JPS6056937B2 - Vibration damping material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an allocation material, and more particularly to an allocation material in which a fibrous material mainly composed of lead fibers and a polymeric substance are integrated.

motor engine, automobile engine, compressor,
BACKGROUND ART It is desired to prevent vibrations or noise from mechanical equipment such as pumps that generate vibrations or noise, and attempts have been made to attach vibration-allocating materials directly to them or to the environment surrounding them. Various materials have been proposed as allocation materials for use in these materials. One of them is a distribution material obtained by integrating a specific fibrous material into a specific polymeric material by means of mixing the two into one. Although this distribution material also exhibits a corresponding distribution effect, it is not possible to simply combine a specific polymeric substance and a specific fibrous material without making any special efforts. It was believed that improvements could not be expected beyond a certain limit. In particular, when the resonator material is directly attached to the above-mentioned mechanical equipment that generates vibration or noise, the temperature rises to 80 to 120°C. Not only will it not be possible to use it as a material, but the material itself will become soft and its shape retention will deteriorate.

In addition, conventional materials have been known that integrate fibrous materials such as inorganic fibers and polymeric materials, but
It was difficult to exhibit high allocation performance up to a high temperature of 20°C. Therefore, the present inventors dared to dramatically improve the distribution properties of the distribution material made of the above-mentioned polymeric substance and fibrous material, and in particular to improve the distribution properties and the morphological stability of the distribution material itself over a wide temperature range. As a result of intensive research into this problem, we discovered that the above problem can be solved by processing a fibrous material into a specific state and using a material obtained by integrating this with a polymeric material as an allocation material. I reached it.

Accordingly, an object of the present invention is to improve the distribution characteristics and morphological stability of a distribution material formed by integrating a fibrous material and a polymeric substance over a wide temperature range.

The purpose of this is to integrate a fibrous material mainly composed of lead fibers whose intertwined points are joined with a tree whose dynamic elastic modulus at 120°C is at least 5×IC)' to 9/CF1f and a polymeric material. This can be achieved by making the allocation material made of

That is, the main point of the present invention is that the fibrous material present in the polymer material maintains a high elastic modulus even at temperatures of 80 to 120 DEG C. and exists as a continuous layer.

For this, the dynamic elastic modulus of the fibrous material at 120°C is at least 5K9/C! It is important to join the intertwined points with resin i. Therefore, according to the present invention, since the fibrous material exists as a continuous layer while maintaining a high elastic modulus, the dynamic elastic modulus E of the damping material becomes large. on the other hand,
In addition to the internal loss of the matrix resin (η = 1/Q),
The internal friction, ie, η, increases due to the interfacial effect between the fibrous material and the matrix resin. Moreover, these range from room temperature to 80°C.
The vibration damping material of the present invention maintains high E/Q, that is, high vibration damping performance, from room temperature to high temperatures of 80-120°C. Specifically, the manufacturing method of the damping material of the present invention, the structure, characteristics, uses, etc. of the obtained damping material will be sequentially explained.

Prepare the fibrous material.

The fibrous material used in the present invention is long fibers or short fibers of a substance having a very high softening point and a high elastic modulus.
As the fibrous material corresponding to this, it is most desirable to use lead fiber from the viewpoint of weight addition effect. Next, the intertwined points of the fibrous material are joined. There is a so-called eye seal. The resin used for sealing must have a dynamic elastic modulus of at least 5K9/Ai at 120°C in order to effectively develop the high elastic modulus of the fibrous material. For example, heat-resistant resins such as aromatic polyamide, polyimide, polyamideimide, polycarbonate, . Thermoplastic resins such as polymethyl methacrylate, poly α-methylstyrene, and polyethylene-2,6-naphthalate, thermosetting resins such as phenol, epoxy, unsaturated polyester, and melamine resins are used as sealing resins. I'll come. On the other hand, the polymer material used to be integrated with the fibrous material includes resins made of organic or inorganic polymers that have a high vibration damping rate in the temperature range of 80 to 120 DEG C. For example, organic polymers include polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polymethyl methacrylate,
Thermoplastic resins such as polybutylene terephthalate and polycapramide, thermosetting resins such as phenol, epoxy, unsaturated polyester, melamine, area, and alkyd resins, butyl rubber, chloroprene rubber, ethylene-
Rubbers such as propylene rubber and nitrile rubber, tars such as asphalt, cellulose, cellulose acetate, and proteins are used.

Silicone, silicon, boron, phosphorus, sulfur, aluminum-based polymers, etc. can also be used as inorganic polymers.

These polymeric materials include single polymers, copolymer polymers,
It may be a blended polymer, or metal powder, talc,
It may also contain various granular or scaly fillers such as clay, carbonate, calcium, and mica.

of the above raw materials for obtaining the vibration damping material of the present invention. The integration is
Accomplished by any method. For example, an integrated sheet of a sealed fibrous material and a polymer material is heat-sealed to the vibrating body, or it is pasted with adhesive. A method of mounting using the adsorption power of a magnet, a method of attaching a semi-hardened sheet made of an integrated sealed fibrous material and a polymer material to the vibrating body, gluing and curing it, and a method of attaching it to the vibrating body. A method is adopted in which the fibrous materials sealed are laminated, a polymeric material is applied, and then the material is solidified or hardened. Furthermore, a mixture of a fibrous material, a sealing resin, and a polymeric material can be applied or sprayed onto the vibrating body, or used in the form of a sheet. The vibration damping material according to the present invention thus obtained exhibits high vibration damping effects and morphological stability over a wide temperature range.

