JP7024417B2 - Fine particle consolidation method - Google Patents

Description

The present invention relates to an injectable drug solution composition for adhering fine particles such as sand to each other and effectively increasing the strength of the consolidated body.

Organic or inorganic injection chemicals are widely used to stabilize fine particles such as sand by adhesion. This chemical solution is generally an inorganic system called water glass, which is mainly composed of a silicate aqueous solution, or an organic system, which is a combination of a silicate aqueous solution and a polyisocyanate.
Compared to inorganic type, organic type has excellent curing speed and strength of cured product, and it cures even in the presence of water. However, the viscosity of polyisocyanate is higher than that of aqueous silicate solution, especially. In the cold season and cold regions, there is a problem that it is difficult to inject between fine particles having small voids. Further, in the mixing of the hydrophilic aqueous silicate solution and the hydrophobic polyisocyanate, there is a problem that the mixing failure due to the low compatibility often occurs and the strength is partially lowered. Under such circumstances, even in a low temperature environment, while having permeability to fine particles having narrow voids similar to that of water glass, the curing speed and the strength of the cured product comparable to those of an organic system are exhibited, and problems such as poor mixing occur. There was a need for a new organic injection.

As a method for solving these problems, Patent Document 1 describes a ground stabilization method using (a) a main agent in which an inert diluent is mixed with a hydrophilic urethane prepolymer containing a terminal isocyanate group, and (b) a dilute silicate aqueous solution. Is described.

This technology aims to improve the permeability by lowering the viscosity of the chemical solution and improve the storage stability of the chemical solution. Reactive diluents such as low molecular weight dibasic acid diester and alkylene carbonate, chlorinated paraffin, dioctylphthalate, dibutylphthalate, etc. It is stated that a plasticizer such as dioctyl adipate and an inactive diluent such as methyl ethyl ketone, toluene, xylene, 1,1,1-trichlorethane and the like (diluent containing no active hydrogen in the molecule) can be used in combination.

However, although the use of a diluent or a plasticizer has a great effect on reducing the viscosity of the injected drug solution, there is a concern that the diluent or the plasticizer may elute from the solidified body over time, and the environmental compatibility is low.

Special Publication No. 62-21039

The present invention has been made in view of the above circumstances. That is, an object of the present invention is to provide an injectable drug solution composition that can penetrate even between fine particles having narrow voids such as sand without using a diluent, a plasticizer, or the like, and fine particles using the same. It is an object of the present invention to provide a method for producing a fine particle solidified body, which can obtain sufficient strength when solidified and can improve water pollution (COD value) due to elution of an injectable drug solution composition.

As a result of repeated studies, the present inventor has injected an emulsion containing an emulsion of an isocyanate group-terminated prepolymer (D), which is a reaction product of an organic polyisocyanate (A) and an active hydrogen group-containing surfactant (B). We have found a chemical composition and have completed the present invention.

That is, the present invention includes the following embodiments.

(1) An injectable drug solution composition containing a water emulsion of an isocyanate group-terminated prepolymer (D), wherein the isocyanate group-terminated prepolymer (D) is an organic polyisocyanate (A) and an active hydrogen group-containing surfactant. An injectable drug solution composition, which is a reaction product with (B).

(2) The isocyanate group-terminated prepolymer (D) is a reaction formation between the organic polyisocyanate (A) and the active hydrogen group-containing surfactant (B) and the active hydrogen group-containing compound (C) other than (B). The injectable drug solution composition according to (1) above, which is a substance.

(3) The water emulsified solution of the isocyanate group-terminated prepolymer (D) is a mixture of the isocyanate group-terminated prepolymer (D) and water in a mass ratio of 5/95 to 40/60. The injectable drug solution composition according to (1) or (2) above.

(4) The active hydrogen group-containing surfactant (B) is an ionic surfactant, and is characterized by being contained in the isocyanate group-terminated prepolymer (D) at 0.01 to 0.30 mmol / g. The injectable drug solution composition according to any one of (1) to (3) above.

(5) The above-mentioned (1), wherein the active hydrogen group-containing surfactant (B) is a nonionic surfactant and is contained in an isocyanate group-terminated prepolymer (D) in an amount of 1 to 30% by mass. ) To (3). The injectable drug solution composition.

(6) The injectable drug solution composition according to any one of (2) to (5) above, wherein the active hydrogen group-containing compound (C) other than (B) has an average number of functional groups in the range of 2 to 8. thing.

