JP3310433B2 - Polyurethane - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyurethane exhibiting excellent vibration damping properties in a wide temperature range around normal temperature.

[0002]

2. Description of the Related Art In recent years, the industry has been actively working on environmental protection, and noise reduction measures have been given particular importance. As part of such noise reduction measures,
Attention has been focused on various damping materials. The primary evaluation of these damping materials was tan δ obtained from dynamic viscoelasticity measurement.
(Loss tangent). T near normal temperature
In addition to the large an δ, t
A material having a large an δ can exhibit excellent vibration absorbing properties in a wide range of use environments, and is therefore expected as a vibration damping material having a wide application range.

[0003]

In the polyurethane industry, polyurethanes having excellent vibration damping properties as described above have been developed. However, even if conventional polyurethanes can exhibit a large tan δ, , Large tan δ is limited to a narrow range. An object of the present invention is to provide a polyurethane excellent in vibration damping properties that not only has a large tan δ near normal temperature but also maintains a large tan δ over a wide temperature range.

[0004]

According to the present invention, an object of the present invention is to provide a polyurethane obtained by polymerizing a polymer diol, an organic diisocyanate and a chain extender, wherein at least a part of the polyurethane is obtained. Has the following general formula (I)

[0005]

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[Wherein, m and n each represent an integer of 1 to 6 (where the sum of m and n is 2 to 10)]

A polyester diol having a glycol component containing an aliphatic glycol component represented by the formula: wherein at least a part of the chain extender has the following general formula (II):

[0008]

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This is achieved by providing a polyurethane characterized by being tricyclodecane dimethanol represented by the formula:

At least a part of the high molecular diol used in the present invention has at least a part of a glycol component as an aliphatic glycol component represented by the above general formula (I) [hereinafter sometimes referred to as a glycol component (I). ] Is a polyester diol. The glycol component (I) has the following general formula

[0011]

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Wherein m and n are as defined above.

A structural unit which can be derived from an aliphatic glycol represented by the following formula, for example, 3-methyl-1,
Structural units that can be derived from 5-pentanediol, 2-methyl-1,8-octanediol, 2-methyl-1,3-propanediol, and the like. These glycol components (I) may contain two or more kinds as necessary. Since at least a part of the glycol component in the polyester diol is the glycol component (I), the obtained polyurethane can exhibit excellent vibration damping properties over a wide temperature range around room temperature. From this viewpoint, the glycol component (I) preferably accounts for 50% by mole or more of all the glycol components in the polyester diol, and more preferably 70% by mole or more. A glycol component other than the glycol component (I) may coexist in the polyester diol,
For example, neopentyl glycol, 2,2-diethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-ethyl-1,3
A structural unit which can be derived from -hexanediol, 3,3-dimethylolheptane and the like. Examples of the dicarboxylic acid component that constitutes the polyester diol together with the glycol component include an aliphatic dicarboxylic acid component and an aromatic dicarboxylic acid component, and an aliphatic dicarboxylic acid component is preferable. As the aliphatic dicarboxylic acid,
Saturated aliphatic dicarboxylic acids known to be commonly used in polyurethane production are preferred, and as typical examples, adipic acid, azelaic acid, sebacic acid,
Dodecane diacid and the like. Further, a polyol having three or more functional groups may be used together within a range that does not reduce the vibration damping properties, but the amount is preferably 5 mol% or less based on all glycol components. The polyester diol preferably has a number average molecular weight in the range of 500 to 10,000, more preferably in the range of 1500 to 6000.

From the viewpoint that the obtained polyurethane has good vibration damping properties, it is preferable that 50 mol% or more of the polymer diol is the polyester diol. The polymer diol may contain a polymer diol other than the above-mentioned polyester diol (for example, a polyester diol other than the above-mentioned polyester diol, polycarbonate diol, polyether diol), but the amount thereof is 50 mol% of the total amount of the polymer diol. The following is preferred.

