A PROCESS FOR PRODUCING A MULTIMODAL ETHYLENE POLYMER AND FILMS PREPARED THEREFROM

A process for producing a multimodal ethylene polymer comprising the steps of (i) polymerising ethylene in a first polymerisation step in the presence of a Ziegler-Natta polymerisation catalyst to produce a first ethylene homopolymer (PEI) having a melt flow rate MFR2 of from 100 to 300 g/10 min (ISO 1133-1 at 190° C. under 2.16 kg load); (ii) polymerising ethylene in a second polymerisation step in the presence of the first ethylene homopolymer to produce a first ethylene polymer mixture (PEM1) comprising the first ethylene homopolymer and a second ethylene homopolymer, said first ethylene polymer mixture having a melt flow rate MFR2 of from 200 to 1000 g/10 min, and wherein the MFR2 of the first ethylene homopolymer (PEI) is lower than the MFR2 of the first ethylene polymer mixture (PEM1); and (iii) copolymerising ethylene and at least one alpha-olefin comonomer in a third polymerisation step in the presence of the first ethylene polymer mixture to produce a second ethylene polymer mixture (PEM2) comprising the first ethylene polymer mixture and a third ethylene copolymer (PE3), said second ethylene polymer mixture having a density of from 937 to 950 kg/m3 (ISO 1183-2) and a melt flow rate MFR5 of from 0.1 to 5.0 g/10 min (ISO 1133-1 at 190° C. under 5 kg load).