The demand for multifunctional requirements in aerospace, military, automobile, sports, and energy applications has encouraged the investigation of new composite materials. This study focuses on the development of multiwall carbon nanotube (MWCNT) filled polypropylene composites and carbon nanofiber composite mats. The developed systems were then used to prepare interlayered composites that exhibited improved electrical conductivity and electromagnetic interference (EMI) shielding efficiency. MWCNT-carbon nanofiber composite mats were developed by centrifugally spinning mixtures of MWCNT suspended in aqueous poly(vinyl alcohol) solutions. The developed nanofibers were then dehydrated under sulfuric acid vapors and then heat treated. Interlayered samples were fabricated using a nanoreinforced polypropylene composite as a matrix and then filled with carbon fiber composite mats. The in-plane and through-plane electrical conductivity of an eight-layered flexible carbon composite (0.65 mm thick) were shown to be 6.1 and 3.0 × 10−2 S·cm−1, respectively. The EMI shielding effectiveness at 900 MHz increased from 17 dB for the one-layered composite to 52 dB for the eight-layered composite. It was found that the reflection of the electromagnetic waves was the dominating mechanism for EMI shielding in the developed materials. This study opens up new opportunities for the fabrication of novel lightweight materials that are to be used in communication systems.

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Se caracteriza la influencia de las corrientes filosóficas y científicas en el quehacer de la pensamiento pedagógico cubano, su surgimiento y desarrollo desde fines del siglo XVII, XIX y principio de XX, entre quienes se destacan: José A. Caballero (1762–1835), Félix Varela (1788-1853), José de la Luz y Caballero (1800-1862), José Martí (1853-1895) y Enrique José Varona (1849-1933), gloriosas figuras del pensamiento filosófico pedagógico  cubano, los cuales supieron cimentar ideas sólidas y modernas en lo referente a la concepción filosófico-política de la nacionalidad cubana y con ello reafirmar la identidad pedagógica cubana. PALABRAS    CLAVE:    Pensamiento    pedagógico    cubano;    corrientes    filosóficas; nacionalidad cubana. ABSTRACT This article characterizes the influence of the scientific and philosophical trends in the Cuban pedagogical thinking, its origin and development from the end of the XVII, XIX centuries and the beginning of the XX century. Among the most outstanding figures of the school of Cuban thought, we should mention: José A. Caballero (1762-1835), Félix Varela (1788-1853), José de la Luz y Caballero (1800-1862), José Martí (1853-1895), and  Enrique  José  Varona  (1849-1933).  They  knew  how  to  consolidate  solid  and modern ideas regarding the political-philosophical conception of the Cuban nationality, and as a result, they reaffirmed the Cuban pedagogical identity. KEYWORDS: Cuban pedagogical thinking; philosophical trends; Cuban nationality.