JP2758483B2 - Oil absorbing material - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an oil absorbing material.

More specifically, it selectively and efficiently absorbs oil even in oil-water mixed system oil and thin film oil floating on the water surface,
In addition, the present invention relates to an oil absorbing material which is excellent in oil retention performance of absorbed oil, has no oil re-release (liquid dripping, etc.) once absorbed, and has high oil recovery efficiency, and easy post-treatment such as incineration.

(Prior Art) In recent years, recovery of oil spilled to the sea and oil in wastewater has become a major problem in environmental conservation.

Further, there is a strong demand for a simple treatment method for small-scale waste oil discarded in homes and factories and for leakage of machine oil and the like in factories.

As one of the most effective means of recovering these spilled oils and oil in wastewater or treating waste oil and oil leakage, means for absorbing oil with an oil absorbing material and then performing incineration and other post-treatment has been conventionally used. . As such an oil-absorbing material, for example, a synthetic resin-based oil-absorbing material made of a hydrophobic fiber such as a polypropylene fiber, a polystyrene fiber, or a polyethylene fiber or a nonwoven fabric thereof has been used.

However, the conventional synthetic resin-based oil-absorbing material has the following disadvantages because the oil-absorbing action is caused by adsorbing and holding the oil in the voids existing in the oil-absorbing material.

Poor oil retention after oil absorption, practically no oil retention for low-viscosity oils, and re-release of oil that was easily absorbed by viscous oils with a slight external pressure Liquid dripping easily occurs, and post-processing becomes extremely complicated.

When applied to the collection of oil components in oil-water mixtures and thin-film oil floating on the water surface, the oil recovery rate is poor, and a large amount of water is absorbed. Or inconvenience in incineration after recovery.

(Problems to be Solved by the Invention) The present invention is to solve the above-mentioned problems of the conventional oil absorbing material.

That is, an object of the present invention is to selectively and efficiently absorb oil even in an oil-water mixed system oil or a thin film oil floating on the surface of a water, and to exhibit excellent nesting performance of the absorbed oil. Since there is no re-release (liquid dripping, etc.), oil recovery efficiency is high,
Another object of the present invention is to provide an oil-absorbing material that can be easily subjected to post-treatment such as incineration.

(Means and Actions for Solving the Problems) The present inventors supported a crosslinked polymer obtained by polymerizing a specific monomer component on a hydrophobic porous substrate,
The inventors have found that an oil-absorbing material having excellent oil-absorbing performance and oil-retaining performance can be obtained, and have completed the present invention.

That is, the present invention provides a solubility parameter (SP value) of 9
(A) 90 to 99.999% by weight of a monomer having one polymerizable unsaturated group in the molecule and a crosslink having at least two polymerizable unsaturated groups in the molecule. 0.001 to 10% by weight (but monomer (A))
And (B) are 100% by weight.) The oil-absorbing material comprises a crosslinked polymer (I) obtained by polymerizing a monomer component comprising

The solubility parameter (SP value) is generally used as a scale indicating the polarity of a compound. In the present invention, a value derived by substituting Hoy's aggregation energy constant into Small's calculation formula is applied, and the unit (cal) is used. / cm ³ ) expressed as ^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. . It is not preferable to use a monomer having a solubility parameter (SP value) of more than 9 as a main component of the monomer (A) because the oil absorbing performance of the obtained oil absorbing material is significantly reduced.

Monomers having a solubility parameter (SP value) of 9 or less and one polymerizable unsaturated group in the molecule include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, t- Butyl (meta)
Acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate,
Phenyl (meth) acrylate, octylphenyl (meth) acrylate, nonylphenyl (meth) acrylate, dinonielphenyl (meth) acrylate, cyclohexyl (meth) acrylate, menthyl (meth) acrylate, dibutylmaleate, didodecylmaleate, dodecyl Unsaturated carboxylic esters such as crotonate and didodecyl itaconate; (di) butyl (meth)
Acrylamide, (di) dodecyl (meth) acrylamide, (di) stearyl (meth) acrylamide, (di)
(Meth) acrylamide having a hydrocarbon group such as butylphenyl (meth) acrylamide and (di) octylphenyl (meth) acrylamide; 1-hexene, 1-octene, isooctene, 1-nonene, 1-decene, 1-dodecene, etc. Α-olefins; alicyclic vinyl compounds such as vinylcyclohexane; allyl ethers having an aliphatic hydrocarbon group such as dodecyl allyl ether; aliphatic carbonization such as vinyl caproate, vinyl laurate, vinyl palmitate and vinyl stearate. Vinyl esters having a hydrogen group; vinyl ethers having an aliphatic hydrocarbon group such as butyl vinyl ether and dodecyl vinyl ether; and aromatic vinyl compounds such as styrene, t-butyl styrene and octyl styrene. One Alternatively, two or more kinds can be used. Among these, monomers that provide better oil absorption performance and oil retention performance include at least one carbon atom having 3 carbon atoms.
Having up to 30 aliphatic hydrocarbon groups, and alkyl (meth)
A main component is at least one unsaturated compound (a) selected from the group consisting of acrylate, alkylaryl (meth) acrylate, alkyl (meth) acrylamide, alkylaryl (meth) acrylamide, alkylstyrene and α-olefin. Monomer (A)
Is particularly preferred.

