JPH11166041A - Production of polyurethane foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for the production of a polyurethane foam having a low density, good appearance and feeling and excellent mechanical strengths such as tensile strength and tear strength. SOLUTION: This process for the production of a polyurethane foam comprises the reaction and foaming of a polyester polyol; polyisocyanate component with a polyol component containing a polyester polyol. The polyolpolyisocyanate component is obtained by the condensation polymerization of an acid component containing a phthalic acid component consisting of phthalic anhydride and/or o-phthalic acid and an aliphatic polybasic acid with a pal-yhydric alcohol, exhibits liquid state at 40 deg.C and has a viscosity of $10,000 mPa.s at 60 deg.C. The isocyanate prepolymer is produced from a polyisocyanate component and a polyol component containing a polyester polyol. The polyurethane foam is produced by reacting and foaming an isocyanate prepolymer with a polyol component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing a polyurethane foam. More specifically, it relates to a method for producing a polyurethane foam, a method for producing an isocyanate prepolymer, which has high mechanical strength and is suitably used as shoe soles and the like, and a polyester polyol used as a raw material of the polyurethane foam.

[0002]

2. Description of the Related Art In the production of a molded article of polyurethane foam, the lower the density of the polyurethane foam, the lower the cost. Therefore, the lower the density, the lower the resin amount per unit volume. Decrease.

Therefore, it has been proposed to add a crosslinking agent, a polyfunctional polyol, an aromatic polyol or the like to the polyol in order to improve the mechanical strength of the molded article.

However, when a crosslinking agent or a polyfunctional polyol is used in preparing an isocyanate prepolymer, there is a problem that gelation is caused. When an aromatic polyol is used, the viscosity and melting point of the aromatic polyol are extremely high. Therefore, when producing a polyurethane foam from a prepolymer obtained using the aromatic polyol, the polyurethane polyol is used. There is a problem that it is difficult to adjust the viscosity and the melting point of the prepolymer suitable for the production conditions of the foam.

[0005]

SUMMARY OF THE INVENTION The present invention provides a low density,
An object of the present invention is to provide a method for producing a polyurethane foam having a good appearance and feeling and excellent mechanical strength such as tensile strength and tear strength.

[0006]

That is, the gist of the present invention is as follows.
(1) An acid component containing (A) at least one phthalic acid component selected from phthalic anhydride and o-phthalic acid, and an aliphatic polybasic acid, and (B) a polyhydric alcohol. Polyester polyol which has been polycondensed, exhibits a liquid state at 40 ° C., and has a viscosity at 60 ° C. of 10,000 mPas or less,
(2) a method for producing a polyurethane foam in which a polyisocyanate component and a polyol component containing the polyester polyol described in (1) are reacted and foamed, (3)
The polyol component used for producing the isocyanate prepolymer prepared from the polyisocyanate component and the polyol component is (A) phthalic anhydride and o-
An acid component containing at least one phthalic acid component selected from phthalic acid, an aliphatic polybasic acid, and (B) a polyhydric alcohol are subjected to polycondensation to form a liquid at 40 ° C. ,And
A method for producing an isocyanate prepolymer containing a polyester polyol having a viscosity at 60 ° C. of 10,000 mPa · s or less, and (4) an isocyanate prepolymer obtained by the production method according to the above (3); And a method for producing a polyurethane foam.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester polyol of the present invention is useful as a raw material for producing a polyurethane foam.

The polyester polyol of the present invention comprises
(A) Polycondensation of an acid component containing at least one phthalic acid component selected from phthalic anhydride and o-phthalic acid and an aliphatic polybasic acid, and (B) a polyhydric alcohol. Thus, it is obtained.

As the phthalic acid component, one or more selected from phthalic anhydride and o-phthalic acid are used. Therefore, phthalic anhydride and o-phthalic acid may be used alone or in combination.

