Retardant polymer

The assessment of the contribution of a product to the fire severity and the resulting hazard to people and property combines appropriate product flammabihty data, descriptions of the building and occupants, and computer software that includes the dynamics and chemistry of fires. This type of assessment offers benefits not available from stand-alone test methods quantitative appraisal of the incremental impact on fire safety of changes in a product appraisal of the use of a given material in a number of products and appraisal of the differing impacts of a product in different buildings and occupancies. One method, HAZARD I (11), has been used to determine that several commonly used fire-retardant—polymer systems reduced the overall fire hazard compared to similar nonfire retarded formulations (12). 

Continual use of decabromidiphenyl oxide has been placed ia question based on the discovery that under certain laboratory conditions brominated dibenzo- -dioxias are generated (63). The condition most often employed ia such studies is pyrolysis of milligram-scale samples at 600°C. This temperature is higher than polymer processiag conditions and lower than fire temperatures, ie, the conditions are not representative of actual conditions to which flame-retardant polymers are exposed. 

E. D. Weil, Proc. Rec. Adv. Flame Retard. Polym. Matter, (L. Menachem, ed.), I Business Communication Co., Norwalk, Connecticut (1990). 

The history of polymer fire retardance is reviewed from its inception with the early Egyptians to the most recent developments in intumescent fire retardants and inherently fire retardant polymers. 

FIRE RETARDANT FILLERS. The next major fire retardant development resulted from the need for an acceptable fire retardant system for such new thermoplastics as polyethylene, polypropylene and nylon. The plasticizer approach of CP or the use of a reactive monomer were not applicable to these polymers because the crystallinity upon which their desirable properties were dependent were reduced or destroyed in the process of adding the fire retardant. Additionally, most halogen additives, such as CP, were thermally unstable at the high molding temperatures required. The introduction of inert fire retardant fillers in 1965 defined two novel approaches to fire retardant polymers. 

A Novel System for the Application of Bromine in Flame-Retarding Polymers... 

In addition to this reaction, quinones and other alkyl radical acceptors retard polymer oxidation by the reaction with alkyl radicals (see earlier). As a result, effectiveness of these inhibitors increases with the formation of hydroperoxide groups in PP. In addition, the inhibiting capacity of these antioxidants grows with hydroperoxide accumulation. The results illustrating the efficiency of the antioxidants with cyclic chain termination mechanisms in PP containing hydroperoxide groups is presented in Table 19.12. The polyatomic phenols producing quinones also possess the ability to terminate several chains. 

Used industrially as a chemical intermediate in the manufacture of pesticides and phos-phosilicate glass. Used as a gasoline additive, catalyst, and as a fireproofing agent in the production of textiles and flame-retardant polymers for polyurethane foams. 

Poly (vinyl chloride) occurs as a colourless rigid material. It is having a high density and low softenting point. It is also having a higher dielectric constant and power factor. The high chlorine content of poly (vinyl chloride) makes it flame retardant polymers. 

A. L. Higginbotham, J. R. Lomeda, A. B. Morgan, J. M. Tour, Nanocomposite, Graphite oxide flame-retardant polymer, ACS Appl Mater Interfaces, vol. 10, pp. 2256-2261, 2009. 

Morgan, A.B. and Wilkie, C.A. 2007. Flame Retardant Polymer Nanocomposites. Wiley, Hoboken, NJ. Nelson, G. and Wilkie, C.A. 2001. Fire and Polymers. Oxford University Press, New York. 

Antimony trioxide (Sb203) and pentoxide (Sb205) are both used in combination with halogen compounds for flame retarding polymers. Their manufacture properties and use have been described by Touval [109]. The trioxide is the predominate form for use in thermoplastics. 

Dumler R, Lenoir HTD, Hutzinger O. 1989a. OBDF and PBDD from the combustion of bromine containing flame retarded polymers A survey. Chemosphere 19(12) 2023-2031. 

Riess M, Ernst T, Popp R, et al. 2000. Analysis of flame retarded polymers and recycling materials. Chemosphere 40(9-11) 937-941. 

D. Hoang, J. Kim, and B.N. Jang, Synthesis and performance of cyclic phosphorus-containing flame retardants, Polym. Degrad. Stab., 93(11) 2042-2047, November 2008. 

A fire retardant polymer that is easily impregnated into wood to petrify the material, making it stronger and nonflammable. 

Fig. 18. Arrhenius-plot of the rate constants kg for the retarded polymer transfer from the gel into the sol (full lines), and ks for the corresponding reversible-thermodynamic equilibrium in that transport (dashed lines), see Fig. 17...

Both terms on the right-hand side of this equation are always non-negative the quantity In (kg/k ) increases with decreasing temperature for any P, as can be seen from Table 5 or Fig. 18 e.g. the values 0.06 at 27 °C and 1.32 at 15 °C are obtained for P = 1082 according to Table 5. The second term is even greater than the first (reversible) one at low column temperatures it represents the irreversible part of the heat of transfer gel -> sol in the flow-equilibrium proposed. Thus, both terms can be considered as the activation enthalpy of the retarded polymer rediffusion from the gel into the sol ... 

Wolf M, Riess M, Heitmann D, et al. 2000. Application of a purge and trap TDS-GC/MS procedure for the determination of emissions from flame retarded polymers. Chemosphere 41 693-699. 

The pH sensitivity of halloysite can be enhanced by using retardant polymers, a cationic coating for the formation of a pH-sensitive polyelectrolyte shell on the nanotubes after their saturation with corrosion inhibitor. To equip the halloysite nanotubes with controlled release properties, the surface of the nanotubes was first loaded with benzotriazole and subsequently modified by LbL deposition of two polyelectrolyte bilayers, thus blocking the tubes openings with polyelectrolytes. 

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