Abstract: Novel copolymers are described comprising ethylene and alpha-olefins having (a) a density (D) in the range 930-960/g/m3 (b) a melt index (MI2) in the range 0.1-3.5 g/10 min (c) a melt elastic modulus G? (G?=500 Pa) in the range 40 to 150 Pa, and (d) a ratio of complex dynamic shear viscosities ?*(0.1)/?*(100) in the range 1.5 to 5.5. The novel copolymers are particularly suitable for use as Polyethylenes of Raised Temperature Resistance (PE-RT) for use in hot water piping systems. The novel copolymers may be prepared by use of meltallocene catalyst systems. Pipes having a time to failure of ?500 hrs measured according to ISO 1167 at 110° C. and 2.6 MPa prepared in a single reactor are also disclosed.

Abstract: A propylene resin composition which is a three-component material is improved in rigidity, heat resistance, and impact resistance while maintaining a satisfactory balance among these and further improved in low-temperature (about ?30° C.) impact resistance. A propylene resin composition as described in the specification.

Abstract: The present invention relates to a method for the production of an ethylene/propylene/diene copolymer by means of solution polymerisation, and more specifically one for a copolymer whose main components are ethylene, propylene and diene monomers using a catalyst of a transition metal coordination compound; the constituent components and characteristics of the copolymer being as follows. The catalyst composition provided by the present invention, which is used to produce a copolymer of which (a) the ethylene content is from 30 wt. % to 80 wt. %, (b) the propylene content is from 19.9% to 60 wt. % and (c) the diene content is from more than 0 wt. % to 15 wt.

Abstract: Disclosed is a novel transition metal compound which is used for forming a metallocene catalyst for olefin polymerization. Specifically disclosed is a novel transition metal compound represented by the general formula below which enables to form a metallocene catalyst that has a balanced reactivity with ethylene and a comonomer selected from ?-olefins having 3-20 carbon atoms and enables to produce an ?-olefin polymer having a high molecular weight. Also specifically disclosed are a catalyst for olefin polymerization containing such a transition metal compound, and a method for producing a propylene/ethylene-?-olefin block copolymer wherein such a catalyst is used.

Abstract: Disclosed is a method of producing a polyolefin composition comprising contacting a metallocene pre-catalyst, co-catalyst, and a stoichiometric excess of a metal alkyl; adding a first olefin monomer; and polymerizing the first monomer for a time sufficient to form the polyolefin. The method allows for the use of minimum amounts of activating co-catalyst and metallocene pre-catalyst. Also disclosed is a method of producing a block polyolefin composition comprising contacting a metallocene pre-catalyst, a co-catalyst, and a stoichiometric excess of a metal alkyl; adding a first olefin monomer; polymerizing the first monomer for a time sufficient to form the polyolefin; adding a second monomer; and polymerizing the second olefin monomer for a time sufficient to form said block polyolefin composition. Also disclosed are amorphous atactic polymer and copolymer compositions made according to the present invention.

Abstract: Catalysts useful for polymerizing olefins are disclosed. The catalysts comprise an activator and a Group 4 metal complex that incorporates a dianionic, tridentate 2-(2-aryloxy)quinoline or 2-(2-aryloxy)dihydroquinoline ligand. In one aspect, supported catalysts are prepared by first combining a boron compound having Lewis acidity with excess alumoxane to produce an activator mixture, followed by combining the activator mixture with a support and the tridentate, dianionic Group 4 metal complex. The catalysts are easy to synthesize, support, and activate, and they enable facile production of high-molecular-weight polyolefins.

Abstract: A copolymer of ethylene and an alpha-olefin, said copolymer having a (a) density>0.930 g/cm3, (b) melt index (g/10 min)>4, (c) molecular weight distribution (MWD)>3.0, and (d) FNCT>250 hours., and is described suitable for use in rotomoulding applications. In particular the novel copolymers result in improved impact strength, improved permeation resistance and improved environmetal stress crack resistance and may suitably be prepared by use of metallocene catalysts.

Abstract: The present invention discloses efficient methods for preparing substituted cyclopentadienyl-fluorenyl catalyst components having a mono-carbon bridge.

Abstract: Described is a cyclobutene polymer comprising: monomeric units of cyclobutene, said cyclobutene having at least one fused ring system substituted thereon, said polymer comprising not more than 10 mol percent ring-opened units of said cyclobutene; and said polymer having a molecular weight of at least 1,000; said polymer optionally copolymerized with a comonomer to form a copolymer therewith. Compositions thereof and methods of making the same are also described.

