JP2001139795A - Rubber composition, crosslinking rubber composition and crosslinked product thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a rubber composition, a crosslinking rubber composition and a crosslinked product thereof having low surface frictional resistance and low volume resistivity, excellent in ozone resistance and mechanical properties, having water absorptivity and water swelling characteristics and having a property exhibiting low contact angle of water on the surface thereof. SOLUTION: This rubber composition comprises (A) 25-95 wt.% of polyether- based polymer containing 70-99 mol% of ethylene oxide unit, 1-30 mol% of other oxysilane monomer unit than the ethylene oxide and <=15 mol% of a crosslinking oxysilane monomer unit and having 20-200 Mooney viscosity and (B) 5-75 wt.% of an unsaturated rubber. The crosslinking rubber composition and the crosslinked product thereof comprise the rubber composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel rubber composition, a crosslinkable rubber composition and a crosslinked product thereof.

[0002]

2. Description of the Related Art JP-A-9-146345 discloses that a rubber composition containing an epihalohydrin copolymer rubber, an unsaturated rubber and a liquid unsaturated rubber is suitable as a material for a charging roll. As an effect, the rubber composition as a roll material has a low surface friction coefficient and a low hardness. But,
In order to reduce the surface frictional resistance, an ultraviolet irradiation treatment was necessary, and those not treated could not be sufficiently reduced.

JP-A-10-60179 discloses that a self-lubricating rubber composition containing a rubber component, a cross-linking agent and a polyethylene glycol type surfactant is used for an anti-vibration rubber. It is mentioned that the friction resistance is low. However, although low-molecular-weight polyether blooms to reduce frictional resistance, the progress of abrasion removes the polyether blooming on the surface, and thus has a problem in sustainability. The polyether used has a degree of polymerization of oxyethylene of about 5 to 20, a molecular weight of 900 or less, and a Mooney viscosity of less than a measurable range. Further, the rubber composition does not have a cross-linking site, and the strength physical properties of a cross-linked product of a rubber composition added in a large amount may be reduced.

[0004] In the republished WO 97-39055,
It is disclosed that a rubber composition containing 0.1 to 25 parts by weight of a polyether-based polymer is used for a tire based on 100 parts by weight of a diene-based rubber.
It is mentioned that it is excellent in tensile strength and workability and can also impart antistatic performance. However, it is not described that the frictional resistance is small, and the fact is that the frictional resistance is not reduced unless a large amount of a polyether polymer is blended.

JP-A-8-292640 discloses that 28 to 79 mol% of alkylene oxide, 28 to 70 mol% of epihalohydrin, and ethylenically unsaturated epoxide 2
Polymer (A) obtained by copolymerizing 〜15 mol%
100 parts by weight of a rubber component containing 95% by weight and 5 to 75% by weight of an unsaturated rubber (B) and 0.1 to 5 parts by weight of a crosslinking agent (C) composed of a sulfur-based crosslinking agent or peroxide. A rubber composition for a rubber roll is disclosed, and its effect is to obtain a roll having no photoconductor contamination, low electrical resistance, low environmental dependency of resistance, and low hardness. However, there is no disclosure regarding frictional resistance.

[0006] Japanese Patent Application Laid-Open No. Hei 4-3726251, Japanese Patent Application Laid-open No. Hei 8
No. 20715 discloses a crosslinked product of a single rubber such as an ethylene oxide-propylene oxide-allyl glycidyl ether terpolymer, an ethylene oxide-epichlorohydrin-allyl glycidyl ether terpolymer and the like. Although it is disclosed as a conductive rubber, it does not disclose frictional resistance or electric resistance. In addition, crosslinked products of these single rubbers have low strength physical properties at the time of water swelling,
It was also difficult to control the degree of water swelling.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a low surface frictional resistance and low volume specific resistance, excellent ozone resistance and mechanical properties, water absorption and water swelling, and water on the surface. It is an object of the present invention to provide a novel rubber composition, a crosslinkable rubber composition and a crosslinked product thereof having a characteristic of a low contact angle.

