초록 ▼

A blown film having a thickness from 8 to 200 μm and dart drop impact DDI of more than 400 g, comprising a polyethylene molding composition having a multimodal molar mass distribution; a density from 0.940 to 0.948 g/cm3; an MFR190/5, from 0.10 to 0.50 dg/min; comprising: 40 to 60% of an ethylene ho

A blown film having a thickness from 8 to 200 μm and dart drop impact DDI of more than 400 g, comprising a polyethylene molding composition having a multimodal molar mass distribution; a density from 0.940 to 0.948 g/cm3; an MFR190/5, from 0.10 to 0.50 dg/min; comprising: 40 to 60% of an ethylene homopolymer A having a molecular weight;25 to 45% of a copolymer B of ethylene and at least one comonomer selected from the group of olefins having from 4 to 8 carbon atoms, said copolymer B having a molecular weight higher than said molecular weight of homopolymer A; and10 to 30% of a copolymer C of ethylene and at least one comonomer, said copolymer C having a molecular weight higher than said molecular weight of copolymer B, all percentages being based on the total weight of the molding composition.

대표청구항 ▼

1. A blown film having: (i) a thickness in the range from 8 to 200 μm;(ii) a dart drop impact of more than 400 g (a) when the dart drop impact is measured according to ASTM D1709 method A; and,(b) when the dart drop impact is measured on a film having a thickness of 20 μm, wherein the blown film com

1. A blown film having: (i) a thickness in the range from 8 to 200 μm;(ii) a dart drop impact of more than 400 g (a) when the dart drop impact is measured according to ASTM D1709 method A; and,(b) when the dart drop impact is measured on a film having a thickness of 20 μm, wherein the blown film comprises a polyethylene composition, wherein the polyethylene composition has: (i) a multimodal molar mass distribution;iii) a density between 0.940 and 0.948 g/cm3, (a) when the density is measured according to ISO 1183, and(b) when the density is measured at a temperature of 23° C.; and(iii) an MFR190/5 between 0.10 and 0.50 dg/min, (a) when the MFR190/5 is measured according to ISO 1133, and(b) when the MFR190/5 is measured after the polyethylene composition has been extruded;wherein the said polyethylene composition comprises:(A) 45 to 55% by weight, based on the total weight of the polyethylene composition, of a first ethylene polymer fraction comprising an ethylene homopolymer A having a first molecular weight;(B) 30 to 40% by weight, based on the total weight of the polyethylene composition, of a second ethylene polymer fraction comprising: (i) a first copolymer B of ethylene, and(ii) at least one first comonomer selected from the group of olefins having from 4 to 8 carbon atoms,wherein the first copolymer B has a second molecular weight, andwherein the second molecular weight is higher than the first molecular weight; and(C) 15 to 25% by weight, based on the total weight of the polyethylene composition, of a third ethylene polymer fraction comprising: (i) a second copolymer C of ethylene, and(ii) at least one second comonomer,wherein the second copolymer C has a third molecular weight, andwherein the third molecular weight is higher than said second molecular weight,wherein the polyethylene composition has a viscosity number VN2 in the range from 320 to 380 cm3/g. 2. The blown film of claim 1, wherein said first comonomer and said second comonomer are independently selected from the group consisting of 1-butene, 1-pentene, 1-hexene, 1-octene, 4-methyl-1-pentene and mixtures thereof. 3. The blown film of claim 1, wherein the MFR190/5 of the polyethylene composition is in the range from 0.15 to 0.23 dg/min. 4. The blown film of claim 3, wherein the polyethylene composition has a broad trimodal mass distribution and a viscosity number VN3, measured in accordance with ISO/R 1191 in decalin at a temperature of 135° C., of 300 to 480 cm3/g. 5. A film comprising; a polyethylene composition, wherein the polyethylene composition has: (i) a multimodal molar mass distribution;(ii) a density between 0.940 and 0.948 g/cm3, (a) when the density is measured according to ISO 1183, and(b) when the density is measured at a temperature of 23° C.;(iii) an MFR190/5 between 0.10 and 0.50 dg/min, (a) when the MFR190/5 is measured according to ISO 1133, and(b) when the MFR190/5 is measured after the polyethylene composition has been extruded;wherein the said polyethylene composition comprises:(A) 45 to 55% by weight, based on the total weight of the polyethylene composition, of a first ethylene polymer fraction comprising an ethylene homopolymer A having a first molecular weight;(B) 30 to 40% by weight, based on the total weight of the polyethylene composition, of a second ethylene polymer fraction comprising: (i) a first copolymer B of ethylene, and(ii) at least one first comonomer selected from the group of olefins having from 4 to 8 carbon atoms,wherein the first copolymer B has a second molecular weight, andwherein the second molecular weight is higher than the first molecular weight; and(C) 15 to 25% by weight, based on the total weight of the polyethylene composition, of a third ethylene polymer fraction comprising: (i) a second copolymer C of ethylene, and(ii) at least one second comonomer,wherein the second copolymer C has a third molecular weight, andwherein the third molecular weight is higher than said second molecular weight,wherein the film has a thickness of 8 to 200 μm wherein the polyethylene composition has a viscosity number VN2 in the range from 320 to 380 cm3/g. 6. A blown film having: (i) a thickness in the range from 8 to 200 μm;(ii) a dart drop impact of more than 400 g (a) when the dart drop impact is measured according to ASTM D1709 method A; and,(b) when the dart drop impact is measured on a film having a thickness of 20 μm, wherein the blown film comprises a polyethylene composition, wherein the polyethylene composition has: (i) a multimodal molar mass distribution;(ii) a density between 0.944 and 0.948 g/cm3, (a) when the density is measured according to ISO 1183, and(b) when the density is measured at a temperature of 23° C.;(iii) an MFR190/5 between 0.15 and 0.23 dg/min, (a) when the MFR190/5 is measured according to ISO 1133, and(b) when the MFR190/5 is measured after the polyethylene composition has been extruded;wherein the said polyethylene composition comprises:(A) 45 to 55% by weight, based on the total weight of the polyethylene composition, of a first ethylene polymer fraction comprising an ethylene homopolymer A having a first molecular weight;(B) 30 to 40% by weight, based on the total weight of the polyethylene composition, of a second ethylene polymer fraction comprising: (i) a first copolymer B of ethylene, and(ii) at least one first comonomer selected from the group of olefins having from 4 to 8 carbon atoms,wherein the said first copolymer B has a second molecular weight, andwherein the second molecular weight is higher than the first molecular weight; and(C) 15 to 25% by weight, based on the total weight of the polyethylene composition, of a third ethylene polymer fraction comprising: (i) a second copolymer C of ethylene, and(ii) at least one second comonomer,wherein the second copolymer C has a third molecular weight, andwherein the third molecular weight is higher than said second molecular weight,wherein the polyethylene composition has a viscosity number VN2 in the range from 320 to 380 cm3/g.