As an important signal in response to mechanical force, phosphorescence has the advantages of long luminescence lifetime, large Stokes shift, and involvement of triplet states [
5]. Recently, Yong Chen, Yu Liu and co-workers from Nankai University synthesized a pseudopolyrotaxane (NPR) utilizing
α-CD and naphthalene-derived polyethylene glycol (NPEG) (
Fig. 1) [
6]. The PEG chains, anchored at both ends of the naphthalene moiety, are threaded through the
α-CD cavities, thereby forming the NPR. By combining NPR with waterborne polyurethane (WPU), they prepared supramolecular elastomers exhibiting reversible mechanically responsive room temperature phosphorescence (RTP) enhancement during the mechanical stretching process. The incorporation of CDs containing abundant hydroxyl groups not only facilitates the attainment of prolonged phosphorescence emission
via the macrocyclic confinement effect but also augments mechanical properties through the establishment of hydrogen bonds with WPU chains. The resultant elastomer exhibits robust RTP characteristics, maintaining emission stability in aqueous solutions and diverse chemical environments. Notably, under a 200% strain, the phosphorescence intensity increases threefold owing to the further suppression of non-radiative transitions and NPR vibrations. Lastly, the developed RTP elastomer finds applications in information security and encryption.