Modified natural rubber, rubber composition using the rubber, and pneumatic tire using the composition

Patent metadata

Field	Value
Publication number	US-11655357-B2
Application number	US-202017102745-A
Country	US
Kind code	B2
Filing date	Nov 24, 2020
Priority date	Dec 13, 2019
Publication date	May 23, 2023
Grant date	May 23, 2023

Abstract

A modified natural rubber has a branching degree of 0.40 to 0.70 and includes a linking structure represented by formula (C), the linking structure having been formed by allowing polyisoprene, having a structure represented by formula (A) and/or formula (B), to bind in the structure to an amino compound having two or more primary amino groups:

wherein X represents a hydrogen atom or a methyl group, and Ps, which may be the same or different from each other, represent a polyisoprene unit;

W-(Q) m   (C)

wherein W represents a residue obtained by removing amino end groups from the amino compound Q represents at least one selected from the group consisting of the following general formulae (Q-1) to (Q-4), and m represents 2 to 4;

wherein * 1 indicates binding to a carbon atom of a polyisoprene unit, and * 2 indicates binding to a carbon atom of the residue represented by W.

First claim

What is claimed is:

1. A modified natural rubber having a branching degree of 0.40 to 0.70 and comprising a linking structure represented by the following general formula (C), the linking structure having been formed by allowing polyisoprene, having a structure represented by the following general formula (A) and/or general formula (B), to bind in the structure to an amino group of an amino compound having two or more primary amino groups:

wherein X represents a hydrogen atom or a methyl group, and Ps, which may be the same or different from each other, represent a polyisoprene unit;
W-(Q) m   (C)

wherein W represents a residue obtained by removing amino end groups from the amino compound Q represents at least one selected from the group consisting of the following general formulae (Q-1) to (Q-4), and m represents 2 to 4;

wherein * 1 indicates binding to a carbon atom of a polyisoprene unit, and * 2 indicates binding to a carbon atom of the residue represented by W.

2. The modified natural rubber according to claim 1 , wherein the polyisoprene has an absolute molecular weight of 200,000 to 600,000, and the modified natural rubber has an absolute molecular weight of 1,000,000 to 3,000,000.

3. The modified natural rubber according to claim 2 , wherein the amino compound comprises an amino compound having three or more primary amino group.

4. A rubber composition comprising 5 to 50 parts by mass of the modified natural rubber according to claim 3 in 100 parts by mass of a rubber component.

5. The modified natural rubber according to claim 3 , wherein the amino compound comprises tris(2-aminoethyl)amine.

6. A rubber composition comprising 5 to 50 parts by mass of the modified natural rubber according to claim 5 in 100 parts by mass of a rubber component.

7. The modified natural rubber according to claim 2 , wherein the amino compound comprises tris(2-aminoethyl)amine.

8. A rubber composition comprising 5 to 50 parts by mass of the modified natural rubber according to claim 7 in 100 parts by mass of a rubber component.

9. A rubber composition comprising 5 to 50 parts by mass of the modified natural rubber according to claim 2 in 100 parts by mass of a rubber component.

10. The modified natural rubber according to claim 1 , wherein the amino compound comprises an amino compound having three or more primary amino groups.

11. A rubber composition comprising 5 to 50 parts by mass of the modified natural rubber according to claim 10 in 100 parts by mass of a rubber component.

12. The modified natural rubber according to claim 10 , wherein the amino compound comprises tris(2-aminoethyl)amine.

13. A rubber composition comprising 5 to 50 parts by mass of the modified natural rubber according to claim 12 in 100 parts by mass of a rubber component.

14. The modified natural rubber according to claim 1 , wherein the amino compound comprises tris(2-aminoethyl)amine.

15. A rubber composition comprising 5 to 50 parts by mass of the modified natural rubber according to claim 14 in 100 parts by mass of a rubber component.

16. A rubber composition composing 5 to 50 parts by mass of the modified natural rubber according to claim 1 in 100 parts by mass of a rubber component.

17. A pneumatic tire produced using the rubber composition according to claim 16 .

Assignees

• Toyo Tire Corp

Inventors

• Nakashima Daiki

Classifications

• C08F136/08

  Isoprene · CPC title

• B60C1/00

  Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition · CPC title

• C08L7/00

  Compositions of natural rubber · CPC title

• C08C19/04 Primary

  Oxidation · CPC title

• C08L15/00 Primary

  Compositions of rubber derivatives (C08L11/00, C08L13/00 take precedence) · CPC title