JP2013018843A - Method for producing semi-hard polyurethane foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a polyurethane foam of a high hardness having a high mechanical property.SOLUTION: The method for producing a polyurethane foam includes reacting a strength improving agent (A1), which is a strength improving agent for producing a polyurethane foam represented by formula (I), a polyol, and a polyisocyanate component.

Description

  The present invention relates to a method for producing a semi-rigid polyurethane foam, and more particularly to a method for producing a semi-rigid polyurethane foam suitable for producing interior materials for automobiles such as instrument panels and steering wheels.

In recent years, environmental considerations and cost reduction demands are strong, and in automobile applications, there is a demand for lower density polyurethane foam in order to comply with fuel efficiency regulations.
At present, the amount of water used as a foaming agent tends to increase to meet the demand for lower density. Increasing the amount of water used (Non-Patent Document 1, etc.) can increase the amount of carbon dioxide generated during foam production and is effective in reducing the density of semi-rigid polyurethane foam. As the density decreases, the foam hardness decreases. Specific techniques for improving the hardness of polyurethane foam include a method of increasing the amount of the crosslinking agent used (Non-patent Document 1) and a method of dispersing a polymer in a resin (Patent Document 1). In this method, mechanical properties such as elongation and tensile strength of semi-rigid polyurethane foam are insufficient, and problems such as poor flexibility and toughness and poor tactile sensation remain. Materials are needed.

JP-A-9-309937 JP-A-6-65346

  An object of the present invention is to provide a method for producing a semi-rigid polyurethane foam having high mechanical properties (tensile strength, tear strength) and high hardness.

The inventors of the present invention have reached the present invention as a result of studies to achieve the above object.
That is, the present invention is a method for producing a semi-rigid polyurethane foam by reacting a polyol component (A) and an organic polyisocyanate component (B) in the presence of a catalyst (C) and a foaming agent (D). (A) is a method for producing a semi-rigid polyurethane foam containing the following strength improver (A1) and polyol (A2).
Strength improver (A1): Strength improver for producing polyurethane foam represented by the following general formula (I).

[In the general formula (I), R1 represents a residue obtained by removing one active hydrogen from an active hydrogen-containing compound. A plurality of R1 may be the same or different. ; Y represents the residue remove | excluding the carboxyl group from trivalent or more aromatic polycarboxylic acid (e). The aromatic ring of Y is composed of carbon atoms. The substituent of the aromatic ring may be a hydrogen atom or another substituent, but at least one substituent is a hydrogen atom. A is an integer satisfying 0 ≦ a ≦ (the number of aromatic ring substituents−2). B is an integer satisfying 0 ≦ b ≦ (the number of aromatic ring substituents−2). A + b is an integer satisfying 2 ≦ a + b ≦ (the number of aromatic ring substituents−2). Z represents a residue obtained by removing m active hydrogens from an active hydrogen-containing compound having a valence of at least m; M represents an integer of 1 to 10; ]
Polyol (A2): A polyether polyol other than (A1) having a number average functional group number of 2 to 4, a hydroxyl value of 20 to 150 mgKOH / g, and a content of terminal oxyethylene units of less than 30% by weight.

  The semi-rigid polyurethane foam obtained by the production method of the present invention has high mechanical properties (tensile strength, tear strength) and high hardness.

  In the present invention, the polyol component (A) contains the following strength improver (A1) and polyol (A2).

  The strength improver (A1) has a structure represented by the following general formula (I).

  In general formula (I), R1 represents a residue obtained by removing one active hydrogen from an active hydrogen-containing compound. Examples of the active hydrogen-containing compound include a hydroxyl group-containing compound, an amino group-containing compound, a carboxyl group-containing compound, a thiol group-containing compound, and a phosphate compound; a compound having two or more active hydrogen-containing functional groups in the molecule. These active hydrogen-containing compounds can be used either alone or in combination. That is, the plurality of R1s may be the same or different.

Examples of the hydroxyl group-containing compound include monohydric alcohols, divalent to octavalent polyhydric alcohols, phenols and polyhydric phenols. Specifically, monohydric alcohols such as methanol, ethanol, butanol, octanol, benzyl alcohol, naphthylethanol; ethylene glycol, propylene glycol, 1,3 and 1,4-butanediol, 1,6-hexanediol, 1, Dihydric alcohols such as 10-decanediol, diethylene glycol, neopentyl glycol, cyclohexanediol, cyclohexanedimethanol, 1,4-bis (hydroxymethyl) cyclohexane and 1,4-bis (hydroxyethyl) benzene; glycerin and trimethylolpropane Trihydric alcohols such as pentaerythritol, sorbitol, mannitol, sorbitan, diglycerin, dipentaerythritol, sucrose, glucose, mannose, fructose, methyl 4- to 8-valent alcohols such as lucoside and derivatives thereof; phenol, phloroglucin, cresol, pyrogallol, catechol, hydroquinone, bisphenol A, bisphenol F, bisphenol S, 1-hydroxynaphthalene, 1, 3, 6 , 8-tetrahydroxynaphthalene, anthrol, phenols such as 1,4,5,8-tetrahydroxyanthracene and 1-hydroxypyrene; polybutadiene polyol; castor oil-based polyol; (co) heavy of hydroxyalkyl (meth) acrylate Examples thereof include polyfunctional (eg, 2-100 functional group) polyols such as coalesced and polyvinyl alcohol, condensates of phenol and formaldehyde (novolak), and polyphenols described in US Pat. No. 3,265,641.
(Meth) acrylate means methacrylate and / or acrylate, and the same applies hereinafter.