Abstract: The present invention provides dual catalyst systems and polymerization processes employing these dual catalyst systems. The disclosed polymerization processes can produce olefin polymers at higher production rates, and these olefin polymers may have a higher molecular weight and/or a lower melt index.

Abstract: The present invention provides dual catalyst systems containing a metallocene catalyst and a hydrogen scavenging catalyst, and polymerization processes employing these dual catalyst systems. Due to a reduction in hydrogen levels in the polymerization processes, olefin polymers produced from these polymerization processes may have a higher molecular weight, a lower melt index, and higher levels of unsaturation.

Abstract: The present invention generally relates to a process that selectively polymerizes ethylene in the presence of an alpha-olefin, and a precatalyst and catalyst useful in such processes.

Abstract: Improved thermoplastic polymer blend compositions comprising an isotactic polypropylene component and an alpha-olefin and propylene copolymer component, said copolymer comprising crystallizable alpha-olefin sequences. In a preferred embodiment, improved thermoplastic polymer blends are provided comprising from about 35% to about 85% isotactic polypropylene and from about 30% to about 70% of an ethylene and propylene copolymer, wherein said copolymer comprises isotactically crystallizable propylene sequences and is predominately propylene. The resultant blends manifest unexpected compatibility characteristics, increased tensile strength, and improved process characteristics, e.g., a single melting point.

Abstract: A cationic polymerization process for isoolefins using a zinc halide initiator. The zinc halide initiator is added to a solution of the isoolefin in a suitable solvent, preferably a halocarbon solvent. Polymerization reactions are normally conducted at temperatures high enough to allow the zinc halide initiator to dissolve in the solution. An alkyl halide activator may optionally be used and is preferably added to the solution prior to the zinc halide initiator. A multiolefin may optionally be present in the solution. The process is particularly useful in the formation of isoolefin homopolymers and co-polymers of isoolefins and multiolefins, such as butyl rubber.

Abstract: A process is taught, comprising polymerizing ethylene in the presence of a catalyst to form a crystalline ethylene-based polymer having a crystallinity of at least 50% as determined by DSC Crystallinity in a first reactor or a first part of a multi-part reactor and reacting the crystalline ethylene-based polymer with additional ethylene in the presence of a free-radical initiator to form an ethylenic polymer in at least one other reactor or a later part of a multi-part reactor.

Abstract: A composition having excellent transparency, flexibility, rubber elasticity, thermal resistance, impact resistance, abrasion resistance and the like, a composition having excellent rigidity and impact resistance as well as excellently balanced in whitening resistance, abrasion resistance and heat sealability, and a composition having excellent rubbery properties, thermal resistance, abrasion resistance and flexibility are provided. A composition comprising a specific propylene•?-olefin copolymer for which, in a signal chart measured by 13C-NMR and predetermined such that the peak present at the highest magnetic field among the signals originating from CH (methine) of the constituent unit derived from an ?-olefin having 4 to 20 carbon atoms is to be at 34.4 ppm, an absorption intensity A at about 22.0 to 20.9 ppm and an absorption intensity B at about 19.0 to 20.6 ppm satisfy the following relational expressions (i) and (ii) with respect to an absorption intensity C at about 19.0 to 22.

Abstract: Disclosed are a transition metal complex having a high catalytic activity for the preparation of an ethylene homopolymer or a copolymer of ethylene and ?-olefin and a catalyst composition comprising the same. More specifically, there are provided a transition metal complex having, around a group IV transition metal, a cyclopentadiene derivative and at least one aryl oxide ligand with a heterocyclic aryl derivative substituted at the ortho-position thereof, with no crosslinkage between the ligands, a catalyst composition comprising the transition metal complex and an organoaluminum compound or boron compound as cocatalyst, and a method for the preparation of high molecular weight ethylene homopolymers or copolymers of ethylene and ?-olefin using the same.

