Epoxy resins, layered silicate nanocomposites

Gilman, J.W., Kashiwagi, T., Nyden, M., Brown, J.E.T., Jackson, C.L., Lomakin, S., Giannelis, E.P., and Manias, E., Flammability studies of polymer layered silicate nanocomposites Polyolefin, epoxy, and vinyl ester resins, in Chemistry cmd Technology of Polymer Additives, Al-Malaika, S., Golovoy, A., and Wilkie, C.A., (Eds.), Blackwell Science, Oxford, U.K., 1999, Chapter 14, pp. 249-265. 

Becker, O., Cheng, Y.-B., Varley, R. J., and Simon, G. R, Layered silicate nanocomposites based on various high functionality epoxy resins the influence of cure temperature on morphology, mechanical properties and free volume, Macmmolecules, 36,1616-1625 (2003). 

In this article, recent developments in the formation and properties of epoxy layered silicate nanocomposites are reviewed. The effect of processing conditions on cure chemistry and morphology is examined, and their relationship to a broad range of material properties elucidated. An understanding of the intercalation mechanism and subsequent influences on nanocomposite formation is emphasized. Recent work involving the structure and properties of ternary, thermosetting nanocomposite systems which incorporate resin, layered silicates and an additional phase (fibre, thermoplastic or rubber) are also discussed, and future research directions in this highly active area are canvassed. 

As most work reported to date on thermosetting layered silicate nanocomposites involves epoxy resins, this review will focus on this class of thermosetting materials. However, some work pubUshed on other thermosets such as vinyl ester resins and imsaturated polyesters will be included where appropriate. 

Fig. 6 Small-angle x-ray characterization of epoxy layered silicate nanocomposites synthesized using n-CioH2iNH3-montmorillonite (SCIO), Shell Epi-Cure curing agent (W) and Shell Epon 862 resin where q is the scattering vector [47]...

J. W. Gilman, T. Kashiwagi, M. Nyden, J. E. T. Brown, C. L. Jackson, S. Lomakin, E. P. Giannelis, and E. Manias, Elammability studies of polymer layered silicate nanocomposites Polyolefin, epoxy and vinyl ester resins. In Chemistry and Technology of Polymer Additives, ed. S. Al-Malaika, A. Golovoy, and C. A. Wilkie (Malden Black-well Science, 1999), pp. 249-65. 

Gilman, J.W. Kashiwagi, T. Giannehs, E.P. Manias, E. Lomakin, S. Lichtenham, J.D. Jones, P. Flammabihty studies of pol3mer layered silicate nanocomposites polyolefin, epoxy, and vinylester resins. In M. Le Bras, G. Camino, S. Bourbigot, and R. Delobel, Eds., Fire Retardancy of Polymers The Use of Intumescence. Royal Society of Chemistry, London, 1998, pp. 203-221. 

Becker O, Varley R and Simon G (2002) Morphology, thermal relaxations and mechanical properties of layered silicate nanocomposites based upon high-functionality epoxy resins, Polymer 43 4365-4373. 

A study by Shah et on die moisture diffusion of a (non-epoxy) vinyl ester resin-based layered silicate nanocomposite also reported a deereased moisture diffiisivity of the nanocomposite, ascribed to the restricted mobility of the polymer chains tethered to the clay particles. A reverse effect, however, could be observed for the equilibrium water uptake of one of the two fillers investigated. The equilibrium water uptake of a vinyl-monomer containing clay nanocomposites increased from 0.012% (neat resin) to 0.021 (5% clay). The water uptake of the other, an alkyl ammonium-treated montmorillonite clay, Cloisite lOA, remained relatively unaffected by the filler addition. The increase of the first nanocomposites system was related to the strong, hydrophilic behaviour of the clay, which remains to some degree in the surface treated state. 

B. Schartel, U. Knoll, A. Hartwig, and D. Ptttz, Phosphonium-modified layered silicate epoxy resins nanocomposites and their combinations with ATH and organo-phosphorus fire retardants, Polym. Adv. Technol., 2006, 17 281-293. 

Fig. 18 Glass transition temperature, Tg, of highly crosslinked epoxy nanocomposite systems. The resin systems are diethyltoluene diamine cured octadecylammonium modified layered silicate DGEBA, TGAP and TGDDM [63]...

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