JPH0543793A - Polyurethane composition and member therefrom - Google Patents

Abstract

PURPOSE:To provide the title composition excellent in vibrational energy absorptivity. CONSTITUTION:The objective composition can be obtained by incorporating (A) 100 pts.wt. of a polyurethane with (B) 5-200 pts.wt. of a phthalic ester of the formula (R1 and R2 are each 3-6C monocyclic hydrocarbon) and/or (C) 3-200 (pref. 10-100) pts.wt. of a petroleum resin prepared by polymerization of 5-9C olefins in a mixed state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is used in various fields such as transportation equipment, precision electronic equipment, and acoustic equipment for the purpose of improving the reaction speed and measurement accuracy and the sound quality by controlling vibration. And a polyurethane resin composition having excellent vibration energy absorption performance.

[0002]

2. Description of the Related Art Conventionally, butyl rubber and polyurethane have been most often used as vibration energy absorbers. Recently, polynorbornene and special urethane elastomers have been found to have higher performance, and have been attracting attention. The primary evaluation of these vibration energy-absorbing materials is the storage elastic modulus (E ′) and loss coefficient (tan δ = loss elastic modulus (E ″) / determined by viscoelasticity measurement of the material.
Storage modulus (E ')).

For designing a vibration energy absorbing material, the larger the loss coefficient is, and the storage elastic modulus has an optimum value depending on the form used. These two
The two factors are usually highly temperature dependent. That is, the storage elastic modulus gradually decreases as the temperature rises, and usually sharply decreases from the temperature range exceeding the glass transition point. Further, the loss coefficient shows the highest value in the temperature range exceeding the glass transition point, but generally tends to decrease in the temperature range before and after that.

Therefore, conventionally, the standard required for such a vibration energy absorbing material has been to have a high loss coefficient in the temperature range in which the material is used. On the other hand, the storage elastic modulus can be adjusted to an optimum value because the value can be adjusted in a considerable range by adding an inorganic or metallic filler, a softening agent, or rubber. Therefore, butyl rubber, polynorbornene, and special urethane elastomer have excellent loss coefficients of tan δ = 1.4, 2.8, and 1.3, respectively. However, these materials were difficult to process and form, and their use range was limited.

On the other hand, polyurethane is widely used in foams, elastic bodies, paints, adhesives, elastic fibers, synthetic leather and the like, and can impart vibration absorbing characteristics in various forms. Moreover, polyurethane is compatible with polyvinyl chloride (PVC) -based resin, and it is possible to exhibit vibration absorbing characteristics at any temperature depending on the mixing ratio. In the case of PVC, its loss factor has a peak value of about 1.1. However,
In the case of thermoplastic polyurethane, about 0.5 and its peak value are smaller than PVC, and when blended with PVC, PV
As a result, the value of C is lowered.

This value is too low as compared with the above-mentioned rubber elastomer. Therefore, a thermoplastic resin having a high loss factor, which is excellent in processability and economy, is being demanded.

[0007]

DISCLOSURE OF THE INVENTION The present invention makes use of the characteristics of polyurethane and also provides excellent vibration energy.
An object is to provide a polyurethane composition having absorption performance.

[0008]

SUMMARY OF THE INVENTION In view of the above-mentioned current situation, the inventors of the present invention have made extensive studies, and as a result, completed the present invention.

That is, phthalic acid ester 5-2 having the structure of (I) below with respect to 100 parts by weight of polyurethane
The present invention relates to a polyurethane composition comprising 00 parts by weight and / or 3 to 200 parts by weight of a petroleum resin, and a vibration energy absorbing material containing the composition.

[0010]

[Chemical 2] (R ₁ , R ₂ : C _{3 to} C ₆ Monocyclic Hydrocarbon) The details will be described below.

The polyurethane used in the present invention has a urethane bond in its molecule, and is mainly produced by reacting a diisocyanate with a polyhydroxy compound (polyol). For example, the diisocyanates include tolylene diisocyanate and diphenylmethane-4,4 '.
-Diisocyanate, 1,5-naphthalene diisocyanate and the like. There is no problem in using polyisocyanates, regenerated isocyanates, non-yellowing isocyanates, and the like. On the other hand, examples of the polyhydroxy compound include polyesters and polyethers whose molecule ends are -OH.

The phthalic acid ester having the structure of the general formula (I) is a compound in which R ₁ and R ₂ are C _{3 to} C ₆ monocyclic hydrocarbons. R ₁ and R ₂ may be the same or different, and hydrogen on the ring may be substituted with another substituent. Specific examples thereof include dicyclohexyl phthalate, dimethyl cyclohexyl phthalate, diphenyl phthalate and the like, and dicyclohexyl phthalate is preferable from the viewpoint of economy and workability.

From the viewpoints of processability and economy, the amount of addition is preferably 5 parts by weight or more and 200 parts by weight or less, more preferably 10 parts by weight or more and 100 parts by weight or less with respect to 100 parts by weight of polyurethane. If it is less than 5 parts by weight, the loss factor is not so improved, and if it is added in excess of 200 parts by weight, workability is extremely deteriorated.

