JP7461266B2 - Vibration-damping material, manufacturing method for vibration-damping material, laminate, and method for improving vibration-damping properties - Google Patents

Description

The present invention relates to a vibration-damping material, a method for manufacturing a vibration-damping material, a laminate, and a method for improving vibration-damping properties.

A known method of increasing the vibration damping properties of a steel plate is to attach an elastomer material with high vibration damping properties.
However, when attaching a damping layer made of damping elastomer to a steel plate to create a so-called "unrestrained" damping steel plate, in order to achieve high damping properties, the thickness of the damping layer must be at least It needs to be more than twice the size of steel plate. For this reason, non-constraint type vibration damping steel plates have the problem that, when attempting to ensure sufficient vibration damping properties, problems such as an increase in thickness, an increase in weight, and an increase in material cost are likely to occur. Furthermore, since the vibration damping layer is exposed, it is difficult to increase heat resistance. For these reasons, the types of products and technical fields to which non-constrained vibration damping steel plates can be applied are limited.
On the other hand, as a method to improve the damping performance of a steel plate even if the thickness of the damping layer is thin, a restraining layer is pasted on the damping layer side of a non-constraining damping steel plate. It is known that the vibration-damping steel plate is made from a type of vibration-damping steel plate.

For example, Patent Document 1 describes a vibration damping film for a constrained vibration damping steel plate that includes a resin layer made of a block copolymer of a vinyl aromatic compound and a conjugated diene compound or a hydrogenated product thereof. Patent Document 1 describes that steel plates are attached to both sides of this vibration-damping film.

A restrained type vibration damping steel plate is preferable from the viewpoint of suppressing an increase in the weight of the vibration damping layer because it can exhibit vibration damping properties even if the damping layer has a thickness of about 1/10 of the thickness of the steel plate or the restraining layer. However, if a steel plate is used as the restraining layer, the resulting laminate will have a configuration of "steel plate/damping layer/steel plate", which tends to increase the weight of the entire laminate. This causes problems in that it becomes difficult to manufacture the laminate and the weight of the product to which the constrained vibration damping steel plate is applied tends to increase.

Patent Document 2 describes an adhesive vibration-damping material that includes a constraining layer, a first viscoelastic layer laminated on the constraining layer and having a glass transition point of 0°C or higher, and a second viscoelastic layer laminated on the first viscoelastic layer and having a glass transition point below 0°C. Patent Document 2 describes that the second viscoelastic layer of this adhesive vibration-damping material is used by being attached to stainless steel or the like, and that examples of the constraining layer include glass cloth, resin-impregnated glass cloth, metal foil, synthetic resin nonwoven fabric, and carbon fiber.

Japanese Patent Application Publication No. 2000-238193 JP 2013-18242 A

The adhesive type vibration damping material described in Patent Document 2 uses a fibrous material or metal foil as a constraint layer, so it is lighter in weight compared to the constraint type vibration damping steel plate described in Patent Document 1. It is advantageous in this respect. However, if the constraining layer is made of a material such as that described in Patent Document 2, it is difficult to obtain sufficient rigidity, so there is a possibility that necessary vibration damping performance cannot be ensured. Furthermore, if a special material such as glass cloth is used, there is a problem in that it becomes difficult to manufacture the damping material by coextrusion, heat fusion, or the like.
As described above, there is room for improvement in the damping material for obtaining restrained type vibration damping laminates, and it is possible to easily obtain restrained type laminates that have excellent vibration damping properties and light weight. New damping materials are needed.

The objective of the present invention is to provide a vibration-damping material that has excellent vibration-damping properties and is lightweight, and that can easily produce a constrained laminate, a method for producing the same, and a laminate using the same.

The present inventors have proposed a heat-resistant polymer containing a block copolymer (A) having a polymer block containing a structural unit derived from an aromatic vinyl compound and a polymer block containing a structural unit derived from a conjugated diene compound. The above problem can be solved by using a plastic resin composition as a vibration damping layer, using a thermoplastic resin composition having predetermined physical properties as a constraining layer, and setting the thickness of each layer to a predetermined relationship. This discovery led to the completion of the present invention.

The present invention relates to the following [1] to [23].
[1] A vibration-damping material comprising a vibration-damping layer (AL) and a constraining layer (BL) laminated on the vibration-damping layer (AL),
the vibration-damping layer (AL) is made of a thermoplastic resin composition (AC) containing a block copolymer (A) having a polymer block (A-1) containing a structural unit derived from an aromatic vinyl compound and a polymer block (A-2) containing a structural unit derived from a conjugated diene compound;
The constraint layer (BL) is made of a thermoplastic resin composition (BC),
A vibration-damping material that satisfies the following conditions (1) to (3):
(1) The glass transition temperature of the thermoplastic resin composition (AC) is -40 to +30°C.
(2) At least one of the glass transition temperature and the melting point of the thermoplastic resin composition (BC) is 100° C. or higher.
(3) The ratio H(BL)/H(AL) of the thickness H(AL) of the vibration-damping layer (AL) to the thickness H(BL) of the constraining layer (BL) is 3 to 200.
[2] The vibration damping material according to the above [1], wherein the glass transition temperature of the block copolymer (A) is −40 to +30° C.
[3] The vibration damping material according to the above [1] or [2], wherein the content of the polymer block (A-1) in the block copolymer (A) is 22 mass% or less.
[4] The vibration damping material according to any one of the above [1] to [3], wherein the weight average molecular weight of the block copolymer (A) is 30,000 to 200,000.
[5] The vibration damping material according to any one of the above [1] to [4], wherein the block copolymer (A) is a hydrogenated product, and the hydrogenation rate of the polymer block (A-2) is 85 mol % or more.
[6] The vibration-damping material according to any one of the above [1] to [5], wherein the polymer block (A-2) in the block copolymer (A) has a structural unit containing one or more alicyclic skeletons (X) represented by the following formula (X) in the main chain:

(In the above formula (X), R ¹ to R ³ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 11 carbon atoms, and a plurality of R ¹ to R ³ may be the same or different.)
[7] The vibration-damping material according to the above [6], wherein the alicyclic skeleton (X) contains an alicyclic skeleton (X') in which at least one of R ¹ to R ³ is a methyl group.
[8] The vibration-damping material according to the above [6] or [7], wherein the polymer block (A-2) contains the alicyclic skeleton (X) or (X') in an amount of 1 mol % or more.
[9] The vibration-damping material according to any one of the above [1] to [8], wherein the thermoplastic composition (AC) has a tensile storage modulus E'(AC) at 20°C of 100 MPa or less, as measured by a dynamic viscoelasticity test using tensile vibration at a strain of 0.2% and a frequency of 10 Hz in accordance with JIS K7244-4 (1999).
[10] The vibration-damping material according to any one of the above [1] to [9], wherein the loss tangent tanδ at 20 ° C. is 0.3 or more, as measured by performing a dynamic viscoelasticity test using tensile vibration at a strain of 0.2% and a frequency of 10 Hz in accordance with JIS K7244-4 (1999).
[11] The vibration-damping material according to any one of the above [1] to [10], wherein the thickness H(AL) of the vibration-damping layer (AL) is 0.3 mm or less.
[12] The vibration-damping material according to any one of [1] to [11] above, wherein the thermoplastic resin composition (BC) has a tensile storage modulus E'(BC) at 20°C of 1,000 MPa or more, as measured by a dynamic viscoelasticity test using tensile vibration at a strain of 0.2% and a frequency of 10 Hz in accordance with JIS K7244-4 (1999).
[13] The vibration-damping material according to any one of the above [1] to [12], wherein the loss modulus E″(BC) of the thermoplastic resin composition (BC) at 20° C., as measured by a dynamic viscoelasticity test using tensile vibration at a strain of 0.2% and a frequency of 10 Hz in accordance with JIS K7244-4 (1999), is 10 MPa or more.
[14] The vibration damping material according to any one of the above [1] to [13], wherein the thermoplastic resin composition (BC) contains at least one of an olefin resin and a polyamide resin.
[15] The vibration-damping material according to any one of the above [1] to [14], wherein the thickness H(BL) of the constraining layer (BL) is 0.4 mm or more.
[16] The vibration-damping material according to any one of the above [1] to [15], wherein the tensile storage modulus E'(AC) of the thermoplastic composition (AC) and the tensile storage modulus E'(BC) of the thermoplastic composition (BC) at 20°C, as measured in a dynamic viscoelasticity test using tensile vibration at a strain of 0.2% and a frequency of 10 Hz in accordance with JIS K7244-4 (1999), satisfy the relationship E'(BC)/E'(AC)≧50.
[17] The ratio H(BL)/H(AL) of the thickness H(BL) of the constraining layer (BL) to the thickness H(AL) of the vibration-damping layer (AL) is 8 to 100. Any one of the vibration-damping materials described in [1] to [16] above.
[18] The vibration-damping material according to any one of the above [1] to [17], wherein the vibration-damping layer (AL) is a layer coextruded with the constraining layer (BL).
[19] The vibration-damping material according to any one of the above [1] to [17], which is obtained by heat-sealing the vibration-damping layer (AL) and the constraining layer (BL).
[20] A method for producing a vibration-damping material according to any one of the above [1] to [19], comprising co-extruding a vibration-damping layer (AL) and a constraining layer (BL) to produce the vibration-damping material.
[21] A method for producing a vibration-damping material according to any one of the above [1] to [19], comprising molding a vibration-damping layer (AL) and a constraining layer (BL) separately, laminating the layers, and heat fusing the layers to produce the vibration-damping material.
[22] A laminate comprising the vibration-damping material according to any one of [1] to [19] above and a metal plate laminated on the vibration-damping material.
[23] A method for improving vibration-damping properties, comprising attaching the vibration-damping material according to any one of [1] to [19] above to a metal plate to improve the vibration-damping properties of the metal plate.

The present invention provides a vibration-damping material that has excellent vibration-damping properties and is lightweight, and that can easily produce a constrained laminate, a method for producing the same, and a laminate using the same.

FIG. 2 is a schematic cross-sectional view showing an example of a damping material and a laminate. It is a typical sectional view showing other examples of a damping material and a layered product.

Embodiments of the present invention will be described below.
The present invention also includes embodiments in which the items described in this specification are arbitrarily selected or embodiments in which the items described in this specification are arbitrarily combined.
In this specification, preferred regulations can be arbitrarily selected, and combinations of preferred regulations can be said to be more preferable.
In this specification, the expression "XX to YY" means "XX to YY".
In this specification, the lower and upper limits described in stages for preferred numerical ranges (for example, ranges of content, etc.) can be independently combined. For example, from the description "preferably 10 to 90, more preferably 30 to 60", the "preferable lower limit (10)" and "more preferable upper limit (60)" are combined to become "10 to 60". You can also do that.

[Vibration damping material]
The damping material according to the embodiment of the present invention is a damping material comprising a damping layer (AL) and a constraining layer (BL) laminated on the damping layer (AL),
The damping layer (AL) includes a polymer block (A-1) containing a structural unit derived from an aromatic vinyl compound and a polymer block (A-2) containing a structural unit derived from a conjugated diene compound. consisting of a thermoplastic resin composition (AC) containing a block copolymer (A) having
The constraining layer (BL) is made of a thermoplastic resin composition (BC),
The following conditions (1) to (3) are satisfied.
(1) The glass transition temperature of the thermoplastic resin composition (AC) is -40 to +30°C.
(2) At least one of the glass transition temperature and melting point of the thermoplastic resin composition (BC) is 100°C or higher.
(3) The ratio H(BL)/H(AL) of the thickness H(BL) of the constraining layer (BL) to the thickness H(AL) of the damping layer (AL) is 3 to 200.

By satisfying the condition (1), the thermoplastic resin composition (AC) has appropriate viscoelastic properties (for example, tensile storage modulus and loss tangent), and the vibration-damping layer (AL) exhibits high vibration-damping properties.
In addition, by satisfying the condition (2), the thermoplastic resin composition (BC) generally has good mechanical properties (e.g., tensile storage modulus and loss modulus), and therefore the mechanical properties of the constraint layer (BL) are improved.
Furthermore, by satisfying the condition (3), the constraining layer (BL) becomes sufficiently thicker than the vibration-damping layer (AL) and has sufficient rigidity while being lightweight.
Therefore, by satisfying the above conditions (1) to (3), the vibration-damping material has excellent vibration-damping properties and light weight, and by attaching the vibration-damping material to a metal plate such as a steel plate, a constrained-type laminate having a configuration of "metal plate/vibration-damping layer (AL)/constraining layer (BL)" that has excellent vibration-damping properties and light weight can be easily produced.

