JPS6356522A - Vibration-proof material - Google Patents

Abstract

PURPOSE:To obtain a vibration-proof material, by copolymerizing isophthalic acid in a specific amount, showing excellent vibration-damping properties within a high-temperature region and suitable as high temperature vibration damping materials for engine circumference parts such as oil pan, cylinder head covers, etc. CONSTITUTION:A vibration-proof material is obtained by reacting (A) 40-100mol% isophthalic acid and (B) 0-60mol% other dicarboxylic acid component (e.g. terephthalic acid, etc.) with a dihydroxy compound such as ethylene glycol, etc., to provide a copolyester having preferably 50-70 deg.C glass transition temperature and >=0.6dl/g inherent viscosity and laminating the resultant copolyester to a metal sheet to form a composite laminate.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a vibration damping material, and more specifically, in a high temperature region, especially in a range of 80 to
The present invention relates to a damping material that exhibits excellent damping performance at around 100°C and is useful as a high-temperature damping material for engine peripheral parts such as an oil pan.

[Conventional technology]

Conventionally, in order to suppress or prevent noise and vibration generated from various mechanical devices, electrical devices, structures, etc., viscoelastic resins and resin compositions have been used as damping materials between substrates such as metal plates. A vibration damping composite laminate has been proposed or put into practical use, in which vibration damping performance is achieved by interposing the vibration damping material in layers and utilizing internal friction caused by shear deformation of the damping material. An example of such a damping material composition is disclosed in JP-A-54
No. 43251 or Japanese Patent Application Laid-Open No. 54-43252 describes a composition containing polyisobutylene as a main component and blending this with a diene hydrocarbon polymer or a cyclic olefin polymer and an inorganic filler. There is. Japanese Patent Application Publication No. 5
No. 7-34949 describes a damping material made of ethylene/vinyl acetate copolymer.

JP-A-61-89842 describes a damping material made of polyester or polyester and polyolefin having specific properties.

Also, although there is no mention of it as a damping material, JP-A-55-12
Publication No. 3458 describes a composite laminate of non-grade polyethylene terephthalate and metal using terephthalic acid and a small amount of isophthalic acid as dicarboxylic acid components.

Further, the same kind of polyester constituting the vibration damping material of the present invention is described in Japanese Patent Application Laid-open No. 167617/1983.

[Problems with conventional technology]

Among the above-mentioned conventional techniques, Japanese Patent Application Laid-Open No. 54-43251, Japanese Patent Application Laid-Open No. 54-43252, and Japanese Patent Application Laid-Open No. 57-3
The material disclosed in Japanese Patent No. 4949 does not have sufficient vibration damping properties, and has a particularly poor vibration allocation performance at high temperatures, so there is a problem in that it cannot be used as a high temperature vibration damping material for the periphery of an engine, for example.

The material disclosed in JP-A No. 61-89842 is a damping material made of amorphous polyester, which has relatively high elongation (and softness), and also mentions terephthalic acid and Eastman Kodak's KODAR@P is an example of a copolyester of isophthalic acid.
CTA resin A-150 has an isophthalic acid content of 25 mol%
Moreover, the influence of temperature on the loss coefficient η is very large, and the temperature range in which a high η value is exhibited is extremely narrow. As mentioned above, JP-A-55-123458 has no suggestion whatsoever about its use as a vibration damping material, and the amorphous polyethylene terephthalate described in the examples has an isophthalic acid content of 20 mol%. and few. Even if this copolymerized polyester with a low isophthalic acid content were evaluated as a vibration damping material, it would be true that it has superior vibration distribution performance in high temperature regions compared to conventional damping materials. It cannot be said that the distribution performance in the temperature range of 80 to 100°C required for the material is sufficient, and further improvement is desired.

JP-A-58-167617 only discloses that a type of copolyester constituting the vibration damping material of the present invention has excellent gas barrier properties and is useful for hollow containers and packaging films. There is no suggestion that it has excellent vibration performance and is useful as a damping material.

[Problem that the invention seeks to solve]

An object of the present invention is to provide a novel damping material.

Another object of the present invention is to provide a damping material that exhibits damping performance over a wide temperature range. Still another object of the present invention relates to a damping material that has excellent vibration allocation performance in high-temperature regions. Another objective is to increase the value of the loss coefficient η, which indicates vibration damping performance, from 80 to 100°C.
The objective is to provide a damping material that exhibits a high value between. Still other objects of the present invention will become apparent from the description herein.

[Means for solving problems]

That is, the present invention is a damping material made of a copolymerized polyester in which 40 to 100 mol% of the dicarboxylic acid component is isophthalic acid and 0 to 60 mol% is another dicarboxylic acid.

[For production]

In the copolyester constituting the damping material of the present invention, the dicarboxylic acid component is composed of isophthalic acid and other dicarboxylic acids, and the isophthalic acid content is 40 to 100 mol%, particularly 50 to 100 mol%.
100 mol%, more preferably 80 to 100 mol%, and other dicarboxylic acids 0 to 60 mol%, especially 0 to 50 mol%.
The copolymerized polyester preferably has a mole % of 0 to 20 mole %. When the isophthalic acid content is less than 40 mol%, the temperature at 80 to 100°C is an important factor for high-temperature vibration damping materials.
The vibration damping performance is poor.