(7) The injectable drug solution composition according to any one of (1) to (6) above is injected into the voids of fine particles, and the water emulsified solution of the isocyanate group-terminated prepolymer (D) in the injectable drug solution composition. A method for producing a fine particle solidified body, which comprises deemulsifying.

(8) The method for producing a fine particle solidified body according to (7) above, wherein an electrolyte is introduced into the water emulsified solution of the isocyanate group-terminated prepolymer (D) in the injectable drug solution composition to deemulsify.

(9) The method for producing a fine particle consolidated body according to (7) above, wherein a voltage is applied to the hydroemulsified solution of the isocyanate group-terminated prepolymer (D) in the injectable drug solution composition to deemulsify the mixture.

(10) The method for producing a fine particle consolidated body according to (7) above, wherein the water emulsified solution of the isocyanate group-terminated prepolymer (D) in the injectable drug solution composition is heated to be emulsified.

The injectable drug solution composition of the present invention can have a low viscosity without using a diluent or a plasticizer that easily causes water pollution, can penetrate even between fine particles having narrow voids such as sand, and is uniform by demilking. A solid solidified body is obtained. Therefore, the workability of on-site construction in a cold season or a cold region is improved, and a foamable resin having excellent permeability and filling property between fine particles having narrow voids such as sand can be obtained. Furthermore, since the elution of the injectable drug solution composition is small, it does not contaminate the water quality.

Hereinafter, the present invention will be described in more detail.

The injectable drug solution composition of the present invention is an injectable drug solution composition containing an emulsified solution of an isocyanate group-terminated prepolymer (hereinafter, also referred to as NCO-terminated prepolymer) (D), wherein the NCO-terminated prepolymer (D) is used. It is characterized by being a reaction product of an organic polyisocyanate (A) and an active hydrogen group-containing surfactant (B).

The NCO-terminated prepolymer (D) used in the present invention can be used without particular limitation as long as it is a reaction product of the organic polyisocyanate (A) and the active hydrogen group-containing surfactant (B). , The reaction product of the organic polyisocyanate (A) and the active hydrogen group-containing surfactant (B) and the active hydrogen group-containing compound (C) other than (B) is preferable.

In the present invention, as the organic polyisocyanate (A), for example, aromatic polyisocyanate, aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic aliphatic polyisocyanate and the like can be used alone or in combination of two or more. ..

<Aromatic polyisocyanate>
Examples of the aromatic polyisocyanate include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, a mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, m-xylylene diisocyanate, p-. Xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate and 4,4'-diphenylmethane Mix of diisocyanates, polyphenylpolymethylpolyisocyanate, 4,4'-diphenyl ether diisocyanate, 2-nitrodiphenyl-4,4'-diisocyanate, 2,2'-diphenylpropane-4,4'-diisocyanate, 3,3'-Dimethyldiphenylmethane-4,4'-diisocyanate,4,4'-diphenylpropanediisocyanate, m-phenylenediocyanate, p-phenylenediisocyanate, naphthylene-1,4-diisocyanate, naphthylene-1,5-diisocyanate, 3,3'-Dimethoxydiphenyl-4,4'-diisocyanate and the like can be mentioned.

<Alphatic polyisocyanate>
Examples of the aliphatic polyisocyanate include hexamethylene diisocyanate, tetramethylene diisocyanate, 2-methyl-pentane-1,5-diisocyanate, 3-methyl-pentane-1,5-diisocyanate, lysine diisocyanate, and trioxyethylene diisocyanate. be able to.

<Alicyclic polyisocyanate>
Examples of the alicyclic polyisocyanate include isophorone diisocyanate, cyclohexane diisocyanate, hydrogenated diphenylmethane diisocyanate, norbornane diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylene diisocyanate, and hydrogenated tetramethylxylylene diisocyanate.

<Aromatic aliphatic polyisocyanate>
Examples of the aromatic aliphatic polyisocyanate include 1,3- or 1,4-xylylene diisocyanate or a mixture thereof, 1,3- or 1,4-bis (1-isocyanato-1-methylethyl) benzene or a mixture thereof. ω, ω'-diisocyanato-1,4-diethylbenzene and the like can be mentioned.

