JPH0680955A - Production of particulate oil absorbent - Google Patents

Abstract

PURPOSE:To obtain the title absorbent which absorbs a large amt. of various oils even in an oil-water mixture and has a high oil-reserving capacity and a high oil absorption rate by reacting an org. carboxylic acid with a metal compd. capable of forming a salt therewith in an aq. medium in the presence of particles of a specific oil-absorbing crosslinked polymer to thereby coat the surfaces of the particles with the resulting salt. CONSTITUTION:An oil-absorbing crosslinked polymer is obtd. by copolymerizing 96-99.999wt.% monomer component having a polymerizable unsatd. group in the molecule and mainly comprising a monomer having a solubility parameter of 9 or lower with 0.001-4wt.% crosslinking monomer having at least two polymerizable unsatd. groups by e.g. bulk polymn. The title absorbent is obtd. by mixing an org. carboxylic acid (e. g. butyric acid) with a metal compd. (e.g. an Li compd. able of forming a salt therewith in an aq. medium in the presence of particles of the polymer having a mean particle size of 0.5-500mum to form the salt on the surfaces of the particles. The absorbent comprises 30-99.9wt.% the polymer and 70-0.2wt.% the salt.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing an oil absorbent. More specifically, a granular oil-absorbing agent that absorbs a large amount of oil and swells against a wide variety of oils even from an oil-water mixed system, has excellent oil-holding performance of the absorbed oil, and has a significantly improved oil-absorption rate Well about manufacturing methods.

[0002]

2. Description of the Related Art In recent years, the recovery of oil spilled into the sea and oil in waste water has become a major environmental issue. Further, there is a strong demand for a simple method for treating leaked oil such as small-scale waste oil discarded in homes and factories and machine oil in factories.

[0003] As one of the effective means for recovering these oil spills and oil components in waste water or treating waste oil and oil leaks, a method of adsorbing oil with an oil absorbent and then incineration or other post-treatment has been conventionally used. Has been. As such an oil absorbing material,
For example, a synthetic fiber oil absorbing material made of a hydrophobic fiber such as polypropylene fiber, polystyrene fiber, polyethylene fiber or a nonwoven fabric thereof has been used. However, the conventional synthetic fiber-based oil absorbent material is inferior in oil retention performance after oil absorption because the oil absorbing action is due to adsorption and holding of the oil in the voids existing in the oil absorbent material due to the capillary phenomenon, so that it is less than the low viscosity oil. Has substantially no oil retaining ability, and since the oil that was easily absorbed is re-released even with viscous oil with a slight external pressure, liquid sagging easily occurs and post-treatment becomes extremely complicated. Was. Also, when applied to the recovery of oil content of oil-water mixed system or thin film oil floating on the water surface, the recovery rate of oil is poor and a large amount of water is absorbed, so the oil absorbing material sinks in water and is difficult to recover. However, there is a problem in that combustion after recovery is inconvenient.

As means for solving these problems, some synthetic resin type oil absorbents of the type in which oil is absorbed and swelled in a certain polymer have been reported. For example,
A copolymer of t-butylstyrene / divinylbenzene (JP-A-45-27081), a cross-linked polymer of t-butyl methacrylate and / or neopentyl methacrylate (JP-A-50-15882), and menthyl methacrylate of Cross-linked polymer (JP-A-50-59486), polynorbornene rubber (for example, Nosolex AP manufactured by CdF), and cross-linked polymer of alkyl (meth) acrylate having 10 to 16 carbon atoms (JP-A-3-221).
582) and the like. These oil-absorbing agents have an oil-absorption function because they absorb oil into the molecule having a hydrophobic structure and swell, so that only oil is added to the oil content of oil-water mixed systems and thin-film oil floating on the water surface. Absorbs selectively,
Moreover, it has advantages such as excellent oil retaining ability for oil once absorbed.

However, these synthetic resin-based oil absorbents have the drawback that the time required for oil absorption is extremely long as compared with synthetic fiber oil absorbents, and in particular, they have a low oil absorption rate for highly viscous oils. There was a problem.

Therefore, in order to improve the oil absorption speed, measures have been taken to increase the surface area of these oil absorbents by processing these oil absorbents into fine particles. However, as the oil-absorbing agent becomes finer, the particles tend to agglomerate with each other, so that the actually expected sufficient oil-absorption rate has not been obtained. Therefore, these oil absorbing agents have a drawback that they are difficult to be applied to the field in which it is required to absorb the oil in a short time, such as when an oil spill accident occurs.

