| 摘要 |
A single- or multilayer threaded pipe, wherein at least one layer is produced from a polyolefin composition comprising (percentages express on the basis of the sum of components (A) and (B)): (A) 65-90 wt % of a heterophasic polypropylene composition comprising (percentages expressed on the basis of the polypropylene composition): (1) 65-95 wt % of a propylene polymer selected from propylene homopolymer and co- and terpolymers of propylene with a comonomer selected from ethylene, a C4-C10 alpha-olefin and a mixture thereof, said polymer containing 0.1-10 wt % of comonomer units, being insoluble in xylene at 25° C. in an amount over 85 wt %, having a polydispersity index ranging from 4 to 13 and an intrinsic viscosity ([eta]1) value of over 2.2 dl/g; and (2) 5-35 wt % of an olefin polymer of ethylene with propylene or a C4-C10 alpha-olefin having an ethylene content ranging from 15 to 85 wt % and an intrinsic viscosity of the fraction soluble in xylene ([eta]2) of at least 1.4 dl/g; wherein the ratio of the intrinsic viscosity value of propylene polymer (1) to that of olefin polymer (2) ([eta]/[eta]2) ranges from 0.45 to 1.6; and (B) 10-35 wt % of a at least one filler selected among calcium carbonate, talc, wollastonite or mixtures thereof.
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