JPH06340705A - Cross-linked water-absorbing resin product - Google Patents

Abstract

PURPOSE:To provide a cross-linked water-absorbing resin product containing an olefinic thermoplastic elastomer, a hydrogenated dienic copolymer, a water- absorbing resin, an inorganic filler, a softening agent, a plasticizer, a cross- linking agent and a cross-linking auxiliary, good in strength and shape retainability, and useful for water-proof sheets, etc. CONSTITUTION:The cross-linked water-absorbing resin product is obtained by mixing and cross-linking (A) 100 pts.wt. of an olefinic thermoplastic elastomer comprising 15-55wt.% of an ethylenic polymer and 85-45wt.% of an ethylene- propylene-diene terpolymer, (B) 10-100 pts.wt. of a hydrogenated diene copolymer, the total amount of the components A and B being 100 pts.wt., (C) 5-95 pts.wt. of a water-absorbing resin, (D) 1-25 pts.wt. of an inorganic filler, (E) 2-50 pts.wt. of a softening agent, (F) 2-50 pts.wt. of a plasticizer, (G) 0.05-5.0 pts.wt. of an organic peroxide cross-linking agent, and (H) 0.10-10.0 pts.wt. of a cross-linking auxiliary such as an alpha,beta-unsaturated carboxylic acid metal salt, a bismaleimide compound and a multifunctional vinylic monomer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-absorbent resin crosslinked product containing a water-swellable polymeric water-absorbing agent and an olefinic thermoplastic elastomer. More specifically, waterproof seals between tunnels and segments for water and sewer construction, joint seal materials for underground cables such as communication cables and telephone lines,
TECHNICAL FIELD The present invention relates to a water-absorbent resin cross-linked body in which a water-absorbent resin is blended with an olefinic thermoplastic elastomer, which is useful for civil engineering such as sealing of outer wall panels of buildings, water-stopping materials for construction work, and anti-condensation materials that also have an earthquake-proof function.

[0002]

2. Description of the Related Art Conventional sealing materials for waterproofing between tunnels and waterworks / sewerage segments have been crosslinked polyacrylates, starch-polyacrylate resins, vinyl alcohol copolymers or anhydrous. A water-swellable composition in which a super absorbent polymer such as a resin obtained by crosslinking a reaction product of a maleic acid copolymer and a basic substance is blended with a diene rubber and vulcanized to form a water-swellable composition is widely used (Japanese Patent Application Laid-Open No. 2004-242242). 57-1
08143, 57-135160, etc.). However, since this water absorbent resin composition requires a vulcanization step, there are problems such as an increase in molding cost and a decrease in productivity.

Further, a water-absorbent resin composition containing a thermoplastic resin containing a highly water-absorbent resin, for example, a water-absorbing polymer finely divided into ethylene-vinyl acetate copolymer or polybutadiene (a lower olefin-maleic anhydride is a urea resin). Or a mixture of melamine resin) (JP-A-55-8424), a composition of chlorinated polyethylene and polyisobutylene, and a super absorbent resin (maleic anhydride-isobutylene copolymer, acrylic acid). -Vinyl alcohol copolymer, etc.) (JP-A-62-106879)
However, the former has a large temperature dependency and has a problem of poor workability due to low water absorption and flexibility, especially in the low temperature, and the latter causes environmental problems such as generation of hydrogen chloride during incineration. There is also a problem above.

Further, a carboxylate-containing water absorbent resin and a glycidyl group-containing olefin are melt-kneaded to form a polyolefin resin composition, or a water-absorbent resin powder, a polyolefin resin pellet and an olefin resin pellet powder are melt-kneaded. To increase the shape retention rate after water absorption (JP-A-63-110226 and JP-A-63-13543).
No. 1) has been proposed, but it is a composite composition based on a thermoplastic polymer, and when water absorption and drying are repeated, the water absorbing agent is gradually lost from the resin composition, so-called gel loss reduction occurs, There is a problem in durability during long-term use, such as reduced water absorption efficiency.