  Examples of the amino group-containing compound include amines, polyamines and amino alcohols. Specifically, ammonia; monoamines such as C1-C20 alkylamine (butylamine and the like) and aniline; aliphatic polyamines such as ethylenediamine, hexamethylenediamine and diethylenetriamine; heterocyclics such as piperazine and N-aminoethylpiperazine Polyamines; alicyclic polyamines such as dicyclohexylmethanediamine and isophoronediamine; aromatic polyamines such as phenylenediamine, tolylenediamine and diphenylmethanediamine; alkanolamines such as monoethanolamine, diethanolamine and triethanolamine; and dicarboxylic acids Polyamide polyamine obtained by condensation with excess polyamine; polyether polyamine; hydrazine (such as hydrazine and monoalkylhydrazine), dihydrazide ( Etc. Haq acid dihydrazide and dihydrazide terephthalate), guanidine (butyl guanidine and 1-cyanoguanidine, etc.); dicyandiamide; and the like.

  Examples of the carboxyl group-containing compound include aliphatic monocarboxylic acids such as acetic acid and propionic acid; aromatic monocarboxylic acids such as benzoic acid; aliphatic polycarboxylic acids such as succinic acid, fumaric acid, sebacic acid and adipic acid; phthalic acid , Isophthalic acid, terephthalic acid, trimellitic acid, naphthalene-1,4 dicarboxylic acid, naphthalene-2,3,6 tricarboxylic acid, pyromellitic acid, diphenic acid, 2,3-anthracene dicarboxylic acid, 2,3,6- Examples thereof include aromatic polycarboxylic acids such as anthracentricarboxylic acid and pyrene dicarboxylic acid; polycarboxylic acid polymers (functional group number: 2 to 100) such as (co) polymers of acrylic acid, and the like.

  Examples of the thiol group-containing compound include monofunctional phenylthiol, alkylthiol, and polythiol compounds. Examples of the polythiol include divalent to octavalent polyvalent thiols. Specific examples include ethylenedithiol and 1,6-hexanedithiol.

  Examples of phosphoric acid compounds include phosphoric acid, phosphorous acid, and phosphonic acid.

  As the active hydrogen-containing compound, a compound having two or more active hydrogen-containing functional groups (hydroxyl group, amino group, carboxyl group, thiol group, phosphate group, etc.) in the molecule can also be used.

  Further, as the active hydrogen-containing compound, an alkylene oxide adduct of the active hydrogen-containing compound can also be used.

  Examples of the alkylene oxide (hereinafter abbreviated as AO) to be added to the active hydrogen-containing compound include AO having 2 to 6 carbon atoms, such as ethylene oxide (hereinafter abbreviated as EO), 1,2-propylene oxide (hereinafter abbreviated as PO). ), 1,3-propyloxide, 1,2-butylene oxide, 1,4-butylene oxide, and the like. Of these, PO, EO, and 1,2-butylene oxide are preferable from the viewpoints of properties and reactivity. When two or more types of AO are used (for example, PO and EO), block addition or random addition may be used, or a combination thereof may be used.

  Further, as the active hydrogen-containing compound, an active hydrogen-containing compound (polyester compound) obtained by a condensation reaction between the active hydrogen-containing compound and a polycarboxylic acid (aliphatic polycarboxylic acid or aromatic polycarboxylic acid) is used. Can do. In the condensation reaction, one type of active hydrogen-containing compound and polycarboxylic acid may be used, or two or more types may be used in combination.

The aliphatic polycarboxylic acid means a compound that satisfies the following (1) and (2).
(1) One molecule has two or more carboxyl groups.
(2) The carboxyl group is not directly bonded to the aromatic ring.

  Aliphatic polycarboxylic acids include succinic acid, adipic acid, sebacic acid, maleic acid and fumaric acid.

The aromatic polycarboxylic acid means a compound that satisfies the following (1) to (3).
(1) One molecule has one or more aromatic rings.
(2) The number of carboxyl groups in one molecule is 2 or more.
(3) The carboxyl group is directly bonded to the aromatic ring.

  Aromatic polycarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid, 2,2'-bibenzyldicarboxylic acid, trimellitic acid, hemilitic acid, trimesic acid, pyromellitic acid and naphthalene-1,4 dicarboxylic acid, naphthalene Examples include aromatic polycarboxylic acids having 8 to 18 carbon atoms such as -2,3,6 tricarboxylic acid, diphenic acid, 2,3-anthracene dicarboxylic acid, 2,3,6-anthracentricarboxylic acid and pyrene dicarboxylic acid.

  Moreover, when performing condensation reaction of polycarboxylic acid and an active hydrogen containing compound, the anhydride and lower alkyl ester of polycarboxylic acid can also be used.

  From the viewpoint of handling the strength improver and improving the mechanical properties (tensile strength, compression hardness) of the polyurethane foam, the active hydrogen-containing compound R1 includes a hydroxyl group-containing compound, an amino group-containing compound, and these AO adducts and activity. A polyester compound obtained by a condensation reaction of a hydrogen-containing compound and a polycarboxylic acid is preferable, and methanol, ethanol, butanol, ethylene glycol, propylene glycol, glycerin, pentaerythritol, sorbitol, sucrose, benzyl alcohol, phenol, methyl are more preferable. Amine, dimethylamine, ethylamine, diethylamine, butylamine, dibutylamine, phenylamine, diphenylamine, their EO and / or PO adducts, these active hydrogen compounds and phthalic acid and / or Condensates of phthalic acid are preferred.

  In general formula (I), Y represents the residue remove | excluding the carboxyl group from trivalent or more aromatic polycarboxylic acid (e). The aromatic ring of Y is composed of carbon atoms. The substituent of the aromatic ring may be a hydrogen atom or another substituent, but at least one substituent is a hydrogen atom. That is, the aromatic ring of Y has at least one hydrogen atom bonded to the carbon atom constituting the aromatic ring.

