PURPOSE: To prepare a highly stereoregular polyolefin without using an activator, by carrying out the polymerization in the presence of a catalyst comprising a halide of titanium or vanadium bonded to a carrier such as silica, alumina, etc. through oxygen atom and having an atomic valence lower than the highest one.
CONSTITUTION: Titanium tetrachloride or vanadium tetrachloride, etc. dissolved in a solvent, e.g. n-hexane, is added to a silica, alumina or silica-alumina carrier and reacted by heating. The solid portion is separated by filtration, dried, and reduced at 100W800°C to give a halide of titanium or vanadium bonded to the carrier through oxygen atom and having an atomic valence lower than the highest one. An olefin, e.g. propylene, is polymerized under nitrogen atmosphere in the presence of the catalyst prepared above to give the desired polymer.
SOGA KAZUO
TERANO MINORU