The present inventors have investigated a non-vulcanizing type water-absorbent resin composition based on an olefinic thermoplastic elastomer, and have found that a polyethylene-based polymer and an ethylene-based polymer are used.
A water-absorbent resin in an olefin-based thermoplastic elastomer consisting of a propylene-diene copolymer, a resin composition in which a softening agent and a plasticizer are mixed is excellent in flexibility and moldability, and an inorganic filler is added to each component. In the blended composition, the dispersibility in the composition of the water-absorbent resin becomes good and an excellent water-absorbent resin composition is obtained, and by adding a hydrogenated diene-based copolymer to each of the above components, the water-absorbing power is increased. Improved, excellent in flexibility, water absorption, molding processability, and durability such as prevention of water absorbent resin loss (gel loss) by irradiating the above molded body with ionizing radiation to form a cross-linked structure And applied for patents (Japanese Patent Application Nos. 4-237695, 4-237696, and 4-25).
0666, 4-259056).

A resin composition containing the above-mentioned polyethylene polymer, ethylene-propylene-diene copolymer, olefin thermoplastic elastomer, hydrogenated diene copolymer, water-absorbent resin, inorganic filler, softener and plasticizer. In the composition for irradiating the object with ionizing radiation to build a crosslinked structure,
By changing the accelerating voltage and dose of ionizing radiation, it is possible to obtain a composition in which the crosslinked state is changed.

For example, by gently cross-linking the surface layer using a relatively low accelerating voltage, the effect similar to that of laminating a film on the surface layer can be imparted to prevent gel removal. Further, by setting a relatively high accelerating voltage, the degree of cross-linking between the surface layer and the central layer can be made constant, and thereby, water absorption, strength, gel removal prevention performance, etc. can be well balanced. You can also

[0008] The inventors of the present invention subsequently crosslinked the resin composition with a specific organic peroxide type crosslinking agent and a crosslinking auxiliary agent without relying on ionizing radiation which requires a large-scale apparatus. The present invention has been found out that the entire composition is uniformly crosslinked by selection and use, and a water-absorbent resin crosslinked product having good water absorbency and mechanical strength is obtained.

[0009]

Means for Solving the Problems That is, the present invention relates to (a) 100% by weight of an olefinic thermoplastic elastomer comprising 15 to 55% by weight of a polyethylene polymer and 85 to 45% by weight of an ethylene-propylene-diene copolymer. 10 to 100 parts by weight of the hydrogenated diene-based copolymer (b) to 100 parts by weight, and (c) 5 to 95 parts by weight of the water absorbent resin to 100 parts by weight of the components (a) + (b). , (D) 1 to 25 parts by weight of inorganic filler, (e) 2 to 50 parts by weight of softening agent, (f) 2 to 50 parts by weight of plasticizer, (g) 0.05 to 5.0 of organic peroxide cross-linking agent. And (h) 0.1 to 10.0 parts by weight of one or more crosslinking aids selected from (h) metal salts of α, β-unsaturated carboxylic acids, bismaleimide compounds and polyfunctional vinyl monomers. Characterized by cross-linking a resin composition There is provided an aqueous resin crosslinked.

The crosslinked water absorbent resin of the present invention will be described below. The olefinic thermoplastic elastomer (a) which is the base of the water-absorbent resin crosslinked product of the present invention is a composition comprising a polyethylene polymer (first component) and an ethylene-propylene-diene copolymer (second component). is there. Here, as the polyethylene-based polymer which is the first component, a homopolymer of ethylene, a copolymer of ethylene and propylene or another α-olefin, or a copolymer of ethylene and vinyl acetate, ethyl acrylate, or the like, or these It is possible to use homopolymers of the above, or blends of homopolymers and copolymers. In particular,
Polyethylene and ethylene-vinyl acetate copolymer are preferred.