Further, these aromatic polyisocyanates, aliphatic polyisocyanates, alicyclic polyisocyanates, isocyanurate group-containing polyisocyanates obtained from aromatic aliphatic polyisocyanates, uretdione group-containing polyisocyanates, uretdione groups and isocyanurate group-containing polys. Isocyanate, urethane group-containing polyisocyanate, allophanate group-containing polyisocyanate, buretto group-containing polyisocyanate, uretoimine group-containing polyisocyanate and the like can also be used in combination.

In the present invention, an NCO-terminated prepolymer having a high steam pressure is preferable from the viewpoint of the working environment. Therefore, as the organic polyisocyanate (A), particularly 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, etc. Polyphenylpolymethylpolyisocyanate, a mixture of 2,2'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate, is preferable.

Examples of the active hydrogen group-containing surfactant (B) in the present invention include ionic surfactants such as cationic, anionic and betaine-based surfactants, and nonionic nonionic surfactants. Examples of the cationic surfactant include active hydrogen group-containing alkylamine salts, quaternary ammonium salts (imidazolium salt, pyridinium salt, piperidium salt) and the like. Examples of anionic surfactants include active hydrogen group-containing fatty acid salts, higher alcohol sulfate ester salts, alkyl ether sulfate ester salts, alkyl phosphate ester salts, alkane sulfonates, alkylbenzene sulfonates, and polyoxyethylene alkylphenyl ethers. Examples thereof include sulfates and polycarboxylic acid type polymer surfactants. Examples of the betaine-type surfactant include alkyl betaines such as lauryl betaine and stearyl betaine. Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, glycerin fatty acid ester, sucrose fatty acid ester, sorbitan fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, and polyoxyethylene. Examples thereof include polyoxypropylene block copolymers.

When an ionic surfactant is used as the active hydrogen group-containing surfactant (B) in the present invention, one having a conjugated double bond having high emulsion stability is preferable, and an active hydrogen group-containing imidazolium salt is particularly preferable. .. The hydrophilic group content in the ionic surfactant is preferably 0.01 to 0.30 mmol / g, preferably 0.015 to 0.20 mmol / g in the NCO-terminated prepolymer (D). More preferably, 0.02 to 0.10 mmol / g is most preferable. If the hydrophilic group content in the ionic surfactant is less than the lower limit, it may not be emulsified. If the hydrophilic group content in the ionic surfactant exceeds the upper limit, the viscosity of the NCO-terminated prepolymer (D) may increase and the mixing with the dispersion medium may become non-uniform.

The hydrophilic group content of the ionic surfactant can be calculated by the following formula.
Hydrophilic group content of ionic surfactant (mmol / g) =
(Molecular weight of the hydrophilic part in the surfactant / (Molecular weight of the hydrophilic part in the surfactant × Molecular weight of the hydrophilic part in the surfactant)) × (Content of the surfactant in the prepolymer × 0.01).

When a nonionic surfactant is used as the active hydrogen group-containing surfactant (B) in the present invention, a methoxypolyoxyethylene group-containing alcohol having a molecular weight of 600 to 800 is preferable. If the molecular weight of the nonionic surfactant is less than the lower limit, emulsification may be insufficient, and if it exceeds the upper limit, it may become a solid at room temperature and workability may be deteriorated. The content of the nonionic surfactant is preferably 1 to 30% by mass, more preferably 2 to 20% by mass, and 3 to 10% by mass in the NCO-terminated prepolymer (D). Most preferably. If the content of the nonionic surfactant is less than the lower limit, it may not be emulsified, and if it exceeds the upper limit, the compatibility with water increases and the reactivity becomes too fast, and the obtained solidified body strength is adversely affected. May cause.

In the present invention, examples of the active hydrogen group-containing compound (C) other than (B) include low molecular weight alcohols, low molecular weight amines, low molecular weight amino alcohols, low molecular weight glycol ethers, polyester polyols, and polyether polyols. Classes, polycarbonate polyols and the like. These can be used alone or in combination of two or more.

