Résumé : Syntheses of poly(9,9-dialkylfluorene-2,7-vinylene)s (PFVs, alkyl=n-hexyl, n-octyl, 2́-ethylhexyl) and poly(N-alkylcarbazole-2,7-vinylene)s (PCVs, alkyl=n-octyl, 9́-heptadecanyl) by acyclic diene metathesis (ADMET) polymerization using Ru-carbene complexes have been explored. The polymerizations in the presence of Ru(CHPh)(Cl)2(IMesH 2)(PCy3) and Ru(CH-2-OiPr-C 6H4)(Cl)2(IMesH2) [Cy= cyclohexyl, IMesH2=1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene] afforded relatively high molecular weight PFVs, PCV (alkyl=9́-heptadecanyl) with unimodal molecular weight distributions, and the olefinic double bonds in the resultant polymers possessed highly trans regularity in all cases. The resultant defect-free PFVs possessed higher absolute quantum yields (φ=92-99%) than those reported previously, whereas no significant differences in the UV-vis and the fluorescent spectra (absorption bands,peak maxima) in the resultant PFVs were observed as an effect of alkyl side chain in the 9-position. The UV-vis and the fluorescence spectra in the PCV were similar to those in the PFVs, indicating that the replacement (from fluorene to carbazole) does not affect the observed spectra; the resultant PCV also possessed remarkable absolute quantum yield (φ=86%). © 2009 American Chemical Society.