  Other substituents are alkyl group, vinyl group, allyl group, cycloalkyl group, halogen atom, amino group, carbonyl group, carboxyl group, hydroxyl group, hydroxyamino group, nitro group, phosphino group, thio group, thiol group Aldehyde group, ether group, aryl group, amide group, cyano group, urea group, urethane group, sulfone group, ester group and azo group. From the viewpoints of improving mechanical properties (elongation, tensile strength, compression hardness) and cost, the other substituents are preferably alkyl groups, vinyl groups, allyl groups, amino groups, amide groups, urethane groups, and urea groups.

  As the arrangement of substituents on Y, from the viewpoint of improving mechanical properties, two carbonyl groups are adjacent to each other, and hydrogen is arranged as a substituent between the third carbonyl group and the first or second carbonyl group. The structure is preferred.

  Examples of trivalent or higher aromatic polycarboxylic acids (e) constituting Y include trimellitic acid, hemilitic acid, trimesic acid, pyromellitic acid, naphthalene-2,3,6 tricarboxylic acid and 2,3,6-anthracene. An aromatic polycarboxylic acid having 8 to 18 carbon atoms such as tricarboxylic acid is exemplified.

  From the viewpoint of handling the strength improver (A1) and improving the mechanical properties (tensile strength, tear strength, compression hardness) of polyurethane foam, (e) used for Y is preferably a monocyclic compound, more preferably trimellit. Acid and pyromellitic acid.

  In general formula (I), a is an integer that satisfies 0 ≦ a ≦ the number of aromatic ring substituents−2. The number of aromatic ring substituents is the number of substituents bonded to the carbon atoms constituting the aromatic ring. For example, a monocyclic aromatic ring composed of 6 carbons has 6 aromatic ring substituents, and a can be 0 to 4. When the aromatic ring is a monocyclic aromatic ring, a is preferably 2 or 3 from the viewpoint of improving mechanical properties (tensile strength, tear strength, compression hardness).

  In general formula (I), b is an integer satisfying 0 ≦ b ≦ number of aromatic ring substituents−2. For example, in a monocyclic aromatic ring composed of 6 carbons, the number of aromatic ring substituents is 6, and b can be 0 to 4. When the aromatic ring is a monocyclic aromatic ring, b is preferably 0 or 1 and more preferably b is 0 from the viewpoint of the curing rate of the foam.

  In the general formula (I), a + b is an integer satisfying 2 ≦ (a + b) ≦ the number of aromatic ring substituents−2. For example, a monocyclic aromatic ring composed of 6 carbons has 6 aromatic ring substituents, and can take 0 to 4 as a + b. When the aromatic ring is a monocyclic aromatic ring, a + b is preferably 2 or 3 from the viewpoint of improving mechanical properties (tensile strength, tear strength, compression hardness).

  Z in the general formula (I) represents a residue obtained by removing m active hydrogens from an active hydrogen-containing compound having an m valence or higher. The active hydrogen-containing compound referred to here includes the active hydrogen-containing compound represented by R1 described above. The active hydrogen-containing compound represented by Z may be the same as part of R1, but at least one of R1 and Z is different from the viewpoint of improving mechanical properties (tensile strength, tear strength, compression hardness). It is preferably a group, and more preferably, all R 1 and Z are different groups.

In general formula (I), m represents an integer of 1 to 10.
From the viewpoint of handling the strength improver (A1) and improving the mechanical properties (tensile strength, tear strength, compression hardness) of the polyurethane foam, Z includes a hydroxyl group-containing compound, an amino group-containing compound, these AO adducts, and these It is preferable to use a condensate of polycarboxylic acid and m is preferably 1-8.

In the present invention, the hydroxyl value (mgKOH / g) of the strength improver (A1) is preferably from 0 to 700, more preferably from 0 to 600, and further from the viewpoint of handling (viscosity) and tensile strength during molding. Preferably it is 20-400.
In the present invention, the hydroxyl value is measured in accordance with JISK-1557.
Moreover, that the hydroxyl value of (A1) is 0 means that none of R1, Y, and Z has a hydroxyl group in general formula (I).

In the present invention, the aromatic ring concentration (mmol / g) of the strength improver (A1) is preferably 0.1 to 10.0, more preferably 0.2 to 9.5, from the viewpoint of improving the tensile strength. More preferably, it is 0.3-9.0.
In addition, the aromatic ring concentration of (A1) means the number of moles of the aromatic ring in 1 g of the strength improver (A1).

  The content of Y derived from (e) having 3 or more valences is 0.5 to 0.5 from the viewpoint of improving mechanical properties (tensile strength, tear strength, compression hardness) on the basis of the number average molecular weight of the strength improver (A1). It is preferably 50%, more preferably 4 to 47%, and still more preferably 6 to 45%.

  From the viewpoint of handling, the content of the strength improver (A1) based on the weight of the polyol component (A) is preferably 1 to 99% by weight, more preferably 1 to 50% by weight, and still more preferably 1 -40% by weight, particularly preferably 2 to 35% by weight.

  Examples of the polyol (A2) used in the present invention include compounds having a structure in which AO is added to an active hydrogen-containing compound.

Examples of the polyol (A2) include compounds having a structure in which AO is added to the divalent to tetravalent or higher active hydrogen-containing compounds by a method described later, and two or more of them may be used in combination. .
AO includes PO and EO. AO preferably contains only these, but may be an adduct in which other AO is used in combination within a range of 10% by weight or less (particularly 5% by weight or less) in AO.
As an addition format of AO including PO and EO, a block addition in the order of PO and EO is preferable.

The number average functional group number of the polyol (A2) is 2 to 4, and the number average functional group number may be 2 to 4 even if the number of functional groups other than this range is included (the average functionality of other polyols). The same applies to the radix). In the present invention, the number of functional groups of the polyol is considered to be the same as the number of functional groups of the starting material. In the present invention, the average functional group number means the number average functional group number.
The hydroxyl value of the polyol (A2) is 20 to 150 (mg KOH / g, and the following hydroxyl values are the same), and preferably 23 to 130 from the viewpoint of foam hardness and elongation physical properties.
The content of the terminal oxyethylene unit of the polyol (A2) (hereinafter, the oxyethylene unit is described as EO unit) is less than 30% by weight, preferably from the viewpoint of sufficiently curing and reducing closed cells. 10 to 25% by weight.

