated compounds and antimony oxide to form volatile antimony halides that act as free radicals trapped around the flame. 2 However, such types of FRs are not thermally stable; they generate toxic gases and corrosive smokes during combustion or high temperature processing. 3 In relation to this, use of halogenbased FRs has given rise to some environmental concern.…”

“…Among the non-halogen-based FRs, magnesium hydroxides [Mg(OH) 2 ] have been studied in detail and represent the most popular replacements for halogen-based FRs. The mechanisms of Mg(OH) 2 as a FR are totally different from that of a halogen-based FR.…”