JP3312476B2 - Method for producing flexible urethane foam - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a flexible urethane foam using a polyol containing an organic filler. More specifically, the present invention relates to a method for producing a flexible urethane foam using a polyol in which a diurea compound is dispersed.

[0002]

2. Description of the Related Art It is known to fill a powdery filler into polyurethane such as polyurethane foam. For example, Japanese Patent Publication No. 1-51492, Japanese Patent Publication No. 3-368.
No. 8 and U.S. Pat. No. 4,108,791. A method for producing polyurea as a filler is also known.

[0003]

However, when a powdery filler is filled into polyurethane such as polyurethane foam by the conventional technique, tensile strength, elongation and the like generally decrease. This is considered to be due to poor adhesion between the urethane resin and the filler. Therefore, it has been attempted to maintain the physical properties of the filler by subjecting the filler to a surface treatment with a fatty acid, a silane coupling agent, titanate, or the like, but this is not sufficient.

In the case of producing polyurea as a filler, for example, a method is generally known in which a polyurea produced in an appropriate solvent and a polyurethane produced in a separate solvent are mixed at an arbitrary ratio. However, this method is not preferable as an industrial polyurethane production method because the production process is complicated. Also, a method for producing polyurea in a polyol is already known,
In many of these, 20% by weight or more of polyurethane is composed of polyurea, and it is desired to obtain good physical properties with a small amount of filler. This can be said to be a method of producing polyurethane and polyurea separately.

An object of the present invention is to provide a flexible urethane foam which can obtain good physical properties even with a relatively small amount of filler and can be reinforced without significantly impairing other properties.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve such conventional problems, and as a result, have found that a diurea compound-dispersed polyol obtained by reacting a diisocyanate compound with an aromatic monoamine in a polyol is used. By using the same, good physical properties can be obtained even with a relatively small filler amount, and a flexible urethane foam which has been strengthened without greatly impairing other properties has been provided.
That is, the polyol component (A), the polyisocyanate (B
1) In a method for producing a flexible urethane foam using a foaming agent and an additive, the polyol component (A) includes:
Part or all of the aromatic monoamine (C) and the diisocyanate compound (B2) in the polyol (A1)
A flexible urethane foam production method characterized by being a diurea compound-dispersed polyol (A2) containing 0.1 to 20% by weight of a diurea compound obtained by the above reaction.

The polyol component (A) used in the present invention
Examples of the polyol (A3) other than (A2) include low-molecular-weight polyols, polyether-based polyols, polyester-based polyols, castor oil-based polyols, and polycarbonate polyols. These can be used alone or as a mixture of two or more.

[0008] As low molecular polyols, divalent ones such as ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol,
1,6-hexanediol, neopentyl glycol,
Examples of trivalent or higher valent (trivalent to octavalent) such as hydrogenated bisphenol A include glycerin, trimethylolpropane, hexanetriol, pentaerythritol, sorbitol, and souce. The low-molecular-weight polyol has an equivalent of 31 to 400, and the other polyol has an equivalent of 400 to 10000.
Containing one hydroxyl group.

The polyether polyol is preferably a polyether polyol having an equivalent weight of 300 to 5000 and having 2 to 4 hydroxyl groups in one molecule, for example, ethylene glycol, diethylene glycol, propylene glycol,
Glycols such as dipropylene glycol, glycerin, trimethylolethane, trimethylolpropane,
Hydroxyl-containing polyether polyols obtained by adding and polymerizing alkylene oxides such as ethylene oxide and propylene oxide to polyols such as pentaerythritol.

The polyester polyol is preferably a polyester polyol having an equivalent weight of 300 to 5,000 and having 2 to 4 hydroxyl groups in one molecule, for example, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, One or two compounds having at least two or more hydroxyl groups, such as 1,3-butanediol, 1,4-butanediol, tetramethylene glycol, hexamethylene glycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol and the like. It can be produced by a known method using at least one species and a polycarboxylic acid compound. Further, polyester polyols obtained by ring-opening polymerization of caprolactone are also included.

The castor oil-based polyol has an equivalent weight of 30.
Among those having a molecular weight of 0 to 5000, examples thereof include transesterified polyols of castor oil and castor oil or castor oil fatty acid with the low-molecular-weight polyols, polyether polyols and polyester polyols, or esterified polyols.

