Flame retardants iron compounds

Flame retardants iron compounds, their effect on fire and smoke in halogenated polymers ... 

Iron oxides have been shown to be good smoke suppressants in various systems. They also seem to be effective flame retardants when used in conjunction with a halogen source. (They are discussed more fully in the separate entries Smoke suppressants and Flame retardants iron compounds, their effect on fire and smoke in halogenated polymers. )... 

However, adding 5% hydrated iron(iii) oxide to the above formulation increases char formation from 6% to 20%, at 650°C, and reduces smoke emission by over 50% [2]. The most effective iron compounds investigated to date appear to be the oxides, although some organometaUic compounds of iron such as ferrocene are active in PVC. (See also the entry entitled Flame retardants iron compounds, their effect on fire and smoke in halogenated pol)oners for more detail.) See also Figure 1. 

In 1990, appioximately 66,000 metric tons of alumina trihydiate [12252-70-9] AI2O2 3H20, the most widely used flame retardant, was used to inhibit the flammabihty of plastics processed at low temperatures. Alumina trihydrate is manufactured from either bauxite ore or recovered aluminum by either the Bayer or sinter processes (25). In the Bayer process, the bauxite ore is digested in a caustic solution, then filtered to remove siUcate, titanate, and iron impurities. The alumina trihydrate is recovered from the filtered solution by precipitation. In the sinter process the aluminum is leached from the ore using a solution of soda and lime from which pure alumina trihydrate is recovered (see Aluminum compounds). 

Flame retardant - [ALUMENUMCOMPOUNDS - ALUMINUM SULFATE AND ALUMS] (Vol 2) - [AMMONIUMCOMPOUNDS](Vol2) - [VINYL POLYMERS - VINYL CHLORIDE POLYMERS] (Vol24) -ethyleneimines [IMINES, CYCLIC] (Vol 14) -filler for [LEAD COMPOUNDS - LEAD SALTS] (Vol 15) -iron compounds as [IRON COMPOUNDS] (Vol 14) -magnesium hydroxide as filler [MAGNESIUMCOMPOUNDS] (Vol 15)... 

Flame retardants - [TEXTILES-FINISHING] (Vol 23) - [ALUMENUMCOMPOUNDS - INTRODUCTION] (Vol2) -antimony as [ANTIMONY AND ANTIMONY ALLOYS] (Vol 3) -antimony compds as [ANTIMONY COMPOUNDS] (Vol 3) -antimony compds as [ANTIMONY COMPOUNDS] (Vol 3) -based on ammonium sulfamate [SULFAMIC ACID AND SULFAMATES] (Vol 23) -bromine in [BROMINE] (Vol 4) -in electronic applications [PACKAGING - ELECTRONIC MATERIALS] (Vol 17) -iron fluoride in mfg of [FLUORINE COMPOUNDS, INORGANIC - IRON] (Vol 11) -nickel compounds as [NICKEL COMPOUNDS] (Vol 17) -phosphorus for [PHOSPHORUS] (Vol 18) -polycarbonates in [POLYCARBONATES] (Vol 19) -from propylene oxide [PROPYLENE OXIDE] (Vol 20) -for rubbers [RUBBERCHEMICALS] (Vol 21) -use m electrical connectors [ELECTRICAL CONNECTORS] (Vol 9)... 

Special considerations presence of zinc, copper, iron and nickel compounds accelerated dehydrochlorination combination of basic magnesium carbonate and aluminum hydroxide is used as flame retardant and smoke supressant chlorinated polyethylene adsorbs on the surface of titanium dioxide forming a layer 1-20 nm thick depending on the aciii/base interaction parameter of titanium dioxide ... 

Iron compounds have been tested as flame retardants. 

The purpose of this section is to give an up to date overview of the effects which some iron compounds have on flammability and smoke production when polymers burn in air. A glance at chemical abstracts indexes under iron, iron compounds or iron chemistry shows thousands of scientific papers appearing every year however, very few of these deal with the use of iron compounds as flame retarding/smoke suppressing additives for polymers. The recent chemistry of iron has been reviewed by Silver [1] but again there are few comments on the potential uses of iron compounds in polymers. 

Keywords tin, tin oxide, zinc hydroxystannate, zinc stannate, organotin compounds, antimony trioxide, alumina trihydrate, magnesium hydroxide, titanium dioxide, molybdenum trioxide, iron oxide, zinc borate, alumina, halogenated flame retardants, metal halides, thermal analysis, Mossbauer spectroscopy, fire-retardant mechanism, ultrafine powders, coated fillers. 

The use of plasticizers that are themselves flame retardants is discussed in Chapter 9, as well as formulating so as to optimize their effect and to minimize their tendency to be less efficient than flammable plasticizers. Chapter 9 also considers combustion mechanisms. A useful review of the latter has been given by Green. This chapter presents the use of inorganic additives as flame retardants and smoke suppressants as a basis for formulation for specific applications. These additives can be divided into antimony compounds and derivatives the class of metal hydroxides, carbonates, and basic carbonates and a further range of molybdenum, zinc, and iron compounds. 

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