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تسجيل مستخدم جديدTwo-step electrical percolation in nematic liquid crystal filled by multiwalled carbon nanotubes
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Percolation of carbon nanotubes (CNTs) in liquid crystals (LCs) opens way for a unique class of anisotropic hybrid materials with a complex dielectric constant widely controlled by CNT concentration. Percolation in such systems is commonly described as a one-step process starting at a very low loading of CNTs. In the present study the two-step percolation was observed in the samples of thickness 250 $mu$m obtained by pressing the suspension between two substrates. The percolation concentrations for the first and second percolation processes were $C_n^{p_1}approx 0.0002$ wt. % and $C_n^{p_2}approx 0.5$ wt. %, respectively. The two-stage nature of percolation was explained on a base of mean field theory assuming core-shell structure of CNTs.
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