JPS6038149A - Vibration-damping laminate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composite vibration damping laminate, and more particularly to a composite vibration damping laminate consisting of a polymeric material layer and a metal layer, which have damping performance against metals.

In recent years, noise from industrial machines and structures, as well as automobiles, which are essential to social life, has come into focus as a social problem, and as a result, various noise prevention measures have been required.

As a conventional specific noise prevention measure, many methods have been taken in which materials having different functions such as sound insulation, sound absorption, vibration isolation, and vibration damping materials are used in combination.

Meanwhile, in the automobile industry, in addition to noise prevention measures, weight reduction is being promoted in order to cope with fuel efficiency regulations and energy supply issues that are becoming increasingly strict due to the trends of the times. Examples include thinning steel plates for panels, or introducing aluminum alloys, plastic materials, etc. as substitutes for steel materials. On the other hand, as automobiles become lighter, the vibrations of the automobile itself tend to become more intense, leading to an increase in noise.

Therefore, how to reduce vibration will be an important issue in the future.

Recently, as part of the vibration prevention measures, methods using vibration-proofing alloys, methods of laminating damping materials to metals, or composite vibration-damping materials in which polymeric substances are sandwiched between metals have been used. Methods have been developed and are beginning to be adopted in a wide range of fields.

In general, loss coefficient (η), logarithmic damping ratio (c), resonance sharpness (correspondence), etc. are used as measures of the vibration damping effect of damping materials such as damping steel plates, and these are interrelated. is a certain physical property value. Among these physical property values, the loss coefficient (η
) is the most commonly used material, and conventionally it was said that if l is 0003 or more, the damping effect is great, but with the recent tightening of noise regulations, it is expected that more vibration damping materials with η will be developed. .

The purpose of the present invention is to further improve the loss coefficient (η) in accordance with the above-mentioned trends of the times.
The purpose of the present invention is to provide an allocating material that is large in size and has excellent workability.

The gist of the present invention is as follows.

That is, in a composite vibration damping laminate comprising a polymer material layer and a metal layer that have damping performance against metal,
The polymeric substance includes (A) polyvinyl acetal resin and (
B) Polyalkylene isophthalate/terephthalate and in some cases (C) Town l! This is a composite vibration damping laminate characterized in that it is a substance containing a component consisting of an agent.

Composite damping materials generally have a polymer substance sandwiched between metals such as steel plates, so η changes depending on the operating temperature, and η has the property of reaching a peak at a certain temperature. . Therefore, it is necessary to select a polymer material that is compatible with the intended use temperature, but the research conducted by the present inventors has shown that it is possible to change the temperature at which the loss coefficient (η) value is maximized by using plasticizers and additives. This was confirmed. Of course, as a vibration damping material, the smaller the temperature dependence and the higher η, the better.

In general, it is said that the higher the loss tangent (tan δ) of the polymeric substance used to improve the vibration damping properties of a laminated body such as a double-sided damped laminated steel plate, the better.

Another aspect of the composite vibration damping laminate is a non-constrained vibration damping laminate. This is an innovative free layer made by laminating polymer '$IJ'A with excellent distribution performance to metal such as mountain plates. In general, it is said that a polymer material having a high complex modulus of elasticity (E') is good. Recently, constrained vibration damping laminates have been attracting attention because they contain less resin and have excellent vibration distribution properties.

The present invention will be explained in detail below.

The inventors of the present invention have conducted intensive studies on polymeric materials with high vibration damping properties in laminates with metals.
It has been found that the polyvinyl acetal resin shown in No. 7 is effective. Although the resin according to the invention of the application has excellent vibration damping properties, the temperature dependence of the loss coefficient η is somewhat difficult, and the temperature range in which it exhibits effective damping properties is narrow.

The inventors of the present invention have made extensive studies to improve this drawback, and as a result have arrived at the present invention. That is, the gist of the present invention is that by adding (B) polyalkylene isophthalate/terephthalate to (A) polyvinyl acetal resin, η decreases less and η has less dependence on temperature, that is, has a broad peak. We have discovered a method that is industrially very valuable and have arrived at the present invention. It is also possible to arbitrarily control the peak of η by controlling i of the polyalkylene inphthalate/terephthalate copolymer resin. It is also possible to add (C) a plasticizer for the purpose of lowering the peak temperature (temperature exhibiting the maximum loss coefficient). In addition, polyvinyl acetal resin easily crosslinks when heated, making it difficult to handle in the molten state, but polyalkylene isophthalate resin
It is unexpected that adding a terephthalate copolymer alleviates crosslinking properties and facilitates industrial handling, which is highly beneficial.

Polyvinyl acetal resin, component (4) of the polymer used in the present invention, is produced from vinyl acetate, aldehyde, etc. Generally, vinyl acetate monomer is polymerized to form polyvinyl acetate resin 'fcfA, and then By the reaction of polyvinyl alcohol obtained by saponification with aldehyde, s
will be built.

That is, the polyvinyl acetal resin component is a copolymer resin having a vinyl acetal blue, a vinyl alcohol group, and a vinyl acetate group, and the reaction product of this resin with formaldehyde is called formal dehyde, and the reaction with butyraldehyde. The product is called butyral resin.

