Abstract: An optically clear thermoplastic resin composition is disclosed which comprises structural units derived from substituted or unsubstituted polycarbonate and substituted or unsubstituted polyester, wherein said polyester comprises structural units derived from terephthalic acid and a mixture of 1,4-cyclohexane dimethanol and ethylene glycol, wherein said ethylene glycol is greater than about 60 mole percent based on total moles of 1,4-cyclohexane dimethanol and ethylene glycol. In addition the composition disclosed possess good environmental stress cracking resistance, flow and thermal properties.

Abstract: Disclosed herein is a multimodal polymer composition comprising 45 to 75 wt % of a first polymer fraction, 25 to 55 wt % of a second polymer fraction, and from 10-50 phr of an extender oil. The multimodal polymer composition has an overall Mooney viscosity of less than 90 ML(1+4@125° C.), and each polymer fraction comprises an ethylene, C3-C10 alpha-olefin, non-conjugated diene polymer, wherein the first polymer fraction has a Mooney viscosity of greater than or equal to about 150 ML(1+4@125° C.), the second polymer fraction has a Mooney viscosity from about 20 to about 120 ML(1+4@125° C.). A process for making the multimodal polymer composition comprising a process utilizing two or more reactors in series is also disclosed.

Abstract: Disclosed is a mass polymerized rubber-modified monovinylidene aromatic copolymer composition with an excellent balance of physical and mechanical properties especially low temperature impact, and methods for preparing such a composition.

Abstract: Process in continuous carried out in the presence of at least two reactors in series, for the preparation of statistical vinyl arene/conjugated diene copolymers, the vinyl arene content ranging from 15 to 50% by weight, by means of the copolymerization under isothermal conditions in a hydrocarbon solvent, at a temperature ranging from 30 to 120° C., of vinyl arene/conjugated diene monomers, in the presence of at least one initiator and a 2-methoxy ethyl tetra-hydrofuran (THFA-ethyl) modifier.

Abstract: In a process for producing a polymer blend, at least one first monomer is polymerized in a first slurry phase reaction zone in the presence of a supported first catalyst to produce a thermoplastic first polymer having a crystallinity of at least 30%. At least part of said first polymer is then contacted with at least one second monomer different from said first monomer in a second solution phase reaction zone in the presence of a second catalyst and in the absence of polyenes under conditions to produce a second polymer having a crystallinity of less than 20%.

Abstract: A film of a polyethylene produced by polymerization catalysed by a single site catalyst and comprising as comonomers to ethylene at least two C4-12 alpha olefins, preferably but-1-ene and hex-1-ene.

Abstract: The present invention relates to a polyethylene resin having a multimodal molecular weight distribution, said resin being further characterized in that it has a density in the range of from about 0.925 g/ccm to about 0.950 g/ccm, a melt index (I2) in the range of from about 0.05 g/10 min to about 5 g/10 min, and in that it comprises at least one high molecular weight (HMW) ethylene interpolymer and at least a low molecular weight (LMW) ethylene polymer, and a composition comprising such resin. Also provided is a shaped article comprising said resin or composition, in particular a pipe.

Abstract: Embodiments of the present invention include a polypropylene homopolymer synthesized from a metallocene catalyst system and methods of forming the homopolymer, the homopolymer having an aluminum and chlorine recoverables value of less than 25 ppm and a xylene solubles of less than 1 wt % relative to the total weight of the homopolymer. The resulting homopolymer has other desirable properties such as a heat deflection temperature at 0.45 MPa of from 90° C. to 110° C., and a MWD value of from 1.7 to 5.0. These properties make embodiments of the homopolymer desirable for films, and in particular for capacitor films.

