Improving the tribological properties of polymer nanocomposites

The reinforcement material composition affects the composition and properties of the transfer layer that forms during sliding which controls friction and wear behaviour in most nanocomposite systems. A uniform, tenacious transfer film is produced in clay-nylon-6 nanocomposites, which leads to a reduction in friction and a lower wear rate (Srinath and Gnanamoorthy, 2005). Similar results are observed for silica nanoparticle reinforcement (Garcia et al, 2004). 

1 Effect of reinforcement diameter on wear performance for silica-polyurethane nanocomposites (12 vol%). 

Improvements in friction and wear have also been reported with carbon nanotube reinforced polymer composites (Igarashi et al., 2005). This is due to both increases in strength of the material and the modification of the transfer layer by fragments of nanotube which can reduce friction. There is an optimum nanotube composition (Cai et al., 2004) typically about 10% by weight, for the best wear performance (Werner et al., 2004). 

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