JPH078903B2 - Damping material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a vibration damping material, and more specifically to a high temperature region, particularly 80 to 10
The present invention relates to a vibration damping material that exhibits excellent vibration damping performance near 0 ° C. and is useful as a high temperature vibration damping material for engine peripheral parts such as an oil pan.

[Prior Art] Conventionally, in order to suppress or prevent noise and vibration generated from various mechanical devices, electric devices, structures, and the like, a metal plate using a viscoelastic resin or resin composition as a damping material. There has been proposed or put into practical use a vibration-damping composite laminate in which the vibration-damping performance is expressed by utilizing the internal friction due to the shearing deformation of the vibration-damping material, which is laminated between the substrates. An example of such a damping material composition is disclosed in JP-A-54
JP-A-43251 or JP-A-54-43252 describes a composition containing polyisobutylene as a main component and a diene hydrocarbon polymer or cyclic olefin polymer and an inorganic filler. There is. Japanese Unexamined Patent Publication (Kokai) No. 57-34949 describes a damping material composed of an ethylene / vinyl acetate copolymer.

Japanese Unexamined Patent Publication No. 61-89842 discloses a damping material made of polyester or polyester and polyolefin having specific properties.

Further, although it is not described as a vibration damping material, it is disclosed in JP-A-55-123458.
The publication describes a composite laminate of amorphous polyethylene terephthalate and a metal using terephthalic acid as dicarboxylic acid component and a small amount of isophthalic acid.

Further, the same type of polyester that constitutes the vibration damping material of the present invention is described in JP-A-58-167617.

[Problems of conventional technology]

 Among the conventional techniques described above, JP-A-54-43251,
Disclosed in JP-A-54-43252 and JP-A-57-34949
The materials that have been subjected to vibration control do not have sufficient vibration damping properties, especially at high temperatures.
Poor performance, such as high temperature damping material around the engine
There is a problem that it can not be used. JP 61-89842
The one disclosed in Japanese Patent Publication has a relatively large elongation and is soft.
A non-crystalline polyester applied to a damping material.
In addition, in the description, terephthalic acid and isophthalic acid
As an example of a copolyester of
KODAR of Kodak Company PCTA resin A-150 is isophthalic acid
The content is as low as 25 mol%. Moreover, the temperature loss coefficient η
Has a very large effect, and the temperature range showing a high η value is extremely
Narrow at the edge. As described in JP-A-55-123458,
There is no suggestion on its use as a damping material,
Amorphous polyethylene terev described in the examples
Talate has a low isophthalic acid content of 20 mol%. That
Assuming that this copolymerized polyester with a low content of isophthalic acid
Even if you evaluate it as a damping material,
Although it has better damping performance in high temperature range than
The temperature of 80-100 ° C required as a damping material around the engine
The damping performance in the frequency range is not sufficient, and further improvement is desired.
It is rare. Japanese Unexamined Patent Publication (Kokai) No. 58-167617 discloses a vibration damping device of the present invention.
Gas barrier is one of the copolyesters that make up materials
It has excellent properties and is useful for hollow containers and film for packaging.
Only as a result, it has excellent damping performance and is used as a damping material.
There is no suggestion that it will be useful.

[Problems to be Solved by the Invention] An object of the present invention is to provide a new damping material.
Another object of the present invention is to provide a damping material having a wide temperature range, which exhibits damping performance. Still another object relates to a vibration damping material having excellent vibration damping performance in a high temperature range. Another object is to provide a vibration damping material having a high loss coefficient η showing vibration damping performance between 80 and 100 ° C. Still other objects of the present invention will be apparent from the description herein.

[Means for solving problems]

That is, according to the present invention, 80 to 100 mol% of the dicarboxylic acid component is isophthalic acid, 0 to 20 mol% is another dicarboxylic acid, and 5 to 15 mol% of the dihydroxy compound component is 1,3- Screw (2-
A vibration damping material is provided which comprises an amorphous copolyester which is hydroxyethoxy) benzene and / or 1,4-bis (2-hydroxyethoxy) benzene, and 75 to 95 mol% of ethylene glycol.

[Work]

The copolyester constituting the damping material according to the present invention,
The dicarboxylic acid component is composed of an isophthalic acid component and another dicarboxylic acid component, but 80 to 100 mol% of the dicarboxylic acid component is isophthalic acid, 0 to 20 mol% is another dicarboxylic acid, and the dihydroxy compound component is 5 to 15 mol%
1,3-bis (2-hydroxyethoxy) benzene and / or 1,4-bis (2-hydroxyethoxy) benzene, 75-95 mol% ethylene glycol.

