The design of nanometric electronic devices requires novel materials for improving their electrical performance from stages of design until their fabrication. Until now, several DC electrical conductivity models for composite materials have been proposed. However, these models must be valued to identify main design parameters that more efficiently control the electrical properties of the materials to be developed. In this paper, four different models used for modeling DC electrical conductivity of carbon nanotube-polymer composites are studied with the aim of obtaining a complete list of design parameters that allow guarantying to the designer an increase in electrical properties of the composite by means of carbon nanotubes.

The objective of the present work was to evaluate the effect of the incorporation of plasticizing agents; Glycerin and PVA, as well as the incorporation of aloe extract on the regeneration and / or cellular recovery capacity of plasticized chitosan. The preparation of the biofilms consisted of mixing, low molecular weight chitosan (0.5, 1 and 1.25%), polyvinyl alcohol (1 and 1.5%) and glycerin (3.5, 5 and 7%). Aloe extract was incorporated in 1% together with glycerin. The drying of the films was carried out in an incubator at 28 ° C for 24 hours, using the method of slow evaporation or casting. Stress tests to determine their mechanical properties, DSC compatibility, water vapor permeability tests and through a cytotoxic activity test of biofilms using human gingival fibroblasts (HGF), the viability of the use of these biofilms in regeneration was determined mobile. A combination of chitosan / PVA / glycerin was found that exhibits good elastic properties. The DSC showed that there is a good incorporation of the components. The permeability is acceptable for the application and the cell viability tests indicate an increase thereof due to the presence of the aloe extract, as well as the plasticizers with respect to the chitosan without plasticizers.