Retardant fillers calcium hydroxide

Since NBR/PVC has basic good flame resistance it may be used in hose and belt applications where this is a requirement. A 70/30 or 50/50 NBR/PVC base elastomer should be selected and use non-black fillers, including alumina trihydrate (e.g.. Hydrated Alumina 983), magnesium hydroxide, and zinc borate (e.g., Firebrake ZB) as flame retardant fillers. Calcium carbonate will assist in reducing smoke emission. In addition a phosphate plasticizer such as Kronitex 100 or chlorinated paraffin like Chlorowax 40 should be used as the only plasticizer types. 

Western-world bauxite production in 1988 totaled about 90 x 10 t, approximately 90% of which was refined to aluminum hydroxide by the Bayer process. Most of the hydroxide was then calcined to alumina and consumed in making aluminum metal. The balance, which constituted about 2.3 x 10 t in 1988 (Table 2), was consumed in production of abrasives (qv) adhesives (qv) calcium aluminate cement used in binding ceramics (qv) and refractories (qv) catalysts used in petrochemical processes and automobile catalytic converter systems (see Petroleum Exhaust control, automotive) ceramics that insulate electronic components such as semiconductors and spark plugs chemicals such as alum, aluminum halides, and zeoHte countertop materials for kitchens and baths cultured marble fire-retardant filler for acryhc and plastic materials used in automobile seats, carpet backing, and insulation wrap for wire and cable (see Flame retardants) paper (qv) cosmetics (qv) toothpaste manufacture refractory linings for furnaces and kilns and separation systems that remove impurities from Hquids and gases. 

There has been growing demand for nonhalogen, low smoke polymers for wire and cable insulation and sheathing. These products can be polyolefins with nonhalogen flame retardants, often metal hydroxides. DuPont markets a maleated compatibiliser under the name Fusabond to compatibilise polyolefins with the inorganic flame retardants, ATH and magnesium hydroxide, as well as with mineral fillers like calcium carbonate. 

Other reactions might be postulated the subject is worth further investigation. Calcium carbonate, in fine particle grades, notably reduces hydrogen chloride emission during combustion. At least one grade, Ultracarb , is sold for this purpose. It is often used in combination with flame-retardant fillers such as ATH and magnesium hydroxide. 

Antimony trioxide and chlorinated paraffinic derivatives are common materials used as fire retardants, as are intumescent zinc (or calcium) borate, aluminium hydroxide and magnesium hydroxide. These inorganic materials, used as bulk fillers, act to reduce the fire hazard. Halogenated materials release chlorine, which then combines with the antimony trioxide to form the trichloride, which is a flame suppressant. 

Magnum-White. [RMc Minerals] Magnesium hydroxide/calcium carbonate blend fire retardant smoke suppressant filler for PVC compds., SBR-latex formulations. 

The effectiveness of intumescent flame retardants is frequently reduced when fillers are added. Interactions can be either chemical or physical. Materials which are basic in character such as aluminium and magnesium hydroxides and calcium carbonate tend to interfere chemically with the phosphoric acid precursor in the intumescent system, presumably forming inorganic phosphates. Such antagonistic behaviour can be easily recognized by an almost complete lack of char formation. 

In order to consider effective strategies for the recovery and reuse of plastics recyclates, a quantitative method is described for the characterisation of polyester-based moulding compounds. Analytical procedures are described for the quantification of fibre, filler and fire retardant contents in polyester moulding compounds containing calcium carbonate filler, glass fibre reinforcement, and aluminium hydroxide flame retardant. 3 refs. 

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