On the other hand, the petroleum resin used in the present invention is C
₅ is obtained by polymerizing leave olefins mixed state of -C _9. However, although the maximum value of the loss coefficient is greatly improved by the addition of petroleum resin, the degree of the effect is considerably different depending on the composition and the molecular weight. That is, it is preferable that the petroleum resin contains 50% by weight or more of C ₉ component indene and styrene, and it is more preferable that the ratio of indene and styrene be half or more of styrene. The number average molecular weight is preferably 500 or more and 1500 or less. If the value is out of these ranges, the value of loss factor decreases.

The amount of addition is 3 parts by weight or more and 200 parts by weight or less, further 10 parts by weight with respect to 100 parts by weight of polyurethane.
It is preferably not less than 100 parts by weight and not more than 100 parts by weight. If it is less than 3 parts by weight, the loss factor is not so improved, and if it is added in excess of 200 parts by weight, the workability is extremely lowered.

The above-mentioned (I) phthalate ester and petroleum resin exhibit the same effect when they are used alone or as a mixture.

The polyurethane composition according to the present invention includes an inorganic filler represented by calcium carbonate and talc, a flame retardant represented by antimony trioxide and zinc borate, and a vibration energy absorbing material represented by mica and graphite. Flaky fillers and the like that are often used for can be added as required.

If necessary, various rubbers used for modifying polyurethane, polyvinyl chloride resin, etc. may be blended.

The polyurethane composition according to the present invention can be molded freely by the conventional methods of molding polyurethane such as casting, kneading, injection molding and extrusion molding.

Further, a foaming agent such as CO ₂ , freon, methylene chloride or pentane, or a cell size controlling agent such as a silicone resin or an emulsifier may be used in the composition to form a polyurethane foam.

The composition can also be used as a paint or adhesive made of polyurethane.

The vibration energy absorbing material obtained according to the present invention has high accuracy in the manufacturing process of a supporting member, an electronic part manufacturing line, etc. in which the accuracy is affected by vibration such as precision electronic equipment and precision measuring equipment. It can be used as a vibration-proof material for required equipment, fixed members such as packing and gaskets, and laminated members such as audio equipment. In addition, it can be attached directly to areas of high vibration such as automobiles and industrial equipment to suppress vibration, or can be used in combination with other materials such as wood and inorganic materials such as metal materials such as stainless steel plates and aluminum plates. it can.

[0023]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited to these examples.

Example 1 100 parts by weight of thermoplastic polyurethane (9X05, manufactured by Nippon Elastollan), dicyclohexyl phthalate (DCHP) as a phthalate ester [Osaka Organic Chemical Co., Ltd.]
20 parts by weight were roll-kneaded at a temperature of 185 ° C. for 5 minutes to obtain a target composition.

Example 2 An exact same system was mixed except that 20 parts by weight of petroleum resin (Petcole LX-HS) [manufactured by Toso Co., Ltd.] was used in place of DCHP in Example 1, and the temperature was changed. The mixture was roll-kneaded at 185 ° C. for 5 minutes to obtain the desired composition.

Example 3 A target composition was obtained by the same procedure as in Example 1 except that 50 parts by weight of DCHP was used.

Example 4 A petroleum resin (Petcole LX-H) was added to the system of Example 1.
S) The target composition was obtained by the same procedure as in Example 1 except that 20 parts by weight was added.

Comparative Example 1 Only the thermoplastic polyurethane used in Example 1 was roll kneaded at a temperature of 185 ° C. for 5 minutes.

Comparative Example 2 By the same procedure as in Example 1, except that 20 parts by weight of di-2-ethylhexyl phthalate (DOP, Vinizerizer 80) [manufactured by Kao Corporation] was used instead of DCHP. The desired composition was obtained.

[Evaluation of loss coefficient (tan δ)] Example
The composition obtained in each of the comparative examples was rolled to 200 μm.
Taking out as a thick sheet, using a viscoelasticity analyzer RSAII (manufactured by Rheometrics Fast), which is a measuring device based on the non-resonance type forced vibration method, a heating rate of 2 ° C./min, a measuring frequency The loss coefficient was measured at 10 Hz. Table 1 shows the peak value of the loss coefficient and the temperature at that time.

[0031]

[Table 1]

[0032]

As is apparent from the above description, according to the present invention, polyurethane and a specific phthalate ester and / or
Alternatively, a vibration energy absorbing material having a high loss coefficient can be obtained by compounding petroleum resin in a specific ratio.

Claims (2)

[Claims] 1. A polyurethane composition comprising 5 to 200 parts by weight of a phthalic acid ester having the structure (I) below and / or 3 to 200 parts by weight of a petroleum resin per 100 parts by weight of polyurethane. [Chemical 1] _{(R 1, R 2:} monocyclic hydrocarbon of C 3 -C ₆₎ 2. A vibration energy absorbing material comprising the composition according to claim 1.