US 9,809,666 B2
Polypropylene composition with improved impact resistance for pipe applications
Cristian Hedesiu, Abu Dhabi (AE); and Kauno Alastalo, Porvoo (FI)
Assigned to ABU DHABI POLYMERS COMPANY LIMITED (BOROUGE), Abu Dhabi (AE); and BOREALIS AG, Vienna (AT)
Appl. No. 14/781,186
Filed by ABU DHABI POLYMERS COMPANY LIMITED (BOROUGE), Abu Dhabi (AE); and BOREALIS AG, Vienna (AT)
PCT Filed Apr. 22, 2014, PCT No. PCT/EP2014/001068
§ 371(c)(1), (2) Date Sep. 29, 2015,
PCT Pub. No. WO2014/173530, PCT Pub. Date Oct. 30, 2014.
Claims priority of application No. 13002099 (EP), filed on Apr. 22, 2013.
Prior Publication US 2016/0053034 A1, Feb. 25, 2016
Int. Cl. C08F 210/06 (2006.01); C08L 23/16 (2006.01); C08L 23/14 (2006.01); F16L 9/12 (2006.01); B29B 9/06 (2006.01); C08J 5/00 (2006.01); B29K 23/00 (2006.01); B29K 105/00 (2006.01)
CPC C08F 210/06 (2013.01) [B29B 9/06 (2013.01); C08J 5/00 (2013.01); C08L 23/142 (2013.01); F16L 9/12 (2013.01); B29K 2023/06 (2013.01); B29K 2023/12 (2013.01); B29K 2105/0085 (2013.01); B29K 2105/0094 (2013.01); B29K 2995/0089 (2013.01); C08J 2323/14 (2013.01); C08L 2203/18 (2013.01); C08L 2205/025 (2013.01); C08L 2314/02 (2013.01)] 20 Claims
 
1. A polypropylene composition suitable for pipe applications comprising:
a propylene random copolymer with at least one comonomer selected from alpha-olefins with 2 or 4 to 8 carbon atoms,
wherein the propylene random copolymer comprises at least (i) a propylene random copolymer fraction having a low molecular weight, which is a low molecular weight fraction, and (ii) a propylene random copolymer fraction having a high molecular weight, which is a high molecular weight fraction, wherein the weight average molecular weight of the low molecular weight fraction is lower than that of the high molecular weight fraction,
wherein the polypropylene composition has a melt flow rate MFR2 (2.16 kg, 230° C.) of 0.05 to 1.0 g/10 min, determined according to ISO 1133, a polydispersity index (PI) of 2.0 to 7.0, and a Charpy Notched Impact Strength at 0° C. of more than 6.5 kJ/m2, determined according to ISO 179/1eA:2000 using notched injection moulded specimens; and
wherein the polypropylene composition does not comprise a polymeric nucleating agent.