Soft polypropylene composition

Patent metadata

Field	Value
Publication number	US-10519306-B2
Application number	US-201716095599-A
Country	US
Kind code	B2
Filing date	May 16, 2017
Priority date	May 18, 2016
Publication date	Dec 31, 2019
Grant date	Dec 31, 2019

Abstract

The present invention is directed to a new heterophasic propylene copolymer (RAHECO), a process for obtaining said heterophasic propylene copolymer (RAHECO) and a film or a cable insulation comprising the heterophasic propylene copolymer (RAHECO).

First claim

What is claimed is:

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:

Assignees

• Borealis Ag

Inventors

• Wang Jingbo
• Gitsas Antonios
• Leskinen Pauli
• Lilja Johanna
• Sandholzer Martina
• Gahleitner Markus

Classifications

• C08L2203/202

  use in electrical wires or wirecoating · CPC title

• C08L23/142 Primary

  at least partially crystalline copolymers of propene with other olefins · CPC title

• C08L23/16 Primary

  Ethylene-propylene or ethylene-propylene-diene copolymers · CPC title

• C08J5/18

  Manufacture of films or sheets · CPC title

• C08J2423/16

  Ethene-propene or ethene-propene-diene copolymers · CPC title