The polycarbonate polyols are those having an equivalent weight of 300 to 5,000, for example, an alcohol condensation reaction of glycols with dialkyl carbonates such as dimethyl and diethyl, a phenol condensation reaction of glycols with diphenyl carbonate, and a glycol phenol condensation reaction of glycols with ethylene carbonate. Examples include those obtained by an ethylene glycol condensation reaction. Examples of the glycols include aliphatic diols such as 1,6-hexanediol, diethylene glycol, propylene glycol, 1,4-butanediol, 3-methyl-1,5 pentanediol, and neopentyl glycol;
Alicyclic diols such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol are exemplified. A particularly preferred polyol (A3) is a polyether polyol containing three hydroxyl groups in one molecule and having an equivalent weight of 1,000 to 6,000.

The polyol (A1) used for the diurea compound-dispersed polyol (A2) in the polyol component (A) of the present invention is, for example, a polyester containing 2-3 hydroxyl groups per molecule and having an equivalent of 500-3000. Polyols and polyether polyols can be used. Particularly preferred are polyether polyols,
This involves reacting propylene oxide and ethylene oxide sequentially with a divalent or trivalent initiator to form
Obtained by making an equivalent amount of a primary hydroxyl-terminated polyether. Such compounds are described, for example, in US Pat. No. 4,394,491.

The aromatic monoamine (C) used in the present invention has no substituent other than an amino group or is meta-substituted, for example, aniline, metachloroaniline, metabromoaniline, metatoluidine, and These mixtures are mentioned. The amount of the aromatic monoamine is preferably 0.05 to 5.0 parts by weight based on 100 parts by weight of the polyol.

Diisocyanate compound (B2) used in the diurea compound-dispersed polyol (A2) of the present invention
Examples include diphenyltan diisocyanate, hydrides of diphenyltan diisocyanate, isophorone diisocyanate, and mixtures thereof.
Particularly preferred diurea compounds are the reaction products of aniline and 4,4'-diphenylmethane diisocyanate.

The compounding ratio of the aromatic monoamine (C) and the diisocyanate compound (B2) is 0.1 to 1.0 mol, preferably 0.4 to 0.6 mol, more preferably 0.4 mol to 1 mol of the aromatic monoamine. Is preferably 0.5 mol. NCO of one molecule of diisocyanate compound
The amino group of two aromatic monoamine molecules reacts one by one with two groups, and the obtained diurea compound is aggregated to have an average length of less than 10 μm, an average diameter of at least 4 and a melting point exceeding 200 ° C. It becomes an organic filler having the following.

The diurea compound-dispersed polyol (A2) of the present invention comprises about 60 parts by weight of a mixture containing 0.05 to 5.0 parts by weight of an aromatic monoamine (C) per 100 parts by weight of the polyol (A1). By stirring at 30 ° C. for 30 minutes, adding the diisocyanate compound in a ratio of 0.1 to 1.0 mol per 1 mol of the aromatic monoamine, stirring the mixture for 1 hour or more, and reacting the aromatic monoamine and the diisocyanate compound in the polyol. can get.

The diurea compound in the diurea compound-dispersed polyol of the present invention is preferably contained in an amount of 0.1 to 20 parts by weight. When the amount is less than 0.1% by weight, the effect as a reinforcing material is not exhibited, and when the amount exceeds 20 parts by weight, the viscosity of the diurea compound-dispersed polyol increases, which is not preferable because the work becomes difficult.

The polyisocyanate (B) used in the present invention
1) has, on average, at least two NCO groups in one molecule, and the NCO groups may be bonded to aromatic or fatty carbon atoms. Preferred aromatic isocyanates include, for example, 2,4- or 2,6-toluene diisocyanate, diphenylmethane diisocyanate (hereinafter abbreviated as MDI), p-phenylene diisocyanate, and polymethylene polyphenyl polyisocyanate (hereinafter abbreviated as polymeric MDI). ), And mixtures thereof. MDI and derivatives of the MDI prepolymer or its quasi-prepolymer are also effective. Particularly preferred aliphatic isocyanates include, for example, hydrogenated derivatives of the aromatic isocyanates, hexamethylene diisocyanate, isophorone diisocyanate, and cyclohexane diisocyanate. A particularly preferred polyisocyanate is polymeric MDI. The polyisocyanate (B1) having an NCO content of 0.5 to 30% by weight.
Prepolymers and quasi-prepolymers are also effective.

