Abstract: A process including polymerizing ethylene in the presence of a polymerization catalyst and hydrogen in a first polymerization reactor to produce a first slurry; withdrawing a first stream of the slurry from the first polymerization reactor; directing the slurry stream into a second polymerization reactor; polymerizing ethylene in the presence of the first ethylene polymer, the polymerization catalyst, and hydrogen in a second polymerization reactor to produce a second slurry; withdrawing from the second polymerization reactor a second slurry stream having a solids concentration higher than the average solids concentration of the second slurry within the second polymerization reactor; withdrawing from the second polymerization reactor a third slurry stream having a solids concentration lower than the average solids concentration of the second slurry within the second polymerization reactor; and directing at least a part of the second slurry stream into one of the first and second polymerization reactors.

Abstract: Method for preparing olefin polymer in a loop reactor, said loop reactor comprises a first outlet for withdrawing polymer slurry from the loop reactor, and a second outlet for withdrawing a polymer slurry from the loop reactor, wherein the first outlet is located such that polymer slurry is withdrawn having a concentration of polymer which is equal or higher than the average concentration of polymer in the loop reactor, and the second outlet is located such that polymer slurry is withdrawn having a concentration of polymer which is lower than the average concentration of polymer in the loop reactor, the method comprises the steps of supplying olefin monomers and a catalytic system to the loop reactor to form a polymer slurry in the loop reactor, and controlling the total amount of polymer and/or the total amount of polymer slurry withdrawn from the loop reactor by adjusting the ratio of polymer slurry withdrawn through the first outlet and polymer slurry withdrawn through the second outlet.

Abstract: The invention relates to a coated pipe comprising a core, an adhesion layer coated on the core and an outer coating layer coated on the adhesion layer, wherein at least the adhesion layer comprises a propylene polymer composition comprising: (A) a propylene homo- or copolymer, and (B) an elastomeric component and to the use of such a propylene polymer composition for coating a pipe.

Abstract: The present invention relates to a polymer composition, comprising (i) a polypropylene homopolymer, (ii) a polypropylene random copolymer, prepared by copolymerization of propylene with an olefin comonomer and having an amount of olefin comonomer units of 0.2 to 5 wt %, and (iii) an elastomeric copolymer of propylene and at least one olefin comonomer, the polymer composition having a tensile modulus, determined according to ISO 527-2/1 B at 1 mm/min. and 230 C, of at least 1200 MPa.

Abstract: The present invention relates to an adhesive composition providing high peel strength in particular at high temperatures, an article comprising a layer of the adhesive and the use of the adhesive.

Abstract: The present invention relates to a polymer composition, comprising (i) a polypropylene homopolymer, (ii) a polypropylene random copolymer, prepared by copolymerization of propylene with an olefin comonomer and having an amount of olefin comonomer units of 0.2 to 5 wt %, and (iii) an elastomeric copolymer of propylene and at least one olefin comonomer, the polymer composition having a tensile modulus, determined according to ISO 527-2/1B at 1 mm/min. and 23° C., of at least 1200 MPa.

Abstract: The present invention relates to a structure comprising (i) a layer or profile (A) composed of a first material, and (ii) a polyolefin layer or profile (B) adjacent to layer or profile (A) which is composed of a composition comprising a base resin comprising a polyolefin, characterized in that the surface of any or both of layer or profile (A) and layer or profile (B) has/have been treated with a composition comprising an organosilicon compound before (A) and (B) are brought adjacent to each other, to a process for the production of such a structure, to an article, in particular a coated pipe, comprising such a structure and to the use of a composition comprising an organosilicon compound as an adhesion promoter in such a structure.

Abstract: The invention relates to a coated pipe comprising a core, an adhesion layer coated on the core and an outer coating layer coated on the adhesion layer, wherein at least the adhesion layer comprises a propylene polymer composition comprising: (A) a propylene homo- or copolymer, and (B) an elastomeric component and to the use of such a propylene polymer composition for coating a pipe.

Abstract: The present invention relates to a polymer composition, comprising (i) a polypropylene homopolymer, (ii) a polypropylene random copolymer, prepared by copolymerization of propylene with an olefin comonomer and having an amount of olefin comonomer units of 0.2 to 5 wt %, and (iii) an elastomeric copolymer of propylene and at least one olefin comonomer, the polymer composition having a tensile modulus, determined according to ISO 527-2/1B at 1 mm/min. and 23° C., of at least 1200 MPa.