[0007]

SUMMARY OF THE INVENTION The present invention solves the above problems of conventional oil absorbents. That is, the object of the present invention is to absorb a large amount of oil to a wide variety of oils even from an oil-water mixed system and swell, and the oil absorption performance of the absorbed oil is excellent, and the oil absorption speed is remarkably improved. An object of the present invention is to provide a method for producing a granular oil-absorbing agent, which can easily produce the agent with good reproducibility.

[0008]

The inventors of the present invention have made the crosslinked polymer and the organic acid metal salt by reacting an organic carboxylic acid and a metal compound in an aqueous medium in the presence of particles of a specific oil-absorbing crosslinked polymer. It was found that a granular oil-absorbing agent satisfying the above-mentioned object can be produced easily and with good reproducibility by compounding the above, and the present invention has been completed.

That is, according to the present invention, the monomers (A) 96 to 9 having one polymerizable unsaturated group in the molecule whose main component is a monomer having a solubility parameter (SP value) of 9 or less.
9.999% by weight and 0.001 to 4 crosslinkable monomer (B) having at least two polymerizable unsaturated groups in the molecule
% By weight (however, the sum of monomers (A) and (B) is 10
(0% by weight) is added, and an organic carboxylic acid and a metal capable of forming a salt by a reaction with an organic carboxylic acid in the presence of the oil-absorbing crosslinked polymer (I) in the form of particles. The compounds are mixed in an aqueous medium and the organic acid metal salt (I
The present invention relates to a method for producing a granular oil-absorbing agent containing an oil-absorbing crosslinked polymer (I) and an organic acid metal salt (II), which is characterized by producing I).

[0010]

The solubility parameter (SP value) is generally used as a measure of the polarity of a compound, and in the present invention, the value derived by substituting the Hoy cohesive energy constant into the Small calculation formula is applied. And the unit (cal /
expressed in cm ^{3) 1/2.}

The monomer constituting the main component of the monomer (A) used in the present invention is a monomer having a solubility parameter (SP value) of 9 or less and having one polymerizable unsaturated group in the molecule. If a monomer having a solubility parameter (SP value) of more than 9 is used as the main component of the monomer (A), only a crosslinked polymer having insufficient oil absorption performance can be obtained, which is not preferable.

Examples of the monomer having a solubility parameter (SP value) of 9 or less and having one polymerizable unsaturated group in the molecule include, for example, methyl (meth) acrylate, ethyl (meth) acrylate and butyl (meth). Acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate,
Dodecyl (meth) acrylate, stearyl (meth) acrylate, phenyl (meth) acrylate, octylphenyl (meth) acrylate, nonylphenyl (meth) acrylate, dinonylphenyl (meth) acrylate, cyclohexyl (meth) acrylate, menthyl (meth) Unsaturated carboxylic acid esters such as acrylate, isobornyl (meth) acrylate, dibutyl maleate, didodecyl maleate, dodecyl crotonate, didodecyl itaconate; (di) butyl (meth) acrylamide, (di) dodecyl (meth) acrylamide ,
(Meth) acrylamide having a hydrocarbon group such as (di) stearyl (meth) acrylamide, (di) butylphenyl (meth) acrylamide, (di) octylphenyl (meth) acrylamide; 1-hexene, 1-octene, isooctene, Α-Olefins such as 1-nonene, 1-decene, 1-dodecene; alicyclic vinyl compounds such as vinylcyclohexane; allyl ethers having a hydrocarbon group such as dodecyl allyl ether; vinyl caproate, vinyl laurate, palmitic acid Vinyl ester having a hydrocarbon group such as vinyl and vinyl stearate;
Vinyl ether having a hydrocarbon group such as butyl vinyl ether and dodecyl vinyl ether; aromatic vinyl compounds such as styrene, t-butyl styrene, octyl styrene and the like can be mentioned, and one or more of these monomers can be used. You can Among these, as a monomer that gives better oil absorption performance and oil retention performance,
It has at least one aliphatic hydrocarbon group having 3 to 30 carbon atoms, and is alkyl (meth) acrylate, alkylaryl (meth) acrylate, alkyl (meth) acrylamide, alkylaryl (meth) acrylamide,
The monomer (A) containing as a main component at least one unsaturated compound (a) selected from the group consisting of fatty acid vinyl ester, alkylstyrene and α-olefin is particularly preferable.