[0008]

A first object of the present invention is to provide a crosslinkable oxirane monomer containing 70 to 99 mol% of ethylene oxide units and 1 to 30 mol% of oxirane monomer units other than ethylene oxide. 25 to 95% by weight of a polyether polymer (A) having a unit of 15 mol% or less, Mooney viscosity of 20 to 200, and an unsaturated rubber (B)
5 to 75% by weight.

A second aspect of the present invention is characterized in that the rubber composition contains 100 parts by weight of a rubber component mainly composed of the rubber composition according to claim 1 and 0.1 to 10 parts by weight of a crosslinking agent (C). The present invention relates to a crosslinkable rubber composition.

[0010] A third aspect of the present invention is that a rubber component containing the rubber composition according to claim 1 as a main component is 100 parts by weight, and a crosslinking agent (C).
0.1 to 10 parts by weight and inorganic oxide (D) 10 to 20
0 parts by weight of a crosslinkable rubber composition.

A fourth aspect of the present invention relates to a crosslinked product obtained by crosslinking the rubber composition according to claim 2 or 3.

The polyether polymer (A) used in the present invention is a ring-opened polymer of an oxirane monomer, and 70 to 99 mol%, preferably 75 to 97 mol% of ethylene oxide units in all monomers. %, Particularly preferably 80 to 9
5 mol% and 1 to 30 mol% of oxirane monomer units other than ethylene oxide, preferably 3 to 25 mol%,
Particularly preferred is a copolymer containing 5 to 20 mol%.

The oxirane monomer other than ethylene oxide is a compound in which at least one hydrogen of ethylene oxide is substituted. The polyether polymer (A) of the present invention contains a crosslinkable oxirane monomer unit. In the present invention, a crosslinkable oxirane monomer is used for crosslinking a polyether-based polymer (A) obtained by copolymerizing the monomer.
An oxirane monomer that can form a crosslinked structure by reacting with a crosslinking agent. The polyether-based polymer (A) containing a crosslinkable oxirane monomer unit can improve the strength properties by crosslinking.

In the polyether polymer (A), the crosslinkable oxirane monomer unit is 15 mol% or less, preferably 1 to 13 mol%, more preferably 2 to 1 mol% in all monomer units.
1 mol%. If the amount of the crosslinkable oxirane monomer unit is too small, the polyether polymer (A) cannot be crosslinked, and the strength physical properties of the obtained crosslinked product may be reduced. If the number of the crosslinkable oxirane monomer units is too large, the hardness of the crosslinked product becomes too high, and the elongation tends to decrease.

Examples of the crosslinkable oxirane monomer include epihalohydrins such as epichlorohydrin, epibromohydrin, epiiodohydrin and epifluorohydrin, and halogen-substituted such as p-chlorostyrene oxide and dibromophenylglycidyl ether. Oxirane compounds;
Alkenyl glycidyl ethers such as allyl glycidyl ether and butenyl glycidyl ether; alkenyl epoxides such as 3,4-epoxy-1-butene, 1,2-epoxy-5-hexene and 1,2-epoxy-9-decene; Glycidyl esters of unsaturated carboxylic acids such as glycidyl acrylate and glycidyl methacrylate; and crosslinkable unsaturated epoxides.
Two or more crosslinkable oxirane monomers may be used in combination.

Oxirane monomers other than ethylene oxide which are non-crosslinkable include, for example, propylene oxide, 1,2-epoxybutane, 1,2-epoxyisobutane, 2,3-epoxybutane, , 2-
Epoxyhexane, 1,2-epoxyoctane, 1,2
-Epoxydecane, 1,2-epoxytetradecane,
Alkylene oxides such as 1,2-epoxyhexadecane and 1,2-epoxyoctadecane; cycloaliphatic epoxides such as cyclohexene oxide and vinylcyclohexene oxide; methyl glycidyl ether;
Glycidyl ethers such as ethyl glycidyl ether and butyl glycidyl ether; and styrene oxide and phenyl glycidyl ether.

Further, a diepoxy compound for introducing a branched structure into a polymer such as butadiene dioxide, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, or vinylcyclohexenedioxide may be copolymerized.

