Rubber compositions with reduced graphene oxide

Patent metadata

Field	Value
Publication number	US-11518856-B2
Application number	US-201816958631-A
Country	US
Kind code	B2
Filing date	Dec 20, 2018
Priority date	Dec 27, 2017
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

Rubber components of a tire comprising a diene elastomer and at least 1 phr of reduced graphene oxide nanoparticles having a specific surface area of at least 700 m2/g, an oxygen content of no more than 6 at %, and a ratio of non-aromaticity to aromaticity ID/IG of at least 0.7 as determined by Raman spectroscopy. Methods of preparing such rubber compositions in an internal mixer for achieving good distribution and dispersion are also included.

First claim

What is claimed is:

1. A method of preparing a rubber composition for an article, comprising:
placing a diene elastomer within a mixing chamber of an internal mixer;
mixing the diene elastomer until it reaches a first predetermined temperature;
adding a portion of reduced graphene oxide to the mixing chamber and mixing the diene elastomer and particles of the reduced graphene oxide in the mixing chamber to form a mixture with the reduced graphene oxide particles incorporated into the mixture, wherein the reduced graphene oxide has a specific surface area that is at least 700 m 2 /g, has an oxygen content of no more than 8 at %, and a ratio of non-aromaticity to aromaticity I D /IG of at least 0.7 as determined by Raman spectroscopy;
repeating adding a portion of a reduced graphene oxide to the mixing chamber and mixing the diene elastomer and the particles of the reduced graphene oxide in the mixing chamber to form a mixture with the reduced graphene oxide incorporated into the mixture, repeating as many times as necessary until a desired amount of the reduced graphene oxide has been added to the mixing chamber;
heating the mixture by work performed by the internal mixer until it reaches a second predetermined temperature;
dropping the mixture from the internal mixer; and
cooling the mixture to form a cooled mixture.

2. The method of claim 1 , wherein the cooled mixture is a master batch, further comprising:
placing the master batch into a mixing chamber of an internal mixer.

3. The method of claim 2 , further comprising:
adding additional components into the mixing chamber; and
mixing the additional components into the mixture.

4. The method of claim 3 , further comprising:
adding a secondary filler to the mixer, wherein no more than 20% of the secondary filler is added until the desired amount of the reduced graphene oxide has been added to the mixing chamber.

5. The method of claim 4 , wherein none of the secondary filler is added until the desired amount of the reduced graphene oxide has been added to the mixing chamber.

6. The method of claim 5 , further comprising:
mixing a curing agent into the cooled mixture.

7. The method of claim 6 , further comprising:
forming the article from the rubber composition; and
curing the article.

8. The method of claim 7 , wherein the step of forming the article further comprises:
extruding the article.

9. The method of claim 1 , further comprising:
adding a secondary filler to the mixer, wherein no more than 20% of the secondary filler is added until the desired amount of the reduced graphene oxide has been added to the mixing chamber.

10. The method of claim 9 , wherein none of the secondary filler is added until the desired amount of the reduced graphene oxide has been added to the mixing chamber.

11. The method of claim 1 , further comprising:
mixing a curing agent into the cooled mixture.

12. The method of claim 1 , further comprising:
forming the article from the rubber composition; and
curing the article.

13. The method of claim 12 , wherein the step of forming the article further comprises:
extruding the article.

14. The method of claim 1 , wherein the stacked platelets are stacked with no more than 5 platelets per stack.

15. The method of claim 14 , wherein the stacked platelets are stacked with no more than 3 platelets per stack.

16. The method of claim 1 , wherein the oxygen content of the reduced graphene oxide particles is no more than 1 at %.

17. The method of claim 1 , wherein the reduced graphene oxide particles were reduced.

18. The method of claim 1 , wherein the diene rubber is a highly unsaturated diene rubber having a content of diene origins (conjugated diene) that is greater than 50 mol %.

19. The method of claim 18 , wherein the diene rubber is selected from the group consisting of natural rubber (NR), polyisoprene rubber (IR), polybutadiene rubber (BR), styrene-polybutadiene copolymer (SBR) and combinations thereof.

20. The method of claim 1 , wherein the article is a tire component.

Assignees

• Michelin & Cie
• Vautard Frederic

Inventors

• Vautard Frederic

Classifications

• C08J3/226 Primary

  using a polymer as a carrier · CPC title

• C08L9/06

  Copolymers with styrene · CPC title

• C08K2201/006

  Additives being defined by their surface area · CPC title

• C08L7/00

  Compositions of natural rubber · CPC title

• C08K3/36

  Silica · CPC title