Such solubility parameter (SP value)
Is 9 or less, the amount used in the monomer (A) is
The proportion is 50% by weight or more, more preferably 70% by weight or more, based on the total amount of the monomer (A). When the amount of the monomer having the solubility parameter (SP value) of 9 or less in the monomer (A) is less than 50% by weight, only a crosslinked polymer having poor oil absorption performance and oil retention performance can be obtained.

Therefore, in the present invention, 5 monomers having a solubility parameter (SP value) of 9 or less are included in the monomer (A).
It is necessary that the content of the solubility parameter (SP) is 50% by weight or less in the monomer (A), although the content of SP is 0% by weight or more.
A monomer having one polymerizable unsaturated group may be contained in a molecule whose value) exceeds 9. Examples of such a monomer include (meth) acrylic acid, acrylonitrile, maleic anhydride, fumaric acid, hydroxyethyl (meth) acrylate, polyethylene glycol (meth) acrylate, and methoxypolyethylene glycol (meth) acrylate. You can

Examples of the crosslinkable monomer (B) used for polymerizing the oil-absorbent crosslinked polymer (I) in the present invention include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate and polyethylene. Glycol di (meth) acrylate, polyethylene glycol-polypropylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, 1,
3-butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-
Hexanediol di (meth) acrylate, N, N'-
Methylenebisacrylamide, N, N'-propylenebisacrylamide, glycerin tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, polyhydric alcohol (for example, glycerin, trimethylolpropane or tetra). Examples thereof include polyfunctional (meth) acrylate obtained by esterification of alkylene oxide adduct of (methylolmethane) and (meth) acrylic acid, divinylbenzene, etc., and one or two kinds of these crosslinkable monomers. The above can be used.

The ratio of the monomer (A) and the crosslinkable monomer (B) in the monomer component used for producing the oil-absorbent crosslinked polymer (I) is as follows. The amount of the monomer (A) is 96 to 99.9 based on the total amount of the crosslinkable monomer (B).
99% by weight, the crosslinkable monomer (B) is 0.001-
It is in the range of 4% by weight.

When the amount of the monomer (A) is less than 96% by weight or the amount of the crosslinkable monomer (B) exceeds 4% by weight, the crosslink density of the obtained crosslinked polymer becomes too high and a large amount of oil is obtained. It is not preferable because it cannot be absorbed. Further, the monomer (A) is 9
If it exceeds 9.999% by weight or the crosslinkable monomer (B) is less than 0.9.
If it is less than 001% by weight, the solubility of the resulting crosslinked polymer in oil is increased, and the crosslinked polymer is fluidized after oil absorption and the performance as an oil absorbing agent cannot be obtained, which is not preferable.

Oil-absorbing crosslinked polymer (I) in the present invention
Is, for example, the above-mentioned monomer component in an aqueous medium, polyvinyl alcohol, hydroxyethyl cellulose, a protective colloid agent such as gelatin or sodium alkylsulfonate,
It can be produced by dispersing in the presence of a surfactant such as sodium alkylbenzene sulfonate, polyoxyethylene alkyl ether, and fatty acid soap, and suspension-polymerizing with an oil-soluble radical polymerization initiator. If necessary, the monomer component may be dissolved in a water-insoluble organic solvent and then suspension-polymerized. An aqueous dispersion of the cross-linked polymer (I) particles can be obtained by such suspension polymerization, and can be used as it is in the production step of the organic acid metal salt (II) described later. Examples of the oil-soluble radical polymerization initiator include organic peroxides such as benzoyl peroxide, lauroyl peroxide and cumene hydroperoxide; 2,2′-azobisisobutyronitrile and 2,2′-azobisdimethylvalero. An azo compound such as nitrile can be used. The polymerization temperature can be appropriately selected within the range of 0 to 150 ° C. depending on the type of monomer component and the type of polymerization initiator.

In the present invention, as a method for producing the oil-absorptive crosslinked polymer (I), after the oil-absorptive crosslinked polymer (I) is polymerized by bulk polymerization, an operation such as pulverization is added to adjust the particle size to obtain granular particles. You can give a way to make things.
Bulk polymerization may be carried out, for example, by pouring a monomer component into a mold in the presence of the above-mentioned polymerization initiator and conducting the polymerization under the condition of 50 to 150 ° C.

