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Partially bio‐based conducting polymer nanocomposites constituted by poly(lactic acid) (PLA)/ethylene‐co‐vinyl acetate (EVA) (50:50 wt%) blend loaded with different amounts of carbon nanotube (CNT) were prepared for developing microwave absorbing materials. The effect of EVA characteristics and the mixing conditions on the electrical conductivity was investigated. The higher conductivity value was achieved using PLA@CNT master batch and EVA with 28% of VA. In fact, this system presented electrical percolation threshold of 7 × 10−4 volume fraction and a conductivity value of 3 × 10−3 S/m with the addition of 0.9 wt% (0.58 vol%) of CNT. A minimum reflection loss of −29 dB (electromagnetic (EM) attenuation of around 99.9%) at 11.7 GHz and the bandwidth (<−10 dB) of 4.9 GHz was observed with the presence of 0.58 vol% of CNT, whereas RL value of around −39.4 dB (EM attenuation of around 99.99%) at 14.7 GHz and a bandwidth of 4.6 GHz was observed for the composite loaded with 0.25 vol% of CNT. Due to the outstanding microwave absorption properties and wide absorption bandwidth with low amount of CNT, these composites are promising candidates for flexible materials suitable for shielding electronic devices in a wide frequency range. [ABSTRACT FROM AUTHOR]

Conducting polymer composites constituted by co‐continuous poly (vinylidene fluoride) (PVDF)/ ethylene‐ vinyl acetate copolymer (EVA) blends with multiwalled carbon nanotube (CNT) were prepared by melt mixing using different procedures. The effect of the master batch approach on the conductivity, morphology, mechanical, thermal and rheological properties of PVDF/EVA/CNT nanocomposites was compared with that based on one step mixing strategy. The selective extraction experiments revealed that CNT was preferentially localized in the EVA phase in all situations, even when PVDF@CNT master batch was employed. Nanocomposites prepared with EVA@CNT master batch displayed higher conductivity, whose value reached around 10−1 S m−1 with the addition of 0.56 vol% of CNT. The better electrical performance was attributed to the better distribution of the filler, as indicated by transmission electron microscopy and rheological behavior. The electrical and rheological behavior were also investigated as a function of the CNT content. [ABSTRACT FROM AUTHOR]