The diisocyanate compound is used in a proportion of 0.7 to 5, preferably 0.8 to 1.5, more preferably 0.95 to 1.2, NCO groups per equivalent of active hydrogen groups in the diurea compound-dispersed polyol. The reaction is allowed, but in cases involving the formation of an isocyanurate-containing polyurethane, a larger amount of the diisocyanate compound (B2) can be used.

The flexible urethane foam of the present invention is characterized in that it is produced using a diurea compound-dispersed polyol and a polyisocyanate as basic reaction components, but other polyols and additives can be used if necessary.
Examples of the additives include a foaming agent, a foam stabilizer, a catalyst, a surfactant, a viscosity reducing agent, a pigment or a dye, a flame retardant, an antioxidant, an ultraviolet absorber, a filler, and other auxiliaries.

As the foaming agent, water is preferable, but if necessary, it does not significantly affect the global environment.
Alternatively, a known material having few other problems can be used. The known blowing agents include methylene chloride, monochlorodifluoromethane, dichlorodifluoromethane, dichloromonofluoromethane, and so-called azo blowing agents,
Water, hydrocarbons, halogenated methane or mixtures thereof are preferred, including finely divided solids or other substances which generate gas under the conditions of the foaming reaction. Water is advantageously used in 0.5 to 10, preferably 1 to 5 parts per 100 parts by weight of polyol. The hydrocarbons and halogenated alkanes are advantageously used in an amount of 5 to 75 parts per 100 parts by weight of polyol.

Examples of the foam stabilizer include known ones generally used for producing polyurethane foam. Examples include a polydimethylsiloxane-polyalkylene oxide block polymer and a vinylsilane-polyalkylene polyol polymer.

As the catalyst, a known organic metal catalyst and a tertiary amine compound used for producing a polyurethane foam are used. As the organic metal catalyst, for example, dibutyltin dilaurate is preferable. Other catalysts include, for example, tertiary amines, diazahirocycloalkenes and salts thereof, and organometallic compounds described in U.S. Pat. No. 4,449,081, all of which may be used in combination. It is possible. The catalyst is polyol 1
0.001 to 0.5 parts of an organometallic catalyst is used based on 00 parts by weight. Tertiary amine is added in an amount of 0.1
Advantageously, it is used in the range of up to 3 parts.

[0025]

According to the present invention, a flexible urethane foam can be provided with a relatively small amount of organic filler without significantly impairing other properties. In addition, since the filler is produced in the polyol, it is a production method that is industrially sufficient and has excellent performance, so it is effective for furniture, beds, cushioning materials for automobile seats, automobile parts and other uses It is.

[0026]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In Examples and Comparative Examples, “parts” means “parts by weight”, and “%” means “% by weight”.

Example 1 Production of Diurea Compound-Dispersed Polyol In a four-necked flask equipped with a thermometer, a stirrer, and a nitrogen sealed tube, 2.2 parts of aniline was added with a trifunctional polyol (manufactured by Asahi Denka Kogyo, EL-823, molecular weight). (5000) 995 parts and stirred and mixed at 60 ° C. for 30 minutes. Next, 2.8 parts of MDI (manufactured by Nippon Polyurethane Industry Co., Ltd., Millionate MT) was added, and the mixture was reacted at 60 ° C. for 1 hour.
5% white diurea compound-dispersed polyol (A
2) was obtained. Production of Polyurethane Foam Molded Product 100 parts of the above polyol (A2), 3.5 parts of water as a blowing agent, 1.0 part of triethylenediamine (containing 66.7% of dipropylene glycol) as a catalyst, and Bis-
(2-dimethylaminoethyl) ether (containing 30% of dipropylene glycol) and 1.0 part of SZ-1306 (manufactured by Nippon Unicar) as a foam stabilizer were mixed in advance, and an MDI-based polyisocyanate (manufactured by Nippon Polyurethane Industry, Coronate 110) was added.
6) was heated to 25 ° C., and a mixture obtained by mixing at an NCO index of 100 was stirred with a homomixer for 10 seconds.
At the same time, pour it into the open mold and allow it to foam freely.
The mixture was poured into a 300 × 300 × 100 mm mold preheated to 5 ° C., demolded after 5 minutes, and cured at 25 ° C. for 16 hours to obtain a polyurethane foam molded product. Table 1 shows the physical property values of the obtained polyurethane foam molded product.