Examples of low molecular weight alcohols include methyl alcohol, ethyl alcohol, n-propyl alcohol, n-butyl alcohol, n-amyl alcohol, n-hexyl alcohol, n-heptyl alcohol, n-octyl alcohol, and n-nonyl alcohol. n-decyl alcohol, n-lauryl alcohol, n-tridecyl alcohol, n-tetradecyl alcohol, n-pentadecyl alcohol, n-heptadecyl alcohol, n-octadecyl alcohol (stearyl alcohol), isopropyl alcohol, isobutyl alcohol, 2 -Ethylhexanol, methyl-1-nonanol, dimethyl-1-octanol, tetramethyl-1-hexanol, 3-ethyl-4,5,6-trimethyloctanol, 4,5,6,7-tetramethylnonanol, tridecanol , Tetradecanol, 2-hexyldodecanol, 2-hexadecyloctanol, cyclohexanol, cyclohexanemethanol, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1, , 5-Pentadiol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, 2-n- Butyl-2-ethyl-1,5-pentanediol, 2-n-butyl-2-ethyl-1,3-propanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1, Examples thereof include 3-hexanediol, glycerin, trimethylolpropane, pentaerythritol and the like alone or in admixture of two or more.

Examples of low molecular weight amines include ethylamine, butylamine, diethylamine, dibutylamine, aniline, N-methylaniline, diphenylamine, ethylenediamine, propylenediamine, diethylenetriamine, toluenediamine, metaphenylenediamine, diphenylmethanediamine, xylylenediamine, etc. alone or Examples include a mixture of two or more.

Examples of the low molecular weight amino alcohols include monoethanolamine, diethanolamine, N- (β-aminoethyl) ethanolamine and the like alone or a mixture of two or more kinds.

Examples of low molecular weight glycol ethers include ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monobutyl ether, ethylene glycol monohexyl ether, diethylene glycol monohexyl ether, and ethylene glycol mono-2-ethylhexyl ether. , Propylene Glycol Monomethyl Ether, Glycol Ethers such as Dipropylene Glycol Monomethyl Ether, etc. alone or a mixture of two or more.

Examples of polyester polyols include those having two or more active hydrogen groups in one molecule among the above-mentioned low molecular weight alcohols, low molecular weight amines, and low molecular weight alcohols, and succinic acid, adipic acid, sebacic acid, and azeline. With one or more of polycarboxylic acids such as acid, terephthalic acid, isophthalic acid, orthophthalic acid, hexahydroorthophthalic acid, naphthalenedicarboxylic acid, trimellitic acid, hexahydrotrimellitic acid, acid ester, acid anhydride and the like. Examples thereof include a polyester polyol or a polyesteramide polyol obtained by a dehydration condensation reaction. Further, a lactone-based polyester polyol obtained by ring-opening polymerization of a cyclic ester (lactone) monomer such as ε-caprolactone and γ-butyrolactone can be mentioned.

Examples of the polycarbonate polyol include those having two or more active hydrogen groups in one molecule among the above-mentioned alcohols and those obtained by a dealcohol reaction with diethylene carbonate, dimethyl carbonate, diphenyl carbonate and the like.

Examples of the polyether polyol include the above-mentioned alcohols, amines and amino alcohols as initiators, and alkylenes such as ethylene oxide (hereinafter abbreviated as EO), propylene oxide (hereinafter abbreviated as PO), butylene oxide and amylene oxide. It can be obtained by addition polymerization of a cyclic ether monomer such as an oxide, an aryl glycidyl ether of methyl glycidyl ethers, or a isocyanate alone or a mixture by a known method.

The average number of functional groups of the active hydrogen group-containing compound (C) in the present invention is preferably 2 to 8. If the average number of functional groups is less than 2, the strength of the obtained solidified body may be insufficient, while if the average number of functional groups exceeds 8, the viscosity of the obtained NCO-terminated prepolymer (D) becomes too high. There is a fear. The molecular weight of the active hydrogen group-containing compound (C) is preferably 18 to 5000. The active hydrogen group-containing compound (C) is preferably used in an amount of 1 to 50 parts by mass, more preferably 2 to 40 parts by mass, based on 100 parts by mass of the organic polyisocyanate (A).

In the injection liquid composition of the present invention, if necessary, surfactants and catalysts other than the above, other pigments, dyes, fillers, antigelling agents, coupling agents, foaming agents, dispersants, antioxidants Although various additives such as an ultraviolet absorber and a heat resistance imparting agent can be added, it is preferable to limit the addition to those that do not cause elution into the aqueous phase.

The mass mixing ratio of the NCO-terminated prepolymer (D) and water in the present invention is preferably 5/95 to 40/60, more preferably 10/90 to 35/65, and 20/80 to 30. It is most preferably / 70. When the content of the NCO-terminal prepolymer (D) exceeds the upper limit, the phase inversion viscosity that changes from the oil-in-water emulsion type emulsion to the water-in-oil droplet-type emulsion approaches, and the viscosity of the water emulsion of the NCO-terminal prepolymer (D) becomes high. It may become high and the permeability may deteriorate.