The amount of such a monomer having a solubility parameter (SP value) of 9 or less in the monomer (A) is as follows.
Is at least 50% by weight, more preferably at least 70% by weight, based on the total amount of Solubility parameter (SP value)
Is 50% by weight in the monomer (A) of the monomer having a content of 9 or less.
If it is less than 1, only an oil-absorbing material having poor oil-absorbing performance and oil-retaining performance can be obtained.

Therefore, in the present invention, a monomer having a solubility parameter (SP value) of 9 or less must be contained in the monomer (A) in an amount of 50% by weight or more. % Of a monomer having a solubility parameter (SP value) exceeding 9 at a ratio of not more than 9%. Examples of such a monomer include (meth) acrylic acid, acrylonitrile, maleic anhydride, fumaric acid, hydroxyethyl (meth) acrylate, polyethylene glycol (meth) acrylate,
Mexipolyethylene glycol (meth) acrylate and the like can be mentioned.

Examples of the crosslinkable monomer (B) used in the present invention include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and polyethylene glycol-polypropylene glycol (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, tetramethylolmethanetetra (meth) acrylate, alkylene oxide adducts of polyhydric alcohols (for example, glycerin, trimethylolallopane or tetramethylolmethane) and (meth) acrylic Examples thereof include polyfunctional (meth) acrylates and divinylbenzene obtained by esterification with an acid, and one or more of these crosslinkable monomers can be used.

The ratio of the monomer (A) and the crosslinkable monomer (B) in the monomer components used in producing the crosslinked polymer (I) is determined by the ratio of the monomer (A) and the crosslinkable monomer. The monomer (A) is in the range of 90 to 99.999% by weight, and the crosslinkable monomer (B) is in the range of 0.001 to 10% by weight, based on the total of (B).

If the amount of the monomer (A) is less than 90% by weight or the amount of the crosslinkable monomer (B) exceeds 10% by weight, the crosslinked density of the resulting crosslinked polymer becomes too high to absorb a large amount of oil. Therefore, it is not preferable. When the amount of the monomer (A) exceeds 99.999% by weight or the amount of the crosslinkable monomer (B) is less than 0.001% by weight,
The solubility of the obtained crosslinked polymer in oil is increased, and the crosslinked polymer is desorbed and eluted from the hydrophobic porous substrate after oil absorption, so that the oil absorbing material cannot perform its original function, which is not preferable.

In order to produce the crosslinked polymer (I), the monomer component is copolymerized using a polymerization initiator by a known method such as suspension polymerization or bulk polymerization to obtain a crosslinked polymer, and if necessary, Operations such as pulverization and molding may be added to adjust the particle size and shape to be suitable for supporting on a hydrophobic porous substrate. Above all, it is easy to remove heat of reaction and it is easy to obtain a granular cross-linked polymer suitable for obtaining a large oil-absorbing material having a high oil-absorbing rate.
It is preferably produced by suspension polymerization.

Suspension polymerization, for example, using an emulsifier having a high HLB value, a protective colloid agent such as polyvinyl alcohol, hydroxyethyl cellulose, gelatin, and the like, suspending the monomer components in water, in the presence of an oil-soluble polymerization initiator The polymerization may be carried out. Examples of the polymerization initiator include organic peroxides such as benzoyl peroxide, lauroyl peroxide and cumene hydroperoxide, 2,2'-azobisisobutyronitrile, and 2,2'-azobisdimethylvaleronitrile. An azo compound or the like can be used, and the polymerization temperature is 50 to
A range of 150 ° C. is preferred. The resulting aqueous suspension of the finely divided resin having a particle size of about 10 to 1000 μm is overdried to obtain the desired crosslinked polymer (I).

