JPH0597960A - Polyurethane and method for producing the same - Google Patents

Abstract

(57) [Summary] (Modified) [Structure] A polyurethane whose main chain is substantially formed of a polymer polyol and an organic polyisocyanate, wherein the polymer polyol has the following structural units in its molecule. (I) (In the formula, X ₁ and X ₂ are each CH ₂ O— or C ₂
A polyurethane having a number average molecular weight of 500 to 30,000 and containing a group represented by OO-, and n represents 0 or 1. [Effect] The polyurethane of the present invention is excellent in cold resistance, abrasion resistance and mechanical performance. [Chemical 2] [Chemical 3] [Chemical 4]

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyurethane using a novel polymer polyol containing a specific structural unit and having excellent cold resistance, mechanical performance and abrasion resistance, and a method for producing the same.

[0002]

2. Description of the Related Art Polyurethane has a high elastic recovery rate and has many features such as excellent wear resistance and oil resistance, and thus has been attracting attention as a substitute material for rubber and plastic from the past. As a molding material to which a processing method can be applied, it has been used in large amounts in a wide range of applications. Polyurethane is a polymer diol,
It is known that it is preferable to mix and polymerize a chain extender such as diisocyanate and 1,4-butanediol in a mixed state for polymerization.

Polyester polyurethanes, polyether polyurethanes, polycarbonate polyurethanes and the like are known as polyurethanes, and these polyurethanes are used in various applications depending on their respective characteristics. For example, polyether-based polyurethanes are used in applications where hydrolysis resistance is particularly required, but they are extremely inferior in light resistance and oxidative deterioration resistance. On the other hand, polyester-based polyurethane, although inferior in water resistance and mold resistance, is used for applications in which mechanical performance, oil resistance, and wear resistance are particularly required, and polycarbonate-based polyurethane has bending fatigue resistance and In particular, although it is inferior in flex fatigue resistance at low temperatures, it is used in applications where durability is required in addition to the characteristics of polyester. Recently, polyester carbonate polyol-based polyurethane has also been proposed.

In addition to durability such as light resistance and oxidation deterioration resistance,
Polyester-based and polycarbonate-based polyurethanes that are excellent in abrasion resistance and mechanical performance are generally inferior in cold resistance, that is, the rubber elasticity of the polyurethane at low temperatures decreases, so as a polymer polyol component,
Propylene glycol, neopentyl glycol, 3-
Amorphized or low crystallized copolymerized branched diol such as methyl-1,5-pentanediol is used to prevent solidification of the soft segment at low temperature. However, low crystallization or amorphization with these branched diols tends to impair the excellent mechanical properties inherent to polyurethane, such as abrasion resistance.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polyurethane having excellent mechanical performance and abrasion resistance without impairing its flexibility at low temperature. Another object of the present invention is to provide a method for producing the above novel polyurethane.

[0006]

The present inventors have found that a polyurethane using a specific polymer polyol can solve the above problems, and have completed the present invention. That is, the present invention is, firstly, a polyurethane having a main chain substantially formed of a polymeric polyol and an organic polyisocyanate, wherein the polymeric polyol has the following structural unit (I) in the molecule.

[0007]

[Chemical 3]

(Wherein X ₁ and X ₂ are each CH ₂
O- or COO-, and n represents 0 or 1, and has a number average molecular weight of 500 to 30,
000 polyols. In addition, the present invention secondly provides the following structural unit (I) in the molecule.

[0009]

[Chemical 4]

A polymer polyol containing a group represented by the formula (wherein X ₁ , X ₂ and n are as defined above) and an organic polyisocyanate are polymerized. It relates to a manufacturing method.

The polymer polyol used in the production of the polyurethane of the present invention is a polymer polyol containing a group represented by the structural unit (I), and a typical one is a polyester polyol (particularly a polyester diol). ), Polycarbonate polyols (especially polycarbonate diols) and polyester carbonate polyols (especially polyester carbonate diols)
Is. The polymer polyol includes the structural unit (I)
It is essential that a specific alicyclic diol residue and / or alicyclic dicarboxylic acid residue represented by are present, and the present invention achieves its object only when the polymer polyol is used.