Other dicarboxylic acid components that can be used with isophthalic acid include terephthalic acid, aromatic dicarboxylic acids such as 2,6-naphthalene dicarboxylic acid, oxalic acid, succinic acid,
Aliphatic dicarboxylic acids such as adipic acid, sebacic acid, undecadicarboxylic acid, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, or two or more of these, and among these, terephthalic acid is particularly preferred. is the most common.

Dihydroxy compounds, which are other components of the copolymerized polyester, include ethylene glycol, propylene glycol, 1
, 4-butanediol, neopentyl glycol, aliphatic glycols such as hexamethylene glycol, alicyclic glycols such as cyclohexane dimetatool, bisphenol, 1,3-bis(2-hydroxyethoxy)benzene, 1,4-bis An aromatic dihydroxy compound such as (hydroxyethoxy)benzene, or a dihydroxy compound selected from two or more of these compounds can be used. Further, the copolymerized polyester may be modified with a small amount of a trivalent or higher polyhydroxy compound such as triol or tricarboxylic acid, or polycarboxylic acid, as long as it exhibits thermoplasticity.

Among the copolymerized polyesters, the remainder of the dicarboxylic acid component is terephthalic acid and dihydroxy compound in an amount of 5 to 90 mol%, particularly 10 to 15 mol% of 1.3
-bis(2-hydroxyethoxy)benzene or 1
．． A copolymerized polyester consisting of 4-bis(2-hydroxyethoxy)benzene and 10 to 95 mol%, especially 75 to 90 mol% of ethylene glycol has a peak temperature of vibration damping performance in the range of 90±5°C. In addition, the value of the loss coefficient η is large, making it suitable as a vibration damping material for high temperatures.

The copolymerized polyester of the present invention has a high content of isophthalic acid and is therefore inferior in quality. Also, glass transition temperature (Tg)
varies depending on the composition, but is preferably in the range of 50 to 70°C.

In the present invention, non-quality resin refers to a resin that does not devitrify due to crystallization when left in an atmosphere at 190°C for 3 hours or more, and does not have a clear crystallization or crystal melting peak when measured by DSC. It is resin.

Tg is a value determined by DSC from the transition point of latent heat during temperature increase at a temperature increase rate of 10° C./In1n. The molecular weight is not particularly limited as long as it does not inhibit film forming properties, but usually the I and V of 0-chlorophenol at 25°C are 0.6 dI/g or more, preferably 0.8 to 0.9 d! /
g range.

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.

Next, a method of using copolymerized polyester as a vibration damping material made of a composite laminate will be described. The composite laminate for vibration damping material has at least an outer layer made of metal and at least one intermediate layer made of the copolymerized polyester, and the metal layer forms not only the outer layer but also one of the intermediate layers. Examples of acceptable configurations of the composite laminate include the following configurations.

(i) Metal/Copolyester (ii) Metal/Copolyester/Metal (iii)
Metal/copolymerized polyester/metal/copolymerized polyester (iv) Metal/copolymerized polyester/metal/copolymerized polyester/metal Among these composite laminates, the three-layered composite laminate in (ii) is particularly effective. Preferably used. The structure of the composite laminate can be used as a plate-shaped body, a cylindrical body, a prismatic body, or any other arbitrary structural shape.

Examples of the metal constituting the composite laminate include iron, steel, copper, aluminum, stainless steel, and brass. The thickness of the metal is arbitrary, but usually 0.1 to 2 mm, preferably 0.3 to III1
The range is 1.

As the intermediate layer constituting the composite laminate, copolyester can be used alone or in combination with other polymers, and various inorganic fillers can be added. It is also possible to do so. for example,
Modified polyolefins may be blended to improve adhesion to metals or to change the vibration damping pattern. Examples of modified polyolefins include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid, and bicyclo(2,2,1)hept-2-ene-5,6-dicarboxylic acid; It is preferable to blend a modified olefin polymer obtained by graft copolymerizing an unsaturated carboxylic acid derivative component unit consisting of an acid anhydride, a salt thereof, or an ester thereof. Examples of olefin copolymerization include ethylene, propylene, 1-butene, 4-methyl-1pentene, tohexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-
It may be a homopolymer of α-olefins such as hexadecene or 1-octadecene, or it may be a copolymer of two or more types. Specifically, inorganic fillers that are added to copolyester as necessary include:
Examples include graphite, mica, titanium oxide, zinc white, clay, talc, calcium carbonate, magnesium carbonate, and carbon black.

The thickness of the copolymerized polyester layer consisting of the intermediate layer is arbitrary, but is usually 0.02 to 3 mm, preferably 0.0 mm.
It is in the range of 3 to 0.15 mm.

