Articles comprising propylene-based elastomers

• US 20050107529A1
• Filed: 11/12/2004
• Published: 05/19/2005
• Est. Priority Date: 11/14/2003
• Status: Active Grant

• Current Assignee: ExxonMobil Chemical Patents Inc. (Exxon Mobil Corporation)
• Original Assignee: ExxonMobil Chemical Patents Inc. (Exxon Mobil Corporation)
• Inventors: Sahnoune, Abdelhadi, Datta, Sudhin, Cheng, Chia Yung, Srinivas, Srivatsan
• Granted Patent: US 8,013,093 B2
• Time in Patent Office: Days
• US Class Current: 525/70
• CPC Class Codes: A43B 13/04 Plastics, rubber or vulcanised fibre
• CPC Class Codes: C08F 210/06 Propene
• CPC Class Codes: C08F 210/18 with non-conjugated dienes, e.g. EPT rubbers
• CPC Class Codes: C08F 236/20 unconjugated
• CPC Class Codes: C08F 2500/11 Melt tension or melt strength
• CPC Class Codes: C08F 2500/15 Isotactic
• CPC Class Codes: C08F 2500/17 Viscosity
• CPC Class Codes: C08F 2500/20 Activation energy or enthalpy
• CPC Class Codes: C08F 2500/21 Rubbery or elastomeric properties
• CPC Class Codes: C08F 2500/25 Cycloolefine
• CPC Class Codes: C08F 2500/26 Use as polymer for film forming
• CPC Class Codes: C08F 4/65908 in combination with an ionising compound other than alumoxane, e.g. (C6F5)4B-X+
• CPC Class Codes: C08F 4/65927 two cyclopentadienyl rings being mutually bridged
• CPC Class Codes: D01D 5/0985 by means of a flowing gas (e.g. melt-blowing)
• CPC Class Codes: D01F 6/46 of polyolefins
• CPC Class Codes: Y10T 442/678 Olefin polymer or copolymer sheet or film [e.g., polypropylene, polyethylene, ethylene-butylene copolymer, etc.]

Abstract

The present invention is directed generally to the use of propylene-based elastomers in articles. The propylene-based elastomers have isotactic polypropylene crystallinity, a melting point by DSC of 110° C. or less, a heat of fusion of from 5 to 50 J/g, and comprise at least 75 wt % propylene-derived units, at least 6 wt % ethylene-derived units, and optionally diene-derived units. The present invention is also directed to processes for making articles comprising propylene-based elastomers.

Claims

1. An article comprising:

at least 60 wt %, based on the total polymeric weight of the article, of an elastomer having an isotactic propylene triad tacticity of from 65 to 95%, a melting point by DSC equal to or less than 110°

C., a heat of fusion of from 5 to 50 J/g, and comprising;

(a) propylene-derived units in an amount of at least 75 wt %, based on the combined weight of components (a), (b), and (c),

(b) ethylene-derived units in an amount of at least 6 wt %, based on the combined weight of components (a), (b), and (c), and

(c) optionally 10 wt % or less of diene-derived units, based on the combined weight of components (a), (b), and (c);

wherein the article is at least partially cured.

2. The article of claim 1, wherein the article is a fabric.

3. The article of claim 1, wherein the article is a film.

4. The article of claim 1, wherein the diene-derived units are present in the elastomer in an amount within the range of from 0.3 to 5 wt %, based on the combined weight of components (a), (b), and (c).

5. The article of claim 1, wherein the article further comprises a fluid curing system.

6. The article of claim 4, wherein the article further comprises a fluid curing system.

7. The article of claim 5, wherein the fluid curing system comprises peroxide.

8. The article of claim 1, further comprising at least 10 wt %, based on the total polymeric weight of the article, of a crystalline polymer component selected from the group consisting of propylene homopolymers, propylene graft copolymers, propylene block copolymers, propylene random copolymers, and mixtures thereof, and having a melting point by DSC of 115°

C. or higher, a heat of fusion of 50 J/g or higher, wherein the crystalline polymer is dispersed in a continuous phase formed by the elastomer.

9. The article of claim 1, wherein the article is at least partially cured by radiation.

10. An article comprising:

(a) at least 60 wt %, based on the total polymeric weight of the article, of an elastomer having an isotactic propylene triad tacticity of from 65 to 95%, a melting point by DSC equal to or less than 110°

C., a heat of fusion of from 5 to 50 J/g, and comprising;

(i) propylene-derived units in an amount of at least 75 wt %, based on the combined weight of components (i), (ii), and (iii),

(ii) ethylene-derived units in an amount of at least 6 wt %, based on the combined weight of components (i), (ii), and (iii), and

(iii) optionally 10 wt % or less of diene-derived units, based on the combined weight of components (i), (ii), and (iii); and

(b) at least 10 wt %, based on the total polymeric weight of the article, of a crystalline polymer component selected from the group consisting of propylene homopolymers, propylene graft copolymers, propylene block copolymers, propylene random copolymers, and mixtures thereof, and having a melting point by DSC of 115°

C. or higher, a heat of fusion of 50 J/g or higher, wherein the crystalline polymer is dispersed in a continuous phase formed by the elastomer;

wherein the article is at least partially cured.

11. The article of claim 10, wherein the article is a fabric.

12. The article of claim 10, wherein the article is a film.

13. The article of claim 10, wherein the diene-derived units are present in the elastomer in an amount within the range of from 0.3 to 5 wt %, based on the combined weight of components (a), (b), and (c).

14. The article of claim 10, wherein the article further comprises a fluid curing system.

15. The article of claim 13, wherein the article further comprises a fluid curing system.

16. The article of claim 14, wherein the fluid curing system comprises peroxide.

17. The article of claim 10, wherein the article is at least partially cured by radiation.

18. A process for making an article, the process comprising:

(a) extruding a composition comprising an elastomer to produce an article, the elastomer having an isotactic propylene triad tacticity of from 65 to 95%, a melting point by DSC equal to or less than 110°

C., a heat of fusion of from 5 to 50 J/g, and comprising;

(i) propylene-derived units in an amount of at least 75 wt %, based on the combined weight of components (i), (ii), and (iii),

(ii) ethylene-derived units in an amount of at least 6 wt %, based on the combined weight of components (i), (ii), and (iii), and

(iii) optionally diene-derived units in an amount within the range of from 0.1 to 10 wt %, based on the combined weight of components (i), (ii), and (iii); and

(b) curing the article.

19. The process of claim 18, wherein the curing step is subsequent to the extruding step.

20. The process of claim 18, wherein the article is a film.

21. The process of claim 18, wherein the article is a fabric.