Research Abstract |
1) Synthesis and Properties of Novel Nitrogen-Containing Polyacetylenes Novel nitrogen-containing acetylenes such as N-Carbazolylacetylene(CA)and 3-indolyl-1-propyne(IP)were synthesized. CA was polymerized by WCIィイD26ィエD2 or WCIィイD26ィエD2-n-BuィイD24ィエD2Sn to give polymer (MィイD2wィエD21-4x10ィイD14ィエD1) in good yield. On the other hand, polymerization of IP by using [(nbd)RhCl] ィイD22ィエD2 afforded polymer having MィイD2wィエD2 of 1.3x10ィイD15ィエD1 in high yield. In the UV-visible spectrum, poly (CA) exhibited a large red shift (cutoff〜700nm) compared with that of poly (phenylacetylene). This result was attributed to widely conjugated main chain of the polymer. Poly (CA) showed a third-order susceptibility of 18x10ィイD1-12ィエD1 esu, a very large value among substituted polyacetylenes. 2) Synthesis and Properties of Poly (phenylacetylene) s Having Dialkylamino Groups Two phenylacetylenes having p-n-N, N-diethylamino and p-n-N, N-dibutylamino groups were polymerized by [(nbd) RhCl] ィイD22ィエD2-EtィイD23ィエD2N catalyst to give polymers in high yield. These polymers were soluble in CHClィイD23ィエD2. In the UV-visible spectra, they showed absorption maxima around 300-400 nm. Electrochemical doping of the polymer films resulted in the shift of the absorptions to a region around 680 nm, which was accompanied by a color change of the polymer films from green ocher to deep blue. 3) Photoluminescence and Electroluminescence of Substituted Polyacetylenes Electroluminescnescence (EL) and photoluminescence (PL) of various substituted polyacetylenes were examined. Intense green and blue EL were observed with poly (diphenylacetylene) derivatives and poly (1-alkyl-2-phenylacetylene) derivatives, respectively. On the other hand, monosubstituted acetylene polymers showed very weak PL and EL. The dependence of wavelength and intensity of PL and EL on the molecular structure of substituents were clarified. Upon intense excitation, remarkable spectral narrowing due to stimulated emission was also observed.
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