US 12,227,633 B2
Polyethylene composition for pipe applications with improved sagging properties
Antti Tynys, Abu Dhabi (AE); Jarmo Harjuntausta, Helsinki (FI); and Mohana Murali Adhyatmabhattar, Abu Dhabi (AE)
Assigned to ABU DHABI POLYMERS COMPANY LIMITED (BOROUGE), Abu Dhabi (AE); and BOREALIS AG, Vienna (AT)
Filed by ABU DHABI POLYMERS COMPANY LIMITED (BOROUGE), Abu Dhabi (AE); and BOREALIS AG, Vienna (AT)
Filed on Oct. 26, 2020, as Appl. No. 17/080,767.
Application 17/080,767 is a continuation of application No. 15/107,431, previously published as PCT/EP2014/003462, filed on Dec. 22, 2014.
Claims priority of application No. 13006049 (EP), filed on Dec. 23, 2013.
Prior Publication US 2021/0070969 A1, Mar. 11, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. C08L 23/08 (2006.01); C08K 3/04 (2006.01); C08L 23/06 (2006.01); F16L 9/12 (2006.01)
CPC C08L 23/0815 (2013.01) [C08K 3/04 (2013.01); C08L 23/06 (2013.01); F16L 9/12 (2013.01); C08L 2203/18 (2013.01); C08L 2308/00 (2013.01); C08L 2314/02 (2013.01)] 11 Claims
 
1. A bimodal polyethylene composition consisting of
a bimodal base resin (A) comprising:
a copolymer of ethylene and at least one comonomer selected from alpha-olefins having from three to twelve carbon atoms,
wherein the ethylene copolymer comprises a low molecular weight component (A-1) and a high molecular weight component (A-2) with the low molecular weight component (A-1) having a lower weight average molecular weight than the high molecular weight component (A-2),
(B) carbon black in an amount of 1.0 to 10 wt % based on the total amount of the polyethylene composition, and
(C) optional stabilizing additives;
wherein the base resin (A) has a density of equal to or more than 943 kg/m3 to equal to or less than 957 kg/m3, determined according to ISO 1183, and
the composition has a melt flow rate MFR5 (190° C., 5 kg) of equal to or more than 0.12 g/10 min to equal to or less than 0.20 g/10 min, determined according to ISO 1133, a melt flow rate MFR21 (190° C., 21.6 kg) of equal to or more than 5.6 g/10 min to equal to or less than 6.5 g/10 min, determined according to ISO 1133, a shear thinning index SHI2.7/210 of equal to or more than 120 to equal to or less than 130 and a viscosity at a constant shear stress of 747 Pa, eta747, of equal to or more than 700 kPas to equal to or less than 1200 kPas, and
wherein the low molecular weight component (A-1) has a melt flow rate MFR2 (190° C., 2.16 kg) of 200 g/10 min to 400 g/10 min, determined according to ISO 1133.