  The content of the polyol (A2) based on the weight of the polyol component (A) is preferably from 1 to 99% by weight, more preferably from 10 to 99% from the viewpoint of improving mechanical properties (tensile strength, tear strength, elongation). 80% by weight, then more preferably 20 to 70% by weight, particularly preferably 55 to 98% by weight. In the present invention, when the polyol (A2) is contained in the polymer polyol to be used, the polyol component (A) is handled as containing the polyol (A2).

Using the polyol (A2) as at least part of the polyol composition (A) includes using a polymer polyol obtained by polymerizing the vinyl monomer (m) in (A2).
The polymer polyol is a polymer polyol in which polymer particles (P) are dispersed in (A2).
For example, it can be produced by polymerizing the vinyl monomer (m) by an ordinary method in the presence of a radical polymerization initiator. Specific examples of the polymerization method include those described in US Pat. No. 3,383,351, Japanese Examined Patent Publication No. 39-25737, and the like.

  As the radical polymerization initiator, those that generate a free radical to initiate polymerization can be used, for example, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile). ) And 2,2′-azobis (2-methylbutyronitrile) and the like; organic peroxides such as dibenzoyl peroxide, dicumyl peroxide, benzoyl peroxide, lauroyl peroxide and persuccinic acid; Examples thereof include inorganic peroxides such as persulfates and perborates. In addition, these can use 2 or more types together.

As vinyl monomer (m), aromatic vinyl monomer (m1), unsaturated nitrile (m2), (meth) acrylic acid ester (m3), other vinyl monomers (m4), and two or more of these Of the mixture.
Examples of (m1) include styrene, α-methylstyrene, hydroxystyrene, chlorostyrene, and the like.
Examples of (m2) include acrylonitrile and methacrylonitrile.
(M3) is composed of C, H and O atoms, for example, (meth) acrylic acid alkyl ester (the alkyl group has 1 to 24 carbon atoms) [for example, methyl (meth) acrylate, butyl (meta ) Acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, eicosyl (meth) acrylate and docosyl (meth) acrylate], hydroxyalkyl (2 to 5 carbon atoms) (meth) acrylate [for example, Hydroxyethyl (meth) acrylate] and hydroxypolyoxyalkylene mono (meth) acrylate [for example, an alkylene group having 2 to 4 carbon atoms and a polyoxyalkylene chain having a number average molecular weight of 200 to 1000].

(M4) includes ethylenically unsaturated carboxylic acid and derivatives thereof, specifically (meth) acrylic acid and (meth) acrylamide, etc .; aliphatic or alicyclic hydrocarbon monomers, specifically alkene ( Ethylene, propylene, norbornene, etc.), alkadienes (butadiene, etc.); fluorine-based vinyl monomers, specifically fluorine-containing (meth) acrylates (perfluorooctylethyl methacrylate, perfluorooctylethyl acrylate, etc.), etc .; chlorine Vinyl-based monomers, specifically vinylidene chloride, etc .; nitrogen-containing vinyl monomers other than those mentioned above, specifically nitrogen-containing (meth) acrylates (such as diaminoethyl methacrylate and morpholinoethyl methacrylate); and vinyl-modified silicones Etc.
Among these (m), (m1) and (m2) are preferable, and styrene and / or acrylonitrile are particularly preferable.

The weight ratio of (m1), (m2), (m3) and (m4) in the vinyl monomer (m) can be changed according to the required physical properties of the polyurethane and is not particularly limited. An example is as follows.
(M1) and / or (m2) is preferably 50 to 100%, more preferably 80 to 100% based on the weight of (m). The weight ratio of (m1) and (m2) is not particularly limited, but is preferably 0/100 to 80/20. (M3) is preferably 0 to 50%, more preferably 0 to 20%. (M4) is preferably 0 to 10%, more preferably 0 to 5%.
Further, in addition to these monofunctional monomers, a small amount (preferably 0.05 to 1%) of a bifunctional or higher (preferably 2 to 8 functional) polyfunctional vinyl monomer (m5) is used in (m). As a result, the strength of the polymer can be further improved. Examples of (m5) include divinylbenzene, ethylene di (meth) acrylate, polyalkylene (alkylene group having 2 to 8 carbon atoms, degree of polymerization: 2 to 10) glycol di (meth) acrylate, pentaerythritol triallyl ether and trialkyl ether. And methylolpropane tri (meth) acrylate.

  The polyol component (A) used in the present invention may contain a polyol (A3) other than the above-described strength improver (A1) and polyol (A2). (A3) is a polyol used for the production of a conventional polyurethane foam, and other than (A1) and (A2) can be used. Examples of (A3) include compounds having a structure in which AO is added to an active hydrogen-containing compound, and can be preferably used.

  The content of the other polyol (A3) based on the weight of the polyol component (A) is preferably 0 to 89% by weight, more preferably from the viewpoint of improving mechanical properties (tensile strength, tear strength, elongation). It is 0 to 79% by weight, then more preferably 0 to 43% by weight, particularly preferably 0 to 20% by weight.

  In producing the polyol composition (A), any known method may be used for mixing the polyol (A1) and the polyol (A2).

  As an organic polyisocyanate component (B) used by this invention, what is necessary is just a compound which has two or more isocyanate groups in a molecule | numerator, and what is normally used for manufacture of a polyurethane foam can be used. Examples of such isocyanates include aromatic polyisocyanates, aliphatic polyisocyanates, alicyclic polyisocyanates, araliphatic polyisocyanates, and modified products thereof (for example, urethane groups, carbodiimide groups, allophanate groups, urea groups, burettes). Group, an isocyanurate group, or an oxazolidone group-containing modified product) and a mixture of two or more thereof.

