| abstract |
Highly stereospecific olefin polymers are obtained in enhanced yield in a continuous gas-phase fluid bed process for polymerizing alpha monoolefins employing a catalyst system comprising (a) a solid titanium-containing procatalyst, (b) an organoaluminum activator compound, and (c) a selectivity control agent, by continuously adding dialkylaluminum halide to the reactor during polymerization and conducting polymerization at a temperature of 0.1 to 5.0°C above the dew point temperature of the cycle gas in the reactor. |