Clays nanoclay-reinforced nanocomposites

Dai G, Mishnaevsky Jr L (2013) Damage evolution in nanoclay-reinforced polymers a three-dimensional computational smdy. Compos Sci Technol 74 67—77 Durmus A, Woo M, Kas goz A, Macosko CW, Tsapatsis M (2007) htbnealated linear low density polyethylene (LLDPE)/clay nanocomposites prepared with oxidized polyethylene as a new type compatibilizer stmctural, mcehanieal and barrier properties. Eur Polym J 43 3737—3749 Pan J, Liu S, Chen G, Qi Z (2002) SEM study of polystyrene/clay nanocomposite. J Appl Polym Sci 83 66-69... 

Joshi et al. reported that nanoclay reinforced PP nanocomposites could be spun and drawn successfully for 0.5,1.0 and 1.5 wt% of the modified clay loading. Beyond 1.5 wt% the spirmability is poor." The modified clay content in the range of 0.5-1.0 wt% gives optimum properties." ... 

This chapter reviews the use of the sepiolite/palygorskite group of clays as a nanofiller for polymer nanocomposites. Sepiolite and palygorskite are characterized by a needle-like or fiber-like shape. This peculiar shape offers unique advantages in terms of mechanical reinforcement while, at the same time, it allows to study the effect of the nanofiller s shape on the final composite properties. The importance of the nanofiller shape for the composite properties is analyzed in Section 12.2, introducing the rationale of the whole chapter. After a general description of needle-like nanoclays in Section 12.3, the chapter develops into a main part (Section 12.4), reviewing the preparation methods and physical properties of polyolefin/needle-like clay nanocomposites. 

The addition of nanoparticles to synthetic rubber resulting in enhancement in thermal, stiffness and resistance to fracture is one of the most important phenomena in material science technology. The commonly used white filler in mbber industry are clay and silica. The polymer/clay nanocomposites offer enhanced thermo mechanical properties. Bourbigot et al. observed that the thermal stability of polystyrene (PS) is significandy increased in presence of nanoclay [75]. Thermal and mechanical properties of clays multiwalled carbon nanotubes reinforced ethylene vinyl acetate (EVA) prepared through melt blending showed synergistic effect in properties [76]. 

Some of the most widely studied and technologically relevant polymer nanocomposites used in PLA technologies are those making use of nanoclays as reinforcing fillers. In order to achieve a full understanding of the nanocomposite behaviour and, therefore, of the system behaviour and performance, it is necessary to understand the structure and characteristics of nanoclays. With this objective, a small section of this chapter is devoted to analyzing the basic concepts of the nanoclays, with special interest in the most interesting/widely used clays for these applications. 

Noble Polymers supplies a 6% nanoclay-PP composite for the structural seat back of the Honda Accura TL 2004 car. It replaces a 30% glass PP compound in the seat back. Noble Polymers is also targeting the replacement of 20% glass fibre reinforced PP in office furniture parts. Southern Clay Products supplies Cloisite nanocomposite external parts to General Motors for its Impala vehicle, in competition with talc-filled PP. 

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