As polyethylene, the melt index (MI, JISK7210, load 2.16 kg) is 0.01 to 100 g /
It preferably has a density of 0.910 to 0.935 g / cm ³ for 10 minutes.
In addition, polyethylene has about 4 to 20 carbon atoms α
-The thing which copolymerized the olefin to about 20 mol% or less is also included. In addition, an ethylene-vinyl acetate copolymer (E
As VA), a copolymer having a vinyl acetate content of 10 to 30% by weight is preferable, and a vinyl acetate content of 17 to 30% by weight is particularly preferable.
Those in the range of 30% by weight are preferable. Such EVA melt index (190 ℃, 2.16kg load)
Is preferably 15 to 25 g / 10 minutes. As the polyethylene-based polymer, an ethylene-vinyl acetate copolymer (E
VA) is more preferred.

Olefinic thermoplastic elastomer (a)
The second component, ethylene-propylene-diene copolymer (EPDM), is a copolymer composed of ethylene, propylene and a diene.

Examples of the diene compound include ethylidene norbornene, 1,4-hexadiene and dicyclopentadiene. The EPDM has an ethylene content of 50 to 60 mol% and a propylene content of 20 to 30.
Those having a mol%, a diene compound content of 1 to 20 mol% and an iodine value of 1 to 30 are preferable. Mooney viscosity (ML _{1 + 4} , 100 ° C) of EPDM is 20-100
Is preferable, and 50 to 90 is particularly preferable.

The blending ratio of the polyethylene polymer and the ethylene-propylene-diene copolymer (EPDM) is 15 to 55% by weight, preferably 20 to 50% by weight, and 85 to 45% by weight EPDM. %, Preferably 80 to 50% by weight. If the polyethylene polymer is less than 15% by weight, the mechanical strength and moldability will decrease, while if the polyethylene polymer exceeds 55% by weight, the hardness will increase and the tear strength will decrease.

Olefinic thermoplastic elastomer (a)
Is produced by melt-kneading the polyethylene polymer and EPDM in the above proportions. That is, 15 to 55% by weight of the polyethylene polymer and 85 to 45% by weight of EPDM are kneaded by a kneading machine such as a twin-screw extruder, a single-screw extruder, a roll kneader, a Banbury mixer, and a Brabender. The kneading temperature may be appropriately set at a temperature at which the resin component serving as the base is melted or higher, but it is usually preferably in the range of 90 to less than 160 ° C. The melt index (1 of the olefinic thermoplastic elastomer composition thus obtained is
90 ° C., 2.16 kg load) is preferably 0.5 to 20 g / 10 minutes.

In the present invention, the olefinic thermoplastic elastomer (a) is a polyethylene polymer and EPDM.
And hydrogenated diene copolymer (b), water-absorbent resin component (c), inorganic filler (d), softening agent (e), plasticizer (f), organic peroxide It can also be prepared by kneading with the system crosslinking agent (g) and the crosslinking aid (h) all at once or in any order.

In the present invention, the hydrogenated diene-based copolymer (b) is blended in order to improve the water absorption of the water-absorbent resin crosslinked product. The hydrogenated diene-based copolymer comprises a vinyl aromatic compound polymer block (A) and a conjugated diene-based polymer or a vinyl aromatic compound and a random copolymer block (B) of a conjugated diene (A). -(B) a block copolymer, or (A)-(B)-(C) consisting of a vinyl aromatic compound and a tapered block (C) in which the vinyl aromatic compound among the conjugated dienes gradually increases. ) A block copolymer or a (A)-(B)-(A) block copolymer comprising a vinyl aromatic polymer (A), which is hydrogenated to obtain at least a double bond of a conjugated diene moiety. It is 80% saturated and has a number average molecular weight of 50,000 to 600,000. These are disclosed in JP-A-3-72512. The hydrogenated diene-based copolymer has a bound styrene content of 10 to 30% by weight and a melt flow rate (2
30 ° C., 2.16 kg load) 3 to 6 g / 10 minutes is preferable. The blending amount of the hydrogenated diene copolymer is the same as that of the component (a).
It is 10 to 100 parts by weight with respect to 100 parts by weight. If the blending amount is less than 10 parts by weight, the improvement of the water absorption of the composition is insufficient, and if it exceeds 100 parts by weight, the weight retention rate decreases.

