JP3466369B2 - Method for producing polyurethane - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyurethane exhibiting excellent vibration damping characteristics in a wide temperature range around normal temperature. 2. Description of the Related Art In recent years, with the development of the automobile industry and the electric industry, there has been an increasing demand for environmental improvement with respect to vibration and noise. Above all, importance has been placed on measures to absorb vibration and reduce noise. ing. As a part of such vibration absorption measures and noise reduction measures, various types of vibration suppression performance (vibration absorption performance,
Materials such as rubbers and elastomers having noise prevention performance have been developed. Generally, the evaluation of the vibration damping performance of a material such as rubber or elastomer is widely performed using a value of a loss coefficient (tan δ) obtained by measuring a viscoelastic modulus of the material. Since a material having a large loss coefficient and a large loss coefficient over a wide temperature range can exhibit excellent vibration damping performance in a wide range of use environments, it is expected as a vibration damping material having a wide applicable range. [0003] As a material having excellent vibration damping performance using a polyurethane elastomer, 1,4-
Polyurethane using cyclohexane dimethanol as a chain extender component (see Japanese Patent Application Laid-Open No. 7-292061)
A vibration damping material consisting of Some of these conventional polyurethane elastomers exhibit large loss factor values at room temperature. An object of the present invention is to provide a material capable of exhibiting excellent vibration damping performance in a wide range of use environments, and has a large loss coefficient near room temperature and a wide temperature range. An object of the present invention is to newly provide a polyurethane having a large loss coefficient and excellent vibration damping performance. The present inventors have conducted intensive studies with the aim of solving the above-mentioned problems, and as a result, have completed the present invention. That is, the present invention provides a method for producing a polyurethane, which comprises using cyclooctane dimethanol as a chain extender component when producing a polyurethane by reacting a polymer polyol component, a polyisocyanate component and a chain extender component. It is. According to the present invention, it is possible to produce a polyurethane excellent in vibration damping performance, which has a large value of the loss coefficient near normal temperature and maintains a large value of the loss coefficient over a wide temperature range. The polyurethanes obtained according to the invention are very useful in a wide variety of applications. In the present invention, cyclooctane dimethanol is used as the chain extender component. From the viewpoint of the vibration damping performance of the obtained polyurethane, at least 20 mol% of the chain extender component is cyclooctane dimethanol. Is preferred. As the content of cyclooctanedimethanol in the chain extender component increases, the obtained polyurethane tends to have improved vibration damping performance. [0008] The content of cyclooctane dimethanol in the chain extender component is more preferably at least 30 mol%, even more preferably at least 50 mol%. When the mol%, that is, the total amount of the chain extender is cyclooctane dimethanol, the obtained polyurethane has the best vibration damping performance. Examples of cyclooctane dimethanol include 1,3-cyclooctane dimethanol and 1,4-cyclooctane dimethanol.
Although isomers such as cyclooctane dimethanol and 1,5-cyclooctane dimethanol exist, in the present invention,
Any of these isomers can be used as cyclooctane dimethanol. In the present invention, a single isomer may be used as cyclooctane dimethanol, or a mixture of two or more isomers may be used. Cyclooctane dimethanol is, for example,
Industrial production is achieved by hydroformylating 1,5-cyclooctadiene, which is mass-produced and available at low cost, to produce cyclooctanedicarbaldehyde, and reducing the resulting cyclooctanedicarbaldehyde by a known method such as hydrogenation. It can be manufactured in a special way. The chain extender component used in the present invention may contain a compound having two or more active hydrogen atoms in addition to cyclooctanedimethanol. The compound having two or more active hydrogen atoms is a known low-molecular compound conventionally used as a chain extender component in the production of polyurethane, and is a low-molecular compound having two or more active hydrogen atoms that react with isocyanate. Molecular compounds are preferably used, for example, ethylene glycol,
1,2-propanediol, 1,4-butanediol,
2-methyl-1,4-butanediol, neopentyl glycol, 3-methyl-1,5-pentanediol,
2,2-diethyl-1,3-propanediol, aliphatic diols such as 2-butyl-2-ethyl-1,3-propanediol; cyclohexanedimethanol, alicyclic diols such as tricyclodecane dimethanol 1,4-
Examples thereof include aromatic ring-containing diols such as bis (β- hydroxyethyl ) benzene. Among them, 2-methyl-1,4-butanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol,
Aliphatic diols having a branch such as -butyl-2-ethyl-1,3-propanediol; 1,4-cyclohexanedimethanol, 3 (or 4), 8 (or 9) -dihydroxymethyltricyclo [ 5, 2 , 1,0 ^2,6 ]
