THERMOPLASTIC COMPOSITION

• US 20190315955A1
• Filed: 06/21/2019
• Published: 10/17/2019
• Est. Priority Date: 12/23/2016
• Status: Active Grant

• Current Assignee: SABIC Global Technologies BV (Government of Saudi Arabia)
• Original Assignee: SABIC Global Technologies BV (Government of Saudi Arabia)
• Inventors: Valkier, Pieter, Van Beek, Dimphna Johanna Maria, Biemond, Gerard Jan Eduard, Donners, Rob
• Granted Patent: US 11,091,620 B2
• Time in Patent Office: Days
• CPC Class Codes: C08K 3/34 Silicon-containing compounds
• CPC Class Codes: C08L 2205/025 containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
• CPC Class Codes: C08L 2205/03 containing three or more polymers in a blend
• CPC Class Codes: C08L 2205/035 containing four or more polymers in a blend
• CPC Class Codes: C08L 2207/02 Heterophasic composition
• CPC Class Codes: C08L 23/02 not modified by chemical after-treatment
• CPC Class Codes: C08L 23/04 Homopolymers or copolymers of ethene
• CPC Class Codes: C08L 23/12 Polypropene
• CPC Class Codes: C08L 23/16 Elastomeric ethene-propene or ethene-propene-diene copolymers, e.g. EPR and EPDM rubbers

Abstract

The present invention relates to a thermoplastic composition, e.g., for automotive parts, comprising: (A) from 10 to 69 wt. % polypropylene(s); (B) at least 30 wt. % heterophasic propylene copolymer comprising: from 70 to 92 wt. % a propylene-based matrix consisting of a polypropylene, wherein the propylene polymer has an intrinsic viscosity IV_PP; from 8 to 30 wt. % dispersed ethylene-α-olefin copolymer having an ethylene content of between 10 and 55 wt and an intrinsic viscosity IV_EPR; and wherein the ratio of IV_EPR/IV_PP is between 3 and 7; C) from 0-30 wt. % ethylene-α-olefin elastomer comprising ethylene and a C3 to C10 α-olefin; D) from 1 up to 30 wt. % talc as a filler; E) from 0-10 wt. % high-density polyethylene (HDPE); and F) from 0-3 wt. % additional additives.

Claims

1. A thermoplastic composition comprising:

(A) from 10 to 69 wt. %, based on the weight of said composition polypropylene;

(B) at least 30 wt. %, based on the weight of said composition of a heterophasic propylene copolymer comprising;

from 70 to 92 wt. % based on the weight of said heterophasic propylene copolymer of a propylene-based matrix consisting of a polypropylene polymer;

wherein the polypropylene polymer has an intrinsic viscosity IV_PP;

from 8 to 30 wt. % based on the weight of said heterophasic propylene copolymer of a dispersed ethylene-α

-olefin copolymer having an ethylene content of between 10 and 55 wt. % based on the weight of the ethylene-α

-olefin copolymer and wherein the ethylene-α

-olefin copolymer has an intrinsic viscosity IV_EPR; and

wherein the ratio of IV_EPR/IV_PP is between 3 and 7, wherein IV_PP and IV_EPR are determined according to ISO-1628-1 (2009) and ISO-1628-3 (2010) based on the amount of the xylene-soluble matter (CXS) and xylene-insoluble matter (CXI) measured according to ISO 16152 (2005);

C) from 0-30 wt. %, based on the weight of said composition of an ethylene-α

-olefin elastomer comprising ethylene and a C3 to C10 α

-olefin;

D) from 1-30 wt. %, based on the weight of said composition of a talc;

E) from 0-10 wt. % based on the weight of said composition of a high-density polyethylene (HDPE);

F) from 0-5 wt. %, based on the weight of said composition of an additive.

2. The composition according to claim 1, wherein said composition comprises as the polypropylene according to A) a heterophasic propylene copolymer consisting of

i) a propylene-based matrix consisting of a propylene homopolymer and/or a propylene-α

-olefin copolymer, said propylene-α

-olefin copolymer consisting of at least 70 wt. %, of propylene and at most 30 wt. %, of α

-olefin, based on the total weight of the propylene-α

-olefin copolymer, and

ii) a dispersed ethylene-α

-olefin copolymer comprising ethylene and a C3 to C10 α

-olefin.

3. The composition according to claim 1, wherein said composition comprises as the polypropylene according to A) a heterophasic propylene copolymer A-A consisting of:

from 70 to 90 wt. % based on the weight of the heterophasic propylene copolymer A-A of a polypropylene-based matrix consisting of a polypropylene having a melt flow index of from 55 to 85 g/10 min as measured according to ISO 1133 (2005) (2.16 kg and 230°

C.); and

from 10 to 45 wt. % based on the weight of the heterophasic propylene copolymer A-A of a dispersed-ethylene-α

-olefin copolymer having a melt flow index of from 2.5 to 5.0 g/10 min as measured according to ISO 1133 (2005) (2.16 kg and 230°

C.);

wherein the sum of the polypropylene-based matrix and the dispersed ethylene-α

-olefin copolymer is 100 wt. %.