Abstract: An ethylene polymer composition having a density of at least 950 kg/m3, a fluidity index MI5 of 0.05 to 2 g/10 min and a content of alpha-olefin containing from 4 to 10 carbon atoms of from 0.15 to 1 mole %, containing from 53 to 63% by weight based on the total weight of the composition of an ethylene polymer fraction (A) having a fluidity index MI2 of at least 100 g/10 min a density of at least 969 kg/m3 and a molecular weight distribution Mw/Mn greater than 4, and from 37 to 47% by weight based on the total weight of the composition of a copolymer fraction (B) of ethylene and from 0.32 to 2.7 mole % of at least one alpha-olefin containing from 4 to 10 carbon atoms, a fluidity index MI5 to 0.001 to 0.5 g/10 min, a density of no more than 930 kg/m3 and a molecular weight distribution Mw/Mn greater than 4, wherein the ratio of the MI2 of fraction (A) to the MI5 of fraction (B) is greater than 20,000.

Abstract: A continuous polymerization process for producing reactive polymers comprises continuously charging into a first reaction zone at least one functional monomer and polymerizing the monomers to produce a first polymeric product having at least one functional group. This first polymeric product is then continuously directly charged into a second reaction zone together with at least one modifier reactant having a functional group that is complementary to the functional group of the first polymeric product. At least a portion of the modifier reactant reacts with at least one of the functional groups of the first polymeric product to produce a second polymeric product which incorporates at least a portion of the modifier reactant, such that the second polymeric product is a reactive polymer.

Abstract: The present invention relates to a process for the production of a propylene polymer in a multistage polymerisation process comprising the polymerisation of propylene in the presence of a catalyst in a first reaction zone comprising at least one slurry reactor to give a first polymerisation product, transferring said first product to a second reaction zone comprising at least one gas phase reactor and continuing polymerisation of propylene in the gas phase in the presence of said first polymerisation product which is characterised in that the temperature in both the slurry and the gas phase reactor is at least 75° C. and the product of at least one reactor is having an ethylene content in the range of 0.05 to 0.5 wt. %. Furthermore, the invention relates to a propylene polymer obtainable by the inventive process, to a propylene polymer which is characterised in that it comprises ethylene comonomer in an amount of 0.05 to 0.5 wt. %, is having a xylene solubles contents of 3.0 wt.

Abstract: A process for producing propylene homopolymers comprises producing a homopolymer in a reactor train having a first stage and a second stage, wherein the first stage is normally used for homopolymer production and the second stage is normally used only in the production of copolymer blends, and is left idle during homopolymer production. According to the invention, during the production of propylene homopolymer, the polymerization is carried out sequentially in both the first stage and second stage reactors.

Abstract: This invention relates to processes and plants for continuous solution polymerization. Such plan and process include a pressure source, a polymerization reactor, downstream of said pressure source, pressure let-down device, downstream of said polymerization reactor, and a separator, downstream of said pressure let-down device, wherein said pressure source is sufficient to provide pressure to said reaction mixture during operation of said process plant to produce a single-phase liquid reaction mixture in said reactor and a two-phase liquid-liquid reaction mixture in said separator in the absence of an additional pressure source between said reactor and said separator.

Abstract: The present invention relates to a preparation method for acrylonitrile-butadiene-styrene resin by continuous bulk polymerization comprising the following steps of a) preparing a mixed solution of styrene monomers and acrylonitrile monomers by adding 5–10 weight % of the mixture of styrene monomers and acrylonitrile monomers to a reaction solvent; b) preparing a polymerization solution by dissolving butadiene rubber in the above mixed solution of styrene monomers and acrylonitrile monomers; c) polymerizing with a serial injection of the prepared polymerization solution and initiator in a grafting reactor; d) polymerizing the reaction solution of the above c) in a phase inversion reactor by adding 90–95 weight % of the total mixture of styrene monomers and acrylonitrile monomers thereto; and e) polymerizing further the reaction solution of the above step d) at 130–160° C. The resin prepared by the method of the present invention thus has excellent impact strength and gloss.

Abstract: A polyethylene resin comprising from 35 to 49 wt. % of a first polyethylene fraction of high molecular weight and from 51 to 65 wt. % of a second polyethylene fraction of low molecular weight, the first polyethylene having a density of up to 0.930 g/cm3, and an HLMI of less than 0.6 g/10 min and the second polyethylene fraction comprising a high density polyethylene having a density of at least 0.969 g/cm3 and an MI2 of greater than 10 g/10 min, and the polyethylene resin, having a density of greater than 0.946 g/cm3, an HLMI of from 1 to 100 g/10 min, a dynamical viscosity, measured at 0.01 radians/second, greater than 200,000 Pa·s and a ratio of the dynamical viscosities measured at, respectively 0.01 and 1 radians/second greater than 8.

