Soft polypropylene composition

1. A heterophasic propylene copolymer (RAHECO), said heterophasic propylene copolymer (RAHECO) comprises a matrix (M) being a random propylene copolymer (R-PP) and an elastomeric propylene copolymer (E) dispersed in said matrix (M),

wherein the heterophasic propylene copolymer (RAHECO) has

a) a melt flow rate MFR 2 (230° C./2.16 kg) measured according to ISO 1133 in the range of 2.5 to 12.0 g/10 min,

b) a xylene cold soluble fraction (XCS) determined according ISO 16152 (25° C.) in the range of 38.0 to 50.0 wt.-%, said xylene cold soluble fraction (XCS) having a comonomer content below 36.0 mol-%,

and wherein further

the xylene cold insoluble fraction (XCI) of the heterophasic propylene copolymer (RAHECO) has a relative content of isolated to block ethylene sequences (I(E)) of below 55.0%, wherein the I(E) content is defined by equation (I)

I

⁡

(

E

)

=

fPEP

(

fEEE

+

fPEE

+

fPEP

)

×

100

(

I

)

wherein

I(E) is the relative content of isolated to block ethylene sequences [in %];

fPEP is the mol fraction of propylene/ethylene/propylene sequences (PEP) in the xylene cold insoluble fraction (XCI) of the heterophasic propylene copolymer (RAHECO);

fPEE is the mol fraction of propylene/ethylene/ethylene sequences (PEE) and of ethylene/ethylene/propylene sequences (EEP) in the xylene cold insoluble fraction (XCI) of the heterophasic propylene copolymer (RAHECO); and

fEEE is the mol fraction of ethylene/ethylene/ethylene sequences (EEE) in the xylene cold insoluble fraction (XCI) of the heterophasic propylene copolymer (RAHECO),

wherein all sequence concentrations being based on a statistical triad analysis of 13 C-NMR data.

2. The heterophasic propylene copolymer (RAHECO) according to claim 1 , wherein the heterophasic propylene copolymer (RAHECO) is free of phthalic acid esters and their respective decomposition products.

3. The heterophasic propylene copolymer (RAHECO) according to claim 1 , wherein the xylene cold soluble fraction (XCS) has an intrinsic viscosity (IV) determined according to DIN ISO 162/1 (in Decalin at 135° C.) in the range of 1.8 to 3.5 dl/g.

4. The heterophasic propylene copolymer (RAHECO) according to claim 1 , wherein the random propylene copolymer (R-PP) has at least one of:

i) before vis-breaking a melt flow rate MFR 2 (230° C./2.16 kg) measured according to ISO 1133 in the range of 1.0 to 4.0 g/10 min, or

ii) a comonomer content in the range of 5.1 to 17.0 mol-%.

5. The heterophasic propylene copolymer (RAHECO) according to claim 1 , wherein the random propylene copolymer (R-PP) comprises a first propylene copolymer fraction (R-PP1) and a second propylene copolymer fraction (R-PP2) and the comonomer contents of the random propylene copolymer (R-PP) and the first propylene copolymer fraction (R-PP1) fulfil inequation (III),

Co

⁡

(

RPP

)

Co

⁡

(

RPP

⁢

⁢

1

)

≥

2.0

,

(

III

)

wherein Co(RPP) is the comonomer content of the random propylene copolymer (R-PP) and Co(RPP1) is the comonomer content of the first propylene copolymer fraction (R-PP1).

6. The heterophasic propylene copolymer (RAHECO) according to claim 1 , wherein the heterophasic propylene copolymer (RAHECO) comprises 60.0 to 85.0 wt.-%, based on the total weight of the heterophasic propylene copolymer (RAHECO), of the random propylene copolymer (R-PP) and 15.0 to 40.0 wt.-%, based on the total weight of the heterophasic propylene copolymer (RAHECO), of the elastomeric propylene copolymer (E).

7. The heterophasic propylene copolymer (RAHECO) according to claim 1 , wherein the comonomers of at least one of: the random propylene copolymer (R-PP) or the elastomeric propylene copolymer (E) are at least one of: ethylene or C 4 to C 8 α-olefins.

