Dual responses of magnetite-graphene hybrid in polyurethane under magnetic and electric stimuli

Dual responsive material composed of magnetite nanoparticle (MNP) and graphene nanosheet (GP) as a hybrid filler and polyurethane (PU) as an electrostrictive matrix was fabricated. The hybrid filler was synthesized by the in-situ growth of MNP on the GP surface. The obtained hybrid particles behaved simultaneously as a superparamagnetic and conducting material. The hybrid-composites possessed electronic polarization and high response towards electric field, as they showed excellent recoverability and fast response during the temporal test under electric field. The highest storage modulus sensitivity was obtained from the 0.5%v/v MNP-GP/PU at the value of 3.97 under the applied electric field of 2 kV/mm. In the deflection experiment, the 0.5%v/v MNP-GP/PU composite exhibited the largest bending distance of 13.65 mm under the electric field of 500 V/mm. On the other hand, the 3.0%v/v MNP-GP/PU yielded the maximum bending of 15.35 mm under the magnetic field of 1650 G.