Luminescence and Optical Properties

Luminescence properties of and phenomena in polymer systems continues to be widely researched in connection with mechanisms of polymer degradation and stabilization, molecular dynamics, solubility, blend miscibility, and solar energy harnessing. A number of interesting reviews have appeared. Molecular dynamics of polymers in solution and in the solid state have been covered, as has excimer formation,photoresponsive polymers,behaviour of polymer gels, and photochromic phenomena. Photoisomerization of enzymes and model compounds has also been discussed in depth, with particular emphasis on proteins and synthetic polymers containing azo-compounds or spirobenzopyrans.  

Several interesting theoretical papers have appeared dealing with molecular dynamics and excimer formation in polymer systems. Frank and coworkers have developed a model to describe the transport of electronic excitation energy in polymer chains. The theory applies to an isolated chain with a small concentration of randomly placed chromophores, and a three-dimensional transport model was used to solve the problem which is based on a diagrammatic expansion of the transport Green function. (The Green function is related to time-dependent and photostationary depolarization and to transient and steady-state trap fluorescence.) The analysis is shown to be 

Macromol. Symp., 28th, 1982, 96. 

Photoresponsive membranes of cellulose-2,4-diacetate incorporating 6-nitro-l, 3, 3 -trimethylspiro-(2H-l-benzopyran-2,2 -indoline) have been prepared and chiroptical and fluorescence properties of optically active co-polymers of acenaphthalene with methyl acrylate/methacrylate have been investigated. Marked optical activity is induced in the aromatic units only for the co-polymer with methyl methacrylate. This difference in behaviour is associated with an overall higher main-chain flexibility and conformational freedom in acrylates compared with methacrylates. Photoisomerization in polyurethanes containing azo-links has been found to be dependent upon the thermal history of the polymer, and photoisomerization of linoleic acid and 

Steinburg and E. Haas, Jerusalem Symp. Quantum Chem. Biochem., 1982, 15 (Intramol. 

Optical and Luminescence Properties Several review articles of topical interest have appeared. Donor-acceptor interactions in charge-transfer complexes between low 

Fluorescence lifetimes of melamine-formaldehyde resins have been measured and concluded not to be important in the photodegradation of the resins.Circular dichroism studies on -polyCl phenyl-azobenzoyl-L-lysine) have shown that conformational changes are 

The dispersion of resonantly-enhanced Roman modes with excitation energy have been examined in Durham poly(acetylene). The results 

Photoisomerisation processes particularly those utilising an azo group continue to attract much interest. An azobenzene modified poly(jf-methyl L-glutamate-co-L-glutamic acid) has been prepared and 

Azobenzene and stilbene compounds have been examined as molecular 

Prokroky Vyrobe Ponziti Lepide Drevopriem, 1979, 4, 83. 

Dubois and A. Eranian, Plast. Electron Microelectron (J. Etud. Group. Primot. Connaiss Plast.), 1978, 187. 

Ciardelli, E. Chiellini, and C. Carlini, in Optically Active Polymers , Vol. 5 of Charged and Reactive Polymers, ed. E. Selegny, D. Reidel, Boston, 1979, p. 83. 

Chiellini, R. Solaro, F. Ciardelli, G. Galli, and A. Ledwith, Polym. Bull., 1980, 2, 577. 

Farina, G. D. Silvestro, and P. Sozzani, Makromol. Chem., Rapid Commun., 1981, 2, 51. 

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OPTICAL AND LUMINESCENCE PROPERTIES AND APPLICATIONS OF METAL COMPLEX-BASED POLYMERS... 

Morozov YV, Bazhulina NP, Karpeiskii MY, Ivanov VI and Kuklin AI, Optical and luminescent properties of vitamin B6 and its derivatives. III. Pyridoxannne and pyridoxamine-5 -phosphate, Biofizica, 11,228-36 (1966) CA 65 8935. Cited in Perrin Bases suppl. no. 7794 ref. M21. NB Also includes fluorescence data. 

The solution combustion synthesis method has proven to be a great technique to obtain various types of oxides at the nanometer scale and is used for a variety of technological applications, as can be seen in Table 2.1. This wide range of oxides is prepared with an eye on their magnetic, mechanical, dielectric, catalytic, optical and luminescent properties. 

IV. PHYSICAL AND CHEMICAL PROPERTIES A. Optical and Luminescent Properties... 

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