8. The heterophasic propylene copolymer (RAHECO) according to claim 1 , wherein the heterophasic propylene copolymer (RAHECO) has been visbroken.

9. The heterophasic propylene copolymer (RAHECO) according to claim 8 , wherein the heterophasic propylene copolymer (RAHECO) has been visbroken with a visbreaking ratio (VR) as defined by in-equation (II)

1.1

≤

MFRfinal

-

MFRinitial

MFRinitial

≤

10.0

(

II

)

wherein

“MFRfinal” is the MFR 2 (230° C./2.16 kg) of the heterophasic propylene copolymer (RAHECO) after visbreaking and

“MFRinitial” is the MFR 2 (230° C./2.16 kg) of the heterophasic propylene copolymer (RAHECO) before visbreaking.

10. The heterophasic propylene copolymer (RAHECO) according to claim 1 , wherein the heterophasic propylene copolymer (RAHECO) has a flexural modulus measured according to ISO 178 on injection molded specimen below 500 MPa.

11. The heterophasic propylene copolymer (RAHECO) according to claim 1 , wherein the heterophasic propylene copolymer (RAHECO) has at least one of:

i) a haze according to ASTM D 1003-00 measured on a 1 mm thick injection molded specimen below 80.0%, preferably below 78%, or

ii) a haze before sterilization determined according to ASTM D 1003-00 measured on a 50 μm cast film of below 15.0%, preferably of below 12.0%, or

iii) a haze after sterilization determined according to ASTM D 1003-00 measured on a 50 μm cast film of below 20.0%, preferably of below 16.0%.

12. The heterophasic propylene copolymer (RAHECO) according to claim 1 , wherein the heterophasic propylene copolymer (RAHECO) has a melting temperature Tm of at least 140° C.

13. A polymerization process for producing the heterophasic propylene copolymer (RAHECO) according to claim 1 , comprising the steps of

a) polymerizing in a first reactor (R1) propylene and at least one of: ethylene or a C 4 to C 8 α-olefin, obtaining a first random propylene copolymer fraction (R-PP1),

b) transferring the first random propylene copolymer fraction (R-PP1) into a second reactor (R2),

c) polymerizing in said second reactor (R2) in the presence of the first random propylene copolymer fraction (R-PP1) propylene and at least one of: ethylene or a C 4 to C 8 α-olefin, obtaining a second random copolymer fraction (R-PP2), said first random propylene copolymer fraction (R-PP1) and said second random copolymer fraction (R-PP2) forming the random propylene copolymer (R-PP),

d) transferring said random propylene copolymer (R-PP) into a third reactor (R3), and

e) polymerizing in said third reactor (R3) in the presence of at least one of: the random propylene copolymer (R-PP) propylene or a C 4 to C 8 α-olefin, obtaining a third polymer fraction, said polymer fraction is the elastomeric copolymer (E), said propylene copolymer (R-PP) and said elastomeric propylene copolymer (E) form the heterophasic propylene copolymer (RAHECO).

14. The process according to claim 13 , wherein the first random propylene copolymer fraction (R-PP1), the random propylene copolymer (R-PP) and the elastomeric copolymer (E) have been polymerized in the presence of

a) a Ziegler-Natta catalyst (ZN-C) comprising compounds (TC) of a transition metal of Group 4 to 6 of IUPAC, a Group 2 metal compound (MC) and an internal donor (ID), wherein said internal donor (ID) is a non-phthalic compound, preferably is a non phthalic acid ester;

b) optionally a co-catalyst (Co), and

c) optionally an external donor (ED).

15. The process according to claim 13 , wherein

a) the internal donor (ID) is selected from optionally substituted malonates, maleates, succinates, glutarates, cyclohexene-1,2-dicarboxylates, benzoates, derivatives thereof, and mixtures thereof, preferably the internal donor (ID) is a citraconate;

b) the molar-ratio of co-catalyst (Co) to external donor (ED) [Co/ED] is 5 to 45.

16. A film, comprising the heterophasic propylene copolymer (RAHECO) according to claim 1 .

17. A cable insulation, comprising the heterophasic propylene copolymer (RAHECO) according to claim 1 .