This seems to be based on the following phenomenon. That is, as a result of the intertwined points of the fibrous material being joined and the fibrous material strength being restrained, the movement of the fibers themselves constituting the fibrous material is completely restricted, and the rigidity as a whole is increased. Therefore, assuming one form of the damping material of the present invention in which it is surrounded by, for example, a polymeric substance, the damping material itself becomes rigid as a whole due to the stiffening of the fibrous material. Furthermore, even if the damping material itself is exposed to a certain degree of high temperature, the viscoelastic properties of the polymer chains themselves that exist between or attempt to move between the constituent fibers of the fibrous material change. These changes manifest themselves as, for example, changes in the internal loss coefficient η and elastic modulus E of the damping material itself. In the vibration damping material of the present invention, this change in the properties is manifested as an improvement in the damping properties, and the combination of fibrous material and polymeric material, which has conventionally been used without any sealing, is improved. This means that the vibration damping properties are dramatically improved compared to chemical compounds. Therefore, the vibration damping material of the present invention exhibits excellent vibration damping properties and morphological stability. The vibration damping material according to the present invention is widely used in addition to the above-mentioned machinery as a vibration damping material for buildings such as residences, offices, and factories, and as a vibration damping material for precision machinery.

Next, the effects of the present invention will be explained using examples. Example 1
and Comparative Example 11 Dynamic elastic modulus at 20°C is 4.5 x 101k
Polyethylene sheets are layered on both sides of a lead fiber nonwoven fabric sealed with 9/d phenolic resin, and melt-molded in a hot press at 150°C to a thickness of 1W! n sheets were obtained.

The content of lead fiber is 71.4% by weight, and the specific gravity of the sheet is 3.
It was 5. The vibration damping performance (E/Q) of this sheet (Example 1) and a sheet molded using lead fibers without sealing (Comparative Example 1) are shown in the attached table. In addition, the value of resonance sharpness Q in the table refers to a value obtained by measuring the resonance curve (relationship curve between frequency f and amplitude ζ) of the damping material using the following formula (the same applies to the following examples).

The resonance sharpness Q is the reciprocal of the internal loss coefficient η, where F. is the frequency when the vibration amplitude is the peak value (ζp) on the resonance curve, and Δf is the frequency when the vibration and amplitude are at ζP/2 of the resonance curve, respectively. Example 2 and Comparative Example 2 A laminate of a lead fiber non-woven fabric sealed with an epoxy resin having a dynamic elastic modulus of 101k9/C7lf at 120°C and a glass mat (MC45OA manufactured by Nittobo) was prepared using an unsaturated polyester resin (Mitsui Kosatsu). After being immersed in a resin solution containing part of the manufacturing star (M2lOl) and BPOl, it was cured with a hot press at 120°C to obtain a molded plate.

This molded plate (Example 2) and a molded plate made only of unsaturated polyester resin without using fibrous materials as a comparative example (Comparative Example 2)
) are shown in the same attached table as the results of Example 1. Molded plates without fibrous materials were significantly deformed by heating and had poor shape retention. Comparative Example 3 A sheet was produced in the same manner as in Example 1, except that a lead fiber nonwoven fabric sealed with polypropylene having a dynamic elastic modulus of 1 CP kg/Clt at 120° C. was used.

The results of measuring the damping performance of this sheet are shown in the same separate table as in Example 1. When comparing the E/Q value representing vibration damping characteristics with Example 1 and Comparative Example 1, which differ only in sealing conditions, (a) At 20°C, the value of Comparative Example 1 is 89. 6%, and Comparative Example 3 was 92.3%,
(b) At 80°C, the above rates are 78.3% and 78.3%, respectively.
80.8%, and (c) At 120°C, similarly,
The percentages are 61.2% and 63.1%, respectively.

As described above, the results of this example in which polypropylene with a value lower than the dynamic elastic modulus defined in the present invention was used as a sealant were almost the same as those of Comparative Example 1 in which no sealant was used, and moreover, the results of Example 1 It turns out that it is far inferior.

Further, in Example 1, the E/Q value increases with temperature, but in Comparative Examples 1 and 3, it decreases.

As described above, the sheet of Comparative Example 3, which was sealed with a resin whose dynamic elastic modulus is outside the range specified in the present invention, had significantly low vibration damping properties, similar to the sheet that was not sealed (Comparative Example 1). I understand.

Claims (1)

[Claims] 1 Dynamic elastic modulus at 120°C is at least 5 x 10
A damping material made by integrating a fibrous material mainly made of lead fibers whose intertwined points are joined with a resin with a tensile strength of ^3 kg/cm^2 and a polymeric substance.