The tricyclodecane dimethanol represented by the above formula (II) in the chain extender of the present invention [hereinafter sometimes referred to as compound (II)] includes, for example, 3,8-bis (hydroxymethyl ) Tricyclo [5.2.1.0 ² , ⁶ ] decane, 3,9-bis (hydroxymethyl) tricyclo [5.2.1.0 ² , ⁶ ] decane, 4,8-bis (hydroxymethyl) tricyclo [5.2.1.0 ² , ⁶ ] tricyclo [3- or 4-position substituted with one hydroxymethyl group and 8-position or 9-position substituted with one hydroxymethyl group such as decane 5.2.1.0 ² , ⁶ ] decane is preferred. Compound (II) may be a mixture of isomers included therein. The compound (II) is one of the total chain extenders used.
It preferably accounts for 0 mol% or more, more preferably 30 to 100 mol%, and still more preferably 50 to 100 mol%. By using the compound (II) as a chain extender, the obtained polyurethane has good damping properties, and the higher the content of the compound (II) in the used chain extender, the better the damping properties.

The chain extender contains 100 mol% of the compound (II)
May be included, but may further contain other compounds. The chain extender that can be used in common with the compound (II) may be any compound having two hydrogen atoms capable of reacting with isocyanate in the molecule, and can be generally used as a chain extender in polyurethane production. Low molecular weight diols such as aliphatic diols, alicyclic diols, and aromatic ring-containing diols can be used. Representative examples of chain extenders that can be used in combination include ethylene glycol, 1,2-propanediol, 1,4-butanediol, neopentyl glycol, 2,2-diethyl-1,3-propanediol, and 2-butyl-2. Aliphatic diols such as -ethyl-1,3-propanediol and 3-methyl-1,5-pentanediol; and aromatic ring-containing diols such as 1,4-bis (β-hydroxyethoxy) benzene. . Among these, neopentyl glycol,
Preferred are branched aliphatic diols such as 2,2-diethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, and 3-methyl-1,5-pentanediol.

Further, as the organic diisocyanate,
4,4′-diphenylmethane diisocyanate, p-phenylene diisocyanate, tolylene diisocyanate, 1,5-naphthylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate,
Organic diisocyanates known to be generally usable in polyurethane production, such as isophorone diisocyanate and 4,4'-dicyclohexylmethane diisocyanate, are exemplified.

In the production of polyurethane, 0.9 to 1.3 mol of isocyanate groups per mol of active hydrogen atoms, based on the total amount of active hydrogen atoms contained in the polymer diol and the chain extender, Preferably 0.95-
It is preferred to use the organic diisocyanate in such a ratio as to give 1.10 mol.

With respect to a method for producing a polyurethane by polymerizing a polymer diol, an organic diisocyanate and a chain extender, known urethanization techniques such as melt polymerization and solution polymerization can be employed.

The polyurethane of the present invention is prepared in an N, N-dimethylformamide solvent at a concentration of 0.5 g / dl and at a temperature of 30.
The logarithmic viscosity based on the solution viscosity measured at the condition of 0 ° C is 0.
It is desirable to be in the range of 2 to 1.8 dl / g.

In the polymerization process or after the polymerization, a coloring agent, a flame retardant, an ultraviolet absorber, an antioxidant, a hydrolysis resistance improver,
Various additives such as an antifungal agent; various fibers such as glass fiber and polyester fiber; inorganic substances such as talc and silica; various coupling agents may be appropriately selected and blended.

Since the polyurethane of the present invention can exhibit excellent vibration damping properties over a wide temperature range, it can be used as a damping material in housing-related fields such as interior materials for houses; transport equipment such as ships and automobiles; It can be used for office equipment.

[0023]

The present invention will be described below in detail with reference to examples. Note that the logarithmic viscosity and the vibration damping characteristics (tan
The measurement of δ) was performed by the following methods.

(1) Measurement of Logarithmic Viscosity The polyurethane solution viscosity was measured in an N, N-dimethylformamide solvent at a concentration of 0.5 g / dl and a temperature of 30 ° C., and the logarithmic viscosity was determined based on the solution viscosity. did.

