JPH06329751A - Composition for polyurethane - Google Patents

Abstract

PURPOSE:To provide the title composition which is lowly viscous and easily handleable and can give a cured polyurethane product excellent in water resistance and mechanical strengths. CONSTITUTION:The composition is prepared by mixing a polyester polyol prepared by esterifying a mixed diol comprising 70-45wt.% 1,9-nonanediol and 30-55wt.% 2-methyl-1,8-octanediol with a dicarboxylic acid component based on hydrogenated dimer, a diisocyanate compound and a chain extender.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for polyurethane which gives a polyurethane cured product having a low viscosity, excellent handling workability, and excellent mechanical strength and water resistance.

[0002]

2. Description of the Related Art Polyester polyols are generally used as a raw material for polyurethane resins, and the most versatile polyester polyol is adipic acid type polyester polyol. However,
The adipic acid-based polyester polyol has good mechanical properties and oil resistance, but has a problem of poor water resistance. A polyester polyol using dodecanedioic acid as a dicarboxylic acid has been proposed in order to improve water resistance, but dodecanedioic acid has not been generally used because it is expensive.

On the other hand, there is a proposal of a polyester polyol which uses hydrogenated dimer acid instead of dodecanedioic acid. As a polyester polyol which gives polyurethane excellent in water resistance, hydrogenated dimer acid and 1,4-cyclohexanedimethanol are used. A polyester polyol synthesized from such diols has been proposed (JP-A-4-145118).
Issue).

However, hydrogenated dimer acid and 1,4-
A polyester polyol synthesized from an alicyclic diol such as cyclohexanedimethanol has a problem that it has poor workability because it has a higher viscosity than a polyester polyol using an aliphatic diol. Polyester polyols composed of dimer acid have insufficient alkali resistance, and therefore, their suitability for use in paints and the like was not good enough.

[0005]

Means for Solving the Problems As a result of intensive studies for solving the above-mentioned problems, the present inventors have found that dicarboxylic acids containing hydrogenated dimer acid as a main component as dicarboxylic acids and 1,9- Nonanediol 70-45% by weight and 2-methyl-1,8-octanediol 30-55
It was found that polyester polyols obtained by polycondensing mixed diols each consisting of 1 wt% have low viscosity and a polyurethane cured product obtained by using them has extremely excellent water resistance and mechanical strength. The present invention has been completed.

That is, according to the present invention, a mixed diol composed of 70 to 45% by weight of 1,9-nonanediol and 30 to 55% by weight of 2-methyl-1,8-octanediol is mainly composed of hydrogenated dimer acid. It is a composition for polyurethane in which a polyester polyol obtained by esterification with a dicarboxylic acid, a diisocyanate compound and a chain extender are blended. Hereinafter, the present invention will be described in more detail.

The hydrogenated dimer acid in the present invention is a higher aliphatic dicarboxylic acid obtained by hydrogenating a dimer acid which is a dimer of an unsaturated aliphatic carboxylic acid having 18 carbon atoms. Representative unsaturated aliphatic carboxylic acids used as raw materials include oleic acid and linoleic acid. Dimer acid synthesized from oleic acid or linoleic acid is also commercially available from Henkel Hakusui Co., Ltd. and Emily Corporation of the United States. Therefore, hydrogenation of these commercially available dimer acids under high pressure gives water. An added dimer acid can be obtained. In addition, the product name PRIOL-1009 or P manufactured by Unichema International
Commercially available hydrogenated dimer acid such as RIPOL-1008 may be used. A preferred hydrogenated dimer acid has an acid value of 194.
~ 198, iodine value; 10 or less, saponification value; 196-2
00.

In the present invention, if desired, other dicarboxylic acids can be used together with the above hydrogenated dimer acid. Examples of such dicarboxylic acids include aliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid and dodecanedioic acid, Alternatively, aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid can be used. The amount of the dicarboxylic acid other than the hydrogenated dimer acid used is preferably 10 mol% or less of the total amount of the dicarboxylic acid component from the viewpoint of the water resistance of the obtained polyurethane. In order to obtain a polyurethane having excellent water resistance, it is desirable that all the acid components are hydrogenated dimer acid.