If the amount of the ethylene oxide unit is too large and the amount of the other oxirane monomer units is too small, crystallization of the oxyethylene chain is caused, the effect of reducing the electric resistance of the composition is impaired, and the hardness of the composition increases. Impairs rubber elasticity. If the ethylene oxide unit amount is too small, the effect of reducing the surface frictional resistance and the effect of reducing the electrical resistance of the composition will be impaired. If the amount of ethylene oxide units is too small and the amount of other oxirane monomer units is too large, the properties of the polyether-based polymer (A) become rubbery. In the production, the polymer is likely to adhere to the polymerization reactor in the polymerization step, or a problem such as crumb cohesion occurs in the step of separating the polymer from the solvent,
Problems such as sticking of the polymer particles during storage occur. As the content of the oxirane monomer unit having a large molecular weight increases, the problem of clam adhesion tends to occur, and the content of the oxirane compound unit having a molecular weight of 90 or more is preferably set to 15 mol% or less.

The polyether polymer (A) contains 70 to 99 mol% of ethylene oxide units and 1 to 30 mol% of oxirane monomer units other than ethylene oxide, and contains 15 to 15 crosslinkable oxirane monomer units. Mol% or less, preferably 75 to 97 mol% of ethylene oxide units and 0 to propylene oxide units.
To 24 mol%, and 1 to 13 mol% of a crosslinkable oxirane monomer unit, and particularly preferably, 80 to 95 mol% of an ethylene oxide unit, 0 to 18 mol% of a propylene oxide unit, and It is a copolymer comprising 2 to 11 mol% of a saturated epoxide unit.

The Mooney viscosity of the polyether polymer (A) is from 20 to 200, preferably from 30 to 170, more preferably from 40 to 150. If the Mooney viscosity is too high, the moldability is poor, especially the swell is large, and the dimensional stability is reduced. If the Mooney viscosity is too low, the mechanical strength of the crosslinked product will decrease.

The polyether-based polymer (A) may be either a block copolymer or a random copolymer. However, the random copolymer has a lower electric resistance due to a decrease in the crystallinity of polyethylene oxide. Is preferred.

The polyether copolymer (A) can be obtained by subjecting a predetermined oxirane monomer to ring-opening polymerization by a solution polymerization method or a solvent slurry polymerization method. The polymerization catalyst is not particularly limited as long as it is a general polyether polymerization catalyst. For example, a catalyst in which water and acetylacetone are reacted with organoaluminum (Japanese Patent Publication No.
No. 5,157,797), a catalyst obtained by reacting triisobutylaluminum with phosphoric acid and triethylamine (Japanese Patent Publication No. 46-27534), and a reaction of triisobutylaluminum with an organic acid salt of diazabiacycloundecene and phosphoric acid. Catalysts (JP-B-56-51171), catalysts comprising a partially hydrolyzed aluminum alkoxide and an organic zinc compound (JP-B-43-2945),
A catalyst comprising an organic zinc compound and a polyhydric alcohol (Japanese Patent Publication No. 45-7751), a catalyst comprising a dialkyl zinc and water (Japanese Patent Publication No. 36-3394) and the like can be mentioned.

The polymerization method is not particularly limited, and a solution polymerization method, a solvent slurry polymerization method, or the like is used. As the polymerization solvent, aromatic hydrocarbons such as benzene and toluene; n
Linear saturated hydrocarbons such as -pentane and n-hexane; alicyclic hydrocarbons such as cyclopentane and cyclohexane; Preferably, polymerization is performed by a solvent slurry polymerization method using a poor solvent. In this case, since the polyether polymer (A) has water solubility, the step of separating the solvent and the polymer can be performed efficiently. For example, n-pentane, n-hexane, cyclopentane, cyclohexane, and the like do not dissolve the ring-opening polymer of ethylene oxide, but dissolve the ring-opening polymer of propylene oxide. Since the characteristics of the obtained polyether polymer (A) differ depending on the amount ratio, the poor solvent is selected according to the desired characteristics of the polyether polymer (A). In the solvent slurry polymerization method, the polymerization is performed by mixing a catalyst component and a small amount of ethylene oxide and propylene oxide in a poor solvent, and
The reaction is carried out at a temperature of 30 ° C., preferably 30 to 50 ° C. for 10 to 30 minutes to form catalyst particles having low adhesion to the reactor wall and the like, and then a monomer is added and polymerized.

