A. Sanchez-Solis*, Ricardo Perez**, Aurora Ponce, Fausto Calderas and Octavio Manero. Instituto de Investigaciones en Materiales, UNAM. Apartado Postal 70-360, Delegación Coyoacán 04510 DF, México.* sancheza@unam.mx, ** pechari19@gmail.com The effect of the application of double extrusion, first with twin screw extrusion and subsequently with single screw extrusion-ultrasound on blends of polypropylene, carbon nanotubes, clay and nanographite was studied. Clay was chemically modified with amino acid L-lysine salt. Nanographite was obtained through a sonication process with a solution of HASE (Hyper Alkali Swellable Emulsion) at different frequencies and amplitudes. The results suggest that dispersion and distribution of the nanoparticles are favoured with the application of extrusion-ultrasound improving tensile mechanical, dielectric constant and Izod impact notched properties. The best results were obtained with solutions of graphite-HASE 95/5 % weight and 15 days of ultrasound exposure. The dielectric constant of these compounds pass from 2.4 to 9.5 making them susceptible to be used as electromagnetic interference shielding and electrostatic discharge materials because its higher electrical conductivity. Report analyses determinations of X-ray, scanning electronic microscopy, thermal analysis and rheology as well. Keywords: nanographite, clay, nanocomposites, extrusion-ultrasound.