As the water-absorbent resin (c) in the crosslinked water-absorbent resin of the present invention, those commercially available as superabsorbent resins can be used without any particular limitation, but a carboxyl group or a group capable of being derivatized to a carboxyl group can be used. A highly water-absorbent resin obtained by crosslinking a polymer containing one or two α, β-unsaturated compounds in the molecule as a monomer component with a crosslinking agent is preferable, and among them, the particle size is 5 to 5. 30 μm,
It is preferably 10 to 20 μm.

Examples of such water-absorbent resins include polyacrylate-based resins, starch-acrylate-grafted polymers, vinyl acetate copolymers, maleic anhydride copolymers and vinyl alcohol-based copolymers. Named
Above all, a polyacrylate resin can be preferably used. The water-absorbent resin has a water absorption rate of 10 to 5 of its own weight.
It is desirable to have a water absorption capacity of 00 times, preferably 50 to 200 times. The blending amount of the water absorbent resin is the same as that of the component (a).
The amount is 5 to 95 parts by weight, preferably 30 to 60 parts by weight, based on 100 parts by weight of + (b). If the amount is less than 5 parts by weight, the water absorption of the composition will be insufficient, and if it exceeds 95 parts by weight, the mechanical strength of the composition will decrease.

In the water-absorbent resin crosslinked product of the present invention, the use of the inorganic filler (d) improves the dispersibility of the water-absorbent resin in the composition. Therefore, a compatibilizer may not be used. . Here, as the inorganic filler (d),
Talc, calcium carbonate, gypsum, carbon black, clay, kaolin, silica, diatomaceous earth, magnesium carbonate, barium carbonate, magnesium sulfate, barium sulfate, calcium sulfate, calcium phosphate, aluminum hydroxide, zinc oxide, magnesium hydroxide, calcium oxide, Magnesium oxide, titanium oxide, alumina, mica, shirasu balloon, zeolite, clay silicate, cement, silica fume, mica powder, etc. can be used,
Among them, talc, calcium carbonate and silica are preferable. These inorganic fillers can be used in various shapes such as powder, sphere and flake. The addition amount of the inorganic filler is 1 to 25 parts by weight, preferably 3 to 15 parts by weight, relative to 100 parts by weight of the components (a) + (b). If the addition amount is less than 1 part by weight, the dispersibility of the water absorbent resin will be lowered and the water absorption will be insufficient, and if it exceeds 25 parts by weight, the flexibility will be lowered and the loss of the water absorbent resin will be increased.

In the crosslinked water-absorbent resin of the present invention, a softening agent (e) and a plasticizer (f) are blended in order to improve flexibility at low temperature, powderiness and workability. As the softening agent (e), a mineral oil-based softening agent is preferably used. Examples of the mineral-based softening agent include petroleum-based softening agents such as paraffin-based, naphthene-based and aromatic-based, polymerized high-boiling strong aromatic oil, liquid paraffin, white oil, etc., but preferably petroleum-based softening agent A paraffinic petroleum softener having a good compatibility with an agent, particularly EPDM can be preferably used. The amount of the softening agent added is 2 to 50 parts by weight, preferably 30 to 45 parts by weight, based on 100 parts by weight of the components (a) + (b). If the amount added is less than 2 parts by weight, the flexibility is insufficient, and if it exceeds 50 parts by weight, moldability becomes poor.

