Propylene polymers having low-temperature impact strength

Claim 2

A propylene polymer containing A) a semicrystalline propylene homopolymer having a melting point of 125 to 165° C. and a glass transition temperature which is greater than -10° C. and B) a semicrystalline propylene homopolymer having a melting point below 130° C. and a glass transition temperature which is less than or equal to -10° C. or a non-crystallizing propylene homopolymer having a glass transition temperature which is less than or equal to -10° C.

Claim 3

A propylene polymer as defined in claim 1, obtained by preparing the propylene homopolymer B) using a catalyst system which contains, as active components, a metallocene complex of the formula I or II ##STR7## where M 1 is a metal of group IVb, Vb or VIb of the Periodic Table, R 1 and R 2 are identical or different and are each hydrogen, C 1 -C 10 -alkyl, C 1 -C 10 -alkoxy, C 6 -C 10 -aryl, C 6 -C 10 -aryloxy, C 2 -C 10 -alkenyl, C 7 -C 40 -arylalkyl, C 7 -C 40 -alkylaryl, C 8 -C 40 -arylalkenyl or halogen, R 3 and R 4 are identical or different and are each hydrogen, halogen, C 1 -C 10 -alkyl which may be halogenated, C 6 -C 10 -aryl, -NR 2 10 , -SR 10 , -OSiR 3 10 , -SiR 3 10 or -PR 2 10 where R 10 is halogen, C 1 -C 10 -alkyl or C 6 -C 10 -aryl, R 5 and R 6 are identical or different and have the meaning stated for R 3 and R 4 , with the proviso that R 5 and R 6 are not hydrogen, R 7 is ##STR8## =BR 11 , =AlR 11 , -Ge-, -Sn-, -O-, -S-, =SO, =SO 2 , =NR 11 , =CO =PR 11 or =P(O)R 11 , R 11 , R 12 and R 13 are identical or different and are each hydrogen, halogen, C 1 -C 10 -alkyl, C 1 -C 10 fluoralkyl, C 6 -C 10 -aryt, C 6 -C 10 -fluoraryl, C 1 -C 10 -alkoxy, C 2 -C 10 -alkenyl, C 7 -C 40 -arylalkyl, C 8 -C 40 -arylalkenyl or C 7 -C 40 -alkylaryl or R 11 and R 12 or R 11 and R 13 each form a ring with the atoms linking them, M 2 is silicon, germanium or tin, R 8 and R 9 are identical or different and each have the meaning stated for R 11 and m and n are identical or different and are each zero, 1 or 2, m plus n being zero, 1 or 2, and a oligomeric alumina compound.

Claim 4

A propylene polymer as defined in claim 1, obtained by preparing the propylene homopolymer A) using a Ziegler-Natta catalyst system.

Claim 5

A propylene polymer as defined in claim 1, obtained by preparing the propylene homopolymer A) using a catalyst system which contains, as active components, metallocene complexes of metals of subgroup IV or V of the Periodic Table, which complexes differ from those of the formula I and II, and an oligomeric alumina compound.

Claim 6

A process for the preparation of a propylene polymer as defined in claim 1, wherein components A) and B) are prepared together in one reaction zone.

Claim 7

A process for the preparation of a propylene polymer as defined in claim 5, which is carried out in the gas phase.

Claim 8

A fiber, film or molding obtained from a propylene polymer as defined in claim 1 as the essential component.