In addition, the crosslinked polymer (I) was not separated from the aqueous suspension of the crosslinked polymer (I) obtained by the suspension polymerization, and the aqueous suspension was applied to a hydrophobic porous substrate as described below. Thus, the oil absorbing material of the present invention can be obtained.

As the hydrophobic porous substrate used in the present invention, a crosslinked polymer having hydrophobicity such that it does not itself dissolve or swell in water, and preferably has high lipophilicity to adsorb oil, and There is no particular limitation as long as it is a porous substrate having a large surface area capable of effectively supporting (I) and a void for absorbing and retaining oil. For example, a substrate composed of synthetic fibers or lipophilic natural fibers may be used. it can. Above all, a nonwoven fabric or woven fabric made of at least one synthetic resin selected from the group consisting of polyolefins such as polypropylene and polyethylene, polyester, nylon and polyurethane is provided as an oil absorbing material having particularly excellent oil absorbing performance. Is preferred.

The oil absorbing material of the present invention is obtained by supporting the crosslinked polymer (I) on a hydrophobic porous substrate.

Therefore, the method for producing the oil-absorbing material of the present invention is not particularly limited as long as the crosslinked polymer (I) can be supported and fixed on the hydrophobic porous substrate to such an extent that it does not detach from the hydrophobic porous substrate during use. For example, a method in which the crosslinked polymer (I) is sandwiched between hydrophobic porous substrates, a method in which a mixture of the crosslinked polymer (I) and a hydrophobic fiber or its fleece is formed into a sheet and the crosslinked polymer (I) For dispersing and fixing in a porous substrate, a method for bonding and fixing a crosslinked polymer (I) to a hydrophobic porous substrate using an adhesive, and a monomer for forming a crosslinked polymer (I) by polymerization A method in which the components are impregnated in a hydrophobic porous substrate, and then the monomer component is polymerized on the hydrophobic porous substrate to form a crosslinked polymer (I) on the hydrophobic porous substrate and fixed. And the like.

Among them, as a preferred method of supporting the crosslinked polymer (I) on the hydrophobic porous substrate, an aqueous suspension of the crosslinked polymer (I) obtained by the above suspension polymerization is coated on the hydrophobic porous substrate. And then applying vibration as necessary to uniformly disperse them in the hydrophobic porous substrate, followed by drying. Further, for the purpose of strengthening the support, the support may be impregnated with an adhesive after the support to bond the crosslinked polymer (I) and the hydrophobic porous material to the base material. Further, as a more preferable method, a method of mixing a hydrophobic fiber such as polyolefin or a fleece thereof with a crosslinked polymer (I), and then forming a sheet according to a general nonwoven fabric manufacturing method such as needle punching or spunbonding. There is.

Further, as a preferable method of supporting the crosslinked polymer (I) on the hydrophobic porous substrate, a method of impregnating the monomer component into the hydrophobic porous substrate and then polymerizing the monomer on the substrate is used. There is. In this method, the monomer component is impregnated into the hydrophobic porous base material by spraying the mixed solution obtained by adding the polymerization initiator to the monomer component onto the base material by using a spray, brush coating, a roller or a screen. Or by immersing the base material in the mixed solution and squeezing the base material to a predetermined amount as necessary. Also,
In order to polymerize the monomer on the substrate, the substrate to which the monomer component has adhered may be heated or irradiated with ultraviolet rays. According to this method, the crosslinked polymer (I) generated by polymerization is in a state of being uniformly coated on the surface of the hydrophobic porous substrate, and the surface area of the crosslinked polymer (I) can be extremely widened. , Can accelerate oil absorption. In addition, leakage and desorption of the crosslinked polymer (I) from the hydrophobic porous substrate are reduced.

The amount of the crosslinked polymer (I) supported on the hydrophobic porous substrate in the oil-absorbing material of the present invention is not particularly limited, but the crosslinked polymer (I) is added to 100 parts by weight of the hydrophobic porous substrate. 10-5
The ratio is preferably in the range of 00 parts by weight. If the amount of the crosslinked polymer (I) carried is less than 10 parts by weight, the oil absorption performance and oil retention performance may be insufficient, which is not preferable. Also, when the crosslinked polymer (I) is supported in a large amount exceeding 500 polymerization parts, the crosslinked polymer (I) fills the voids of the hydrophobic porous substrate, and the oil absorbing performance of the oil absorbing material is reduced. Is not preferred.

