Flame retardant compounds

Gravesend, 2002, pp.2. 30cms. 25/4/2002 CATAPYRRIC SX545 CM540U SILANE CROSSLINKABLE LOW-SMOKE LOW-TOXICITY HALOGEN-FREE FLAME-RETARDANT COMPOUND, FOR INSULATION OF LV CABLES AND SHEATHING OF ALL TYPES OF CABLES AEI Compounds Ltd. 

ATH used in flame-retardant compounds precipitated silicates micas, wollastonite or calcium metasilicate barium sulphate, used for its opacity to X-rays and high density litho-pone quartz used in flour form. 

M.V. Troutman, R. Ravichandran, R. Kote, and R.E. King, Flame retarding compounds, US Patent 7531664, assigned to Ciba Specialty Chemicals Corporation (Tarrytown, NY), May 12,2009. 

Unmodified polyethylenes are flammable and are classified in the slow-burning category by the National Board of Fire Underwriters. Burning rate is approximately 1—1,5 inches (2.5—3.8 centimeters) per minute. The flammability of polyethylene may be retarded significantly by the addition of flame retardant compounds, such as antimony tnoxide along with halogenated compounds. 

The traditional halogen fire retardants used in styrenic copolymers are decabromodiphenyl ether and octabromodiphenyl ether, tetrabromobisphenol A, bis(tribromophenoxy) ethane, ethylene bis-tetrabromophthalimide, and chlorinated paraffins. Actually the octabromodiphenyl ether has been banned on precautionary principles, as will be explained below. The fire-retardant capabilities of the more effective halogen-containing compounds are in line with the quantity of halogen in the final polymer blend, with consideration for the use of synergists. Thus, the practical utility of these flame-retardant compounds (once the issue of degradation temperature is resolved) is often based on their ability to be blended into the polymer and to not substantially affect the physical properties of the polymers. 

The main reactive flame-retardant compounds used in unsaturated polyesters are tetrabro-mophthalic anhydride, dibromoneopentyl glycol, bis(2-hydroxyethyl) ether of tetrabromobisphenol A, and chlorendic anhydride. Tetrachlorophthalic anhydride is also used. 

Additive flame-retardant compounds include brominated epoxy resins, chlorinated hydrocarbons, decabromodiphenyl ether, and pentabromodiphenyl ether. Where transparency is not important, antimony oxide can be used as a synergist to reduce the amount of halogen required. 

Back-coating is the major area where bromine-based flame-retardant compounds are used for textiles. This technique is applied primarily in applications such as upholstery and wall coverings. The system would comprise an FR additive with a latex binder, the latter often based on acrylic or ethylene vinylacetate. Use of vinylidene chloride-modified acrylics reduce the amount of tire-retardant additive required. 

Layered Silicates Associated with Flame-Retardant Compounds.303... 

LAYERED SILICATES ASSOCIATED WITH FLAME-RETARDANT COMPOUNDS... 

Chen, T., Hendrix, A., Glogovski, T., and Butala, R., The characteristics of a non-halogen flame retardant compound using advanced thermoplastic elastomer, in Proceedings of the 51st IWCS/Focus International Wire Cable Symposium, Lake Buena Vista, FL, 2002, pp. 589-593. 

R.E. Alcock and J.S. Busby, Risk migration and scientific advance the case of flame retardant compounds, Risk Analysis, 2006, 26, 369. 

Figure 2.1 Chemical structures of major flame retardant compounds (a) polybrominated diphenyl ethers, (b) hexabromocyclododecane, (c) tetrabromobisphenol-A, (d) decabromo-dlphenyl ether (BDE209)...

Use Manufacture of carbon tetrachloride, trichloroethylene, chlorinated hydrocarbons, polychloro-prene (neoprene), polyvinyl chloride, hydrogen chloride, ethylene dichloride, hypochlorous acid, metallic chlorides, chloracetic acid, chlorobenzene, chlorinated lime water purification, shrinkproofing wool, flame-retardant compounds, special batteries (with lithium or zinc) processing of meat, fish, vegetables, and fruit. For information, refer to the Chlorine Institute, 2001 L St., NW, Suite 506, Washington DC 20036. 

