Abstract: A catalyst system suitable for the polymerisation of olefins, said system comprising (a) a transition metal compound or lanthanide metal compound (b) a cocatalyst and (c) at least one porous support material characterised in that the porous support material has been pretreated with a halogen-containing organometallic compound, in particularly with a fluorine-containing organometallic compound. The catalyst system is particularly suitable for the preparation of polymers having broad molecular weight distributions from the polymerisation of olefins in the presence of a single site catalyst.

Abstract: Supported catalyst system for the polymerization of olefins, having at least two different monocyclopentadienyl transition metal compounds, one or more activators including an ionic compound having (i) a cation and (ii) an anion having up to 100 non-hydrogen atoms and the anion containing at least one substituent comprising a moiety having an active hydrogen, and one or more support materials. The supported “mixed or dual site” catalyst systems having different monocyclopentadienyl catalysts when activated by specific ionic activators lead to catalyst systems showing an improved balance of properties which may be used to prepare LLDPE polymers having broad melt flow ratios.

Abstract: Apparatus for mixing of a first gas and a second gas, including (i) a linear first tube for supply of the first gas, the first tube having an inlet for the first gas at an upstream end and tapering to form a nozzle at a downstream end, and (ii) a linear second tube for supply of the second gas. The second tube has an inlet for the second gas at an upstream end, a first portion which forms an annulus around the outer surface of the first tube upstream of the nozzle, and a second portion which forms a sheath around the nozzle of the first tube and which forms an area of expanded cross-section compared to the annulus.

Abstract: A process is disclosed for the preparation of zinc alkyl chain growth products via a catalyzed 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: Method for controlling a process for polymerising at least one olefin in a reaction zone, the process including in the reaction zone a reaction mixture and polymer particles, the reaction mixture containing a principal olefin and at least one further reagent. The method involves using the ratio of at least one further reagent to principal olefin in the polymer particles in the reaction zone or in the amorphous phase of the polymer particles.

Abstract: Method for transitioning from a first process for producing a first polymer to a second process for producing a second polymer. The first and second processes each include contacting a principal olefin and a comonomer with a catalyst under gas phase polymerization conditions to form the first or second polymer. The first and second processes utilize the same olefin but differ in at least one of the comonomer used and the reaction temperature at which the polymer is produced. The respective first or second polymer is then contacted with a purge gas to remove unreacted monomers. The method includes changing the flow rate of purge gas from a first rate to a second rate defined relative to a flow rate and temperature used for an earlier polymer produced using the same comonomer as the second process.

Abstract: Method for the preparation of a blown film containing 300-600 gels/m2 of size in the range 100-2000 ?m as measured by an optical control system, in which the film is derived by extrusion from an ethylene-?-olefin copolymer. The method is carried out by preparing the copolymer in a particle forming polymerization process in the presence of a single site catalyst system containing a single site catalyst, a cocatalyst, and a support material.

Abstract: The present invention relates to an apparatus and a process for polymerization, and, in particular, provides an apparatus for gas phase fluidised bed polymerization of olefins, which apparatus comprises: A) a first section which is an upright cylindrical section having a diameter, D1, and cross-sectional area, A1, and B) a second section, provided vertically above the first section and centered about a common vertical axis to the upright cylindrical first section, the base of the second section having a cylindrical cross-section of diameter D1 and being joined to the top of the first section, and the horizontal cross-sectional area of the second section above its base being greater than the cross-sectional area of the first section, characterized in that: i) D1 is greater than 4.5 meters, and ii) the second section has a maximum horizontal cross-sectional area, A2, which is between 3.2 and 6 times the cross-sectional area, A1, of the first section.

Abstract: Process for producing a degassed polymer powder, by a) feeding i) a principal monomer, and ii) one or more comonomers in an amount of at least 5000 ppmw relative to the principal monomer feed rate, and iii) optionally an added alkane having 2 to 10 carbon atoms, fed in an amount of at least 1000 ppmw relative to the principal monomer feed rate; into a polymerization reactor. The monomer and comonomers react to form a polymer including residual hydrocarbons having one or more hydrocarbons with 3 to 10 carbon atoms, and b) passing the polymer to a degassing step where it is contacted with a purge gas to remove some of the residual hydrocarbons.

Abstract: Process for polymerization of ethylene using a catalyst system including (i) a solid catalyst of Ti, Mg and halogen, (ii) a first activator which is at least one trialkylaluminium compound of the formula AlR3, where each R is independently a C2 to C20 alkyl radical, and (iii) a second activator which is at least one alkylaluminium chloride of the formula AlR?2Cl, where each R? is independently a C2 to C20 alkyl radical. The second activator is introduced directly into the polymerization reactor, without precontact with the solid catalyst, continuously or semi-continuously, and at a maximum rate of introduction at any time corresponding to less than 10 ppm by weight of chlorine relative to the rate of polyethylene production.

Abstract: Copolymer of ethylene and an alpha-olefin having (a) a density in the range 0.900-0.940 g/cm3, (b) a melt index MI2 (2.16 kg, 190° C.) in the range of 0.01-50 g/10 min, (c) a molecular weight distribution (Mw/Mn) in the range 3.5 to 4.5, and (d) a melt elastic modulus G?(G?=500 Pa) in the range 40 to 150 Pa. The copolymer has a melt index MI2 (2.16 kg, 190° C.) Dow Rheology Index (DRI) and melt elastic modulus G?(G?=500 Pa) satisfying the equations of [DRI/MI2]>0 and [DRI/MI2]<0.0225G??0.745.