(Effect of the Invention) Since the oil-absorbing material of the present invention has a crosslinked polymer obtained by polymerizing a specific lipophilic monomer component supported on a hydrophobic porous substrate, the hydrophobic porous substrate Has an oil-absorbing action in which the cross-linked polymer further absorbs the adsorbed oil and swells.
It has excellent oil-absorbing performance of the following (1) as compared with conventional oil-absorbing materials.

It has excellent oil retention after oil absorption, and is extremely easy to perform post-treatment without causing liquid dripping.

Since it absorbs almost no water and selectively absorbs only oil, it is highly effective in recovering oil from a mixed oil / water system or thin film oil floating on the water surface.

Accordingly, the oil-absorbing material of the present invention can be used for household waste oil treatment, industrial waste oil treatment, oil leakage treatment, wastewater treatment, pits,
It is extremely effective in applications such as treating floating oil spilled to harbors, lakes and the sea.

(Examples) Next, the present invention will be described in detail with reference to examples and comparative examples, but the present invention is not limited thereto. Unless otherwise specified in the examples, parts are parts by weight.

Example 1 Nonylphenyl acrylate (SP value: 8.3) 99.794 as a monomer (A) in a stainless steel bucket having a capacity of 1.9.
, A solution consisting of 0.206 parts of 1,6-hexanediol diacrylate as a crosslinkable monomer (B) and 0.5 parts of benzoyl peroxide as a polymerization initiator.

Then, a polypropylene nonwoven fabric (basis weight: 200 g / m ² , bulk density: 0.1 g / cm ³ ) cut to 20 cm × 15 cm was immersed in the solution, pulled up, and squeezed by a simple roller. Thereafter, the polypropylene nonwoven fabric to which the monomer solution is adhered is placed in a warm air drier kept at 80 ° C. under a nitrogen atmosphere, heated at 80 ° C. for 2 hours, and then heated to 90 ° C. and maintained at the same temperature for 2 hours. Then, polymerization was carried out. Thus, the oil absorbing agent (1) of the present invention in which the crosslinked polymer (I) produced by the polymerization was carried on the polypropylene nonwoven fabric was obtained. At this time, the amount of the crosslinked polymer (I) carried on the polypropylene nonwoven fabric was 100 parts by weight relative to 100 parts of the nonwoven fabric.

Example 2 In Example 1, 49.930 parts of hexadecyl methacrylate (SP value: 7.8) and 49.930 parts of N-octyl methacrylamide (SP value: 8.6) as monomer (A), and divinylbenzene as crosslinkable monomer (B) An oil-absorbing material (2) was obtained in the same manner as in Example 1 except that 0.140 part was used instead. At this time, the amount of the crosslinked polymer (I) carried on the polypropylene nonwoven fabric was 100 parts by weight relative to 100 parts of the nonwoven fabric.

Example 3 In Example 1, 55.704 parts of dodecyl acrylate (SP value: 7.9) and 37.136 parts of N, N-dioctylacrylamide (SP value: 8.2) as the monomer (A), and polypropylene as the crosslinkable monomer (B) An oil-absorbing material (3) was obtained in the same manner as in Example 1 except that 7.160 parts of glycol dimethacrylate (molecular weight 4000) was used instead. At this time, the amount of the crosslinked polymer (I) carried on the polypropylene nonwoven fabric was 100 parts by weight relative to 100 parts of the nonwoven fabric.

Example 4 Example 1 was repeated except that 99.823 parts of dodecyl acrylate (SP value: 7.9) was used as the monomer (A) and 0.177 parts of ethylene glycol diacrylate was used as the crosslinkable monomer (B) in Example 1. An oil-absorbing material (4) was obtained in the same manner as in (1). At this time, the amount of the crosslinked polymer (I) carried on the polypropylene nonwoven fabric was 100 parts by weight relative to 100 parts of the nonwoven fabric.

Example 5 In Example 1, as monomer (A), 54.881 parts of t-butylstyrene (SP value: 7.9) and 1-decene (SP value:
7.0) An oil absorbing material (5) was obtained in the same manner as in Example 1 except that 44.903 parts of divinylbenzene was used instead of the crosslinkable monomer (B), and 0.216 part of divinylbenzene was used. The amount of the crosslinked polymer (I) supported on the polypropylene nonwoven fabric at this time is
The ratio was 100 parts to 100 parts.

