Patent classifications
C08F4/642
Producing polyolefin products
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: ##STR00001##
wherein R.sup.1 and R.sup.2 are each independently, phenyl, methyl, chloro, fluoro, or a hydrocarbyl group.
Process control for long chain branching control in polyethylene production
Polymerization process control methods for making polyethylene are provided. The process control methods include performing a polymerization reaction in a polymerization reactor to produce the polyethylene, where ethylene, and optionally one or more comonomers, in the polymerization reaction is catalyzed by an electron donor-free Ziegler-Natta catalyst and an alkyl aluminum co-catalyst. A melt flow ratio (I.sub.21/I.sub.2) of the polyethylene removed from the polymerization reactor is measured and an amount of long chain branching (LCB) of the polyethylene from the polymerization reactor is controlled by adjusting a weight concentration of the alkyl aluminum co-catalyst present in the polymerization reactor. In addition, an electron donor-free Ziegler-Natta catalyst productivity of the polyethylene being produced in the polymerization reactor is measured from which the amount of LCB of the polyethylene from the polymerization reactor is determined using the measured electron donor-free Ziegler-Natta catalyst productivity and a predetermined relationship between the electron donor-free Ziegler-Natta catalyst productivity and the LCB.
Process control for long chain branching control in polyethylene production
Polymerization process control methods for making polyethylene are provided. The process control methods include performing a polymerization reaction in a polymerization reactor to produce the polyethylene, where ethylene, and optionally one or more comonomers, in the polymerization reaction is catalyzed by an electron donor-free Ziegler-Natta catalyst and an alkyl aluminum co-catalyst. A melt flow ratio (I.sub.21/I.sub.2) of the polyethylene removed from the polymerization reactor is measured and an amount of long chain branching (LCB) of the polyethylene from the polymerization reactor is controlled by adjusting a weight concentration of the alkyl aluminum co-catalyst present in the polymerization reactor. In addition, an electron donor-free Ziegler-Natta catalyst productivity of the polyethylene being produced in the polymerization reactor is measured from which the amount of LCB of the polyethylene from the polymerization reactor is determined using the measured electron donor-free Ziegler-Natta catalyst productivity and a predetermined relationship between the electron donor-free Ziegler-Natta catalyst productivity and the LCB.
Dual catalyst composition
The present invention relates to a catalyst composition comprising: catalyst component A comprising a bridged metallocene compound with two indenyl groups, each indenyl being substituted with one or more substituents, wherein at least one of the substituent is an aryl or heteroaryl; catalyst component B comprising a bridged metallocene compound with a substituted or unsubstituted cyclopentadienyl group and a substituted or unsubstituted fluorenyl group; an optional activator; an optional support; and an optional co-catalyst. The present invention also relates to a polymerization process using said composition. The invention further relates to olefin polymers at least partially catalyzed by said catalyst composition and articles comprising said olefin polymers.
Polymerization using a spiral heat exchanger
This invention relates to a polymerization process for forming polymer comprising: contacting (typically in a solution or slurry phase), a monomer and a catalyst system in a reaction zone comprising at least one spiral heat exchanger and recovering polymer, wherein the monomer, the catalyst system and the polymer flow through the at least one spiral heat exchanger in a cross-flow direction relative to spirals of the at least one spiral heat exchanger.
Bis-imine titanium complex, catalytic system comprising said bis-imine titanium complex and process for the (co)polymertzation of conjugated dienes
Bis-imine titanium complex having general formula (I): wherein: R.sub.1 and R.sub.2, mutually identical or different, represent a hydrogen atom; or are selected from linear or branched, optionally halogenated, C.sub.1-C.sub.20 alkyl groups, preferably C.sub.1-C.sub.15, optionally substituted cycloalkyl groups; R.sub.3 and R.sub.4, mutually identical or different, represent a hydrogen atom; or are selected from linear or branched, optionally halogenated, C.sub.1-C.sub.20 alkyl groups, preferably C.sub.1-C.sub.15, optionally substituted cycloalkyl groups, optionally substituted aryl groups; X.sub.1, X.sub.2, X.sub.3 and X.sub.4, mutually identical or different, represent a halogen atom such as chlorine, bromine, iodine; or are selected from linear or branched C.sub.1-C.sub.20 alkyl groups, preferably C.sub.1-C.sub.15, —OCOR.sub.5 groups or —OR.sub.5 groups wherein R.sub.5 is selected from linear or branched C.sub.1-C.sub.20 alkyl groups, preferably C.sub.1-C.sub.15; or represent an acetylacetonate group (acac); provided that when R.sub.1 and R.sub.2 represent a methyl group and X.sub.1, X.sub.2, X.sub.3 and X.sub.4 represent a chlorine atom, R.sub.3 and R.sub.4 are different from 2,6-di-isopropylphenyl. ##STR00001##
CURABLE COMPOSITIONS COMPRISING UNSATURATED POLYOLEFINS
The present disclosure relates to unsaturated polyolefins and processes for preparing the same. The present disclosure further relates to curable formulations comprising the unsaturated polyolefins that show improved crosslinking.
CURABLE COMPOSITIONS COMPRISING UNSATURATED POLYOLEFINS
The present disclosure relates to unsaturated polyolefins and processes for preparing the same. The present disclosure further relates to curable formulations comprising the unsaturated polyolefins that show improved crosslinking.
Ligand compound, transition metal compound, and catalyst composition including the same
The present invention provides a novel ligand compound, a transition metal compound and a catalyst composition including the same.
Ligand compound, transition metal compound, and catalyst composition including the same
The present invention provides a novel ligand compound, a transition metal compound and a catalyst composition including the same.