JPS61235418A - Sound-and vibration-proof foam - Google Patents

Abstract

PURPOSE:The title lightweight foam excellent in processability and sound- absorbing and vibration-proof performances, obtained by foaming and organic polyisocyanate and a specified polyol in the presence of a blowing agent, a catalyst, a foam stabilizer, a fluid having a plasticizing effect, etc. CONSTITUTION:The title foam comprising a flexible polyurethane foam is obtained by foaming, by one-shot process, an organic polyisocyanate (A) such as tolylene diisocyanate and at least one polyol (B), such as polyoxyalkylenepolyol of a functionality of 2-3 and an average hydroxyl value of 150-400, in the presence of a blowing agent such as a low-boiling halohydrocarbon, a catalyst such as an amine and 10-100pts.wt. (per 100pts.wt. polyol) fluid having a plasticizing effect (e.g., trisdichloropropyl phosphate).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a soundproof polyurethane foam that has both sound absorption and vibration damping performance.

[Conventional technology]

Conventionally, polyurethane foam has a continuous fine cell structure and has been widely used as an excellent porous sound-absorbing material in equipment such as automobiles and office equipment, and in buildings.

In general, noise from automobiles, factory machinery, office equipment, etc. is not only transmitted through the air from the sound source, but also due to the mechanical vibration of the car body and the structure of the equipment, and the sound is radiated from there. There is. Therefore, in order to prevent these noises, it is necessary not only to absorb sound with a sound-absorbing material, but also to dampen the vibration of the body, cover, etc. using the sound-absorbing material itself. However, polyurethane foam, which has traditionally been used as a sound-absorbing material, has a low vibration energy absorption capacity and low damping performance, so it was insufficient as a material to reduce noise caused by mechanical vibrations as described above. There are various rubber-like substances, thermoplastic resins, etc., with fillers such as mica, carbon black, and calcium carbonate added, but they are expensive and
Moreover, it was heavy, and even if it exhibited vibration damping performance, it did not have sound absorption performance. In addition, measures have been taken to add fillers such as those mentioned above to polyurethane foam to increase its density and improve its sound insulation performance.
Even in this case, it resulted in an increase in cost and a decrease in physical properties, resulting in an unsatisfactory result. Therefore, as a soundproofing material that has both sound absorption and vibration damping performance, we use composites that combine sound absorption and vibration damping materials, such as polyurethane foam that is post-treated and impregnated with asphalt, or asphalt as a raw material for polyurethane foam. Foam with high viscosity such as foam that is added and foamed together.
Currently, viscoelastic foam is used.

[Problem that the invention seeks to solve]

As mentioned above, asphalt-based foam has both sound absorption and vibration damping performance, but it is extremely inefficient in terms of workability, as processing equipment is contaminated by asphalt during processing such as hot compression molding. Furthermore, it has the disadvantage of high cost. Furthermore, the post-treated asphalt 7 ohm has uneven impregnation, making it difficult to obtain uniform quality.

Furthermore, although it is desirable that soundproofing materials used in vehicles be lightweight, the above-mentioned asphalt foams and various rubbers, resins, etc. with fillers added have large densities and have the problem of being heavy.

The present invention is intended to solve the above-mentioned problems, and aims to provide a soundproof polyurethane foam that is easy to work with, is lightweight, and has both sound absorption performance and vibration distribution performance.

[Means for solving problems]

The soundproofing/dissonance property of the present invention of 7 ohm is obtained when a flexible polyurethane foam is produced by a one-shot method using an organic polyinsyanate and a polyol in the presence of a blowing agent, a catalyst, a foam stabilizer, and other additives. 1i)-i1!) As the polyol component, a polyoxyalkylene polyol which is di- or penta-functional and has an average hydroxyl value of 150 to 400, used alone or in combination of two or more; 1i)-i1! 10 to 10 parts of a fluid having a plasticizing effect per 100 parts by weight of the polyol
0 parts by weight; is characterized by being obtained by adding.

[Effect]

In this case, the polyoxyalkylene polyol used as the polyol component is difunctional or trifunctional, and has an average hydroxyl value of 150 to 400, alone or in combination of two or more,
Preferred is a polyoxyalkylene polyol having a molecular weight of 20 to 300%.

