Stimuli-Responsive Reversible Two-Level Adhesion from a Structurally Dynamic Shape-Memory Polymer.
A shape-memory adhesive has been prepared that exhibits two levels of reversible adhesion. The adhesive is a semicrystalline cross-linked polymer that contains dynamic disulfide bonds. Melting of the crystalline regions via heat causes a drop in the modulus of the material facilitating wetting of the substrate as well as enhancing the surface contact area with the substrate, which result in the formation of an adhesive bond. Exposure to higher heat or UV light results in dynamic exchange of the disulfide bonds, which yields a further drop in the modulus/viscosity that improves surface wetting/contact and strengthens the adhesive bond. This improvement in adhesion is shown to apply over different substrates, contact forces, and deformation modes. Furthermore, the adhesive acts as a thermal shape-memory material and can be used to create joints that can reposition themselves upon application of heat.
Department of Macromolecular Science and Engineering, Case Western Reserve University , 2100 Adelbert Road, Cleveland, Ohio 44106-7202, United States.
Brian T
BT
Michal
Department of Macromolecular Science and Engineering, Case Western Reserve University , 2100 Adelbert Road, Cleveland, Ohio 44106-7202, United States.|Hathaway Brown School , 19600 North Park Blvd., Shaker Heights, Ohio 44122, United States.
Emily J
EJ
Spencer
Department of Macromolecular Science and Engineering, Case Western Reserve University , 2100 Adelbert Road, Cleveland, Ohio 44106-7202, United States.
Stuart J
SJ
Rowan
adhesive; disulfides; dynamic network; reversible; shape memory