abstract |
The invention relates to a polyethylene moulding composition having a multimodal molecular mass distribution and comprising a first ethylene homopolymer fraction (I), a second ethylene copolymer fraction (II) and a third ethylene copolymer fraction (III). The moulding composition has a density at a temperature of 23 °C in the range from 0.945 to 0.953 g/cm3, an MFR (190 °C/5 kg) in the range from 2 to 7 g/10 min and a viscosity number VN3 of the total mix of ethylene homopolymer fraction (I), copolymer fraction (II) and ethylene copolymer fraction (III), measured in accordance with ISO/R 1191 in decalin at a temperature of 135 °C, in the range from 200 to 250 cm3/g. The invention further relates to the use of such a moulding composition for producing high-strength injection-molded screw cap closures for bottles comprising beverages, especially carbonated beverages. |