Abstract: The present invention relates to a process for the continuous transition between two different and compatible polymerisation catalysts.

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: Use of a metallocene compound of general formula Ind2R?MQ2 as a component of a catalyst system in producing polyethylene, wherein each Ind is the same or different and is indenyl or substituted indenyl; R? is a bridge which comprises a C1 to C4 alkylene radical, a dialkyl germanium or silicon or siloxane, alkyl phosphine or amine, which bridge is substituted or unsubstituted, M is a Group IV metal or vanadium and each Q is hydrocarbyl having 1 to 20 carbon atoms or halogen; and the ratio of meso to racemic forms of the metallocene in the catalyst system is at least 1:3. The metallocene may be supported. The ethylene may be polymerized in a reaction medium that is substantially free of any external comonomer, with comonomer being formed in situ. The produced polyethylene may have long chain branching. The produced polyethylene may be atactic.

Abstract: A propylene/ethylene/1-hexene terpolymer containing from 1.0 wt% to 2.5 wt %, of ethylene derived units and from 2.0 wt % to 4.0 wt % of 1-hexene derived units, the sum of the amounts of propylene, ethylene and 1-.hexene derived units being 100, having the following features: a) the amount (Wt %) of 1-hexene (C6) and the amount (Wt %) of ethylene (C2) fulfil the following relation: C2<?0.18C6+2.86; b) Polydispersity index (PI) ranging from 2 to 10; c) melting temperature ranging from 125° C., to 139° C.; d) solubility in xylene at 25° C. below 10 wt %; e) melt index (MFR) of from 4 to 6 g/10? dg/min, according to ISO method 1133; and f) crystallization temperature ranging from 85° C. to 100° C.

Abstract: An ethylene-?-olefin copolymer, wherein the ethylene-?-olefin copolymer has a density of 860 to 950 kg/m3 and a melt flow rate of 0.01 to 100 g/10 min, wherein in a molecular weight curve measured by gel permeation chromatography, the molecular weight of the copolymer providing the highest peak exists within the range of 10,000 to 20,000, wherein the height of the peak at a molecular weight of 177,000 is 5 to 30% where the height of the highest peak is 100%, wherein a characteristic relaxation time of the copolymer satisfies a relation represented by formula (1), and wherein the ethylene-?-olefin copolymer exhibits more than one melt peak observed by a differential scanning calorimeter. 40.2×MFR?0.606<?<71.8×MFR?0.

Abstract: This invention is related to the field of olefin polymerisation in double loop reactors and especially to the polymerisation of olefins with very active catalyst systems. It discloses a method for reducing blockage when transferring polymer product from the first loop to the second loop of a double loop reactor.

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: Olefin polymer with narrow molecular weight distribution and specific molecular weight, olefin polymer having functional group introduced at terminal, tapered polymer containing segment wherein monomer composition continuously changes in the polymer chain, olefin polymer having different segments bonded to each other, and process for preparing these polymers. The olefin polymers are polymers of C2-20 carbon atom olefins and have a number-average molecular weight of ?500 and Mw/Mn of ?1.5. In syntheses, an olefin of 2-20 carbon atoms is polymerized in the presence of a catalyst comprising a transition metal compound represented by the formula LmMXn wherein M is a transition metal atom of Group 3-11, m is 1-5, n is a number satisfying a valence of M, L is a ligand—coordinated to the central metal M—which contains a heteroatom having no direct bond to the central metal, and X is e.g. halogen or a hydrocarbon.

Abstract: Provided are ethylene copolymers with excellent impact resistance. More specifically, provided are ethylene copolymers satisfying certain correlation between the falling dart impact strength (F) or high rate impact resistant breakage energy (E) and Vicat softening point. The ethylene copolymers with improved impact properties are applicable to film, injection, compound, sheet, roto, pipe or blow molding.

Abstract: A material for vibration control of the invention includes a propylene polymer (A) containing a constitutional unit (a) derived from propylene in the proportion of 40 to 100 mol % and a constitutional unit (b) derived from ?-olefin having 2 to 20 carbon atoms excluding propylene in the proportion of 60 to 0 mol % [provided that the total of (a) and (b) is 100 mol %], and having a melting point measured by DSC of 90° C. or below or no observed melting point, and the material has excellent vibration controllability such as vibration damping property, vibration preventing property, sound insulating property, and sound absorbing property.

