Styrene-butadiene rubber compound and rubber composition for tire bead fillers comprising the same

• US 10,654,994 B1
• Filed: 12/28/2016
• Issued: 05/19/2020
• Est. Priority Date: 11/10/2016
• Status: Active Grant

• Current Assignee: LG Chem Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Lee, Se Eun, Kim, Byoung Yun, Jo, In Sung, Lee, Jae Min, Choi, Woo Seok
• Primary Examiner(s): Nutter, Nathan M
• Application Number:
  US15/761,329
• Publication Number:
  US 20200131345A1
• Time in Patent Office: 1,238 Days
• CPC Class Codes: B60C 1/00 Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition
• CPC Class Codes: B60C 15/06 Flipper strips, fillers, or chafing strips and reinforcing layers for the construction of the bead
• CPC Class Codes: B60C 2001/0058 Compositions of the bead apexes
• CPC Class Codes: C08F 2/24 with the aid of emulsifying agents
• CPC Class Codes: C08F 212/08 Styrene
• CPC Class Codes: C08F 236/10 with vinyl-aromatic monomers
• CPC Class Codes: C08K 3/04 Carbon
• CPC Class Codes: C08K 3/36 Silica
• CPC Class Codes: C08L 2205/02 containing two or more polymers of the same C08L -group
• CPC Class Codes: C08L 2205/025 containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
• CPC Class Codes: C08L 9/06 Copolymers with styrene
• CPC Class Codes: C08L 9/08 Latex

Abstract

The present invention relates to a styrene-butadiene rubber compound and a rubber composition for tire bead fillers including the same, and more particularly, to a styrene-butadiene rubber compound capable of improving stiffness and hardness even when styrene-butadiene rubbers having different styrene contents are used instead of a combination of a conventional natural rubber and a phenol-based resin, and a rubber composition for tire bead fillers including the same.

Claims

1. A styrene-butadiene rubber compound comprising:

a) a first styrene-butadiene rubber having a styrene content of 60 to 95% by weight, a particle size of 100 to 200 nm, and a Mooney viscosity difference (Δ

MV) of 3 to 7 before/after blending; and

b) a second styrene-butadiene rubber having a styrene content of 5 to 10% by weight.

2. The styrene-butadiene rubber compound of claim 1, wherein the rubber compound comprises 75 to 99.5% by weight of the first styrene-butadiene rubber and 0.5 to 25% by weight of the second styrene-butadiene rubber.

3. The styrene-butadiene rubber compound of claim 1, wherein the styrene-butadiene rubber compound has a total styrene content of 23±

2% by weight and a Mooney viscosity (ML₍₁₊₄₎/100°

C.) of 46±

3.

4. The styrene-butadiene rubber compound of claim 1, wherein the first styrene-butadiene rubber has a weight average molecular weight of 1,000 g/mol to 2,000,000 g/mol.

5. The styrene-butadiene rubber compound of claim 1, wherein the second styrene-butadiene rubber has a weight average molecular weight of 1,000 g/mol to 2,000,000 g/mol.

6. The styrene-butadiene rubber compound of claim 1, wherein the first styrene-butadiene rubber and the second styrene-butadiene rubber are manufactured by emulsion polymerization.

7. The styrene-butadiene rubber compound of claim 1, wherein the second styrene-butadiene rubber is manufactured using an aliphatic organic acid and a sulfonate-based compound as emulsifying agents.

8. A rubber composition for tire bead fillers comprising a rubber, a reinforcing agent, and an additive,

wherein the rubber comprises the styrene-butadiene rubber compound defined claim 1.

9. The rubber composition of claim 8, wherein the reinforcing agent comprises carbon black and silica.

10. The rubber composition of claim 8, wherein the additive comprises one or more selected from the group consisting of a vulcanizing agent, a vulcanization accelerator, a processing oil, a filler, a coupling agent, an antioxidant, softening agent, and an adhesive.