Other dicarboxylic acid components that can be used together with isophthalic acid include aromatic dicarboxylic acids such as terephthalic acid and 2,6-naphthalenecarboxylic acid, oxalic acid, succinic acid, adipic acid, sebacic acid, undecadicarboxylic acid, etc. Are selected from aliphatic dicarboxylic acids, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, or two or more kinds thereof, and among these, terephthalic acid is most common.

As the dihydroxy compound which is another component of the copolyester, 1,4-bis (1,3-bis (2-hydroxyethoxy) benzene, 1,4-bis (hydroxyethoxy) benzene-propylene glycol, 1,4- Aliphatic glycols such as butanediol, neopentyl glycol, hexamethylene glycol,
It is also possible to use an alicyclic glycol such as cyclohexanedimethanol, an aromatic dihydroxy compound such as bisphenol, or a dihydroxy compound selected from two or more of these.

The copolymerized polyester may be modified with a small amount of a trihydroxy or higher polyhydroxy compound such as triol or tricarboxylic acid or polycarboxylic acid as long as it exhibits thermoplasticity.

Among the above-mentioned copolymerized polyesters, the balance of the dicarboxylic acid component is 5 to 15 of terephthalic acid and dihydroxy compound.
A copolymerized polyester in which mol% is 1,3-bis (2-hydroxyethoxy) benzene or 1,4-bis (2-hydroxyethoxy) benzene and 75 to 95 mol% is ethylene glycol has a vibration damping property. Peak temperature 90 ±
In addition to being in the range of 5 ° C., the loss coefficient η is large, and it is suitable as a high temperature damping material.

The copolyester of the present invention is amorphous because it has a high isophthalic acid content. The glass transition temperature (Tg) varies depending on the composition, but is preferably in the range of 50 to 70 ° C.

Amorphous in the present invention is a resin that does not cause devitrification due to crystallization when left in an atmosphere of 190 ° C. for 3 hours or more, and has no clear crystallization or crystal melting peak in DSC measurement. It is a resin. Tg is a value obtained from the transition point of latent heat at the time of temperature increase by DSC at a temperature increase rate of 10 ° C / min. The molecular weight is not particularly limited as long as it does not inhibit the film forming property, but is usually o-chlorophenol 25 ° C.
IV is 0.6 dl / g or more, preferably 0.8 to 0.9 dl / g
It is in the range of.

The damping material of the present invention can be used in the form of a composite laminate with a metal plate, or in the form of a composite composition.

A method of using the copolyester as a vibration damping material composed of a composite laminate will be described below. The composite laminate for vibration damping material is such that at least the outer layer is made of metal and at least one layer of the intermediate layer is made of the copolyester, and the metal layer forms not only the outer layer but also one layer of the intermediate layer. However, the structure of the composite laminate that can be used is exemplified by the following structures.

(I) metal / copolyester (ii) metal / copolyester / metal (iii) metal / copolyester / metal / copolyester (iv) metal / copolyester / metal / copolyester / metal Among the composite laminates having the constitution, (ii) the composite laminate having a three-layer structure is particularly preferably used. The structure of the composite laminate can be used as a plate, a cylinder, a prism, or any other shape of structure.

Examples of the metal forming the composite laminate include iron, steel, copper, aluminum, stainless steel, brass and the like. The thickness of the metal is arbitrary, but is usually in the range of 0.1 to 2 mm, preferably 0.3 to 1 mm.

As the intermediate layer constituting the composite laminate, a copolyester can be used alone, or another polymer can be blended and used, and further various inorganic fillers can be blended. It is also possible to do so. For example,
It is permissible to incorporate modified polyolefins in order to improve the adhesion to metal or to change the damping pattern. As the modified polyolefins, acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid, bicyclo [2.2.1] hept-2-ene-5,6
It is preferable to incorporate a modified olefin polymer obtained by graft-copolymerizing an unsaturated carboxylic acid derivative component unit consisting of an unsaturated carboxylic acid such as dicarboxylic acid, an acid anhydride thereof, a salt thereof or an ester thereof. As olefin copolymerization, ethylene, propylene, 1-butene, 4-
Methyl-1 pentene, 1-hexene, 1-octene, 1
A homopolymer of α-olefin such as decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene may be used, or a copolymer of two or more kinds may be used. Specific examples of the inorganic filler to be added to the copolyester include graphite, mica, titanium oxide, zinc white, clay, talc, calcium carbonate, magnesium carbonate, and carbon black.

The thickness of the copolyester layer comprising the intermediate layer is arbitrary, but is usually 0.02 to 3 mm, preferably 0.03 to 0.15 mm.

As a method for producing a composite laminated plate on which a copolymerized polyester or a composition containing the same is used as an intermediate layer of a metal plate or a plurality of metal plates, a conventionally known method can be adopted.