Since alicyclic diols such as decane, it does not lower the damping performance of the resulting polyurethane are particularly preferred. These low molecular compounds may be used alone or in combination of two or more. [0012] The polymer polyol component used in the present invention is not particularly limited, and examples thereof include polyester polyol, polyether polyol, polycarbonate polyol, polyester polycarbonate polyol,
Any of high molecular polyols conventionally used in the production of polyurethane, such as polyester polyether polyol, butadiene-based and / or isoprene-based both-end diol or hydrogenated product thereof, can be used. The above-mentioned high molecular polyol component preferably has a number average molecular weight in the range of 500 to 10,000, more preferably in the range of 1500 to 6000. The polymer polyol component may be used alone or as a mixture of two or more. In addition, as long as the vibration damping performance is not reduced, a small amount of a trifunctional or higher functional polyol component may be used in combination. The polyisocyanate component used in the present invention is not particularly limited, and any of the polyisocyanate components conventionally used in the production of polyurethane may be used. For example, 4,4'-diphenylmethane diisocyanate , Tolylene diisocyanate, phenylene diisocyanate, 1,5-naphthylene diisocyanate, 3,3'-dichloro-4,4'-diphenylmethane diisocyanate, xylylene diisocyanate,
Examples thereof include aromatic or alicyclic diisocyanates such as aromatic diisocyanates such as toluylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and hydrogenated xylylene diisocyanate. These polyisocyanate components may be used alone or in combination of two or more. Further, a polyisocyanate having three or more functionalities can be used as long as the vibration damping performance is not reduced. In producing the polyurethane by reacting the high molecular polyol component, the polyisocyanate component and the chain extender component, the mixing ratio of each component is appropriately determined in consideration of the hardness to be imparted to the target polyurethane. It is determined that the isocyanate groups per mole of the active hydrogen atoms is 0.9 to 1.3 moles based on the total amount of the active hydrogen atoms of the polymer polyol component and the chain extender component. It is preferable to use the polyisocyanate component in an appropriate ratio, and it is more preferable to use the polyisocyanate component in such a ratio that the isocyanate group per mole of the active hydrogen atom is 0.95 to 1.1 mole. The polyurethane obtained according to the present invention has a logarithmic viscosity when measured at 30 ° C. as an N, N-dimethylformamide (hereinafter abbreviated as DMF) solution having a polyurethane concentration of 0.5 g / dl. 0.4-2dl
/ G is desirable. In the present invention, a catalyst, a reaction accelerator, a foaming agent, an internal mold release agent, a filler, a reinforcing agent, a dye / pigment , a colorant, a flame retardant, an ultraviolet ray, which are usually used in the production of polyurethane. Various additives such as absorbents, antioxidants, hydrolysis resistance improvers, fungicides, stabilizers, etc., various fibers such as glass fibers and polyester fibers, inorganic substances such as talc and silica, and various coupling agents etc. The components can be used as needed. In the present invention, as a method for producing a polyurethane by reacting a high molecular polyol component, a polyisocyanate component and a chain extender component, any known urethanization reaction techniques such as melt polymerization and solution polymerization can be used. , Prepolymer method and one-shot method. A specific example of the method for producing the polyurethane of the present invention is as follows. A high molecular polyol component and a chain extender component are mixed and heated to 40 to 100 ° C., and the resulting mixture is mixed with active hydrogen in the mixture. After adding a polyisocyanate component in an amount such that the molar ratio of atoms to isocyanate groups is 1: 1 to 1: 1.5 and stirring for a short time, for example, 50 to 16
A method of producing polyurethane by heating to 0 ° C, a method of producing a polyurethane by kneading a mixture of a polymer polyol component, a chain extender component and a polyisocyanate component at a high temperature of, for example, 180 to 260 ° C, and multi-screw extrusion. A method of continuously supplying a polymer polyol component, a chain extender component, a polyisocyanate component, and the like to an extruder such as an extruder and continuously melt-polymerizing at a high temperature of, for example, 180 to 260 ° C. to produce a polyurethane; And a method in which a polyurethane forming reaction between a chain extender component and a polyisocyanate component is performed in an organic solvent. Among these, when producing polyurethane by the above-mentioned method, by controlling the concentrations of the high molecular weight polyol component, the chain extender component and the polyisocyanate component, a high molecular weight polyurethane can be easily produced. . At this time, the concentrations of the polymer polyol component, the chain extender component and the polyisocyanate component are 10 to 40.
