Propylene polymer compositions
View Patent ↗The invention relates to propylene polymer compositions comprising 45-79 parts per weight of a propylene homo- or copolymer, 10-27 parts per weight of a first elastomeric ethylenepropylene copolymer, 5-22 parts per weight of a second elastomeric ethylene-propylene copolymer, 1-15 parts per weight of an elastomeric ethylene-1-octene copolymer and 5-15 parts per weight of inorganic filler. The propylene polymer compositions are suitable for injection molding of large articles, which do not show flow marks and which have a good impact strength/stiffness ratio.
1. A propylene polymer composition comprising
A) 45-79 parts per weight of a propylene polymer comprising a propylene homopolymer and/or a propylene copolymer with up to 10 mol % of ethylene and/or one or more C 4 -C 8 α-olefins, the propylene polymer having an MFR≧80 g/10 min,
B) 10-27 parts per weight of an elastomeric ethylene-propylene copolymer having an intrinsic viscosity IV of ≦2.4 dl/g and an ethylene content of at least 75 mol %,
C) 5-22 parts per weight of an elastomeric ethylene-propylene copolymer having an intrinsic viscosity IV of 4.0-6.5 dl/g and an ethylene content of up to 70 mol %,
D) 1-15 parts per weight of an elastomeric ethylene-1-octene copolymer having an ethylene content of at least 80 mol % and having a melt index MI (190° C., 2.16 kg) of 3-100 g/10 min and
E) 5-15 parts per weight of inorganic filler.
2. A propylene polymer composition, comprising
A) 50-65 parts per weight of a propylene polymer comprising a propylene homopolymer and/or a propylene copolymer with up to 10 mol % of ethylene and/or one or more C 4 -C 8 α-olefins, the propylene polymer having an MFR≧80 g/10 min,
B) 10-23 parts per weight of an elastomeric ethylene-propylene copolymer having an intrinsic viscosity IV of ≦2.2 dl/g and an ethylene content of at least 80 mol %,
C) 5-15 parts per weight of an elastomeric ethylene-propylene copolymer having an intrinsic viscosity IV of 4.0-6.5 dl/g and an ethylene content of up to 70 mol %,
D) 3-10 parts per weight of an elastomeric ethylene-1-octene copolymer having an ethylene content of at least 80 mol % and having a melt index MI (190° C., 2.16 kg) of 3-50 g/10 min and
E) 5-15 parts per weight of inorganic filler.
3. A propylene polymer composition according to claim 1 or 2 , further comprising 0.01-2 parts per weight of nucleating agent.
4. A propylene polymer composition according to claim 1 or 2 , wherein the ethylene content of the elastomeric ethylene-propylene copolymer B is 80-97 mol %.
5. A propylene polymer composition according to claim 1 or 2 , wherein the ethylene content of the elastomeric ethylene-propylene copolymer C is 43-70 mol %.
6. A propylene polymer composition according to claim 1 or 2 , wherein the propylene polymer A comprises a propylene homopolymer having an isotacticity IRτ of ≧0.980.
7. Process for producing a propylene polymer composition according to claim 1 , comprising mixing
A) 45-79 parts per weight of a propylene polymer comprising a propylene homopolymer and/or a propylene copolymer with up to 10 mol % of ethylene and/or one or more C 4 -C 8 α-olefins, the propylene polymer having an MFR≧80 g/10 min,
B) 10-27 parts per weight of an elastomeric ethylene-propylene copolymer having an intrinsic viscosity IV of ≦2.4 dl/g and an ethylene content of at least 75 mol %,
C) 5-22 parts per weight of an elastomeric ethylene-propylene copolymer having an intrinsic viscosity IV of 4.0-6.5 dl/g and an ethylene content of up to 70 mol %,
D) 1-15 parts per weight of an elastomeric ethylene-1-octene copolymer having an ethylene content of at least 80 mol % and having a melt index MI (190° C., 2.16 kg) of 3-100 g/10 min and
E) 5-15 parts per weight of inorganic filler, melting and homogenizing and cooling and pelletizing the mixture.
8. A propylene polymer composition according to claim 1 or 2 , wherein the nucleating agent comprises α-nucleating agent.
9. A propylene polymer composition according to claim 1 , wherein the isotacticity Irτ is 0.980-0.995.
10. Process for producing a propylene polymer composition comprising mixing
A) 50-65 parts per weight of a propylene polymer comprising a propylene homopolymer and/or a propylene copolymer with up to 10 mol % of ethylene and/or one or more C 4 -C 8 α-olefins, the propylene polymer having an MFR≧80 g/10 min,
B) 10-23 parts per weight of an elastomeric ethylene-propylene copolymer having an intrinsic viscosity IV of ≦2.2 dl/g and an ethylene content of at least 80 mol %,
C) 5-15 parts per weight of an elastomeric ethylene-propylene copolymer having an intrinsic viscosity IV of 4.0-6.5 dl/g and an ethylene content of up to 70 mol %,
D) 3-10 parts per weight of an elastomeric ethylene-1-octene copolymer having an ethylene content of at least 80 mol % and having a melt index MI (190° C., 2.16 kg) of 3-50 g/10 min and
E) 5-15 parts per weight of inorganic filler,
melting and homogenizing and
cooling and palletizing the mixture.
11. An automobile interior or exterior part comprising a composition produced by the process of claim 1 or 2 .
12. An automobile interior or exterior part according to claim 11 , wherein the part is an automobile bumper or body part.