In the method for producing a fine particle solidified body of the present invention, the above-mentioned injectable drug solution composition of the present invention is injected between fine particles having narrow voids, and the isocyanate group-terminated prepolymer (D) in the injectable drug solution composition is emulsified. Its characteristic is to emulsify the liquid.

In the present invention, as a method for emulsifying the water-emulsified solution of the isocyanate group-terminated prepolymer (D), for example, a method of introducing an electrolyte into the water-emulsified solution of the isocyanate group-terminated prepolymer (D), an isocyanate group-terminated prepolymer. Examples thereof include a method of applying a voltage to the aqueous emulsion of (D) and a method of heating the aqueous emulsion of the isocyanate group-terminated prepolymer (D).

First, the electrolytic solution used for deemulsifying the water emulsified solution of the NCO-terminated prepolymer (D) will be described.

When an ionic surfactant is used as the active hydrogen group-containing surfactant (C), the charged dispersed particles in the water emulsion of the NCO-terminated prepolymer (D) have an increased electrolyte concentration in the dispersion medium. Due to the influence of the osmotic pressure due to the difference in ion concentration between the dispersed particles and the electrolytic solution, the water held by the dispersed particles is dehydrated and emulsified, and the phase is separated into an aqueous phase and an oil phase.

Examples of the electrolyte for deemulsification include acid salts such as sodium hydrogensulfate and sodium hydrogencarbonate, basic salts such as magnesium chloride, positive salts such as sodium chloride, sodium sulfate and magnesium chloride, sulfuric acid and hydrochloric acid. Etc., a commercially available buffer solution can be used as it is. Of these, sodium chloride, magnesium chloride (hexahydrate), sodium sulfate, and sodium hydrogencarbonate, which are highly safe, are preferable from the viewpoint of environmental pollution.

In the present invention, the concentration of the electrolyte for deemulsifying the water emulsion is preferably 1.6% by mass or more with respect to the NCO-terminated prepolymer (D) and less than the solubility of each electrolyte. If the electrolyte concentration is less than the lower limit, emulsification will be insufficient and the COD value will exceed the upper limit (8 mg / L) (hereinafter referred to as the environmental standard) indicated by the environmental standard (lakes) regarding the conservation of living environment notified by the Ministry of the Environment. There is a fear. If the electrolyte concentration exceeds the upper limit, the electrolyte will be excessively added, which is uneconomical.

Next, a deemulsification method for heating the hydroemulsified solution of the NCO-terminated prepolymer (D) will be described.

When a nonionic surfactant is used as the active hydrogen group-containing surfactant (C), the dispersed particles in the water emulsion of the NCO-terminated prepolymer (D) have an ether group in the surfactant of water and hydrogen. Emulsify by binding. When the temperature of the emulsion is raised, the molecular motion of water becomes violent, and when the temperature exceeds the temperature (cloud point) at which the hydrogen bond between the ether group and water is broken, the emulsified liquid is emulsified.

In the present invention, it is preferable to heat the water emulsified solution of the NCO-terminated prepolymer (D) containing the nonionic surfactant to 40 to 90 ° C.

Next, deemulsification in which a voltage is applied to the water emulsified solution of the NCO-terminated prepolymer (D) will be described.

When an ionic surfactant is used as the active hydrogen group-containing surfactant (C), the hydroemulsified solution of the NCO-terminated prepolymer (D) can be emulsified by applying a voltage. It is preferable to apply an AC voltage of 1 to 50 V / cm to the water emulsified solution of the NCO-terminated prepolymer (D), and even more preferably 30 to 50 V / cm. If the voltage is less than the lower limit, the emulsification may be insufficient and the water phase and the oil phase may not be separated from each other, and if the voltage exceeds the upper limit, the human body may be adversely affected.

In the present invention, the hydroemulsified solution of the NCO-terminated prepolymer (D) is emulsified by each of the above-mentioned methods and phase-separated into an aqueous phase and an oil phase so that the COD value is less than the upper limit of the environmental standard and the strength is further increased. A solidified body is obtained.

