The synthesis and polymerization of (E)-p-[(p-methoxyphenyl)-2-ethenyl]-phenylacetylene was carried out with a homogeneous vanadium acetylacetonate/aluminum triethyl catalyst system, a his(rhodium chloride cycloocta-1,5-diene) complex, and a palladium/trimethylsilyl complex. In all cases, the main fraction was a polymer with a stereoregular structure. The polymerization with the vanadium catalyst gave a polymer fraction in a low yield. The polymerization of (E)-p-[(p-methoxyphenyl)-2ethenyl]-phenylacetylene with the soluble rhodium complex gave a polymer in a high yield. The soluble palladium/chlorotrimethylsilane complex gave a polymer in a good yield. On the basis of the spectroscopic data, the poly{(E)-p-[(p-methoxyphenyl)-2ethenyl]-phenylacetylene)} obtained, in all cases, showed a cis-transoidal stereoregular structure. The molecular mass of poly{(E)-p-(p-methoxyphenyl)-2-ethenyl]-phenylacetylene)} was determined by the matrix-assisted laser desorption/ionization time-of-flight technique. The kinetics of the reaction were analyzed. (c) 2005 Wiley Periodicals.