When the above-mentioned polymer polyol is produced, an alicyclic compound containing a group represented by the structural unit (I) is used. Specifically, for example, norbornane-2,3
-Dimethanol, norbornane-2,3-dicarboxylic acid and its diester, perhydro-1,4: 5,8-
Examples thereof include dimethanonaphthalene-2,3-dimethanol, perhydro-1,4: 5,8-dimethanonaphthalene-2,3-dicarboxylic acid and its diester. The three-dimensional structure of these compounds may be either cis or trans, or a mixture thereof. Further, the alicyclic structure portion thereof may be an endo-form, an exo-form, or a mixture thereof.

Of these compounds, the dicarboxylic acid diester is a method for reducing the double bond of the product of the Diels-Alder reaction of fumaric acid diester or maleic acid diester with cyclopentadiene (Journal of Polymer Science; Polymer Chemistry Edition, 1972). 10, page 3191), and the dicarboxylic acid is produced by a method of hydrolyzing a dicarboxylic acid diester. Further, the compound containing a hydroxymethyl group is a product obtained by a method of reducing a dicarboxylic acid diester or a Diels-Alder reaction of 2-butene-1,4-diol or a derivative thereof and cyclopentadiene (UK Patent 79).
(See JP-A-6,135, JP-A-3-31230)
Can be produced by a method of reducing.

The alicyclic compound may be used alone or in any combination of two or more kinds. The group represented by the structural unit (I) has an effect of suppressing crystallization of polyurethane, but not only lowers mechanical performance and abrasion resistance but also improves these.

In the production of the polymer polyol used in the present invention, other diols and / or trivalent or higher alcohol components may be used as the alcohol component, if necessary, in addition to the alicyclic compounds described above, within a range not departing from the object of the present invention. The above polyhydric alcohol can be used, and as the dicarboxylic acid component, another dicarboxylic acid or a dicarboxylic acid derivative having ester forming ability can be used.

The content of the group represented by the structural unit (I) in the polymer polyol used in the present invention is 5 weight% of the total amount of the diol, the polyhydric alcohol residue having a valence of 3 or more and the dicarboxylic acid residue. It should be at least%.

Among these, as diols, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1, 8-octanediol, 1,9-nonanediol, 1,10-
Decanediol, 1,12-dodecanediol, neopentyl glycol, propylene glycol, diethylene glycol, 1,4-cyclohexanedimethanol, 2
-Methyl-1,8-octanediol, 3-methyl-
Examples include 1,5-pentanediol and neopentyl glycol. As a polyhydric alcohol having 3 or more valences,
Trimethylolpropane, trimethylolethane, glycerin, pentaerythritol and the like can be mentioned.

The dicarboxylic acid and the ester-forming dicarboxylic acid derivative for producing the polyester polyol or polyester carbonate polyol used in the present invention include aliphatic dicarboxylic acids or aromatic dicarboxylic acids having 4 to 12 carbon atoms. And derivatives thereof having the ability to form an ester are preferred. Examples of the aliphatic dicarboxylic acid include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid and the like. Examples of the aromatic dicarboxylic acid include phthalic acid, terephthalic acid, isophthalic acid and the like. These dicarboxylic acids may be used alone or in combination of two or more.

The carbonate compound used in the production of the polycarbonate polyol or polyester carbonate polyol used in the present invention is
Dialkyl carbonate, diaryl carbonate, alkylene carbonate and the like are preferable.

The polyester polyol used in the present invention is produced by a method similar to the known method used in the production of polyethylene terephthalate or polybutylene terephthalate, that is, transesterification or direct esterification followed by melt polycondensation reaction. It is possible.

The polycarbonate polyol used in the present invention can be produced by a method similar to the known method used for producing a polycarbonate from diphenyl carbonate and bisphenol A, that is, by a transesterification reaction.

The method for producing the polyester carbonate polyol used in the present invention is not particularly limited. For example,
A diol, a dicarboxylic acid, and a carbonate compound are charged at the same time, and a known production method, that is, an esterification or transesterification reaction can be performed. Alternatively, it is also possible to synthesize polyester polyol or polycarbonate polyol in advance, and then react with a carbonate compound in the former case, and react with a diol, dicarboxylic acid or the like in the latter case.