As aromatic polyisocyanate, C6-C16 aromatic diisocyanate, C6-C20 aromatic triisocyanate, and crude products of these isocyanates (excluding carbon in NCO group; the following isocyanates are also the same), etc. Is mentioned. Specific examples include 1,3- and / or 1,4-phenylene diisocyanate, 2,4- and / or 2,6-tolylene diisocyanate (TDI), crude TDI, 2,4′- and / or 4, Examples include 4′-diphenylmethane diisocyanate (MDI), polymethylene polyphenylene polyisocyanate (crude MDI), naphthylene-1,5-diisocyanate, triphenylmethane-4,4 ′, 4 ″ -triisocyanate, and the like.
Examples of the aliphatic polyisocyanate include aliphatic diisocyanates having 6 to 10 carbon atoms. Specific examples include 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, and the like.
Examples of the alicyclic polyisocyanate include alicyclic diisocyanates having 6 to 16 carbon atoms. Specific examples include isophorone diisocyanate (IPDI), 4,4′-dicyclohexylmethane diisocyanate, 1,4-cyclohexane diisocyanate, norbornane diisocyanate, and the like.
Examples of the araliphatic polyisocyanate include araliphatic diisocyanates having 8 to 12 carbon atoms. Specific examples include xylylene diisocyanate, α, α, α ′, α′-tetramethylxylylene diisocyanate, and the like.
Specific examples of the modified polyisocyanate include urethane-modified MDI, carbodiimide-modified MDI, sucrose-modified TDI, and castor oil-modified MDI.

  The organic polyisocyanate component (B) is preferably an aromatic polyisocyanate from the viewpoint of mechanical properties of the foam, more preferably 60% or more of TDI, crude TDI, and modified products thereof. One or more polyisocyanates (these isocyanates are referred to as TDI-based polyisocyanates) and 40% or less of other polyisocyanates (preferably MDI, crude MDI, and modified products of these isocyanates) ). Particularly preferably, the amount of TDI-based polyisocyanate is 70 to 95%.

  In the present invention, the catalyst (C) may be an ordinary catalyst that accelerates the urethanization reaction. Examples thereof include triethylenediamine, bis (N, N-dimethylamino-2-ethyl) ether, N, N, N ′, N′-tetramethylhexamethylenediamine, PO adduct of N, N-dimethylaminopropylamine, tertiary amines such as 1,8-diazabicyclo [5,4,0] undecene-7 and carboxylates thereof , Metal carboxylates such as potassium acetate, potassium octylate and stannous octoate, and organometallic compounds such as dibutyltin dilaurate.

Water can be used as the foaming agent (D) in the present invention.
In the present invention, the amount of water used is preferably 0.01 to 5.0 with respect to 100 parts by weight of the polyol component (A) (hereinafter, “parts” means “parts by weight”) from the viewpoint of mechanical properties of the foam. Part, more preferably 0.02 to 3.0 part.
It is preferable to use only water as the foaming agent. If necessary, hydrogen atom-containing halogenated hydrocarbons, low-boiling hydrocarbons, liquefied carbon dioxide gas or the like may be used.

Specific examples of hydrogen atom-containing halogenated hydrocarbon-based blowing agents include those of the HCFC (hydrochlorofluorocarbon) type (for example, HCFC-123, HCFC-141b, HCFC-22 and HCFC-142b); those of the HFC (hydrofluorocarbon) type (For example, HFC-134a, HFC-152a, HFC-356mff, HFC-236ea, HFC-245ca, HFC-245fa, and HFC-365mfc).
Among these, HCFC-141b, HFC-134a, HFC-356mff, HFC-236ea, HFC-245ca, HFC-245fa, and HFC-365mfc and mixtures of two or more thereof are preferred.
The amount of hydrogen atom-containing halogenated hydrocarbon used is preferably 0.01 to 50 parts or less, more preferably 0.02 to 45 parts or less per 100 parts of (A).

The low boiling point hydrocarbon is usually a hydrocarbon having a boiling point of −5 to 70 ° C., and specific examples thereof include butane, pentane, cyclopentane, and mixtures thereof. When the low-boiling hydrocarbon is used, the amount used is preferably 0.01 to 30 parts, more preferably 0.02 to 25 parts, per 100 parts of (A).
The amount of liquefied carbon dioxide used is preferably 0.01 to 30 parts or less, more preferably 0.02 to 25 parts or less per 100 parts of (A).

In the present invention, if necessary, other auxiliary components as described below may be used and reacted in the presence thereof.
For example, foam stabilizer (dimethylsiloxane, polyether-modified dimethylsiloxane, etc.), colorant (dye, pigment), plasticizer (phthalate ester, adipic acid ester, etc.), organic filler (synthetic short fiber, thermoplastic) Or hollow microspheres made of thermosetting resins), flame retardants (phosphate esters, halogenated phosphate esters, etc.), anti-aging agents (triazoles, benzophenones, etc.), antioxidants (hindered phenols, hindered amines) In the presence of a known auxiliary component such as a system). Regarding the usage-amount of these auxiliary components with respect to 100 parts of polyol components (A), a foam stabilizer becomes like this. Preferably it is 10 parts or less, More preferably, it is 0.1-5 parts. The colorant is preferably 10 parts or less. The plasticizer is preferably 10 parts or less, more preferably 5 parts or less. The organic filler is preferably 50 parts or less, more preferably 30 parts or less. The flame retardant is preferably 30 parts or less, more preferably 1 to 20 parts. The anti-aging agent is preferably 5 parts or less, more preferably 0.01 to 3 parts. The antioxidant is preferably 5 parts or less, more preferably 0.01 to 3 parts.