As described above, according to the present invention, since the viscosity of the water emulsion of the NCO-terminated prepolymer (D) is low, the injectable drug solution composition can be permeated even in a narrow part of the flow path. Furthermore, by taking advantage of its low viscosity, strength, and environmental compatibility, it can be used as a concrete repair material, ground improvement material, binder for molded bodies of lignocellulosic materials, adhesives, coagulants for water treatment and suspensions in pulp and paper. Can also be used.

Hereinafter, examples of the present invention will be described, but the present invention is not limited to these examples. Unless otherwise specified, "parts" and "%" in Examples and Comparative Examples indicate "parts by mass" and "% by mass", respectively.

In the present invention, the zeta potential and the measured particle size were used as indicators of emulsion stability.

Whether the dispersed particles in the emulsion are dispersed or aggregated is determined by the sum of the van der Waals attractive force and the electrostatic repulsive energy acting between the dispersed particles. Van der Waals When the attractive force is high, the dispersed particles are aggregated, and when the electrostatic repulsive energy is high, they are emulsified. The charged dispersed particles form a diffusion electric double layer in which counterions have a fixed layer and a diffusion layer around the charged particles. The potential of the slip surface where the liquid flow between the fixed layer and the diffusion layer occurs is the zeta potential. The zeta potential is a measure of the amount of charge of dispersed particles, and when the zeta potential is high, the electrostatic repulsive energy is also high and the emulsification stability is high. On the other hand, when the zeta potential is -25 to 25 mV, the van der Waals attractive force exceeds the electrostatic repulsive energy, so that the emulsification stability is lowered and aggregated.

When a nonionic surfactant is used as the active hydrogen group-containing surfactant (C), the zeta potential is -25 because the dispersed particles in the water emulsion of the NCO-terminated prepolymer (D) are not charged. Emulsification stability may be high even within the range of ~ 25 mV. Therefore, in the case of an NCO-terminated prepolymer using a nonionic surfactant as the active hydrogen group-containing surfactant (C), the particle size of the dispersed particles is used as an index of emulsion stability. In the present invention, when the particle size of the dispersed particles is 10 μm (10000 nm) or more, the dispersed particles tend to settle, and it is evaluated that the emulsion stability is poor.

(Manufacturing Example 1)
After replacing the reactor equipped with a stirrer, a cooling tube, a nitrogen introduction tube, and a thermometer with nitrogen, 1- (2-hydroxyethyl) -imidazole (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) 100.0 g and 1 were added to this reactor. -Chlorooctane (manufactured by Tokyo Chemical Industry Co., Ltd.) 198.9 g was charged and reacted at 100 ° C. for 46 hours with stirring. Then, it was confirmed by ¹ H-NMR that there was no unreacted 1- (2-hydroxyethyl) -imidazole, and an imidazolium salt was obtained.

After replacing the reactor equipped with a stirrer, cooling pipe, nitrogen introduction pipe, and thermometer with nitrogen, 770 g of Polymeric MDI (trade name: MR-200, manufactured by Toso Co., Ltd.) was charged into this reactor, and then polyoxypropylene glycol. (Number of functional groups 2, molecular weight 2000, trade name: PP-2000, manufactured by Sanyo Kasei Kogyo Co., Ltd.) 200 g was charged, and then a mixed solution consisting of 15.9 g of the imidazolium salt and 14.1 g of methanol was charged while stirring at room temperature. The reaction was carried out for 3 hours with stirring at 80 ° C., and the isocyanate group content was 20.3%, the viscosity at 25 ° C. was 3,000 mPa · s, and the hydrophilic group content of the active hydrogen group-containing surfactant was 0.07 mmol / g. NCO-terminated prepolymer (D-1) containing an ionic (cationic) surfactant was obtained.

(Manufacturing Example 2)
After replacing the reactor equipped with a stirrer, nitrogen introduction tube, and thermometer with nitrogen, 840 g of polymeric MDI (trade name: MR-200, manufactured by Toso Co., Ltd.) was charged into this reactor, and then polyoxyethylene polyoxypropylene glycol (polyoxyethylene polyoxypropylene glycol). The number of functional groups is 2, the molecular weight is 3000, the ethylene oxide content is 70%, the trade name is PR-3007, manufactured by Adeca, and 100 g is charged, and then the sodium sulfonate-containing polyester polyol (number of functional groups 2, hydroxyl value 110 KOHmg / g, acid value 0. 99KOHmg / g, trade name: N-4072, manufactured by Toso Co., Ltd.) was charged while stirring at room temperature, and reacted at 80 ° C. for 3 hours to have an isocyanate group content of 23.9% and 25 ° C. An NCO-terminated prepolymer (D-2) containing an ionic (anionic) surfactant having a viscosity of 2,700 mPa · s and a hydrophilic group content of 0.02 mmol / g of the active hydrogen group-containing surfactant was obtained.

