Flame retardant polymer nanocomposites with alumina as filler

Flame retardant polymer nanocomposites with alumina as filler 

ABDELGHANI LAACHACHl AND JOSE-MARIE LOPEZ CUESTA AMS - Centre de Recherche Public Henri Tudor CMGD - Ecole des Mines d Ales 

It has been reported that approximately 12 persons are killed and 120 are severely injured because of fire every day in Europe. Fire has considerable impact on the environment in terms of destmction of substructures and production of toxic and/or corrosive compounds such as CO, dioxins, HCN, and polycyclic aromatic compounds. Consequently, it is necessary to limit this kind of risk by designing new materials with improved flammability properties. Nowadays, many companies (building and civil engineering, transportation, cable-making and electrotechnical material, etc.) are directly concerned with this topic. 

Under these conditions, regulations impose the use of materials possessing thermal stability as well as efficient fire retardant properties. In parallel, emissions of smoke must be low, not very opaque, not very toxic, and not very corrosive. This evolution toward greater safety seriously limits the use of many materials and involves the rejection of solutions largely used so far and, in particular, halogen-based flame retardants, on account of environmental concerns. Moreover, analysis of various statistics on plastic consumption (180 MT/yr, with a global annual growth rate of approximately 8%) shows the economic importance of this field and illustrates the world s industrial stake in it. 

In this chapter we review the effects of hydrated and anhydrous alumina as filler on FR properties of polymer nanocomposites. Nanocomposites are particle-filled polymers for which at least one dimension of the dispersed particles is in the nanometer range. In the following sections, the mechanism and mode of action of nanometric alumina trihydrate (ATH), alumina monohydrate (AlOOH), and alumina (AI2O3) will be discussed. 

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