As the plasticizer (f), those generally used in resin compositions can be used, and for example, a phthalic acid derivative can be preferably used. As a phthalic acid derivative,
Dimethyl phthalate, di- (2-ethylhexyl) phthalate, diethyl phthalate, dibutyl phthalate, di-n-octyl phthalate, diisooctyl phthalate, diisobutyl phthalate, diheptyl phthalate,
Diphenyl phthalate, diisodecyl phthalate, ditridecyl phthalate, diundecyl phthalate, benzyl phthalate, butyl benzyl phthalate, dinonyl phthalate, alkyl benzyl phthalate, dimethoxy ethyl phthalate, dimethyl cyclohexyl phthalate,
Examples thereof include methylphthalylethyl glycolate, ethylphthalylethyl glycolate, butylphthalylbutyl glycolate and the like, and a mixture thereof. The addition amount of the plasticizer is 2 to 50 parts by weight based on 100 parts by weight of the components (a) + (b). If the amount added exceeds 50 parts by weight, the kneading operation becomes difficult.

In the water absorbent resin cross-linked product of the present invention, an organic peroxide type cross-linking agent (g) and a cross-linking aid (h) are blended in order to introduce a cross-linking structure. The organic peroxide-based crosslinking agent (g) is
Those that decompose appropriately under the temperature conditions for kneading the constituent components of the composition, specifically, a one-minute half-life temperature of 100 to 200 ° C.
Something is preferable. Particularly, when EVA is used as the polyethylene-based polymer, the one-minute half-life temperature is 12
It preferably has a temperature of about 0 to 160 ° C.

Examples of such organic peroxide type crosslinking agents include dialkyl type, ketal type, diacyl type, ketone type, carbonate type and ester type. Specifically, as the dialkyl type, for example, dicumyl peroxide, di-t-butyl peroxide, 2,5-
Examples thereof include dimethyl-2,5-bis (t-butylperoxy) hexane and 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3. Examples of ketals include 1,2 1-bis (t-butylperoxy)-
3,3,5-trimethylcyclohexane, n-butyl-
4,4-bis (t-butylperoxy) valerate,
1,1-bis (t-butylperoxy) cyclohexane, 2,2-bis (t-butylperoxy) butane and the like can be mentioned. Examples of the diacyl-based compound include benzoyl peroxide, p-chlorobenzoyl peroxide, and the like.
2,4-dichlorobenzoyl peroxide and the like, ketone-based compounds such as methyl ethyl ketone peroxide and cyclohexanone peroxide, and carbonate-based compounds such as t-butyl peroxyisopropyl carbonate and di (3-methyl). -3-Methoxybutyl) peroxydicarbonate and the like, and examples of the ester system include cumyl peroxy neodecanoate, t-hexyl peroxy neodecanoate and the like. Among these, those having a one-minute half-life temperature of about 140 to 160 ° C. are particularly preferably used.

The amount of the organic peroxide cross-linking agent is 0.05 to 5.0 parts by weight, preferably 0.1 to 0.3 parts by weight, based on 100 parts by weight of the components (a) + (b). Compounding amount is 0.
If the amount is less than 05 parts by weight, the crosslinking will not be sufficiently carried out and the mechanical strength and durability will be deteriorated, resulting in gel omission. On the other hand, if it exceeds 5.0 parts by weight, the decomposition reaction of the composition precedes, which causes smoke and foul odor.

The crosslinking aid (h) is selected from metal salts of α, β-unsaturated carboxylic acids, bismaleimide compounds and polyfunctional vinyl monomers. The metal salt of α, β-unsaturated carboxylic acid is a salt of α, β-unsaturated carboxylic acid neutralized with a metal ion derived from a metal oxide, a metal chloride, a carbonic acid metal salt, or the like. . Examples of the α, β-unsaturated carboxylic acid that forms the substrate of this metal salt include acrylic acid,
Methacrylic acid, crotonic acid, isocrotonic acid, fumaric acid, maleic acid, etc. may be mentioned, with acrylic acid and methacrylic acid being preferred. Examples of the metal forming a salt by neutralizing the α, β-unsaturated carboxylic acid exemplified above include lithium, sodium, potassium, monovalent metals such as cesium, magnesium, calcium, strontium, barium, and copper. Divalent metals such as zinc may be mentioned.
Of these, divalent metals are preferable, and zinc is particularly preferable.