Examples of the aliphatic polybasic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, nonamethylene dicarboxylic acid, decamethylene dicarboxylic acid,
Undecamethylene dicarboxylic acid, dodecamethylene dicarboxylic acid, tridecamethylene dicarboxylic acid, tetradecamethylene dicarboxylic acid, pentadecamethylene dicarboxylic acid, hexadecamethylene dicarboxylic acid, heptadecamethylene dicarboxylic acid, octadecamethylene dicarboxylic acid,
Nonadecamethylene dicarboxylic acid, icosamethylene dicarboxylic acid, henicosamethylene dicarboxylic acid, docosamethylene dicarboxylic acid, tetracosamethylene dicarboxylic acid,
Saturated aliphatic dicarboxylic acids such as octacosamethylene dicarboxylic acid and dotriacontamethylene dicarboxylic acid are exemplified, and these aliphatic polybasic acids can be used alone or in combination of two or more. Among these, adipic acid is used in the resulting polyurethane foam,
From the viewpoint of imparting excellent hydrolysis resistance and tensile strength in a well-balanced manner, high safety and low cost, it can be suitably used.

As described above, the acid component used in the present invention contains a phthalic acid component and an aliphatic polybasic acid. Here, “containing” means that the acid component is a phthalic acid component. And an aliphatic polybasic acid, in addition to the phthalic acid component and the aliphatic polybasic acid in the acid component, other acid components in an amount that does not inhibit the object of the present invention. It means that it may be included. Examples of such other acid components include unsaturated aliphatic dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid; halogen-containing dicarboxylic acids such as tetrabromophthalic acid;

[0012]

Embedded image

Wherein R ¹ is an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 12 carbon atoms, an arylalkyl group having 7 to 13 carbon atoms, a halogen atom, an alkoxy group having 1 to 4 carbon atoms, A hydroxyl group or a carbon number 6 which may have a substituent
To 12 aryloxy groups], terephthalic acid, isophthalic acid, a general formula:

[0014]

Embedded image

[Wherein R ² is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 12 carbon atoms, and 7 to 13 carbon atoms.
An arylalkyl group, a halogen atom, an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, or an aryloxy group having 6 to 12 carbon atoms which may have a substituent]. However, the present invention is not limited only to such an example.

The amount of the other acid component is preferably 10% by weight.
The content is more preferably 5% by weight or less, and the acid component is particularly preferably composed of a phthalic acid component and an aliphatic polybasic acid.

In the acid component, the molar ratio of phthalic acid component / aliphatic polybasic acid is 0.05 or more so as not to increase the freezing point and to give a liquid under molding conditions (molding temperature: about 40 ° C.). It is preferably at least 0.08, and from the viewpoint of facilitating injection and injection at the time of molding, it is desirably at most 0.2, preferably at most 0.15. When the polyester polyol is used as the polyol component when producing a polyurethane foam, the molar ratio of phthalic acid component / aliphatic polybasic acid is 0.15
Or less, preferably 0.12 or less.

Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-propanediol, 1,4-butanediol,
1,5-pentanediol, neopentyl glycol, 1,6-
Hexane diol, 1,7-heptane diol, 1,8-octane diol, 1,9-nonane diol, 1,10-decane diol and the like, and these polyhydric alcohols may be used alone or in combination of two or more. They can be used in combination. Among them, ethylene glycol and / or 1,4-butanediol can be suitably used from the viewpoint of obtaining a polyurethane foam having physical properties such as excellent tensile strength. Ethylene glycol and 1,4-butanediol may be used alone or in combination.

The polyester polyol of the present invention can be obtained by polycondensing an acid component with a polyhydric alcohol.

Regarding the ratio between the acid component and the polyhydric alcohol, the reaction between the acid component and the polyhydric alcohol is a polycondensation reaction, and both ends are always hydroxyl groups. It is preferable that the equivalent ratio [COOH / OH] of the COOH group of the polyhydric alcohol to the OH group of the polyhydric alcohol is slightly smaller than 1.

As a method of polycondensing an acid component and a polyhydric alcohol, for example, a method such as Guenter
Oertel) Hen "Polyurethane Handbook" Hanser,
The method is not particularly limited, as long as it is a method employed in producing a conventional polyester as described in the second edition (1994), pp. 65-72.

The polyester polyol obtained by polycondensing an acid component and a polyhydric alcohol is heated at 40 ° C.
And a liquid having a viscosity at 60 ° C. of 10,000 mPa · s or less is used.

The reason why the polyester polyol is liquid at 40 ° C. is used because the control temperature of the raw material tank and the raw material circulation in the generally used automatic mixing injection foaming machine is around 40 ° C. Here, “presenting a liquid at 40 ° C.” means exhibiting fluidity at 40 ° C., and the viscosity of the polyester polyol is
Indicates that it is less than 20000 mPa · s at 40 ° C.