  In the production method of the present invention, the isocyanate index [(NCO group / active hydrogen atom-containing group) equivalent ratio × 100] (NCO index) in the production of polyurethane foam is preferably 80 to 80 from the viewpoint of mechanical properties of the foam. 130, more preferably 85-125.

  A specific example of a method for producing a polyurethane foam by the method of the present invention is as follows. First, a predetermined amount of a polyol component (A), a catalyst (C), a foaming agent (D), and other auxiliary components are mixed if necessary. Subsequently, this mixture (polyol premix) and organic polyisocyanate component (B) are rapidly mixed using a polyurethane foaming machine or a stirrer. The obtained liquid mixture is poured into a mold (for example, 25 to 120 ° C.), and is demolded after a predetermined time to obtain a semi-rigid polyurethane foam.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited by this. Hereinafter, unless otherwise specified, “%” represents “% by weight” and “parts” represents “parts by weight”.

Production Example 1 [Production of Strength Improvement Agent A1-1]
In a stainless steel autoclave with a stirrer and a temperature controller, 1 mol of glycerin PO adduct (Sanyox GP-1500 manufactured by Sanyo Chemical Industries, Ltd .; number average molecular weight 1500, hydroxyl value 112.0), 6 mol of phthalic anhydride and Half esterification was performed by charging 0.010 mol of an alkali catalyst (N-ethylmorpholine) and reacting at 0.20 MPa and 120 ± 10 ° C. for 1 hour in a nitrogen atmosphere. Thereafter, 6 mol of EO was added dropwise over 5 hours while controlling the pressure to be 80 ± 10 ° C. and a pressure of 0.50 MPa or less, followed by aging at 80 ± 10 ° C. for 1 hour. Cool to room temperature, charge 1 mol of trimellitic anhydride, and after half-esterification at 0.20 MPa and 120 ± 10 ° C. for 1 hour, 2 mol of EO is 80 ± 10 ° C. and the pressure is 0.5 MPa or less. While being controlled, the solution was dropped over 2 hours and then aged at 80 ± 10 ° C. for 1 hour. After completion of aging, the alkali catalyst was removed under reduced pressure at 10 kPa for 1 hour to obtain a strength improver A1-1. The measured values of A1-1 are shown in Table 1.

Production Example 2 [Production of Strength Improvement Agent A1-2]
An autoclave similar to Production Example 1 was charged with 1 mol of polypropylene glycol (PP-2000), 2 mol of phthalic anhydride and 0.010 mol of an alkali catalyst (N-ethylmorpholine), 0.20 MPa in a nitrogen atmosphere, Half-esterification was performed by reaction at 120 ± 10 ° C. for 1 hour. Thereafter, 2 mol of EO was added dropwise over 5 hours while controlling the pressure to be 80 ± 10 ° C. and a pressure of 0.50 MPa or less, followed by aging at 120 ± 10 ° C. for 1 hour. After cooling to room temperature, charging 2 mol of trimellitic anhydride and esterifying at 0.20 MPa and 120 ± 10 ° C. for 1 hour, 4 mol of EO is 80 ± 10 ° C. and the pressure is 0.5 MPa or less. The solution was dropped over 2 hours under control, and then aged at 80 ± 10 ° C. for 1 hour. After completion of aging, the alkali catalyst was removed under reduced pressure at 10 kPa for 1 hour to obtain a strength improver A1-2. The measured values of A1-2 are shown in Table 1.

Production Example 3 [Production of Strength Improvement Agent A1-3]
In Production Example 1, strength improver A1-3 was obtained in the same manner as in Production Example 2 except that PO6 mol was used instead of EO6 mol. The measured values of A1-3 are shown in Table 1.

<Production Examples 4 to 14 Production of strength improver>
Hereinafter, the production of the strength improvers A1-4 to A1-14 will be described. The measured values of the obtained strength improver are shown in Table 1. In addition, it describes below about the thing which is not described in the manufacture examples 1-3 among the active hydrogen containing compounds currently used in manufacture of A1-4 to A1-14. Those not described can be easily obtained as reagents.

(1) Glycol-modified product / PEG-200 (ethylene glycol EO adduct; number average molecular weight 200, hydroxyl value 560, “PEG-200” manufactured by Sanyo Chemical Industries, Ltd.)
PEG-2000 (ethylene glycol EO adduct; number average molecular weight 2000, hydroxyl value 56.1, “PEG-2000” manufactured by Sanyo Chemical Industries, Ltd.)
Polyol (III) (propylene glycol POEO adduct: number average molecular weight 900, hydroxyl value 125)
In an autoclave similar to Production Example 1, 1 mol of propylene glycol and 9.0 mmol of KOH were charged and dehydrated at 130 ± 5 ° C. and 10 kPa for 1 hour. After completion of the dehydration, 14.0 mol of PO and 2.0 mol of EO were added dropwise over 2 hours while controlling to 130 ° C. ± 5 ° C. and 0.5 MPa or less, followed by aging for 2 hours. After completion of aging, the mixture was cooled to 90 ± 5 ° C., 2% by weight of water and 2% by weight of KYOWARD 600 (manufactured by Kyowa Chemical Co., Ltd .; synthetic silicate) were added and treated for 1 hour. After taking out from the autoclave, it was filtered using 1 micron filter paper and dehydrated under reduced pressure to obtain polyol (III).

(2) Modified glycerin / polyol (IV) (glycerin, phthalic anhydride, PO, EO copolymer; number average molecular weight 3000, hydroxyl value 56.1)
In the same autoclave as in Production Example 1, 1 mol of glycerin PO adduct (GP-1500), 4 mol of phthalic anhydride, and 0.10 mol of N-ethylmorpholine were charged and reacted at 120 ± 10 ° C. for 1 hour in a nitrogen atmosphere. And half esterification was performed. Thereafter, 2.4 mol of EO was added dropwise over 2 hours while controlling the pressure to be 80 ± 10 ° C. and a pressure of 0.50 MPa or less, followed by aging for 3 hours. After completion of aging, N-ethylmorpholine was removed under reduced pressure at 100 ± 10 ° C. and 10 kPa for 1 hour to obtain polyol (IV).

(3) Modified sorbitol / SP-750 (sorbitol PO adduct; number average molecular weight 690, hydroxyl value 490, “Sannik SP-750” manufactured by Sanyo Chemical Industries, Ltd.)

(4) Sucrose modified product / RP-410A (sucrose PO adduct; number average molecular weight 1070, hydroxyl value 420, “Sanix RP-410A” manufactured by Sanyo Chemical Industries, Ltd.)

The strength improvers A1-4 to 7 were produced by the following production method using the raw materials and the amount (moles) shown in Table 2, respectively. An example will be described in A1-4.
1 mol of PEG-200 (Z constituent raw material), 1 mol of trimellitic anhydride (Y constituent raw material), 2.2 mol of triethylamine as a catalyst, and 2 mol of THF as a solvent in an autoclave similar to Production Example 1, nitrogen atmosphere Half esterification was performed at 80 ± 10 ° C. for 2 hours. Thereafter, 2 mol of benzyl chloride was added as a raw material for R1, and reacted at 80 ± 10 ° C. for 6 hours. After the reaction, the precipitated salt was filtered off, the organic layer was washed with water, and the target product was extracted and separated with toluene. The organic layer was dried over anhydrous magnesium sulfate, and the solvent was distilled off at 80 ± 10 ° C. and 10 kPa to obtain a strength improver A1-4. The measured values of each strength improver are shown in Table 1.

The strength improvers A1-8 to 12 were each produced using the raw materials shown in Table 2 and the amounts used (moles) by the following production method. An example will be described in A1-8.
1 mol of polyol (IV) (Z constituent raw material), 1 mol of trimellitic anhydride (Y constituent raw material), 0.02 mol of N-ethylmorpholine as a catalyst, and 2 toluene as a solvent in an autoclave similar to Production Example 1. A half esterification was performed for 2 hours at 80 ± 10 ° C. in a nitrogen atmosphere. Thereafter, 2 mol of EO as the R1 constituent raw material was added dropwise over 2 hours while controlling to 80 ± 10 ° C. and 0.5 MPa or less, and aged for 3 hours. After aging, the catalyst and the solvent were distilled off at 80 ± 10 ° C. and 10 kPa to obtain a strength improver A1-8. The measured values of each strength improver are shown in Table 1.

The strength improvers A1-13 to 14 were produced using the raw materials shown in Table 2 and the amounts used (moles) by the following production method. An example will be described in A1-13.
1 mole of PEG-200 (Z constituent raw material), 1 mole of trimellitic anhydride (Y constituent raw material), catalyst in a reactor equipped with a stirring device, temperature control device, pressure control device, cooler, trap, and liquid circulation pump N-ethylmorpholine as 0.02 mol, toluene as a solvent was charged in 2 mol, and half esterification was performed at 80 ± 10 ° C. and 0.1 MPa in a nitrogen atmosphere for 2 hours. Thereafter, 2 mol of benzylamine was added as an R1 constituent raw material and reacted for 6 hours while controlling to 95 ± 5 ° C. and 0.06 MPa. During the reaction, volatile toluene and water were condensed with a cooler, and toluene separated by the trap was returned to the reactor again. After the reaction, the catalyst and the solvent were distilled off at 80 ± 10 ° C. and 10 kPa to obtain a strength improver A1-13. The measured values of each strength improver are shown in Table 1.

<Examples 1-66, Comparative Examples 1-3>
The raw materials of the semi-rigid polyurethane foams in Examples 1 to 66 and Comparative Examples 1 to 3 are the same as those shown in the above production examples, and the other items are as follows.

(1) Polyether polyol A2-1: Block adduct added to propylene glycol in the order of EO, PO, EO [hydroxyl value 28 (mg KOH / g, the same applies hereinafter), content of terminal EO unit = 10%, Content of internal EO unit 10%].
(2) Polyether polyol A2-2: a block adduct added to glycerin in the order of PO and EO (hydroxyl value 34, content of terminal EO unit = 14%).
(3) Polyether polyol A2-3: Block adduct added to glycerin in the order of PO and EO (hydroxyl value 36, content of terminal EO unit = 16%).
(4) Polyether polyol A2-4: Block adduct added to glycerin in the order of PO, EO, PO, and EO (hydroxyl value 28, content of terminal EO unit = 21%).
(5) Polymer polyol A2-5: Polymer polyol obtained by polymerizing acrylonitrile in polyether polyol A2-2 (polymer content: 20% by weight).
(6) Polymer polyol A2-6: A weight ratio of acrylonitrile and styrene (acrylonitrile) in a block adduct [hydroxyl value 28, content of terminal EO unit = 14%] added in the order of PO and EO to pentaerythritol. : Styrene) Polymer polyol polymerized 2: 1 (polymer content 30% by weight).

(7) Polyether polyol A3: Block adduct added to glycerin in the order of PO and EO (hydroxyl value 280, content of terminal EO unit = 10%).
(8) Polyether polyol A4: an adduct obtained by adding EO to glycerin (hydroxyl value 842).