The polymerization reaction is carried out at 0 to 100 ° C., preferably at 3 to 100 ° C.
It can be carried out at 0 to 70 ° C. by any method such as a batch system, a semi-batch system, and a continuous system.

The unsaturated rubber (B) is a rubber other than the polymer of the oxirane monomer, is a rubber capable of crosslinking sulfur having an ethylenic carbon-carbon unsaturated bond in the molecule, and has an iodine value of 3 to 3. 500 is preferable, and 5-350 is more preferable. The unsaturated rubber (B) is not particularly limited and includes, for example, butadiene rubber, styrene-butadiene rubber, isoprene rubber, natural rubber, acrylonitrile-
Examples include butadiene rubber, acrylonitrile-butadiene-isoprene rubber, ethylene-propylene-diene rubber, chloroprene rubber and partially hydrogenated products of these rubbers. These unsaturated rubbers can be used alone or in combination of two or more.

Particularly preferred unsaturated rubbers (B) in the present invention include acrylonitrile-butadiene rubber, acrylonitrile-butadiene-isoprene rubber, partially hydrogenated products thereof and chloroprene from the viewpoint of compatibility with the polyether polymer. Rubber is preferred, from the viewpoint of strength properties, hydrogenated acrylonitrile-butadiene rubber, natural rubber, isoprene rubber is preferred, from the viewpoint of electrical properties acrylonitrile-butadiene rubber, acrylonitrile-butadiene-isoprene rubber and these hydrogenated products Is preferred, and may be selected depending on the intended use of the rubber composition. In the acrylonitrile-butadiene rubber, the acrylonitrile unit is preferably 15 to 50% by weight, more preferably 20 to 4% by weight.
0% by weight. Preferred hydrogenated acrylonitrile-butadiene rubbers are those obtained by hydrogenating preferred acrylonitrile-butadiene rubbers to an iodine value of 50 or less, preferably 30 or less. If the acrylonitrile unit amount is too small, the composition is inferior in flexural fatigue and electrical resistance is increased, which is not preferable. If the amount is too large, the composition becomes hard and rubber elasticity is impaired.

The rubber composition of the present invention comprises 25 to 95% by weight of a polyether polymer (A) and 5 to 7% of an unsaturated rubber (B).
Contains 5% by weight. The amount of the unsaturated rubber (B) is preferably in the range of 10 to 70% by weight with respect to 30 to 90% by weight of the polyether-based polymer (A), and particularly preferably 35 to 85% by weight of the polyether-based polymer (A). The unsaturated rubber (B) is in the range of 15 to 65% by weight with respect to% by weight. If the amount of the polyether-based polymer (A) is too small and the amount of the unsaturated rubber (B) is too large, the effect of reducing the surface frictional resistance of the crosslinked product is not sufficient, and the electric resistance increases. If the amount of the polyether-based polymer (A) is too large and the amount of the unsaturated rubber (B) is too small, the crosslinked product tends to absorb moisture, and the dimensional stability and mechanical strength of the molded product are poor. In some cases, there is a problem that the electric resistance greatly fluctuates due to the environment such as temperature and humidity.

The rubber component of the present invention is a rubber containing the rubber composition of claim 1 as a main component, and the rubber which can be used in combination with the rubber composition of claim 1 does not lose the object and effect of the present invention. Within the range, rubbers, thermoplastic elastomers and / or resin components other than the above (A) and (B) can be blended. The electric resistance, the surface friction resistance and the water swelling property of the crosslinked product of the present invention can be adjusted by adjusting the blending amount.