In the present invention, the oil-absorbing crosslinked polymer (I)
Is preferably a granular material having an average particle size in the range of 0.5 to 500 μm by introducing a pre-suspension step using a homomixer during suspension polymerization or adjusting the stirring power during polymerization. When the average particle size of the particles of the oil-absorbent crosslinked polymer (I) is less than 0.5 μm, the surface area is reduced due to the Mamako phenomenon based on the aggregation of the particles, and an oil absorbent having an improved oil absorption rate can be obtained. It will be difficult. Further, if the average particle diameter of the granular particles of the oil-absorbent crosslinked polymer (I) exceeds 500 μm, the oil absorption rate also decreases as the surface area of the crosslinked polymer decreases, which is not preferable.

The organic carboxylic acid used in the present invention is not particularly limited as long as it produces a substantially water-insoluble organic acid metal salt (II) by a reaction with a metal compound described below, and examples thereof include butyric acid and capron. Linear saturated fatty acids such as acids, caprylic acid, pelargonic acid, capric acid, undecanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, and arachidic acid; linear unsaturated fatty acids such as oleic acid, linoleic acid, and linolenic acid Branched fatty acids such as isostearic acid; fatty acids containing hydroxyl groups such as ricinoleic acid and 12-hydroxystearic acid; benzoic acid;
Naphthenic acid; Organic carboxylic acids such as abietic acid, rostropic acid such as dextropimaric acid, and the like,
These 1 type (s) or 2 or more types can be used. Among these organic carboxylic acids, monovalent fatty acids having 3 to 30 carbon atoms are particularly preferable.

The metal compound used in the present invention is not particularly limited as long as it produces a substantially water-insoluble organic acid metal salt (II) by the reaction with the organic carboxylic acid, and examples thereof include lithium, copper and Beryllium, magnesium, calcium, strontium, barium, zinc, cadmium, aluminum, cerium, titanium, zirconium,
Examples thereof include oxides, hydroxides, carbonates and basic carbonates of lead, chromium, manganese, cobalt, nickel and the like, and one or more of these can be used.

According to the production method of the present invention, the above-mentioned organic carboxylic acid and the metal compound are mixed in an aqueous medium in the presence of the particulate matter of the oil-absorbing crosslinked polymer (I) to carry out a reaction to carry out the oil-absorbing crosslinked polymer It is possible to obtain a granular oil absorbing agent in which the organic acid metal salt (II) is uniformly compounded in the combined product (I). As a specific operation, for example, the organic carboxylic acid is preferably heated and dissolved, and then mixed with the oil-absorbing crosslinked polymer (I) in an aqueous medium in the presence of a surfactant if necessary, and the metal compound is further added. A granular oil absorbing agent comprising the oil-absorbing cross-linked polymer (I) and the organic acid metal salt (II) can be obtained by adding and mixing to carry out a reaction and performing a treatment such as drying or pulverization.
The reaction may be carried out by reversing the order of addition of the organic carboxylic acid and the metal compound or simultaneously adding and mixing them. The reaction temperature is appropriately determined according to the type of organic carboxylic acid or metal compound used, but it is preferable to react in the range of 60 to 120 ° C.

Further, as an effective means in the production method of the present invention, an aqueous dispersion of the oil-absorbing crosslinked polymer (I) obtained by suspension polymerization is used as it is and mixed with an organic carboxylic acid and a metal compound to carry out a reaction. The method of doing can also be adopted.

The organic acid metal salt (II) in the present invention is a substantially water-insoluble compound formed by the reaction between the above-mentioned organic carboxylic acid and the metal compound, and is a combination of the above-mentioned organic carboxylic acid and the metal compound. It consists of various compounds. Examples thereof include organic acid polyvalent metal salts such as magnesium stearate, calcium stearate, calcium laurate, and zinc caprylate.

The mixing ratio of the oil-absorptive cross-linked polymer (I) and the organic acid metal salt (II) in the present invention is not particularly limited, but the oil-absorptive cross-linked polymer (I) is 30 to 99.9 parts by weight and organic. The ratio of the acid metal salt (II) is preferably 0.1 to 70 parts by weight. When the amount of the organic acid metal salt (II) is less than 0.1 part by weight, the particles of the oil-absorbing crosslinked polymer (I) are aggregated with each other, and the oil absorption rate of the obtained oil absorbing agent is reduced, which is not preferable. Further, it is not preferable to use a large amount of the organic acid metal salt (II) in an amount exceeding 70 parts by weight, because the oil absorption amount of the oil absorbent and the oil retaining performance are deteriorated.

