Scientists in China have designed a velcro-like material held together by non-covalent interactions that can be unfastened by electrical means and refastened again under pressure.
The velcro is ‘stuck’ together by compressing a flexible, conductive poly(ionic liquid) membrane (PIL) functionalised with ferrocene (Fc) with a PIL functionalised with β-cyclodextrin (β-CD). The strong binding of the Fc groups within the β-CD cavities causes the layers to adhere together tightly. Oxidation of the Fc moieties to ferrocenium ions (Fc+) by chemical or electrochemical means causes the layers to come unstuck, as the charged Fc+ is not bound inside the hydrophobic β-CD cavity. A reducing potential and further pressing reassembles the material.
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A hook-and-loop strategy fastens the layers together but these links can be unfastened by an electric current
Read the full article in Chemistry World»
Read the original journal article in Chemical Science – it’s free to download until 19th June:
Flexible and Voltage-Switchable Polymer Velcro Constructed by Host−Guest Recognition Between Poly(ionic liquid) Strips
Jiangna Guo, Chao Yuan, Mingyu Guo, Lei Wang and Feng Yan
Chem. Sci., 2014, Accepted Manuscript
DOI: 10.1039/C4SC00864B, Edge Article