Abstract: The invention relates to the field of producing polymers and copolymers of olefin oligomers produced by a trimerization reaction of olefin monomers. There is disclosed a process which comprises producing olefin oligomers with the aid of a trimerization catalyst system prepared using UHF irradiation for activating individual components of the trimerization catalyst system. The use of the trimerization catalyst system thus improved and having increased activity provides for increased effectiveness in the production of olefin oligomers from ethylene or other olefin monomers, inter alia, at a low pressure of ethylene. The olefin oligomers thus produced are then polymerized or copolymerized using processes known in the art. The technical effect consists in increasing the effectiveness of the production of olefin oligomers which are then used in a polymerization or copolymerization reaction.

Abstract: Catalyst compositions comprising a first metallocene compound, a second metallocene compound, an activator-support, and an organoaluminum compound are provided. An improved method for preparing cyclopentadienyl complexes used to produce polyolefins is also provided.

Abstract: A polymer having a density of from about 0.960 g/cc to about 0.965 g/cc and a melt index of from about 0.2 g/10 min. to about 0.6 g/10 min. wherein an article formed from the polymer has an environmental stress crack resistance of equal to or greater than about 150 hours when measured in accordance with ASTM D 1693 condition B, 100% Igepal. A polymer having a density of from about 0.955 g/cc to about 0.960 g/cc and a melt index of from about 0.2 g/10 min. to about 0.6 g/10 min. wherein an article formed from the polymer has an environmental stress crack resistance of equal to or greater than about 500 hours when measured in accordance with ASTM D 1693 condition B, 100% Igepal.

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: The present invention relates to a process for the gas phase polymerisation of olefins, and, in particular, to a process for the gas phase polymerisation of olefins with recycle of fines to the reaction zone.

Abstract: Copolymers of ethylene and ?-olefins are provided having (a) a density (D) 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 melt index MI2 (2.16 kg, 190° C.) and Dow Rheology Index (DRI) satisfying the equation [DRI/MI2]>2.65, and (d) a Dart Drop Impact (DDI) in g of a blown film having a thickness of 25 ?m produced from the copolymer satisfying the equation DDI?1900×{1?Exp[?750(D?0.908)2]}×{Exp[(0.919?D)/0.0045]}. The copolymers may suitably be prepared by use of metallocene catalysis and are preferably prepared in multistage processes earned out in loop reactors in the slurry phase. The copolymers exhibit long chain branching as defined by Dow Rheology Index (DRI) and exhibit unexpected improvements in mechanical properties, in particular dart drop impact, when extruded into blown films.

Abstract: A method comprising contacting an olefin in the presence of a catalyst and a melt index modifier (MIM) under conditions suitable to form a polyolefin and recovering the polyolefin, wherein the polyolefin melt index is increased by at least about 25%, wherein the normalized catalyst activity is decreased by less than about 10%, and wherein the MIM is characterized by the general formula R1—HC?CH—R2 or R3R4C?CH2 where R1, R2, R3, R4 are each selected from the group consisting of a non-aromatic organyl group.

Abstract: This invention relates to a polymacromonomer comprising at least one macromonomer and from 0 to 20 wt % of a C2 to C12 comonomer, wherein the macromonomer has vinyl termination of at least 70%, and wherein the polymacromonomer has: a) a g value of less than 0.6, b) an Mw of greater than 30,000 g/mol, c) an Mn of greater than 20,000 g/mol, d) a branching index (g?)vis of less than 0.5, e) less than 25% vinyl terminations, f) at least 70 wt % macromonomer, based upon the weight of the polymacromonomer, g) from 0 to 20 wt % aromatic containing monomer, based upon the weight of the polymacromonomer and h) optionally, a melting point of 50° C. or more. This invention also relates to processes to make such polymacromonomers.