The average degree of polymerization of the polyvinyl acetal resin used in the present invention is preferably in the range of 300-j, θθθ, and the higher the degree of polymerization, the more preferable it is. Also, the degree of acetalization! ; OA-g! r mo is preferably about 1%.

Examples of the polyvinyl acetal resin include polyvinyl methyl, polyvinyl formal, polyhinyl acetoacetal, polyvinyl globyl acetal, etc.
Among them, polyvinyl butyral resin or polyvinyl formal resin is preferably used. Furthermore, poly and nyl acetal resins containing carboxyl groups are also preferably used. It is preferable that the carboxyl group is contained in the polyvinyl acetal resin in an amount of about 0.7 to 5 mol, preferably about 0.2 to 3 mol.

As polyvinyl acetal resin containing a carboxyl group, for example, a method of producing polyvinyl acetal resin by a conventional method using a copolymer of vinyl acetate and an unsaturated carboxylic acid, or a method of acetalizing polyvinyl alcohol. It is obtained by reacting with an aldehyde containing a carboxyl group.

The polyalkylene isophthalate/terephthalate copolymer, which is component (B) of the polymer targeted by the present invention, can be produced by melt polymerization using antimony trioxide as a catalyst (for example, dimethyl terephthalate, dimethyl heptatalate, and glycol components). Copolymers of various compositions can be produced. The content of isophthalic acid component is relative to the total acid component! - The appropriate person is in charge of the Omol. & The limiting viscosity is not particularly limited, but may be within the range of o, s - o, 'y dt7y. Glycol components include ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, propane-/, 3-
Diol, butane-7, Hiro-diol, polytetramethylene glycol, cyclohydroxymethylcyclohexane neopentyl glycol, etc. are used. Particularly preferred are those containing ethylene glycol as a living body, and it goes without saying that ethylene glycol and other glycol components such as neopentyl glycol may be combined.

The mixing composition ratio of polyvinyl acetal resin and polyalkylene may be in the range of 10% by weight to 90% by weight to 10% by weight. For example, the composition ratio is 7 for polyvinyl acetal resin.
If it is less than 0% by weight, it will be dominated by the distribution properties of the polyalkylene isophthalate and terephthalate resins, and conversely, if it exceeds θ, it will be dominated by the polyvinyl acecool resin, and there will be no effect of mixing the two. Furthermore, in order to adjust the temperature range in which the maximum value of η is obtained, it is effective to add a plasticizer as the component (C). It is preferable that the amount added does not exceed 4 tO parts by weight per 100 parts of the total of components (A) and (B). If it exceeds lIo parts by weight, it is not preferable because it causes a decrease in adhesive strength to metal surfaces and a decrease in the absolute value of η.

Examples of plasticizers that can be added include phthalic acid esters such as dibutyl phthalate, dioctyl phthalate, and butylbenzyl heptatalate, phosphorus esters such as tricresyl phosnate, dibutyl sebacate, zicoethylhexyl adipate, and dibutyl succinate. Glycol derivatives of fatty acid S, vegetable oils such as soybean oil, linseed oil, and castor oil, and epoxidized products thereof are commonly used, and in the present invention, any one may be selected from these. . The role of the plasticizer is as described above, but in general, as the amount of plasticizer added increases, the maximum value of the loss coefficient (ri) shifts to a lower temperature range.

Inorganic fillers can also be added for the purpose of improving the elastic modulus, adhesiveness, etc. of the polymer composition. Examples include scaly graphite, mica, conductive carbon black, carbon graphite, talc, and magnesium carbonate. The amount added is about io to 10 OTL parts, preferably about 10 to 50 parts by weight, per 100 Mtix parts in total of components (A) and (B).

Next, metals used in the laminate according to the present invention will be explained. As the metal plate used in the present invention, a steel plate is most suitable due to its adhesion to the molecular substance used as an intervening body, strength, price, etc., but other metal plates such as copper plate, aluminum plate, etc. Available for use.

Steel plates include mild steel plates, high-tensile steel plates, stainless steel plates,
Surface-treated steel sheets such as galvanized steel sheets, or steel sheets that have been surface-treated by methods commonly used for preliminary treatment of metal surfaces, such as phosphate or chromate treatment, can also be used depending on the purpose of use. The surface of these steel plates should be clean in order to obtain the best adhesion with the viscoelastic polymeric material, and for this purpose sandblasting or the like may be necessary in some cases.

These steel plates may be used as flat plates, but they may also be subjected to bending or drawing depending on the shape of the desired laminate. In addition, the steel plates used as vibration-damping laminates are heated during the manufacturing process, so if a steel plate that ages easily is used, a surface distortion pattern called stretcher strain will occur during processing, which will impair the appearance. , if the appearance after processing is important, the aging index (A, 1.) is 8, t.
A non-aging steel plate of Kff/- or less should be used.

In order to manufacture such a distributed laminate, for example, a so-called pressing method is used, in which two metal plates are fed into a roll, and a polymer material extruded in a sheet form in a molten state from an extruder is fed between the metal plates. In the extrusion lamination method, a polymer material is dissolved in a solvent, applied to a metal plate, heated to evaporate the solvent, and melt the polymer material. Any method can be used, such as a coating lamination method in which the plate f or the pressing surface is layered.