Abstract: A complex comprising a ligand of formula (I), wherein each R1, which may be the same or different, is hydrogen, an optionally substituted C1-20 hydrocarbyl group, N(R5)2, silyl, siloxy; an optionally substituted heteroaryl group, an optionally substituted heterocyclyl group or two R1 groups on adjacent carbon atoms taken together may form an optionally substituted 5- to 8-membered fused ring; each R2, which may be the same or different is hydrogen, is hydrogen, an optionally substituted C1-20 hydrocarbyl group, N(R5)2, silyl, siloxy; an optionally substituted heteroaryl group, or an optionally substituted heterocyclyl group; R3, which binds to the 6-membered ring of the indenyl group, is —(Si(R5)2)p—, where p is 1 or 2, —(C(R5)2)n- where n is an integer of 2 or more; each R4 which may be the same or different, is hydrogen, an optionally substituted C1-20 hydrocarbyl group, N(R5)2, silyl, siloxy, an optionally substituted heteroaryl group, an optionally substituted heterocyclyl group or two R4 groups on adjace

Abstract: This invention relates to new transition metal complexes for use in olefin polymerization and oligomerization. The active complex is a pyridine amide having a metallocenyl substituent as part of the ligand structure. The invention also relates to novel precursors for the ligand systems of such complexes obtained from metallocenyl-substituted pyridine compounds through sequences involving addition-condensation or lithium-halogen exchange (with subsequent metathesis) reactions.

Abstract: This invention relates to the field of olefin polymerization catalyst compositions, and methods for the polymerization and copolymerization of olefins, including polymerization methods using a supported catalyst composition. In one aspect, the present invention encompasses a catalyst composition comprising the contact product of a first metallocene compound, a second metallocene compound, at least one chemically-treated solid oxide, and at least one organoaluminum compound. The new resins were characterized by useful properties in impact, tear, adhesion, sealing, extruder motor loads and pressures at comparable melt index values, and neck-in and draw-down.

Abstract: A copolymer of ethylene, a catalyst system suitable to prepare the copolymer, and a process to prepare such copolymer are described. The copolymer comprises from 60 to 80% by weight of ethylene and from 20 to 40% by weight of at least one first ?-olefin comonomer having n carbon atoms and at least one second ?-olefin comonomer having (n?1) carbon atoms, n being from 4 to 13, has a polydispersity Mw/Mn equal to or lower than 3.5, and a density from 0.855 to 0.880 g/cm3. The copolymer is obtained by subjecting ethylene and said at least one first ?-olefin comonomer to a polymerization stage in the presence of a catalyst system capable of forming a copolymer of ethylene and said at least one first ?-olefin comonomer having n carbon atoms, while forming the second ?-olefin comonomer having (n?1) carbon atoms.

Abstract: The present invention relates to a transition metal complex useful as a transition metal catalyst in the preparation of an ethylene homopolymer or a copolymer of ethylene and an ?-olefin, a catalyst composition comprising the same and a process of preparing an ethylene homopolymer or a copolymer of ethylene and an ?-olefin using the same. More particularly, it relates to a transition metal complex having a cyclopentadiene derivative and at least one phenyl oxide ligand substituted at the 2-position of phenyl with, for example, a silyl group having a C1-C30 hydrocarbon group or a C1-C20 hydrocarbon group, around a group IV transition metal, with no crosslinkage between the ligands, a catalyst composition comprising the transition metal complex and a cocatalyst selected from the group consisting of an aluminoxane and a boron compound, and a process for preparing an ethylene homopolymer or a copolymer of ethylene and an ?-olefin using the same.

Abstract: Metallocene compounds of the invention are useful as olefin polymerization catalysts or catalyst components. Olefin polymerization processes of the invention involve an olefin polymerization catalyst containing the metallocene compound. In detail, the olefin polymerization catalysts can catalyze with high polymerization activity the production of olefin polymers having high melt tension, excellent mechanical strength and good particle properties, and the olefin polymerization processes involve the catalysts. Ethylene polymers according to the invention are obtained by the polymerization processes and have higher processability and easy-opening properties and particularly excellent mechanical strength compared to conventional ethylene polymers. Thermoplastic resin compositions of the invention contain the ethylene polymers.

Abstract: This invention discloses an improved process which employs mixed alpha-olefins as feed over activated metallocene catalyst systems to provide essentially random liquid polymers particularly useful in lubricant components or as functional fluids.

Abstract: A process for the polymerization of olefins using a metal complex of group 3, 4, 5, 6, 7, 8, 9 or 10 of the Periodic Table comprising at least one group C?NR1, C?PR1, C?O, C?S or a heteroaromatic ring system containing at least one atom from the group consisting of N, P, O and S, can be used for controlling the width of the molar mass distribution of the resulting polymers.