Abstract: In some embodiments, a method including the steps of monitoring a polymerization reaction which produces a polymer resin in a fluid bed reactor, where a dry melt reference temperature is characteristic of melting behavior of a dry version of the resin, and in response to data indicative of at least one monitored parameter of the reaction, determining in on-line fashion a reduced melt reference temperature that is at least substantially equal to the difference between the dry melt reference temperature and a temperature by which the dry melt reference temperature is depressed by the presence of condensable diluent gas with the resin in the reactor. Optionally, the method also includes the step of controlling the reaction in response to the reduced melt reference temperature or a stickiness parameter determined from the reduced melt reference temperature.

Abstract: A highly active supported chromium catalyst composition for ethylene and other olefins polymerization and also for ethylene copolymerization with efficient incorporation of comonomer, produces polymers with superior spherical morphology, improved bulk density and almost 0% fines. The catalyst composition component includes at least one chromium compound, mainly chromium acetylacetonate, or chromium hexaflouroacetonylacetonate, or chromium diethylmalonate. One magnesium compound, or aluminum compound, metal alkoxy compound and defined polymer particles mainly chloromethylated cross linked styrene-DVB copolymer or polyvinylchloride. The catalyst composition, when used in conjunction with an organoaluminum compound or a mixture of organoaluminum compounds, can be used for olefin polymerization to produce medium or high density polyethylene and copolymers of ethylene with alpha-olefins having about 3 to 18 carbon atoms.

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: A polyolefin has 1) a density in the range of 0.93 to 0.97 g/cm3, 2) a BOCD (Broad Orthogonal Co-monomer Distribution) index defined by a given equation in the range of 1 to 5, and 3) a molecular weight distribution (weight average molecular weight/number average molecular weight) in the range of 4 to 10. A supported hybrid metallocene catalyst comprises a first metallocene compound represented by a first given formulae, a second metallocene compound represented by one of three given formulae, and a support.

Abstract: The present invention relates to catalyst systems containing solid catalyst components comprising titanium, magnesium, halogen and a 1,8-naphthyl diaryloate internal electron donor compound; organoaluminum compounds and alkyl benzoate derivatives as external electron donors. The present invention also relates to methods of making the catalyst systems, and methods of polymerizing or copolymerizing alpha-olefins using the catalyst systems.

Abstract: The present invention relates to polymer blends comprising: (a) from 5 wt % to 95 wt % of a HDPE having a density from 0.941 g/cm3 to 0.980 g/cm3 and an I22 of 10 dg/min or more; and (b) from 95 wt % to 5 wt % of a grafted mPE, which is a reaction product of (i) a mPE having a density from 0.860 g/cm3 to 0.935 g/cm3 and an I2 from 0.7 dg/min to 5.0 dg/min, and (ii) a silicon-containing grafting component, wherein the blend exhibits a high-temperature creep after extrusion that is at least 20% lower than a blend of the HDPE and the mPE that has not been grafted with a silicon-containing grafting component. These blends can advantageously comprise at least one layer of a film, e.g., made via extrusion.

Abstract: Mono-oriented film having a shrink rate at 100° C. of at least 15% and at least one layer of which comprises a propylene copolymer with ethylene and optionally other olefins of formula CH2?CHR in which R is an alkyl group containing from 2 to 10 carbon atoms, having at least 5.5% wt of ethylene, a melt flow rate according to ISO 1133 (230° C., 2.16 Kg) of less than 10, and a fraction of polymer soluble in xylene at 25° C. ranging from 14 to 30% weight based on the total weight of said copolymer. The said films are particularly suited for the manufacturing of shrink labels.

Abstract: A novel polyethylene is devised which polyethylene is particularyl advantageous for manufacturing rotomoulded articles.

Abstract: A novel polyethylene is devised which polyethylene is particularly advantageous for manufacturing rotomoulded articles.

Abstract: The instant invention provides rotational molded articles, and method of making the same. The rotational molded articles according to the present invention comprise a polyethylene composition comprising: (a) at least 85 percent by weight of the units derived from ethylene; and (b) less than 15 percent by weight of units derived from one or more ?-olefin comonomers; wherein the polyethylene composition has a density in the range of 0.930 to 0.945 g/cm3, a molecular weight distribution (Mw/Mn) in the range of 1.70 to 3.50, a melt index (I2) in the range of 0.5 to 20 g/10 minutes, a molecular weight distribution (Mz/Mw) in the range of less than 2.5, vinyl unsaturation of less than 0.06 vinyls per one thousand carbon atoms present in the backbone of the polyethylene composition.

