Borealis Technology Oy

Merete Skar

Ole Jan Myhre

Kalle Kallio

Irene Helland

Arja Lehtinen

Hans Georg Daviknes

Geir Morten Johansen

Markku Vahteri

Hilkka R Knuuttila

Arild Follestad

Harri Hokkanen

Hans Eklind

Jari Äärilä

Marja Ora

Kjetil Larsen Borve

Eija Lappi

Kjetil Larsen Brove

Jani Äärilä

Esa Kinnunen

Arno Johansen

Hans Georg Daviksnes

Håkon Tvermyr

Jarmo Lindroos

Alexander Krajete

Holger Pöhler

A multimodal medium density polyethylene polymer obtainable using single site catalysis which comprises at least:

Multimodal medium density polyethylene polymer composition

A shrink film comprising a polyethylene film of thickness 5 to 500 &#x3bc;m, wherein the polyethylene comprises an ethylene homopolymer-copolymer mixture having a molecular weight distribution in the range of 5 to 40, and a weight average molecular weight of at least 100 kD.

Shrink film

A shrink film comprising a polyethylene film, characterized in that said polyethylene is an ethylene copolymer mixture having a molecular weight distribution in the range 10 to 35, a density of 915 to 940 kg/m, a weight average molecular weight of at least 100000 D and an MFR(190&#xb0; C.) of 0.1 to 0.9 kg/m, which copolymer mixture is produced by a two or more stage copolymerization of ethylene and 2 to 10% mole (relative to ethylene) of a Calpha-olefin comonomer in a series of reactors including at least one slurry loop reactor and at least one gas phase reactor using a heterogeneous Ziegler-Natta catalyst.

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

Polymer film

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&#xb0; C.; (3) at least 25%, of the ethylene copolymer composition elutes in TREF at a temperature of higher than 75&#xb0; C.; (4) none of the ethylene copolymer composition elutes in TREF at a temperature of higher than 100&#xb0; 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 Calpha-olefin in the present of a single site catalyst; (6) the ethylene copolymer composition has a density of between 905 and 930 kg/m, and an MFRbetween 0.3 and 4.0 g/10 min.

Heat sealable polyethylene film and method for its preparation

This invention concerns process for producing polyethylene compositions, films prepared thereof and process for the preparation of the films. The process comprises subjecting ethylene, optionally hydrogen and comonomers to polymerization or copolymerization reactions in a multistage polymerization. At least one polymerization stage is conducted essentially in the absence of hydrogen. The polymerization reactions are carried out in the presence of a single-site catalyst capable of forming a composition comprising a low molecular weight component with MFR of at least 10 g/10 min and a density higher than the density of the composition and a high molecular weight component. The melt flow rate of the composition is in the range MFR &equals;0.1-5.0 g/10 min and the density of the composition is 915-960 kg/m . The invention makes it possible to produce polyethylene compositions for manufacturing films with a good balance between optical and mechanical properties.

Polymer composition, a process for the production thereof and films prepared thereof

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Stathelle, Norway

Merete Skar