In the rubber composition of the present invention, a crosslinked rubber containing 25 to 90% by weight of the polyether polymer (A) and 10 to 75% by weight of the unsaturated rubber (B) is water-swellable. Excellent as rubber. When used as a material for water-swellable rubber, polyether-based polymer (A) 30 to 8
A rubber composition containing 5% by weight and 15 to 70% by weight of the unsaturated rubber (B) is preferable, and the polyether polymer (A)
35 to 80% by weight and unsaturated rubber (B) 20 to 65% by weight
Is more preferable. When used as a rubber composition for water-swelled rubber, if the amount of the polyether-based polymer (A) is too small and the amount of the unsaturated rubber (B) is too large, the volume change rate of the crosslinked product during water swelling Is insufficient, and the water contact angle becomes high. On the other hand, when the amount of the polyether polymer (A) is too large and the amount of the unsaturated rubber (B) is too small, there is a problem that the strength properties of the crosslinked product upon swelling in water are extremely reduced.

The inorganic oxide (D), which is preferable as a compounding agent in the composition of the present invention, includes oxides of silicon, aluminum, calcium, zinc, titanium, magnesium and the like. You may use together. Silica, which is an oxide of silicon, is preferred because it has a particularly high affinity for the polyether polymer and the mechanical strength of the composition is increased. Among silicas, silica having a BET adsorption surface area of 100 to 200 m ² / g is preferred because a composition having excellent processability of the composition and strength properties of a crosslinked product can be obtained. Further, silica having a pH value of 8 to 12 is preferable, and silica having a pH value of 9 to 11 is more preferable. Silica p
If H is too high, the crosslinking rate is too high during crosslinking of the rubber composition of the present invention, and scorch tends to occur. If it is too low, the electric resistance of the crosslinked product of the present invention increases.

The amount of the inorganic oxide (D) used is the same as that of the rubber component 1
10 to 200 parts by weight, more preferably 15 to 150 parts by weight, particularly preferably 2 to 100 parts by weight.
0 to 100 parts by weight. If the amount of the inorganic oxide (D) is too small, the strength properties of the crosslinked product are low, and the extrudability tends to be poor due to the large swell. If the amount of the inorganic oxide (D) is too large, the hardness of the crosslinked product becomes too high,
Rubber elasticity may be impaired.

The crosslinking agent (C) is not particularly limited, and examples thereof include a sulfur crosslinking agent, an organic peroxide crosslinking agent, a mercaptotriazine crosslinking agent, and a thiourea crosslinking agent. Examples of the sulfur crosslinking agent include, in addition to sulfur, sulfur-containing compounds such as morpholine disulfide and alkylphenol disulfide. Organic peroxide crosslinking agents include ketone peroxides such as cyclohexanone peroxide and methyl acetoacetate peroxide; peroxyesters such as tert-butyl peroxyisobutyrate and tert-butyl peroxybenzoate; benzoyl peroxide And diacyl peroxides such as lauroyl peroxide; alkyl peroxides such as dicumyl peroxide, di-tert-butyl peroxide, and 1,3-bis (tert-butylperoxyisopropyl) benzene; and the like. Examples of the thiourea-based crosslinking agent include thiourea, dibutylthiourea, and triethylthiourea.
As mercaptotriazine-based crosslinking agents, 2,4,6-
Trimercapto-s-triazine, 2-methyl-4,6
-Dimercapto-s-triazine, 2-ethylamino-
4,6-dimercapto-s-triazine and the like can be mentioned. When an oxirane monomer having a halogen is used as an oxirane monomer having a reactive functional group and crosslinking is performed using a halogen as a crosslinking point, a mercaptotriazine-based crosslinking agent, a thiourea-based crosslinking agent, or the like is used as a crosslinking agent. When a crosslinked product having a low electric resistance is obtained, it is preferable to use a sulfur crosslinking agent as the crosslinking agent. When a crosslinked product having a small compression set is obtained, it is preferable to use an organic peroxide crosslinking agent as the crosslinking agent. Rubber component (A) 1
The mixing amount of the crosslinking agent is 0.1 to 10 parts by weight, preferably 0.2 to 7 parts by weight, more preferably 0.1 to 100 parts by weight.
It is 3 to 5 parts by weight.

