Flame retardance polypropylene nanocomposites

He Q, Yuan T, Yan X, Ding D, Wang Q, Luo Z, Shen TD, Wei S, Cao D, Guo Z (2014) Flame-retardant polypropylene/multiwall carbon nanotube nanocomposites effects of surface functionalization and surfactant molecular weight. Macromol Chem Phys 215(4) 327-340 Heidari A, Beheshty MH, Rahimi H (2013) Functionalization of multi-walled carbon nanotubes via direct friedel-crafts acylation in an optimized PPA/P205 medium. Fuller Nanotubes Carbon Nanostruct 21(6) 516-524... 

Tang, Y., Hu, Y., Wang, Y.S., Gui, Z., Chen Z., and Fan, W. 2003. Intumescent flame retardant-montmorillonite synergism in polypropylene-layered silicate nanocomposites. Polym. Inter. 52 1396-1400. 

R. Kozlowski, M. Wladyka-Przybylak, and H. Rydarowski, Flammability of polypropylene/clay nanocomposites-synergism with some flame retardants, Proceedings of the 17th BCC Conference on Flame Retardancy, M. Lewin (Ed.), Business Communications Co Editions, Norwalk, CT, 2006. 

Polypropylene (PP) has wide acceptance for use in many application areas. However, low thermal resistance complicates its general practice. The new approach in thermal stabilization of PP is based on the synthesis of PP nanocomposites. This paper discusses new advances in the study of the thermo-oxidative degradation of PP nanocomposite. The observed results are interpreted by a proposed kinetic model, and the predominant role of the one-dimensional diffusion type reaction. According to the kinetic analysis, PP nanocomposites had superior thermal and fireproof behavior compared with neat PP. Evidently, the mechanism of nanocomposite flame retardancy is based on shielding role of high-performance carbonaceous-silicate char which insulates the underlying polymeric material and slows down the mass loss rate of decomposition products. 

Polypropylene nanocomposites have attracted more and more interest in flame retardant area in recent years due to their improved fire properties [18-20], It is suggested that the presence of clay can enhance the char formation providing a transient protective barrier and hence slowing down the degradation of the matrix [19,20],... 

Polymer/fullerene [Ceol nanocomposites can be considered environmentally friendly alternatives to some traditional flame retardants. The presence of Ceo can markedly delay thermal oxidative degradation and reduce the flammability of polypropylene at very low loadings. It can decrease the heat release rate of polymeric materials by trapping the free radicals created through thermal degradation and combustion, and subsequently forming three-dimensional gelled networks. This network can increase the melt viscosity and consequently slow down combustion. Furthermore, the incorporation of Qo does not affect the physical properties of the polymer. 

P. A. Song, H. Liu, Y. Shen, B. X. Du, and Z. P. Fang, Fabrication of dendrimer-like fullerene (Ceo) decorated oligomeric inmmescent flame retardant for reducing the thermal oxidation and flammability of polypropylene nanocomposites. Journal of Materials Chemistry, 19 (2009), 1305-13. 

Until 2003, Chen s [28], Qu s [29-31], and Hu s [32] groups independently reported nanocomposites with polymeric matrices for the first time the. In Hsueh and Chen s work, exfoUated polyimide/LDH was prepared by in situ polymerization of a mixture of aminobenzoate-modified Mg-Al LDH and polyamic acid (polyimide precursor) in N,N-dimethylactamide [28]. In other work, Chen and Qu successfully synthesized exfoliated polyethylene-g-maleic anhydride (PE-g-MA)/LDH nanocomposites by refluxing in a nonpolar xylene solution of PE-g-MA [29,30]. Then, Li et al. prepared polyfmethyl methacrylate) (PMMA)/MgAl LDH by exfoliation/adsorption with acetone as cosolvent [32]. Since then, polymer/LDH nanocomposites have attracted extensive interest. The wide variety of polymers used for nanocomposite preparation include polyethylene (PE) [29, 30, 33 9], polystyrene (PS) [48, 50-58], poly(propylene carbonate) [59], poly(3-hydroxybutyrate) [60-62], poly(vinyl chloride) [63], syndiotactic polystyrene [64], polyurethane [65], poly[(3-hydroxybutyrate)-co-(3-hydroxyvalerate)] [66], polypropylene (PP) [48, 67-70], nylon 6 [9,71,72], ethylene vinyl acetate copolymer (EVA) [73-77], poly(L-lactide) [78], poly(ethylene terephthalate) [79, 80], poly(caprolactone) [81], poly(p-dioxanone) [82], poly(vinyl alcohol) [83], PMMA [32,47, 48, 57, 84-93], poly(2-hydroxyethyl methacrylate) [94], poly(styrene-co-methyl methacrylate) [95], polyimide [28], and epoxy [96-98]. These nanocomposites often exhibit enhanced mechanical, thermal, optical, and electrical properties and flame retardancy. Among them, the thermal properties and flame retardancy are the most interesting and will be discussed in the following sections. 

Tang, Y. Hu, Y. Li, B. Lin, L. Wang, Z. Chen, Z. Fan, W. Polypropy-lene/montmorillonite nanocomposites and intumescent, flame-retardant montmorU-lonite synergism in polypropylene nanocomposites. J. Polym. Sci. A Polym. Chem. 

In 1976 Unitika Ltd, Japan, first presented the potential flame retardant properties of polyamide 6 (PA6)/layered silicate nanocomposites. However, not until more recent studies did the serious evaluation of the flammability properties of these materials begin when Gilman et al. reported detailed investigations on flame retardant properties of PA6/layered silicate nanocomposite. From this pioneering work many attempts have been made to study the flammability properties of polymer/layered silicate nanocomposites. A wide range of polymers has been employed to provide either intercalated or exfoliated nanocomposites, which exhibit enhanced fire retardant properties. These include various thermoplastic and thermosetting polymers, such as polystyrene (PS), high impact polystyrene (HIPS), poly(styrene-co-acrylonitrile) (SAN), acrylonitrile-butadiene-styrene (ABS), polymethyl methacrilate (PMMA), " polypropylene 14,15,19-22 polyethylene is, 19,23-27 poly(ethylene-... 

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