The viscosity of the polyester polyol at 60 ° C. is not more than 10,000 mPa · s, preferably 3000 mPa · s.
s or less is to improve the injection moldability when molding the polyurethane foam and to perform stable ejection.

The viscosity is measured by a Brookfield viscometer, a type of rotational viscometer, after the measurement system is stabilized.

In consideration of the viscosity, melting point and the like of the polyester polyol, the number average molecular weight of the polyester polyol is 500 to 4000, preferably 500 to 3500, more preferably 500 to 3000, and particularly preferably 1000 to 2500. Is desirable.

The polyester polyol thus obtained can be suitably used as a raw material for a polyurethane foam.

The method for producing a polyurethane foam of the present invention has a great feature in that a specific polyester polyol is used. As described above, in the present invention, by using the specific polyester polyol, the obtained polyurethane foam has excellent mechanical strength.

Further, an isocyanate prepolymer can be prepared using the polyester polyol,
The isocyanate prepolymer can be suitably used for producing a polyurethane foam as described later.

The method for producing the polyurethane foam of the present invention using the polyester polyol mainly includes:
(1) When a polyisocyanate component and a polyol component are reacted and foamed to produce a polyurethane foam,
A method of using the polyester polyol as a polyol component (hereinafter referred to as Production Method I); and (2) reacting and foaming an isocyanate prepolymer prepared from a polyisocyanate component and a polyol component with a polyol component. When a polyurethane foam is produced by the above method, there is a method (hereinafter referred to as production method II) in which a polyol containing the polyester polyol is used as a polyol component used in preparing an isocyanate prepolymer.

First, the manufacturing method I will be described.

In the production method I, the one containing the polyester polyol is used as the polyol component used when the polyisocyanate component and the polyol component are reacted and foamed.

The following polyols can be contained in the polyol component. Such polyols include:
For example, ethylene glycol, diethylene glycol,
One or more of propylene glycol, 1,4-butanediol, 1,5-pentanediol, methylpentanediol, 1,6-hexanediol, trimethylolpropane, glycerin, pentaerythritol, diglycerin, dextrose, and sorbitol; Polyester polyol, polypropylene glycol, polyoxytetramethylene glycol obtained by polycondensing a polyhydric alcohol with one or more dibasic acids such as oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, and dimer acid And the like. Polyether polyols, polycaprolactone polyols, polycarbonate polyols and the like can be mentioned, and these can be used alone or in combination of two or more.

The content of the polyester polyol in the polyol component is from 10 to 95% by weight, preferably from 10 to 95% by weight, from the viewpoint of maintaining a suitable liquid state and viscosity of the polyol component and producing a polyurethane foam having excellent mechanical strength.
It is desirable that the content be 20 to 90% by weight, more preferably 40 to 90% by weight.

In addition, the polyol component may include
For example, chain extenders, foaming agents, urethanization catalysts, foam stabilizers,
Stabilizers, pigments, and the like may be appropriately added in appropriate amounts.

As the chain extender, low molecular weight and 2
Compounds having more than one active hydrogen can be used. Representative examples of chain extenders include ethylene glycol,
Polyhydric alcohols such as diethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, methylpentanediol, 1,6-hexanediol, trimethylolpropane, glycerin, pentaerythritol, diglycerin, dextrose, and sorbitol And aliphatic polyamines such as ethylenediamine and hexamethylenediamine, alkanolamines such as diethanolamine, triethanolamine and diisopropanolamine. These can be used alone or in combination of two or more.

Examples of the foaming agent include water, fluorocarbons, and the like.
A mixture of more than one species can be used.

Examples of urethanization catalysts include tertiary amines such as triethylenediamine, N, N, N ', N'-tetramethylhexamethylenediamine, 1,2-dimethylimidazole, tin (II) octoate, Tin compounds such as dibutyltin dilaurate and the like can be mentioned, and these can be used alone or in combination of two or more.

Examples of foam stabilizers include silicone surfactants such as dimethylpolysiloxane, polyoxyalkylene polyol-modified dimethylpolysiloxane, and alkylene glycol-modified dimethylpolysiloxane, fatty acid salts, sulfate salts, phosphate salts, and sulfones. Examples include anionic surfactants such as acid salts, and these can be used alone or in combination of two or more.