The polyester polyol according to the present invention contains 1,9-nonanediol (hereinafter referred to as ND) 70 to 70% of the dicarboxylic acid containing the hydrogenated dimer acid as a main component.
It is a polyester having hydroxyl groups at both ends of the molecule, which is obtained by polycondensation with a mixed diol consisting of 45% by weight and 30 to 55% by weight of 2-methyl-1,8-octanediol (hereinafter referred to as MOD). ND ratio is 7
When the mixed diol content exceeds 0% by weight, the resulting polyester diol is in a solid state and is poor in workability, and the polyurethane obtained from the polyester diol is inferior in tensile strength. On the other hand, when the proportion of ND is less than 45% by weight, the elongation percentage of the obtained polyurethane is too small. A more preferred mixed diol is a mixture of ND; 65-50% by weight and MOD; 35-50% by weight.

The polycondensation of the dicarboxylic acid containing hydrogenated dimer acid as a main component and the mixed diol is carried out in the same manner as in the case of producing a general polyester, that is, while removing the produced water out of the reaction system. It can be carried out by heating the raw material mixture to 220 to 250 ° C. in an inert gas and then removing water and excess diol under reduced pressure. The average molecular weight of the polyester diol preferred in the present invention is 1,000 to 2,000 in terms of polystyrene equivalent number average molecular weight by gel permeation chromatography.

The polyurethane composition of the present invention is a composition in which a compound such as a diisocyanate compound as a curing agent and a polyhydric alcohol or a polyvalent amine as a chain extender is blended with the above polyester diol. The following compounds may be mentioned as examples. For example, diphenylmethane diisocyanate, 2,
4-tolylene diisocyanate, 2,6-tolylene diisocyanate, phenylene diisocyanate, 1,5-
Aromatic diisocyanates such as naphthalene diisocyanate and xylylene diisocyanate, and aliphatic or alicyclic rings such as hexamethylene diisocyanate, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, hydrogenated xylylene diisocyanate, tetramethyl xylene diisocyanate Group diisocyanates and the like. Preferred are diphenylmethane diisocyanate, hexamethylene diisocyanate and isophorone diisocyanate.

As the polyhydric alcohol for the chain extender, ethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, 1,6-hexanediol,
1,9-nonane diol, 2-methyl-1,8-octane diol, 1,12-dodecane diol, dimer diol, trimethylol propane, glycerin and the like can be mentioned, and as the polyvalent amine, ethylene diamine, propylene diamine, Examples thereof include diethylenetriamine, piperazine, phenylenediamine, isophoronediamine, and tolylenediamine.

In the polyurethane composition of the present invention, each component is preferably used in a proportion of 1 to 4 mol of chain extender per 1 mol of the polyester polyol,
The amount of the diisocyanate compound used is preferably approximately equimolar to the total amount of the polyester polyol and the chain extender.

The polyurethane composition is prepared by mixing the polyester polyol and the diisocyanate compound in the total amount and then heating to about 50 to 100 ° C. to bond the isocyanate group to the end of the polyester polyol, and then the chain extender. A method of adding an aliphatic diol is preferable,
Alternatively, the polyester polyol, the diisocyanate and the chain extender may be mixed at the same time.

In the production of the above composition, an organic solvent may be used in combination, and preferable solvents include methyl ethyl ketone, ethyl acetate, toluene, dioxane, dimethylformamide and dimethyl sulfoxide.
When the composition for polyurethane of the present invention is used for applications such as polyurethane foam, it is preferable to use a composition containing no solvent.

The curing reaction of the polyurethane composition of the present invention is preferably carried out at room temperature to 200 ° C, more preferably 80 to 150 ° C. Upon curing, an amine-based catalyst such as triethylamine, N-ethylmorpholine, or triethylenediamine or a tin-based catalyst such as trimethyltin laurate or dibutyltin dilaurate may be used to accelerate the reaction. In addition, a colorant and various stabilizers for improving weather resistance and heat resistance may be added to the composition for polyurethane, if necessary.
It is preferably used for applications such as paints, adhesives, artificial leather, synthetic leather, fibers, foam and rubber.