Abstract: The present invention relates to an adhesive composition providing high peel strength in particular at high temperatures, an article comprising a layer of the adhesive and the use of the adhesive.

Abstract: The present invention relates to a polymer composition, comprising (i) a polypropylene homopolymer, (ii) a polypropylene random copolymer, prepared by copolymerization of propylene with an olefin comonomer and having an amount of olefin comonomer units of 0.2 to 5 wt %, and (iii) an elastomeric copolymer of propylene and at least one olefin comonomer, the polymer composition having a tensile modulus, determined according to ISO 527-2/1 B at 1 mm/min. and 230 C, of at least 1200 MPa.

Abstract: The present invention relates to a polymer composition, comprising (i) a polypropylene-based matrix which comprises a polypropylene random copolymer prepared by copolymerization of propylene with an olefin comonomer, wherein the amount of olefin comonomer units is within the range of (0.2) wt % to (5) wt %, based on the weight of the polypropylene-based matrix, and (ii) an elastomeric copolymer of propylene and at least one olefin comonomer, the polymer composition having a storage modulus G1 at a loss modulus G?=5 kPa of G?(5 kPa)<(3100) Pa, measured at (220° C.).

Abstract: Polymers of propylene with one or two olefin comonomers are produced through the use of a polymerization catalyst supported on a carrier produced by spray crystallization and having a maximum dimension of 55 ?m. Copolymers of superior properties are obtained, and the production process is de-snagged.

Abstract: There is provided a process for the copolymerisation of propylene with at least one C4-20 ?-olefin or C4-20 diene in a reaction medium in the presence of a catalyst system at a temperature of greater that 80° C. or at a temperature and pressure above the critical temperature and pressure of the reaction medium. Under such conditions, comonmer incorporation is higher than under standard conditions.

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: Polymers of propylene with one or two olefin comonomers are produced through the use of a poymerisation catalyst supported on a carrier produced by spray crystallisation and having a maximum dimension of ?m. Copolymers of superior properties are obtained, and the production process is de-snagged.

Abstract: There is provided a process for the copolymerisation of propylene with at least one C4-20 &agr;-olefin or C4-20 diene in a reaction medium in the presence of a catalyst system at a temperature of greater that 80° C. or at a temperature and pressure above the critical temperature and pressure of the reaction medium. Under such conditions, comonomer incorporation is higher than under standard conditions.

Abstract: A process for the production of a propylene based polymer, the process comprising the following steps: (a) a first polymerization stage comprising homopolymerizing propylene or copolymerizing propylene and at least one alpha-olefin in the presence of an alpha-olefin polymerization catalyst whereby to produce a polypropylene component; (b) a second polymerization stage comprising copolymerizing ethylene and at least one alpha-olefin in the presence of an alpha-olefin polymerization catalyst whereby to produce an ethylene/alpha-olefin copolymer component; and (c) blending the polymer components produced in steps (a) and (b) whereby to produce a polymer blend, wherein the first and second polymerization stages are effected in separate polymerization reactors connected in parallel.

Abstract: The present invention relates to a process for polymerizing &agr;-olefins in at least two stages, the first stage comprising at least one bulk reactor and optionally at least one gas phase reactor for forming the &agr;-olefin polymer matrix and the second stage comprising at least one additional gas phase reactor for copolymerization of ethylene with said polymer matrix. In the second stage an antifouling composition is fed into said gas phase reactor(s) for preventing fouling in the second stage.

Abstract: The invention provides a process for the production of a propylene based polymer, said process comprising the following steps: (a) a first polymerization stage comprising homopolymerizing propylene or copolymerizing propylene and at least one &agr;-olefin in the presence of an &agr;-olefin polymerization catalyst whereby to produce a polypropylene component; (b) a second polymerization stage comprising copolymerizing ethylene and at least one &agr;-olefin in the presence of an &agr;-olefin polymerization catalyst whereby to produce an ethylene/&agr;-olefin copolymer component; and (c) blending the polymer components produced in steps (a) and (b) whereby to produce a polymer blend, wherein said first and second polymerization stages are effected in separate polymerization reactors connected in parallel.