It is preferably in the range of% by weight. The organic solvent can be used dimethylformamide, dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, toluene, methyl ethyl ketone, ethyl acetate, ethyl cellosolve. These solvents may be used alone or in combination of two or more. The polyurethane obtained according to the present invention exhibits excellent vibration damping performance in a wide temperature range around room temperature, and is therefore required for mechanical parts, automobile parts,
Housing-related parts, electrical equipment materials, packaging materials, sheets, films, rolls, solid tires, belts, tubes, packing materials, shoe soles, sports shoes, sports equipment, elastic fibers, artificial leather, fiber treatment agents, adhesives, coatings Agent,
It can be used for a wide variety of applications such as various binders and paints. The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples. In the following examples and comparative examples, the evaluation of the logarithmic viscosity and the vibration damping performance of the polyurethane was performed by the following methods. A measurement of the logarithmic viscosity of the polyurethane A DMF solution of the polyurethane having a concentration of 0.5 g / dl was prepared, the solution viscosity was measured at 30 ° C., and the logarithmic viscosity was determined based on the solution viscosity. Evaluation of Vibration Suppression Performance of Polyurethane A test piece prepared from a polyurethane film having a thickness of 1 mm was subjected to a dynamic viscoelasticity measurement apparatus (RHEOVIBRO).
N; manufactured by Orientec Co., Ltd.), frequency 11H
z, the storage elastic modulus (E ′) and the loss elastic modulus (E ″) were measured at a heating rate of 3 ° C./min, and the loss coefficient (tan δ = E ″) was measured.
/ E '), and a graph showing the change in the value of the loss coefficient with respect to the temperature was created. Maximum value of loss coefficient (peak value of tan δ)
And the temperature at which the loss coefficient has the maximum value (peak temperature of tan δ), and the temperature at which the value of the loss coefficient is 0.5 or more. Loss factor is used as a measure of vibration damping,
The larger this value is, the better the vibration suppression performance (vibration absorption performance, noise prevention performance, etc.) is. Polyurethane having a loss coefficient peak temperature near normal temperature exhibits excellent vibration damping performance at temperatures near normal temperature. Furthermore, polyurethane having a wider temperature range in which the loss coefficient is 0.5 or more can exhibit excellent vibration damping performance over a wider temperature range. The compounds used in Examples and Comparative Examples are represented by the following abbreviations. CODM: cyclooctane dimethanol CHDM: 1,4-cyclohexane dimethanol (cis, trans mixture, cis / trans = 30/70) BD: 1,4-butanediol MDI: 4,4′-diphenylmethane diisocyanate PMPA: 3- Polyester polyol having a number average molecular weight of 2,000 obtained from methyl-1,5-pentanediol and adipic acid (trade name: Clapol P-2010,
PNOA: Polyester polyol having a number average molecular weight of 2,000 obtained from a mixture of 2-methyl-1,8-octanediol (35%) and 1,9-nonanediol (65%) and adipic acid ( Product name: PNOA-2010,
PBA: Polyester polyol having a number average molecular weight of 2,000 obtained from 1,4-butanediol and adipic acid (trade name: Klapol A-2010, manufactured by Kuraray Co., Ltd.) PCL: Poly-ε-caprolactone (Number average molecular weight 2000) (trade name: PLACCEL220, manufactured by Daicel Chemical Industries, Ltd.) PHC: poly (hexamethylene carbonate) (number average molecular weight 2000) (trade name: Nipporan 980N,
PTMG: polytetramethylene glycol (number average molecular weight 2000) (trade name: PTG-2000, manufactured by Hodogaya Chemical Industry Co., Ltd.) Reference Example (Synthesis of CODM) Thermometer In a stainless steel autoclave having a content of 500 ml and equipped with an electromagnetic stirrer and a gas inlet, 0.028 g of rhodium dicarbonylacetylacetonate and 1.13 g of triphenylphosphine were dissolved in toluene 10
A catalyst solution obtained by dissolving in 0 ml and 100 ml of 1,5-cyclooctadiene were charged in a hydrogen / carbon monoxide mixed gas (molar ratio = 1/1) atmosphere. Next, a hydrogen / carbon monoxide mixed gas (molar ratio = 1/1) was introduced into the autoclave, the internal pressure was adjusted to 90 absolute pressure, and the internal temperature was raised to 60 ° C. with stirring. A hydrogen / carbon monoxide mixed gas (molar ratio = 1/1) was continuously supplied so that the internal pressure was maintained at 90 absolute pressure, and the internal temperature was maintained at 60 to 70 ° C. for 3 hours. Then, the internal temperature was raised to 90 ° C., and the mixture was further stirred for 3 hours to complete the reaction. When the obtained reaction mixture was analyzed by gas chromatography, unreacted raw materials 0.5
%, Monoaldehyde compound 1.7%, dialdehyde compound
3%. The catalyst and toluene were removed from the reaction mixture using a wiper thin film still to obtain a hydroformylation reaction solution. In a 300 ml stainless steel autoclave equipped with a thermometer, an electromagnetic stirrer, and a gas inlet, 80 m of the hydroformylation reaction solution obtained above was placed.