Fig. 1 is a schematic cross-sectional view showing an example of a vibration-damping material and a laminate. Fig. 2 is a schematic cross-sectional view showing another example of a vibration-damping material and a laminate. An example of a specific configuration of the vibration-damping material and the laminate will be described based on Figs. 1 and 2. Note that the present invention is not limited to those shown in Figs. 1 and 2.
The vibration-damping material 100 shown in FIG. 1(A) includes a vibration-damping layer (AL) and a constraining layer (BL) laminated on the vibration-damping layer (AL).
By attaching the side of the vibration-damping material 100 opposite the constraining layer (BL) (i.e., the vibration-damping layer (AL)) to a metal plate such as a steel plate, which is the target object, a constrained-type laminate having a structure of "metal plate/vibration-damping layer (AL)/constraining layer (BL)" can be obtained.
Since the constraining layer (BL) is made of the thermoplastic resin composition (BC), a lightweight vibration-damping material can be obtained. In addition, the lightweight vibration-damping material makes it easier to manufacture the laminate than manufacturing a constrained vibration-damping steel plate having a "steel plate/vibration-damping layer/steel plate" structure.

The laminate 200 shown in FIG. 1(B) includes the damping material 100 shown in FIG. 1(A) and the metal plate 10.
As described above, the laminate 200 is obtained by attaching the surface of the damping material 100 opposite to the constraining layer (BL) (that is, the damping layer (AL)) to the metal plate 10.
The laminate 200 has a constrained structure of "metal plate/damping layer (AL)/constrained layer (BL)" and thus has high vibration damping properties. In addition, since the constraining layer (BL) is made of a thermoplastic resin composition (BC), the laminate can be made lighter compared to a damping steel plate having the structure of "steel plate/damping layer/steel plate". can be taken as a thing.

The vibration-damping material according to the embodiment of the present invention may have a structure in which the constraining layer (BL) and the vibration-damping layer (AL) are repeatedly laminated.
The vibration-damping material 101 shown in Figure 2 (A) has a structure in which a first constraining layer (BL1), a first vibration-damping layer (AL1), a second constraining layer (BL2), a second vibration-damping layer (AL2), and a third constraining layer are stacked in this order.
By attaching the first constraining layer (BL1) or the third constraining layer (BL3) of the vibration-damping material 101 to a metal plate such as a steel plate, which is the target object, a constrained-type laminate having a structure of "metal plate/constraining layer (BL1)/vibration-damping layer (AL1)/constraining layer (BL2)/vibration-damping layer (AL2)/constraining layer (BL3)" can be obtained.
One of the first constraining layer (BL1) and the third constraining layer (BL3) located on the outermost side may be omitted. In this case, the first vibration-damping layer (AL1) or the third vibration-damping layer (AL3) located on the outermost side may be attached to the metal plate 10.
The vibration-damping material may have a configuration in which the constraining layer (BL) and the vibration-damping layer (AL) are repeatedly laminated three or more times.
By making the vibration-damping material have a structure in which a constraining layer (BL) and a vibration-damping layer (AL) are repeatedly laminated, the vibration-damping properties and mechanical strength of the vibration-damping material can be increased, and by changing the number of repeated laminations, the vibration-damping properties and mechanical strength of the vibration-damping material can be adjusted.

The laminate 201 shown in FIG. 2(B) includes the damping material 101 shown in FIG. 2(A) and the metal plate 10.
The laminate 201 is obtained by attaching the first constraining layer (BL1) of the damping material 101 to the metal plate 10. As described above, the third constraint layer (BL3) may be attached to the metal plate 10.
Since the laminate 201 has a structure in which a restraining layer (BL) and a vibration damping layer (AL) are repeatedly laminated, it becomes easier to improve vibration damping properties. In addition, since the constraining layer (BL) is made of a thermoplastic resin composition (BC) and the repeating unit consisting of the constraining layer (BL) and damping layer (AL) can be made lightweight, the laminate is Vibration damping performance can be improved while suppressing weight increase.

The vibration-damping material may be provided with a protective layer. Specifically, a protective layer may be provided on at least one of the surfaces of the vibration-damping layer (AL) and the constraining layer (BL) of the vibration-damping material 100 in FIG. 1, and at least one of the surfaces of the constraining layer (BL1) and the constraining layer (BL3) of the vibration-damping material 101 in FIG. 2. By providing the protective layer, the vibration-damping layer (AL) and the constraining layer (BL) of the vibration-damping material before being attached to the metal plate can be protected from the external environment and external objects. Of the above protective layers, the protective layer located on the surface to be attached to the metal plate may be peeled off and removed before being attached to the metal plate. In addition, of the above protective layers, the protective layer located on the surface to be attached to the metal plate may be peeled off and removed at any timing before, during, or after attachment to the metal plate.
The vibration-damping material and each layer constituting the laminate will now be described in detail.

<Vibration Damping Layer (AL)>
The vibration-damping layer (AL) is made of a thermoplastic resin composition (AC) containing a block copolymer (A) having a polymer block (A-1) containing a structural unit derived from an aromatic vinyl compound and a polymer block (A-2) containing a structural unit derived from a conjugated diene compound.
The vibration-damping layer (AL) is a layer that has a function of imparting vibration-damping properties to a constrained laminate obtained by attaching a vibration-damping material to a metal plate. The vibration-damping layer (AL) is made of a material different from the constraining layer (BL) and has a vibration-damping property at least higher than that of the constraining layer (BL).

The thermoplastic resin composition (AC) constituting the vibration-damping layer (AL) may consist of the block copolymer (A) alone, may consist of only the block copolymer (A) and other resin components, or may contain various additives in addition to these resin components. Components other than the resin components that may be contained in the thermoplastic resin composition (AC) will be described later.

The thickness H(AL) of the vibration-damping layer (AL) is preferably 0.3 mm or less, more preferably 0.25 mm or less, and even more preferably 0.15 mm or less, from the viewpoint of the mechanical properties of the laminate, and is preferably 0.01 mm or more, more preferably 0.02 mm or more, and even more preferably 0.03 mm or more, from the viewpoint of ensuring sufficient vibration-damping properties. In other words, the thickness H(AL) of the vibration-damping layer (AL) is preferably 0.01 to 0.3 mm, from the viewpoint of achieving both vibration-damping properties and mechanical properties of the laminate.

The damping layer (AL) can be a layer co-extruded with the constraining layer (BL), as described below.
Furthermore, as will be described later, the damping layer (AL) and the constraint layer (BL) may be thermally fused together.

(Thermoplastic resin composition (AC))
The thermoplastic resin composition (AC) constituting the vibration-damping layer (AL) contains a block copolymer (A) having a polymer block (A-1) containing a structural unit derived from an aromatic vinyl compound and a polymer block (A-2) containing a structural unit derived from a conjugated diene compound.
The thermoplastic resin composition (AC) is a different type of composition from the thermoplastic resin composition (BC), and has a vibration-damping property higher than that of the thermoplastic resin composition (BC). The thermoplastic resin composition (AC) may be composed of the block copolymer (A) alone, or may contain a resin component other than the block copolymer (A). The resin component other than the block copolymer (A) will be described later.
As specified by the above condition (1), the glass transition temperature Tg of the thermoplastic resin composition (AC) is -40 to +30°C.
When the Tg of the thermoplastic resin composition (AC) is within the above range, the thermoplastic resin composition (AC) has appropriate viscoelastic properties (e.g., tensile storage modulus and loss tangent), and therefore the vibration-damping layer (AL) exhibits high vibration-damping properties.
From the viewpoint of easily ensuring appropriate viscoelastic properties, the Tg of the thermoplastic resin composition (AC) is preferably −35 to +25° C., more preferably −30 to +20° C., and even more preferably −20 to +15° C. From the viewpoint of improving vibration damping properties at high temperatures, the Tg is preferably −10 to +30° C., more preferably −5 to +30° C., and even more preferably 0 to +30° C.
The glass transition temperature of the thermoplastic resin composition (AC) can be adjusted to the above range, for example, by controlling the amount of vinyl bonds in the conjugated diene of the polymer block (A-2) in the block copolymer (A) contained in the thermoplastic resin composition (AC) to an appropriate value.
In this specification, the Tg of the thermoplastic resin composition (AC) is defined as the temperature at which a baseline shift occurs in a DSC curve prepared using a differential scanning calorimeter (DSC), and is specifically measured by the method described in the Examples. Even when the thermoplastic resin composition (AC) contains an infusible additive among the additives described below, the temperature measured by the above method is defined as the Tg of the thermoplastic resin composition (AC).

The tensile storage modulus E'(AC) of the thermoplastic resin composition (AC) at 20°C, measured by performing a dynamic viscoelasticity test using tensile vibration at a strain of 0.2% and a frequency of 10 Hz in accordance with JIS K7244-4 (1999), is preferably 800 MPa or less, more preferably 300 MPa or less, even more preferably 100 MPa or less, and particularly preferably 50 MPa or less from the viewpoint of ensuring vibration damping properties, and is preferably 1 MPa or more, more preferably 3 MPa or more, and even more preferably 5 MPa or more from the viewpoint of improving the mechanical properties of the laminate. In other words, the tensile storage modulus E'(AC) of the thermoplastic resin composition (AC) is preferably 1 to 800 MPa.
The tensile storage modulus E' of the thermoplastic resin composition (AC) can be adjusted to the above range, for example, by controlling the content of the polymer block (A-1) in the block copolymer (A) contained in the thermoplastic resin composition (AC) to an appropriate value.

The loss tangent tanδ at 20°C of the thermoplastic composition (AC), measured in accordance with JIS K7244-4 (1999) by performing a dynamic viscoelasticity test using tensile vibration at a strain of 0.2% and a frequency of 10 Hz, is preferably 0.1 or more, more preferably 0.2 or more, even more preferably 0.3 or more, and particularly preferably 0.4 or more, from the viewpoint of ensuring vibration damping properties, and is preferably 3.0 or less, more preferably 2.5 or less, and even more preferably 2.0 or less, from the viewpoint of achieving both mechanical properties and vibration damping properties. In other words, the above tanδ of the thermoplastic resin composition (AC) is preferably 0.1 to 3.0.

The above tensile storage modulus E' and tan δ of the thermoplastic resin composition (AC) can be set within the above ranges by, for example, setting the Tg of the thermoplastic resin composition (AC) within the above range. .

Next, the constituent elements of the block copolymer (A) contained in the thermoplastic resin composition (AC), the physical properties of the block copolymer (A), the method for producing the block copolymer (A), etc. will be described in detail. .

(Block Copolymer (A))
The block copolymer (A) is a block copolymer having a polymer block (A-1) and a polymer block (A-2), and is preferably a hydrogenated block copolymer. In this specification, the hydrogenated block copolymer may also be referred to as a "hydrogenated block copolymer."
The block copolymer (A) contained in the thermoplastic resin composition (AC) has a polymer block (A-1) containing a structural unit derived from an aromatic vinyl compound, and a polymer block (A-2) containing a structural unit derived from a conjugated diene compound.

The Tg of the block copolymer (A) or its hydrogenated product is preferably -40 to +30°C, more preferably -35 to +25°C, still more preferably - The temperature is 30 to +20°C, more preferably -20 to +15°C. Further, from the viewpoint of improving damping properties at high temperatures, the temperature is preferably -10 to +30°C, more preferably -5 to +30°C, and still more preferably 0 to +30°C.
The Tg of the block copolymer (A) or its hydrogenated product can be determined, for example, by controlling the amount of vinyl bonds in the conjugated diene of the polymer block (A-2) in the block copolymer (A) to an appropriate value. , can be within the above range.

(Polymer block (A-1))
The polymer block (A-1) contains a structural unit derived from an aromatic vinyl compound (hereinafter sometimes abbreviated as "aromatic vinyl compound unit"), and preferably contains 70 mol from the viewpoint of mechanical properties. %, more preferably 80 mol% or more, still more preferably 85 mol% or more, even more preferably 90 mol% or more, particularly preferably 95 mol% or more, and may be substantially 100 mol%.