[0017]

EXAMPLES The present invention will be explained more specifically by showing reference examples, examples and comparative examples. Reference Example 1 (Production of Polyester Polyol A) In a 1 L reactor,
Hydrogenated dimer acid [Unichema International Co., Ltd.
Manufactured by PRIPOL-1009) 290 g, and 1,9-
Mixed diol 400 in which the ratio of nonanediol and 2-methyl-1,8-octanediol is 65:35 (% by weight)
After charging g, the temperature was raised from room temperature to 240 ° C. over 1 hour under a nitrogen atmosphere, and then the reaction was carried out at 240 ° C. for 6 hours, and water generated during that time was distilled. Then, the excess diol was distilled off under a reduced pressure of 2 mmHg for 30 minutes to obtain a polyester polyol having the properties shown in Table 1.

Reference Example 2 (Production of Polyester Polyol B) As a mixed diol, a mixed diol in which the ratio of 1,9-nonanediol and 2-methyl-1,8-octanediol is 50:50 (% by weight) is used. A polyester polyol was obtained in the same manner as in Reference Example 1 except that the polyester polyol was used.

<Reference Examples 3 to 5> The hydrogenated dimer acid used in Reference Example 1 and 1,4-cyclohexanedimethanol (hereinafter referred to as CHDM), 1,9-nonanediol or 1,6-hexanediol (hereinafter HD) was used to synthesize a polyester polyol in the same manner as in Reference Example 1.

[0020]

[Table 1]

<Example 1> Polyester polyol A obtained in Reference Example 1; 150 g (0.14 mol) and diphenylmethane diisocyanate; 103.4 g (0.41 mol) were charged into a 500 ml flask and, under a nitrogen atmosphere, The reaction was carried out at 80 ° C for 2 hours. Then, 24.8 g (0.28 mol) of 1,4-butanediol as a chain extender was added and stirred for 30 seconds to obtain a uniform transparent polyurethane composition. A polyurethane cured product was obtained by heating the obtained composition at 100 ° C. for 24 hours. By subjecting the cured product to hot pressing at a temperature of 180 ° C.,
A dumbbell test piece was prepared, and its tensile strength and elongation at break were measured (according to JIS K7113). For the purpose of the water resistance test, the tensile strength and the elongation of the dumbbell after being immersed in boiling water for 1 week were also measured. The results are shown in Table 2.
It is as follows.

<Comparative Examples 1 to 3> Polyurethane cured products were obtained in the same manner as in Example 1 using the polyester polyols obtained from the diols outside the scope of the present invention obtained in Reference Examples 3 to 5. Comparative example 1 using polyester polyol C
Then, even if the surface was cured, only a cured product with an uncured interior was obtained, so the physical properties of the cured product of the same example could not be measured. The results of the other examples are as shown in Table 2.

[0023]

[Table 2]

Example 2 A polyurethane cured product was obtained in the same manner as in Example 1 except that the polyester polyol B was used and hexamethylene diisocyanate was used as the diisocyanate, and the physical properties thereof were measured. The results are shown in Table 3.

Comparative Examples 4 to 5 Polyurethane cured products were obtained using polyester polyol C or polyester polyol E in the same manner as in Example 2.

[0026]

[Table 3]

[0027]

EFFECT OF THE INVENTION The composition for polyurethane of the present invention has a low viscosity and excellent workability and can be handled without solvent. Moreover, according to the composition, a polyurethane cured product having excellent mechanical strength and water resistance can be obtained.

Claims (1)

[Claims] 1. 70-45% by weight of 1,9-nonanediol and 30-55 of 2-methyl-1,8-octanediol
A composition for polyurethane containing a polyester polyol, a diisocyanate compound and a chain extender, which are obtained by esterifying a mixed diol (weight%) with a dicarboxylic acid containing hydrogenated dimer acid as a main component.