The oil absorbing agent thus obtained can be used in various forms. For example, a granular oil-absorbing agent may be used as it is by adding or sprinkling it to an oil-water mixed system such as an oil-water suspension or an aqueous solution in which oil is dissolved, or oil, or after being filled in an open container such as a cylindrical tube. Good. Further, the oil absorbing agent of the present invention may be granulated with a binder if necessary, attached to or contained in a fiber, or filled in a cloth bag or a porous package for use.

Further, the oil absorbent may be used in combination with conventionally known oil absorbents and fillers such as chaff, straw, pulp, cotton, porous lime, porous silica, porous pearlite, polypropylene fiber and the like. You can also

[0029]

EXAMPLES Next, the present invention will be described in detail with reference to examples, but the present invention is not limited thereto. In the examples, parts represent parts by weight unless otherwise specified.

[0030]

Example 1 A 500 ml flask equipped with a thermometer, a stirrer, a gas inlet tube, and a reflux condenser was charged with polyoxyethylene alkyl ether (manufactured by Nippon Shokubai Co., Ltd., trade name: Sophthanol 150, which is also used in the following examples. 3 parts (commercially used) were dissolved in 300 parts of water and charged, and the inside of the flask was replaced with nitrogen while stirring and heated to 40 ° C. under a nitrogen stream. Then, 99.794 parts of nonylphenyl acrylate (SP value: 8.3) as the monomer (A), 0.206 parts of 1,6-hexanediol diacrylate as the crosslinkable monomer (B), and a polymerization initiator. Was added to the flask all at once, and the mixture was vigorously stirred under the condition of 750 rpm.

Then, the temperature inside the flask was raised to 80 ° C. and maintained at the same temperature for 2 hours to carry out the polymerization reaction. Then, the temperature inside the flask was further raised to 90 ° C. and maintained for 2 hours to complete the polymerization. By doing so, an aqueous dispersion containing the oil-absorptive cross-linked polymer (1) having an average particle diameter of 30 μm (resin content 25% by weight)
Got

After melting 9.343 parts of stearic acid at 80 ° C., it was gradually added to 120 parts of an aqueous dispersion containing the oil-absorptive crosslinked polymer (1) obtained by the previous polymerization while stirring. . Then, the temperature was raised to 90 ° C. and calcium hydroxide was added to 1.
An aqueous dispersion consisting of 276 parts and 40 parts of water was gradually added, and then stirring was continued for 2 hours to complete the reaction. The reaction product solution thus obtained is dried in an oil bath at 105 ° C. with stirring to obtain a granular oil absorbent (1) containing 30 parts of the oil-absorbing crosslinked polymer (1) and 10 parts of calcium stearate. Obtained.

[0033]

Example 2 Hexadecyl methacrylate (SP value: 7.8) 49.93 as the monomer (A) in Example 1.
0 part and N-octyl methacrylamide (SP value:
8.6) 49.930 parts, divinylbenzene O.V. as the crosslinkable monomer (B). By the same method as in Example 1 except that 140 parts were used instead and the number of revolutions was changed to 200 rpm, an aqueous dispersion containing the oil-absorbing crosslinked polymer (2) having an average particle diameter of 300 μm (resin content 25 wt. %) Was obtained.

12-Hydroxystearic acid 9.404
After being melted under conditions of 80 ° C., it was gradually added to 360 parts of an aqueous dispersion containing the oil-absorptive crosslinked polymer (2) obtained by the previous polymerization while stirring. Then, the temperature was raised to 90 ° C., an aqueous dispersion consisting of 1.218 parts of calcium hydroxide and 40 parts of water was gradually added, and then stirring was continued for 2 hours to complete the reaction. The obtained reaction product liquid is dried in an oil bath at 105 ° C. while being stirred to give 90 parts of an oil-absorbing crosslinked polymer (2) and 10 parts of calcium 12-hydroxystearate as a granular oil absorbing agent ( 2) was obtained.

[0035]

Example 3 Dodecyl acrylate (SP value: 7.9) 57.7 as a monomer (A) in an aqueous solution prepared by dissolving 3 parts of the polyoxyethylene alkyl ether in 300 parts of water.
72 parts and N, N-dioctyl acrylamide (SP
Value: 8.2) 38.515 parts, polypropylene glycol dimethacrylate (molecular weight 4000) as the crosslinkable monomer (B) 3.713 parts, and as the polymerization initiator 2,2
′ -Azobisisobutyronitrile O. A solution consisting of 5 parts was added and mixed with a homomixer at 10,000 rpm for 10 minutes to obtain an aqueous dispersion of a monomer.