Example 6 In Example 1, 74.793 parts of nonylphenyl acrylate (SP value: 8.3) and 24.931 parts of hydroxyethyl acrylate (SP value: 10.3) as the monomer (A), and 1 as the crosslinkable monomer (B) An oil-absorbing material (6) was obtained in the same manner as in Example 1, except that 0.276 parts of 1,6-hexanediol diacrylate was used instead. At this time, the amount of the crosslinked polymer (I) supported on the polypropylene nonwoven fabric was
The ratio was 100 parts to 0 parts.

Example 7 Polyester nonwoven fabric (basis weight 200 g / m ² , bulk density 0.1 g / cm ³ ) instead of polypropylene nonwoven fabric in Example 4
With the exception that the amount of the crosslinked polymer (I) carried on the polyester nonwoven fabric was 200 parts relative to 100 parts of the nonwoven fabric,
An oil absorbing material (7) was obtained in the same manner as in Example 4.

Example 8 Nylon nonwoven fabric cut to 20 cm x 15 cm (basis weight 200 g / m2)
² , bulk density 0.1 g / cm ³ ), 99.823 parts of dodecyl acrylate (SP value: 7.9) as monomer (A), and 0.177 of ethylene glycol diacrylate as crosslinkable monomer (B)
And a solution consisting of benzoyl peroxide as a polymerization initiator was sprayed uniformly using a spray.

After that, put the nylon non-woven fabric with the monomer solution in a warm air dryer kept at 80 ° C under a nitrogen atmosphere.
After heating at 80 ° C. for 2 hours, the temperature was raised to 90 ° C. and maintained at the same temperature for 2 hours to carry out polymerization to obtain an oil absorbing material (8). The amount of the crosslinked polymer (I) carried on the nylon nonwoven fabric at this time was 50 parts with respect to 100 parts of the nonwoven fabric.

Example 9 A thermometer, a stirrer, a gas inlet tube and a reflux condenser were provided.
Softanol in a 500 ml flask 90 (Nippon Shokubai Chemical
Of secondary alcohols having 12 to 14 carbon atoms manufactured by Kogyo Co., Ltd.
3 parts dissolved in 300 parts water and charged
The atmosphere in the flask was replaced with nitrogen under stirring, and 40 ° C under a nitrogen stream.
Heated. Thereafter, dodecylacrylic acid is used as monomer (A).
Rate (SP value: 7.9) 99.823 parts, as crosslinkable monomer (B)
0.177 parts of ethylene glycol diacrylate, polymerized
Solution consisting of 0.5 parts of benzoyl peroxide as initiator
All at once in a flask, and vigorously shake at 500 rpm.
Stirred.

Then, the temperature in the flask was raised to 80 ° C.
The polymerization reaction was carried out for a period of time, and then the temperature inside the flask was further raised to 90 ° C. and maintained for 2 hours to complete the polymerization, and an aqueous suspension of the crosslinked polymer (I) having a particle size of 1 to 100 μm (resin Minutes:
25% by weight).

12 g of the obtained aqueous suspension of the crosslinked polymer (I) was added to 20 cm × 1
Polypropylene non-woven fabric cut to 5 cm (200 g / m ² basis weight,
An oil-absorbing material (9) was obtained by uniformly spraying to a bulk density of 0.03 g / cm ³ ) using a spray and then drying. The amount of the crosslinked polymer (I) carried on the polypropylene nonwoven fabric at this time was 50 parts with respect to 100 parts of the nonwoven fabric.

Comparative Example 1 Example 1 was repeated except that 89.820 parts of dodecyl acrylate (SP value: 7.9) were used as the monomer (A) and 10.180 parts of ethylene glycol diacrylate were used as the crosslinkable monomer (B). A comparative oil-absorbing material (1) was obtained in the same manner as in Example 1. The amount of the crosslinked polymer carried on the polypropylene nonwoven fabric was 100 parts with respect to 100 parts of the nonwoven fabric.

Comparative Example 2 In Example 1, 39.854 parts of dodecyl acrylate (SP value: 7.9) and methacrylic acid (SP) were used as the monomer (A).
Value: 10.1) A comparative oil-absorbing material (2) was obtained in the same manner as in Example 1 except that 59.780 parts were used and 0.366 part of ethylene glycol diacrylate was used as the crosslinkable monomer (B). The amount of the crosslinked polymer carried on the polypropylene nonwoven fabric was 100 parts with respect to 100 parts of the nonwoven fabric.