Abstract: The present invention concerns a process and an apparatus for continuous polymerisation of olefin monomers in a cascade of polymerisation reactors. According to the process, an olefin monomer is polymerised first in slurry phase in an inert hydrocarbon diluent in at least one loop reactor and then, subsequently, in gas phase in at least one gas phase reactor. According to the invention, a polymer slurry is continuously withdrawn from the loop reactor and optionally concentrated. The concentrated slurry is conducted to a high pressure flash unit in order to remove the remaining fluid phase, and fed to the gas phase reactor. With the process described in this invention, it is possible to produce bimodal polyethylene with good properties. The operation of the process is stable because of the truly continuous operation.

Abstract: Disclosed are catalyst systems and methods of making the catalyst systems/supports for the polymerization of an olefin containing a solid titanium catalyst component having a substantially spherical shape and containing a titanium compound and a support made from a magnesium compound and an alkyl silicate. The catalyst system may further contain an organoaluminum compound and an organosilicon compound. Also disclosed are methods of making an impact copolymer involving polymerizing an olefin to provide a polyolefin matrix and polymerizing a polyolefin rubber using a solid titanium catalyst component containing a titanium compound and a support made from a magnesium compound and an alkyl silicate.

Abstract: A process for preparing impact-resistant molding compositions by anionic polymerization of vinylaromatic monomers in the presence of a rubber, in a continuous-flow reactor cascade composed of at least two reactors, where the vinylaromatic monomers are fed in substreams to the reactors of the reactor cascade, and an anionic initiator and a rubber are fed at least to the first reactor, and where the reactor cascade is composed of back-mixing reactors.

Abstract: The invention relates to a process for the preparation of an olefin polymer comprising at least two polymerization stage in the presence of an olefin polymerization catalyst material, an olefin polymer produced by such process, and the use of such polymers for the production of fibres, pipes, films, moulded products and products for wire and cable applications.

Abstract: A screw for a multiple screw extruder comprises at least two conveying sections for transporting a composition comprising a polymeric resin from the feed end to the discharge end of the extruder; and at least two mixing sections comprising screw elements having two flights, wherein the ratio of the length to diameter ratio of the sum of the mixing sections to the length to diameter ratio of the screw is about 0.17 to about 0.5 and wherein the conveying sections are separated by at least one mixing section.

Abstract: The present invention concerns a high melt strength propylene polymer or copolymer suitable for manufacturing foams and thermoformed product exhibiting a melt strength of at least 3 g and comprising a high molar mass portion and a low or medium molar mass portion. The polymers are produced by subjecting propylene and optionally other olefins to polymerization in a plurality of polymerization reactors connected in series, employing different amounts of hydrogen as a molar mass modifier in at least two of the reactors, and carrying out the polymerization reaction in the presence of a catalyst system capable of catalyzing the formation of a high molar mass polymerization product having a MFR2 of less than 0.1 g/l0 min and a low or medium molar mass polymerization product having a MFR2 of more than 0.5 g/10 min.

Abstract: A catalyst system for the polymerization of ?-olefins prepared by a process which includes catalyst activation whereby a solid transitional metal compound is contacted with an organoaluminum compound and catalyst prepolymerization whereby a premonomer is prepolymerized in the presence of the activated catalyst. High activity, low fines polymerization can be achieved if in the first step of catalyst activation a first reaction mixture is prepared by contacting the solid transitional metal compound with a first organoaluminum compound in the presence of an oil and in the second step, the first reaction mixture is contacted with a second organoaluminum compound to give a second reaction mixture, the second organoaluminum compound being the same as or different from the first organoaluminum compound.

Abstract: A process for preparing impact-resistant molding compositions by anionic polymerization of vinylaromatic monomers in the presence of a rubber, in a continuous-flow reactor cascade composed of at least two reactors, where the vinylaromatic monomers are fed in substreams to the reactors of the reactor cascade, and an anionic initiator and a rubber are fed at least to the first reactor, and where the reactor cascade is composed of back-mixing reactors.