Then, an aqueous dispersion of the above monomer was charged into a 500 ml flask equipped with a thermometer, a stirrer, a gas introduction tube and a reflux condenser, and the inside of the flask was replaced with nitrogen while vigorously stirring under the conditions of 400 rpm. did. Subsequently, the temperature inside the flask was raised to 70 ° C. under a nitrogen stream, the polymerization temperature was maintained for 2 hours to carry out the polymerization reaction, and then the temperature was further raised to 90 ° C. to complete the polymerization, and the oil absorption with an average particle diameter of 5 μm was obtained. An aqueous dispersion (resin pure content: 25% by weight) containing the crosslinkable polymer (3) was obtained.

After melting 8.634 parts of lauric acid under the condition of 80 ° C., it was gradually added to 60 parts of an aqueous dispersion containing the oil-absorptive crosslinked polymer (3) obtained in the previous polymerization while stirring. . Then, the temperature was raised to 90 ° C., an aqueous dispersion consisting of 2.249 parts of zinc hydroxide and 40 parts of water was gradually added, and stirring was continued for 2 hours to complete the reaction. The reaction product solution obtained is 1
By drying in an oil bath at 05 ° C with stirring, a granular oil absorbent (3) containing 15 parts of the oil-absorbing crosslinked polymer (3) and 10 parts of zinc laurate was obtained.

[0038]

Example 4 99.823 parts of dodecyl acrylate (SP value: 7.9) as the monomer (A) in Example 1,
A water dispersion containing an oil-absorbing crosslinked polymer (4) having an average particle diameter of 30 μm was prepared by the same method as in Example 1 except that 0.177 part of ethylene glycol diacrylate was used as the crosslinkable monomer (B) instead. A body (resin pure content 25% by weight) was obtained.

After melting 9.343 parts of stearic acid under the condition of 80 ° C., it was gradually added to 120 parts of an aqueous dispersion containing the oil-absorptive crosslinked polymer (4) obtained by the previous polymerization while stirring. . Then, the temperature was raised to 90 ° C. and calcium hydroxide was added to 1.
An aqueous dispersion consisting of 276 parts and 40 parts of water was gradually added, and then stirring was continued for 2 hours to complete the reaction. The reaction product solution thus obtained is dried in an oil bath at 105 ° C. with stirring to obtain a granular oil absorbent (4) containing 30 parts of the oil-absorbing crosslinked polymer (4) and 10 parts of calcium stearate. Obtained.

[0040]

Example 5 In Example 1, t- was used as the monomer (A).
54.881 parts of butylstyrene (SP value: 7.9) and 44.903 parts of 1-decene (SP value: 7.0), 0.216 parts of divinylbenzene as the crosslinkable monomer (B) were used instead. A water dispersion containing the oil-absorbing crosslinked polymer (5) (resin content of 25% by weight) was obtained by the same method as in Example 1 except for the above. Then, the solid content was separated from the aqueous dispersion by filtration, dried and pulverized with a colloid mill to obtain granular oil-absorbing crosslinked polymer (5) having an average particle size of 5 μm.

After dissolving 1 part of the same polyoxyethylene alkyl ether as used in Example 1 in 100 parts of water, 8
A liquid obtained by melting 9.628 parts of stearic acid under the condition of 80 ° C. was mixed with the aqueous solution heated to 0 ° C. to obtain an emulsion of stearic acid. To this emulsion, 30 parts of granules of the oil-absorbent crosslinked polymer (5) obtained by the previous polymerization was gradually added with stirring. Then, the temperature was raised to 90 ° C., an aqueous dispersion consisting of 1.726 parts of basic magnesium carbonate and 40 parts of water was gradually added, and stirring was continued for 2 hours to complete the reaction. The reaction product solution thus obtained is dried in an oil bath at 105 ° C. with stirring to dry the oil-absorbing crosslinked polymer (5) 3
A granular oil absorbent (5) containing 0 part and 10 parts of magnesium stearate was obtained.

[0042]

Example 6 Nonylphenyl acrylate (SP value: 8.3) 74.79 as the monomer (A) in Example 1.
3 parts and hydroxyethyl acrylate (SP value: 1
0.3) The same method as in Example 1 except that 24.931 parts was used instead and the amount of 1,6-hexanediol diacrylate as the crosslinkable monomer (B) was changed to 0.276 parts. Thus, an aqueous dispersion (resin content of 25% by weight) containing the oil-absorbent crosslinked polymer (6) having an average particle diameter of 30 μm was obtained.