Abstract: A two-stage cascade polymerization process for the production of multimodal polyethylene film resins with improved bubble stability is provided. The process comprises polymerizing ethylene or a mixture of ethylene and a C4-8 ?-olefin in two reactors arranged in series using a mixed single-site catalyst comprised of a bridged and a non-bridged indenoindolyl transition metal complex to form a multimodal polyethylene resin comprised of a lower molecular weight, higher density component and a higher molecular weight, lower density component.

Abstract: It is an object of the present invention to provide a modified propylene resin containing very small amounts of low-crystalline and low-molecular-weight components. The present invention relates to a modified propylene resin characterized by satisfying the following requirements (1) to (4). (1) The melting point (Tm) measured with a differential scanning calorimeter (DSC) is 140° C. or higher. (2) The amount of grafts of ethylenic unsaturated bond-containing monomer after hot xylene washing is 0.1 to 5 percent by weight. (3) The amount of components soluble in o-dichlorobenzene at 70° C. is 1.5 percent by weight or less. (4) The intrinsic viscosity [?] is 0.1 to 4 dl/g.

Abstract: A terpolymer containing: a) from 90% to 50% by weight; preferably from 90% to 70% by weight of ethylene derived units; b) from 5% to 40% by weight; preferably from 5% to 20% by weight of derived units of alpha olefin of formula CH2?CHA wherein A is a C1-C20 alkyl radical; c) from 2% to 30% by weight, preferably from 5% to 20% by weight of cycloolefins derived units. Said terpolymer being characterized by the following features i) distribution of molecular weight Mw/Mn lower than 3.5; preferably lower than 3; more preferably lower than 2.7 ii) solubility in xylene at 25° C.

Abstract: An olefin/(meth)acrylate block copolymer in which a polyolefin segment obtained by polymerization of an olefin is covalently-bonded to a poly(meth)acrylate segment obtained by polymerization of a (meth)acrylate compound, and a morphology has a micro phase-separation structure.

Abstract: The present invention discloses a catalyst system consisting of a mono- or di-fluorinated metallocene catalyst component of formula and a fluorinated activating support.

Abstract: A bridged metallocene compound of formula (I) wherein: M is a transition metal; X, is a hydrogen atom, a halogen atom, or a hydrocarbon group optionally containing hetematoms; L is a divalent bridging group; R1 is a linear C1C40 hydrocarbon radical optionally containing hetexoatonis; T1, T2, T3 and T4 are an oxygen or sulfur atom or a C(R18)2 group with the proviso that at least one group between T1 and T2 is an oxygen or a sulfur atom; wherein R18, are hydrogen atoms or a C1-C4O hydrocarbon radical; n is 1, 2 or 3; R4 is a hydrogen atom or a C1-C40 hydro carbon radical; W is an aromatic 5 or 6 membered ring.

Abstract: A novel olefin-based polymer has excellent thermal resistance, as well as excellent balance among various properties. The olefin-based polymer is an olefin-based polymer comprising 50 to 100% by weight of a constituent unit derived from 4-methyl-1-pentene, and 0 to 50% by weight of a constituent unit derived from at least one olefin selected from olefins having 2 to 20 carbon atoms except 4-methyl-1-pentene, and having the following properties: i) the diad isotacticity is 70% or greater, ii) the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) as measured by gel permeation chromatography (GPC) is in the range of 1.0 to 3.5, and iii) the intrinsic viscosity [?] is 0.5 (dl/g) or greater.

Abstract: The present invention relates to the process for preparing hydrogenated nitrile rubber polymers having lower molecular weights and narrower molecular weight distributions than those known in the art.

Abstract: Disclosed are an ethylene polymerization process, a catalyst for use in the process, a production method employing the catalyst, and a product produced thereby. More specifically, disclosed is a process of producing an ethylene copolymer from ethylene and an alpha-olefin comonomer, in which the produced ethylene copolymer has a multimodal molecular weight distribution and excellent processability and physical properties, and thus can increase the value and productivity of products, including pipes and films. Particularly, the produced ethylene copolymer has a trimodal or higher molecular weight distribution or density distribution, and thus, when it is a linear low-density copolymer, it has an excellent effect of improving the impact strength of films, and when it is a medium-density ethylene copolymer, it can be produced into pipes, which have slow crack growth rate and can be used even at high temperature.