Abstract: Disclosed is a stretched film excellent in low-temperature heat sealability after corona treatment as well as that before corona treatment and/or in heat shrinkability, the stretched film being comprised of a layer comprising a copolymer of propylene with &agr;-olefin and/or ethylene such that in measurement of a DSC curve the amount of the heat absorbed in the temperature range of from T−10 (° C.) to T+10 (° C.) accounts for from 15 to 36% of the amount of the heat absorbed in the temperature range of from 53 to 170° C., wherein T denotes a temperature (° C.) at which a maximum endothermic peak appears in the DSC curve.

Abstract: A composition is disclosed having a density of at least 950 kg/m3, a fluidity index MI5 of 0.05 to 2 g/10 min and a content of alpha-olefin containing from 4 to 10 carbon atoms of from 0.15 to 1 mole %, comprising:—from 53 to 63% by weight based on the total weight of the composition of an ethylene polymer fraction (A) having a fluidity index MI2 of at least 100 g/10 min, a density of at least 969 kg/m3 and a molecular weight distribution Mw/Mn greater than 4, and −37 to 47% by weight with based on the total weight of the composition of a copolymer fraction (B) of ethylene and from 0.32 to 2.7 mole % of at least one alpha-olefin containing from 4 to 10 carbon atoms, a fluidity index MI5 Of 0.001 to 0.5 g/10 min, a density of no more than 930 kg/m3 and a molecular weight distribution Mw/Mn, greater than 4,—wherein the ratio of the MI2 of fraction (A) to the MI5 of fraction (B) is greater than 2000.

Abstract: Process for preparing a pressure-sensitive adhesive composition, characterized in that tackifiers in dispersed, melted or solid form are mixed with natural rubber latex, the water content being not more than 45% by weight.

Abstract: A polyethylene resin comprising from 35 to 49 wt. % of a first polyethylene fraction of high molecular weight and from 51 to 65 wt. % of a second polyethylene fraction of low molecular weight, the first polyethylene having a density of up to 0.930 g/cm3, and an HLMI of less than 0.6 g/10 min and the second polyethylene fraction comprising a high density polyethylene having a density of at least 0.969 g/cm3 and an MI2 of greater than 10 g/10 min, and the polyethylene resin, having a density of greater than 0.946 g/cm3, an HLMI of from 1 to 100 g/10 min, a dynamical viscosity, measured at 0.01 radians/second, greater than 200,000 Pa.s and a ratio of the dynamical viscosities measured at, respectively 0.01 and 1 radians/second greater than 8.

Abstract: A high molecular weight, medium density polyethylene (HMW, MDPE) is disclosed. The polyethylene comprises from about 85 to about 98 wt % of recurring units of ethylene and about 2 to about 15 wt % of a C3-C10 &agr;-olefin. It has a density from about 0.92 to about 0.944 g/cc, a melt index MI2 from about 0.01 to about 0.5 dg/min, and a melt flow ratio MFR from about 50 to about 300. It has a multimodal molecular weight distribution comprising a high molecular weight component and a low molecular weight component. The low molecular weight component has an MI2 from about 50 to about 600 dg/min and a density from about 0.94 to about 0.97 g/cc. A process for making the medium density polyethylene is also disclosed. The process uses a Ziegler catalyst and applies multiple reaction zones.

Abstract: The present invention is to provide a continuous anion polymerization method for preparing transparent high impact vinyl aromatic polymer comprising the steps of: i) charging and polymerizing vinyl aromatic monomers and initiator to obtain vinyl aromatic polymer in the presence of solvent and polar organic compounds in the first reactor (1a); ii) continuously charging and polymerizing vinyl aromatic monomers and conjugated diene monomers to the vinyl aromatic polymer obtained in the first reactor to obtain tapered vinyl aromatic polymer chain in the presence of organic solvent in the second reactor (1b); iii) continuously charging and polymerizing vinyl aromatic monomers and multi-functional compounds to the vinyl aromatic polymer chain obtained in the second reactor to obtain high impact vinyl aromatic polymer in the presence of organic solvent in the third reactor (1c); and iv) terminating the reaction with terminator and removing the remaining hydrocarbon solvent and unreacted monomers to obtain transparen

