Chromophores in polymers

Methods based on radiationless transfer between chromophores in polymers can give information on local conformation and structure in blends but they are unable to give direct values of interaction parameters... 

To determine the usefulness and limits of the TICT chromophore as a fluorescence probe, we have to study the basic photophysies of the chromophore in polymers. The objective of this study is to examine the rotational motion of the amino group in polymer bonded 4-(N,N-dlmethylamino)benzoate (DMaB) chromophore in polymer solutions. The effects of polymer concentration, temperature and pressure on the TICT phenomenon of DMAB in the PMMA side chain were compared with those of a small molecular model compound, ethyl N,N-dimethylamino-benzoate, in solution. Our concern is to have an inside look into how polymeric environment influences the TICT phenomenon. 

Absorption and emission spectra of radical copolymer of methyl methacrylate wi h N,N-dimethylaminobenzoyloxyethylmethacrylate ( < 0.017=, Mn = 3 X 10 )(l) and ethyl N,N-dlmethylaminobenzoate (ll) are compared in Figure 2. Except for a small red shift ( 3 nm) in I, the absorption spectra are almost identical. Although the presence of a ground state dimer or solute-solvent complex is known for N,N-dimethylaminobenzonitrile, the best studied TICT compound, there seems to be no such complications for the present studies. This is a favorable condition to study the TICT chromophore in polymers since polymers tend to enhance complicated molecular association even in extremely dilute solution [12] which overshadows the aimed photophysical phenomenon. 

The proximity of the chromophores in polymers favours the formation of intramolecular excimers. Since excimer formation takes place at the expense of other photophysical and photochemical processes, it has been suggested that wherever excimer formation is possible the photochemistry of the polymer is likely to be strongly affected. 

ROOHs are the most dangerous chromophores in polymer stabilization and are homolyzed thermally by UV radiation and ions of transition metals. 

Early work on the mechanically induced deformation of supramolecular assemblies of chromophores in polymer matrices was inspired by the surprising discovery that solid-state tensile deformation of blends of minute amounts of the highly... 

Dyes and Chromophores in Polymer Science, First Edition. Edited by Jacques Lalevee and Jean-Pierre Fouassier. ISTE Ltd 2015. Published by ISTE Ltd and John Wiley Sons, Inc. 

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