Example 2 To a four-necked flask equipped with a thermometer, a stirrer, and a nitrogen sealed tube, 4.3 parts of aniline and 990 parts of a trifunctional polyol (manufactured by Asahi Denka Kogyo KK, EL-823, molecular weight 5000) were added. And mixed at 60 ° C. for 30 minutes. Next, 5.7 parts of MDI (Millionate MT, manufactured by Nippon Polyurethane Industry Co., Ltd.) was added and 6 parts were added.
When reacted at 0 ° C. for 1 hour, a white diurea compound-dispersed polyol (A2) containing 1.0% of a diurea compound was obtained. Using the above polyol (A2), a polyurethane foam molded article similar to that of Example 1 was obtained. Table 1 shows the physical property values of the obtained polyurethane foam molded product.

Example 3 A white diurea compound-dispersed polyol (A2) containing 1.0% of the diurea compound obtained in Example 2 and a trifunctional polyol (GP-1000, molecular weight 1000, manufactured by Sanyo Chemical Industries) 10 A polyurethane foam molded article similar to that of Example 1 was obtained using the polyol to which the parts were added. Table 1 shows the physical property values of the obtained polyurethane foam molded product.

Comparative Example 1 Production of a polyurethane foam molded article 100 parts of the trifunctional polyol having a molecular weight of 5000 used in Example 1, 3.5 parts of water as a blowing agent, and triethylenediamine (dipropylene glycol 66.7%) as a catalyst
1.0 part and Bis- (2-dimethylaminoethyl) eth
er (containing 30% of dipropylene glycol) and 1.0 part of SZ-1306 (manufactured by Nippon Unicar) as a foam stabilizer were added in advance, and an MDI-based polyisocyanate (manufactured by Nippon Polyurethane Industry, Coronate 1106) was added at 25 ° C. Warm, N
A mixture mixed at a CO index of 100 was stirred with a homomixer for 10 seconds, and then poured into an open mold for free foaming, and at the same time, 300 × 30 preheated to 55 ° C.
It was poured into a mold of 0 × 100 mm, demolded after 5 minutes, and cured at 25 ° C. for 16 hours to obtain a polyurethane foam molded product. Table 1 shows the physical property values of the obtained polyurethane foam molded product.

Comparative Example 2 Polyurethane similar to that of Example 1 was prepared by using a polyol containing 0.5% of silica (Nihon Silica Kogyo Co., Ltd., Nip Seal) as an inorganic filler in the trifunctional polyol having a molecular weight of 5000 used in Example 1. A foam molding was obtained. Table 1 shows the physical property values of the obtained polyurethane foam molded product.

Comparative Example 3 A polyurethane foam molded product similar to that of Example 1 was obtained by using a polyol containing 1% of silica as an inorganic filler in the trifunctional polyol having a molecular weight of 5000 used in Example 1. Table 1 shows the physical property values of the obtained polyurethane foam molded product.

[Physical property test] The test was carried out based on the methods of JIS K 6382 and JIS K 6402.

[0034]

[Table 1]

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-50-159592 (JP, A) JP-A-63-22818 (JP, A) JP-A-51-114497 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) C08G 18/00 C08G 18/48-18/50 C08G 18/06-18/08

Claims (1)

(57) [Claims] 1. A method for producing a flexible urethane foam using a polyol component (A), a polyisocyanate (B1), a foaming agent and an additive, wherein part or all of the polyol component (A) is a polyol (A1). )) Is a diurea compound-dispersed polyol (A2) containing 0.1 to 20% by weight of a diurea compound obtained by a reaction of an aromatic monoamine (C) and a diisocyanate compound (B2). Method.