Further, the number average molecular weight of the polymer polyol used in the present invention is preferably in the range of 500 to 30,000, and when it is less than 500, the heat resistance and cold resistance of the obtained polyurethane are lowered, When it is more than 1,000, the mechanical performance of the obtained polyurethane is deteriorated. More preferably, it is in the range of 600 to 8,000. Further, the number of hydroxyl groups present in the high-molecular polyol varies depending on the use of the polyurethane finally obtained and cannot be said to be unequivocal, but is in the range of 2 or more, and particularly 2 to 4 per molecule. desirable.

Suitable organic polyisocyanates for use in the synthesis of polyurethanes in the present invention are aliphatic, cycloaliphatic or aromatic polyisocyanates, specifically 4,4'-diphenylmethane diisocyanate. Nart, p-
Molecular weight of phenylene diisocyanate, toluylene diisocyanate, 1,5-naphthylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dichlorohexyl methane diisocyanate, etc. 500 The following diisocyanates are exemplified. Preferably 4,4'-
They are diphenylmethane diisocyanate and toluylene diisocyanate.

In the present invention, if desired, a suitable chain extender may be used. As the chain extender, at least 2 hydrogen atoms capable of reacting with a chain growing agent commonly used in the polyurethane industry, that is, an isocyanate are used. A low molecular weight compound having a molecular weight of 400 or less, such as ethylene glycol, 1,4-butanediol, propylene glycol, 1,6-hexanediol, 1,4-bis (2-hydroxyethoxy) benzene, bis (β- Hydroxyethyl) terephthalate, xylylene glycol, glycerin, trimethylolpropane and other polyhydric alcohols; ethylenediamine, propylenediamine, isophoronediamine, hydrazine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodicyclohexylmethane, xylylenediamine Etc. Examples include amines. These compounds may be used alone or as a mixture of two or more kinds.

With respect to the method for producing the polyurethane of the present invention, a known urethanization reaction technique can be adopted. For example, after preheating the polymeric polyol or a mixture thereof with the above chain extender to about 40 to 100 ° C.,
By adding polyisocyanate in an amount such that the ratio of the number of active hydrogen atoms in these compounds to the isocyanate group is about 1: 1 and stirring vigorously for a short period of time, the mixture is allowed to stand at about 50 to 150 ° C. for polyurethane. Is obtained. It is also possible to employ a method of obtaining polyurethane via a urethane prepolymer. Polyisocyanate is usually used in a slight excess because it is usually affected by moisture.
These reactions can also be carried out in a solvent consisting of one or more of dimethylformamide, dimethylsulfoxide, dimethylacetamide, tetrahydrofuran, isopropanol, benzene, toluene, ethylcellosolve and the like. In this case, the solution concentration of polyurethane is 1
When it is carried out in the range of 0 to 50% by weight, it is convenient to obtain a polymer having a high molecular weight. Further, according to the research conducted by the present inventors,
In particular, when a thermoplastic polyurethane used as a molded product is obtained, it is preferable to qualitatively perform melt polymerization in the absence of an inert solvent, and it is particularly preferable that continuous melt polymerization using a multi-screw extruder is preferable. did. The temperature for melt polymerization is not particularly limited, but is preferably 200 ° C or higher and 260 ° C or lower. Keeping the temperature at 260 ° C. or lower increases the heat resistance, while keeping it at 200 ° C. or higher makes it possible to produce a thermoplastic polyurethane having excellent moldability.

The number average molecular weight of the resulting polyurethane is
Generally, it is preferably in the range of 5,000 to 500,000, more preferably in the range of 10,000 to 300,000. Further, the logarithmic viscosity (ηinh) of the polyurethane is generally preferably in the range of 0.1 to 2.0 dl / g, more preferably 0.4 to 2.0 dl / g.

Further, a suitable additive such as a colorant, a flame retardant, a lubricant, an ultraviolet absorber and a crystal nucleating agent may be added during or after the polymerization process.