Abstract: The present invention relates to compositions and processes of making catalysts and polyolefins. More particularly, the invention relates to snap shut catalysts, processes for making the catalysts, processes for making polyolefins using the catalysts and the polyolefins resulting therefrom.

Abstract: A slurry process for polymerizing ethylene is disclosed. The process comprises polymerizing ethylene in a first reactor in the presence of hydrogen and a catalyst comprising an activator and a supported dimethylsilyl-bridged indeno[1,2-b]indolyl zirconium complex to produce an ethylene homopolymer, removing some of the unreacted hydrogen, and reacting the homopolymer slurry in a second reactor with ethylene and a C3-C10 ?-olefin to produce polyethylene. The polyethylene has weight-average molecular weight greater than 150,000, broad molecular weight distribution, low long-chain branching, and it provides pipes or molded articles with good environmental stress crack resistance.

Abstract: A process is disclosed for the preparation of zinc alkyl chain growth products via a catalysed chain growth reaction of an alpha-olefin on a zinc alkyl, wherein the chain growth catalyst system employs a group 3-10 transition metal, or a group 3 main group metal, or a lanthanide or actinide complex, and optionally a suitable activator. The products can be further converted into alpha-olefins by olefin displacement of the grown alkyls as alpha-olefins from the zinc alkyl chain growth product, or into primary alcohols, by oxidation of the resulting zinc alkyl chain growth product to form alkoxide compounds, followed by hydrolysis of the alkoxides.

Abstract: The present invention relates to a catalyst system, to a method of manufacturing this system, and also to uses of this system. The catalyst system of the invention is characterized in that it comprises molecules of a polymer having, at one of its ends or along the chain, one or more polar functional groups; a solvent, said solvent, due to the fact of said polar functional group of said polymer, provoking and maintaining, when said molecules of the polymer are introduced thereinto, an organization of said molecules of the polymer into aggregates, micelles or vesicles so that the polar functional groups of said polymer are located inside the aggregates, micelles or vesicles formed; and a catalyst activator and a catalyst trapped in said aggregates, micelles or vesicles of said polymer. The catalyst system of the present invention may be used, for example, for catalyzing a (co)polymerization of olefins.

Abstract: Provided is a transition metal compound novel and useful as a catalyst component for olefin polymerization, a catalyst for olefin polymerization containing the transition metal compound, and a process for producing an olefin polymer using the catalyst for polymerization. The transition metal is characterized by being represented by the following general formula [I]: wherein, R3 is hydrogen, R2 is selected from a hydrocarbon group or a silicon-containing group, R1 and R4 are selected from a hydrocarbon group having 2 to 20 carbon atoms and a silicon-containing group, each of R5, R6, R7, R8, R9, R10, R11, R12, R13 and R14, which is selected from hydrogen, a hydrocarbon group and a silicon-containing group, may be same or different from each other, and adjacent groups from R5 to R14 may be bonded to each other to form a ring.

Abstract: Norbornene monomers with fluorene group and polymer material thereof are disclosed. The norbornene monomers with fluorene group are prepared by Diels-Alder reation. The Norbornene monomers containing fluorene groups are highly active for ring-opening-metathesis polymerization (ROMP), and the molecular weight and PDI value of the obtained polymers are controllable.

Abstract: The present invention relates to an ethylene-alpha olefin copolymer comprising long chain branches (LCB), while having a narrow molecular weight distribution. The ethylene-alpha olefin copolymer can be prepared by a continuous solution polymerization process using an activated catalyst composition containing a Group 4 transition metal compound having a monocyclopentadienyl ligand, to which a quinoline amino group is introduced.

Abstract: Multinuclear catalyst complex comprising two or more active metal centres and at least one phenoxyimine compound and at least one substituted cyclopentadienyl, indenyl or fluorenyl derivative, each phenoxyimine compound being bonded to a cyclopentadienyl, indenyl or fluorenyl derivative forming a ligand framework, the cyclopentadienyl, indenyl or fluorenyl derivative being coordinated with one of the metal centres and the phenoxyimine compound being coordinated with an active metal centre other than the metal centre the cyclopentadienyl, indenyl or fluorenyl derivative is coordinated with, and wherein the phenoxyimine compound has the formula wherein R1 is hydrogen, alkyl, cycloalkyl, aryl or aralkyl; R2 is hydrogen, halogen, alkyl, cycloalkyl, aryl, O-alkyl or aralkyl; and R3 is alkyl, cycloalkyl, aryl or aralkyl, process for preparing a multinuclear catalyst composition comprising the steps of bonding a substituted phenoxyimine compound to a substituted cyclopentadienyl, indenyl or fluorenyl derivativ

