Abstract: | Cyclopolymerization of 1,6‐heptadiyne derivatives containing the bulky substitutents was carried out by metathesis catalyst systems. The catalytic activity of molybdenum (V) chloride (MoCl5) in homopolymerization is greater than that of the MoCl5‐cocatalyst system, and copolymerization is vice versa in catalytic activity. Newly synthesized homo‐ and copolymers were soluble in common organic solvents and could afford thin film by solution‐casting onto the indium–tin oxide coated glass substrate. The NMR, Fourier transform infrared spectroscopic, and UV–visible spectra indicated that these polymers have a linear conjugated cyclic polyene structure having a bulky substitutent as a pendant group. The number‐average molecular weight of these polymers was in the range of 2.4–6.27 × 103. The copolymers exhibited a relatively higher molecular weight than that of the homopolymers. The copolymers were stable up to 380 °C. The electrical conductivities of the I2‐doped copolymer thin film by the four‐point probe method and surface plasmon resonance spectroscopy were about 500 and 600 S/cm, respectively. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 958–964, 2002 |