As the bismaleimide compound, N,
N'-m-phenylene bismaleimide is preferably used, and divinylbenzene is preferably used as the polyfunctional vinyl monomer. These crosslinking aids are used alone or in combination of two or more. The blending amount of the cross-linking aid cannot be generally specified depending on the type of the cross-linking aid, but it is used in the range of 0.1 to 10.0 parts by weight with respect to 100 parts by weight of the components (a) + (b). Also,
In the present invention, in addition to the above components, if desired, further,
An ultraviolet absorber, a heat stabilizer, a light stabilizer, a flame retardant, an antistatic agent, a nucleating agent, a colorant and the like can be appropriately added.

The method for producing a crosslinked water-absorbent resin of the present invention includes olefinic thermoplastic elastomer component (a),
Hydrogenated diene-based copolymer (b), water-absorbent resin component (c),
The inorganic filler (d), the softening agent (e), the plasticizer (f), the organic peroxide-based crosslinking agent (g) and the crosslinking aid (h) are well dispersed, and the organic peroxide-based crosslinking agent is appropriate. Any method may be used as long as it is decomposed into a mixture and the crosslinking reaction proceeds. For example, the above components are kneaded with a single screw extruder, a twin screw extruder, a Banbury mixer, a kneading roll, a brabender, a kneader ruder, or the like. It can be carried out by melt-kneading using a machine and then crosslinking.

The kneading can be carried out in any order, but in order to improve the uniform dispersibility of the water absorbent resin in the composition, an olefinic thermoplastic elastomer component prepared in advance from a polyethylene polymer and EPDM is used. It is preferable that (a) and the water-absorbent resin (b) are premixed by using a stirrer such as a Henschel mixer. The kneading temperature may be appropriately set to a temperature above the melting temperature of the base resin component and to a temperature range in which the organic peroxide-based cross-linking agent is appropriately decomposed, but it is usually in the range of 90 to 250 ° C.

[0030]

The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following description. In addition, in each of Examples and Comparative Examples, the following materials were used as the resin raw material and the additive.

(A) Thermoplastic olefin elastomer: EPDM (propylene content 28% by weight, iodine value 15, Mooney viscosity (ML _{1 + 4} , 100 ° C.) 88) 55
Parts by weight and EVA (vinyl acetate content 28% by weight, melt index (190 ° C, 2.16 kg load) 20 g / 10)
Min) 30 parts by weight at room temperature using a Henschel mixer, followed by roll kneading at about 120 ° C. and pelletizing.

(B) Hydrogenated diene copolymer: Dynaron
1320P (trade name) (manufactured by Japan Synthetic Rubber Co., Ltd., bound styrene content 10%, melt flow rate (230 ° C, 2.16 kg)
Load) 3.5 g / 10 minutes, Shore A hardness 39, hydrogenation rate 99% or more. (C) Water-absorbent resin: Aqualic CS-6S (manufactured by Nippon Shokubai Chemical Co., Ltd .; polyacrylate type). (D) Inorganic filler: silica (manufactured by Hayashi Kasei Co., Ltd .; Micron White 5000A, average particle size 6 μm). (E) Softener: Mineral oil (Idemitsu Petrochemical Co., Ltd .; PW
-380 (trade name), paraffinic mineral oil). (F) Plasticizer: DIDP (diisodecyl phthalate).

