POLYMERIZATION OF 1-(1-NAPHTHYL)-1-PROPYNE BY NB AND TA CATALYSTS AND POLYMER PROPERTIES - EFFECTS OF THE 1-NAPHTHYL GROUP

1-(1-Naphthyl)-1-propyne polymerized in the presence of NbCl5-cocatalyst systems to give virtually selectively a new polymer ($) over bar M(w) ca.3x10(5)) in high yields. Catalysts based on TaCl5 produced mixtures of the polymer and cyclotrimers. The polymer was a pale-yellow solid soluble in various organic solvents (e.g., toluene, CHCl3), and formed a free-standing film on solution casting. The onset temperature of the weight loss of the polymer in air was ca. 340 degrees C, which is higher than that (280 degrees C) of poly(1-phenyl-1-propyne) [poly(1-PP)]. The oxygen permeability coefficient at 25 degrees C was 80 barrers and one order of magnitude higher than that of poly(1-PP). These results are explicable in terms of the steric effects of the 1-naphthyl group.