〔The invention's effect〕

According to the present invention, it is possible to provide a vibration damping material having excellent vibration damping performance particularly in a high temperature range of 80 to 100 ° C.
It can exhibit excellent characteristics as a high temperature damping material around the engine such as a cylinder head cover.

[Examples] Hereinafter, the contents of the present invention will be described in detail with reference to preferable examples of the present invention, but the present invention is not limited to these examples unless otherwise specified.

In the table, TA is terephthalic acid, IA is isophthalic acid, EG is ethylene glycol, 1,3BHEB is 1,3-bis (2-hydroxyethoxy) benzene, and 1,4BHEB is 1,4-bis (2-hydroxyethoxy). ) Benzene, THMP is trihydroxymethyl propylene.

Example 1 In this example, 1,3-bis (2-
An example in which (hydroxyethoxy) benzene is introduced will be shown.

From 90 mol of isophthalic acid as a dicarboxylic acid component, 10 mol of terephthalic acid, 15 mol of 1,3-bis (2-hydroxyethoxy) benzene as a dihydroxy compound component, 85 mol of ethylene glycol, and 0.3 mol of trihydroxymethylpropylene as a triol component. Naru IV = 0.8
Steel is laminated by hot pressing on both sides of a 5 dl / g copolyester film, steel / resin / steel = 0.8 / 0.1 / 0.
A composite laminate of 8 (unit mm) was obtained.

Using this composite laminate, the vibration loss coefficient η at 500 Hz was measured by the method based on vibration damping at a cantilever resonance point. The results are shown in Table 1.

In this measurement method, from the transient characteristics of the excitation force when the excitation is stopped,
Since the upper limit of η measurement value is limited to about 0.6, η = 0.2〜
It should be noted that the range of 0.6 is compressed slightly lower than the actual value. As a result, the loss coefficient η at 500Hz is 0.0056 at 25 ℃, 0.032 at 70 ℃, 0.11 and 90 at 80 ℃.
0.34 at ℃, 0.26 at 100 ℃, η peak temperature is 90 ℃
It turns out that it exists in the vicinity. Therefore, the vibration damping performance between 80 and 100 ° C is extremely excellent. The results are shown in FIG. 1 for reference.

Example 2 A mixture of 10 mol of terephthalic acid, 90 mol of isophthalic acid, 92.5 mol of ethylene glycol, 7.5 mol of 1,4-bis (2-hydroxyethoxy) benzene and 0.3 mol of trihydroxymethylpropylene, IV = 0.86 dl / g. Example 1 was repeated except that polymerized polyester was used. as a result
Loss factor at 500Hz is 0.03 at 70 ℃, 0.09 at 80 ℃, 90 ℃
It was 0.30 and 0.27 at 100 ° C.

Comparative Examples 1-2 The dicarboxylic acid component was isophthalic acid and terephthalic acid, and the dihydroxy compound component was used in the same manner as in Example 1 using a copolyester having ethylene glycol.
The results are shown in Table 1, FIG. 2 (500 Hz) and FIG. 3 (1 KHz).

Comparative Example 3 A copolymerized polyester having isophthalic acid and terephthalic acid as the dicarboxylic acid component, ethylene glycol as the dihydroxy compound component, and triol or tricarboxylic acid was used and measured in the same manner as in Example 1. The results are shown in Table 1.

[Brief description of drawings]

FIGS. 1 to 3 are diagrams showing the vibration damping performance of the product of the present invention and the target product. FIGS. 1 and 2 show a frequency of 500 Hz, and FIG. 3 shows 1 KH.
It is the measurement result at z.

Claims (6)

[Claims] 1. A dicarboxylic acid component is 80 to 100 mol% isophthalic acid, 0 to 20 mol% is another dicarboxylic acid, and 5 to 15 mol% of the dihydroxy compound component is 1,3-bis ( 2-hydroxyethoxy) benzene and / or 1,
4-bis (2-hydroxyethoxy) benzene, 7
A damping material made of an amorphous copolyester in which 5 to 95 mol% is ethylene glycol. 2. The vibration damping material according to claim 1, wherein the copolyester is modified with a trihydroxy or higher polyhydroxy compound and / or a polycarboxylic acid. 3. The vibration damping material according to claim 1 or 2, wherein the other carboxylic acid is terephthalic acid. 4. The damping material according to any one of claims 1 to 3, wherein the peak temperature of the loss coefficient η is in the range of 90 ± 5 ° C. 5. The vibration damping material according to any one of claims 1 to 4, which is a laminate of a copolyester and a metal. 6. The vibration damping material according to any one of claims 1 to 5, which is used for an engine oil pan or a cylinder head cover.