Multi-stimuli sensitive shape memory poly(vinyl alcohol)-graft-polyurethane

A multi-stimuli sensitive shape memory poly(vinyl alcohol)-graft-polyurethane was synthesized. Fourier transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (1H-NMR) confirmed the chemical structure of the material. The material exhibits good water-induced shape memory behavior and a thermally induced dual shape memory effect. Further study indicated that the material exhibits good triple shape memory behavior. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) demonstrated that the polymer possesses a wide transition temperature, which resulted in excellent dual- and triple-shape memory effects. DSC and swelling experiments were carried out to find that the mechanism of the water-induced shape memory effect involves the decrease of the transition temperature when it swelled in water. Alamar Blue assay showed that the material possesses good biocompatibility and can be potentially used in the field of biomaterials.