Abstract: Propylene polymers containing from 0 to 2.5% by weight of C2-C10-olefin comonomers have an Mw of from 350,000 to 1,000,000 g/mol, an Mw/Mn of from 4 to 10, a proportion by weight of the polymer fraction having a viscosity number of from 500 to 1400 ml/g of from 20 to 80% of the total polymer and a proportion by weight of a polymer fraction having a viscosity number of from 200 to 400 ml/g of from 80 to 20% of the total polymer and an isotactic sequence length of from 50 to 100.

Abstract: The present invention concerns high-stiffness polymer composition and a process for producing a polymer composition by nucleated with a polymeric nucleating agent containing vinyl compound units. The method comprises modifying a catalyst by polymerizing a vinyl compound in the presence of said catalyst and a strongly coordinating donor in a medium, which does not essentially dissolve the polymerized vinyl compound, and by continuing the polymerization of the vinyl compound until the concentration of unreacted vinyl compounds is less than about 0.5 wt-%. The thus obtained modified catalyst composition is used for polymerizing propylene optionally together with comonomers in the presence of said modified catalyst composition. Modification of the catalyst according to the present invention will reduce production costs and provide highly reliable catalyst activity and polymers of high stiffness.

Abstract: A polyethylene resin composition comprising 15 to 90% by weight of a polyethylene resin composition (A) and 85 to 10% by weight of a polyolefin resin composition (B), wherein the polyethylene resin composition (A) comprises ultra-high-molecular weight polyethylene (component (a-1)) having an intrinsic viscosity [&eegr;] of 10 to 40 dl/g and low-molecular weight to high-molecular weight polyethylene (component (a-2)) having an intrinsic viscosity [&eegr;] of 0.1 to 5 dl/g, the amount of said component (a-1) being more than 35% by weight and not more than 90% by weight, the amount of said component (a-2) being not less than 10% by weight and less than 65% by weight, each amount being based on the total amount of the component (a-1) and the component (a-2), and the polyethylene resin composition (A) has a density of 930 to 980 kg/m3 and an intrinsic viscosity [&eegr;] of 5 to 35 dl/g.

Abstract: The present invention is to provide a continuous anion polymerization method for preparing transparent high impact vinyl aromatic polymer comprising the steps of: i) charging and polymerizing vinyl aromatic monomers and initiator to obtain vinyl aromatic polymer in the presence of solvent and polar organic compounds in the first reactor (1a); ii) continuously charging and polymerizing vinyl aromatic monomers and conjugated diene monomers to the vinyl aromatic polymer obtained in the first reactor to obtain tapered vinyl aromatic polymer chain in the presence of organic solvent in the second reactor (1b); iii) continuously charging and polymerizing vinyl aromatic monomers and multi-functional compounds to the vinyl aromatic polymer chain obtained in the second reactor to obtain high impact vinyl aromatic polymer in the presence of organic solvent in the third reactor (1c); and iv) terminating the reaction with terminator and removing the remaining hydrocarbon solvent and unreacted monomers to obtain transparen

Abstract: This invention relates generally to synthetic polymers, generally with improved balance of processability, resilience and durability. These polymers are generally of the ethylene, alpha-olefin, diene terpolymer type.

Abstract: In a process for the anionic polymerization of vinylaromatic monomers or dienes in the presence of a lithium organyl or lithium alcoholate and a magnesium and/or an aluminum compound, a sterically hindered phenol or amine is added.

Abstract: A stable continuous production of a propylene-based block copolymer can proceed for a long time without causing accumulation of particles having a small diameter by a process having the following steps: (1) polymerizing an &agr;-olefin containing liquid propylene as a main component in the presence of hydrogen and a stereoregular polymerization catalyst in one or more polymerization reactors to obtain a polymer slurry; (2) feeding the polymer slurry to a copolymerization reactor; and (3) copolymerizing propylene and an &agr;-olefin other than propylene substantially in a gaseous phase in the presence of the stereoregular polymerization catalyst, the polymer slurry and a deactivating compound in the copolymerization reactor to obtain a propylene-block copolymer powder.

