Ethylene-based polymers having a density of 0.952 to 0.968 g/cm.sup.3, a ratio of HLMI/MI from 185 to 550, an IB parameter from 1.46 to 1.80, a tan δ at 0.1 sec.sup.−1 from 1.05 to 1.75 degrees, and a slope of a plot of viscosity versus shear rate at 100 sec.sup.−1 from 0.18 to 0.28 are described, with low melt flow versions having a HLMI from 10 to 30 g/10 min and a Mw from 250,000 to 450,000 g/mol, and high melt flow versions having a HLMI from 30 to 55 g/10 min and a Mw from 200,000 to 300,000 g/mol. These polymers have the processability of chromium-based resins, but with improved stress crack resistance and topload strength for bottles and other blow molded products.

Ethylene-based polymers having a density of 0.952 to 0.968 g/cm.sup.3, a ratio of HLMI/MI from 185 to 550, an IB parameter from 1.46 to 1.80, a tan δ at 0.1 sec.sup.−1 from 1.05 to 1.75 degrees, and a slope of a plot of viscosity versus shear rate at 100 sec.sup.−1 from 0.18 to 0.28 are described, with low melt flow versions having a HLMI from 10 to 30 g/10 min and a Mw from 250,000 to 450,000 g/mol, and high melt flow versions having a HLMI from 30 to 55 g/10 min and a Mw from 200,000 to 300,000 g/mol. These polymers have the processability of chromium-based resins, but with improved stress crack resistance and topload strength for bottles and other blow molded products.

Embodiments of methods for producing a trimodal polymer in a solution polymerization process comprise three solution polymerization reactors organized in parallel or in series.

Embodiments of methods for producing a trimodal polymer in a solution polymerization process comprise three solution polymerization reactors organized in parallel or in series.

A rubber composition is based on at least one diene elastomer, a reinforcing filler, a crosslinking system and a hydrocarbon-based resin. The hydrocarbon-based resin has a number-average molecular weight (Mn) of between 700 and 1000 g/mol, an average molecular weight Mz of greater than 6000 g/mol and a polydispersity index (PI) of greater than 2.4.

Provided herein are metallocene-catalyzed polymer compositions that exhibit advantageous rheological properties, at least some of which are consistent with long-chain branching, as well as polymerization processes suitable for forming such polymer compositions. The polymer compositions may have both LCB index measured at 125° C. of less than 5; and phase angle δ at complex shear modulus G*=100,000 Pa of less than about 54.5°, as determined at 125° C. The polymer compositions of particular embodiments are reactor blends, preferably of ethylene copolymers (e.g., ethylene-propylene (EP) copolymers and/or ethylene-propylene-diene (EPDM) terpolymers). The reactor blend may include first and second copolymer components, which may differ in monomer content and weight-average molecular weight (Mw).

Provided herein are metallocene-catalyzed polymer compositions that exhibit advantageous rheological properties, at least some of which are consistent with long-chain branching, as well as polymerization processes suitable for forming such polymer compositions. The polymer compositions may have both LCB index measured at 125° C. of less than 5; and phase angle δ at complex shear modulus G*=100,000 Pa of less than about 54.5°, as determined at 125° C. The polymer compositions of particular embodiments are reactor blends, preferably of ethylene copolymers (e.g., ethylene-propylene (EP) copolymers and/or ethylene-propylene-diene (EPDM) terpolymers). The reactor blend may include first and second copolymer components, which may differ in monomer content and weight-average molecular weight (Mw).

The present invention relates to a novel Group 4 transition metal compound, a method for preparing the compound, a catalyst composition comprising the compound, and a method for preparing a polyolefin comprising performing a polymerization reaction of olefin monomers, in the presence of the catalyst composition. Since the Group 4 transition metal compound of the present invention exhibits an excellent catalytic activity in polyolefin synthesis reactions, as well as having excellent thermal stability, it can be used for polyolefin synthesis reactions at high temperatures, and by changing the type of a central metal and ligand, the weight average molecular weight of synthesized polyolefins and the octene content in the polymer can be controlled. Therefore, it can be effectively used in polyolefin synthesis processes in which grades are controlled.

The present invention relates to a novel Group 4 transition metal compound, a method for preparing the compound, a catalyst composition comprising the compound, and a method for preparing a polyolefin comprising performing a polymerization reaction of olefin monomers, in the presence of the catalyst composition. Since the Group 4 transition metal compound of the present invention exhibits an excellent catalytic activity in polyolefin synthesis reactions, as well as having excellent thermal stability, it can be used for polyolefin synthesis reactions at high temperatures, and by changing the type of a central metal and ligand, the weight average molecular weight of synthesized polyolefins and the octene content in the polymer can be controlled. Therefore, it can be effectively used in polyolefin synthesis processes in which grades are controlled.

Embodiments are directed to catalyst systems comprising at least one metal ligand complex and to processes for polyolefin polymerization incorporating the catalyst systems. The metal ligand complexes have the following structures: (I) ##STR00001##