4. The composition according to claim 1, wherein said composition comprises as the polypropylene according to A) a heterophasic propylene copolymer A-B consisting of:

from 60 to 85 wt. % based on the weight of the heterophasic propylene copolymer A-B of a polypropylene-based matrix consisting of a polypropylene having a melt flow index of from 50 to 100 g/10 min as measured according to ISO 1133 (2005) (2.16 kg and 230°

C.); and

from 15 to 40 wt. % based on the weight of the heterophasic propylene copolymer A-B of a dispersed ethylene-α

-olefin copolymer having a melt flow index of from 0.050 to 0.30 g/10 min as measured according to ISO 1133 (2005) (2.16 kg and 230°

C.);

wherein the sum of the polypropylene-based matrix and the dispersed ethylene-α

-olefin copolymer is 100 wt. %.

5. The composition according to claim 1, wherein said composition comprises as a polypropylene according to A):

a heterophasic propylene copolymer A-A consisting of from 70 to 90 wt. % based on the weight of the heterophasic propylene copolymer A-A of a polypropylene-based matrix consisting of a polypropylene having a melt flow index of from 55 to 85 g/10 min as measured according to ISO 1133 (2005) (2.16 kg and 230°

C.); and

from 10 to 45 wt. % based on the weight of the heterophasic propylene copolymer A-A of a dispersed-ethylene-α

-olefin copolymer having a melt flow index of from 2.5 to 5.0 g/10 min as measured according to ISO 1133 (2005) (2.16 kg and 230°

C.);

wherein the sum of the polypropylene-based matrix and the dispersed ethylene-α

-olefin copolymer is 100 wt. %; and

a heterophasic propylene copolymer A-B consisting of from 60 to 85 wt. % based on the weight of the heterophasic propylene copolymer A-B of a polypropylene-based matrix consisting of a polypropylene having a melt flow index of from 50 to 100 g/10 min as measured according to ISO 1133 (2005) (2.16 kg and 230°

C.); and

from 15 to 40 wt. % based on the weight of the heterophasic propylene copolymer A-B of a dispersed ethylene-α

-olefin copolymer having a melt flow index of from 0.050 to 0.30 g/10 min as measured according to ISO 1133 (2005) (2.16 kg and 230°

C.);

wherein the sum of the polypropylene-based matrix and the dispersed ethylene-α

-olefin copolymer is 100 wt. %;

wherein a weight ratio of the heterophasic propylene copolymer A-A to the heterophasic propylene copolymer A-B is between 1;

1 and 10;

1.

6. The composition according to claim 1, wherein said composition comprises as the polypropylene according to A) a heterophasic propylene copolymer A-C having a melt flow rate of at least 40 g/10 min as determined in accordance with ISO 1133 (2005) (230°

C., 2.16 kg) and a FOG value of at most 500 μ

g/g, as determined by VDA 278 (2011).

7. The composition according to claim 1, wherein the composition has a melt flow index between 5 and 70, as determined in accordance with ISO 1133 (2005) (2.16 kg, 230°

C.).

8. The composition according to claim 1, wherein the composition has a tensile modulus as measured in accordance with ISO 527-2(1A) (2012) at 23°

C. of at least 1150 MPa.

9. The composition according to claim 1, wherein the combined amount of the polypropylene of component (A) and the heterophasic propylene copolymer of component (B) is at least 80 wt. % based on the weight of said composition.

10. The composition according to claim 1, wherein the composition has a flexural modulus measured according to ISO 178 (2010) at 23°

C. of at least 1200 MPa.

11. The composition according to claim 1, comprising as the polypropylene according to A) a heterophasic propylene copolymer.

12. The composition according to claim 1, comprising as the polypropylene according to A) more than one heterophasic propylene copolymer.

13. The composition according to claim 1, wherein the ratio of IV_EPR/IV_PP is between 3 and 5.

14. An automotive part comprising the composition according to claim 1.

15. The automotive part according to claim 14, having a tiger stripe value of at least 6.5, wherein the tiger stripe value is measured according to the procedure wherein, after molding, each of the specimens is visually observed for occurrence of tiger stripes on its smooth side and textured side, and the quality of the surface is evaluated on a scale of 1 to 10, with 10 being the best.

16. The automotive part according to claim 15, wherein the tiger stripe value is at least 7.

17. The automotive part according to claim 14, said part being selected from the group consisted of a bumper fascia, a cowl top, an instrument panel, a pillar trim and a door panel.

18. A method for the manufacture of the automotive part of claim 14 comprising injection molding the composition.