Pipe Comprising a Metallocene-Catalyzed Polyethylene Resin

摘要

The invention relates to a pipe comprising at least one metallocene-catalyzed polyethylene resin, wherein the polyethylene resin has a multimodal molecular weight distribution and comprises at least two metallocene-catalyzed polyethylene fractions A and B, wherein fractions A and B are prepared in different reactors of at least two reactors connected in series, wherein the polyethylene resin comprises:
at least 30% by weight and at most 50% by weight of the polyethylene fraction A, based on the total weight of the polyethylene resin, wherein fraction A has a melt index MI2 of at least 50 g/10 min as determined on the fluff of fraction A according to ISO 1133:1997 condition D at a temperature of 190° C. and under a load of 2.16 kg;

wherein fraction B has a density of at most 0.9210 g/cm3; and wherein the polyethylene resin has a melt index MI5 of at least 0.10 g/10 min and of at most 1.0 g/10 min as determined according to ISO 1133:1997, condition T, at 190° C. and under a load of 5 kg; wherein the polyethylene resin has an HLMI of at least 4.0 g/10 min and at most 14.0 g/10 min, as measured according to the procedure of ISO 1133:1997 condition G with a temperature of 190° C. and a load of 21.6 kg; and a density of at least 0.9420 g/cm3 and of at most 0.9460 g/cm3 as determined according to the procedure of ASTM D-1505 at a temperature of 23° C.

主权项

1. A pipe comprising at least one metallocene-catalyzed polyethylene resin, wherein the polyethylene resin has a multimodal molecular weight distribution and comprises at least two metallocene-catalyzed polyethylene fractions A and B, wherein fractions A and B are prepared in different reactors of at least two reactors connected in series, wherein the polyethylene resin comprises:
at least 30% by weight and at most 50% by weight of the polyethylene fraction A, based on the total weight of the polyethylene resin, wherein fraction A has a melt index MI2 of at least 50 g/10 min as determined on the fluff of fraction A according to ISO 1133:1997 condition D at a temperature of 190° C. and under a load of 2.16 kg; wherein the polyethylene resin has a melt index MI5 of at least 0.10 g/10 min and of at most 1.0 g/10 min as determined according to ISO 1133:1997, condition T, at 190° C. and under a load of 5 kg; an HLMI of at least 4.0 g/10 min and at most 14.0 g/10 min, as measured according to the procedure of ISO 1133:1997 condition G with a temperature of 190° C. and a load of 21.6 kg; and a density of at least 0.9420 g/cm3 and of at most 0.9460 g/cm3 as determined according to the procedure of ASTM D-1505 at a temperature of 23° C.; and wherein fraction B has a density of at most 0.9210 g/cm3.