Slide‐Ring Supramolecular Mechanoresponsive Elastomer with Reversible Luminescence Behavior

Abstract A solid slide‐ring supramolecular elastomer is constructed by free‐radical polymerization of 2‐(2‐methoxyethoxy)ethyl methacrylate, acrylate‐modified perylene diimides (PDI), and the polyrotaxane (PR) cross‐linker. Benefiting from reciprocating shuttle function of slide‐ring PR formed by acrylate‐modified α‐cyclodextrin threading on polyethylene glycol, the resultant supramolecular elastomer not only presents excellent tensile property, toughness, and fatigue resistance up to 100 cycles, but also gives reversible mechano‐induced fluorescence changes from red to orange luminescence due to a reversible conversion of PDI dimer to monomer upon mechanical stretching. After the dye molecule Nile blue is added as a fluorescent acceptor, the supramolecular elastomer exhibits highly reversible mechano‐induced regulation of energy transfer and can perform five cycles without optical fatigue. This bifunctional mechanochromic slide‐ring supramolecular elastomer, which not only possesses mechanically reversible motion of the slide‐ring cross‐linkers but also has the mechanochromic response of fluorophore, endows the intrinsic superiority of slide‐ring into fatigue resistant mechanoresponsive strain sensing materials.