Vibration damper composition

• US 20030158336A1
• Filed: 02/13/2003
• Published: 08/21/2003
• Est. Priority Date: 04/05/2000
• Status: Active Grant

• Current Assignee: Kaneka Corporation
• Original Assignee: Kaneka Corporation
• Inventors: Kimura, Katsuhiko, Aoyama, Taizo, Yaguchi, Shigeru
• Granted Patent: US 7,241,837 B2
• Time in Patent Office: Days
• US Class Current: 525/95
• CPC Class Codes: C08L 23/04 Homopolymers or copolymers of ethene
• CPC Class Codes: C08L 2666/24 Graft or block copolymers according to groups C08L51/00, C08L53/00 or C08L55/02; Derivatives thereof
• CPC Class Codes: C08L 53/00 Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 53/02 of vinyl-aromatic monomers and conjugated dienes
• CPC Class Codes: Y10T 428/31692 Next to addition polymer from unsaturated monomers

Abstract

The present invention has for its object to provide a damping material which, despite a high damping capacity at and around room temperature, has a small temperature dependence of rigidity at and around room temperature and a damping material having hot-melt processability and a good balance between damping capacity and temperature dependence of rigidity at and around room temperature.

This invention provides a damper material composition

wherein the ratio of the storage modulus (G′) value at 0° C. to the corresponding value at 40° C. as found by the measurement of dynamic viscoelasticity in the shear mode, namely (G′_{0° C.}/G′_{40° C.}), is not greater than 15

and the loss tangent (tan δ) value as found by said measurement is not smaller than 0.4 at 0° C. to 40° C.

Claims

1. A damper material composition

wherein the ratio of the storage modulus (G′

) value at 0°

C. to the corresponding value at 40°

C. as found by the measurement of dynamic viscoelasticity in the shear mode, namely (G′

<sub>0°

C.</sub>/G′

<sub>40°

C.</sub>), is not greater than 15

and the loss tangent (tan δ

) value as found by said measurement is not smaller than 0.4 at 0°

C. to 40°

C.

2. The damper material composition according to claim 1

which comprises a block copolymer (A) comprising a polymer block (a) and a polymer block (b) and terminating in said polymer block (b)

said polymer block (a) being comprised of an aromatic vinyl compound as a constituent monomer

and said polymer block (b) being comprised of isobutylene as a constituent monomer.

3. The damper material composition according to claim 2

wherein the block copolymer (A) is a diblock copolymer having a polymer block (a)—

polymer block (b) structure.

4. The damper material composition according to claim 3

wherein the polymer block (a) has a number average molecular weight of not more than 10,000.

5. The damper material composition according to any of claims 2 to 4

containing at least one kind of a tackifying resin and a plasticizer.

6. The damper material composition according to any of claims 2 to 5

containing at least one kind of thermoplastic resin (C).

7. The damper material composition according to claim 6

wherein the thermoplastic resin (C) is at least one selected from the group consisting of ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, high-density polyethylene, low-density polyethylene, linear low-density polyethylene and isobutylene-isoprene copolymer (butyl rubber).

8. The damper material composition according to any of claims 2 to 7

containing at least one kind of thermoplastic elastomer (D).

9. The damper material composition according to claim 8

wherein the thermoplastic elastomer (D) is at least one selected from the group consisting of a triblock copolymer having the structure of (a polymer block comprised of an aromatic vinyl compound as a constituent monomer)—

(a polymer block comprising a conjugated diene as a constituent monomer and optionally hydrogenated)—

(a polymer block comprised of an aromatic vinyl compound as a constituent monomer) and a triblock copolymer having the structure of (a polymer block comprised of an aromatic vinyl compound as a constituent monomer)—

(a polymer block comprised of isobutylene as a constituent monomer)—

(a polymer block comprised of an aromatic vinyl compound as a constituent monomer).

16. The vibration damper having the structure of a combination of the damper material composition according to any of claims 1 to 15 with steel sheet or steel pipe.

17. A damping double-sided self-adhesive tape comprising the damper material composition according to any of claims 1 to 15 as molded in the form of a tape.

10. A damper material composition comprising a diblock copolymer (A′

) comprising a polymer block (a′

) and a polymer block (b),

said polymer block (a′

) being comprised of an aromatic vinyl compound as a constituent monomer and having a number average molecular weight of not more than 10,000

and said polymer block (b) being comprised of isobutylene as a constituent monomer.

11. The damper material composition according to claim 10

containing at least one kind of thermoplastic elastomer (D).

12. The damper material composition according to claim 11

wherein the thermoplastic elastomer (D) is a triblock copolymer having the structure of (a polymer block comprised of an aromatic vinyl compound as a constituent monomer)—

(a polymer block comprised of a conjugated diene as a constituent monomer and optionally hydrogenated)—

(a polymer block comprised of an aromatic vinyl compound as a constituent monomer).

13. The damper material composition according to any of claims 10 to 12

containing at least one selected from the group consisting of ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, high-density polyethylene, low-density polyethylene, linear low-density polyethylene and isobutylene-isoprene copolymer (butyl rubber).

14. The damper material composition according to any of claims 10 to 13

containing at least one kind of a tackifying resin and a plasticizer.

15. The damper material composition according to any of claims 10 to 14

wherein the ratio of the storage modulus (G′

) value at 10°

C. to the corresponding value at 30°

C. as found by the measurement of dynamic viscoelasticity in the shear mode, namely (G′

<sub>10°

C.</sub>/G′

<sub>30°

C.</sub>), is not greater than 5

and the loss tangent (tan δ

) value as found by said measurement is not smaller than 0.4 at 10°

C. to 30°

C.