(G) Organic peroxide type crosslinking agent: Perhexa 3M (manufactured by NOF CORPORATION; peroxyketal, 1 minute half-life temperature 149 ° C.). (H) Crosslinking aid: (1) Metal salt of α, β-unsaturated carboxylic acid: zinc diacrylate (ZA; manufactured by Kawaguchi Chemical Industry Co., Ltd.), zinc dimethacrylate (ZMA; manufactured by Kawaguchi Chemical Industry Co., Ltd.) . (2) Bismaleimide compound: N, N'-m-phenylene bismaleimide (PBM-R: manufactured by Kawaguchi Chemical Industry Co., Ltd.). (3) Polyfunctional vinyl monomer: divinylbenzene (DV
B).

Examples 1 to 7, Comparative Examples 1 to 4 After preliminarily kneading an olefinic thermoplastic elastomer consisting of 30 parts by weight of EVA and 55 parts by weight of EPDM and 10 parts by weight of a water absorbent resin at room temperature with a Henschel mixer. , Hydrogenated diene copolymer 15 parts by weight, inorganic filler 2 parts by weight, softener 10 parts by weight, plasticizer 30 parts by weight and first
Organic peroxide cross-linking agents and cross-linking aids (ZA, ZM shown in the table
A, PBM-R and DVB) were melt-kneaded at 140 ° C. using a Brabender mixer, pelletized and then formed into a sheet. The physical properties of the resulting water absorbent resin crosslinked sheet are
Shown in the table.

The methods for measuring the physical properties shown in Table 1 are as follows. (1) JIS A hardness: measured according to JIS K6301. (2) Tensile breaking strength: Measured according to JIS K6301 (23 ° C). (3) Tensile elongation at break: Measured according to JIS K6301. (4) Water absorption rate after 1 day and 7 days: A value obtained by dividing the weight of the resin crosslinked body after water absorption by the weight of the resin crosslinked body before water absorption. (5) Weight retention rate: A value obtained by once drying the swelled product, weighing it, and dividing the weight by the weight before swelling (the smaller this value is, the more gel is removed from the water absorbing agent).

As is clear from Table 1, the crosslinked water absorbent resin of the present invention has a good balance of physical properties.

[0037]

[Table 1]

[0038]

[Table 2]

[0039]

The water-absorbent resin crosslinked product according to the present invention is based on an olefinic thermoplastic elastomer, and has a specific amount of water-absorbent resin, an inorganic filler, a softening agent, a plasticizer, a crosslinking agent and a specific crosslinking auxiliary agent. Is a composition obtained by blending and cross-linking, and has good workability at low temperature due to excellent flexibility, etc., excellent water absorption rate and water absorption rate due to blending of hydrogenated diene copolymer, vulcanization step and ionization property. It has features such as excellent productivity and manufacturing that does not require a radiation irradiation step. Such a crosslinked body of the present invention is a waterproof seal between segments of tunnels and water and sewerage construction, communication cables, joint sealing materials for underground cables such as telephone lines, civil engineering such as seals for gaps in exterior wall panels of buildings, It can also be used as a waterproofing material for construction work, an anti-condensation material that also has an anti-seismic function, and a water retention material for agriculture and forestry and horticulture.

Claims (1)

[Claims] 1. (a) Polyethylene polymer 15-55
Wt% and ethylene-propylene-diene copolymer 85-
(B) Hydrogenated diene-based copolymer 1 with respect to 100 parts by weight of an olefin-based thermoplastic elastomer composed of 45% by weight
The component (a) + (b) 1 containing 0 to 100 parts by weight.
(C) 5 to 95 parts by weight of water-absorbent resin, (d) 1 to 25 parts by weight of inorganic filler, (e) 2 to 50 parts by weight of softening agent, and (f) plasticizer 2 to 00 parts by weight. 50 parts by weight,
(G) 0.05 to 5.0 parts by weight of an organic peroxide-based crosslinking agent,
(H) A resin composition containing a metal salt of an α, β-unsaturated carboxylic acid, a bismaleimide compound, and 0.1 to 10.0 parts by weight of one or more crosslinking aids selected from polyfunctional vinyl monomers. A crosslinked water-absorbent resin characterized by being crosslinked.