Abstract: The invention is directed to a use of a polymer composition comprising an ethylene polymer for producing a crosslinked pipe, a process for producing a crosslinked pipe and to a crosslinked pipe comprising a crosslinked polymer composition which comprises a crosslinked ethylene polymer.

Abstract: The present invention relates to polymer compositions comprising a grafted and at least partially crosslinked mLLDPE that is the reaction product of: (i) a mLLDPE having a density from 0.910 g/cm3 to less than 0.940 g/cm3 and an I2 from 0.7 dg/min to 5.0 dg/min; (ii) a silicon-containing grafting component; and (iii) a crosslinking agent, wherein the composition exhibits a die shrinkage upon extrusion that is at least 10% lower than the composition, prior to grafting and crosslinking of the mLLDPE. These compositions can optionally be blended with HDPE. The compositions can also comprise at least one layer of a film, e.g., made via extrusion.

Abstract: This invention relates to a process for polymerizing olefins in which the amount of trimethylaluminum in a methylalumoxane solution is adjusted to be from 1 to 25 mol %, prior to use as an activator, where the mol % trimethylaluminum is determined by 1H NMR of the solution prior to combination with any support. This invention also relates to a process for polymerizing olefins in which the amount of an unknown species present in a methylalumoxane solution is adjusted to be from 0.10 to 0.65 integration units prior to use as an activator, where the amount of the unknown species is determined by the 1H NMR spectra of the solution performed prior to combination with any support. Preferably, the methylalumoxane solution is present in a catalyst system also comprising a metallocene transition metal compound.

Abstract: Provided is an ethylene copolymer having improved hygienic property. More particularly, the ethylene copolymer satisfies a correlation between a density thereof and an extract content. The ethylene copolymer having improved hygienic property can be applied in injection molding, rotation molding, or blow molding.

Abstract: The present invention provides an ethylene polymer that has excellent fluidity and moldability as well as gives a molded product having excellent mechanical strength. The ethylene polymer of the present invention contains 0.02 to 1.50 mol % of a constitutional unit derived from ?-olefin having 6 to 10 carbon atoms, and has the density of 945 to 975 kg/m3, which satisfies both of the following requirements [1] and [2] simultaneously: [1] in CFC, all the components having a molecular weight of 100,000 or more are eluted at a temperature of 85° C. or higher; and [2] the components eluted at a temperature of 80° C. or lower account for up to 5% of all the components eluted in CFC.

Abstract: Embodiments of the invention provide a class of mesophase separated ethylene/?-olefin block interpolymers with controlled block sequences. The ethylene/?-olefin interpolymers are characterized by an average block index, ABI, which is greater than zero and up to about 1.0 and a molecular weight distribution, Mw/Mn, greater than about 1.4. Preferably, the block index is from about 0.2 to about 1. In addition or alternatively, the block ethylene/?-olefin interpolymer is characterized by having at least one fraction obtained by Temperature Rising Elution Fractionation (‘TREF’), wherein the fraction has a block index greater than about 0.3 and up to about 1.0 and the ethylene/?-olefin interpolymer has a molecular weight distribution, Mw/Mn, greater than about 1.4.

Abstract: A fiber is obtainable from or comprises a blend of a propylene based polymer and an ethylene/?-olefin interpolymer characterized by an elastic recovery, Re, in percent at 300 percent strain and 1 cycle and a density, d, in grams/cubic centimeter, wherein the elastic recovery and the density satisfy the following relationship: Re>1481?1629(d). Such interpolymer can also be characterized by other properties. The fibers made therefrom have a relatively high elastic recovery and a relatively low coefficient of friction. The fibers can be cross-linked, if desired. Woven, knitted or non-woven fabrics can be made from such fibers.

Abstract: A process for the production of an ethylene alpha-olefin copolymer is disclosed, the process including polymerizing ethylene and at least one alpha-olefin by contacting the ethylene and the at least one alpha-olefin with a metallocene catalyst in at least one gas phase reactor at a reactor pressure of from 0.7 to 70 bar and a reactor temperature of from 20° C. to 150° C. to form an ethylene alpha-olefin copolymer. The resulting ethylene alpha-olefin copolymer may have a density D of 0.927 g/cc or less, a melt index (I2) of from 0.1 to 100 dg/min, a MWD of from 1.5 to 5.0. The resulting ethylene alpha-olefin copolymer may also have a peak melting temperature Tmax second melt satisfying the following relation: Tmax second melt>D*398?245.

