摘要:
Olefin polymerization may be catalysed by a wide range of catalytic materials. Described herein is a heterogeneous olefin polymerization catalyst comprising a porous paniculate support material having impregnated therein a metallocene catalyst the metal atom whereof is bound to an amide group which is not bound to an &eegr;-ligand of the metallocene, or the reaction product of a said metallocene catalyst and a co-catalyst.
摘要:
Olefin polymerization comprising catalysts based on a metallocene, an alumoxane and a support are disclosed. The process for the preparation of a supported olefin ploymerization catalyst comprises: a) a metallocene/activator reaction product, a solvent capable of dissolving it, and a porous support are brought into mutual contact, and b) the solvent is removed, and wherein step a) is carried out so that the porous support is impregnated with a volume of the metallocene/activator reaction product and solvent, which does not exceed the total pore volume of the support.
摘要:
A process for the preparation of a heat sealable film comprising a core layer and a sealing layer, said process comprising attaching said core layer to said sealing layer, said sealing layer comprising an ethylene copolymer composition in which: (1) there are two distinct maxima in the TREF fractogram of the ethylene copolymer composition; (2) at lest 10%, of the ethylene copolymer composition elutes in TREF at a temperature of less than 50° C.; (3) at least 25%, of the ethylene copolymer composition elutes in TREF at a temperature of higher than 75° C.; (4) none of the ethylene copolymer composition elutes in TREF at a temperature of higher than 100° C.; (5) the ethylene copolymer composition comprises two components, one of which is of relatively high comonomer content and high molecular weight, the other of which is of relatively low comonomer content and low molecular weight, both components being prepared by polymerisation of ethylene with a C3-20 alpha-olefin in the present of a single site catalyst; (6) the ethylene copolymer composition has a density of between 905 and 930 kg/m3, and an MFR2 between 0.3 and 4.0 g/10 min.
摘要:
Aluminoxanes having C2-C10 alkyl groups can conveniently be used in supported olefin polymerization catalyst compositions prepared by contacting a support comprising a solid compound which is one of pure aluminium oxide, a mixed aluminium oxide, an aluminium salt, a magnesium halide, or a C1-C8 alkoxy magnesium halide, in any order with at least a) an organometallic compound, b) a metallocene, and c) an aluminoxane, and recovering said supported olefin polymerization catalyst composition.
摘要:
A method for transitioning between two different catalysts in olefin polymerizations, a first catalyst and a second catalyst, comprising the steps of: discontinuing the feed of the first catalyst into the polymerization reactor, and introducing the second catalyst into the reactor, wherein the transition is performed between a chromium-based catalyst and a metallocene catalyst.
摘要:
Process for the preparation of a solid catalyst system (CS) comprising the steps of preparing a liquid clathrate (LC) comprising (a) a lattice (L) being the reaction product of (i) aluminoxane (A), (ii) an organometallic compound (O) of a transition metal (M) of Group 3 to 10 of the Periodic Table (IUPAC 2007) or of an actinide or lanthanide, and (i) a compound (B) being effective to form with the aluminoxane (A) and the organometallic compound (O) the lattice (L), and (b) a guest (G) being an hydrocarbon compound (HC), and subsequently precipitating said liquid clathrate (LC) obtaining said solid catalyst system (SC).
摘要:
A process is disclosed for producing a multi-modal linear low density polyethylene in at least two staged reactors connected in series, comprising (i) polymerizing in a first slurry phase stage ethylene monomers with a Ziegler-Natta polymerization catalyst system to obtain a first polyethylene fraction component (A); and (ii) polymerizing in a second gas or slurry phase stage ethylene monomers with a Ziegler-Natta polymerization catalyst system to obtain a second polyethylene fraction component (B). The Ziegler-Natta polymerization catalyst system comprises: 1) a solid procatalyst formed by contacting at least: a) a Mg-alcoholate complex of formula (I) b) an aluminum compound of formula (II); and c) a vanadium compound and a titanium compound having a molar ratio (V:Ti) from 10:90 to 90:10; and 2) one or more organometallic cocatalvsts of formula (III). The linear low density polyethylene shows an improved comonomer composition distribution Formulas (I), (II), and (III) are described herein.
摘要:
The invention relates to metallocene compounds having the formula (I): (CpYq)mMRnBo (I) wherein: Cp or each same or different Cp is a non-substituted or substituted, fused or non-fused, homo(iso)cyclic or heterocyclic cyclopentadienyl ligand, indenyl ligand, tetrahydroindenyl ligand, fluorenyl ligand or octahydrofluorenyl ligand, Y or each same or different Y is a substituent at the cyclopentadienyl ring of said ligand Cp having the following structure (II): wherein: D is an element of Group 14 of the Periodic Table (IUPAC), R1, R2 and R3 are the same or different and are each one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, or at least two of R1, R2 and R3 form together with D a C4-C20 ring structure; M is a transition metal of Group 4 of the Periodic Table (IUPAC) and is bound to the ligand Cp or ligands Cp in an &eegr;5 bonding mode; R or each same or different R is bound to M and is one of a hydrogen, a halogen, a substituted or unsubstituted C1-C10 hydrocarbyl group, a substituted or unsubstituted C1-C10 hydrocarbyloxy group, a C1-C12 organosilicon group, or two R form together with M a C4-C20 metallocyclic ring structure; B is a bridge atom or group between two Cp ligands or between one Cp ligand and M; q is, when Cp is non-bridged, 0-5 for the cyclopentadienyl ligand, 0-3 for the indenyl or tetrahydroindenyl ligand and 0-1 for the fluorenyl or octahydrofluorenyl ligand, q is, when Cp is bridged, 0-4 for the cyclopentadienyl ligand, 0-2 for the indenyl or tetrahydroindenyl ligand and 0 for the fluorenyl or octahydrofluorenyl ligand; m is 1 or 2; m·q≧1; o is 0 or 1; and n is 4-m-o, except when there is one bridge B between two Cp ligands, in which case n is 4-m, their intermediates, preparation and use.
摘要:
A process for the polymerisation of ethylene and optionally at least one C3-20 alpha olefin comonomer in the slurry or solution phase in a reactor having a polymer outlet stream, a procatalyst or catalyst feed stream and a hydrogen feed stream, said polymerisation being effected in the presence of a metallocene catalyst, a diluent and hydrogen, wherein said diluent is recycled from said outlet stream to said hydrogen feed stream, said procatalyst or catalyst feed stream is free of hydrogen, said hydrogen feed stream is free of procatalyst or catalyst and said procatalyst or catalyst feed stream does not comprise recycled diluent.
摘要:
A process for the polymerisation of ethylene and optionally at least one C3-20 alpha olefin comonomer in the slurry or solution phase in a reactor having a polymer outlet stream, a procatalyst or catalyst feed stream and a hydrogen feed stream, said polymerisation being effected in the presence of a metallocene catalyst, a diluent and hydrogen, wherein said diluent is recycled from said outlet stream to said hydrogen feed stream, said procatalyst or catalyst feed stream is free of hydrogen, said hydrogen feed stream is free of procatalyst or catalyst and said procatalyst or catalyst feed stream does not comprise recycled diluent.