Abstract: The present invention provides a polymerization process which is conducted by contacting an olefin monomer and at least one olefin comonomer in the presence of hydrogen and a metallocene-based catalyst composition. Polymers produced from the polymerization process are also provided, and these polymers have a reverse comonomer distribution, low levels of long chain branches, and a ratio of Mw/Mn from about 3 to about 6.

Abstract: A composite catalyst useful in the production of polyethylene, which comprises at least a first catalyst and a second catalyst separated by a polymer layer, with the first catalyst and the second catalyst being identical or different, is described. A composite catalyst useful in the production of polyethylene with a broad molecular weight distribution in a single polymerization reactor, which comprises at least a first catalyst and a second catalyst separated by a polymer layer, with the first catalyst and the second catalyst being different, is also described. A process for preparing said catalysts and a process for the production of a polyethylene by using said catalysts are also described.

Abstract: The present invention relates to process comprising reacting a polyfluorenes comprising at least one structural group of formula I with an iridium (III) compound of formula II wherein R1 and R2 are independently alkyl, substituted alkyl, aryl, substituted aryl or a combination thereof; R5is H or CHO; R3 and R4 are independently hydrogen, alkyl, substituted alkyl, aryl, substituted aryl or a combination thereof; R11 and R12 taken together form a substituted or unsubstituted monocyclic or bicyclic heteroaromatic ring; R13 is independently at each occurrence halo, nitro, hydroxy, amino, alkyl, aryl, arylalkyl, alkoxy, substituted alkoxy, substituted alkyl, substituted aryl, or substituted arylalkyl; Ar is aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a combination thereof; X is selected from a direct bond, alky, substituted alkyl, and combinations thereof; Y is CHO or NH2; Z is CHO or NH2 where Z does not equal Y; and p is 0, 1 or 2.

Abstract: The invention generally provides for methods for controlling polymer properties. In particular, invention provides for methods for controlling the comonomer composition distribution of polyolefins such as ethylene alpha-olefin copolymers by altering at least one or more of the following parameters: the molar ratio of hydrogen to ethylene, the molar ratio of comonomer to ethylene, the partial pressure of ethylene, and the reactor temperature without substantially changing the density and/or the melt index of the copolymer.

Abstract: Disclosed is a propylene block copolymer having excellent flexibility and impact resistance and showing a good polymer powder form. Also disclosed is a process for producing the copolymer. More specifically, the copolymer is a novel propylene block copolymer which satisfies a specific requirement and is produced by a process comprising continuously performing a multi-step polymerization composed of a former step in which a propylene homopolymer component or a specific propylene copolymer component is produced in the presence of a metallocene catalyst carried on a support and a latter step in which propylene and a specific copolymer component are produced by gas phase polymerization.

Abstract: A slurry process for polymerizing ethylene is disclosed. The process comprises polymerizing ethylene in the presence of an ?-olefin, hydrogen, and a catalyst comprising an activator and a supported, dimethylsilyl-bridged bis(indenoindolyl)zirconium complex. The process has high catalyst activity and produces polyethylene having a broad molecular weight distribution.

Abstract: The invention provides for a process to produce polymers utilizing a hydrofluorocarbon diluent.

Abstract: Aspects of the invention are directed to a process for producing polypropylene comprising: providing series reactors comprising a first and a second loop allowing flow of polypropylene, catalyst, hydrogen and propylene there between, wherein each loop comprises from six to eight legs, each leg having fluid connections there between; injecting into the first loop an amount of a catalyst, propylene and optionally hydrogen; withdrawing polypropylene, and unreacted propylene and optionally unreacted hydrogen from the first loop and injecting the polypropylene, and unreacted propylene and optionally unreacted hydrogen into the second loop; and providing a propylene/polypropylene separator fluidly connected to the second loop and isolating polypropylene therefrom. In one embodiment a recycle conduit is provided between the propylene/polypropylene separator and the second loop allowing the recycling of unreacted propylene and optionally hydrogen into the second loop.