Examples of the aromatic vinyl compounds include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, β-methylstyrene, 2,6-dimethylstyrene, 2,4-dimethylstyrene, α-Methyl-o-methylstyrene, α-methyl-m-methylstyrene, α-methyl-p-methylstyrene, β-methyl-o-methylstyrene, β-methyl-m-methylstyrene, β-methyl-p -Methylstyrene, 2,4,6-trimethylstyrene, α-methyl-2,6-dimethylstyrene, α-methyl-2,4-dimethylstyrene, β-methyl-2,6-dimethylstyrene, β-methyl- 2,4-dimethylstyrene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, 2,6-dichlorostyrene, 2,4-dichlorostyrene, α-chloro-o-chlorostyrene, α-chloro-m -Chlorostyrene, α-chloro-p-chlorostyrene, β-chloro-o-chlorostyrene, β-chloro-m-chlorostyrene, β-chloro-p-chlorostyrene, 2,4,6-trichlorostyrene, α -Chloro-2,6-dichlorostyrene, α-chloro-2,4-dichlorostyrene, β-chloro-2,6-dichlorostyrene, β-chloro-2,4-dichlorostyrene, ot-butylstyrene, m-t-butylstyrene, pt-butylstyrene, o-methoxystyrene, m-methoxystyrene, p-methoxystyrene, o-chloromethylstyrene, m-chloromethylstyrene, p-chloromethylstyrene, o-bromo Examples include methylstyrene, m-bromomethylstyrene, p-bromomethylstyrene, styrene derivatives substituted with silyl groups, indene, and vinylnaphthalene. These aromatic vinyl compounds may be used alone or in combination of two or more. Among these, from the viewpoint of production cost and physical property balance, styrene, α-methylstyrene, p-methylstyrene, and mixtures thereof are preferred, and styrene is more preferred.

However, the polymer block (A-1) may contain structural units derived from other unsaturated monomers other than the aromatic vinyl compound (hereinafter referred to as "other unsaturated monomers"), as long as this does not interfere with the purpose and effects of the present invention. (sometimes abbreviated as "mer unit") in a proportion of less than 30 mol%. Examples of the other unsaturated monomers include butadiene, isoprene, 2,3-dimethylbutadiene, 1,3-pentadiene, 1,3-hexadiene, isobutylene, methyl methacrylate, methyl vinyl ether, N-vinylcarbazole, β At least one selected from the group consisting of -pinene, 8,9-p-menthene, dipentene, methylene norbornene, 2-methylenetetrahydrofuran, and the like. When the polymer block (A-1) contains the other unsaturated monomer units, the bonding form is not particularly limited and may be either random or tapered.
The content of the structural unit derived from the other unsaturated monomer in the polymer block (A-1) is preferably 10 mol% or less, more preferably 5 mol% or less, and even more preferably 0 mol%. .

The block copolymer (A) only needs to have at least one of the above polymer blocks (A-1). When the block copolymer (A) has two or more polymer blocks (A-1), these polymer blocks (A-1) may be the same or different. In addition, in this specification, "the polymer blocks are different" refers to the monomer units constituting the polymer blocks, the weight average molecular weight, the stereoregularity, and when the polymer blocks have multiple monomer units, the ratio and co-existence of each monomer unit. It means that at least one of the polymerization forms (random, gradient, block) is different.
The block copolymer (A) preferably has two polymer blocks (A-1).

The weight average molecular weight (Mw) of the polymer block (A-1) is not particularly limited, but the weight average molecular weight of at least one of the polymer blocks (A-1) contained in the block copolymer (A) is preferably 3,000 to 60,000, more preferably 4,000 to 50,000. When the block copolymer (A) has at least one polymer block (A-1) having a weight average molecular weight within the above range, the mechanical strength is further improved and the film formability is also excellent.

In addition, all "weight average molecular weights" described in the present specification and claims are standard polystyrene-equivalent weight average molecular weights determined by gel permeation chromatography (GPC), and the detailed measurement method can be according to the method described in the Examples. The weight average molecular weight of each polymer block of the block copolymer (A) can be determined by measuring a sampled liquid each time the polymerization of each polymer block is completed in the production process. In addition, for example, when two types of polymer blocks (A-1) are represented by "A1" and "A2", and one type of polymer block (A-2) is represented by "B", in the case of a triblock copolymer having a structure of A1-B-A2, the weight average molecular weights of the polymer block "A1" and the polymer block "B" are determined by the above method, and the weight average molecular weight of the polymer block "A2" can be determined by subtracting them from the weight average molecular weight of the block copolymer. As another method, in the case of a triblock copolymer having the above-mentioned A1-B-A2 structure, the total weight average molecular weight of the polymer blocks "A1" and "A2" can be calculated from the weight average molecular weight of the block copolymer and the total content of the polymer blocks "A1" and "A2" confirmed by ^1H -NMR measurement, and the weight average molecular weight of the deactivated initial polymer block "A1" is calculated by GPC measurement, and the weight average molecular weight of the polymer block "A2" can be obtained by subtracting this.

The content of the polymer block (A-1) in the block copolymer (A) (if it has a plurality of polymer blocks (A-1), their total content) is preferably from the viewpoint of damping properties. is 22% by mass or less, more preferably 18% by mass or less, even more preferably 15% by mass or less, and from the viewpoint of mechanical properties, preferably 3% by mass or more, more preferably 5% by mass or more, even more preferably It is 7% by mass or more. In other words, the content of the polymer block (A-1) in the block copolymer (A) is preferably 3 to 22% by mass.
The content of the polymer block (A-1) in the block copolymer (A) is a value determined by ¹ H-NMR measurement, and more specifically, a value determined according to the method described in the Examples. be.

(Polymer block (A-2))
The polymer block (A-2) contains a structural unit derived from a conjugated diene compound (hereinafter sometimes abbreviated as "conjugated diene compound unit"). From the viewpoint of vibration damping properties and thermal stability, the content of conjugated diene compound units in the polymer block (A-2) is preferably 30 mol% or more, more preferably 50 mol% or more, and even more preferably 65 mol%. The content is more preferably 80 mol% or more, particularly preferably 90 mol% or more, and most preferably substantially 100 mol%.
Note that the above-mentioned "conjugated diene compound unit" may be a structural unit derived from one type of conjugated diene compound, or may be a structural unit derived from two or more types of conjugated diene compounds.

The conjugated diene compound preferably contains isoprene or isoprene and butadiene from the viewpoint of achieving both excellent vibration damping properties and thermal stability. Further, as the conjugated diene compound, a conjugated diene compound other than isoprene and butadiene may be contained as described later. On the other hand, from the viewpoint of facilitating the expression of excellent vibration damping properties and thermal stability, the content of isoprene in the conjugated diene compound is preferably 20% by mass or more, more preferably 40% by mass or more, and even more preferably 45% by mass. % or more, even more preferably 55% by weight or more, even more preferably 75% by weight or more, particularly preferably 100% by weight, that is, it is particularly preferable to use isoprene as the conjugated diene compound.

Further, when the conjugated diene compound is a mixture of butadiene and isoprene, the mixing ratio [isoprene/butadiene] (mass ratio) is not particularly limited as long as it does not impair the effects of the present invention, but is preferably 5/95. ~95/5, more preferably 10/90 ~ 90/10, still more preferably 40/60 ~ 70/30, particularly preferably 45/55 ~ 65/35. In addition, when the mixing ratio [isoprene/butadiene] is expressed as a molar ratio, it is preferably 5/95 to 95/5, more preferably 10/90 to 90/10, still more preferably 40/60 to 70/30, especially Preferably it is 45/55 to 55/45.

In addition to the above-mentioned isoprene and butadiene, examples of the conjugated diene compound include hexadiene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, and myrcene. The conjugated diene compound may be used alone or in combination of two or more kinds.

In addition, the polymer block (A-2) may contain structural units derived from polymerizable monomers other than the conjugated diene compound, so long as the purpose and effects of the present invention are not hindered. In this case, the content of structural units derived from polymerizable monomers other than the conjugated diene compound in the polymer block (A-2) is preferably less than 70 mol%, more preferably less than 50 mol%, even more preferably less than 35 mol%, and particularly preferably less than 20 mol%. There is no particular limit to the lower limit of the content of structural units derived from polymerizable monomers other than the conjugated diene compound, but it may be 0 mol%, 5 mol%, or 10 mol%.

Examples of the other polymerizable monomers include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, pt-butylstyrene, 2,4-dimethylstyrene, vinyl Aromatic vinyl compounds such as naphthalene and vinylanthracene, as well as methyl methacrylate, methyl vinyl ether, N-vinylcarbazole, β-pinene, 8,9-p-menthene, dipentene, methylenenorbornene, 2-methylenetetrahydrofuran, 1,3- Preferred examples include at least one compound selected from the group consisting of cyclopentadiene, 1,3-cyclohexadiene, 1,3-cycloheptadiene, 1,3-cyclooctadiene, and the like. Among these, styrene, α-methylstyrene, and p-methylstyrene are preferred, and styrene is more preferred.

The block copolymer (A) may have at least one polymer block (A-2). When the block copolymer (A) has two or more polymer blocks (A-2), the polymer blocks (A-2) may be the same or different. When the polymer block (A-2) has two or more types of structural units, the bonding form thereof may be random, tapered, completely alternating, partially block-like, block, or a combination of two or more of these.

There is no particular restriction on the bonding form of the conjugated diene compound as long as it does not impair the purpose and effects of the present invention. For example, when the structural unit constituting the polymer block (A-2) is either an isoprene unit or a mixture unit of isoprene and butadiene, the bonding form of each of isoprene and butadiene is 1 in the case of butadiene, Vinyl bonds such as 2-bond, 1,4-bond, and in the case of isoprene, 1,2-bond, 3,4-bond, and 1,4-bond can be used. Only one type of these bonding forms may be present, or two or more types may be present.

The polymer block (A-2) is a structural unit derived from a conjugated diene compound and contains one or more alicyclic skeletons (X) represented by the following formula (X) in the main chain. may have.

(In the above formula (X), R ¹ to R ³ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 11 carbon atoms, and a plurality of R ¹ to R ³ may be the same or different.)
The hydrocarbon group preferably has 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms, and still more preferably 1 (ie, methyl group).
Moreover, the above-mentioned hydrocarbon group may be a straight chain or branched chain, and may be a saturated or unsaturated hydrocarbon group. From the viewpoint of physical properties and alicyclic skeleton (X) formation, it is particularly preferable that R ¹ to R ³ are each independently a hydrogen atom or a methyl group.

From the viewpoint of improving vibration damping properties, the alicyclic skeleton (X) may include an alicyclic skeleton (X') in which at least one of R ¹ to R ³ is a methyl group.

From the viewpoint of improving vibration damping properties, the content of the alicyclic skeleton (X) or (X') in the polymer block (A-2) is preferably 1 mol% or more, more preferably 1.1 mol% or more, even more preferably 1.4 mol% or more, even more preferably 1.8 mol% or more, even more preferably 4 mol% or more, even more preferably 10 mol% or more, and particularly preferably 13 mol% or more. In addition, the upper limit of the content of the alicyclic skeleton (X) or (X') in the polymer block (A-2) is not particularly limited as long as it is within a range that does not impair the effects of the present invention, but from the viewpoint of productivity, it is preferably 40 mol% or less, may be 30 mol% or less, may be 20 mol% or less, or may be 18 mol% or less. In other words, the content of the alicyclic skeleton (X) or (X') in the polymer block (A-2) is preferably 1 to 40 mol%.

As described later, the alicyclic skeleton (X) is generated by anionic polymerization of a conjugated diene compound, and depending on the conjugated diene compound used, at least one kind of alicyclic skeleton (X) is formed of the alicyclic skeleton-containing unit. Introduced into the main chain. Since the alicyclic skeleton (X) is incorporated into the main chain of the structural unit contained in the polymer block (A-2), the molecular movement becomes smaller, the glass transition temperature increases, and the tan δ at around room temperature increases. The peak top strength of is increased, making it easier to develop excellent vibration damping properties.