Next, several examples of usage of the polyurethane obtained in the present invention will be described. 1. A substantially linear thermoplastic polyurethane pellet is prepared, which is heated and melted to produce an elastomer product by a method such as injection molding or calendering. 2. Polymer polyol, polyisocyanate and chain extender are mixed together, or the polymer polyol and polyisocyanate are reacted in advance to synthesize a prepolymer having a terminal isocyanate group or a terminal hydroxyl group,
This is mixed with a chain extender or polyisocyanate to prepare a cast elastomer product, or used for paints, adhesive inks and the like. 3. A polyurethane solution is obtained by dissolving polyurethane in a solvent or synthesizing polyurethane in a solvent,
It is used as a coating agent, impregnating agent, paint, adhesive, ink, or texture adjusting agent for synthetic leather, artificial leather, fibers and the like. 4. Dissolve the terminal isocyanate prepolymer in a solvent,
A stable spinning dope is prepared by adding a chain extender to this,
Elastic fibers are produced from this stock solution by a wet method or a dry method. 5. Various additives such as a foaming agent are mixed with the polymer polyol, and a prepolymer having a polyisocyanate or a terminal isocyanate group is added thereto, and the mixture is stirred at a high speed and foamed to produce a foam product.

The polyurethane of the present invention is specifically a sheet, film, tube, hose, roll, gear, packing material, anti-vibration material, belt, laminate product, automobile part, sports article, shoe sole, artificial leather, floor. Used for materials, paints, waterproofing agents, adhesives, inks, binders, heel tops, wire coatings, gaskets, industrial machine parts, elastic fibers, etc.

[0031]

The present invention will be specifically described with reference to the following examples. In the examples and comparative examples, the number average molecular weight of the polymer polyol and the logarithmic viscosity of the polyurethane are obtained according to the following methods. The strength, elongation, cold resistance and abrasion resistance of polyurethane were measured by the following methods.

Number average molecular weight: determined by hydroxyl value. -Logarithmic viscosity: Polyurethane was dissolved in dimethylformamide and measured at a concentration of 0.5 g / 100 ml at 30 ° C. -Strength / elongation: measured according to JIS K7311-1987. -Cold resistance: A dynamic viscoelasticity measuring device [Co., Ltd.] for a test piece made of a polyurethane film having a thickness of 100 μm
RVE, manufactured by Rheology Co., Ltd., was used to measure Tα (E ″ peak temperature, 11 Hz) by temperature dispersion and evaluate cold resistance. Wear resistance: Polyurethane film having a thickness of about 1 mm Using a Taber type abrasion tester (H-22, load 100
The state of the film after the abrasion test at 0 g, 2000 times) was judged by appearance. When there was almost no damage, it was marked with O, when it was serious, it was marked with X, and its middle was marked with Δ.

Reference Example 1 (Production of Polyester Diol) A mixture of norbornane-2,3-dimethanol and 1,6-hexanediol (molar ratio 15:85) 1610.
and adipic acid 1460 g (diol / adipic acid molar ratio = 1.3 / 1) are esterified while nitrogen gas is passed under normal pressure and condensed water is distilled off at a temperature of about 220 ° C. It was Acid value of polyester is 0.3m
When it became gKOH / g or less, the degree of vacuum was gradually increased by a vacuum pump to complete the reaction. Thus, a polyester diol having a hydroxyl value of 56.1 (PES-A) was obtained.

Reference Examples 2 to 6 PE shown in Table 1 was carried out in the same manner as in Reference Example 1 except that the diol and dicarboxylic acid components shown in Table 1 were used.
S-B to F were obtained.

Reference Example 7 (Production of Polycarbonate Diol) A mixture of norbornane-2,3-dimethanol and 1,6-hexanediol under a nitrogen stream (molar ratio 10: 9).
0) A mixture of 1462 g of diphenyl carbonate and 2140 g of diphenyl carbonate was heated, and phenol was distilled off from the reaction system at 200 ° C. The temperature is gradually raised to 210 to 220 ° C., most of the phenol is distilled off, and then vacuum is applied.
The remaining phenol was completely distilled off. As a result, a polycarbonate diol (PC-G) having a hydroxyl value of 56.1 (molecular weight of 2000) was obtained.

