PERCOLACIÓN, UNIVERSALIDAD Y PROPIEDADES ELÉCTRICAS DE NANOCOMPUESTOS POLÍMEROS/NANOTUBOS DE CARBÓN, PCL/PLA/NTC

Abstract

The reinforcement of the blend poly(e-caprolactone)/polilactide, PCL/PLA, 70/30, with  multiwall carbon  nanotubes, leads to the improvement of the mechanical, dielectric and  electrical properties of these nanocomposites; the CNT weight concentrations studied, p, ranged from 0 to 4% and the frequencies varied from 10-3 to 107 Hz and temperatures from 143 up to 313 K. The sea-island morphology of the immiscible blend was observed together with the selective location of the CNT. The nanofiller was dispersed in the PCL phase, some of the CNT were selectively  being located at the PLA interphase. The DC conductivity as a function of p varied 10 orders of magnitude at room temperature, thus evidencing the existence of a percolation mechanism for the charge carriers in the insulating matrix at a critical CNT concentration of 0.98%. The critical exponents, the tunneling among CNT not yet in physical contact, the behavior with temperature and the universality of the electrical behavior of the nanocomposites were also studied.