As a specific example, the alicyclic skeleton (X) mainly produced when butadiene, isoprene, or a combination of butadiene and isoprene is used as the conjugated diene compound will be described.
When butadiene is used alone as the conjugated diene compound, an alicyclic skeleton (X) having the following combination of substituents (i) is produced. That is, in this case, the alicyclic skeleton (X) is only an alicyclic skeleton in which R ¹ to R ³ are hydrogen atoms at the same time. Therefore, the polymer block (A-2) is a block copolymer having a structural unit containing one type of alicyclic skeleton (X) in the main chain in which R ¹ to R ³ are hydrogen atoms, or a hydrogen atom thereof. Additives can be obtained.
Furthermore, when isoprene is used alone as the conjugated diene compound, two types of alicyclic skeletons (X) having the following combinations of substituents (v) and (vi) are mainly produced.
Furthermore, when butadiene and isoprene are used together as a conjugated diene compound, six types of alicyclic skeletons (X) having the following combinations of substituents (i) to (vi) are mainly produced.
(i) : R ¹ = hydrogen atom, R ² = hydrogen atom, R ³ = hydrogen atom (ii) : R ¹ = hydrogen atom, R ² = methyl group, R ³ = hydrogen atom (iii) : R ¹ = hydrogen atom, R ² = hydrogen atom, R ³ = methyl group (iv): R ¹ = methyl group, R ² = hydrogen atom, R ³ = hydrogen atom (v): R ¹ = methyl group, R ² = methyl group, R ³ = hydrogen atom (vi): R ¹ = methyl group, R ² = hydrogen atom, R ³ = methyl group

In particular, it is more preferable that R ¹ to R ³ each independently represent a hydrogen atom or a methyl group, and that R ¹ to R ³ are also an alicyclic skeleton that is not a hydrogen atom. That is, the polymer block (A-2) may have a structural unit containing one or more types of alicyclic skeletons having combinations of substituents (ii) to (vi) above in the main chain. More preferred.

When the block copolymer (A) is hydrogenated, the vinyl group in the above formula (X) can be hydrogenated to give a hydrogenated product, and therefore the meaning of the alicyclic skeleton (X) in the hydrogenated product also includes a skeleton in which the vinyl group in the above formula (X) has been hydrogenated.
The content of the alicyclic skeleton (X) in the block copolymer (A) or the hydrogenated additive thereof is a value determined from an integral value derived from the alicyclic skeleton (X) in the polymer block (A-2) by ^13C -NMR measurement of the block copolymer (A).

(Amount of vinyl bonds in polymer block (A-2))
When the structural unit constituting the polymer block (A-2) is either an isoprene unit or a mixture unit of isoprene and butadiene, the bonding form of each isoprene and butadiene is 1,2- in the case of butadiene. In the case of isoprene, it can be a 1,2-bond, a 3,4-bond, or a 1,4-bond.
In the block copolymer (A), the sum of the content of 3,4-bond units and 1,2-bond units (that is, the amount of vinyl bonds) in the polymer block (A-2) has vibration damping properties. From this point of view, the content is preferably 35 mol% or more, more preferably 40 mol% or more, still more preferably 50 mol% or more, even more preferably 60 mol% or more. Although not particularly limited, the upper limit of the amount of vinyl bonds in the polymer block (A-2) may be 95 mol%, 92 mol%, or 90 mol%. It may be mol%. In other words, the amount of vinyl bonds in the polymer block (A-2) is preferably 35 to 95 mol%. Here, the vinyl bond amount is a value calculated by ¹ H-NMR measurement according to the method described in Examples.

From the viewpoint of vibration damping properties, etc., the total weight average molecular weight of the polymer blocks (A-2) in the block copolymer (A) is preferably 15,000 to 800,000, more preferably 20,000 to 400,000, even more preferably 20,000 to 300,000, particularly preferably 30,000 to 300,000, and most preferably 40,000 to 300,000 before hydrogenation.

The polymer block (A-2) may contain a structural unit derived from a polymerizable monomer other than the conjugated diene compound, as long as it does not impede the object and effect of the present invention. In this case, the content of the structural unit derived from the polymerizable monomer other than the conjugated diene compound in the polymer block (A-2) is preferably 70 mol% or less, more preferably 50 mol% or less, even more preferably 35 mol% or less, and particularly preferably 20 mol% or less. There is no particular restriction on the lower limit of the content of the structural unit derived from the polymerizable monomer other than the conjugated diene compound, but it may be 0 mol%, 5 mol%, or 10 mol%.
Preferred examples of the other polymerizable monomer include aromatic vinyl compounds such as styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-t-butylstyrene, 2,4-dimethylstyrene, vinylnaphthalene, and vinylanthracene, as well as at least one compound selected from the group consisting of methyl methacrylate, methyl vinyl ether, N-vinylcarbazole, β-pinene, 8,9-p-menthene, dipentene, methylenenorbornene, 2-methylenetetrahydrofuran, 1,3-cyclopentadiene, 1,3-cyclohexadiene, 1,3-cycloheptadiene, 1,3-cyclooctadiene, etc. Among these, styrene, α-methylstyrene, and p-methylstyrene are preferred, and styrene is more preferred.
When the polymer block (A-2) contains a structural unit derived from a polymerizable monomer other than a conjugated diene compound, the bonding form is not particularly limited and may be either random or tapered, but is preferably random.

The block copolymer (A) only needs to have at least one of the above polymer blocks (A-2). When the block copolymer (A) has two or more polymer blocks (A-2), these polymer blocks (A-2) may be the same or different.
It is preferable that the block copolymer (A) has only one of the above polymer blocks (A-2).

Note that in the block copolymer (A) contained in the thermoplastic resin composition (AC), it is desirable that the polymer block (A-2) does not contain a structural unit derived from an aromatic vinyl compound. If the polymer block (A-2) contains a structural unit derived from an aromatic vinyl compound, vibration damping properties may be reduced.

(Bonding mode of polymer block (A-1) and polymer block (A-2))
The bonding form of the block copolymer (A) is not limited as long as the polymer block (A-1) and the polymer block (A-2) are bonded together; linear, branched, The coupling mode may be either radial or a combination of two or more of these. Among them, it is preferable that the bonding form between the polymer block (A-1) and the polymer block (A-2) is linear, and as an example, the polymer block (A-1) is "A", Also, when the polymer block (A-2) is represented by "B", a diblock copolymer represented by AB, a triblock copolymer represented by ABA or BAB , a tetrablock copolymer represented by ABAB, a pentablock copolymer represented by ABABA or BABAB, (AB) Examples include nX type copolymers (X represents a coupling agent residue, and n represents an integer of 3 or more). Among these, linear triblock copolymers or diblock copolymers are preferred, and ABA type triblock copolymers are preferably used from the viewpoint of flexibility, ease of production, and the like.
Here, in this specification, when polymer blocks of the same type are linearly bonded via a bifunctional coupling agent, the entire bonded polymer block is treated as one polymer block. It will be done. Accordingly, including the above example, the polymer block that should be technically written as Y-X-Y (X represents a coupling residue) needs to be particularly distinguished from the single polymer block Y. Except in certain cases, Y is displayed as a whole. In this specification, this type of polymer block containing a coupling agent residue is treated as described above, so for example, a polymer block containing a coupling agent residue and strictly speaking A-B-X-B-A ( A block copolymer to be written as (X represents a coupling agent residue) is written as ABA and is treated as an example of a triblock copolymer.

The block copolymer (A) is preferably a hydrogenated product. The hydrogenation rate of the polymer block (A-2) is preferably 85 mol % or more. In other words, it is preferred that 85 mol % or more of the carbon-carbon double bonds in the polymer block (A-2) are hydrogenated.
When the hydrogenation rate of the polymer block (A-2) is high, the vibration damping property, heat resistance and weather resistance are excellent over a wide range of temperatures. From the same viewpoint, the hydrogenation rate of the polymer block (A-2) is more preferably 87 mol% or more, more preferably 88 mol% or more, even more preferably 89 mol% or more, and particularly preferably 90 mol% or more. This value may be referred to as the hydrogenation rate (hydrogenation ratio). There is no particular restriction on the upper limit of the hydrogenation rate, but the upper limit may be 99 mol% or 98 mol%. In other words, the hydrogenation rate of the block copolymer (A-2) is preferably 85 to 99 mol%.
The hydrogenation rate is a value obtained by measuring the content of carbon-carbon double bonds in the structural units derived from the conjugated diene compound in the polymer block (A-2) by ¹ H-NMR measurement after hydrogenation, and more specifically, a value measured according to the method described in the examples.

(Weight average molecular weight (Mw) of block copolymer (A))
The weight average molecular weight (Mw) of the block copolymer (A) or a hydrogenated product thereof, as determined by gel permeation chromatography in terms of standard polystyrene, is preferably 20,000 to 500,000, more preferably 25,000 to 400,000, even more preferably 28,000 to 350,000, particularly preferably 29,000 to 300,000, and most preferably 30,000 to 200,000, from the viewpoints of heat resistance and moldability.
The weight average molecular weight of the block copolymer (A) or its hydrogenated product can be adjusted to the above range, for example, by adjusting the amount of monomer relative to the polymerization initiator.

The block copolymer (A) may contain functional groups such as carboxyl groups, hydroxyl groups, acid anhydride groups, amino groups, and epoxy groups in the molecular chain and/or at the molecular ends, unless the purpose and effects of the present invention are impaired. , or may have one or more types, or may have no functional group.

The peak top temperature of tan δ of the block copolymer (A) or its hydrogenated product measured according to JIS K 7244-4 (1999) is -50°C or higher, which is sufficient under the actual usage environment. If the temperature is +50°C or lower, it is easy to ensure the flexibility required as a vibration damping material.
In addition, the higher the tan δ peak top intensity of the block copolymer (A) or its hydrogenated product measured according to JIS K 7244-4 (1999), the better the vibration damping property etc. at that temperature. If it is 1.0 or more, sufficient vibration damping properties can be obtained in the actual usage environment. The peak top intensity of tan δ is preferably 1.0 or more, more preferably 1.5 or more, and still more preferably 1.9 or more.
Note that the peak top intensity of tan δ is the value of tan δ when the peak of tan δ reaches its maximum. Further, the peak top temperature of tan δ is the temperature at which the peak of tan δ is at its maximum. The peak top temperature of tan δ and the peak top intensity of tan δ of the block copolymer (A) or its hydrogenated product are specifically measured by the method described in the Examples. In order to keep these values within the above ranges, for example, the ratio of isoprene as a monomer constituting the polymer block (A-2) may be adjusted.

(Other resin components)
Examples of resin components other than the block copolymer (A) that may be contained in the thermoplastic resin composition (AC) constituting the vibration-damping layer (AL) include polyolefin resins, polyamide resins, polyester resins, styrene resins, acrylic resins, polyoxymethylene resins, ABS resins, polyphenylene sulfide, polyphenylene ether, polyurethane thermoplastic elastomers, polycarbonates, rubber materials, and elastomer materials. The resin composition may contain one or more of these.
In addition, the thermoplastic resin composition (AC) may contain, as a resin component other than the block copolymer (A), hydrogenated resins such as hydrogenated coumarone-indene resins, hydrogenated rosin resins, hydrogenated terpene resins, and alicyclic hydrogenated petroleum resins; tackifier resins such as aliphatic resins composed of olefin and diolefin polymers; and other polymers such as hydrogenated polyisoprene, hydrogenated polybutadiene, butyl rubber, polyisobutylene, and polybutene, within the scope of the invention.
When the thermoplastic resin composition (AC) contains a resin component other than the block copolymer (A), the content of the resin component other than the block copolymer (A) in the composition is preferably 50 mass% or less, although this is not particularly limited. In this case, the content of the block copolymer (A) in the composition is preferably 50 mass% or more, more preferably 60 mass% or more, even more preferably 80 mass% or more, particularly preferably 90 mass% or more, and most preferably 95 mass% or more, from the viewpoint of vibration damping properties.

(Additive)
Components other than resin components that may be included in the thermoplastic resin composition (AC) constituting the damping layer (AL) include, for example, antioxidants, ultraviolet absorbers, light stabilizers, heat shielding materials, and anti-blocking agents. , pigments, dyes, softeners, crosslinking agents, crosslinking aids, crosslinking accelerators, fillers, and other additives, but are not particularly limited to these. These can be used alone or in combination of two or more.

