Smoke suppression INDEX

Details are given of the addition of flame retardant and smoke suppressant additives to PVC to meet specifications such as oxygen index, heat release, smoke evolution or extent of burning in cable tests. Data are presented for synergistic combinations of additives in PVC formulations. 31 refs. 

CAS 21645-51-2 EINECS/ELINCS 244-492-7 Uses Flame retardant, smoke suppressant filler in polymeric materials incl. PVC, thermosets, elastomeric copolymers, rubber, latex, paints, wire and cable, coatings, paper, and adhesives Properties Dry, free-flowing powd. 4-6 p median particle size 0.1% on 325 mesh sp.gr. 2.42 bulk dens. 40 Ib/fP Ooose), 70 Ib/fP (packed) brightness (Hunter Y) 92-94 ref. index 1.57 KC-750 [Georgia Marble]... 

CAS 21645-51-2 EINECS/ELINCS 244-492-7 Uses Smoke suppressant, flame retardant, filler for PVC and XLPE wire/ cable insulation, SBR compds., epoxies, silicones, elastomers, neoprene foam, vinyl sheet flooring, adhesives, coatings, paints, polishes Pn rerties Superfine powd. 3.5 p avg. particle diam. sp.gr. 2.42 surf, area 8 m /g oil absorp. 32 brightness (TAPPI) 95 ref. index 1.57 hardness (Mohs) 2.5-3.5... 

Chem. Descrip. Zinc borate CAS 1332-07-6 EINECS/ELINCS 215-566-6 Uses Flame retardant, smoke suppressant for plastisols, coatings for cellulosics, textiles, and adhesives synergist in PVC and halogenated polyester formulations, and in elastomers, thermoplastic elastomers, polyamides, and polyolefins strong char promoter Properties Wh. free-flowing powd., nonhygroscopic 6 p avg. particle size 99.9% < 30 p sol. 0.5 g/100 ml water sp.gr. 2.50 bulk dens. 18.1 Ib/ff oil absorp. 39 ref. index 1.48 Zb -237 [Great Lakes]... 

In the cable industry, plasticization of CPVC by phthalates and phosphates improves the flexibility and processability of CPVC. However, the addition of plasticizer lowers the limiting oxygen index and increases smoke production. The schematic diagram below illnstrates the mechanism of degradation in the absence (A) and the presence (B) of the smoke-suppressing componnd - basic iron oxide, FeOOH. " ... 

In addition to flame-retardancy, zinc borates have a smoke suppressing effect. When used in polyamides, they counteract the reduction in the tracking index (cf. Section 3.2.2.1) caused by the halogenic flame-retardants. ... 

Keywords flame retardancy, flame retardants, flammability, ignition, oxygen index, UL-94, cone calorimeter, burning rate, smoke suppression, intumescent coating, fire proofing, char formation, rate of heat release. 

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. 

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