Visualization and quantitative evaluation of covalent bond scission in polymeric materials are highly important for understanding failure, fatigue, and deterioration mechanisms and improving the lifetime, durability, toughness, and reliability of the materials. The diarylbibenzofuranone-based mechanophore radical system enabled, through electron paramagnetic resonance spectroscopy, in situ quantitative evaluation of scission of the mechanophores and estimation of mechanical energy induced along polymer chains by external forces. The coagulation of polymer solutions by freezing probably generated force but did not cleave the mechanophores. On the other hand, cross-linking led to efficient propagation of the force of more than 80 kJ mol(-1) to some mechanophores, resulting their cleavage and generation of colored stable radicals. This mechanoprobe concept has the potential to elucidate other debated issues in the polymer field as well.

Visualization and quantitative evaluation of covalent bond scission in polymeric materials are highly important for understanding failure, fatigue, and deterioration mechanisms and improving the lifetime, durability, toughness, and reliability of the materials. The diarylbibenzofuranone-based mechanophore radical system enabled, through electron paramagnetic resonance spectroscopy, in situ quantitative evaluation of scission of the mechanophores and estimation of mechanical energy induced along polymer chains by external forces. The coagulation of polymer solutions by freezing probably generated force but did not cleave the mechanophores. On the other hand, cross-linking led to efficient propagation of the force of more than 80 kJ mol À1 to some mechanophores, resulting their cleavage and generation of colored stable radicals. This mechanoprobe concept has the potential to elucidate other debated issues in the polymer field as well.

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Organic/inorganic nanohybrid materials composed of terthiophenes and imogolite were prepared by means of specific surface interaction between a phosphonic acid group in terthiophene derivatives and aluminol groups on the surface of imogolite. The new materials were investigated by FTIR, UVvis absorption, fluorescence spectroscopy, TEM observation, nitrogen adsorptiondesorption, and IV measurement. Addition of terthiophene of phosphonic acid derivatives into imogolite brought some changes in absorption and photoluminescence spectra, suggesting the formation of H-type aggregate on imogolite surface. The analysis of UVvis spectra and nitrogen adsorptiondesorption data provided insight into the effect of molecular structure of terthiophenes on the adsorption and aggregation behaviors on the imogolite surface. In addition, a significant enhanced current flow was observed through imogolite film when imogolite was chemisorbed by electron-withdrawing terthiophenes. In contrast, current flow decreased as the electron-donating terthiophene was chemisorbed on imogolite. A possible mechanism for such phenomena is discussed.Organic electronic devices made up from small molecules of dye neatly linked by self-assembly to solid support are vital components in light energy conversions systems, optical devices, and sensors.1,2 The self-assemblies of molecules are widely found in nature, for instance, chlorophylls which are embedded in the thylakoid membranes of chloroplasts are specifically arranged in rod-shaped aggregate and act as an efficient light-harvesting system for photosynthesis.36 Recently, there has been considerable research interest focused on the study of photo-physicochemical properties, aggregations, and absorption behavior of dye molecules on the surface of inorganic materials. These studies can provide invaluable information that serves as guidance for fabrication of highperformance dye-based electronic devices.710 Such organic/ inorganic hybrid nanomaterials of the dye/solid support aggregates are expected to demonstrate novel nanotechnological applications that the corresponding monomeric dye could not perform.11,12 Nevertheless, the main challenge in this field remains preparation of a stable dye/solid support aggregate with adjustable aggregation structure on inorganic material surfaces.Generally, most dye molecules can self-assemble and adsorb on inorganic material surfaces through simple physisorption. However, given the fundamental and practical significance of better control over the adsorption and aggregation state of dye molecules on solid support, many research groups are involved in the effort to synthesize novel dye structures with anchoring groups attached. The strategy of attaching anchoring group into the dye is very important, in a sense that one can adjust the distance of dye from the surface, controlling the aggregation state of dye, as well as for chemical surface modification. 9 Additionally, it is possible to graft a variety of functionalized and photoactive species (porphyrins, phthalocya...