Examples of the antioxidant include phenolic antioxidants, phosphorus antioxidants, sulfur antioxidants, and the like.
As the ultraviolet absorber, in addition to benzotriazole-based ultraviolet absorbers, hindered amine-based ultraviolet absorbers, benzoate-based ultraviolet absorbers, triazine-based compounds, benzophenone-based compounds, malonic acid ester compounds, oxalic acid anilide compounds, etc. can also be used.
Examples of the light stabilizer include hindered amine light stabilizers.
Examples of the heat shielding material include materials in which resin or glass contains heat ray shielding particles having a heat ray shielding function, organic dye compounds having a heat ray shielding function, and the like. Examples of particles having a heat ray shielding function include particles of oxides such as tin-doped indium oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, tin-doped zinc oxide, and silicon-doped zinc oxide, and LaB ₆ (lanthanum hexaboride). Examples include particles of inorganic materials having a heat ray shielding function such as particles. In addition, examples of organic dye compounds having a heat ray shielding function include diimonium dyes, aminium dyes, phthalocyanine dyes, anthraquinone dyes, polymethine dyes, benzenedithiol type ammonium compounds, thiourea derivatives, thiol metal complexes, etc. can be mentioned.
Examples of the anti-blocking agent include inorganic particles and organic particles. Inorganic particles include oxides, hydroxides, sulfides, nitrides, and halogens of group IA, IIA, IVA, VIA, VIIA, VIIIA, IB, IIB, IIIB, and IVB elements. compounds, carbonates, sulfates, acetates, phosphates, phosphites, organic carboxylates, silicates, titanates, borates, and their hydrated compounds, as well as complex compounds and natural mineral particles centered on them. can be mentioned. Examples of the organic particles include fluororesins, melamine resins, styrene-divinylbenzene copolymers, acrylic resin silicones, and crosslinked products thereof.
Examples of the pigment include organic pigments and inorganic pigments. Examples of organic pigments include azo pigments, quinacridone pigments, and phthalocyanine pigments. Examples of inorganic pigments include titanium oxide, zinc oxide, zinc sulfide, carbon black, lead pigments, cadmium pigments, cobalt pigments, iron pigments, chromium pigments, ultramarine, and navy blue.
Examples of dyes include azo, anthraquinone, phthalocyanine, quinacridone, perylene, dioxazine, anthraquino, indolinone, isoindolino, quinoneimine, triphenylmethane, thiazole, nitro, and nitroso dyes. Dyes include:
Examples of softeners include hydrocarbon oils such as paraffinic, naphthenic and aromatic oils; vegetable oils such as peanut oil and rosin; phosphoric acid esters; low molecular weight polyethylene glycol; liquid paraffin; low molecular weight polyethylene, ethylene-α- Known softeners such as hydrocarbon-based synthetic oils such as olefin copolymerized oligomers, liquid polybutene, liquid polyisoprene or hydrogenated products thereof, liquid polybutadiene or hydrogenated products thereof, etc. can be used. These may be used alone or in combination of two or more.

Examples of the crosslinking agent include radical generators, sulfur and sulfur compounds.
Examples of the radical generator include dialkyl monoperoxides such as dicumyl peroxide, di-t-butyl peroxide, and t-butylcumyl peroxide; 2,5-dimethyl-2,5-di(t-butylperoxy)hexane; , 5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, bis(t-butyldioxyisopropyl)benzene, 1,1-bis(t-butylperoxy)-3,3,5-trimethyl Diperoxides such as cyclohexane and n-butyl-4,4-bis(t-butylperoxy)valerate; diacyl peroxides such as benzoyl peroxide, p-chlorobenzoyl peroxide, and 2,4-dichlorobenzoyl peroxide; t-butyl peroxybenzoate, etc. monoacylalkyl peroxides; percarbonates such as t-butylperoxyisopropyl carbonate; and organic peroxides such as diacyl peroxides such as diacetyl peroxide and lauroyl peroxide. These may be used alone or in combination of two or more. Among them, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane and dicumyl peroxide are preferred from the viewpoint of reactivity.
Examples of the sulfur compound include sulfur monochloride and sulfur dichloride.
Other crosslinking agents that can be used include phenolic resins such as alkylphenol resins and brominated alkylphenol resins; combinations of p-quinonedioxime and lead dioxide, and combinations of p,p'-dibenzoylquinonedioxime and trilead tetroxide. can do.

As the crosslinking aid, known crosslinking aids can be used, such as trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, triallyl trimellitate, triallyl 1,2,4-benzenetricarboxylate. Ester, triallylisocyanurate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, 1,10-decanediol dimethacrylate, polyethylene glycol dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene Polyfunctional monomers such as glycol dimethacrylate, divinylbenzene, glycerol dimethacrylate, 2-hydroxy-3-acryloyloxypropyl methacrylate; stannous chloride, ferric chloride, organic sulfonic acids, polychloroprene, chlorosulfonated Examples include polyethylene. One type of crosslinking aid may be used alone, or two or more types may be used in combination.

Examples of crosslinking accelerators include thiazoles such as N,N-diisopropyl-2-benzothiazole-sulfenamide, 2-mercaptobenzothiazole, and 2-(4-morpholinodithio)benzothiazole; diphenylguanidine, triphenylguanidine. guanidines such as butyraldehyde-aniline reactants, aldehyde-amine reactants or aldehyde-ammonia reactants such as hexamethylenetetramine-acetaldehyde reactants; imidazolines such as 2-mercaptoimidazoline; thiocarbanilide, diethylurea, dibutyl Thioureas such as thiourea, trimethylthiourea, diorthotolylthiourea; dibenzothiazyl disulfide; thiuram monosulfides or thiuram polysulfides such as tetramethylthiuram monosulfide, tetramethylthiuram disulfide, pentamethylenethiuram tetrasulfide; zinc dimethyldithiocarbamate , thiocarbamates such as zinc ethyl phenyl dithiocarbamate, sodium dimethyl dithiocarbamate, selenium dimethyl dithiocarbamate, and tellurium diethyldithiocarbamate; xanthate salts such as zinc dibutyl xanthate; and zinc white. One type of crosslinking accelerator may be used alone, or two or more types may be used in combination.

Examples of fillers include talc, clay, mica, calcium silicate, glass, glass hollow spheres, glass fibers, calcium carbonate, magnesium carbonate, basic magnesium carbonate, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, and boron. Zinc acid, dawsonite, ammonium polyphosphate, calcium aluminate, hydrotalcite, silica, diatomaceous earth, alumina, titanium oxide, iron oxide, zinc oxide, magnesium oxide, tin oxide, antimony oxide, barium ferrite, strontium ferrite, carbon black, Conductive materials such as graphite, carbon fiber, activated carbon, carbon hollow spheres, calcium titanate, lead zirconate titanate, silicon carbide, inorganic fillers such as mica, organic fillers such as wood flour and starch, carbon black, graphite, carbon nanotubes, etc. Examples include metal fillers such as fillers, silver powder, copper powder, nickel powder, tin powder, copper fibers, stainless steel fibers, aluminum fibers, and iron fibers.

There is no particular limit to the content of the additives contained in the vibration-damping layer (AL), and the content can be adjusted appropriately depending on the type of additive, etc. When the vibration-damping layer (AL) contains the additives, the content of the additives may be, for example, 50% by mass or less, 45% by mass or less, or 30% by mass or less, or 0.01% by mass or more, 0.1% by mass or more, or 1% by mass or more, relative to the total mass of the vibration-damping layer (AL).

(Method for producing block copolymer (A))
The block copolymer (A) can be produced, for example, by a solution polymerization method, an emulsion polymerization method, a solid phase polymerization method, or the like. Among these, solution polymerization is preferred, and known methods such as ionic polymerization such as anionic polymerization and cationic polymerization, and radical polymerization can be applied. Among these, anionic polymerization is preferred. In the anionic polymerization method, in the presence of a solvent, an anionic polymerization initiator, and optionally a Lewis base, an aromatic vinyl compound and at least one member selected from the group consisting of a conjugated diene compound and isobutylene are sequentially added, A block copolymer (A) is obtained, and if necessary, a coupling agent is added and reacted. Furthermore, a hydrogenated block copolymer can be obtained by hydrogenating the block copolymer (A).

As a method for producing the block copolymer (A), for example, a structural unit containing the above-mentioned alicyclic skeleton (X) in the main chain can be produced by polymerizing one or more conjugated diene compounds as monomers by an anionic polymerization method. Form a polymer block (A-2) having the following properties, add the monomer of the polymer block (A-1), and if necessary, sequentially add the monomer of the polymer block (A-1) and a conjugated diene compound. By doing so, a block copolymer (A) containing an alicyclic skeleton (X) can be obtained.
A known technique can be used to generate the alicyclic skeleton by the anionic polymerization method (see, for example, US Pat. No. 3,966,691). An alicyclic skeleton is formed at the end of the polymer due to monomer depletion, and by sequentially adding further monomers to this, polymerization can be restarted from the alicyclic skeleton. Therefore, whether or not the alicyclic skeleton is produced and its content can be adjusted by controlling the sequential addition time of monomers, the polymerization temperature, the type and amount of catalyst added, the combination of monomer and catalyst, and the like. Further, in the anionic polymerization method, an anionic polymerization initiator, a solvent, and, if necessary, a Lewis base can be used.

In the above method, examples of organolithium compounds that can be used as a polymerization initiator for anionic polymerization include methyllithium, ethyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, pentyllithium, etc. Examples of dilithium compounds that can be used as a polymerization initiator include naphthalenedilithium, dilithiohexylbenzene, etc.
Examples of the coupling agent include dichloromethane, dibromomethane, dichloroethane, dibromoethane, dibromobenzene, and phenyl benzoate.
The amounts of these polymerization initiators and coupling agents used are appropriately determined depending on the desired weight average molecular weight of the target block copolymer (A). Usually, initiators such as alkyllithium compounds and dilithium compounds are preferably used in an amount of 0.01 to 0.2 parts by mass per 100 parts by mass of the total of monomers such as aromatic vinyl compounds and conjugated diene compounds used in the polymerization, and when a coupling agent is used, it is preferably used in an amount of 0.001 to 0.8 parts by mass per 100 parts by mass of the total of the monomers.

There are no particular limitations on the solvent as long as it does not adversely affect the anionic polymerization reaction, and examples of the solvent include aliphatic hydrocarbons such as cyclohexane, methylcyclohexane, n-hexane, and n-pentane; and aromatic hydrocarbons such as benzene, toluene, and xylene. The polymerization reaction is usually carried out at a temperature of 0 to 100°C, preferably 10 to 70°C, for 0.5 to 50 hours, preferably 1 to 30 hours.

In addition, by adding a Lewis base as a cocatalyst (vinylating agent) during polymerization, the content of 3,4-bonds and 1,2-bonds (vinyl bond amount) in the polymer block (A-2) can be increased. or the content of the alicyclic skeleton (X) can be increased.
Examples of the Lewis base include ethers such as dimethyl ether, diethyl ether, tetrahydrofuran, and 2,2-di(2-tetrahydrofuryl)propane (DTHFP); ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, and tetraethylene glycol. Glycol ethers such as dimethyl ether; Amines such as triethylamine, N,N,N',N'-tetramethylenediamine, N,N,N',N'-tetramethylethylenediamine (TMEDA), N-methylmorpholine; sodium Sodium or potassium salts of aliphatic alcohols such as t-butyrate, sodium t-amylate or sodium isopentylate, or sodium or potassium salts of alicyclic alcohols such as dialkyl sodium cyclohexanolate, e.g. sodium mentholate. metal salts; and the like.
Among the Lewis bases mentioned above, it is preferable to use tetrahydrofuran and DTHFP from the viewpoint of vibration damping properties and thermal stability. In addition, DTHFP can have a high vinyl bond content, easily achieve a high hydrogenation rate without using an excessive amount of hydrogenation catalyst, and can achieve both better vibration damping and thermal stability. It is more preferable to use
These Lewis bases can be used alone or in combination of two or more.

The amount of Lewis base added is determined by the extent to which the vinyl bond amount of the isoprene unit and/or butadiene unit constituting the polymer block (A-2) is controlled when the polymer block (A-2) contains a structural unit derived from isoprene and/or butadiene in particular. Therefore, the amount of Lewis base added is not strictly limited, but is preferably used within the range of usually 0.1 to 1,000 mol, preferably 1 to 100 mol, per gram atom of lithium contained in the alkyllithium compound or dilithium compound used as a polymerization initiator.
After polymerization has been carried out by the above-mentioned method, the polymerization reaction can be terminated by adding an active hydrogen compound such as an alcohol, a carboxylic acid, or water to obtain the block copolymer (A).