(Manufacturing Example 3)
After replacing the reactants equipped with a stirrer, cooling pipe, nitrogen introduction pipe, and thermometer with nitrogen, 750 g of Polymeric MDI (trade name: MR-200, manufactured by Toso Co., Ltd.) was charged into this reactor, and then polyoxypropylene glycol (polyoxypropylene glycol). Charged with 200 g of functional group number 2, molecular weight 2000, trade name: PP-2000, manufactured by Sanyo Kasei Kogyo Co., Ltd., and then methoxypolyoxyethylene glycol (functional group number 1, molecular weight 700, trade name: MPG-081, manufactured by Nippon Embroidery Co., Ltd.). 50 g was charged and reacted for 3 hours while stirring at 80 ° C., the isocyanate group content was 21.3%, the viscosity at 25 ° C. was 2,530 mPa · s, and the content of the active hydrogen group-containing surfactant was 5 mass. % Nonionic (nonionic) surfactant-containing NCO-terminated prepolymer (D-3) was obtained.

Various evaluations were performed by the following evaluation methods.

<Preparation of water emulsified liquid>
-Method for preparing a water emulsion (a)
20 g of various NCO-terminated prepolymers (D) (hereinafter also referred to as (D)) adjusted to 25 ° C. and 80 g of water are weighed in a 500 ml polycup, mixed with a three-one motor at 500 rpm for 10 seconds, and emulsified. Obtained liquid.

-Measuring method of viscosity of water-emulsified liquid The water-emulsified liquid of (D) obtained in the method for preparing a water-emulsified liquid (a) was used as a No. 2 rotor using a B-type viscometer (manufactured by Tokyo Keiki Co., Ltd., model "DVL-BII type"). The viscosity at 25 ° C. was measured.

-Zeta potential and particle size measurement method 0.5 g of the hydroemulsified solution of (D) obtained in the hydroemulsified solution preparation method (a) was added dropwise to 9.0 g (25 ° C.) of purified water to prepare a mixed solution (mixing). Liquid (e)), zeta potential measurement and particle size measurement were performed with ELSZ-2000 manufactured by Otsuka Electronics Co., Ltd.

-Emulsification property evaluation When the zeta potential of the dispersed particles of the mixed solution (e) was outside the range of -25 to 25 mV or the particle size was 10 μm (10,000 nm) or less, the emulsification stability was good.

<Method for measuring permeability and consolidation strength>
The solidified body strength was measured from the permeability and uniaxial compressive strength by the sand column method (Geoflonte Study Group, Urethane Injection Offering Technology, Paint Magazine, Standard Test Method).

・ Permeability evaluation After putting 180 g of commercially available No. 4 silica sand inside an acrylic pipe with a diameter of 40 mm, excess water was put in and vibrated to compact the silica sand and excess water was discharged to make the sand height about 10 cm. .. Next, the porosity when No. 4 silica sand was used in the pipe was calculated by the following formula, and the filling amount of the water emulsified liquid of (D) was calculated by the porosity with the specific gravity of the water emulsified liquid being 1. The calculated amount of the water emulsified solution (D) was injected onto the compacted sand, and the permeation distance in the sand was measured with a caliper to evaluate the permeability.

<Porosity and filling amount calculation formula>
1) Volume when No. 4 silica sand is compacted in the above pipe 2 x 2 x 3.14 x 10 = 125.6 (cm ³ )
2) Porosity of the compacted sand considering the porosity of No. 4 silica sand of 40% 125.6 × 0.4 = 50.3 (cm ³ )
3) Filling amount 50.3 × 1 = 50.3 (g) obtained by setting the specific gravity of the water emulsified solution of (D) to 1.
A permeation distance of 10 cm or more was considered good.

-Consolidation strength measuring method A uniaxial compressive strength test was conducted in accordance with JIS K 1216 using a consolidated body having a diameter of 40 mm and a height of 10 cm prepared in the above permeability evaluation.