This type of polyoxyalkylene polyol that can be used includes a molecular weight of 20 having a structure in which two or three active hydrogen-containing compounds K, such as ethylene oxide, propylene oxide, epichlorohydrin, etc. are added singly or in random or block addition of two or more kinds. There are 8,000 compounds that can be found in the mouth. Examples of the above 2 to 5 active hydrogen-containing compounds and Citeha, water,
Examples include ethylene glycol, glopylene glycol, butylene glycol, hexylene glycol, glycerin, and trimethylolpropane.

A polyurethane foam obtained using a polyol with a hydroxyl value of less than 150 has a short return time after compression, and also has a low hysteresis loss, which is a foam that lacks so-called high repulsion distribution performance. Addition of a fluid having a plasticizing effect results in a foam with large repulsion and extremely poor vibration damping performance. On the other hand, polyols with a hydroxyl value exceeding 400 have high emergency pressure reactivity and tend to form a closed-cell contracted foam in a typical formulation, making it difficult to control foaming and making it difficult to obtain a good foam.

In addition, even if a polyol with a hydroxyl value of 150 to 400 is used, a foam without adding a fluid having a plasticizing effect,
Although this results in a foam with relatively low repulsion and large hysteresis, the return time after compression is short and excellent soundproofing and vibration distribution performance cannot be obtained.

A fluid with a plasticizing effect has a damping effect, and the amount added is determined by the combination of the number of functional groups and the hydroxyl value of the polyol. If the amount is less than 1 part by weight, the return time after compression may be too short or the return may not return, resulting in failure to obtain desired good physical properties. On the other hand, if more than 100 parts by weight of the fluid is added, it is necessary to use a polyol with a high hydroxyl value in order to obtain the desired foam properties, and such a polyol with a high hydroxyl value may cause reaction. It is difficult to control foaming because it tends to form a closed-cell contracted foam. Therefore, the fluid having a plasticizing effect may be added in an amount of 10 to 100 parts by weight, preferably 20 to 80 parts by weight.

Examples of fluids with a plasticizing effect that can be added include trisdichloropropyl phosphate, trischloroglobyl phosphate 71''+7) halogenated phosphate esters, tricresyl phosphate, triphenyl phosphate, cresyl diphenyl phosphate. Commonly used plasticizers such as phosphoric acid esters and phthalic acid esters, esters such as sebacic acid polyester, adipic acid polyester, trimellitic acid ester, liquid coumaron indene resin, aromatic hydrocarbon resin, etc. Examples include viscous substances.

The incyanate used in the present invention is not particularly limited, and includes incyanates commonly used for the production of polyurethane foam, such as the 2,4-isomer or 2,6-isomer of tolylene diisocyanate, or mixtures thereof. , diphenylmethane diisocyanate, hexamethylene diisocyanate, or naphthalene diisocyanate. From the viewpoint of foaming control, the ratio of 2.4 isomer and 2,6-isomer of tolylene diisocyanate is 65:5.
5 mixture is preferred.

As the blowing agent, water or a low boiling point halogenated hydrocarbon such as Freon-11 or methylene chloride can be used alone or in combination.

Other additives such as amine catalysts and foam stabilizers are not particularly limited.
Those commonly used for the production of polyurethane foams can be used.

The polyurethane foam of the present invention is preferably produced by a one-shot method in which an organic polyisocyanate, a polyol, a catalyst, a blowing agent, an additive, etc. are simultaneously mixed and foamed because it is rational, economical, and can be mass-produced.

〔Example〕

The present invention will be explained in detail below using Examples and Comparative Examples.

Polyurethane foam was manufactured based on the formulation shown in the table.

The resulting 41SIP polyurethane foam was measured for density change, hardness, impact resilience, hysteresis loss, and return characteristics after compression, and the results are also listed in the table. Note that hardness and impact resilience were measured based on JIS K6401. The return characteristics after compression were determined by placing the obtained foam (size SOXSOX 50 m) on an iron plate, placing a disc-shaped lead weight (4 in 6, diameter 100 m) on top of the foam, and crushing it. After leaving it for 30 seconds, the weight was removed, and the time from this point until it returned to its original shape was measured.