After polymerization is carried out by the method described above, active hydrogen compounds such as alcohols, carboxylic acids, and water are added to stop the polymerization reaction. Thereafter, a hydrogenated copolymer can be obtained by performing a hydrogenation reaction (hydrogenation reaction) in an inert organic solvent in the presence of a hydrogenation catalyst. The hydrogenation reaction is performed at a hydrogen pressure of 0.1 to 20 MPa, preferably 0.5 to 15 MPa, more preferably 0.5 to 5 MPa, and a reaction temperature of 20 to 250°C, preferably 50 to 180°C, more preferably 70°C. It can be carried out at ~180°C for a reaction time of usually 0.1 to 100 hours, preferably 1 to 50 hours.
From the viewpoint of carrying out the hydrogenation reaction of the polymer block (A-2) while suppressing the nuclear hydrogenation of the aromatic vinyl compound, examples of hydrogenation catalysts include Raney nickel; transition metal compounds and alkyl aluminum compounds; Examples include Ziegler catalysts in combination with lithium compounds, metallocene catalysts, and the like. From the same viewpoint as above, Ziegler-based catalysts are preferred, Ziegler-based catalysts consisting of a combination of a transition metal compound and an alkyl aluminum compound are more preferred, and Ziegler-based catalysts (Al/ Ni-based Ziegler catalyst) is more preferred.

The hydrogenated block copolymer thus obtained can be obtained by pouring the polymerization reaction liquid into methanol or the like to solidify it, followed by heating or drying under reduced pressure, or by pouring the polymerization reaction liquid into hot water together with steam to remove the solvent by azeotropy (so-called steam stripping), followed by heating or drying under reduced pressure.

(Method for producing thermoplastic resin composition (AC))
When using the block copolymer (A) or its hydrogenated product alone as the thermoplastic resin composition (AC), the block copolymer (A) or its hydrogenated product obtained by the above-mentioned production method. can be used as is as a thermoplastic resin composition (AC).
When obtaining a thermoplastic resin composition (AC) containing a block copolymer (A) or its hydrogenated product and a resin component other than the block copolymer (A), there are no particular restrictions on the manufacturing method. A known method can be used. For example, it may be produced by mixing the block copolymer (A) or its hydrogenated product and other resin components using a mixer such as a Henschel mixer, a V blender, a ribbon blender, a tumbler blender, or a conical blender. , or by mixing them and then melt-kneading them using a single-screw extruder, twin-screw extruder, kneader, or the like.
As the thermoplastic resin composition (AC), a block copolymer (A) or its hydrogenated product containing an additive is used, or a block copolymer (A) or its hydrogenated product and a block copolymer are used. Even when resin components other than (A) and additives are included, a thermoplastic resin composition (AC) can be obtained by mixing these components with the above-mentioned mixer or melting and kneading them with the above-mentioned device after mixing. can be manufactured.

<Constraint Layer (BL)>
The constraining layer (BL) is a layer that imparts appropriate rigidity to the laminate obtained by attaching the vibration-damping material to a metal plate and has a function of assisting the vibration-damping layer in exhibiting vibration-damping properties. The constraining layer (BL) is made of a material different from the vibration-damping layer (AL) and has a tensile storage modulus at least higher than that of the vibration-damping layer (AL).
The constraining layer (BL) according to the embodiment of the present invention is made of a thermoplastic resin composition (BC). Since the constraining layer (BL) is made of a thermoplastic resin composition (BC), the weight of the vibration-damping material can be reduced compared to a vibration-damping material used in a vibration-damping steel plate having a structure of "steel plate/vibration-damping layer/steel plate."
The thermoplastic resin composition (BC) constituting the constraining layer (BL) may be composed of only a resin component, or may contain various additives other than the resin component. Components other than the resin component that may be contained in the thermoplastic resin composition (BC) will be described later.

As defined in the above condition (3), the constraint layer (BL) has a ratio H(BL) of the thickness H(BL) of the constraint layer (BL) to the thickness H(AL) of the damping layer (AL). )/H(AL) is 3 to 200. When the thickness H (BL) of the restraining layer (BL) has the above relationship with the thickness H (AL) of the damping layer (AL), the restraining layer (BL) is The damping material becomes sufficiently thick and has sufficient rigidity while being lightweight.
The above H(BL)/H(AL) is preferably 5 to 150 from the viewpoint of moldability, more preferably 8 to 100, still more preferably 10 to 60, and even more preferably from the viewpoint of vibration damping properties. Preferably it is 13-40.

In addition, when the damping material has a structure in which a damping layer (AL) and a constraint layer (BL) are repeatedly laminated, H(BL) in the above H(BL)/H(AL) is a plurality of constraints. H(AL) is the total thickness of the layers (BL), and H(AL) is the total thickness of the plural damping layers (AL). For example, in the case of the damping material 101 shown in FIG. 2(A), H(AL) is the thickness H (AL1) of the first damping layer and the thickness H (AL2) of the second damping layer. The sum is H(AL)=H(AL1)+H(AL2). In addition, H (BL) is the sum of the thickness H (BL1) of the first restraining layer, the thickness H (BL2) of the second restraining layer, and the thickness H (BL3) of the third restraining layer, that is, , H(BL)=H(BL1)+H(BL2)+H(BL3).
The thicknesses H (AL) and H (BL) control the molding conditions (for example, the discharge amount from an extrusion molding machine in extrusion molding) when molding the damping layer (AL) and the constraint layer (BL), for example. By doing so, the thickness H (AL) described above or the thickness H (BL) described below can be adjusted, and thereby the above relationship can be achieved.

The thickness H (BL) of the constraining layer (BL) is preferably 0.4 mm or more, preferably 0.6 mm or more, and preferably 0.8 mm or more from the viewpoint of ensuring mechanical strength and damping properties. From the viewpoint of preventing the weight and thickness of the damping material from becoming excessively large, the thickness is preferably 5 mm or less, more preferably 4 mm or less, and still more preferably 3 mm or less. In other words, the thickness H (BL) of the constraining layer (BL) is preferably 0.4 to 5 mm from the viewpoint of ensuring mechanical strength and damping properties.

The constraining layer (BL) can be a layer co-extruded with the vibration-damping layer (AL) in order to simplify the structure of the vibration-damping material and facilitate the production of the vibration-damping material.
If the constraining layer (BL) is a layer co-extruded with the vibration-damping layer (AL), the vibration-damping material can be constructed with a minimum number of layers, in which the vibration-damping layer is closely fixed to the constraining layer, and the structure of the vibration-damping material can be simplified. In addition, there is no need to provide other layers to fix the vibration-damping layer to the constraining layer, and the vibration-damping material can be manufactured easily and quickly. In addition, since the structure of the vibration-damping material is simple, it is easy to make the vibration-damping material exhibit the intended vibration-damping performance.

The constraining layer (BL) can also be thermally fused to the damping layer (AL).
If the constraining layer (BL) is thermally fused to the damping layer (AL), the structure of the damping material can be simplified, as in the case of coextrusion described above, and the intended damping performance can be achieved. It becomes easier to demonstrate. Further, there is no need to provide an adhesive layer or the like, and the damping material can be easily manufactured.

(Thermoplastic resin composition (BC))
The thermoplastic resin composition (BC) is a material that can provide high mechanical properties to the constraining layer (BL). The thermoplastic resin composition (BC) is a different type of composition from the thermoplastic resin composition (AC), and has a higher tensile storage modulus than at least the thermoplastic resin composition (AC). The thermoplastic resin composition (BC) may be made of a single resin or may contain a plurality of specific resins.
As defined in the above condition (2), at least one of the glass transition temperature Tg and melting point Tm of the thermoplastic resin composition (BC) is 100° C. or higher.
When the Tg or Tm of the thermoplastic resin composition (BC) is within the above range, the thermoplastic resin composition (BC) generally has good mechanical properties (e.g., tensile storage modulus and loss modulus). become. Therefore, the mechanical properties of the constrained layer (BL) can be improved.
At least one of the glass transition temperature and melting point of the thermoplastic resin composition (BC) is preferably 100°C or higher, more preferably 120°C or higher, and even more preferably 140°C or higher, from the viewpoint of mechanical strength, and From the viewpoint of moldability, the temperature is preferably 350°C or lower, more preferably 300°C or lower, and even more preferably 280°C or lower. In other words, at least one of the glass transition temperature and melting point of the thermoplastic resin composition (BC) is preferably 100 to 350°C from the viewpoint of mechanical strength and moldability.
In addition, in this specification, Tg and Tm of the thermoplastic resin composition (BC) are the temperature at which a baseline shift occurs in a DSC curve created using a differential scanning calorimeter (DSC), and the endothermic temperature is Tg. The temperature at which the peak was observed is defined as Tm, and specifically, it is measured by the method described in the Examples. Even when the thermoplastic resin composition (BC) contains infusible additives among the additives described below, the temperature measured by the above method is taken as the Tg and Tm of the thermoplastic resin composition (BC).

20, which is measured by performing a dynamic viscoelasticity test using tensile vibration of a thermoplastic resin composition (BC) in accordance with JIS K7244-4 (1999) at a strain amount of 0.2% and a frequency of 10 Hz. The tensile storage modulus E' (BC) at °C is preferably 1,000 MPa or more, more preferably 1,500 MPa or more, even more preferably 2,000 MPa or more, from the viewpoint of vibration damping properties of the laminate, and From the viewpoint of workability, the pressure is preferably 100,000 MPa or less, more preferably 50,000 MPa or less, still more preferably 30,000 MPa or less. In other words, the tensile storage modulus E'(BC) is preferably 1,000 to 100,000 MPa from the viewpoint of vibration damping properties and workability of the laminate.

Thermoplastic resin composition (BC) at 20°C measured by performing a dynamic viscoelasticity test using tensile vibration at a strain amount of 0.2% and a frequency of 10Hz in accordance with JIS K7244-4 (1999) The loss modulus E'' (BC) is preferably 10 MPa or more, more preferably 30 MPa or more, even more preferably 50 MPa or more, from the viewpoint of vibration damping properties of the laminate, and from the viewpoint of mechanical properties, preferably is 10,000 MPa or less, more preferably 5,000 MPa or less, even more preferably 1,000 MPa or less. In other words, the loss modulus E'' (BC) is preferably 10 to 10,000 MPa from the viewpoint of achieving both damping properties and mechanical properties.

The tensile storage modulus E'(AC) of thermoplastic composition (AC) and the tensile storage modulus E'(BC) of thermoplastic composition (BC) at 20°C, measured in accordance with JIS K7244-4 (1999) by performing a dynamic viscoelasticity test using tensile vibration at a strain of 0.2% and a frequency of 10 Hz, preferably satisfies the relationship E'(BC)/E'(AC) ≧ 50, more preferably E'(BC)/E'(AC) ≧ 100, and even more preferably E'(BC)/E'(AC) ≧ 120 from the viewpoint of the vibration damping properties of the laminate, and preferably satisfies the relationship E'(BC)/E'(AC) ≦ 100,000, more preferably E'(BC)/E'(AC) ≦ 10,000, and even more preferably E'(BC)/E'(AC) ≦ 10,000 from the viewpoint of the formability of the laminate. In other words, from the viewpoint of vibration damping and moldability of the laminate, the tensile storage modulus E'(BC) preferably satisfies the relationship 100,000 ≧ E'(BC)/E'(AC) ≧ 50.

From the viewpoint of moldability and adhesion to the damping layer (AL), the thermoplastic resin composition (BC) preferably contains at least one of an olefin resin and a polyamide resin, and more preferably contains an olefin resin. .