As the stabilizer, for example, dibutylhydroxytoluene, pentaerythrityl-tetrakis [3- (3,
Hindered phenol radical scavengers such as 5-di-t-butyl-4-hydroxyphenyl) propionate] and isooctyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate; phosphorous acid, Antioxidants such as phosphites such as triphenylphosphite, triethylphosphite and triphenylphosphine; 2- (5-methyl-2
-Hydroxyphenyl) benzotriazole, methyl-3
-[3-t-butyl-5- (2H-benzotriazol-2-yl) -4-
[Hydroxyphenyl] UV absorbers such as condensates of propionate and polyethylene glycol, and the like, and these can be used alone or in combination of two or more.

Examples of the pigment include inorganic pigments represented by transition metal salts, organic pigments represented by azo compounds, and carbon powder. These pigments may be used alone or in combination of two or more. Can be used.

Since the polyol component is liquid at room temperature and can be injected even at a low pressure, a polyurethane foam can be molded without any problem by reacting with a polyisocyanate component described later.

Typical examples of the polyisocyanate component used in the production method I include an isocyanate prepolymer.

The isocyanate prepolymer is obtained by stirring and reacting a polyisocyanate monomer and a polyol in the presence of an excess of a polyisocyanate monomer by a conventional method.

Specific examples of the polyisocyanate monomer include tolylene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and polymethylene polyphenyl diisocyanate. , 3,3'-dimethyl-4,4'-biphenylene diisocyanate, 3,3'-dimethyl-4,4'-diphenylmethane diisocyanate, 3,3'-dichloro-4,4'-biphenylene diisocyanate, 1,5- Examples thereof include polyisocyanate compounds such as naphthalene diisocyanate, and modified products thereof, for example, carbodiimide modified products, and these can be used alone or in combination of two or more. Of these, 4,4'-diphenylmethane diisocyanate alone or in combination with 4,4'-diphenylmethane diisocyanate and a carbodiimide modified product thereof is particularly preferred in the present invention.

Examples of the polyol include ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, methylpentanediol, 1,6-hexanediol, trimethylolpropane, glycerin, pentaerythritol ,
Obtained by polycondensing one or more polyhydric alcohols such as diglycerin, dextrose and sorbitol with one or more dibasic acids such as oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid and dimer acid. Polyether polyols such as polyester polyol, polypropylene glycol, polyoxytetramethylene glycol, etc., polycaprolactone polyols, polycarbonate polyols, etc., which can be used alone or as a mixture of two or more.

In preparing the isocyanate prepolymer, additives may be added as necessary.

The additives include, for example, additives used as needed when preparing a polyester polyol, and acid gases such as hydrogen chloride gas and sulfur dioxide gas in order to prevent the isocyanate prepolymer from self-polymerizing. Isocyanate self-polymerization inhibitors such as acid chlorides such as acetyl chloride, benzoyl chloride and isophthalic chloride; and phosphoric compounds such as phosphoric acid, monoethyl phosphate and diethyl phosphate can be used. These additives can be used alone or in combination of two or more.

The NCO% of the isocyanate prepolymer is
In order to prevent the viscosity from becoming too high to make molding with a low-pressure foaming machine difficult, it is desirable that the viscosity be 15% or more, preferably 17% or more. In order to avoid this, it is desirable that the content be 25% or less, preferably 23% or less, particularly preferably 22% or less.

The isocyanate prepolymer is liquid at 15 ° C. or higher and can be discharged even at a low pressure, so that it can be used for producing a polyurethane foam at a molding temperature of 40 to 50 ° C. without any problem.

In the production method I, when reacting the polyisocyanate component and the polyol component, it is preferable that the ratio between the two is adjusted so that the isocyanate index becomes 95 to 105.

In the production method I, the polyisocyanate component and the polyol component are mixed and stirred by a molding machine.
By injecting into a molding die and foaming, a polyurethane foam can be molded. More specifically, for example, after adjusting the temperature of the polyol component to about 40 ° C. using a tank or the like, and then using a foaming machine such as an automatic mixing injection type foaming machine and an automatic mixing injection foaming machine, the polyisocyanate component is used. By reacting with the above, a polyurethane foam can be molded.