Note that various shapes, thicknesses, etc. of metal plates are used depending on the intended product, but in general, for example, in the case of a JNi structure in which a polymer substance 14 is interposed between one metal plate, metal It is sufficient that the plate has a thickness of θ, θ/lan or more, and the molecular material layer has a thickness of 7740 or more of the metal plate.

Although the thickness of the metal plate is usually the same on both sides, it may be different depending on the application, and it is also possible to form a laminate of three or more layers depending on the application.

The temperature dependence of the loss coefficient η of the vibration damping laminate can be determined by placing the test material in a constant temperature chamber, setting it to each cypress temperature, changing the frequency, and calculating the loss coefficient from the sharpness of the resonance point of the mechanical impedance. I got it good.

The vibration damping properties were determined in the seventh temperature range where the absolute value of η was 0.1 or more, and in the second temperature range where the absolute value of η was 0.3 or more.

Example 1 A normal cold-rolled steel plate with a size of 0.6 wires x 25θ nodes x 5θ was degreased with trichlorene, and this was used as a metal base material for a laminate according to the present invention.

The aging index of the steel plate was θKgf/mm.

Next, the degree of polymerization is iozθ, the degree of butylation is 1%, polybutyral resin S5 weight M%, dioctyl 7 tallate/θ weight:
l! :%, isophthalic content 1 comol, intrinsic viscosity 03
3snx% of polyethylene phthalate/terephthalate copolymer (g) was mixed well and melt-kneaded at 30C in a single-screw extruder with a diameter of θ and φ to form pellets. Using the pellets, JOθ■
A sheet with a thickness of 10μ was obtained at trrm. The sheet was sandwiched between the two steel plates mentioned above and heated to λ
The material was preheated and degassed for 3 minutes at the JOC temperature, and then crimped under heat and pressure for an additional 3 minutes to obtain a composite vibration damping material with a plate thickness of J m.

The temperature dependence of the loss coefficient η of the composite damping laminate thus obtained is shown in Figure 1(a).

Example - Using the same raw materials as in Example -/, 6 g weight % of polyvinyl butyl, dioctyl 7-thalerate/co-dioctyl, polyethylene isophthalate/terephthalate copolymer, 20
After pelletizing using the same method as Example-/ using weight i%,
A waste-type damping laminate was obtained. The temperature dependence of η is shown in Figure 7 (
(b).

Comparative Example-/Polyvinyl butyral S3, which is the same raw material as Example-1
A composite vibration damping laminate was obtained after pelletizing in the same manner as in Example 1 using a heavy-duty lid and dioctyl phthalate/j weight t%. The temperature dependence of η is shown in (c) of Figure l.

Comparative Example - A composite damping laminate was obtained by pelletizing the polyethylene phthalate/terephthalate copolymer, which is the same raw material as in Example 7, in the same manner as in Example 1. The temperature dependence of η is shown in Figure 1).

The temperature range of 40.7 or higher and the temperature range of 0.3 or higher in Figure 2 are summarized in Table λ.

Table-C Example 3 In Example 1, polyvinyl formal with a degree of polymerization of 3θ and a degree of formalization of 6% was used instead of polyvinyl butyral, and butylbenzyl V-t was used instead of the plasticizer dioctyl slate. A composite vibration damping multilayer body was obtained in the same manner as in Example 1 except that it was used. The maximum value of loss coefficient (η
+nax) is 0. 'I9, and the temperature at this time was 9 degrees Celsius.

[Brief explanation of the drawing]

Figure 7 shows the composite damping fft layer body loss coefficient η by Yoshihito Ugeta Kawasaki Steel Corporation Mitsubishi Chemical Industries, Ltd. Representative Patent attorney For long diameter - (1 other person) Figure 1 Asahi □ Temperature (0C ) Continued from page 1 @ Inventor Masatoshi Suzuki @ Inventor Yoshihiro Matsumoto [Partner] Inventor Masatoshi Shinozaki 0 Inventor Minoru Nishi 1)

Claims (1)

[Scope of Claims] (1) A composite vibration damping laminate made of carbon having a polymer material layer having vibration damping performance for metal and a metal layer, wherein the polymer material is (4) polyvinyl acecool. Resin lθ ~ 0% by weight (B) Polyalkylene inphthalate/terephthalate copolymer resin 90 ~ IQ weight - optionally further (C) Based on the total of 100 parts by weight of components (A) and 0) A distributed laminate characterized in that it contains less than 0 parts by weight of a plasticizer. (2) Polyvinyl acetal 4t (Jj is polyvinylph. The laminate according to claim 1, which is a tyral resin or a polyvinyl formal resin. (3) The polyalkylene isophthalate Φ terephthalate copolymer resin has an intrinsic viscosity 0.3 to 0.9 dt/f and an inphthalic acid component content of 3 to 4 tomol. (4) The laminate according to claim 1 or 2, wherein the metal is a steel plate. Range 1st to 3rd
The laminate according to any of paragraphs.