Thermal properties nanocomposites

Hoidy, W.H., Al-Mulla, E.A.J., and Al-Janabi, K.W. 2010c. Mechanical and thermal properties of PLLA/PCL modified clay nanocomposites. Journal of Polymers and the Environment. 18, 608-616. 

Meneghetti, P. and Qutubuddin, S. 2006. Synthesis, thermal properties and applications of polymer-clay nanocomposites. Thermochimica Acta 442 74-77. 

TABLE 1 Mechanical and Thermal Properties of Nylon-6 and Nylon-6-Clay Nanocomposites... 

CNTs can enhance the thermal properties of CNT-polymer nanocomposites. The reinforcing function is closely associated with the amount and alignment of CNTs in the composites. Well-dispersed and long-term stable carbon nanotubes/ polymer composites own higher modulus and better thermal property as well as better electronic conductivity (Valter et al., 2002 Biercuk et al., 2002). Both SWNT and MWNT can improve the thermal stability and thermal conductivity of polymer, the polymer-CNT composites can be used for fabricating resistant-heat materials. 

Polymer-clay nanocomposites (PCN) are a class of hybrid materials composed of organic polymer matrices and organophilic clay fillers, introduced in late 1980s by the researchers of Toyota (Kawasumi, 2004). They observed an increase in mechanical and thermal properties of nylons with the addition of a small amount of nano-sized clays. This new and emerging class of pol miers has found several applications in the food and non-food sectors, such as in constmction, automobiles, aerospace, military, electronics, food packaging and coatings, because of its superior mechanical strength, heat and flame resistance and improved barrier properties (Ray et al., 2006). 

Because of the unique combination of mechanical, electrical, and thermal properties, the CNTs have been excellent candidates to substitute or complement the conventional nanofillers in the fabrication of multifunctional PNs. The first PNs using CNTs as the nanoadditive was reported in 1994.20 By far, the CNTs have been the second most investigated nanoadditives to reduce the flammability of the polymers through nanocomposite technology. A difficulty of the application of the CNTs in polymers is the dispersion of CNTs in the matrix polymer, and the high cost of the CNTs is another problem. 

Leszczynska, A., Njuguna, J., Pielichowski, K., and Banerjee, J. R. (a) Polymer/montmorillonite nanocomposites with improved thermal properties, Part I Factors influencing thermal stability and mechanisms of thermal stability improvement, Thermochim. Acta (2007), 453, 75-96. (b) Polymer/montmorillonite nanocomposites with improved thermal properties. Part II Thermal stability of montmorillonite nanocomposites based on different polymeric matrixes, Thermochim. Acta (2007), 454, 1-22. 

The methodology [21] that has been used to the PA6 nanocomposite to deduce the thermal properties and critical heat flux was applied to the EVA and PBT nanocomposites (Section 19.7.1.1). The corrected ignition times as a function of the external heat flux for both EVA and PBT nanocomposites are shown in Figure 19.33. The final deduced thermal properties and critical heat flux are summarized in Table 19.7, along with the values reported for pure EVA and PBT in [22],... 

Effective Thermal Properties of PA6, EVA, and PBT Nanocomposites Derived in This Work, Together with Those Reported for Pure Polymers... 

Gong, F., Feng, M., Zhao, C., Zhang, S., and Yang, M. 2004. Thermal properties of poly(vinyl chloride)/ montmorillonite nanocomposites. Polym. Deg. Stab., 84(2) 289-294. 

The results are reported of an in depth study of the structure, thermal properties, dynamic mechanical properties, flammability and smoke properties of melt blended PVC-sodium montmorillonite nanocomposites. Investigative properties employed included X-ray diffraction, TEM, TGA, DMA and cone calorimetry. The effects of clay loading, DOP concentration, annealing, blending time and molec.wt. on the formation of the composites are discussed and fire properties of PVC-organically modified clay and PVC-sodium clay nanocomposites are presented and discussed. 15 refs. USA... 

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