New acetylene monomers, 6-{[(1-naphthylethynyl-4-phenyl)carbonyl]oxy}-1-pheny-1-hexyne (1), 2, 5-diethynyl-thiophene (3), and 4,4’-diethynylbiphenyl(6) were synthesized. Homopolymerization of 1 and copolycyclotrimerizations of 3and 6 with 1-heptyne and 1-octyne have been achieved with WCl_6- and TaCl_5-Ph_4Sn catalysts, respectively, giving solublelinear disubstituted polyacetylene (2) and hyperbranched polyarylenes (5 and 8) with high molecular weights (up to 1.2×10~5) in high yields (up to 98%). The trictures and properties of the polymers are characterized and evaluated by IR, NMR,TGA, UV, photoluminescence (PL), and electroluminescence (EL) analyses. All the polymers possess high thermal stabilityand emit strong blue ligh upon photoexcitation. The intensity of the emitted light is greater than that of poly(1-phenyl-1-octyne), a well-known highly luminescent disubstituted polyacetylene. Little aggregation-induced red shift in the PL wasobserved in the thin films of the polymers. By constructing a multi-layer EL device, high EL quantum yield (0.18%) has beenachieved in 2, which are the best results for substituted polyacetylenes attainable so far. (1), 2, 5-diethynyl-thiophene (3), and 4,4’-diethynyl- Homopolymerization of 1 and copolyclyl trimetazations of 3 and 6 with 1-heptyne and 1-octyne have been achieved with WCl_6- and TaCl_5-Ph_4Sn catalysts, respectively, giving soluble linear disubstituted polyacetylene (2) and hyperbranched polyarylenes (5 and The trictures and properties of the polymers are characterized and evaluated by IR, NMR, TGA, UV, photoluminescence (PL), (8) with high molecular weights up to 1.2x10-5 in high yields (up to 98% All the polymers possess high thermal stability and emit strong blue ligh upon photoexcitation. The intensity of the emitted light is greater than that of poly (1-phenyl-1-octyne), a well-known highly luminescent disubstituted Little aggregation-induced red shift in the PL wasobserved in the thin films of the polymers. By constructing a multi-layer EL device, high EL quantum yield (0.18%) has beenachieved in 2, which are the best results for substituted polyacetylenes attainable so far.