Shape memory polymers (SMPs) are a class of stimuli responsive materials

which may recover their original shapes from large deformation upon the application of an external stimulus such as heat

electricity

alternating magnetic fields

light

water or chemicals

et al. They have been widely used in the fields of biomedical materials

aerospace

automobiles

textiles as smart materials. However

their development and applications are partly restricted by their low mechanical properties

such as low strength

elastic modulus

recovery forces and slow recovery rates. Incorporation of nanoparticles would contribute to the improvement of mechanical and shape memory properties of SMPs. Based on a fundamental understanding of the shape memory mechanism of SMPs

this paper aims to provide a review of shape memory polymer nanocomposites

including the purpose of the incorporation of nanoparticles

stimulus methods and mechanism

the interaction mechanism between nanoparticles and polymer matrix and their potential applications. Finally

the research trends of SMP nanocomposites are also summarized.