Nanocarbonaceous materials with specific geometries and physicochemical properties allow the development of highperformance polymer-based smart composite materials. Among them, chemical treatments of graphene allow tailoring its electrical conductivity and, therefore, tuning functional response of materials for sensing applications. Polymer-based nanocomposites have been developed from styrene−ethylene−butylene−styrene (SEBS), a high deformation thermoplastic elastomer, and different graphene-based fillers, including graphene oxide (GO), reduced graphene oxide (rGO), and graphene nanoplatelets (G-NPLs). It is shown that the electrical conductivity shows a percolation threshold around 2 wt % for GO and rGO, remaining nearly independent of the filler content for G-NPL filler contents up to 6 wt %. Furthermore, GO/SEBS and rGO/SEBS composites show high piezoresistive sensibility with gauge factors ranging from 15 up to 120 for strains up to 10%. Thus, GO/SEBS and rGO/SEBS composites can represent a new generation of materials for strain sensor applications, as demonstrated in their implementation in a hand glove prototype with finger movement monitoring.

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Flexible polymer-based magnetoelectric (ME) materials are developed based on novel CoFe 2 O 4 (CoFO) nanoellipsoids and poly-[vinylidenefluoride-co-trifluoroethylene] [P(VDF -TrFE)]. The synthesized noncytotoxic CoFO nanoellipsoids (270 nm × 50 nm) show high magnetization, ≈170 emu•g −1 , high magnetostriction, ≈300 ppm, and magnetic anisotropy that, coupled to the piezoelectric response of P(VDF-TrFE), |d 33 | = 21 ± 1 pC•N −1 , lead to an interfacial ME coupling (α) of 1.50 mV•cm −1 •Oe −1 . Further, nanoellipsoid orientation within the polymer matrix allows an anisotropic ME response of the CoFO/P(VDF-TrFE) composite. Such a response is dependent on the angle between the dc magnetic field direction and the nanoellipsoids length direction. The proposed mechanism for the anisotropic behavior allows the tailoring of the ME response to contactless sensing applications.