Propargyl esters, HC CCH(2)OCOCnH(2n+1) (1: n = 3, 2: n = 5, 3: n = 9, and 4: n = 13), were polymerized using a [Rh(nbd)Cl](2) catalyst and cocatalyst in an appropriate solvent at 0 degrees C and 40 degrees C. Number average molecular weights, M-n of the resulting polymers, poly(1) poly(4), were 8000-54,000, and its dispersities (M-W/M-n)s and the yields were estimated to be 1.6-3.6 and ca. similar to 99%, respectively. These polymers were soluble in CHCl3, CH2Cl2, and THF, and insoluble in CH3OH and DMF. The amines, e.g., 2,6-dimethylpyridine and triethylamine worked well as the cocatalysts for the polymerization to give the yields, 93% and 88%, respectively. Further N,N-diethylaniline gave the maximum in cis%, 74%, although pyridine, aniline, pyrrole or imidazole did not work effectively. Remarkable line broadening phenomenon, LBP observed in the H-1 NMR spectra of poly(1) and poly(2) prepared at 0 degrees C or 40 degrees C, and poly(3) prepared at 40 degrees C was correlated with the polymerization temperature and the radical concentration generated in the polymer. The LBP was interpreted by the dipole dipole interaction between the protons in the polymer and unpaired electrons due to carbon radicals generated by the rotational scission of the cis C=C bonds during the polymerization. Their UV-vis spectral shape of poly(1) poly(4) depended on the polymerization temperature and/or the alkyl chain length in the polymer. The XRD powder patterns of poly(3) prepared at 0 degrees C, and poly(4)s prepared at 0 degrees C and 40 degrees C showed layer crystal structures with a slightly bent herringbone confirmed by molecular mechanics calculation. The lambda(max) values of poly(4) prepared at 40 degrees C in methanol showed 317 nm and 340 nm in the solution and on the alumina, respectively. (C) 2011 Elsevier Ltd. All rights reserved.