Conventionally known methods can be used to create a composite laminate in which a copolymerized polyester or a composition containing the copolyester is formed on a metal plate or as an intermediate layer between a plurality of metal plates.

〔Effect of the invention〕

According to the present invention, it is possible to provide a damping material that has excellent vibration distribution performance in a high temperature range, particularly between 80 and 100°C, and therefore has excellent properties as a high temperature damping material for engine peripheral areas such as oil pans and cylinder rad covers. able to demonstrate.

〔Example〕

The content of the present invention will be explained in detail below using preferred examples of the present invention, but unless otherwise specified, the present invention is not limited to these examples in any way.

In the table, TA is terephthalic acid, IA is isophthalic acid, T
MA is 1,2,3-1-licarboxylbenzene, EG
is ethylene glycol, and THMP is trihydroxymethylpenkune.

Example 1 and Comparative Examples 1 to 2 Steel was laminated by hot pressing on both sides of a copolyester film consisting of terephthalic acid, isophthalic acid, and ethylene glycol in the composition ratios shown in Table 1, and steel/resin/steel = 0. A composite laminate of .810.110.8 (unit: mm) was obtained.

Using this composite laminate, the vibration loss coefficient η at various frequencies was measured by a method using vibration damping at the resonance point of a cantilever beam. The results are shown in Table 1, Figures 1 and 2.

In addition, in this measurement method, from the excitation force transient characteristics when excitation is stopped,
Since the upper limit of η measurement value is limited to about 0.6, η=0
．． It should be noted that the range of 2 to 0.6 is compressed slightly lower than the actual value.

As can be seen from these results, the copolyester with a high isophthalic acid content as in the present invention has a
The loss coefficient is large between °C (therefore, it can be seen that the vibration damping performance is excellent).

Examples 2 to 4 and Comparative Example 3 Results measured in the same manner as in Example 1 using a copolymerized polyester in which the dicarboxylic acid component is isophthalic acid and terephthalic acid, the dihydroxy compound component is ethylene glycol, and a triol or tricarboxylic acid. are shown in Table 2.

Example 5 In this example, 1,3-bis(2
-Hydroxyethoxy)benzene is introduced.

90 mol of isophthalic acid, 10 mol of terephthalic acid as dicarboxylic acid component, 1.3 mol as dihydroxy compound component
- 15 moles of bis(2-hydroxyethoxy)benzene,
1,V, -0,85d!, consisting of 85 moles of ethylene glycol and 0.3 moles of trihydroxymethylpenkune as a triol component! The same procedure as in Example 1 was carried out except that a copolymerized polyester of /g was used. the result,
One-member lapse coefficient η at 500Hz is 0.0056 at 25°C
．． It is 0.032.80°C at 70°C, 0.11, 0.34 at 90°C, and 0.26 at 100°C, and it can be seen that the heat temperature of η exists around 90°C. Therefore 80-10
Very good vibration damping performance at 0°C.

The results are shown in Figure 3 for reference.

Example 6 I consisting of 10 moles of terephthalic acid, 90 moles of isophthalic acid, 92.5 moles of ethylene glycol, 7.5 moles of 1,4-bis(2-hydroxyethoxy)henzene, and 0.3 moles of trihydroxymethyl penkune. ,V,-0,86
d! The same procedure as in Example 1 was carried out except that a copolymerized polyester of /g was used. As a result, the loss coefficient at 500)1z is 0.03.80°C at 70°C and 0.09.90°C.
．． It was 0.27 at 30 and 100°C.

[Brief explanation of the drawing]

1 to 3 are diagrams showing the allocation performance of the product of the present invention and the target product. FIGS. 1 and 3 show the measurement results at a frequency of 500H2, and FIG. 2 shows the measurement results at a frequency of IKH2.

Claims (8)

[Claims] (1) A damping material made of a copolymerized polyester in which 40 to 100 mol% of the dicarboxylic acid component is isophthalic acid and 0 to 60 mol% is another dicarboxylic acid. (2) The damping material according to claim 1, wherein 50 to 100 mol% of the dicarboxylic acid component is isophthalic acid and 0 to 50 mol% is another dicarboxylic acid. (3) The damping material according to claim 1 or 2, wherein the copolymerized polyester is modified with a polyhydroxy compound/or polycarboxylic acid having a valence of 3 or more. (4) The damping material according to any one of claims 1 to 3, wherein the other dicarboxylic acid is terephthalic acid. (5) 5 to 90 mol% of the dihydroxy compound component is 1
, 3-bis(2-hydroxyethoxy)benzene and/or 1,4-bis(2-hydroxyethoxy)benzene, 10 to 95 mol% of which is ethylene glycol. Vibration damping material described in Crab. (6) The damping material according to claim 5, wherein the peak temperature of the loss coefficient η is in the range of 90±5°C. (7) The damping material according to any one of claims 1 to 6, wherein the copolyester is laminated with a metal. (8) The damping material according to any one of claims 1 to 7, which is used for an engine oil pan or a cylinder head cover.