(2) Vibration Suppression Characteristics (tan δ) A dynamic viscoelasticity measuring apparatus [DVE, manufactured by Rheology Co., Ltd.] was used for a test piece prepared from a film having a thickness of 0.1 mm.
And the temperature dispersion of the storage elastic modulus E ′ and the loss elastic modulus E ″ were measured at a frequency of 11 Hz and a heating rate of 3 ° C./min, and tan δ (E ″ / E ′) (dynamic (A measure of the hysteresis loss, which is a measure of how external vibrational energy is converted to thermal energy). Maximum value of tan δ (tan δ peak value)
And its temperature (tan δ peak temperature), and ta
The width of the temperature range in which nδ is 0.2 or more (tan δ ≧ 0.
2 temperature ranges). Polyurethane having a large tan δ peak value and a tan δ peak temperature near normal temperature can show excellent vibration damping performance at a temperature near normal temperature. Further, polyurethane having a large value of tan δ ≧ 0.2 temperature width can exhibit good vibration damping performance over a wide temperature range.

The compound used in the examples was
These are indicated by the abbreviations shown in Table 1 below.

[0027]

[Table 1]

Example 1 PMPA (number average molecular weight 30
00), TCDDM and MDI, PMPA :: TC
DDM: MDI molar ratio of 1: 3.74: 4.74 (molar number of isocyanate groups per mole of active hydrogen atoms: 1.00; nitrogen atom content based on elemental analysis: (2.7% by weight) and melt-polymerized at 230 ° C. The resulting polyurethane was pelletized, dehumidified and dried at 80 ° C for 20 hours, and hot-pressed at 220 ° C to produce a 0.1 mm thick film.
The dynamic viscoelasticity was measured.

[Examples 2 to 4, Comparative Examples 1 to 4] The polymer polyol, diisocyanate and chain extender shown in Table 2 were used in the proportions shown in Table 2 (the ratio of isocyanate groups per mole of active hydrogen atom). (Mol number: 1.00; nitrogen content based on elemental analysis: 2.7% by weight), melt polymerization and pelletization were performed in the same manner as in Example 1 to obtain polyurethane pellets. The obtained polyurethane was formed into a film in the same manner as in Example 1, and the film was evaluated. The results shown in Table 2 were obtained.

[0030]

[Table 2]

From Table 2 above, the polyurethane of the present invention is:
the tan δ peak value is high (for example, 1 or more), the tan δ peak temperature is around normal temperature (for example, about 5 to 20 ° C.),
Moreover, the value of the temperature range of tan δ ≧ 0.2 is large (for example, 9
0 ° C. or higher), it can be seen that excellent vibration damping characteristics can be exhibited not only near normal temperature but also over a wide temperature range (Examples 1 to 4). On the other hand, in the polyurethanes other than the present invention, the tan δ peak temperature is low, and the tan δ peak value and the value of the tan δ ≧ 0.2 temperature range are small (Comparative Example 1).
And 3) or tan δ peak value and tan δ ≧ 0.
(2) Since the temperature width is small (Comparative Example 2) or the tan δ peak temperature is low and the tan δ ≧ 0.2 temperature width is small (Comparative Example 4), excellent control over a wide temperature range around room temperature is achieved. It can be seen that vibration characteristics cannot be exhibited.

[0032]

According to the present invention, there is provided a polyurethane capable of exhibiting excellent vibration damping characteristics over a wide temperature range around room temperature.

Continuation of the front page (56) References JP-A-62-39613 (JP, A) JP-A-62-22817 (JP, A) JP-A-53-6399 (JP, A) JP-A-48-56253 (JP) , A) JP-A-2-302418 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 18/00-18/87

Claims (1)

(57) [Claims] 1. A polyurethane obtained by polymerizing a polymer diol, an organic diisocyanate and a chain extender, wherein at least a part of the polymer diol has the following general formula (I): [Wherein, m and n each represent an integer of 1 to 6 (where the sum of m and n is 2 to 10)], and is a polyester diol having a glycol component including an aliphatic glycol component. And at least a part of the chain extender has the following general formula (II): Polyurethane characterized by being tricyclodecane dimethanol represented by the formula: