Abstract: A method of making polyolefin with a target melt flow index and melt flow rate is disclosed. The method polymerizes one or more olefinic monomers in a single reactor containing a bicomponent catalyst system. The catalyst system includes a first catalyst component and a second catalyst component each characterized by a catalyst productivity and a chain-transfer-agent response. The single reactor has a chain-transfer-agent concentration and a temperature. The productivity of the second catalyst component is substantially different temperature dependent than that of the first catalyst component. The chain-transfer-agent response of the second catalyst component is substantially different sensitive than that of the first catalyst component. The temperature of the reactor is adjusted so that the melt flow ratio approaches the target value. The chain transfer agent concentration in the reactor is adjusted so that the melt index approaches the target value.

Abstract: A falling film of water is applied around the periphery of a fluid bed olefin polymerization reactor to cool the wall and reduce the temperature in the fluid bed near the inside surface of the wall. Cooling has the effect of reducing static in the reactor, which in turn ameliorates a sheeting problem and can enhance production by facilitating control of the relation of the reactor temperature and the dew point of recycled gas. The process may be used concurrently with a gas cooling and condensing recycle system wherein at least some of the condensed recycle gas is injected in the vicinity of the internal wall surface.

Abstract: A falling film of water is applied around the periphery of a fluid bed olefin polymerization reactor to cool the wall and reduce the temperature in the fluid bed near the inside surface of the wall. Cooling has the effect of reducing static in the reactor, which in turn ameliorates a sheeting problem and can enhance production by facilitating control of the relation of the reactor temperature and the dew point of recycled gas. The process may be used concurrently with a gas cooling and condensing recycle system wherein at least some of the condensed recycle gas is injected in the vicinity of the internal wall surface.

Abstract: In a process for the in situ blending of polymers comprising contacting ethylene and one or more comonomers in two or more fluidized bed reactors with a catalyst system comprising (i) a magnesium/titanium based precursor containing an electron donor and (ii) a hydrocarbyl aluminum cocatalyst, the improvement comprising (A) increasing or decreasing the melt flow ratio and/or molecular weight of the blend by, respectively, decreasing or increasing the mole ratio of a precursor activator compound to the electron donor or (B) increasing or decreasing the bulk density of the blend by, respectively, increasing or decreasing the mole ratio of a precursor activator compound to the electron donor, both (A) and (B) subject to defined provisos including partial pre-activation of the precursor.

Abstract: A process comprising contacting ethylene and at least one alpha-olefin comonomer having with a transition metal based catalyst system in two fluidized bed reactors connected in series, in the gas phase, under polymerization conditions, with the proviso that a hydrocarbyl aluminum cocatalyst is introduced into the first reactor and a different hydrocarbyl aluminum cocatalyst or no cocatalyst is introduced into the second reactor.