After melting 7.350 parts of stearic acid under the condition of 80 ° C., it was gradually added to 120 parts of an aqueous dispersion containing the oil-absorptive crosslinked polymer (6) obtained in the previous polymerization while stirring. . Then, the temperature was raised to 90 ° C., an aqueous dispersion consisting of 3.027 parts of lead monoxide and 40 parts of water was gradually added, and then stirring was continued for 2 hours to complete the reaction. The reaction product solution obtained is 1
By drying in an oil bath at 05 ° C with stirring, a granular oil absorbent (6) containing 30 parts of the oil-absorbing crosslinked polymer (6) and 10 parts of lead stearate was obtained.

[0044]

Example 7 In Example 1, 2 parts of sodium stearate was used instead of 3 parts of polyoxyethylene alkyl ether.
Using 5 parts, vinyl laurate (S) as the monomer (A)
P value: 7.9) 99.811 parts, trimethylolpropane triacrylate O.V. as the crosslinkable monomer (B). 18
By the same method as in Example 1 except that 7 parts were used instead, an aqueous dispersion (pure resin content: 25% by weight) containing the oil-absorbing crosslinked polymer (7) having an average particle diameter of 30 μm was obtained.

After 8.077 parts of stearic acid was melted under the condition of 80 ° C., it was gradually added to 120 parts of an aqueous dispersion containing the oil-absorptive crosslinked polymer (7) obtained by the above polymerization while stirring. . Then, the temperature was raised to 90 ° C., an aqueous dispersion consisting of 4.702 parts of barium hydroxide octahydrate and 40 parts of water was gradually added, and then stirring was continued for 2 hours to complete the reaction. The resulting reaction product liquid is dried in an oil bath at 105 ° C. while being stirred to give a granular oil absorbent (7) containing 30 parts of the oil-absorbing crosslinked polymer (7) and 10 parts of barium stearate. Got

[0046]

Comparative Example 1 An average particle diameter of 30 μm was obtained in the same manner as in Example 4 except that the amount of dodecyl acrylate was changed to 94.637 parts and the amount of ethylene glycol diacrylate was changed to 5.363 parts. An aqueous dispersion containing the comparative polymer (1) was obtained.

Then, 30 parts of the comparative polymer (1) and 10 parts of calcium stearate were prepared in the same manner as in Example 4.
A comparative oil absorbent (1) containing 10 parts was obtained.

[0048]

Comparative Example 2 Dodecyl acrylate 9 in Example 4
Instead of the monomer (A) consisting of 9.823 parts, 39.854 parts of dodecyl acrylate and methacrylic acid (SP
Value: 10.1) 59.780 parts were used, and Comparative Polymer (2) having an average particle size of 30 μm was prepared in the same manner as in Example 4 except that the amount of ethylene glycol diacrylate was changed to 0.366 parts. An aqueous dispersion containing it was obtained.

Then, 30 parts of the comparative polymer (2) and 10 parts of calcium stearate were prepared in the same manner as in Example 4.
A comparative oil absorbent (2) containing 1 part was obtained.

[0050]

Comparative Example 3 An aqueous dispersion containing the comparative polymer (3) having an average particle size of 30 μm was obtained by the same method as in Example 4 except that the crosslinkable monomer (B) was not used. It was

Then, 30 parts of Comparative Polymer (3) and 10 parts of calcium stearate were prepared by the same method as in Example 4.
A comparative oil absorbent (3) containing 10 parts was obtained.

[0052]

Comparative Example 4 The aqueous dispersion of the crosslinked polymer (4) obtained in Example 4 was put in a glass petri dish and dried at 100 ° C. for 24 hours to obtain a sheet-shaped comparative oil absorbent (4).

[0053]

[Example 8] Oil absorbing agent (1) obtained in Examples 1-7
(7) and the comparative oil absorbent obtained in Comparative Examples 1 to 4 (1)
Each of 5 g of (4) to (4) was immersed in kerosene at 20 ° C. for 24 hours, and then collected by filtration on a 508 mesh nylon filter cloth. Next, the kerosene that was not absorbed and retained by the oil absorbing agent was wiped off, the weight of the oil absorbing agent was measured, and the saturated absorption amount of kerosene was calculated according to the following formula. The results are shown in Table 1.

