The effect of annealing temperature and time on the dielectric and piezoelectric response of poly(vinylidene fluoride), PVDF, has been studied. The observed decrease in the value of the dielectric, ´, and piezoelectric, d 33 , constants is related to depoling of the material and not to variations of the degree of crystallinity or the electroactive -phase content. In a general way, the dielectric and piezoelectric responses decrease strongly in the first four hours at a given temperature, in particular for temperatures higher that 80 ºC, reaching stable values for longer annealing times. For most applications, the temperature of 100 ºC will set the limit of suitable performance. Nevertheless, the material still retains stable piezoelectric response of ~ 4 pC/N after reaching temperatures of

The piezoresistive effect on poly(propylene) (PP)-carbon nanofibre (CNF) composites fabricated by twin-screw extrusion and compression moulding has been investigated. The electrical and mechanical properties of PP/CNF composites have been obtained as a function of CNF concentration. Electrical conductivity exhibited low thresholds and values close to the required levels for EMI shielding applications at 2.4 vol%. Meanwhile the elastic modulus showed an enhancement with a maximum up to 130% for one of the composites at 0.9 vol% loading. Further, the piezoresistive response has been evaluated in four-point bending. Positive gauge factors between 2 and 2.5 have been obtained. The highest gauge factors are found within the percolation threshold. The characteristics of the materials and the production technique make them suitable for large scale applications.

A cost-competitive, flexible and safe thermoelectric polyamide 6,6 (PA66) fabric coated with glycerol-doped PEDOT:PSS (PEDOT:PSS + GLY) for use in large area textiles as a heating element in several applications.

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In this work, epoxy composites reinforced with vapor‐grown carbon nanofibers were prepared by a simple dispersion method and studied in order to identify the main conduction mechanism. The samples show high electrical conductivity values. The results indicate that a good cluster distribution seems to be more important than the fillers dispersion in order to achieve high conductivity values. Interparticle tunneling has been identified as the main mechanism responsible for the observed behavior.