Patent classifications
C08F4/65925
BIMODAL LINEAR LOW DENSITY POLYETHYLENE COPOLYMER
Provided are bimodal linear low density polyethylene copolymers (B-LLDPE copolymers) that have a combination of improved properties comprising at least one processability characteristic similar or better than that of an unblended monomodal ZN-LLDPE and a dart impact property similar or better than that of an unblended monomodal MCN-LLDPE. For the various aspects, the B-LLDPE copolymer has a density from 0.8900 to 0.9300 g/cm.sup.3; a melt index (I.sub.2) from 0.1 g/10 min. to 5 g/10 min.; a M.sub.z from 600,000 to 1,900,000 g/mol; and a SHI from 5.35 to 75 η*(1.0)/η*(100). The B-LLDPE copolymer can be further characterized by a first melt flow ratio (I.sub.21/I.sub.2) from 32 to 140 and a first molecular weight ratio (M.sub.z/M.sub.w) from 4.5 to 11.
Ethylene/1-butene copolymer having excellent processability
Provided is an ethylene/1-butene copolymer having excellent processability and stress cracking resistance. The ethylene/1-butene copolymer according to the present invention may be applied to a high-pressure resistant heating pipe, a PE-RT pipe, a large diameter pipe, etc.
Ethylene/1-butene copolymer having excellent processability
Provided is an ethylene/1-butene copolymer having excellent processability and stress cracking resistance. The ethylene/1-butene copolymer according to the present invention may be applied to a high-pressure resistant heating pipe, a PE-RT pipe, a large diameter pipe, etc.
Process for preparing catalysts and catalyst compositions
Disclosed are support-activators and catalyst compositions comprising the support-activators for polymerizing olefins in which the support-activator includes clay heteroadduct, prepare from a colloidal phyllosilicate such as a colloidal smectite clay, which is chemically-modified with a heterocoagulation agent. By limiting the amount of heterocoagulation reagent relative to the colloidal smectite clay as described herein, the smectite heteroadduct support-activator is a porous and amorphous solid which can be readily isolated from the resulting slurry by a conventional filtration process, and which can activate metallocenes and related catalysts toward olefin polymerization. Related compositions and processes are disclosed.
Process for preparing catalysts and catalyst compositions
Disclosed are support-activators and catalyst compositions comprising the support-activators for polymerizing olefins in which the support-activator includes clay heteroadduct, prepare from a colloidal phyllosilicate such as a colloidal smectite clay, which is chemically-modified with a heterocoagulation agent. By limiting the amount of heterocoagulation reagent relative to the colloidal smectite clay as described herein, the smectite heteroadduct support-activator is a porous and amorphous solid which can be readily isolated from the resulting slurry by a conventional filtration process, and which can activate metallocenes and related catalysts toward olefin polymerization. Related compositions and processes are disclosed.
Particle size control of metallocene catalyst systems in loop slurry polymerization reactors
Catalyst compositions containing a metallocene compound, a solid activator, and a co-catalyst, in which the solid activator or the supported metallocene catalyst has a d50 average particle size of 15 to 50 μm and a particle size distribution of 0.5 to 1.5, can be contacted with an olefin in a loop slurry reactor to produce an olefin polymer. A representative ethylene-based polymer produced using the catalyst composition has excellent dart impact strength and low gels, and can be characterized by a HLMI from 4 to 10 g/10 min, a density from 0.944 to 0.955 g/cm.sup.3, a higher molecular weight component with a Mn from 280,000 to 440,000 g/mol, and a lower molecular weight component with a Mw from 30,000 to 45,000 g/mol and a ratio of Mz/Mw ranging from 2.3 to 3.4.
Particle size control of metallocene catalyst systems in loop slurry polymerization reactors
Catalyst compositions containing a metallocene compound, a solid activator, and a co-catalyst, in which the solid activator or the supported metallocene catalyst has a d50 average particle size of 15 to 50 μm and a particle size distribution of 0.5 to 1.5, can be contacted with an olefin in a loop slurry reactor to produce an olefin polymer. A representative ethylene-based polymer produced using the catalyst composition has excellent dart impact strength and low gels, and can be characterized by a HLMI from 4 to 10 g/10 min, a density from 0.944 to 0.955 g/cm.sup.3, a higher molecular weight component with a Mn from 280,000 to 440,000 g/mol, and a lower molecular weight component with a Mw from 30,000 to 45,000 g/mol and a ratio of Mz/Mw ranging from 2.3 to 3.4.
Process for Preparing a Transition Metal Compound
The present invention relates to a process for preparing a transition metal compound. Specifically, the present invention relates to a process for preparing a transition metal compound having a non-bridged, asymmetric biscyclopentadienyl group that can be used in the preparation of a catalyst for olefin polymerization. The process for preparing a transition metal compound according to an embodiment of the present invention is capable of conveniently preparing a transition metal compound having a non-bridged, asymmetric biscyclopentadienyl group.
Process for Preparing a Transition Metal Compound
The present invention relates to a process for preparing a transition metal compound. Specifically, the present invention relates to a process for preparing a transition metal compound having a non-bridged, asymmetric biscyclopentadienyl group that can be used in the preparation of a catalyst for olefin polymerization. The process for preparing a transition metal compound according to an embodiment of the present invention is capable of conveniently preparing a transition metal compound having a non-bridged, asymmetric biscyclopentadienyl group.
DUAL METALLOCENE POLYETHYLENE WITH IMPROVED PROCESSABILITY FOR LIGHTWEIGHT BLOW MOLDED PRODUCTS
Ethylene-based polymers having a density of 0.952 to 0.968 g/cm3. 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.