Saturated absorption amount (g) = weight of oil absorbent after immersion in kerosene-weight of oil absorbent before immersion in kerosene

[0055]

[Example 9] Oil absorbing agent (1) obtained in Examples 1 to 7
(7) and the comparative oil absorbent obtained in Comparative Examples 1 to 4 (1)
5 g of each of (4) to (4) were weighed into a cylindrical glass test tube having an inner diameter of 20 mm. Then, under the condition of 20 ° C., the kerosene equivalent to half the saturated absorption amount of kerosene obtained in Example 8 was charged into each test tube at a time, and the time until no fluidized kerosene was observed (oil absorption time) Was measured. The results are shown in Table 1.

[0056]

[Table 1]

[0057]

According to the production method of the present invention, it is easy to uniformly and reproducibly coat the surface of a specific oil-absorbing crosslinked polymer with fine powder of an organic acid metal salt, and the resulting granular oil-absorbing agent is obtained. Has a high surface water repellency, so that it can selectively absorb only oil from an oil-water mixed system, has excellent oil retention performance of oil once absorbed, and has a sufficient oil passage to secure oil absorption speed. It will be extremely fast. Furthermore, the oil absorbent obtained by the present invention has a particle size of 1 compared to the conventional oil absorbents.
Even if the particle size is smaller than 00 μm, aggregation of particles is unlikely to occur during oil absorption, so that the high oil absorption capacity originally possessed by the oil-absorptive crosslinked polymer can be efficiently and quickly exhibited.

Therefore, the oil absorbing agent obtained by the present invention is used for the recovery of oil spilled at sea, the recovery of floating oil, the recovery of oil in waste water, the emulsion breaker, the oil leakage treatment agent, the edible waste oil treatment agent, the machine waste oil treatment agent, and the household waste oil treatment agent. Or industrial oil wipes, chemical wipes, oil leak sensors, oil sealants,
It can be applied to a very wide range of applications such as various oil retention agents,
It can also be used as a sustained-release base material for various fragrances, insecticides, fish collecting agents and the like.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display area C08L 31/04 LHD 6904-4J 33/00 LHZ 7921-4J E02B 15/10 B 9231-2D // C08F 220/18 MMC 7242-4J (72) Inventor Toshio Tamura 14-1 Chidoricho, Kawasaki-ku, Kawasaki-shi, Kanagawa Nihon Shokubai Kawasaki Research Institute

Claims (5)

[Claims] 1. A monomer (A) having one polymerizable unsaturated group in a molecule containing a monomer having a solubility parameter (SP value) of 9 or less as a main component in an amount of 96 to 99.999% by weight, and 0.001 to 4% by weight of a crosslinkable monomer (B) having at least two polymerizable unsaturated groups in the molecule (however, the total amount of the monomers (A) and (B) is 100% by weight). An organic carboxylic acid and a metal compound capable of forming a salt by reaction with an organic carboxylic acid in an aqueous medium in the presence of the particulate matter of the oil-absorptive crosslinked polymer (I) obtained by polymerizing the monomer component consisting of A method for producing a granular oil-absorbing agent containing an oil-absorbing crosslinked polymer (I) and an organic acid metal salt (II), which comprises mixing to form an organic acid metal salt (II). 2. The monomer (A) has at least one aliphatic hydrocarbon group having 3 to 30 carbon atoms and is alkyl (meth) acrylate, alkylaryl (meth) acrylate, alkyl (meth) acrylamide. , Alkylaryl (meth) acrylamide, fatty acid vinyl ester,
The method for producing a granular oil absorbent according to claim 1, which comprises at least one unsaturated compound (a) selected from the group consisting of alkylstyrene and α-olefin as a main component. 3. The oil-absorbing crosslinked polymer (I) has an average particle size of 0.
The method for producing a granular oil absorbent according to claim 1, wherein the granular oil absorbent is in the range of 5 to 500 µm. 4. The method for producing a granular oil absorbent according to claim 1, wherein the metal compound is at least one compound selected from the group consisting of oxides, hydroxides, carbonates and basic carbonates. 5. The ratio of the oil-absorbing crosslinked polymer (I) and the organic acid metal salt (II) in the oil-absorbing agent is 3 in the oil-absorbing crosslinked polymer (I).
0 to 99.9 parts by weight of the organic acid metal salt (II) is 0.1 to 7
The method for producing a granular oil absorbent according to claim 1, wherein the amount is 0 part by weight.