Abstract: A fiber is obtainable from or comprises an ethylene/?-olefin interpolymer characterized by an elastic recovery, Re, in percent at 300 percent strain and 1 cycle and a density, d, in grams/cubic centimeter, wherein the elastic recovery and the density satisfy the following relationship: Re>1481?1629(d). Such interpolymer can also be characterized by other properties. The fibers made therefrom have a relatively high elastic recovery and a relatively low coefficient of friction. The fibers can be cross-linked, if desired. Woven or non-woven fabrics can be made from such fibers.

Abstract: The invention provides a thermoplastic resin composition including a thermoplastic resin component (I) in an amount of 100 parts by mass, and a filler (II) in an amount of 1 to 900 parts by mass, wherein the thermoplastic resin component (I) contains a block copolymer (A) in an amount of 5 to 90 mass %, the block copolymer (A) being at least one species selected from among a block copolymer and a hydrogenated product thereof, the block copolymer having a polymer block (a1) formed mainly of an aromatic vinyl compound unit(s), and a polymer block (a2) formed mainly of a conjugated diene unit(s); a polyolefin resin (B) in an amount of 5 to 90 mass %; and a block copolymer (C) in an amount of 5 to 90 mass %, the block copolymer (C) having a polymer block formed from a repeating unit having a polar group.

Abstract: Method of polymerizing ethylene with C3-C20-olefine-comonomer, comprising the step of carrying out the olymerization in a single gas phase reactor with a mixed catalyst system herein the catalyst system has a catalyst mileage of higher than 6000 g polymer product/g catalyst.

Abstract: A novel PE material is devised showing excellent mechanical/optical properties and process ability, e.g. for film extrusion. The polyethylene of the invention is produced in one single e.g. gas phase reactor.

Abstract: Disclosed herein is a polymer composition, its manufacture and use, said composition may comprise greater than about 90 mole % propylene monomer, and having a unique combination of properties, including one or more of the following: a heat of fusion of more than about 108 J/g, a melting point of 165° C. or higher, a Melt Flow Rate so low that it is essentially not measurable and a molecular weight of greater than about 1.5×106. Further disclosed herein are blends or mixtures of the present novel polymer composition and products, such as, for example, microporous film structures and the like comprising same.

Abstract: A polyethylene which comprises ethylene homopolymers and/or copolymers of ethylene with 1-alkenes and has a molar mass distribution width Mw/Mn of from 5 to 30, a density of from 0.92 to 0.955 g/cm3, a weight average molar mass Mw of from 50000 g/mol to 500 000 g/mol and has from 0.01 to 20 branches/1000 carbon atoms and a z-average molar mass Mz of less than 1 million g/mol, a process for its preparation, catalysts suitable for its preparation and also films in which this polyethylene is present.

Abstract: Ethylene copolymers composed of ethylene units and units composed of at least one other 1-olefin whose density is from 0.940 to 0.955 g/cm3, whose vinyl end group content is at least 0.5 end groups, based on 1000 carbon atoms, whose tensile impact strength atn, measured to ISO 8256 (1997)/1A at ?30° C., is greater than or equal to 145 kJ/m2, and whose content of comonomer side chains per 1000 carbon atoms Cx is above a value defined via equation I, Cx=128.7?134.62 d? (I), where d? is the density d of the copolymer in g/cm3, and a process for their preparation, and their use as blow-molded products.

Abstract: Disclosed is a homogeneous catalyst system for producing an ethylene homopolymer or an ethylene copolymer with ?-olefin. Specifically, this invention pertains to a transition metal catalyst which has stability under high temperature solution polymerization at 120˜250° C., in which a cyclopentadiene derivative and an electron donating substituent, both of which are bonded to a Group IV transition metal acting as a central metal, are crosslinked through a silyl derivative substituted with a cyclohexyl, to a catalyst system including such a transition metal catalyst and an aluminoxane cocatalyst or a boron compound cocatalyst, and to a method of producing an ethylene homopolymer or an ethylene copolymer with ?-olefin, having high molecular weight, using the catalyst system under conditions of high-temperature solution polymerization.

