Reinforced rubber composition

Patent metadata

Field	Value
Publication number	US-12240979-B2
Application number	US-202217583632-A
Country	US
Kind code	B2
Filing date	Jan 25, 2022
Priority date	Jan 25, 2021
Publication date	Mar 4, 2025
Grant date	Mar 4, 2025

Abstract

A curable rubber composition including a rubber, a plurality of ground particles, and a reactive surfactant represented by the formula: X—Y—Z where X is a reactive group capable of forming covalent links with the rubber during compounding or vulcanization, Y is a hydrophobic linkage, and Z is a polar group capable of forming self-assemblies via intermolecular interactions, and wherein the reactive surfactant is incompatible with the rubber and a method of making the same.

First claim

What is claimed is:

1. A curable rubber composition comprising:
a vulcanizable rubber;
a plurality of ground vulcanized rubber particles;
a reactive surfactant represented by the formula:
X—Y—Z

where X is a reactive group, Y is a hydrophobic linkage, and Z is a polar group, and where the reactive group is capable of forming covalent links with the vulcanizable rubber during compounding or vulcanization and the polar group is capable of forming self-assemblies via intermolecular interactions; and wherein the reactive surfactant is incompatible with the vulcanizable rubber; and

wherein a ratio of the plurality of ground rubber particles to the reactive surfactant, by weight, is from 15:1 or greater.

2. The curable rubber composition of claim 1 , wherein the curable rubber composition includes at least 1 parts per hundred rubber of the plurality of ground vulcanized rubber particles.

3. The curable rubber composition of claim 1 , wherein the reactive group is selected from a sulfur-containing group.

4. The curable rubber composition of claim 3 , wherein the reactive group is a thiol group.

5. The curable rubber composition of claim 1 , wherein the hydrophobic linkage is a hydrocarbon chain.

6. The curable rubber composition of claim 4 , wherein the hydrocarbon chain includes between 2 and 30 carbon atoms.

7. The curable rubber composition of claim 1 , wherein the polar group includes at least one β-alanine unit.

8. The curable rubber composition of claim 7 , wherein the polar group includes two β-alanine units, wherein at least one of the two β-alanine units is terminated by a terminal alkyl chain.

9. The curable rubber composition of claim 1 , wherein the polar group includes a phosphate anion charge balanced by a cation with the general formula: —(RO)PO 3 − (1/n)cation n+ .

10. The curable rubber composition of claim 1 , wherein the polar group includes a sulfonate anion charge balanced by a cation with the general formula: —SO 3 − (1/n)cation n+ where n=1 or 2.

11. A curable rubber composition comprising:
a vulcanizable rubber;
a plurality of ground vulcanized rubber particles;
a reactive surfactant represented by the formula:
X—Y—Z

where X is a reactive group, Y is a hydrophobic linkage, and Z is a polar group, and where the reactive group is capable of forming covalent links with the vulcanizable rubber during compounding or vulcanization and the polar group is capable of forming self-assemblies via intermolecular interactions;
wherein the reactive surfactant is incompatible with the vulcanizable rubber; and
wherein the curable rubber composition includes between 0.5 parts per hundred rubber and 2.5 parts per hundred rubber of the reactive surfactant.

12. The curable rubber composition of claim 1 , wherein the curable rubber composition includes a ratio of the plurality of ground rubber particles to the reactive surfactant, by weight, of from 15:1 to 50:1.

13. The curable rubber composition of claim 1 , further comprising:
optionally one or more of antioxidants, antidegradants, additional fillers, oils, plasticizers, resins, waxes, and curatives.

14. The curable rubber composition of claim 1 , wherein the reactive surfactant is mixed directly with vulcanizable rubber and the plurality of ground vulcanized rubber particles.

15. A method of making a curable rubber composition that is prepared by a process comprising:
mixing a masterbatch comprising a vulcanizable rubber;
providing a plurality of ground vulcanized rubber particles and a reactive surfactant represented by the formula:
X—Y—Z

where X is a reactive group, Y is a hydrophobic linkage, and Z is a polar group, and where the reactive group is capable of forming covalent links with the vulcanizable rubber during compounding or vulcanization and the polar group is capable of forming self-assemblies via intermolecular interactions, and wherein the reactive surfactant is incompatible with the vulcanizable rubber;
wherein a ratio of the plurality of ground rubber particles to the reactive surfactant, by weight, is from 15:1 or greater; and
mixing to form a dispersed mixture, wherein the step of mixing to form the dispersed mixture takes place at a temperature greater than a melting point of the reactive surfactant.

16. The method of claim 15 , wherein mixing to form a dispersed mixture takes place at a temperature greater than a melting point of the reactive surfactant.

17. The method of claim 16 , wherein the reactive group is selected from a sulfur- containing group.

18. The method of claim 16 , wherein the hydrophobic linkage is a hydrocarbon chain.

19. The method of claim 16 , wherein the polar group includes at least one β-alanine unit.

Assignees

• Jia Li
• Sun Yu
• Univ Akron

Inventors

• Jia Li
• Sun Yu

Classifications

• C08K5/37

  Thiols · CPC title

• Y02W30/62

  Plastics recycling; Rubber recycling · 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

• C08L9/00 Primary

  Compositions of homopolymers or copolymers of conjugated diene hydrocarbons · CPC title

• C08K3/22

  of metals · CPC title