According to the production method I, after mixing the polyisocyanate component and the polyol component, the mixture is usually mixed with the polyisocyanate component at 40 to 50%.
It can be formed into urethane shoe soles by a foaming machine adjusted to about ° C.

The production method I can be employed for the production of non-foamed elastomers. However, when it is used for producing shoe soles, the resulting polyurethane foam has a resin content per unit volume. Despite the decrease, mechanical strength such as tensile strength and tear strength can be sufficiently improved.

Next, the production method II will be described.

In the production method II, when the isocyanate prepolymer prepared from the polyisocyanate component and the polyol component is reacted with the polyol component and foamed to produce a polyurethane foam, the polyol component used in the isocyanate prepolymer is used. , (A) an acid component containing at least one phthalic acid component selected from phthalic anhydride and o-phthalic acid, and an aliphatic polybasic acid, and (B) a polyhydric alcohol. I got it,
It is liquid at 40 ° C and has a viscosity of 10,000 mPa
s A polyester polyol containing the following polyester polyol is used.

When used in the preparation of the isocyanate prepolymer, the phthalic acid component / aliphatic polybasic acid molar ratio is 0.55 or less, preferably 0.3 or less, more preferably from the viewpoint of easy handling of the isocyanate prepolymer. Is desirably 0.2 or less, and desirably 0.05 or more, preferably 0.08 or more.

The polyisocyanate component which is a raw material for producing the isocyanate prepolymer includes, for example, the polyisocyanate monomer used in the production method I.

Specific examples of the polyisocyanate monomer are the same as the specific examples of the polyisocyanate monomer used in Production method I. Among these examples, it is particularly preferable to use 4,4′-diphenylmethane diisocyanate alone or to use 4,4′-diphenylmethane diisocyanate in combination with a carbodiimide modified product thereof.

As the polyol component which is a raw material for producing the isocyanate prepolymer, one containing a polyester polyol is used.

In the production method II, since the viscosity of the obtained isocyanate prepolymer can be suitably maintained by using the polyester polyol, excellent mechanical strength can be imparted to the polyurethane foam.

Here, "containing polyester polyol" means not only that the polyester polyol is used, but also that other polyol components are contained in addition to the polyester polyol. .

As the polyol component, for example, the production method I
The same ones as those used in the above are exemplified.

The content of the polyester polyol in the polyol component is 10 to 100% by weight, preferably 50 to 100% by weight.
Desirably, it is 100% by weight.

The ratio between the polyisocyanate component and the polyol component is such that the equivalent ratio of NCO group / OH group is usually 5%.
It is desirable to adjust so as to be about 30.

In preparing the isocyanate prepolymer, additives such as a self-polymerization inhibitor, an antioxidant, and an ultraviolet absorber may be added as necessary.

Examples of the self-polymerization inhibitor include the same self-polymerization inhibitors that can be added when preparing the isocyanate prepolymer in Production Method I.

As the antioxidant and the ultraviolet absorber, those which can be added to the polyol component used in the production method I are exemplified.

Next, an isocyanate prepolymer is obtained by stirring and reacting the polyisocyanate component, the polyol component and, if necessary, additives in a conventional manner.

The NCO% of the thus obtained isocyanate prepolymer is desirably 12% or more, preferably 14% or more, in order to prevent the viscosity from increasing so that molding with a low-pressure foaming machine becomes difficult. Also, in order to avoid lowering the viscosity and lowering the measuring accuracy of the foaming machine,
It is desirable that the content be 25% or less, preferably 23% or less, and particularly preferably 22% or less.

The isocyanate prepolymer is liquid at 15 ° C. or higher and can be discharged even at a low pressure, so that it can be used for producing a polyurethane foam without any problem even at a molding temperature of 40 to 50 ° C., for example.

Next, a polyurethane foam is obtained by reacting and foaming the isocyanate prepolymer and the polyol component.

Examples of the polyol component used for the reaction with the isocyanate prepolymer include the same polyols other than the polyester polyol used for the polyol component in Production Method I.

The polyol component used for the reaction with the isocyanate prepolymer may optionally contain a chain extender, a foaming agent, a urethanization catalyst, a stabilizer, a pigment, and the like in appropriate amounts. Examples of these components are the same as those that can be added to the polyol component used in Production Method I.

In the production method II, when reacting the polyisocyanate component and the polyol component, it is preferable to adjust the ratio between the two so that the isocyanate index becomes 95 to 105.