Abstract: Unique copolymers comprising propylene, ethylene and/or one or more unsaturated comonomers are characterized as having: at least one, preferably more than one, of the following properties: (i) 13C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity, (ii) a B-value greater than about 1.4 when the comonomer content of the copolymer is at least about 3 wt %, (iii) a skewness index, Six, greater than about −1.20, (iv) a DSC curve with a Tme that remains essentially the same and a Tmax that decreases as the amount of comonomer in the copolymer is increased, and (v) an X-ray diffraction pattern that reports more gamma-form crystals than a comparable copolymer prepared with a Ziegler-Natta catalyst These polypropylene polymers are made using a nonmetallocene, metal-centered, heteroaryl ligand catalyst. These polymers can be blended with other polymers, and are useful in the manufacture of films, sheets, foams, fibers and molded articles.

Abstract: The object of the present invention is to provide a polyolefin polymerization method which prevents fine particles of polymer from scattering from a fluidized bed in a gas phase polymerization reactor.

Abstract: The invention relates to a process for preparing reabsorbable polyesters by bulk polymerisation, wherein the reaction components are melted and homogenised in a stirred reactor, the reaction mixture is then transferred into a number of smaller-volume containers, the reaction mixture is polymerised in these containers and the polyester obtained is isolated by removing it from the containers, and the use of the reabsorbable polyesters thus produced for preparing reabsorbable implants.

Abstract: Provided is a continuous vapor-phase polymerization method for producing polyolefins. In the method, polymer agglomerates and aggregates are prevented from being formed, and polymer deposition on the wall of reactors and around stirring blades is prevented. The method enables continuous and stable production of high-quality polyolefins, with no pipe line clogging. The method is characterized by a specific supply mode of feeding a catalyst activity retardant such as alcohol into polymerization reactors. Specifically, the retardant is fed into the vapor phase in a polymerization reactor and into the powder phase therein through its side wall. Preferably, the retardant is fed into the powder phase through a plurality of sites of the side wall of the reactor.

Abstract: A semicrystalline propylene polymer composition with good suitability for producing biaxially oriented films and prepared by polymerizing propylene, ethylene and/or C4-C18-1-alkenes, where at least 50 mol % of the monomer units present arise from the polymerization of propylene. Also described is the use of the semicrystalline propylene polymer composition for producing films, fibers or moldings, the films, fibers and moldings made from these compositions, biaxially stretched films made from the semicrystalline propylene polymer compositions, and also a method for characterizing the semicrystalline propylene polymer compositions.

Abstract: The present invention discloses a process for manufacturing monovinylaromatic compounds containing an elastomer to provide increased toughness and strength. One particular embodiment of the invention discloses a process for manufacturing high impact polystyrene wherein styrene monomer containing a dissolved polybutadiene rubber is flowed into an elongated upflow stirred reactor containing three reaction zones, wherein the styrene and rubber are polymerized past the inversion point, then discharged to at least one additional reactor to continue their conversion to polymer.

Abstract: A new process of interpolymerizing ethylene interpolymer products having improved properties, such as increased onset of crystallization temperature, is disclosed. Preferably, the process comprises interpolymerizing a first homogeneous ethylene/alpha-olefin interpolymer and at least one second homogeneous ethylene/alpha-olefin interpolymer using at least two constrained geometry catalysts having different reactivities such that the first ethylene/alpha-olefin interpolymer has a narrow molecular weight distribution (NMWD) with a very high comonomer content and relatively high molecular weight and the second ethylene/alpha-olefin interpolymer has a NMWD with a low comonomer content and a molecular weight lower than that of the first interpolymer. The resultant first homogeneous interpolymer is combined with the resultant second homogeneous interpolymer in appropriate weight ratios resulting in the desired finished polymer structure.

Abstract: A process for homo or copolymerizing propylene, wherein propylene is polymerized in the presence of a catalyst at an elevated temperature in a reaction medium in which a major part of the reaction medium is propylene and the polymerization is carried in at least one CSTR or loop reactor, where the polymerization is carried out at a temperature and a pressure which are above the corresponding critical temperature and the pressure of the reaction medium and were the residence time is at least 15 minutes. The process can also have a subcritical loop polymerization before the supercritical stage polymerization or gas phase polymerization after the supercritical stage polymerization.