Reference Examples 8 to 10 PC-H to J shown in Table 1 were obtained in the same manner as in Reference Example 1 except that the diol component and the carbonate compound shown in Table 1 were used.

Reference Example 11 (Production of polyester carbonate diol) Norbornane-2,3-dimethanol 25 under a nitrogen stream.
A mixture of 4 g, 575 g of 1,6-hexanediol, 376 g of azelaic acid and 642 g of diphenyl carbonate (molar ratio of ester group to carbonate group 57:43) was heated, and phenol and water were distilled off from the reaction system at 160 ° C. did. When the acid value became 0.3 mgKOH / g or less, a vacuum was applied (2 to 10 mmHg) to proceed with condensation. As a result, the hydroxyl value was 56.1 and the molecular weight was 2000.
Polyester carbonate diol (PESC-K)
Got

Reference Examples 12 to 13 In the same manner as in Reference Example 1 except that the diol, dicarboxylic acid and carbonate compounds shown in Table 1 were used, respectively.
PESC-L to M shown in Table 1 were obtained.

[0039]

[Table 1]

The abbreviations used in Table 1 are shown below. A: norbornane-2,3-dimethanol B: norbornane-2,3-dicarboxylic acid C: perhydro-1,4: 5,8-dimethanonaphthalene-2,3-dimethanol D: perhydro-1,4: 5,8-Dimethanonaphthalene-2,3-dicarboxylic acid AD: adipic acid AZ: azelaic acid SB: sebacic acid DPC: diphenyl carbonate EC: ethylene carbonate BD: 1,4-butanediol HD: 1,6-hexanediol ND: 1,9-nonanediol MPD: 3-methyl-1,5-pentanediol NPG: neopentyl glycol PES: polyester diol PC: polycarbonate diol PESC: polyester carbonate diol

Example 1 The polyester diol produced in Reference Example 1 (PES-
A) In a mixed solution of 1 mol, 3 mol of 1,4-butanediol and dimethylformamide, under a nitrogen stream at 70 ° C.
Then, 4 mol of 4,4′-diphenylmethane diisocyanate was reacted, and after 5 hours, a 30 wt% polyurethane solution was obtained. The logarithmic viscosity of the obtained polyurethane is 0.9.
It was 6 dl / g. A film was prepared from the obtained polyurethane and various performances were examined. The results are shown in Table 2.

Examples 2 to 8 and Comparative Examples 1 to 5 Polyurethane solutions were obtained in the same manner as in Example 1 except that the polymer polyols shown in Table 1 were used instead of PES-A. Table 2 shows the results of examining various performances of the obtained polyurethane.

[0043]

[Table 2]

[0044]

As is clear from the above examples, the polyurethane of the present invention is excellent in cold resistance, abrasion resistance and mechanical performance.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Katsuzo Tanioku 1-1-9 Tsurumi, Tsurumi-ku, Osaka City, Osaka Prefecture Arakawa Chemical Industry Co., Ltd.

Claims (4)

[Claims] 1. A polyurethane having a main chain substantially formed of a polymeric polyol and an organic polyisocyanate, wherein the polymeric polyol has the following structural unit (I) in the molecule: (In the formula, X ₁ and X ₂ are each CH ₂ O— or C ₂
A polyurethane having a number average molecular weight of 500 to 30,000 and containing a group represented by OO-, and n represents 0 or 1. 2. The polyurethane according to claim 1, wherein the polymer polyol is at least one selected from polyester polyols, polycarbonate polyols and polyester carbonate polyols. 3. The following structural unit (I) in the molecule: (In the formula, X ₁ and X ₂ are each CH ₂ O— or C ₂
The method for producing polyurethane according to claim 1, wherein a polymer polyol having a group represented by OO- and n represents 0 or 1 is polymerized with an organic polyisocyanate. 4. The method for producing a polyurethane according to claim 3, wherein the polymerization reaction is carried out in the presence of a chain extender.