Examples of the olefin resin include polypropylene, polyethylene, polymethylpentene, ethylene-vinyl acetate copolymer, and combinations of two or more of these resins.
Examples of the polypropylene include homopolypropylene, block polypropylene which is a block copolymer with an α-olefin such as ethylene, and random polypropylene which is a random copolymer with an α-olefin such as ethylene.
Examples of the polyethylene include high density polyethylene, medium density polyethylene, low density polyethylene, and linear low density polyethylene.
Examples of the polymethylpentene include homopolymers of 4-methyl-1-pentene and copolymers having structural units derived from 4-methyl-1-pentene and structural units derived from an α-olefin having 2 to 20 carbon atoms (excluding 4-methyl-1-pentene).
The ethylene-vinyl acetate copolymer is not particularly limited as long as it is a resin in which ethylene is copolymerized with acetic acid as a comonomer, and those having various vinyl acetate group contents (VA contents) can be used.
Furthermore, homopolymers or copolymers of α-olefins, copolymers of propylene and/or ethylene with α-olefins, etc. can also be used as the polyolefin resin (B).
Examples of the α-olefin include α-olefins having 20 or less carbon atoms, such as 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 3-methyl-1-pentene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-eicosene, and one or more of these may be used.

Examples of the polyamide resins include polyamide 6, polyamide 6.6, polyamide 6.10, polyamide 11, polyamide 12, polyamide 6.12, polyhexamethylenediamine terephthalamide, polyhexamethylenediamine isophthalamide, and xylene group-containing polyamides.

(Additive)
Examples of resin materials other than the thermoplastic resin component (BC) that can be contained in the constraining layer (BL) include additives such as antioxidants, ultraviolet absorbers, light stabilizers, heat shielding materials, antiblocking agents, pigments, dyes, softeners, crosslinking agents, crosslinking assistants, and crosslinking accelerators, but are not particularly limited to these. These can be used alone or in combination of two or more.
As these additives, the same ones as those explained in the vibration-damping layer (AL) can be used.

In addition, the constraining layer (BL) contains fillers, reinforcing materials, lubricants, antistatic agents, flame retardants, foaming agents, water repellents, waterproofing agents, conductivity imparting agents, thermal conductivity imparting agents, and electromagnetic shielding properties. The composition may contain additives such as a fluorescent agent, a fluorescent agent, and an antibacterial agent.
As the filler, the same filler as that described for the damping layer (AL) above can be used.
A commercially available resin material in which additives are blended with resin, such as glass fiber reinforced resin, can also be used as the thermoplastic resin composition (BC).

(Method for producing thermoplastic resin composition (BC))
The method for producing the thermoplastic resin composition (BC) is not particularly limited, and a known method can be adopted. For example, the thermoplastic resin composition (BC) can be produced by mixing a single resin having at least one of Tg and Tm of 100° C. or more, or a specific plurality of types of resins, using a mixer such as a Henschel mixer, a V blender, a ribbon blender, a tumbler blender, or a conical blender, or by mixing the resins and then melt-kneading them with a single-screw extruder, a twin-screw extruder, a kneader, or the like.
When a thermoplastic resin composition (BC) containing a resin and an additive is used, the thermoplastic resin composition (BC) can be produced by mixing these components in the mixer described above, or by melt-kneading the components in the device described above after mixing.

<Manufacturing method of damping material>
The above-mentioned damping material is preferably made by co-extruding the damping layer (AL) and the constraining layer (BL) from the viewpoint of facilitating the production of the damping material and simplifying the structure of the damping material. Manufactured by forming.
Specifically, a thermoplastic resin composition (AC) and a thermoplastic resin composition (BC) are respectively melted, and other components such as additives are added as necessary, and the mixture is heated in a Henschel mixer. , manufactured by mixing using a mixer such as a V blender, ribbon blender, tumbler blender, conical blender, etc., or after the mixing, melt-kneading with a single screw extruder, twin screw extruder, kneader, etc. A damping material can be produced by co-extruding it in layers from an injection molding machine and pressing it with a pair of rollers.

In another aspect of the method for manufacturing a damping material, the damping material is manufactured by forming a damping layer (AL) and a restraining layer (BL), respectively, and then laminating and heat-sealing them.
Specifically, a thermoplastic resin composition (AC) and a thermoplastic resin composition (BC) are each molded into a sheet shape, and then the two are stacked and pressed with a pair of heated rollers. A damping material can be produced by thermally melting at least one of them and thermally fusing it to the other.

[Laminated body]
A laminate according to an embodiment of the present invention includes the damping material described above and a metal plate laminated on the damping material.
When the vibration damping material includes only one structure in which a vibration damping layer (AL) and a restraining layer (BL) are laminated as shown in FIG. As shown in (B), the damping material includes the damping material and a metal plate laminated on the surface of the damping material opposite to the constraining layer (BL).
As shown in FIG. 2(A), the vibration damping material has a structure in which a vibration damping layer (AL) and a constraint layer (BL) are repeatedly laminated, and the constraint layer (BL) is formed on the upper and lower surfaces. BL), the resulting laminate has the damping material and a metal plate laminated on the constraining layer (BL) of the damping material as shown in FIG. 2(B). include.
When the damping material has a structure in which a damping layer (AL) and a restraining layer (BL) are repeatedly laminated, and the damping layer (AL) is located on the top or bottom surface, The resulting laminate includes the damping material and a metal plate laminated on the damping layer (AL) of the damping material.

Examples of the metal plates include stainless steel plates, cold-rolled steel plates, alloyed galvanized steel plates, SECC (bonded steel plates), and the like.

In a laminate in which a constraining layer (BL) located on the upper or lower surface of a vibration-damping material is attached to a metal plate, such as the laminate 201 shown in Figure 2 (B), it is preferable to provide an intermediate layer between the constraining layer (BL) and the metal plate to adhere the two to each other.
The intermediate layer may be, for example, an adhesive layer or a bonding layer formed by applying an adhesive material or a bonding material to at least one of the constraining layer (BL) and the metal layer before attaching the constraining layer (BL) to the metal layer. In addition, by using a metal plate on which an adhesive auxiliary layer or a skin layer is formed, the auxiliary layer or the skin layer may be used as the intermediate layer.
Examples of the intermediate layer include polyvinyl acetal resin, ionomer, ethylene-vinyl acetate copolymer, urethane resin, polyamide resin, acrylic resin, etc. The intermediate layer may contain an adhesion regulator such as an alkali metal salt or an alkaline earth metal salt, or a plasticizer.

[Method for improving vibration damping performance]
A method for improving damping properties according to an embodiment of the present invention is a method for improving damping properties by attaching the damping material to a metal plate to improve the damping properties of the metal plate.
Here, when the damping material includes only one structure in which a damping layer (AL) and a constraint layer (BL) are laminated as shown in FIG. In this method, the surface of the vibration damping material opposite to the restraining layer (BL) (that is, the vibration damping layer (AL)) is attached to the metal plate.
When attaching the damping material to the metal plate, place the damping material on the metal plate so that the damping layer (AL) of the damping material is in contact with the surface of the metal plate, and then apply a heat roller to the metal plate. The damping material can be attached to a metal plate by a method such as pressing with a pair of rollers.
When a damping material is attached to a metal plate in this way, it becomes a laminate having the structure of "restraint layer (BL)/damping layer (AL)/metal plate", which improves the vibration damping properties of the metal plate. can. Since the constraining layer (BL) is made of the thermoplastic resin composition (BC), it is possible to suppress the weight of the entire laminate from increasing. Since the damping material and the metal plate are directly bonded by thermocompression, the structure is simple and it is easy to impart intended damping properties to the resulting laminate.
In addition, compared to the method of thermocompression bonding the damping material and the metal plate, the number of layers constituting the laminate increases, but the method of attaching the damping material to the metal plate via an adhesive layer or adhesive layer It can also be adopted.
In addition, there are cases in which the damping layer (AL) and the restraint layer (BL) are repeatedly laminated in multiple layers, and the damping layer (AL) is located on the top or bottom surface of the damping material. , the damping layer (AL) can be placed so as to be in contact with the surface of the metal plate, and the damping material can be attached to the metal plate in the same manner as described above.

When the vibration-damping material has a structure in which the vibration-damping layer (AL) and the constraining layer (BL) are repeatedly laminated as shown in Fig. 2 (A) and the constraining layer (BL) is located on the upper and lower surfaces, an intermediate layer is provided on at least one of the constraining layer (BL) and the metal plate in order to adhere them to each other. A metal plate on which an adhesive auxiliary layer and a skin layer are formed may be prepared in advance and used.
Then, the constraint layer (BL) of the vibration-damping material is placed opposite the surface of the metal plate, the two are overlapped with the intermediate layer interposed therebetween, and the vibration-damping material can be attached to the metal plate by a method such as pressing with a pair of rollers while heating as necessary.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples in any way.

[Manufacture example 1]
<Production of hydrogenated product TPE-1 of block copolymer (A)>
In a pressure-resistant container that has been purged with nitrogen and dried, 50 kg of cyclohexane (solvent) dried with molecular sieves A4, and 0.101 kg of a cyclohexane solution of sec-butyllithium (sec-butyl lithium) with a concentration of 10.5% by mass as an anionic polymerization initiator The actual amount of lithium added: 10.6 g) was charged.
After raising the temperature in the pressure container to 50°C, 1.7 kg of styrene (1) was added and polymerized for 30 minutes, the temperature was lowered to 40°C, 0.29 kg of tetrahydrofuran (THF) was added, and 13.0 kg of isoprene was added. 3 kg was added over 5 hours and polymerized for 1 hour. Thereafter, the temperature was raised to 50°C, 1.7 kg of styrene (2) was added, polymerized for 30 minutes, methanol was added to stop the reaction, and the reaction mixture containing the polystyrene-polyisoprene-polystyrene triblock copolymer I got it.
A Ziegler hydrogenation catalyst formed from nickel octylate and trimethylaluminum was added to the reaction solution in a hydrogen atmosphere, and the mixture was reacted at a hydrogen pressure of 1 MPa and a temperature of 80° C. for 5 hours. After the reaction solution was allowed to cool and depressurize, the catalyst was removed by washing with water, and the hydrogenated product (TPE-1) of a polystyrene-polyisoprene-polystyrene triblock copolymer was obtained by vacuum drying. Ta.

[Production Examples 2 to 5]
<Production of hydrogenated products TPE-2 to 5 of block copolymer (A)>
Hydrogenated block copolymers TPE-2 to TPE-5 were produced in the same manner as in Production Example 1, except that the raw materials and the amounts used were as shown in Table 1.

<Physical properties of hydrogenated block copolymer>
Physical properties of hydrogenated block copolymers TPE-1 to TPE-5 were measured according to the following measurement method. The results are shown in Table 2.

(Content of polymer block (A-1))
The hydrogenated block copolymer was dissolved in CDCl ₃ and subjected to ¹ H-NMR measurement [equipment: "ADVANCE 400 Nano bay" (manufactured by Bruker), measurement temperature: 30°C], and the weight was determined from the peak intensity derived from styrene. The content of the combined block (A-1) was calculated.

(Amount of vinyl bonds in polymer block (A-2))
The block copolymer before hydrogenation was dissolved in CDCl ₃ and subjected to ¹ H-NMR measurement [device: "ADVANCE 400 Nano bay" (manufactured by Bruker), measurement temperature: 30°C]. Ratio of the peak area corresponding to the 3,4-bond unit and 1,2-bond unit in the isoprene structural unit and the 1,2-bond unit in the butadiene structural unit to the total peak area of the structural unit derived from isoprene and/or butadiene. From this, the amount of vinyl bonds (total content of 3,4-bond units and 1,2-bond units) was calculated.

(Hydrogenation rate of polymer block (A-2))
The hydrogenated block copolymer was dissolved in CDCl ₃ and subjected to ¹ H-NMR measurement [equipment: "ADVANCE 400 Nano bay" (manufactured by Bruker), measurement temperature: 30°C] to determine the residual olefin-derived isoprene or butadiene. The hydrogenation rate was calculated from the peak area and the peak area ratio derived from ethylene, propylene, and butylene.

