Probing bond scission process in a broader force range was realized by embedding mechanochromic rhodamine and mechanochemiluminescent 1,2-dioxetane in polymer blends.

We report a versatile mechanophore exhibiting a vividly detectable, light‐regulable multicolor mechanochromism. Such optical features rely on the synergistic coupling of mechanochromic bis‐rhodamine (Rh) and photochromic bisthienylethene (BTE). Poly(methyl acrylate)s incorporating this bis‐mechanophore can be mechanically activated under sonication. The relative distribution of the two distinctly colored and fluorescent Rh ring‐opening products is altered with different magnitudes of applied force. Orthogonal use of the photochromic reaction of the BTE core can strengthen the mechanochromism and gate the mechanofluorescence in polymers. Due to increased conjugation offered by the BTE linker, both force‐ and light‐induced optical signals display high contrast. Combined DFT simulated and experimental results reveal that the three subunits (two Rhs and one BTE) in this chromophore are activated sequentially, thus generating switchable three‐colored forms and gradient optical responses.

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A new type of C 3 -symmetric aza-polycyclic aromatic hydrocarbon (PAH) discs attached with chiral alkoxyl chains is developed and explored as circularly polarized luminescence (CPL)-active materials with selective control and switching of chiroptical properties. Supramolecular polymerization of these PAHs is studied experimentally and theoretically. With the aid of weak hydrogen bonding and CH•••π interactions, these chromophores have strong tendency to form anisotropic chiral aggregates both in solutions and films. The well-controlled noncovalent interactions are critical for their excellent CPL performance. The resultant supramolecular polymers display a polarized emission band with the maximum g lum value up to 10 −2 . Benefited from the chiral supramolecular polymerization process and N-doping structure feature of the core, on/off CPL switching from these molecules can be reversibly realized by external stimuli including the change of temperature, solvent, and pH conditions. Our work shows that chiral supramolecular polymers from concise yet highly rigid and planar PAH cores are superbly suitable for exceptional CPL emission both in dilute solutions and bulk materials, with a promising switchable CPL feature, thereby unlocking new design possibilities.