Abstract: The present invention provides a process for the production of a degassed polymer powder, which process comprises a) feeding i) a principal monomer, and ii) one or more comonomers fed in an amount of at least 5000 ppmw relative to the principal monomer feed rate, and iii) optionally one or more added alkanes having 2 to 10 carbon atoms, fed in an amount of at least 1000 ppmw relative to the principal monomer feed rate; into a polymerisation reactor wherein the monomer and comonomers react to form a polymer comprising residual hydrocarbons comprising one or more hydrocarbons having 3 to 10 carbon atoms, and b) passing the polymer to a degassing step wherein it is contacted with a purge gas to remove at least some of the residual hydrocarbons, characterised in that: 1) the G/P ratio in the degassing step is higher than a minimum G/P ratio, G being the purge gas mass flow rate in the degassing step and P being the polymer throughput of the degassing step, and 2) the purge gas has a concentration of critical hydr

Abstract: The present invention relates to a process for polymerisation, and, in particular, to a process for start-up of a gas phase fluidised bed polymerisation reaction, said reaction comprising polymerisation of one or more monomers using a catalyst in a reactor, and said process comprising: a) providing a start-up bed of particles in the reactor in the presence of the one or more monomers but in the absence of the catalyst, b) introducing catalyst to the reactor to initiate reaction and start-up polymer production, said introduction being designated as time T0, c) at a time Ti, Ti being between 1 and 6 hours after T0, the value of Xi is less than a threshold value, wherein: Xi=Cumulative production in the time period T0 to Ti (Cumulative catalyst injection the time period T0 to Ti*PiC2=), PiC2= being the ethylene partial pressure in the reactor at the time Ti, d) subsequently stopping the injection of catalyst, e) taking a corrective action to address the low value of Xi.

Abstract: Copolymers of ethylene and an alpha-olefin having (a) a density in the range 0.900-0.940 g/cm3, (b) a molecular weight distribution (Mw/Mn) in the range 3.5 to 4.5, (c) a melt elastic modulus G? (G?=500 Pa) in the range 40 to 150 Pa, (d) an activation energy of flow (Ea) in the range 28-45 kJ/mol, and (e) a melt index (g/10 ml) in the range 1.0-3.5. The copolymers are suitably prepared in the gas phase by use of a supported metallocene catalyst system. The copolymers show improved processability and are particular suitable for use in blown film applications.

Abstract: The present invention relates to a method for controlling a process for polymerisation of an olefin, and in particular to a method for controlling a process for polymerising at least one olefin in a reaction zone, said process comprising in the reaction zone a reaction mixture and polymer particles, the reaction mixture comprising a principal olefin and at least one further reagent, and wherein the process is controlled 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 said polymer particles.

Abstract: Embodiments of the invention provide a class of ethylene/?-olefin block interpolymers. The ethylene/?-olefin interpolymers are characterized by an average block index, ABI, which is greater than zero and up to about 1.0 and a molecular weight distribution, Mw/Mn, greater than about 1.3. Preferably, the block index is from about 0.2 to about 1. In addition or alternatively, the block ethylene/?-olefin interpolymer is characterized by having at least one fraction obtained by Temperature Rising Elution Fractionation (‘TREF’), wherein the fraction has a block index greater than about 0.3 and up to about 1.0 and the ethylene/?-olefin interpolymer has a molecular weight distribution, Mw/Mn, greater than about 1.4.

Abstract: Embodiments of the present invention relate to operating a gas-phase reactor at or near maximum production rates and to measuring and controlling polymer stickiness in a gas phase reactor polymerization. In particular, embodiments relate to monitoring acoustic emissions in a reactor during gas phase polymerization to determine the onset of reactor stickiness and possibly discontinuity events such as chunking and sheeting resulting from that stickiness. Embodiments also relate to monitoring acoustic emissions to determine the need for effective control of parameters that minimize reactor stickiness and thereby preventing discontinuity events. The emissions are processed by arithmetic averaging.