Thermal properties epoxy nanocomposites

As mentioned above that high resolution TGA was used to check the purity of the filler so that no local bilayer of the excess surface modification molecules is present in the filler. The commercially treated fillers, however, are often observed to contain an excess of surface modification molecules [16]. This excess can lead to unwanted interactions with the epoxy prepolymer or can thermally degrade at lower temperatures when composites are subjected to higher temperatures thus, the presence of such excess amount is not required. In order to underline the effect of the excess surface modification molecules on the filler surface on the composite properties, epoxy nanocomposites with a number of commercially pro-... 

Incorporation of monofunctional epoxy POSS into an amine-cured epoxy network increased and broadened the Tg without changing the crosslink density and enhanced the thermal properties. Additionally, it was found that the thermal and thermal-mechanical properties of resultant styrene-POSS vinylester resin nanocomposites were dependent on the percentage of POSS incorporated into the resin [171]. Over a range of POSS incorporations, the Tg of the copolymers changed very little, but the flexural modulus increased with increasing POSS content. 

Chen, J. -S., Pohks, M. D., Ober, C. K., Zhang, Y., Wiesner, U., and Giannelis, E., Study of the interlayer expansion mechanism and thermal-mechanical properties of surface-initiated epoxy nanocomposites. Polymer, 43, 4895-4904 (2002). 

Ale Alessi, S., Conduruta, D., Pitarresi, G., Dispenza, C., Spadaro, G. Accelerated ageing due to moisture absorption of thermally cured epoxy resin/polyethersulphone blends Thermal, mechanical and morphological behaviour. Polym. Degradation Stability 96 (2011) 642-648. llAsi Asif, A., Rao, V. L., Ninan, K. N. Preparation, characterization, thermo-mechanical, and barrier properties of exfoliated thermoplastic toughened epoxy clay ternary nanocomposites. Polym. Adv. Technol. 22 (2011) 437 47. 

Considering the low physical characteristics of biopolymers, fillers are recommended for the reinforcement of their electrical, mechanical and thermal properties. Following the discovery of CNT, much work has been done regarding their application as fillers in other polymers, for improving the properties of the matrix polymer. At first CNT were used as a filler in epoxy resin, by the alignment method. Later on, numerous studies have focused on CNT as excellent substitutes for conventional nanofillers in nanocomposites and recently, many polymers and biopolymers have been reinforced by CNT. As already mentioned, these nanocomposites have remarkable characteristics, compared to the bulk materials, due to their imique properties. 

Reddy, C. S., Patra, P. K., and Das, C. K. 2009. Ethylene-octene copolymer-nanosilica nanocomposites Effects of epoxy resin functionalized nanosilica on structural, mechanical, dynamic mechanical and thermal properties. Macromolecular Symposia 277 119-129. 

The thermal properties of the nanocomposites of diglycidyl ether of bisphenol A epoxy resin containing different montmorillonite nanoclays depends on the surface modifications of the nanoclays. Moreover, the addition of nanoclays improved the thermal properties of the nanocomposites, compared to the neat epoxy [59]. 

The effects of Cloisite loading on the thermal decomposition behavior of an epoxy resin were reported by Ingram et al. [65]. It was shown that the addition of Cloisite in the systems improved the thermal stability of the epoxy resins which underwent an initial cure at 180 °C. However, when the nanocomposites were post cured at 220 °C, the nanoclay incorporation induced a decrease in the thermal stability of the systems. This behavior may be attributed to the dissociated alkyl chains, which destabilize the thermal properties after being subjected to high temperatures [66]. Therefore, a carefid selection of cure and post cure temperatures must be made in order to obtain nancomposites with improved physical properties and with enhanced thermal stability. 

The incorporation of 5 % organically modified sepiolite, which is a microcrystalline-hydrated magnesium silicate, in a bisphenol A-based epoxy resin has no significant effect over the thermal stability of the epoxy resin, due to the poor dispersion of the clay and poor diffusion of the resin between fibres [69]. The effect of attapulgite (magnesium aluminium phyllosilicate) over the thermal properties of hyperbranched polyimides was studied. The presence of this silicate in the nanocomposites significantly improved the thermal stability of the neat polyimide [70]. 

Nagendiran, S., Alagar, M., Hamerton, I. Octasilsesquioxane-reinforced DGEBA and TGDDM epoxy nanocomposites Characterization of thermal, dielectric and morphological properties. Acta Mater. 58, 3345-3356 (2010)... 

Yang, K., Gu, M. The Effects of triethylenetetramine grafting of multi-walled carbon nanotubes on its dispersion, filler-matrix interfacial interaction and the thermal properties of epoxy nanocomposites. Polym. Eng. Sci. 49, 2158-2167 (2009)... 

Li, Y., Pan, D., Chen, S., Wang, Q., Pan, G., Wang, T. In situ polymerization and mechanical, thermal properties of pol5mrethane/graphene oxide/epoxy nanocomposites. 

Gabr, M. H., Phong, N. T., Okubo, K., Uzawa, K., Kimpara, 1., Fujii, T. (2014). Thermal and mechanical properties of electrospun nano-celullose reinforced epoxy nanocomposites., 51-58. 

Significant efforts have been directed toward performance enhancements of epoxy structural composites. Advances have been made in the epoxy-toughening area. Epoxy nanocomposites and nanotube systems have been studied and are claimed to bring exceptional thermal, chemical, and mechanical property improvements. However, commercialization has not yet materialized. 

Zainuddin S, Hosur MV, Zhou Y, Narteh AT, Kumar A, Jeelani S. Experimental and numerical investigations on flexural and thermal properties of nanoclay-epoxy nanocomposites. Mater Sci Eng A 2010 527 7920-7926. 

Russ M, Rahatekar SS, Koziol K, Parmer B, Peng H-X (2013) Length-dependent electrical and thermal properties of carbon nanotube-loaded epoxy nanocomposites. Compos Sci Technol 81 42 7... 

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. 

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