Inorganic nano filler

It has been shown that at semi crystalline polymers with devitiificated amorphous phase consideration as natural hybrid nanocomposites their anomalous high reinforcement degree is realized at the expense of crystallites partial recrystallization (mechanical disordering), that means crystalline phase participation in these polymers elastic properties formation. It is obvious, that the proposed mechanism is irrapplicable for the description of polymer nano composites with inorganic nano fillers. 

Thus, the performed estimations demonstrated, that high values of reinforcement degree EIE for semi crystalline polymers, considered as hybrid nano composites (in case of studied HDPE EIE value is varied within the limits of 10-110) were due to recrystallization process (mechanical disordering of crystallites) inelastic deformation process and, as consequence, to contribution of crystalline regions in polymers elastic properties formation. It is obvious, that this mechanism does not work in case of inorganic nano filler (e.g., organoclay). Besides, a nano filler... 

MarciniSin, A., Hricova, M., Ujhelyiova, A., et al. Effect of inorganic (nano)fillers on the UV barrier properties, photo and thermal degradation of polypropylene fibres. Fibres Text East Eur. 17, 29-35 (2009)... 

Another approach extensively apphed in recerrt years to improve the ion conductivity ((, lithiirm ion transference number (C), mechanical properties, and the electrode-electrolyte interfacial stability of a polymer electrolyte is the addition of inorganic or ceramic fillers into the polymer-salt complexes (Capiglia et al., 1999 Kim et al., 2003 Chen-Yang et al., 2008 Croce et al., 2001 Rahman et al., 2009 Shen et al., 2009 Zhang et al., 2011 Munichandratah et al., 1995 Wiec-zorek, 1992). Micro and nano-sized inorganic filler such as silicone oxide (SiO ), alumina (AI2O3), ceria (CeO ), and so on are incorporated into PEO-salt complex in an effort to improve the mechanical, thermal stabihty, and ion conductivity of PEO-based polymer electrolytes. The effect of nano-fillers on the thermal properties of the PEO-based polymer complex varies with the type of nano-particles as well as the polymer-salt complex host matrix. 

For PEEK matrix nanocomposites,a small amount of inorganic nanoparticles, such as SijN4, Si02, SiC, and Zr02, contributed to a reduction in the frictional coefficient from about 0.4 for the neat matrix down to about 0.2 at high nano-filler contents. The dominant wear mechanisms were modified from adhesive and fatigue wear in the case of neat PEEK to a mild abrasive wear of the nanocomposites. However, with a further increase in nano-filler content, particle agglomeration occurred and resulted in a severe abrasive wear, as observed on the worn surfaces. ... 

With respect to the influence of filler content, it can be eoncluded that there is often an optimum filler loading corresponding to the lowest wear rate of the nanocomposites. Such a U-shaped dependence of wear rate on nano-filler concentration has been found in many reports, like the systematic investigations on PEEK composites filled with a series of inorganic nanoparticles. " " Nevertheless, the filler content dependence of frictional coefficient usually does not follow this rule. The frictional coefficient often decreases (or increases) slightly with increasing filler content and at times even varies irregularly with filler content. 

This is stimulated by selective interaction of described inorganic fillers with aggressive media. Hydrate complexes formed fill macropores and microcracks of coatings. This process results in repair of defects and the material is hardened and becomes less penetrable [6,7], The free volume of nano-heterogenic coatings simultaneously decreases. 

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