Isocyanate Modified GO Shape-Memory Polyurethane Composite.

Shape-memory composites have benefits for minimally invasive surgery, but their wider applications for bone repair are hindered by conflicts between the mechanical and memory performances, especially at load-bearing locations. In this study, we fabricated a graphene oxide shape-memory polyurethane composite through the chemical combination of graphene oxide and isocyanate, in order to realize satisfactory mechanical and shape-memory effects. As desired, a modulus of ~339 MPa and a shape recovery ratio of 98% were achieved, respectively, in the composite. In addition, finite element analysis demonstrated that, after being implanted in a defective bone through a minimally invasive treatment, where the highest stress was distributed at the implant-bone interface, this composite could offer a generated force during the recovery process. Furthermore, we also discuss the origins of the improved mechanical and memory properties of the composites, which arise from increased net-points and the stable molecular structure inside. Therefore, with its superior structure and properties, we envision that this shape-memory composite can provide new insights toward the practical application of shape-memory polymers and composites in the field of bone repair.