In the production method II, a polyurethane foam can be molded by mixing, stirring, injecting into a molding die, and foaming an isocyanate prepolymer, a polyol component and, if necessary, an additive. More specifically, for example, the temperature of the polyol component is usually adjusted to about 40 ° C. using a tank or the like, and then the isocyanate prepolymer is heated using a foaming machine such as an automatic mixing injection type foaming machine and an automatic mixing injection foaming machine. By reacting with
Polyurethane foam can be molded.

According to Production Method II, after mixing the isocyanate prepolymer and the polyol component,
It can be formed into urethane shoe soles by a foaming machine adjusted to about 50 ° C.

The production method II can be used for the production of a non-foamed elastomer. However, when the production method II is used for the production of shoe soles, the resulting polyurethane foam has a reduced resin content per unit volume. Nevertheless, mechanical strength such as tensile strength and tear strength can be sufficiently improved.

Thus, the density of the molded body of the polyurethane foam obtained by the production method I or the production method II is preferably from the viewpoint of obtaining sufficient mechanical strength and reducing the density.
It is practical that the amount is 15 to 1.0 g / cm ³ , preferably 0.2 to 0.6 g / cm ³ , more preferably 0.2 to 0.4 g / cm ³ .

[0080]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, "parts" means "parts by weight".

Preparation Examples 1 to 3 (Polyester polyol A
In a four-necked flask, 100 parts of adipic acid, phthalic acid component (phthalic anhydride or o-phthalic acid) and glycol (ethylene glycol or 1,4-butanediol) in the amounts shown in Table 1 were added. After the charging, a stirring rod, a dehydrating tube, a nitrogen gas introducing tube and a thermometer were attached to the flask.

Next, nitrogen gas was introduced into the flask, and the generated water was distilled off, and the temperature was raised to 220 ° C.

After confirming that the inside of the flask became transparent, the pressure was gradually reduced, and water was further distilled off.

The reaction was continued until the acid value of the reaction solution became 1 KOH mg / g or less, and polyester polyols A to C which were liquid at 40 ° C. were obtained.

As the physical properties of the obtained polyester polyols A to C, an acid value, a hydroxyl value, a viscosity, a freezing point and a number average molecular weight were examined. Table 1 shows the results.

The acid value is JIS K 0070 and the hydroxyl value is J
IS K 0070, viscosity was measured in accordance with JIS Z 8803 (using a Brookfield viscometer, type B), and freezing point was measured in accordance with JIS K 0065. The number average molecular weight was calculated from the hydroxyl value.

[0087]

[Table 1]

Production Examples 1 to 3 (Production of polyol components A to C) 40 parts of polyester polyol A, B or C obtained in Preparation Example 1, 2 or 3 shown in Table 2, polyester polyol [starting monomer: ethylene glycol, 1,4-butanediol and adipic acid, ethylene glycol / 1,4-butanediol (weight ratio) = 1/1, number average molecular weight: 1300] 60
Parts, 11 parts of ethylene glycol as a chain extender, 1.05 parts of water as a foaming agent, 0.8 parts of triethylenediamine and 1 part of a silicone foam stabilizer as a catalyst, and the mixture was adjusted to 60 ° C.
By stirring, polyol components A to C were obtained.

As physical properties of the obtained polyol components A to C, an acid value, a hydroxyl value and a viscosity were examined in the same manner as in Preparation Example 1, and a water content was examined according to JIS K0068. Table 2 shows the results.

Production Example 4 (Production of Polyol Component D) 40 parts of polyester polyol (polyethylene-1,4-butanediol adipate, number average molecular weight: 2200), polyester polyol (polyethylene-1,4-butanediol adipate, number average) Molecular weight: 1300) 60 parts, 11 parts of ethylene glycol as a chain extender, 1.05 parts of water as a foaming agent, 0.8 parts of triethylenediamine as a catalyst and 1 part of a silicone foam stabilizer, temperature-controlled to 60 ° C., and stirring, A polyol component D was obtained.

The physical properties of the obtained polyol component D were examined in the same manner as in Production Example 1. Table 2 shows the results.

