Nanocompuestos conductores basados en nanotubos de carbono y poliamidasestudio de sus propiedades eléctricas, reológicas y su morfología

Abstract

The main target of this Doctoral thesis was the design and characterization of new conductive polymer composites using blends of different polyamides, as matrix, and multiple wall carbon nanotubes, as conducting nanofillers. In order to analyse the influence of polyamide miscibility on the electrical properties of nanocomposites, two different blends were selected: a partially miscible polyamide blend and an immiscible polyamide blend. During the development of this work, particular emphasis has been placed on assessing the relationships between processing, morphology and macroscopic properties of the different nanocomposites. The ultimate purpose was to maximize the properties achieved with the minimum amount of carbon nanotubes. As the dispersion state of carbon nanotubes directly influences the properties of the conductive network and, therefore, the final macroscopic properties, this aspect was studied from a qualitative and quantitative point of view. The effects of the type of polyamide, polyamide ratio, degree of miscibility between polyamides selected as matrix and type of predispersion, used to prepare the conductive polymer composites, were evaluated. Using an immiscible polyamide blend, a segregated conductive network was obtained. This structure allowed the optimization of the nanocomposites electrical properties.