Abstract
The polymerizability of two silylated acetylenic monomers, 3-trimethylsiloxy-1-propyne and 1-trimethylsilyl-1,4-pentadiyne was studied in the presence of combined catalyst iron(III) propanoate-triethylaluminium. To obtain an insight into the steric hindrance effect on the polymerization of this type of monomer, the polymerization of 3-trimethylsilyl-1-propyne, a more hindered monomer, was undertaken. A feature of this monomer is that its polymerization may not yield side-reactions. The polymerization of the first two monomers gave silylated polyacetylenic compounds with a molecular weight close to 10(5) and molecular weight distribution of 1,5-3, with a yield approaching 75%. By comparison, the polymer of 3-trimethylsilyl-1-propyne ended up with a lower yield, 5%, illustrating its lower reactivity. In all cases, a slightly stereospecific character of the polymer was observed. (C) 1996 Elsevier Science Ltd.