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A novel technique called disrelation spectroscopic imaging describes the process of identifying an area where a coordinated or out-of-phase change in pattern of spectral absorbance occurs. Disrelation mapping can be viewed as a spatial filter based on the well-established two-dimensional (2D) correlation function to highlight specific areas where disrelated variation occurs between ν and ν. Disrelation intensity develops only if the spectral absorbance measured at ν and ν vary out of phase with each other within a specific spatial area. The disrelation mapping locates regions where absorbance varies in a dissimilar manner because of the contribution from species of different physical or chemical origins. Consequently, it becomes possible to probe onset of molecular interactions or presence of intermediate forms between components, which is not fully detected by the conventional visualizations based on a single wavenumber. Data analysis using disrelation mapping applied to Fourier transform infrared (FT-IR) spectroscopic images is presented in this study. Data sets of FT-IR spectroscopic images of blends of poly(methyl methacrylate) (PMMA) and polyethylene glycol (PEG) were subjected to the disrelation mapping. It was found that the disrelation intensity between 1730 and 1714 cm becomes especially acute around the spatial boundary between PMMA and PEG domains within the studied blend sample. Thus the band at 1730 cm most likely represents the C=O stretching mode of the C=O···H-O species due to the intermolecular hydrogen bonding between PMMA and PEG. The appearance of such disrelation is more noticeable in the PEG-rich region, for the PEG with low molecular weight. Consequently, it suggests that the blends of PMMA and PEG are partially miscible at the molecular level and these intermolecular interactions are affected by the quantity of the terminal -OH groups of the PEG.

We investigated the initial photooxidation mechanism leading to reactive radical formation of polythiophene derivatives by focusing on the differences in the photochemical behaviors of photounstable poly(3-hexylthiophene) (P3HT) and photostable poly (3-octyloxythiophene) (P3OOT). Electron spin resonance measurements revealed that the [P3HT] + · (formed by oxygen doping) decayed, whereas no change was observed in the photostable [P3OOT] + · after light irradiation. Furthermore, the absorption decrease of the [P3HT] + · (P3HT) was suppressed by superoxide dismutase. Therefore, the oxygen dopant is superoxide, which might also initiate the oxidation of P3HT. The photochemical difference between P3HT and P3OOT can be explained by the reaction of an α-proton with superoxide in the case of P3HT.

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No vinyl ether by‐products are formed in the palladium(0)‐complex catalyzed hydroalkoxylation of hexafluoropropene (see scheme). Saturated hydrofluoroethers are selectively synthesized with alcohols or phenols under neutral conditions in the presence of [Pd(PPh3)4]/dppb. dppb=1,4‐bis(diphenylphosphanyl)butane.