In recent years there has been an effort to eliminate chlorine from all flame retardant compounds. Thus, there is a tendency to avoid the use of two of the most used additive flame retardants for fabrication of fire resistant PU TCEP and TCPP. This ban is dictated by the toxic and corrosive gases formed during combustion and from ecological point of view. 

The fire resistance of polyurethanes is based on the introduction of flame retardant compounds including polyols, containing chlorine, bromine or phosphorus in their structure. The polyols containing chlorine, bromine or phosphorus are linked chemically in the polyurethane structure and lead to self-extinguishing polyurethanes, with a permanent flame retardancy. 

MAJOR USES Used in the manufacture of carbon tetrachloride, trichloroethylene, chlorinated hydrocarbons, polychloroprene, polyvinylchloride, hydrogen chloride, hypochlorous acid, ethylene dichloride, metallic chlorides, chlorobenzene, chloroacetic acid, chlorinated lime, chloroform Used in the manufacturing process of water purification, flame retardant compounds, paper products, textiles, petroleum products, medicines, antiseptics, insecticides, solvents, paints, plastics, disinfectants, synthetic rubber. 

Based upon the principles of green chemistry and designed to evaluate the inherent hazards posed by chemicals, the Green Screen method proved to be useful in evaluating the hazards posed by decaBDE and the phosphorous-based flame retardants (and their breakdown products) and relatively simple to apply once the hazard endpoints and levels of concern were established. Of the three flame retardant compounds commonly used in TV enclosures and evaluated in the Green Screen, bisphenol A diphosphate (BRADP) and decaBDE only... 

To improve flame retardation in HIPS, agents formulated from halogenated compounds have been traditionally used [137, 138]. These compounds form, nevertheless, highly toxic vapors during the combustion process. Recently, alternative flame-retardant compounds have been developed, ensuring that no toxic vapors are expelled, presenting an augmented thermal stability. Furthermore,... 

Thermoset polyester Filled and reinforced materials Flame-retardant compounds... 

Just the ticket—new flame retardant compounds for the railways. Plastics Addit Compound [trade journal—Elsevier Ltd.] July/August 2008. 

Fire-retardant treatment Hammability of acrylic textiles can be reduced by using (meth)acrylates containing phosphorus monomers known to be effective as flame-retardant compounds (Price et al., 2002). Tsafack et al. (2004) smdied the plasma-grafted thin layer of phosphorus polymer by plasma-induced graft-polymerization. The formation of a characteristic protective char layer during the burning test was observed for the treated compounds whereas the untreated ones burned without residuals (Tsafack et al., 2004). 

Other chemical treatments may also be employed for more specific purposes for example, proprietary treatments, usually involving silicone or PTFE, enhance yam-to-yam or fibre-to-fibre lubricity during pulse or flex cleaning, and similarly, where flammability is a potential hazard, padding through commercially available flame retardant compounds may be necessary. 

Tributyl (tetradecyl) phosphonium chloride Tri (P,P -dichloroisopropyl) phosphate Trimethyl phosphate Triphenylphosphine oxide Tris-dibromopropylisocyanurate 4-Vinylcyclohexene Zeolite Zinc oxide Zirconium potassium hexafluoride flame retardant compounds Chlorine... 

Flexibilizers based on ethylene copolymer resin can be used to replace liquid plasticizers in flame retardant compounds. These flexibilizers substantially reduce smoke and help in retaining mechanical performance of PVC. " A new plasticizer was developed for flame retarded polyurethanes. " It is based on benzoate esters which are popular in PU application but a new plasticizer contains at least one (and up to four) bromine atoms in benzene ring. 

G. C. Tesoro, Chemical modification of polymers with flame-retardant compounds, Macromol. Revs. 13, 283 (1978). 

The flame-retardant properties of bromine and chlorine compounds are well known. Their effectiveness in a given situation appears to depend very much on the right choice of flame-retardant compound. Since these halogens are believed to exert their effect mainly in the form of hydrogen halide molecules, a great deal depends on the ease with which HCl or HBr is produced from the flame-retardant molecule under pyrolysis conditions. 

The flame-retardant compound must be stable enough to stand up to processing with the polymer, but not too stable to give up its halogen when the polymer burns. 

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