<Emulsion method (d)>
(D-1: Examples 1 and 2, Reference Example 1)
To 100 g of the water emulsion obtained by the method for preparing a water emulsion (a), an electrolyte prepared so that the electrolyte concentration with respect to the various isocyanate group-terminated prepolymers (D) shown in Table 1 was a predetermined concentration was added. The evaluation results are shown in Table 1.

(D-2: Example 3, Reference Examples 2 to 3)
100 g of the water emulsion obtained by the water emulsion preparation method (a) was stored in a constant temperature bath (manufactured by ADVANTEC, model "DRS620DA") adjusted to a predetermined temperature. The evaluation results are shown in Table 2.

(D-3: Examples 4 to 5, Reference Example 4)
100 g of the water emulsified liquid obtained in the water emulsified liquid preparation method (a) was placed in a container in which a pair of strip-shaped stainless steel plates were arranged facing each other, and an AC voltage of 10 V / cm or 40 V / cm was applied. The evaluation results are shown in Table 3.

-Evaluation of emulsifying property (D) was evaluated visually to see if (D) was phase-separated into an aqueous phase and an oil phase after emulsification by the methods (d-1) to (d-3) above.

Phase separation between water phase and oil phase: 〇 No phase separation between water phase and oil phase: ×.

<Consolidation appearance evaluation method>
The appearance of the consolidated body was evaluated 12 hours after the tests of the various demineralization methods (d).

Good: Uniform foam with strength Poor: Non-uniform soft foam or uncured.

<COD measurement method in aqueous phase>
After the test of the emulsification method (d), water on the aqueous phase side was sampled, and the COD value was measured using the COD pack test WAK-COD manufactured by Kyoritsu Institute of Physical and Chemical Research. From the environmental standard, it was judged to be good if the COD value was 8 mg / L or less.

From the above results, in the examples, the hydroemulsified solution was emulsified and phase-separated into an aqueous phase and an oil phase, so that a strong solidified body could be obtained.

After deemulsification, the COD value on the aqueous phase side also satisfies 8 mg / L or less in all the examples, so it can be said that there is no problem with respect to water pollution.

Claims (9)

An injectable drug solution composition containing a water emulsion of the isocyanate group-terminated prepolymer (D) is injected into the voids of fine particles, and the water emulsified solution of the isocyanate group-terminated prepolymer (D) in the injectable drug solution composition is deemulsified. A method for producing a fine particle solidified body , wherein the isocyanate group-terminated prepolymer (D) is a reaction product of an organic polyisocyanate (A) and an active hydrogen group-containing surfactant (B). A method for producing a fine particle solidified body , which is characterized by being. The isocyanate group-terminated prepolymer (D) is a reaction product of the organic polyisocyanate (A) and the active hydrogen group-containing surfactant (B) and the active hydrogen group-containing compound (C) other than (B). The method for producing a fine particle solidified body according to claim 1, wherein the method is characterized by the above. The claim is characterized in that the water emulsified solution of the isocyanate group-terminated prepolymer (D) is a mixture of the isocyanate group-terminated prepolymer (D) and water in a mass ratio of 5/95 to 40/60. The method for producing a fine particle solidified body according to 1 or 2. Claim 1 is characterized in that the active hydrogen group-containing surfactant (B) is an ionic surfactant and is contained in the isocyanate group-terminated prepolymer (D) at 0.01 to 0.30 mmol / g. The method for producing a fine particle solidified body according to any one of 3 to 3. The active hydrogen group-containing surfactant (B) is a nonionic surfactant, and is contained in an isocyanate group-terminated prepolymer (D) in an amount of 1 to 30% by mass according to claims 1 to 3. The method for producing a fine particle solidified body according to any one. The method for producing a fine particle consolidated body according to any one of claims 2 to 5, wherein the average number of functional groups of the active hydrogen group-containing compound (C) other than (B) is in the range of 2 to 8. The method for producing a fine particle solidified body according to any one of claims 1 to 6, wherein an electrolyte is introduced into the emulsified solution of the isocyanate group-terminated prepolymer (D) in the injectable drug solution composition to deemulsify. .. The method for producing a fine particle consolidated body according to any one of claims 1 to 6, wherein a voltage is applied to the hydroemulsified solution of the isocyanate group-terminated prepolymer (D) in the injectable drug solution composition to deemulsify the mixture. .. The method for producing a fine particle consolidated body according to any one of claims 1 to 6, wherein the water emulsified solution of the isocyanate group-terminated prepolymer (D) in the injectable drug solution composition is heated to be emulsified.