[0092]

[Table 2]

Examples 1 to 3 Polyol components A to C obtained in Production Examples 1 to 3 and an isocyanate prepolymer (trade name: Eddy Form B-2009, manufactured by Kao Corporation, NCO%: 18.5%) The automatic mixing type injection foaming machine (manufactured by Polyurethane Engineering, model MU
-203S, Model No. 6-018) and foamed under the following molding conditions to produce a polyurethane foam sheet of 10 mm × 100 mm × 300 mm. Table 3 shows the polyol components used in each example.

[Molding conditions] Isocyanate index: 100 to 103 Mixing temperature: The temperature of both the isocyanate prepolymer and the polyol component was adjusted to 35 to 45 ° C.

Reactivity: Cream time 5 to 10 seconds Silk time 15 to 25 seconds Rise time 35 to 60 seconds Tack free time 30 to 55 seconds Demold time 4.5 to 5.5 minutes Mold: Mold temperature 45 to 55 ° C Release agent silicone and wax density: free foam density 0.12~0.32g / cm ³ green density 0.35 g / cm ³ ripening conditions: 1 week at ambient temperature Next, as the physical properties of the resulting sheet hardness, tensile strength (tensile strength), The tear strength and elongation at break were measured according to the following methods. Table 3 shows the results.

[Physical Properties of Sheet] Hardness (Asker C): Measured in accordance with SRIS 0101 Tensile strength: Measured in accordance with JIS K 6301 using JIS No. 1 dumbbell Tear strength: Measured in accordance with JIS K 7311 Elongation at break: Measured using JIS No. 1 dumbbell in accordance with JIS K 6301

Comparative Example 1 In Example 1, as the polyol component and the isocyanate prepolymer, the polyol component D obtained in Production Example 4 and an isocyanate prepolymer (manufactured by Kao Corporation)
(Eddie Form B-2009; NCO%: 18.5%), except that a polyurethane foam sheet was prepared in the same manner as in Example 1.

The physical properties of the obtained polyurethane foam sheet were examined in the same manner as in Example 1. Table 3 shows the results.

[0099]

[Table 3]

From the results shown in Table 3, it can be seen that the polyurethane foam sheets obtained in Examples 1 to 3 had the same density as the polyurethane foam sheet obtained in Comparative Example 1 while having the same density. It can be seen that the tensile strength is remarkably excellent.

Preparation Examples 4 to 7 (Polyester polyol D
Preparation of G) In a four-necked flask, 100 parts of adipic acid, phthalic anhydride and ethylene glycol in the amounts shown in Table 4 were charged and reacted in the same manner as in Preparation Examples 1 to 3 to obtain polyester polyol D.
~ G was obtained. The physical properties of the obtained polyester polyols D to G were examined in the same manner as in Preparation Examples 1 to 3. Table 4 shows the results.

[0102]

[Table 4]

Production Examples 5 to 9 (Production of Isocyanate Prepolymers A to E) A flask was charged with 100 parts of 4,4′-diphenylmethane diisocyanate, the temperature was adjusted to 60 ° C., and the mixture was stirred and stirred in a nitrogen stream. The polyester polyols A to E obtained in Preparation Examples 1 to 5 in the amounts shown in Table 5 were gradually added dropwise at 40 ° C, and the reaction was carried out for 2 hours while maintaining the temperature in the flask at 50 to 70 ° C.

Next, the carbodiimide-modified MDI (manufactured by Nippon Polyurethane Co., Ltd., trade name: Coronate MX) in the amount shown in Table 5 was added to the flask, and the mixture was aged for 1 hour. Isocyanate prepolymers A to E having a viscosity at 60 ° C. were obtained.

[0105]

[Table 5]

Production Example 10 (Isocyanate prepolymer F
Production of Polyester Polyol F obtained in Preparation Example 6 had a high freezing point and was difficult to drop at 40 ° C., so that it was not easy to produce a prepolymer.

Production Example 11 (Production of Isocyanate Prepolymer G) Since the polyester polyol G obtained in Preparation Example 7 has a high freezing point and cannot be dropped at 40 ° C.,
Polyester polyols A to E obtained in Preparation Examples 1 to 5
And could not be handled in the same way. Therefore, it was not easy to produce a prepolymer using the polyester polyol G obtained in Preparation Example 7.

