Micheletti, Cosimo Soldati, Luca Weder, Christoph Pucci, Andrea Clough, Jess M. 2024 The optical detection of mechanical strain and stress in polymers is a powerful and convenient approach for studying deformation processes in these materials and identifying damage prior to failure in crucial components. We show here that mechanochromic behavior can be introduced via a straightforward one-step process that involves the modification of a commercial polyolefin elastomer (POE) grafted with reactive anhydride groups with small amounts (<0.8 wt%) of mechanochromic cross-linkers (Loop or sPDI). These motifs contain excimer-forming perylene diimides (PDIs) and react with POE to afford mechanochromic polyolefin elastomers (POE-Loop or POE-sPDI). The Loop motif contains two excimer-forming PDI moieties that can form folded structures in which the two PDIs within the Loop motif interact with each other, i.e. intra-Loop, while sPDI contains one PDI that can only form interactions with PDIs of other sPDI probes. Upon mechanical deformation of POE-Loop and POE-sPDI, the dye aggregates disassemble, and the ratio of monomer-to-excimer emission intensity increases. The data suggest that dye interactions between probes, i.e. inter-Loop or inter-sPDI, dominate the optical characteristics of both polymers. application/pdf https://folia.unifr.ch/global/documents/328611 https://folia.unifr.ch/documents/328611/files/240509_poe-loop_0.pdf https://folia.unifr.ch/documents/328611/files/240509_poe-loop_si_0.pdf eng https://pubs.acs.org/doi/10.1021/acsapm.4c00842 info:eu-repo/semantics/altIdentifier/issn/2637-6105 info:eu-repo/semantics/altIdentifier/doi/10.1021/acsapm.4c00842 info:eu-repo/semantics/openAccess Rights reserved ACS Applied Polymer Materials. - American Chemical Society. - 2024, vol. 6, no. 6572-6580 mechanochromism mechanochemistry supramolecular polymers sensing info:eu-repo/classification/udc/54 Mechanochromic Polyolefin Elastomers http://purl.org/coar/resource_type/c_816b