Abstract: Blend compositions containing a novel homopolymer, the use of which allows the incorporation of more comonomer in the additional components of the blend (for the same overall density) resulting in increased tie molecule formation and improvement in properties such as ESCR, toughness and impact strength are disclosed. The homopolymers are important for applications where a high density is needed to ensure certain mechanical properties like abrasion resistance, indentation resistance, pressure resistance, topload resistance, modulus of elasticity, or morphology (for the chlorination of PE to CPE) and additional advantages such as melt processability. The blend can be obtained by dry or melt mixing the already produced components, or through in-situ production by in parallel and/or in series arranged reactors. These resins can be used in applications such as films, blow molded, injection molded, and rotomolded articles, fibres, and cable and wire coatings and jacketings and, various forms of pipe.

Abstract: This invention relates to propylene homopolymer compositions obtained from metallocene catalysis wherein the polymer has a molecular weight distribution (Mw/Mn) in the range of from 4.0 to 20.0. The propylene homopolymer composition may be prepared in a multiple stage polymerization process using the same metallocene component in at least two stages. The composition may comprise isotactic homopolymer in one embodiment, and have a hexane extractables of less than 2 wt % in one embodiment. The composition is useful in making films.

Abstract: The present invention concerns a polyethylene composition particularly suitable for film blowing. The invention also concerns a process for the production thereof. The composition comprises a low molecular weight portion having a density of more than 960 kg/m3 and a high molecular weight portion. The polyethylene composition has a density of about 925-940 kg/m3 and a melt flow rate in the range of MFR21, from 5 to 40 g/10 min. A polyethylene film blown from the polyethylene composition exhibits a tensile strength at yield in transverse direction at least 15 MPa, a 1% secant modulus in machine direction at least 300 MPa and in transverse direction at least 400 MPa, and a dart drop of at least 5 g/&mgr;m.

Abstract: Ethylene, an &agr;-olefin and, optionally, a diene monomer are polymerized in a process comprising the step of contacting (1) ethylene, (2) at least one C3-C20 aliphatic &agr;-olefin, (3) optionally, at least one C4-C20 diene, (4) a catalyst comprising (a) a metallocene complex, and (b) an activator, and (5) a solvent. The process is conducted in either a single reactor or in multiple reactors, the latter configured either in series or parallel. Solvent is removed from the polymer stream in an anhydrous, first stage solvent recovery operation such that the solids concentration of the product stream is increased by at least 100 percent. Additional solvent is removed in an anhydrous, second stage solvent recovery operation from the product of the first stage solvent recovery operation such that the solids concentration of the product stream is in excess of 65 weight percent.

Abstract: A gas phase fluidized bed process is described for producing ethylene polymers having improved processability and an MWD of less than about 2.9. Multiple reactors in series or parallel may be used to produce in-situ blended polymers. Each reactor can separately have a constrained geometry catalyst or a conventional Ziegler-Natta catalyst as needed for obtaining in-situ blended polymer with the desired properties as long as there is a constrained geometry catalyst in at least one reactor. Olefin polymers can be produced according to this invention which have low susceptibility to melt fracture, even under high shear stress conditions.

Abstract: A high molecular weight, medium density polyethylene (HMW, MDPE) is disclosed. The polyethylene comprises from about 85 to about 98 wt % of recurring units of ethylene and about 2 to about 15 wt % of a C3-C10 &agr;-olefin. It has a density from about 0.92 to about 0.944 g/cc, a melt index MI2 from about 0.01 to about 0.5 dg/min, and a melt flow ratio MFR from about 50 to about 300. It has a multimodal molecular weight distribution comprising a high molecular weight component and a low molecular weight component. The low molecular weight component has an MI2 from about 50 to about 600 dg/min and a density from about 0.94 to about 0.97 g/cc. A process for making the medium density polyethylene is also disclosed. The process uses a Ziegler catalyst and applies multiple reaction zones.