Researchers from NanoUp group, in collaboration with researchers from University of Malaga, just published an article in Angew. Chem. Int. Ed. In this work we demonstrate that swelling behaviour of flexible MOF crystals can be used to create a self‐folding polymer films that undergoes reversible shape transformations upon exposure to polar solvents and vapours, exhibiting shape-memory effect.
One of the most fascinating properties of some MOFs is their ability to undergo expansion or contraction due to adsorption or desorption, respectively. This well-known swelling behaviour of flexible MOFs can be exploited to create a self-folding polymer film by integrating MOF crystals into a polymer matrix.The resulting composite film selectively bends to certain solvents and its degree of folding can be controlled by controlling the relative humidity. Moreover, it shows a shape-memory effect at relative humidity values from 60% to 90%. Finally, these composite films can lift cargo and can be used to assemble 3D structures from 2D patterns.
Read the article here