Abstract: Process for devolatilization of a polymer of an aromatic alkylene, such as styrene and, in particular, an improved process using water as a stripping agent (i) in which the total amount of water to be disposed of can be reduced, (ii) which allows at least a portion of the water to be recycled as stripping agent, reducing make-up requirements for the stripping agent, and (iii) which allows at least a portion of the aromatic alkylene monomer in the water to be recycled to the polymerization process (via the devolatilization steps) rather than being disposed.

Abstract: Process for introducing a polymerisation catalyst in solid form into a gas-phase fluidised bed using an injection device having an inner tube of internal cross-sectional area of 10-100 mm2 and an outer tube forming an annulus around the inner tube with a cross-sectional area of 1-10 times the internal cross-sectional area of the inner tube. The polymerisation catalyst and a carrier gas are passed through the inner tube into the gas-phase fluidised bed at a carrier gas linear velocity of 4-14 m/s and a carrier gas mass flow rate of 10-35 kg/h. A shielding gas is passed through the outer tube and into the gas-phase fluidised bed at a shielding gas linear velocity of 1-10 times the linear velocity of the carrier gas through the inner tube and at a shielding gas mass flow rate of 100-500 kg/h. No cooled recycle process gas is provided to the injection device.

Abstract: Process for producing homopolymers or copolymers of conjugated dienes by contacting monomeric material having at least one conjugated diene with a catalyst system including two or more different transition metal compounds and optionally one or more activators. Preferred transition metal compounds are based on cobalt and chromium, especially complexes thereof having benzimidazole ligands.

Abstract: Process for controlling the (co)polymerization of olefins in a continuous polymerization reactor wherein the olefin (co)polymerization is performed in an industrial plant reactor in the presence of a polymerization catalyst characterized in that at least one operating parameter of the plant is controlled by means of a measurement of the chain branching level (CBL) of the produced polymer.

Abstract: Transition metal catalysts comprise (a) a source of a Group 3 to 10 transition metal, (b) a ligand having the formula: R1R2X—Y—XR3R4 wherein X is phosphorus, arsenic or antimony, Y is a bridging group having the formula: Z-(A)-D-Rm wherein Z is the moiety linking the X groups, A is a linear or cyclic hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl or substituted heterohydrocarbyl linking group wherein the number of atoms directly linking Z to D is 1, 2 or 3, D is N, P, As, O, S or Se, R is hydrogen, alkyl, hydrocarbyl, substituted hydrocarbyl, heteroalkyl, heterohydrocarbyl or substituted heterohydrocarbyl, and m is 1 or 2, R1, R2, R3, and R4 are the same or different and represent hydrocarbyl or functionalized hydrocarbyl moieties with the proviso that if D is nitrogen, R is not a cyclic ether, and optionally an activator. The transition metal catalysts are suitable for the selective trimerisation or tetramerisation of olefins in particular ethylene.

Abstract: A polymerization catalyst composition comprising (1) a transition metal compound of Formula (A), Z being 5-membered heterocyclic containing at least one carbon, at least one nitrogen and at least one of nitrogen, sulphur and oxygen, the others being nitrogen or carbon; M is a Group 3 to 11 metal or a lanthamide metal; E1 and E2 are divalent groups of aliphatic, alicyclic, aromatic or alkyl substituted aromatic hydrocarbon, or heterocyclic; D1 and D2 are donor atoms or groups; X is an anionic group, L is a neutral donor group; n=m=zero or 1; y and z are zero or integer such that X and L satisfy valency/oxidation state of M, (2) a catalyst-activating support which is a solid particulate substance, insoluble in hydrocarbons, comprising at least magnesium and aluminum atoms and hydrocarbyloxy groups containing 1 to 20 carbon atoms, the molar ration of Mg/Al being in the range 1.0 to 300 and the molar ratio of hydrocarbyloxy groups to aluminum atoms being in the range 0.5 to 2.

Abstract: The present invention relates to a method for reducing/suppressing sheeting or agglomerates during polymerisation of olefins, especially during the fluidised bed gas phase polymerisation of olefins. In particular, the present invention relates to a method for reducing/suppressing sheeting or agglomerates during the product grade transition and/or catalyst transitions occurring during polymerisation of olefins.

Abstract: A method for the preparation of copolymers of ethylene and ?-olefins having a fraction (%) of the molecular weight component of >1,000,000 of less than 6% comprises polymerising ethylene and an ?-olefin in the presence of a supported polymerisation catalyst system comprising (a) a transition metal compound (b) a porous support material, and (c) an activator characterized in that the support material has been (i) dried at a temperature in the range 0° C. to 195° C. in an inert atmosphere, and (ii) treated with an organometallic compound. The resultant supported catalyst systems show improved productivity and allow for control of the resultant polymer properties. Particularly preferred supported catalyst systems are those comprising metallocene complexes.

Abstract: The present invention relates to a process for contacting a hydrocarbon and an oxygen-containing gas with a catalyst bed in a reactor at a space velocity of at least 10,000 h?1, said process being characterised in that a) the reactor has a polygonal internal cross-section at least in the section where the catalyst bed is held, b) the catalyst bed is made up of 2 or more layers of catalyst in the form of tiles of polygonal shape, said tiles have at least 4 sides, c) each layer of catalyst comprises at least 4 tiles which tessellate together to form said layer, and d) the edges where 2 tiles meet in one layer do not align with the edges where 2 tiles meet in an adjacent layer.