A process for the preparation of polyolefins by polymerizing olefins at temperatures of from 20 to 200 C. and pressures of from 0.1 to 20 MPa in the presence of a polymerization catalyst and an antistatically acting composition in a polymerization reactor, wherein the antistatically acting composition is a mixture comprising an oil-soluble surfactant and water and the use of an antistatically acting composition comprising an oil-soluble surfactant and water as antistatic agent for the polymerization of olefins at temperatures of from 20 to 200 C. and pressures of from 0.1 to 20 MPa in the presence of a polymerization catalyst.

The present disclosure provides methods of treating industrial processes with compositions, methods of manufacturing the compositions, and various anti-freezing compositions suitable for use in the industrial processes. The anti-freezing dispersant compositions may include, for example, sulfonated dispersants and winterization solvents. The anti-freezing dispersant compositions may prevent fouling in the industrial processes.

The present technology relates to a method of introducing a supported antistatic compound that does not comprise a transition-metal-based catalyst component for use in an olefin polymerization reactor. In some embodiments, the methods disclosed herein avoid the formation of polymer agglomerates in the reactor and minimize potentially negative effects on catalyst yield.

The present technology relates to a method of introducing a supported antistatic compound that does not comprise a transition-metal-based catalyst component for use in an olefin polymerization reactor. In some embodiments, the methods disclosed herein avoid the formation of polymer agglomerates in the reactor and minimize potentially negative effects on catalyst yield.

A polymerization catalyst system, a method of using the polymerization catalyst system, and a polymer produced with the catalyst system. The polymerization catalyst system has a non-metallocene catalyst and a metallocene catalyst. The metallocene catalyst has the formula: wherein R.sup.1 and R.sup.2 are each independently, phenyl, methyl, chloro, fluoro, or a hydrocarbyl group.

A polymerization catalyst system, a method of using the polymerization catalyst system, and a polymer produced with the catalyst system. The polymerization catalyst system has a non-metallocene catalyst and a metallocene catalyst. The metallocene catalyst has the formula: wherein R.sup.1 and R.sup.2 are each independently, phenyl, methyl, chloro, fluoro, or a hydrocarbyl group.

Systems and processes for controlling fouling in the manufacture of ethylene polymers and copolymers at high pressure. Disclosed is a high pressure polyethylene polymerization system comprising a reactor, a primary compressor, and a secondary compressor, the secondary compressor comprising: a) a first stage, wherein the first stage comprises at least two cylinders, and the discharge pipes of the at least two cylinders are fluidly connected by a first stage discharge cross-connect pipe; b) a second stage; c) an interstage; and d) a first cooler applied to the interstage piping starting at a location within 10 meters downstream of the first stage discharge cross-connect pipe.

Systems and processes for controlling fouling in the manufacture of ethylene polymers and copolymers at high pressure. Disclosed is a high pressure polyethylene polymerization system comprising a reactor, a primary compressor, and a secondary compressor, the secondary compressor comprising: a) a first stage, wherein the first stage comprises at least two cylinders, and the discharge pipes of the at least two cylinders are fluidly connected by a first stage discharge cross-connect pipe; b) a second stage; c) an interstage; and d) a first cooler applied to the interstage piping starting at a location within 10 meters downstream of the first stage discharge cross-connect pipe.

Bimodal high density polyethylene compositions can achieve an improved balance of stress crack resistance and processability by selecting the higher molecular weight and lower molecular weight components such that (1) the lower molecular weight component has a relatively high complementary density, which is a calculated property shown by the formula below, and (2) the higher molecular weight component of the composition has a moderately-low density and narrow molecular weight distribution. This combination of properties provides improved balance of stress crack resistance and processability without having to modify the properties of the higher molecular weight component.

Bimodal high density polyethylene compositions can achieve an improved balance of stress crack resistance and processability by selecting the higher molecular weight and lower molecular weight components such that (1) the lower molecular weight component has a relatively high complementary density, which is a calculated property shown by the formula below, and (2) the higher molecular weight component of the composition has a moderately-low density and narrow molecular weight distribution. This combination of properties provides improved balance of stress crack resistance and processability without having to modify the properties of the higher molecular weight component.