Examples 4 to 8 and Comparative Example 2 Polyester polyol [Starting monomers: ethylene glycol, diethylene glycol and adipic acid, ethylene glycol / diethylene glycol (weight ratio) = 1/1]
, Number average molecular weight: 2200] 100 parts, ethylene glycol 1
One part, water 1.05 part, triethylenediamine 0.8 part and silicone foam stabilizer 1 part were added and mixed to obtain a polyol component.

Next, the obtained polyol component was mixed with the isocyanate prepolymers A to E or isocyanate prepolymers (manufactured by Kao Corporation, trade name: Eddy Form B-2009, NCO%) obtained in Production Examples 5 to 9. : 18.5%) to produce a polyurethane foam sheet in the same manner as in Examples 1 to 3.

The properties of the obtained polyurethane foam sheet were examined in the same manner as in Examples 1 to 3. Table 6 shows the results.
Shown in

Examples 9 to 13 and Comparative Example 3 Polyester polyol [starting monomers: ethylene glycol, 1,4-butanediol and adipic acid, ethylene glycol / 1,4-butanediol (weight ratio) = 1 / 0.65,
Number average molecular weight: 2200] 60 parts and polyester polyol [raw material monomers: ethylene glycol, 1,4-butanediol and adipic acid, ethylene glycol / 1,4-butanediol (weight ratio) = 1/1, number average molecular weight: 1300) 40
Parts, 11 parts of ethylene glycol, 1.65 parts of water, 0.8 parts of triethylenediamine and 1 part of a silicone foam stabilizer were added and mixed to obtain a polyol component for forming a foam.

Next, the obtained polyol component was mixed with the isocyanate prepolymers A to E or isocyanate prepolymers (manufactured by Kao Corporation, trade name: Ediform B-2009, NCO%) obtained in Production Examples 5 to 9. : 18.5%) to produce a polyurethane foam sheet in the same manner as in Examples 1 to 3.

The physical properties of the obtained polyurethane foam sheet were examined in the same manner as in Examples 1 to 3. Table 6 shows the results.
Shown in

[0114]

[Table 6]

From the results shown in Table 6, the polyurethane foam sheets obtained in Examples 4 to 13 were compared with Comparative Examples 2 to 3.
It can be seen that the tensile strength is remarkably excellent while the density of the molded article is almost the same as compared with the polyurethane foam sheet obtained in the above.

[0116]

According to the production method of the present invention, especially in the molding of polyurethane foam such as polyurethane shoe soles, even if the density is low, the physical properties such as the tensile strength and the like are maintained without impairing the appearance and feeling. Significantly improved polyurethane foams can be produced.

Further, according to the production method of the present invention, the initial strength of the polyurethane foam is remarkably excellent, so that the productivity of the polyurethane foam is extremely high.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 75:04 (72) Inventor Kazunari Takemura 1334 Minato, Wakayama-shi Kao Corporation Research Institute (72) Inventor Masahiro Mori Wakayama-shi 1334 Minato Kao Research Institute

Claims (6)

[Claims] 1. An acid component comprising (A) at least one phthalic acid component selected from phthalic anhydride and o-phthalic acid, and an aliphatic polybasic acid, and (B) a polyhydric alcohol. A polyester polyol having a liquid state at 40 ° C. and a viscosity at 60 ° C. of 10,000 mPa · s or less. 2. The polyester polyol according to claim 1, wherein the molar ratio of phthalic acid component / aliphatic polybasic acid is 0.05 to 0.2. 3. A process for producing a polyurethane foam, comprising reacting and foaming a polyisocyanate component with a polyol component containing the polyester polyol according to claim 1 or 2. 4. A polyol component used in producing an isocyanate prepolymer prepared from a polyisocyanate component and a polyol component, wherein the polyol component is (A) at least one phthalic anhydride selected from phthalic anhydride and o-phthalic acid. An acid component and an acid component containing an aliphatic polybasic acid,
(B) A method for producing an isocyanate prepolymer which is obtained by condensation polymerization of a polyhydric alcohol and contains a polyester polyol which is liquid at 40 ° C. and has a viscosity at 60 ° C. of 10,000 mPa · s or less. 5. The method for producing an isocyanate prepolymer according to claim 4, wherein the molar ratio of phthalic acid component / aliphatic polybasic acid is 0.05 to 0.55. 6. A method for producing a polyurethane foam, comprising reacting and foaming the isocyanate prepolymer obtained by the production method according to claim 4 with a polyol component.