1, 80 ml of isopropyl alcohol and 1.6 g of Raney nickel were charged. Next, hydrogen gas was introduced into the autoclave, and while the hydrogen gas was continuously supplied so that the internal pressure was maintained at 10 absolute pressure, the internal temperature was reduced to 10 while stirring.
The temperature was raised to 0 ° C. The reaction was completed by stirring for 5 hours while maintaining the internal temperature at 100 ° C. When the obtained reaction mixture was analyzed by gas chromatography, no unreacted aldehyde was detected. The reaction mixture was filtered to remove Raney nickel, and isopropyl alcohol and high-boiling substances were removed from the obtained filtrate using a wiper-type thin-film evaporator to obtain a colorless transparent viscous liquid. This colorless, transparent and viscous liquid is subjected to an internal temperature of about 200 ° C. and a reduced pressure of 1 to 5 t.
Distillation was performed under orr conditions to obtain a fraction at 146 to 160 ° C. to obtain 70 g of a colorless and transparent liquid. According to ¹ H-NMR analysis and mass spectrometry,
This liquid was confirmed to be cyclooctane dimethanol. The cyclooctane dimethanol (CODM) thus obtained was used in the following Examples and Comparative Examples. Example 1 In a reaction vessel, PMPA (number average molecular weight 2000) 0.0
5 mol (100 g), MDI 0.2 mol (50 g), C
0.15 mol (25.8 g) ODM and DMF530
g, and reacted at 80 ° C. for 6 hours to obtain a DMF solution of polyurethane (nonvolatile content: 25%). The logarithmic viscosity of the polyurethane is shown in Table 1. The DMF solution of polyurethane obtained above was cast on a glass plate and dried at 60 to 70 ° C. to obtain a dry polyurethane film. After the polyurethane dry film was finely cut, it was dehumidified and dried at 80 ° C. for 24 hours, and then hot pressed at 220 ° C. to a thickness of 1 m.
m was prepared, and the damping performance was evaluated according to the method described above. Table 1 shows the results. Examples 2 to 8 and Comparative Examples 1 to 3 The procedure of Example 1 was repeated except that the polymer polyol component, polyisocyanate component and chain extender component shown in Table 1 were used. A film was obtained. From the obtained polyurethane dry film, a film having a thickness of 1 mm was prepared in the same manner as in Example 1, and the damping performance was evaluated. Table 1 also shows the evaluation results of the logarithmic viscosity and the vibration damping performance of the polyurethane. [Table 1] From Table 1, it can be seen that the polyurethane of the present invention has a large maximum loss coefficient, is excellent in vibration damping performance, and has a maximum loss coefficient near normal temperature. It can be seen that excellent vibration damping performance is exhibited when performing the above. Moreover, the temperature range where the loss coefficient is 0.5 or more is wide, and excellent vibration damping performance can be exhibited over a wide temperature range. On the other hand, in a polyurethane in which the chain extender component does not contain cyclooctane dimethanol, the temperature at which the loss coefficient has the maximum value is low, and the maximum value of the loss coefficient is small, and the loss coefficient is 0.5 or more. Since the temperature range is also narrow, excellent vibration damping performance cannot be exhibited over a wide temperature range around room temperature. According to the present invention, it is possible to produce a polyurethane excellent in vibration damping performance, which has a large loss coefficient near room temperature and maintains a large loss coefficient over a wide temperature range. it can. The polyurethanes obtained according to the invention are very useful in a wide variety of applications.

Claims (1)

(57) [Claim 1] When producing a polyurethane by reacting a polymer polyol component, a polyisocyanate component and a chain extender component, cyclooctane dimethanol is used as a chain extender component. A method for producing a polyurethane, comprising: