JPH0291116A - Preparation of condensation type resin dispersion - Google Patents

Abstract

PURPOSE:To obtain a condensation type resin compsn. with good dispersion stability and low viscosity by depositing fine particles of a condensation resin of aldehydes from a dispersion medium and substituting an active hydrogen compd. for a solvent. CONSTITUTION:Condensation reaction of a compd. capable of condensing with aldehydes with one of aldehydes or a precondensate thereof is performed in a dispersion medium wherein water and or an org. solvent is the main component to deposit fine particles of a condensation resin which hardly sediment in this dispersion medium. Then, an aimed dispersion is obtd. by substituting an active hydrogen compd. having 2 or more active hydrogen groups reactive with an org. isocyanate compd. for the water and/or org. solvent. As regards the active hydrogen compd. to be used, it is pref. that the active hydrogen group be a hydroxyl, prim. amino and/or sec. amino group; the number of these active groups per molecule be 2 or larger; the MW per active hydrogen group be 100-4,000.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a condensed resin dispersion suitable for producing polyurethane.

[Prior Art] Conventionally, polyols for polyurethane raw materials, such as polymer polyols or graft polyols, have been known. This is an addition polymer grafted onto the molecular chain of a polyol such as a polyether polyol or an unsaturated polyol, or an addition polymer or other polymer is simply dispersed in the polyol. be. This type of polymer polyol can be produced by polymerizing a vinyl polymer such as acrylonitrile or styrene in a liquid polyol, by simply dispersing a pre-produced polymer such as a vinyl polymer in a polyol, or by simply dispersing a pre-produced polymer such as a vinyl polymer in a polyol. A method is known in which the resulting polymer is then grafted onto a polyol. In most cases, the polymer in such conventional polymer polyols is a nil polymer, but in exceptional cases, dispersed linear polyesters are also known.

It is also known to use an amino resin initial condensate as a polyurethane raw material. Since the amino resin initial condensate has a hydroxyl group that can react with isocyanate groups such as methylol groups, polyurethane foam etc. can be obtained by reacting this with a polyisocyanate compound (
JP-A No. 53-16798, etc.). Furthermore, it is also known that a mixture of an etherified amino resin initial condensate, in which a portion of the methylol groups of the amino resin initial condensate is etherified, and a normal polyol for polyurethane raw materials can be used as a raw material for producing polyurethane foam ( Japanese Unexamined Patent Publication No. 52-15
(Japanese Unexamined Patent Publication No. 101848/1982), a method of producing the amino resin by condensing the initial condensate of such an amino resin in a polyol has also been proposed (Japanese Patent Application Laid-open No. 101848/1984).

[Problems to be Solved by the Invention] There are still various problems with the conventional polyurethane raw materials described above. First, so-called polymer polyols are suitable as raw materials for high-modulus polyurethane foams, but they have an unresolved problem in that they are not effective in making polyurethane flame retardant, but actually reduce the flame retardancy. There is also.

On the other hand, amino resin initial condensate-containing polyols are polyols in which the amino resin initial condensate is a polyol with a relatively low molecular weight, and does not have a high molecular weight as the polymer in the above-mentioned polymer polyols. Because it is difficult to exhibit the effect of increasing elasticity and its use is limited to rigid polyurethane foam, it is difficult to recognize it as a type of polymer polyol.

On the other hand, there is also a known method of making polyurethane flame retardant by filling polyurethane with a crosslinked high molecular weight condensation resin powder as a filler, but it is difficult to stably disperse such a filler in a polyol. The dispersion stability is inferior to that of so-called polymer polyols, which is disadvantageous in the production of polyurethane.

Furthermore, Japanese Patent Publication No. 57-14708 proposes a method for producing a dispersion of an aminoplast condensate by condensing a substance capable of forming an aminoplast in a polyhydroxy compound. However, a completely stable dispersion of resin particles could not be obtained, and only resin particles with a high particle size could be obtained.

Furthermore, Japanese Patent Application Laid-open No. 122193/1983 describes a method of forming sedimentary particles and blending them with polyol or the like. However, in this case, the particle size is large and tends to settle in the polyol. In order to improve the dispersion stability of such condensed resin particles, it is necessary to reduce the particle size, but on the other hand, when the particle size is reduced, there is a problem that sedimentation becomes difficult and filtration separation becomes difficult.

The present invention solves the various problems with polyols containing conventional polymers as raw materials for polyurethane as described above, and can be used as a raw material for producing flame-retardant polyurethane, and has good dispersion stability and low The object of the present invention is to provide a new method for producing a viscous condensation resin dispersion.

[Means and effects for solving the problem] The present inventors have conducted various studies on condensed resin dispersions with good dispersion stability and low viscosity.

A dispersion in which the condensation resin is sufficiently crosslinked rather than an initial condensate, and is dispersed in a legal hydrogen compound having two or more active hydrogen groups that are reactive with a cyncyanate compound such as a polyol. Polyurethane foam with excellent flame retardancy can be obtained by using this as a polyurethane raw material, and there is no conventional method for condensing such a dispersion in a polyol.

It can be manufactured by a method of first performing a condensation reaction in water and/or an organic solvent to obtain condensed resin particles, and then replacing the dispersion medium of water and/or organic solvent with a legal hydrogen compound such as a polyol. I found out.

That is, the present invention involves a condensation reaction between a compound that can be condensed with an aldehyde and an aldehyde or an initial condensate thereof in a dispersion medium mainly composed of water and/or an organic solvent. After precipitating condensation resin particles, the water and/or organic solvent is replaced with a legal hydrogen compound having two or more active hydrogen-containing groups capable of reacting with an organic isocyanate compound. This is a method for producing a resin dispersion.

In the present invention, compounds that can be condensed with aldehydes (
(hereinafter also referred to as aldehyde condensation compound) and aldehydes are first reacted in a dispersion medium consisting of water and/or an organic solvent to produce a condensation resin, but at this time most of the condensation reaction is completed. is sufficiently reacted to obtain a dispersion in which three-dimensionally crosslinked condensed resin particles insoluble in the solvent are precipitated and dispersed using the dispersion medium as a dispersion medium,
Next, a legal hydrogen compound (hereinafter also referred to as legal hydrogen compound) having two or more active hydrogen-containing groups that can react with the organic isocyanate compound is added, and water and/or the organic solvent are removed by heating and/or reduced pressure. By replacing the dispersion medium, a condensed resin dispersion using the legal hydrogen compound as a dispersion medium is obtained.

One of the raw materials for forming the condensation resin according to the present invention is aldehydes. As the aldehydes, aliphatic, alicyclic, aromatic, and heterocyclic aldehyde compounds, other aldehydes, condensates thereof, and derivatives such as compounds capable of generating aldehydes can be used alone or in combination. Preferred aldehydes are lower aliphatic aldehydes, particularly preferably aliphatic aldehydes having 4 carbon atoms or less, and derivatives thereof, such as formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, paraformaldehyde, paraacetaldehyde, and the like. , preferably formaldehyde. These aldehydes can also be used dissolved in a solvent,
A particularly preferred solvent is water, but is not limited thereto. In the present invention, it is particularly preferred to use an aqueous solution of formaldehyde, ie formalin.

Other raw materials for forming condensation resins are compounds that can be condensed with aldehydes to form solid condensation resins (hereinafter referred to as aldehyde condensation compounds), which are located at positions where they can react with aldehydes (hereinafter referred to as 1). Basically, two reaction sites are required. The reactive site is typically a carbon atom to which hydrogen is bonded in an aromatic group, or a nitrogen atom to which hydrogen is bonded to an amino group or an amide group.

The aromatic reaction site is particularly preferably an aromatic ortho-position or para-position to which a hydroxyl group or an amino group is bonded, and has two or more such reaction sites. In other words, compounds having no substituent at this site are suitable, and as compounds having amino groups or amide groups, basically polyamine compounds having two or more of these groups are suitable.

Therefore, as the aldehyde condensing compound, aromatic compounds such as phenols and aromatic amines, and polyamine compounds such as urea and guanidine compounds are preferable. Two or more kinds of compounds capable of reacting with these aldehydes can be used in combination, and a compound having only one reactive site can also be used together with these compounds.

Among the aromatic compounds mentioned above, phenols include, for example, phenol, cresol, xylenol, P-alkyl, phenol, P-phenylphenol, bisphenol A, resorcinol, etc. Particularly preferred is phenol; Examples of amines include aniline, diaminobenzene, P-alkylaniline, N-substituted alkylaniline, diphenylamine, and diaminodiphenylmethane, and like the phenolic compounds, they can be used alone or in combination of two or more.

Since the amino group or amide group of an aromatic amine is itself a reactive site, it may be considered as one of the following diamine compounds; There may be one reactive site,
A particularly preferred aromatic amine is aniline. The aromatic compounds are not limited to the above compounds.

Aromatic hydrocarbons and other compounds such as benzene and xylene can also be used. Furthermore, phenols and aromatic amines can be used in combination, or at least one of them can be combined with another aromatic compound.

As the polyamine compound, compounds having basically two or more amino groups or amide groups are preferred, especially compounds having two or more amino groups, such as urea, thiourea, N
- Ureas such as substituted urea, melamine compounds such as melamine, N-alkyl substituted melamine, S-triazines having two or more amino groups such as guanamine compounds such as benzoguanamine and acetoguanamine, guanidine, guanidine hydrochloride, hydrochloric acid Guanidines such as aminoguanidine and dicyandiamide are preferred, and among these, urea, melamine, and benzoguanamine are particularly preferred.These polyamine compounds can be used in combination of two or more, for example, urea-
Thiourea, urea-melamine, urea-benzoguanamine,
Combinations such as urea-melamine-benzoguanamine and melamine-dicyandiamide can also be used.

Moreover, the above-mentioned polyamine compound and the above-mentioned aromatic compound can be used in combination, such as phenol-urea, phenol-melamine, aniline-urea.

Examples include aniline-melamine, phenol-aniline-melamine, phenol-urea-melamine, and other combinations.

Further, as the aldehyde condensing compound, in addition to the above, ketone compounds known as raw materials for ketone resins may also be used.

In addition, the above-described compounds having at least two reactive sites with aldehydes include compounds with one reactive site, and compounds that are not themselves aldehyde condensing compounds but have two or more active reactive sites. It can also be used in combination with compounds such as dialkanolamines, monoalkanolamines, aliphatic amines, etc.

Further, in the present invention, initial condensates of aldehyde condensing compounds and aldehydes, such as dimethylol urea, hexamethylolmelamine, hexamethoxydimethylmelanine, etc., can also be used as forming raw materials.

In the reaction for producing condensed resin particles, the ratio of the aldehyde condensable compound to the aldehyde is not particularly limited as long as the ratio includes the ratio at which the condensed resin is theoretically produced. Even if an unreacted aldehyde condensing compound remains, it may be contained in the produced dispersion as long as the amount is not excessive, and the unreacted aldehyde will be removed when the dispersion medium is replaced. Preferably, aldehyde condensing compound 10
5 to 500 parts by weight, especially 10 to 100 parts by weight of aldehydes are used per 0 parts by weight.

The condensation resin produced by this reaction is thought to be similar to or the same as the cured products of conventionally known condensation thermosetting resins such as phenol resins, urea resins, and melamine resins, and the production reaction is also similar. It is thought that. For example, when formaldehyde is used as the aldehyde, the aldehyde condensable compound and formaldehyde undergo addition condensation in the initial stage of the reaction, thereby producing various methylol group-containing compounds. The above-mentioned initial condensate, which is one of the forming raw materials of the present invention, corresponds to the methylol addition compound at this stage. After this, the methylol group-containing compound undergoes dehydration condensation, so that the methylol group becomes a methylene group, which is condensed to form a three-dimensionally crosslinked condensation resin that is insoluble and infusible in the solvent.

Water and/or an organic solvent is used as a dispersion medium when carrying out this condensation reaction. Since this dispersion medium is later replaced with an oil-containing hydrogen compound, it is preferable to use a dispersion medium that can be removed by means such as heating and/or reduced pressure. Preferably 250
°C, in particular using a dispersion medium with a boiling point below 180 °C, but with a dispersion medium that vaporizes under reduced pressure below 250 °C, especially below 180 °C, under heating, under reduced pressure, or more preferably under heating and reduced pressure. Use a dispersion medium that can be removed below.

As such a dispersion medium, for example, in addition to water, aliphatic hydrocarbons such as pentane, hexane, cyclohexane, and hexene, aromatic hydrocarbons such as benzene, toluene, and xylene,
Alcohols such as methanol, ethanol, isopropanol, butanol, cyclohexanol, benzyl alcohol, ethers such as isopropyl ether, tetrahydrofuran, benzyl ethyl ether, acetal, anizole, ketones such as acetone, methyl ethyl ketone, acetophenone, ethyl acetate, Esters such as butyl acetate, halogenated hydrocarbons such as chlorobenzene, chloroform, dichloroethane, 1,1,2-trichlorotrifluoroethane, nitro compounds such as nitrobenzene, nitriles such as acetonitrile, benzonitrile, triethylamine, triethylamine, butylamine,
Solvents include amines such as dimethylaniline, amides such as N,N-dimethylformamide and N-methylpyrrolidone, and sulfur compounds such as dimethyl sulfoxide and sulfolane.In the present invention, these dispersion media are used alone or in combination. can.

Note that the legal hydrogen compound described below is a compound that usually has an extremely high boiling point, but has virtually no boiling point (it decomposes without becoming a gas when heated). Even if it has a boiling point, the boiling point usually exceeds 250°C. Even if the oil-containing hydrogen compound has a boiling point of 250°C or lower, it is preferable that it has a boiling point of at least 20°C, preferably 50°C or higher than the boiling point of the dispersion medium used. For example, when using an oil-containing hydrogen compound having such a relatively low boiling point, it is preferable to use a dispersion medium having a boiling point lower than the boiling point by 20"C or more, preferably 50"C or more.

Aldehyde condensation compounds and aldehydes or their initial condensation products can be reacted as they are in an organic solvent, but since they are highly compatible with water in the initial condensation state, it is best to use water and an organic solvent together. preferable. When the aldehyde condensation compound, aldehydes, or their initial condensation products have affinity with the organic solvent, the initial condensation reaction proceeds uniformly, and condensation resin particles are then precipitated. In addition, if there is no affinity with the organic solvent, the reaction proceeds in an emulsified state from the initial condensation reaction stage, and condensed resin particles are precipitated as it is.

The present invention is a method characterized in that the condensation resin production reaction is basically completed before replacing the dispersion medium with the oil-containing hydrogen compound. Whether or not it has been sufficiently crosslinked,
This can be determined from the fact that the methylol group produced at the beginning of the reaction is converted to a methylene group, resulting in a decrease in the hydroxyl value. In other words, to explain the example of dispersion medium replacement using a polyol as an oil-containing hydrogen compound, when comparing the hydroxyl value of the polyol and the resulting dispersion, if the hydroxyl value of the dispersion increases, it is likely that crosslinking is occurring. It is thought that the presence of methylol groups is due to insufficient crosslinking, and if the hydroxyl value is the same or lower, it is considered that sufficient crosslinking has occurred.

The particle diameter of the fully crosslinked condensed resin particles of the present invention is 0.
It is preferably within the range of O1 to 5JL, particularly preferably 0.
It is within the range of 1 to 2 IL. If it exceeds 5#L, it tends to settle in legal hydrogen compounds such as polyols. The particles may settle easily or within a relatively short time in the dispersion medium. However, it is preferable that the particles do not easily settle even in the dispersion medium, that is, it is preferable that the precipitated condensed resin particles do not substantially settle in the dispersion medium until the next dispersion medium replacement. In particular, it is preferable that the condensed resin particles do not settle for one day or more when left still, and after replacing the dispersion medium, the condensed resin particles will remain stable for at least one month, preferably two months or more, after replacing the dispersion medium. Preferably, it does not precipitate.

Below, the process of obtaining this condensable resin compound will be explained in more detail. The aldehyde condensing compound and aldehydes react at room temperature to heating and/or under pressure. It is thought that at relatively low temperatures, methylol group-containing compounds and low molecular weight condensates with aldehydes added are likely to be formed, and at relatively high temperatures, methylene crosslinks and dimethylene ether bonds due to dehydration reactions of methylol groups, etc. are likely to be formed. It will be done. Of course, the compounds produced are not related only to the reaction temperature, but vary depending on the charging ratio of each structural unit, the presence of additives such as catalysts, etc.

However, considering only the reaction temperature, in the present invention, it is preferable to conduct the reaction at a relatively low temperature in the first stage of the reaction and at a relatively high temperature in the second stage of the reaction.

In particular, a relatively high temperature in the latter stage of the reaction is often necessary for the condensation reaction of hydroxyalkyl groups such as methylol groups to occur. At a high temperature of about 10°C and about 6
The upper limit temperature in the latter stage of the 0 reaction, which is preferably carried out at a temperature of 0°C or higher, is preferably a temperature at which side reactions other than the decomposition of the oil-containing hydrogen compound and the formation reaction of the condensation resin are difficult to occur. When used as a solvent, the temperature is particularly preferably 80 to 150°C under normal pressure, and the temperature is preferably about 80 to 200°C in the case of an organic solvent or a coexistence system of water and an organic solvent.

In order to allow the condensation reaction to proceed at relatively low temperatures, acids such as hydrochloric acid and acetic acid, and bases such as NaOH and )ethylamine can also be used as catalysts. In addition, in order to increase the stability of the condensation resin particles, 100 parts by weight or less of an oil-containing hydrogen compound, such as a polyol or an amino polyol, which is to be replaced with a dispersion medium later during the condensation reaction, is added to 100 parts by weight of the 11-condensation resin. It is also effective to keep it. Furthermore, the reaction can be carried out in the presence of various additives such as a curing agent, a dispersion stabilizer such as hexamethylenetetramine, and a coloring agent.

It is not preferable that the oil-containing hydrogen compound used as a raw material for polyurethane contains a relatively large amount of water. Therefore,
Water initially used as a solvent or dispersion medium needs to be removed when it is replaced with the polyol. Water can usually be removed by heating or under reduced pressure. Further, organic solvents used as solvents and dispersion media can also be removed by heating at 250° C. or lower and/or under reduced pressure. Therefore, by adding an oil-containing hydrogen compound to a dispersion containing water and/or an organic solvent as a dispersion medium in which condensation resin particles are precipitated, and removing the water and/or organic solvent under heating and/or reduced pressure, The dispersion medium is replaced with an oil-containing hydrogen compound.

The present invention is characterized in that most of the condensation reaction is completed before the dispersion medium is replaced, but when water is removed, some unreacted condensation may occur and be dehydrated.

In the oil-containing hydrogen compound according to the present invention, the active hydrogen-containing group is a hydroxyl group, a -grade amino group, and/or a secondary amino group, and at least 2 active hydrogen-containing groups per molecule.
or more, preferably 2 to 8, and the molecular weight per active hydrogen-containing group is 100 to 4,000. Preferably 200-3
000, particularly preferably from 400 to 2,500, such as polyether polyols, polyester polyols, hydrocarbon polymers having a hydroxyl group at the end, and so-called polymer polyols.
Particularly preferred are polyether polyols. Examples of compounds having amino groups include polyether polyols, aminated polyethers in which part or all of the OH groups of polyester polyols are substituted with primary or secondary amino groups, and mixtures thereof.

Examples of polyether polyols include polyether polyols obtained by adding alkylenoxide to polyhydroxy compounds such as polyhydric alcohols, amines, active hydrogen-containing compounds such as phosphoric acid, and polyether polyols made of cyclic ether polymers.

Specifically, glycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol, dextrose, sucrose, other polyhydric alcohols, jetanolamine, triethanolamine and other alkanolamines, bisphenol A, phenol-
Polyether polyols made by adding ethylene oxide, propylene oxide, butylenoxide, epichlorohydrin and other alkylene oxides, and epoxides such as styrene oxide and glycidyl ether to formaldehyde condensates, other polyhydric phenols, ethylenediamine, diaminodiphenylmethane, and other amines. and polyether polyols such as tetrahydrofuran polymers. Two or more of these can also be used in combination. Preferred polyether polyols are polyether polyols having a molecular weight per OH group of 300 to 2,500, particularly those having a molecular weight of 600 to 2,000 per OH group,
Polyether polyols having 2 to 8 hydroxyl groups are preferred.

As the aminated polyether, it is possible to use one obtained by aminating a polyether polyol with ammonia, or one obtained by hydrolyzing an isocyanate group-containing prepolymer obtained by reacting a polyether polyol and a polyisocyanate. Although it is possible, the former is particularly preferred.

In addition, esters containing hydroxyl groups such as polyhydric alcohols, polyhydroxy esters, etc., which are of the same type as the above-mentioned self-active hydrogen compounds but have a lower molecular weight than those mentioned above, are used, and the polyhydric alcohols include the above-mentioned polyethers and polyesters. Among those that can be used as initiators for polyether polyols, liquid ones can also be used.

The amount of the condensation resin dispersed in the self-active hydrogen compound in the dispersion of the present invention is not particularly limited as long as the condensation resin is stably dispersed, but if it becomes excessive, the dispersion stability will decrease and the viscosity will increase. Therefore, in normal cases, the legal hydrogen compound 1
The amount of the condensed resin is preferably 200 parts by weight or less, particularly preferably 100 parts by weight or less, based on 00 parts by weight. Although there is no particular lower limit, in order to exhibit the effect of the dispersion of the present invention in producing polyurethane, it is preferable that the condensation resin is present in an amount of at least about 5 parts by weight per 100 parts by weight of the legal hydrogen compound.

The solid condensation resin dispersion of the present invention obtained in the above manner is preferably a white to colored translucent to opaque viscous liquid in which condensation resin particles having a particle size of 0.1 to 5 μl are dispersed, and the viscosity is as low as that used. Although it varies depending on the viscosity of the self-active hydrogen compound, the proportion of the condensed resin in the dispersion, the type of condensed resin, etc., it is suitable for use as a polyurethane raw material to normally have a viscosity of 50,000 cps or less at 25°C.

Even if the viscosity is higher than this, it may of course be possible to use it by diluting it with another self-active hydrogen compound.

In the dispersion of Completion I51, most of the condensed resin is considered to be dispersed in the oil-containing hydrogen compound. In the method of the present invention, the condensation reaction is almost completed in water and/or an organic solvent, and the condensation reaction does not proceed any further in the oil-containing hydrogen compound after the dispersion medium has been replaced. It can be considered that the grafting of 2 to the self-active hydrogen compound basically does not occur. However, if a portion of a self-active hydrogen compound is added to water and/or an organic solvent to improve dispersibility and a condensation reaction is carried out, there is a possibility that grafting may occur.

In the present invention, in the case of a dispersion using an oil-containing hydrogen compound containing an aromatic nucleus, an amino group, or an amide group, a particularly good dispersion state can be obtained because it has good affinity with the condensation resin.

It is preferable that the integrated resin dispersion according to the present invention does not undergo separation for at least about one month, particularly for at least two months in a stationary state, but of course it is not limited to this time. The reason why the product of the present invention has such excellent dispersion stability is presumed to be that the condensed resin fine particles have a fine and uniform diameter.

The hydroxyl value of the condensed resin dispersion of the present invention is mainly related to the hydroxyl group of the oil-containing hydrogen compound. In the present invention, the hydroxyl value of the oil-containing hydrogen compound is usually preferably 800 or less,
In particular, in the case of a high molecular weight polyol having a molecular weight of 300 to 2,500 per hydroxyl group, the hydroxyl value is about 22 to 190.

As mentioned above, in the dispersion of the present invention, the condensation resin is sufficiently crosslinked, so it has almost no functional groups containing hydroxyl groups such as methylol groups, so the hydroxyl value of one dispersion is Compared to that of the oil-containing hydrogen compound used as a medium, the hydroxyl value does not become significantly higher, and it decreases compared to the oil-containing hydrogen compound in proportion to the content of the condensation resin.
The hydroxyl group of the dispersion is preferably 1.2 times or less, particularly equal to or less than that of the oil-containing hydrogen compound.

However, when a hydroxyl group-containing compound such as a phenol compound is used as the aldehyde condensing compound, the hydroxyl value of the dispersion may be higher than the hydroxyl value of the oil-containing hydrogen compound.

In addition, in the case of a known polyol containing an amino resin initial condensate, if the hydroxyl value of the polyol used is higher than that of the amino resin initial condensate, the hydroxyl value of the dispersion polyol will be lower than that of the original polyol. When urea or polymethylolmelamine, which has a high hydroxyl value of about 600 or more, is used as a component of the amino resin initial condensate, a polyol with a low hydroxyl value (i.e., high molecular weight) is used to form a dispersion. has a hydroxyl value significantly higher than the hydroxyl value of the polyol.

The condensed resin dispersion of the present invention obtained by the production method described above is particularly suitable for use as part or all of the oil-containing hydrogen compound as the main raw material in polyurethane production. Further, the condensed resin dispersion of the present invention containing a relatively low molecular weight oil-containing hydrogen compound can be used as part or all of a crosslinking agent that is an auxiliary raw material for polyurethane.

While conventional polymer polyols actually lowered the flame retardancy of polyurethane, the condensation resin of the present invention improves the flame retardance of polyurethane. In particular, the condensation resin dispersion of the present invention, which mainly uses a phenol compound, a urea compound, a melamine compound, a guanamine compound, or a quanidine compound, is particularly effective in improving the flame retardance of polyurethane.

Therefore, the present invention also relates to the use of a condensed resin dispersion, in which polyurethane is produced using an oil-containing hydrogen compound and a polyisocyanate compound containing two or more active hydrogen groups capable of reacting with an organic isocyanate compound. The present invention provides a method for producing polyurethane, characterized in that the condensed resin dispersion of the present invention is used as part or all of the oil-containing hydrogen compound. The polyol used as the basic raw material for polyurethane has a molecular weight of 300 to 300 per hydroxyl group in the membrane.
0 high molecular weight polyol, # is a polyether polyol with a molecular weight of 600 to 2,500 and 2 to 8 hydroxyl groups in the molecule, and polyols with a lower molecular weight than the above are used for rigid polyurethane foam. ing. Therefore, when the condensed resin dispersion of the present invention is used as part of the raw material for polyurethane, the above-mentioned conventionally used high molecular weight polyols are suitable as other polyols to be used in combination.

In the production of polyurethane, a crosslinking agent consisting of a relatively low molecular weight active hydrogen-containing compound containing two or more active hydrogens such as polyhydric alcohol, alkanolamine, polyamine, etc. is used in addition to the basic raw materials of polyol and polyisocyanate compound. There are cases. The condensed resin dispersion, particularly the condensed resin dispersion obtained using a low molecular weight polyol, can be used as part or all of the crosslinking agent.

As the polyurethane in the present invention, polyurethane foam is most suitable. The condensation resin dispersion of the present invention can be used in the same manner as conventional polymer polyols to obtain polyurethane foams with high sex appeal. The use of blowing agents is usually necessary in the production of polyurethane foams. As the blowing agent, water, trichlorodifluoromethane, dichlorodifluoromethane, methylene chloride, and other halogenated hydrocarbons are used. A further component often required in the production of polyurethane foams is a foam stabilizer. As the foam stabilizer, poly(dialkylsilane), polyoxyalkylene chain-containing silane, and other organosilicon compounds are suitable, but fluorosurfactants may also be used. Catalysts are commonly used in the production of foam or non-foam polyurethanes. As the catalyst, various tertiary amines, other amine compounds, organic tin compounds, etc. are used alone or in combination. In addition, various additives such as stabilizers, filler 1 reinforcing agents, colorants, mold release agents, crosslinking agents, chain extenders, and flame retardants can be used as raw materials for the foam or non-foam polyurethane.

Other basic raw materials for polyurethanes are polyisocyanate compounds. As the polyisocyanate compound, aromatic, aliphatic, alicyclic, heterocyclic, etc. compounds having at least two isocyanate groups can be used alone or in combination, and aromatic polyisocyanates are particularly preferred. Preference is given to using compounds. If specific polyisocyanate compounds are listed, for example, tolylene diisocyanate (TD
I), diphenylmethane isocyanate (MDI), polymethylene polyphenylisocyanate, xylylene diisocyanate, naphthalene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and the like. The polyisocyanate compound can also be used as a modified polyisocyanate compound modified by various methods or compounds, and can also be used as a blocked isocyanate compound blocked with various compounds. The method for producing polyurethane using these raw materials is not particularly limited, and includes, for example, the one-shot method and the prepolymer method.

A method such as the RIM method can be used.

Although the mechanism of action by which a condensed resin dispersion with good dispersion stability and low viscosity is obtained in the present invention is not necessarily clear, it is important to note that the liI composite resin particles are fine and uniform, and that polyol is basically It can be assumed that this is because there are many particles that do not react and exist independently.

[Example] The present invention will be specifically explained below with reference to Examples, in which parts in each example mean parts by weight. Note that the present invention is not limited to these Examples.

Example 1 50 parts of melamine, 35% formaldehyde aqueous solution [24.5 parts of formaldehyde, water (not including by-product water) 45.
5 parts (37.9 parts by weight of the total system)] was charged into a reactor, and after adding 2 parts of 0.5 N-HCl, the mixture was heated at 60°C.
After stirring was continued for 1 hour, the reaction was further carried out at 100°C for 2 hours. The system became cloudy during the process, and a stable aqueous suspension in which fine particles were dispersed was obtained. This suspension has a molecular weight of 500
150 parts of polyoxyethylene propylene triol having a concentration of 0.0 was added thereto, and the water in the system was removed under reduced pressure at 100°C to obtain a white viscous emulsion. Hydroxyl value is 25.0, viscosity is 2
It was 100 cp (25°C). It was found that the solid particles in this polyol were stably dispersed for more than two months without separating from the polyol at all.

Comparative Example 1 In a system in which polyoxyethylene propylene triol was simultaneously charged and reacted with melamine and formaldehyde aqueous solutions with the same composition as in Example 1, a similar white dispersion was obtained, but the viscosity of this was 3500 cp (25°C). it was high.

Example 2 50 parts of urea, 30 parts of dicyandiamide, 150 parts of 35% formaldehyde aqueous solution, [formaldehyde 52.5 parts]
parts, water (not including by-product water) 97.5 parts (37.5 parts of the total system)
% by weight)] 30 parts of polyoxyethylene propylene triol having a molecular weight of 3000 was charged into a reactor and reacted at 80°C for 5 hours and then at 100°C for 3 hours. The system became cloudy during the process, and an aqueous suspension in which fine particles were dispersed was obtained. 90 parts of polyoxyethylene propylene triol having a molecular weight of 3000 was added to this suspension, and the water in the system was removed under reduced pressure at 100°C to obtain a white viscous emulsion. This product had a hydroxyl value of 30.8 and a viscosity of 4800 cp (at 25°C). It was found that the solid particles in this polyol were stably dispersed without separating from the polyol for more than two months.

Example 3 50 parts of dimethylol urea, 100 parts of water, 0.5N-)I
Two parts of CI were charged into a reactor and reacted at 100° C. for 3 hours. The system became cloudy during the process, and an aqueous suspension in which fine particles were dispersed was obtained. 100 parts of polyoxyethylene propylene triol using a sorbitol initiator having a molecular weight of 6000 was added to this suspension, and the wood in the system was removed under reduced pressure at 100°C to obtain a white viscous emulsion. This product had a hydroxyl value of 38.3 and a viscosity of 3200 cp (25°C). It was found that the solid particles in this polyol were stably dispersed without separating from the polyol for more than two months.

Example 4 30 parts of urea, 20 parts of melamine, 50 parts of a 35% formaldehyde aqueous solution, and 80 parts of toluene were charged into a reactor.
After adding 2 parts of 5N-)ICI, at 60°C for 1 hour,
The reaction was further carried out at 100°C for 2 hours. The system became cloudy during the process and a fine particle dispersion was obtained. In this dispersion, molecules i 30
00 polyoxyethylene propylene triol 150
The water and toluene in the system were removed under reduced pressure at 100°C to obtain a white viscous emulsion. This product had a hydroxyl value of 41.5 and a viscosity of 1980 cp (25°C). It was found that the solid particles in this polyol were stably dispersed for more than two months without separating from the polyol at all.

Comparative Example 2 In a system in which polyoxyethylene propylene triol was simultaneously charged and reacted with an aqueous solution of urea, melamine, and formaldehyde with the same composition as in Example 4, a white emulsion similar to that in Example 4 was obtained, but the viscosity is 2800cp (25°C
) was high.

Example 5 50 parts of melamine, 30 parts of dicyanamide, 150 parts of 35% formaldehyde aqueous solution, 30 parts of molecule z 5ooo polyoxy-engineered tyrene propylene triol, and N,N'-
Charge 300 parts of dimethylformamide into a reactor,
The reaction was carried out at 100°C for 5 hours and at 100°C for 3 hours. The system became cloudy during the process, and a fine particle dispersion was obtained. In this dispersion, molecule z
90 parts of polyoxyethylene propylene triol (500 g) were added, and water and N,N-dimethylformamide in the system were removed under reduced pressure at 100°C to obtain a white viscous emulsion. The hydroxyl value of this product is 20.0, and the viscosity is 5100.
cp (25°C). It was found that the solid particles in this polyol were stably dispersed without separating from the polyol for more than two months.

Example 6 50 parts of hexamethylenetetramine, 20 parts of water, 50 parts of methyl isobutyl ketone, and 2 parts of 0.5N hydrochloric acid were charged into a reactor and reacted at 100° C. for 3 hours.

The system became cloudy during the process, and a fine particle dispersion was obtained.

100 parts of polyoxyethylene propylene triol using a sorbitol initiator having a molecular weight of 6,000 was added to this dispersion, and water and methyl isobutyl ketone in the system were removed under reduced pressure to obtain a white viscous emulsion. This product had a hydroxyl value of 39.5 and a viscosity of 1100 cp (25°C). It was found that the solid particles in this polyol were stably dispersed without separating from the polyol for more than two months.

[Effects of the Invention] The present invention relates to a method for producing a polyol composition in which particles of an aldehyde condensation resin are dispersed in a polyol, in which the condensation reaction is first allowed to proceed in water and/or an organic solvent medium to form fine particles. By replacing the dispersion medium with an active hydrogen compound after precipitation, a condensed resin dispersion with low viscosity and excellent particle dispersion stability can be obtained.

Agent (Benshinshichi) Heiyi■+11shi

Claims (7)

[Claims] (1) A compound that can be condensed with aldehydes and an aldehyde or an initial condensate thereof are subjected to a condensation reaction in a dispersion medium mainly composed of water and/or an organic solvent to form fine particles that do not easily settle in the dispersion medium. After precipitating condensation resin particles, the water and/or organic solvent is replaced with an active hydrogen-containing compound having two or more active hydrogen-containing groups capable of reacting with an organic isocyanate compound. Method for producing dispersion. (2) The method according to claim 1, wherein the active hydrogen-containing compound is added after the aldehyde condensation resin is precipitated, and then water and the organic solvent are removed by vaporization. (3) The method according to claim 2, wherein the method of vaporizing and removing water and the organic solvent is a method of vaporizing and removing under heating and/or reduced pressure. (4) The method according to claim 1, wherein the dispersion medium mainly composed of water and/or an organic solvent contains a small amount of an active hydrogen compound. (5) The method according to claim 1, wherein the active hydrogen-containing compound has a boiling point or decomposition point higher than the boiling point of the water and/or organic solvent used. (6) The active hydrogen-containing compound has 2 to 8 hydroxyl groups and/or amino groups, and the molecular weight per active hydrogen-containing group is 10
2. Method according to claim 1, characterized in that it is between 0 and 4000. (7) The method according to claim 5, wherein the active hydrogen-containing compound is a polyether polyol.