Note 1) Polyoxyalkylene triol with an average molecular weight of 700 and a hydroxyl value of 24 [lL4] 2) Polyoxyalkylene triol with an average molecular weight of 1500 and a hydroxyl value of 112.2 3) Polyoxyalkylene triol with an average molecular weight of 3000 and a hydroxyl value of 5 & 1 Polyoxyalkylene triol with an average molecular weight of 400 and a hydroxyl value of 4208 5) Nippon Steel ■Kumaronshi-20 6) Nitto Funka Kogyo-NS"100 7) DABCO 33Lv 8) N-Ethylmorpholine The smaller the impact resilience, the better; Comparative Examples 1 and 2 were large at 17 inches and 45 inches, respectively, whereas Examples 1 to 4 were large.
It was small, 6 to 8 inches.

The larger the hysteresis loss, the better; Examples 1 to 4 are as high as 852 to 89.6%, and Comparative Example 1 is also 94.5%.
However, Comparative Example 2 was small at 4&5 inches. It is preferable for the return time after compression to be in the range of 30 to 240 seconds for soundproofing and vibration isolation performance, but Comparative Example 1 was not compressed at a weight of 6 to 4, and was distorted when further pressure was applied and compressed to 7 ohms. remained and did not completely return to its original state, and returned immediately in Comparative Example 2Fi, whereas Examples 1 to 4 took 52 to 152 seconds.

In addition, the obtained polyurethane foam was subjected to measurement of soundproofing performance. The measurement was carried out by placing a 20 m thick test foam on top of a 5 m thick polyvinyl chloride sheet, placing it on a steel plate with a thickness of α8 mb, and
Vibrating sound was generated on the steel plate in a room maintained at a constant temperature, and the sound pressure level was measured. The results are shown in FIGS. 1 and 2 based on the results obtained using only a 0.811 steel plate without placing the foam.

The soundproofing performance of Example 1 was as shown in Figures 1 and 2.
and 2 is up to 5 dB depending on the frequency compared to Comparative Example 1,
It was superior to Example 5 and 4#'i Comparative Example 2 by up to 4 dB depending on the frequency. 4? Trap, low frequency range 200~
At aoOHz, Examples 1 to 4 were superior to Comparative Examples 1 and 2 in soundproofing performance by 2 to 3 dB. This shows that the polyurethane foam of the example has vibration damping performance in addition to sound absorption performance.

〔Effect of the invention〕

As is clear from the above results, the polyurethane foam of the present invention contains the polyol specified above and a fluid having a plasticizing effect. It can be used as a shaking material. Moreover, since asphalt is not used, the processing equipment is not contaminated by asphalt during processing such as hot compression molding, and there is no reduction in work efficiency. It is lightweight because no filler is used, and it is preferable for applications such as vehicles as it saves energy.

Further, the polyurethane foam of the present invention does not require any special manufacturing equipment, and can be manufactured by a one-shot method using conventional polyurethane foam manufacturing equipment, making it possible to mass produce it at low manufacturing costs. Since it can be reused, it has many advantages such as effective use of resources.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the relationship between the soundproofing effect and frequency of Examples 1 and 2 and Comparative Example 1, and FIG. 2 is a graph showing the relationship between the soundproofing effect and frequency of Examples 5 and 4 and Comparative Example 2. Patent applicant Achilles Co., Ltd. Fang 1 layer table #! LH. Fang 2 illustration Zhou Aiqiu Hz

Claims (1)

[Claims] When producing a flexible polyurethane foam by a one-shot method using an organic polyisocyanate and a polyol in the presence of a blowing agent, a catalyst, a foam stabilizer and other additives, i) as a polyol component, 2 or using a trifunctional polyoxyalkylene polyol having an average hydroxyl value of 150 to 400, alone or in combination of two or more; ii) using a fluid having a plasticizing effect as the polyol 100;
10 to 100 parts by weight; a soundproofing/vibration-damping foam characterized by being obtained by adding 10 to 100 parts by weight;