(9) Catalyst C-1: N, N-dimethylaminopropyldipropanolamine [“UCAT2024” manufactured by San Apro Co., Ltd.]
(10) Catalyst C-2: Bis (N, N-dimethylamino-2-ethyl) ether [“DABCO BL-19” manufactured by Air Products Co., Ltd.]
(11) Catalyst C-3: Triethylenediamine [“TEDA” manufactured by Tosoh Corporation]
(12) Catalyst C-4: 1,8-diazabicyclo [5.4.0] undec-7-ene (13) Catalyst C-5: Dibutyltin dilaurate [“Neostan U-100” manufactured by Nitto Kasei Co., Ltd. ]

(14) Foaming agent D-1: water

(15) Crosslinking agent E-1: ["Kaorizer P-200" manufactured by Kao Corporation]
(16) Crosslinking agent E-2: ethylene glycol

(17) Isocyanate B-1: Modified MDI [“CEI-264” manufactured by Nippon Polyurethane Co., Ltd.]
(18) Isocyanate B-2: Urethane-modified MDI (NCO% = 21.5%)
(19) Isocyanate B-3: Modified IPDI (NCO% = 30.5%)

In Examples 1 to 22 and Comparative Example 1, a polyol composition, a catalyst, a polyisocyanate component, a foaming agent, and a crosslinking agent shown in Table 3 were mixed using a high-pressure foaming machine (MiniRIM machine manufactured by PEC), and 300 × 300 It was injection molded into a metal sealed mold of × 10 mm. The molding conditions are shown below.
<Molding conditions> Mold temperature: 35-40 ° C
Cure time: 60 seconds
Injection amount: 160g
Table 3 shows the measurement results of the physical properties of the obtained foams.

In Examples 23 to 44 and Comparative Example 2, a high-pressure foaming machine (MiniRIM machine manufactured by PEC Co.) was used, and the polyol composition, catalyst, polyisocyanate component, foaming agent and crosslinking agent shown in Table 4 were mixed, and 300 It was injection molded into a metal sealed mold of × 300 × 5 mm. The molding conditions are shown below.
<Molding conditions> Mold temperature: 68-72 ° C
Cure time: 70 seconds
Injection amount: 230g
Table 4 shows the measurement results of the physical property values of the obtained foams.

In Examples 45 to 66 and Comparative Example 3, a high-pressure foaming machine (MiniRIM machine manufactured by PEC) was used, and the polyol composition, catalyst, polyisocyanate component, foaming agent and crosslinking agent shown in Table 5 were mixed, and 300 It was injection molded into a metal sealed mold of × 300 × 5 mm. The molding conditions are shown below.
<Molding conditions> Mold temperature: 95-100 ° C
Cure time: 60 seconds
Injection amount: 460g
Table 5 shows the measurement results of the physical property values of the obtained foams.

表３〜５におけるフォーム物性の評価方法は下記の通りである。
見掛け密度（ｇ／ｃｍ³ ） ：ＪＩＳ Ｋ６４０１
Ｃ硬度 ：ショアーＣ硬度計により測定
Ａ硬度 ：ショアーＡ硬度計により測定
Ｄ硬度 ：ショアーＤ硬度計により測定
伸び率（％） ：ＪＩＳ Ｋ６４０１
引張強度（ＭＰａ） ：ＪＩＳ Ｋ６４０１
引裂強度（Ｎ／ｍｍ） ：ＪＩＳ Ｋ６４０１

The evaluation methods of foam physical properties in Tables 3 to 5 are as follows.
Apparent density (g / cm ³ ): JIS K6401
C hardness: measured with Shore C hardness meter A hardness: measured with Shore A hardness meter D hardness: measured with Shore D hardness meter Elongation rate (%): JIS K6401
Tensile strength (MPa): JIS K6401
Tear strength (N / mm): JIS K6401

  In Tables 3 to 5, the urethane foams of Examples 1 to 66 of the present invention have foam physical properties, particularly tensile strength, tear strength, and compression hardness, as compared with the urethane foams of Comparative Examples 1 to 3 obtained by the prior art. Are better.

  According to the method for producing a semi-rigid polyurethane foam of the present invention, it is possible to achieve both mechanical properties such as elongation and tensile strength and hardness as compared with the conventional method, such as an instrument panel, a steering wheel, etc. It is possible to increase the physical properties and weight of automobile interior materials.

Claims (5)

A method for producing a semi-rigid polyurethane foam by reacting a polyol component (A) and an organic polyisocyanate component (B) in the presence of a catalyst (C) and a foaming agent (D), wherein (A) is: A method for producing a semi-rigid polyurethane foam comprising a strength improver (A1) and a polyol (A2).
Strength improver (A1): Strength improver for producing polyurethane foam represented by the following general formula (I).

[In the general formula (I), R1 represents a residue obtained by removing one active hydrogen from an active hydrogen-containing compound. A plurality of R1 may be the same or different. ; Y represents the residue remove | excluding the carboxyl group from trivalent or more aromatic polycarboxylic acid (e). The aromatic ring of Y is composed of carbon atoms. The substituent of the aromatic ring may be a hydrogen atom or another substituent, but at least one substituent is a hydrogen atom. A is an integer satisfying 0 ≦ a ≦ (the number of aromatic ring substituents−2). B is an integer satisfying 0 ≦ b ≦ (the number of aromatic ring substituents−2). A + b is an integer satisfying 2 ≦ a + b ≦ (the number of aromatic ring substituents−2). Z represents a residue obtained by removing m active hydrogens from an active hydrogen-containing compound having a valence of at least m; M represents an integer of 1 to 10; ]
Polyol (A2): A polyether polyol other than (A1) having a number average functional group number of 2 to 4, a hydroxyl value of 20 to 150 mgKOH / g, and a content of terminal oxyethylene units of less than 30% by weight. The method for producing a semi-rigid polyurethane foam according to claim 1, wherein b in the general formula (I) is 0. The method for producing a semi-rigid polyurethane foam according to claim 1 or 2, wherein R1 and Z in the general formula (I) are different groups. The method for producing a semi-rigid polyurethane foam according to any one of claims 1 to 3, wherein the content of the strength improver (A1) is 1 to 99% by weight based on the weight of the polyol component (A). The method for producing a semi-rigid polyurethane foam according to any one of claims 1 to 4, wherein the content of the polyol (A2) is 1 to 99% by weight based on the weight of the polyol component (A).