(Weight average molecular weight (Mw))
The weight average molecular weight (Mw) of the block copolymer and hydrogenated block copolymer in terms of polystyrene was determined by gel permeation chromatography (GPC) measurement under the following conditions.
<<GPC measurement equipment and measurement conditions>>
・Device: GPC device “HLC-8020” (manufactured by Tosoh Corporation)
- Separation column: Two "TSKgel G4000HX" manufactured by Tosoh Corporation were connected in series.
・Eluent: Tetrahydrofuran ・Eluent flow rate: 0.7mL/min
・Sample concentration: 5mg/10mL
・Column temperature: 40℃
・Detector: Differential refractive index (RI) detector ・Calibration curve: Created using standard polystyrene

(Peak top temperature and peak top intensity of loss tangent (tanδ))
Measurements were performed according to JIS K 7244-4 (1999). Specifically, the obtained hydrogenated block copolymer was pressed at 230° C. for 3 minutes to produce a sheet measuring 50 mm long x 30 mm wide x 1 mm thick. This sheet is cut out into a sample with a length of 30 mm x width of 5 mm x thickness of 1 mm, and is measured using a NETZSCH DMA242 at a measurement temperature of -80°C to 100°C, a strain amount of 0.2%, and a frequency of 10 Hz. By this, the peak top temperature and peak top intensity of loss tangent (tan δ) were measured.

[Examples 1 to 10, Comparative Examples 1 to 3]
<Manufacture of damping material and measurement of its physical properties>
The above hydrogenated block copolymer TPE-1TPE-5 was used as a thermoplastic resin composition (AC) for forming a damping layer (AL). In addition, polypropylene (PP) (“E-200GP” manufactured by Prime Polymer Co., Ltd.), glass fiber reinforced polypropylene (GFPP) (“R-300G” manufactured by Prime Polymer Co., Ltd.), glass fiber reinforced nylon 6 (GFPA6) (BASF Co., Ltd.) "B3EG6") was used as the thermoplastic resin composition (BC) for forming the constraining layer (BL).
In Example 1, the thermoplastic resin composition (AC) for the damping layer (AL) was produced using a vented single-screw extruder with a screw diameter of 50 mm at a discharge rate of 2 kg/hour. The thermoplastic resin composition (BC) for the constrained layer (BL) was introduced into a die (multi-manifold type: width 500 mm) using a vented single-screw extruder with a screw diameter of 65 mm, at a discharge rate of 80 kg/hour. It was introduced into the T-die under the following conditions.
The molded product coextruded from the T-die is nipped between two mirror-finished metal rolls, one at 50°C and the other at 60°C, to form a damping layer (AL)/constraint layer (BL) (thickness: 50 μm/2000 μm). ) was fabricated as a two-layer damping material (total thickness 2,050 μm).
Damping materials of Examples 2 to 10 and Comparative Example 3 were produced in the same manner as in Example 1, except that the discharge rate of the vented single-screw extruder was changed as shown in Table 3. Note that in Comparative Examples 1 and 2, no constraint layer (BL) was provided.

(Glass transition temperature and melting point)
The Tg of the thermoplastic resin composition (AC) and the Tg and Tm of the thermoplastic resin composition (BC) were measured at 10°C from -100°C to 350°C using TA Instruments DSC250. /min, and find the shift position of the baseline of the DSC curve (specifically, the intersection of the midpoint line of the baseline before and after the specific heat change appears and the DSC curve). Tg was defined as Tg, and the peak temperature of the endothermic peak was defined as Tm.

(Loss tangent (tan δ), tensile storage modulus E', loss modulus E'')
The above hydrogenated block copolymer for the vibration-damping layer (AL) and each thermoplastic resin composition for the constraining layer (BL) were pressed at a temperature of 230°C and a pressure of 10 MPa for 3 minutes using a press molding device to produce a sheet with a thickness of 1 mm, and the sheet was cut into a size of 30 mm x 5 mm to prepare a test piece.
In accordance with JIS K7244-4 (1999), a dynamic viscoelasticity test was performed in a tensile mode using a dynamic viscoelasticity device "DMA242" (manufactured by NETZSCH) while raising the temperature from -80°C to 100°C at a rate of 3°C/min under conditions of a strain of 0.2% and a frequency of 10 Hz, thereby measuring tan δ, tensile storage modulus E', and loss modulus E'' at 20°C.

<Production of Laminate and Measurement of Its Physical Properties>
A laminate having a structure of "constraint layer (BL)/damping layer (AL)/adhesive layer/steel plate" was obtained by bonding a SECC (bonded steel plate) having a length of 200 mm, a width of 10 mm, and a thickness of 0.8 mm to the sheet-like vibration-damping material prepared above with ARON ALPHA EXTRA manufactured by Toagosei Co., Ltd., so that the vibration-damping layer (AL) was on the steel plate side. However, for Comparative Examples 1 and 2, a non-constraint type laminate having a structure of "damping layer (AL)/adhesive layer/steel plate" was used. The thickness of the adhesive layer was 0.05 mm.

(Loss factor of laminate)
A contact tip was attached to the center of the laminate prepared above using an adhesive mainly composed of α-cyanoacrylate to prepare a sample, which was then set in a loss factor measurement system (Brüel & Kjær Vibrator 4809; Impedance Head 8001; Charge Converter 2647A). Specifically, the steel plate side of the center of the sample was fixed to the tip of the vibration force detector built into the impedance head of the vibrator of the above device. Then, a damping test of the measurement sample was performed by the central vibration method by applying vibration to the center of the sample in the frequency range of 0 to 8,000 Hz, and the vibration force at the center and the acceleration signal representing the acceleration waveform were detected. Measurements were performed on each sample at a temperature of 20°C.
The mechanical impedance at the excitation point (the center of the laminate to which vibration was applied) was calculated based on the obtained excitation force and the velocity signal obtained by integrating the acceleration signal. An impedance curve was then created with the horizontal axis representing frequency and the vertical axis representing the mechanical impedance, and the loss factor of the laminate at 20°C was calculated from the full width at half maximum of the second peak (2nd mode) counting from the low frequency side.
The measurement results are shown in Table 3 below.

As is clear from Table 3, the laminates of Examples 1 to 10 have larger loss coefficients at 20°C and are superior in vibration damping properties compared to the laminates of Comparative Examples 1 and 2, which do not have a constraining layer (BL).
Moreover, the laminates of Examples 1 to 10 have a larger loss factor at 20° C. and are excellent in vibration damping properties, even compared to the laminate of Comparative Example 3, that is, a laminate using a hydrogenated block copolymer having a Tg lower than −40° C. and a tan δ of less than 0.3 at 20° C. as a vibration damping layer (AL).

The damping material and laminate of the present invention can be used for automobile casings, various parts mounted on automobiles, housings thereof, and the like. In addition, in the field of home appliances, TVs, various recorders such as Blu-ray recorders and HDD recorders, projectors, game consoles, digital cameras, home videos, antennas, speakers, electronic dictionaries, IC recorders, fax machines, copy machines, telephones, door phones, and rice cookers. , microwave oven, microwave oven, refrigerator, dishwasher, dish dryer, IH cooking heater, hot plate, vacuum cleaner, washing machine, charger, sewing machine, iron, dryer, electric bicycle, air purifier, water purifier, electric toothbrush It can be used in various electrical products such as lighting equipment, air conditioners, outdoor units of air conditioners, dehumidifiers, and humidifiers.

AL, AL1, AL2: Damping layer BL, BL1, BL2, BL3: Restriction layer 10: Metal plate 100, 101: Damping material 200, 201: Laminated body

Claims (23)

A damping material comprising a damping layer (AL) and a restraining layer (BL) laminated on the damping layer (AL),
The damping layer (AL) includes a polymer block (A-1) containing a structural unit derived from an aromatic vinyl compound and a polymer block (A-2) containing a structural unit derived from a conjugated diene compound. consisting of a thermoplastic resin composition (AC) containing a block copolymer (A) having
The constraining layer (BL) is made of a thermoplastic resin composition (BC),
A damping material that satisfies the following conditions (1) to (3).
(1) The glass transition temperature of the thermoplastic resin composition (AC) is -40 to +30°C.
(2) At least one of the glass transition temperature and melting point of the thermoplastic resin composition (BC) is 100°C or higher.
(3) The ratio H(BL)/H(AL) of the thickness H(BL) of the constraining layer (BL) to the thickness H(AL) of the damping layer (AL) is 3 to 200. The vibration damping material according to claim 1, wherein the glass transition temperature of the block copolymer (A) is -40 to +30°C. The damping material according to claim 1 or 2, wherein the content of the polymer block (A-1) in the block copolymer (A) is 22% by mass or less. The vibration damping material according to any one of claims 1 to 3, wherein the weight average molecular weight of the block copolymer (A) is 30,000 to 200,000. The vibration damping material according to any one of claims 1 to 4, wherein the block copolymer (A) is a hydrogenated product, and the hydrogenation rate of the polymer block (A-2) is 85 mol % or more. Claim 1, wherein the polymer block (A-2) in the block copolymer (A) has a structural unit containing one or more alicyclic skeletons (X) in the main chain represented by the following formula (X). The damping material according to any one of items 5 to 5.

(In the above formula (X), R ¹ to R ³ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 11 carbon atoms, and a plurality of R ¹ to R ³ may be the same or different.) The damping material according to claim 6, wherein the alicyclic skeleton (X) includes an alicyclic skeleton (X') in which at least one of R ¹ to R ³ is a methyl group. The damping material according to claim 6 or 7, wherein the polymer block (A-2) contains the alicyclic skeleton (X) or (X') in an amount of 1 mol% or more. The vibration damping material according to any one of claims 1 to 8, wherein the thermoplastic composition (AC) has a tensile storage modulus E'(AC) of 100 MPa or less at 20°C, as measured by a dynamic viscoelasticity test using tensile vibration at a strain of 0.2% and a frequency of 10 Hz in accordance with JIS K7244-4 (1999). The vibration damping material according to any one of claims 1 to 9, wherein the loss tangent tanδ at 20°C of the thermoplastic composition (AC) is 0.3 or more, as measured by performing a dynamic viscoelasticity test using tensile vibration at a strain of 0.2% and a frequency of 10 Hz in accordance with JIS K7244-4 (1999). The vibration-damping material according to any one of claims 1 to 10, wherein the thickness H(AL) of the vibration-damping layer (AL) is 0.3 mm or less. 20, which is measured by performing a dynamic viscoelasticity test using tensile vibration of a thermoplastic resin composition (BC) in accordance with JIS K7244-4 (1999) at a strain amount of 0.2% and a frequency of 10 Hz. The damping material according to any one of claims 1 to 11, having a tensile storage modulus E' (BC) at 1,000 MPa or more at °C. Thermoplastic resin composition (BC) at 20°C measured by performing a dynamic viscoelasticity test using tensile vibration at a strain amount of 0.2% and a frequency of 10Hz in accordance with JIS K7244-4 (1999) The damping material according to any one of claims 1 to 12, having a loss modulus E'' (BC) of 10 MPa or more. The vibration damping material according to any one of claims 1 to 13, wherein the thermoplastic resin composition (BC) contains at least one of an olefin resin and a polyamide resin. The damping material according to any one of claims 1 to 14, wherein the thickness H (BL) of the constraining layer (BL) is 0.4 mm or more. The vibration damping material according to any one of claims 1 to 15, wherein the tensile storage modulus E'(AC) of the thermoplastic composition (AC) and the tensile storage modulus E'(BC) of the thermoplastic composition (BC) at 20°C, as measured by a dynamic viscoelasticity test using tensile vibration at a strain of 0.2% and a frequency of 10 Hz in accordance with JIS K7244-4 (1999), satisfy the relationship E'(BC)/E'(AC) ≥ 50. The vibration-damping material according to any one of claims 1 to 16, wherein the ratio H(BL)/H(AL) of the thickness H(BL) of the constraining layer (BL) to the thickness H(AL) of the vibration-damping layer (AL) is 8 to 100. The vibration-damping material according to any one of claims 1 to 17, wherein the vibration-damping layer (AL) is a layer coextruded with the constraining layer (BL). The vibration-damping material according to any one of claims 1 to 17, which is formed by heat-sealing the vibration-damping layer (AL) and the constraining layer (BL). A method for producing a vibration-damping material according to any one of claims 1 to 19, in which the vibration-damping material is produced by co-extruding a vibration-damping layer (AL) and a constraining layer (BL). 20. The method for producing a damping material according to claim 1, wherein the damping layer (AL) and the constraining layer (BL) are formed, respectively, and then laminated and thermally fused. A method for manufacturing vibration damping materials. A laminate comprising the damping material according to any one of claims 1 to 19 and a metal plate laminated on the damping material. 20. A method for improving vibration damping properties, comprising attaching the damping material according to any one of claims 1 to 19 to a metal plate to enhance the damping properties of the metal plate.