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11.
Franco Cataldo 《Tetrahedron letters》2005,46(21):3665-3667
Polyynes solutions having as main components C6H2 and C8H2 can be prepared in hydrocarbon solvents by hydrolyzing calcium carbide in an NH4Cl aqueous solution containing Cu(I)/Cu(II) salts. The polyynes are released into a hydrocarbon solvent by acidification with concd. HCl. Heptane solutions with polyynes concentration as high as 0.1 M can be easily prepared. 相似文献
12.
Matthias H 《高分子科学》2005,(6):567-591
Polycyclotrimerization and polycoupling of acetylenic monomers respectively furnish hyperbranched polyarylenes and polyynes with high molecular weights(up to 1×10~6)in high yields(up to 99.9%).The polymers possess low intrinsic viscosities and high thermal stabilities,losing little of their weights when heated to>400℃.Upon pyrolysis at>800℃,the polymers graphitize with high char yields(up to 86%).Hyperbranched polyarylenes efficiently emit deep-blue to blue-green lights with fluorescence quantum yields up to 98% and strongly attenuate intense laser pulses with optical power-limiting performances superior to that of C_(60),a well-known optical lirniter.Poly(alkenephenylenes),poly(aroylarylenes)and polyynes are readily cross-linkable by UV irradiation,serving as excellent photoresist materials for the generation of patterns with nanometer resolution.Thin films of hyperbranched polyynes exhibit very high refractive indexes(n up to 1.86).The internal and terminal acetylene moieties of the polyynes readily form complexes with cobalt carbonyls,which can be transformed into soft ferromagnetic ceramics with high magnetic susceptibilities(M_s up to ca.118 emu/g)and near-zero magnetic losses. 相似文献