Shape memory polymer nanocomposite with multi-stimuli response and two-way reversible shape memory behavior

In this work, a novel type of shape memory polymer nanocomposite was fabricated using chemically cross-linked poly(ε-caprolactone) with allyl alcohol as the matrix and Fe3O4 nanoparticles decorated conductive multiwalled carbon nanotubes (Fe3O4@M) as a magnetism and electricity responsive source. The nanocomposite exhibited excellent shape memory performance with a multistage stimulus recovery from a temporary shape to a permanent shape, triggered by an alternating magnetic field, an electric field and hot water, respectively. Uniquely, the nanocomposite also displayed significant two-way reversible shape memory behavior under constant load conditions, which was not demonstrated previously. An alamar blue assay was also used to prove that the material possessed good biocompatibility. The results showed that the material could have good potential application in sensors, functional tissue engineering constructs and artificial muscles.