Propylene impact copolymer blends with improved gloss

Patent metadata

Field	Value
Publication number	US-10920053-B2
Application number	US-201816128861-A
Country	US
Kind code	B2
Filing date	Sep 12, 2018
Priority date	Oct 16, 2017
Publication date	Feb 16, 2021
Grant date	Feb 16, 2021

Abstract

Described herein are polymer blends comprising (a) a propylene impact copolymer comprising a polypropylene component present in a continuous phase and a first elastomeric component present in a disperse phase; and (b) a second elastomeric component, and the interfacial tension between the second elastomeric component and the impact copolymer is at least 1.2 mN/m. The polymer blends of present invention provides improved gloss and impact properties.

First claim

We claim:

1. A polymer blend comprising:
(a) a propylene impact copolymer comprising a polypropylene component present in a continuous phase and a first elastomeric component present in a disperse phase; and
(b) a second elastomeric component, wherein the second elastomeric component comprises a propylene-based elastomer containing 75 to 97 wt. % of propylene-derived units and from 3 to 25 wt. % of ethylene and/or C4-C20 α-olefin derived units and has an mm propylene triad tacticity of at least 75%, and a heat of fusion of less than 75 J/g;
wherein the interfacial tension between the second elastomeric component and the impact copolymer is at least 2.7 mN/m.

2. The polymer blend of claim 1 , wherein the interfacial tension is at least 4.5 mN/m.

3. The polymer blend of claim 1 comprising from 75 to 99 wt. % of the propylene impact copolymer and from 1 to 25 wt. % of the second elastomeric component based on the weight of the polymer blend.

4. The polymer blend of claim 1 comprising from 85 to 97 wt. % the propylene impact copolymer and from 3 to 15 wt. % the second elastomeric component based on the weight of the polymer blend.

5. The polymer blend of claim 1 , wherein the propylene impact copolymer comprises from 40 to 95 wt. % polypropylene homopolymer and from 5 to 60 wt. % an ethylene-propylene copolymer based on the weight of the propylene impact copolymer; and the ethylene-propylene copolymer comprises propylene-derived units and from 20 to 85 wt. % units derived from ethylene and/or C4 to C12 αolefins based on the weight of the ethylene-propylene copolymer.

6. The polymer blend of claim 1 , wherein the propylene impact copolymer comprises from 70 to 90 wt. % polypropylene homopolymer and from 10 to 30 wt. % an ethylene-propylene copolymer based on the weight of the propylene impact copolymer; and the ethylene-propylene copolymer comprises propylene-derived units and from 30 to 60 wt. % units derived from ethylene and/or C4 to C12 α-olefins based on the weight of the ethylene-propylene copolymer.

7. The polymer blend of claim 1 , wherein the propylene impact copolymer has an MFR at 190° C./2.16 kg of from 2.0 g/10 min to 10.0 g/10 min.

8. The polymer blend of claim 1 , wherein the propylene-based elastomer is a propylene-ethylene copolymer having a melt flow rate at 230° C./2.16 kg of at least 1.0 g/10 min.

9. The polymer blend of claim 8 , wherein the propylene-ethylene copolymer has the melt flow rate at 230° C./2.16 kg of from 10.0 to 50.0 g/10 min.

10. The polymer blend of claim 1 , wherein the second elastomeric component comprises an ethylene-based plastomer containing 65 to 95 wt. % ethylene-derived units and from 5 to 35 wt. % 1-butene, 1-hexene, and/or 1-octene derived units based on the weight of the ethylene-based plastomer.

11. The polymer blend of claim 1 , wherein at least a portion of the second elastomeric component is present in the continuous phase.

12. The polymer blend of claim 1 having a gloss at 60°, as measured according to method IS07668, of greater than 75.

13. The polymer blend of claim 1 having a gloss at 60°, as measured according to method IS07668, of greater than 85.

14. The polymer blend of claim 1 , wherein the polymer blend comprises dispersed particles of the first elastomeric component having a smaller average particle size than that of the propylene impact copolymer.

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Abubakar Saifudin M
• Peng Dan
• Yuan Li
• Stokes James P

Classifications

• C08L2207/02

  Heterophasic composition · CPC title

• C08L2205/025

  containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure · CPC title

• C08L2205/03

  containing three or more polymers in a blend · CPC title

• C08F2500/15

  Isotactic · CPC title

• C08F2500/16

  Syndiotactic · CPC title