Comparative Example 3 In Example 4, except that ethylene glycol diacrylate was not used as the crosslinkable monomer (B),
A comparative oil-absorbing material (3) was obtained in the same manner as in Example 4.
The amount of polymer supported on the polypropylene nonwoven fabric at this time is
The ratio was 100 parts with respect to 100 parts of the polypropylene nonwoven fabric.

Example 10 (Oil-absorbing performance test) The oil-absorbing material (1) of the present invention obtained in Examples 1 to 9
(9), Comparative oil-absorbing materials (1) to obtained in Comparative Examples 1 to 3.
(3) Each of the same polypropylene nonwoven fabrics as used in Example 1 was cut into 10 cm × 10 cm, and each of the cut samples was immersed in kerosene or spindle oil at 20 ° C. After 24 hours, lift the sample and hold it with a clip.Leave it in the air for 30 minutes in a suspended state to allow the oil not held by the sample to flow down sufficiently.Measure the weight of the sample and hold it on the oil absorbing material according to the following formula. The amount of oil (oil absorption) was calculated.

Oil absorption (g) = weight of sample after oil absorption-weight of sample before immersion The results are shown in Table 1.

Example 11 (Oil retention performance test) Each of the oil-absorbed samples obtained in Example 10 was placed on a 200-mesh wire mesh, a load of 10 kg / cm ² was applied to the sample for 1 minute, and the amount of oil flowing out at that time Was measured, and the oil retention after weighting was calculated according to the following equation.

Oil retention rate (%) = {(oil absorption-oil spill) / oil absorption} x 100 (The oil absorption (g) is obtained by the calculation formula in Example 10.) The results are shown in Table 1. Shown in

Example 12 (Floating Oil Recovery Test) Water 30 (water surface area: 1350 cm ² ) was placed in a water tank having a capacity of 36, and 15 g of heavy oil A was further added to the water surface. On this water surface, the oil-absorbing materials (1) to (9) obtained in Examples 1 to 9 and the comparative oil-absorbing materials (1) to (3) obtained in Comparative Examples 1 to 3 and those used in Example 1 were used. A sample obtained by cutting each of the same polypropylene nonwoven fabric into 10 cm × 10 cm was floated for 4 hours and then lifted up, and the floating oil recovery ability was evaluated based on the state of heavy oil A remaining on the paper surface according to the following criteria. Table 2 shows the results.

：: No heavy oil A remains on the water surface.

Δ: Fuel oil A is slightly scattered on the water surface.

X: A heavy oil A remains on the water surface in a considerable amount.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Takayoshi Goto 14-1, Chidori-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside the Kawasaki Research Laboratory of Nippon Shokubai Chemical Co., Ltd. A) JP-A-57-2383 (JP, A) JP-A-57-128769 (JP, A) JP-A-63-221187 (JP, A) JP-A-3-258302 (JP, A) JP-A-4 -15286 (JP, A)

Claims (4)

(57) [Claims] 1. A monomer (A) having at least one polymerizable unsaturated group in a molecule containing at least 70% by weight of a monomer having a solubility parameter (SP value) of 9 or less, and at least two monomers in a molecule. Oil Absorbent Material Having Crosslinked Polymer (I) Obtained by Polymerizing Monomer Component Consisting of Crosslinkable Monomer (B) Having Two Polymerizable Unsaturated Groups in a Hydrophobic Porous Substrate . 2. The monomer has an aliphatic hydrocarbon group having 3 to 30 carbon atoms, and has an alkyl (meth) acrylate, an alkylaryl (meth) acrylate, an alkyl (meth) acrylamide, an alkylaryl (meth) The oil absorbing material according to claim 1, wherein the oil absorbing material is at least one unsaturated compound (a) selected from the group consisting of acrylamide, alkylstyrene, and α-olefin. 3. The oil-absorbing material according to claim 1, wherein the crosslinked polymer (I) has lipophilicity and oil-absorbing property, and swells by oil retention. 4. The oil-absorbing material according to claim 1, wherein the hydrophobic porous substrate is a nonwoven fabric or a woven fabric made of at least one synthetic resin selected from the group consisting of polyolefin, polyester, nylon and polyurethane.