Polymer stabilization fire retardants

It has been observed from the above discussion that mechanical, physico-chemical and fire retardancy properties of UPE matrix increases considerably on reinforcement with surface-modified natural cellulosic fibers. The benzoylated fibers-reinforced composite materials have been found to have the best mechanical and physico-chemical properties, followed by mercerized and raw Grewia optiva fibers-reinforced composites. From the above data it is also clear that polymer composites reinforced with 30% fibers loading showed the best mechanical properties. Further, benzoylated fibers-reinforced composites were also found to have better fire retardancy properties than mercerized and raw fibers-reinforced polymer composites. Fire retardancy behavior of raw and surface-modified Grewia optiva/GPE composites have been found to increase when fire retardants were used in combination with fibers. This increase in fire retardancy behavior of resulted composites was attributed to the higher thermal stability of magnesium hydroxide/zinc borate. 

Baneijee et al. reported a number of soluble poly-imido [134], polyazomethine [135], and polyazoxy phos-phonates [136] by the two phase polycondensation method with or without any phase transfer catalyst. Resulting polymers exhibit high thermal stability and fire retardancy. 

Literatures are available on POSS-polymer composites synthesized from different thermoplastics [71-74]. These composites are lightweight and show good fire retardancy, thermal stability, and mechanical reinforcement. Literatures on POSS-rubber composites are yet to come in a big way. 

L. Costa, G. Camino and L. Trossaarelli, "Thermal Degradation of Fire Retardant Chloroparaffin - Metal Compound Mixtures - Part I. Antimony Oxide,"Polym. Degradation and Stability, 5, 267 (1983). 

Borates, through their ability to act as glass network formers, can act as excellent char formers and drip suppressants in fire retardant applications. In many cases this involves processing into polymeric materials, leading to specific requirements for thermal stability and particle size. Most common borate materials, however, exhibit relatively low dehydration temperatures and may be unsuitable for use in many polymer systems. Zinc borates are often used because they have unusually high dehydration onset temperatures and can be produced as small particle size powders. 

Functionalized polymers are of interest in a variety of applications including but not limited to fire retardants, selective sorption resins, chromatography media, controlled release devices and phase transfer catalysts. This research has been conducted in an effort to functionalize a polymer with a variety of different reactive sites for use in membrane applications. These membranes are to be used for the specific separation and removal of metal ions of interest. A porous support was used to obtain membranes of a specified thickness with the desired mechanical stability. The monomer employed in this study was vinylbenzyl chloride, and it was lightly crosslinked with divinylbenzene in a photopolymerization. Specific ligands incorporated into the membrane film include dimethyl phosphonate esters, isopropyl phosphonate esters, phosphonic acid, and triethyl ammonium chloride groups. Most of the functionalization reactions were conducted with the solid membrane and liquid reactants, however, the vinylbenzyl chloride monomer was transformed to vinylbenzyl triethyl ammonium chloride prior to polymerization in some cases. The reaction conditions and analysis tools for uniformly derivatizing the crosslinked vinylbenzyl chloride / divinyl benzene films are presented in detail. 

The book opens with a paper on the structure and composition of wood to define the material under discussion and then considers molds, permeability, wood preservation, thermal deterioration and fire retard-ance, dimensional stability, adhesion, reconstituted wood boards such as fiberboard and particleboard, plywood, laminated beams, wood finishes, wood-polymer composites, and wood softening and forming. A final paper treats the common theme of wastewater management. Only one of the papers presented at the meeting is not included in this volume, and its subject of conventional wood preservation methods is adequately treated in detail elsewhere (e.g., Nicholas, D. D., Ed Wood Deterioration and Its Prevention by Preservative Treatments, 2 vols., Syracuse University Press, 1973). 

The purpose of fire-retardant systems is to reduce the heat supplied to the polymer below the critical level for flame stability. This can be achieved by modifying (generally decreasing) the rate of chemical or physical processes taking place in one or more of the steps of the burning process. 

Camino, G. Costa, L. Trossarelli, L. Thermal degradation of polymer-fire retardant mixtures Part III— Degradation products of polypropylene-chlorinated paraffin mixtures, Polymer Degradation and Stability, 1982,4(2), 133-144. 

Costa, L. Camino, G. Luda, M. P. Effect of the metal on the mechanism of fire retardance in chloroparaffin-metal compound-polypropylene mixtures, Polymer Degradation and Stability, 1986, 14(2), 113-123. 

Costa, L. Goberti, P. Paganetto, G. Camino, G. Sgarzi, P Thermal behaviour of chlorine-antimony fire-retardant systems, Polymer Degradation and Stability, 1990, 30(1), 13-28. 

Kaspersma, J. Doumen, C. Munro, S. Prins, A. M. Fire retardant mechanism of aliphatic bromine compounds in polystyrene and polypropylene, Polymer Degradation and Stability, 2002, 77(2), 325-331. 

Furthermore, the effect of hydrated fillers on polymer fire retardancy will depend not only on the nature of the filler, including its particle characteristics (size, shape, and purity) and decomposition behavior, but also on the degradation mechanism of the polymer, together with any filler/ polymer interactions that might occur, influencing thermal stability of the polymer and possible char formation. 

Marosi, Gy., Marton, A., Szep, A., Csontos, I., Keszei, S., Zimonyi, E., Toth, A., Almeras, X., and Le Bras, M. 2003. Fire retardancy effect of migration in polypropylene nanocomposites induced by modified interlayer. Polymer Degradation and Stability 82(2) 379—385. 

Duquesne, S., Le Bras, M., Jama, C., Weil, E.D., and Gengembre, L. 2002. X-ray photoelectron spectroscopy investigation of fire retarded polymeric materials Application to the study of an intumescent system. Polymer Degradation and Stability 77(2) 203-211. 

A. Laachachi, E. Leroy, M. Cochez, M. Ferriol, and J.M. Lopez-Cuesta, Use of oxide nano-particles and organoclays to improve thermal stability and fire retardancy of PMMA, Polym. Degrad. Stabil., 2005, 89 344. 

G. Marosi, A. Marton, A. Szep, I. Czontos, S. Keszei, E. Zimonyi, A. Toth, X. Almeras, and M. Le Bras, Fire retardancy effect of migration in PP nanocomposites induced by modified interlayer, Polym. Degrad. Stabil., 2003, 82 379-385. 

G. Chigwada, P. Jash, D.D. Jiang, and C.A. Wilkie, Fire retardancy of vinyl ester nanocomposites Synergy with phosphorus-based fire retardants. Polym. Degrad. Stabil., 2005, 89 85-100. 

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