If necessary, a crosslinking accelerator or a crosslinking aid may be added. The crosslinking accelerator and the crosslinking assistant are not particularly limited, and can be appropriately selected and used according to the crosslinking agent. Crosslinking agents other than organic peroxides, such as sulfur crosslinking agents, mercaptotriazine-based crosslinking agents, and thiourea-based crosslinking agents, when used as crosslinking accelerators, include thiuram-based accelerators, thiazole-based accelerators, and sulfenes. Amide accelerators and the like. Examples of the thiuram-based accelerator include tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide and the like. Examples of the thiazole accelerator include 2-mercaptobenzothiazole and dibenzothiazyl disulfide. Examples of the sulfenamide-based accelerator include N-cyclohexyl-2-benzothiazylsulfenamide, N-oxydiethylene-2-benzothiazylsulfenamide and the like. These crosslinking accelerators may be used in combination of two or more. The upper limit of the amount of the crosslinking accelerator used is 100 parts by weight of the rubber component.
Parts by weight, preferably 12 parts by weight, more preferably 10 parts by weight. As crosslinking aids, metal oxides such as zinc oxide and magnesium oxide; metal hydroxides such as calcium hydroxide; metal carbonates such as zinc carbonate and basic zinc carbonate; fatty acids such as stearic acid and oleic acid; stearin Fatty acid metal salts such as zinc acid and magnesium stearate are exemplified. When an organic peroxide is used, a compound having at least two crosslinkable unsaturated bonds in the molecule can be used as a crosslinking assistant. Specific examples include ethylene dimethacrylate, diallyl phthalate, N, Nm-phenylenedimaleimide, triallyl isocyanurate, trimethylolpropane trimethacrylate, and liquid vinyl polybutadiene. Two or more of these crosslinking assistants can be used in combination. The upper limit of the amount of the crosslinking aid used is 20 parts by weight,
It is more preferably 15 parts by weight, more preferably 10 parts by weight.

In the present invention, an alkali metal salt or an alkaline earth metal salt may be contained in order to adjust the electric resistance of the composition to a desired level. The polyether-based polymer (A) is also an ion-conductive polymer, and has a property that when an alkali metal ion or an alkaline earth metal ion is introduced, the electric resistance is greatly reduced.

The alkali metal salt or alkaline earth metal salt is not particularly limited as long as it is soluble in the polyether polymer (A) of the present invention or a crosslinked product thereof. For example, alkyl sulfonate ion, alkylbenzene sulfonate ion, chloride ion, bromine ion, iodine ion, perchlorate ion, thiocyanate ion, tetrafluoroborate ion, nitrate ion, acetate ion, AsF
₆ ⁻ , PF ₆ ⁻ , CF ₃ SO ₃ ⁻ , N (CF ₃ SO ₂ )
₂ ^-, _CF 3 CO ₂ ^- from the, selected from the group consisting of such anions, Li, Na, K, Rb , Cs, Mg, and an alkali metal or alkaline earth metal cations such as Ca and Ba Salt. These alkali metal salts and / or alkaline earth metal salts may be used in combination of two or more.

The amount of the alkali metal salt or alkaline earth metal salt is 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, per 100 parts by weight of the polyether polymer.
More preferably, it is in the range of 0.5 to 3 parts by weight. If the amount of the alkali metal salt or the alkaline earth metal salt is too small, the change in the electrical resistance of the composition is insufficient. If the amount is too large, the composition cannot be sufficiently dissolved in the polyether polymer (A). It blooms and the mechanical strength of the crosslinked product decreases.

In the rubber composition of the present invention, in order to reduce the electric resistance, a compounding agent having a function as an antistatic agent such as a surfactant such as a nonionic surfactant is mixed with a polyether polymer ( You may use together with A). When a surfactant is added, the amount is preferably 5 parts by weight or less, particularly preferably 4 parts by weight or less, based on 100 parts by weight of the rubber component. If the added amount of the surfactant is large, the strength physical properties tend to be reduced, and problems such as bleeding out on the surface of the composition may occur.

In the present invention, in addition to the above compounding agents, other reinforcing agents, fillers, softeners, plasticizers, antistatic agents,
Ordinary compounding agents such as surfactants, flame retardants, antioxidants, stabilizers, foaming agents, silane coupling agents and activators can also be added as appropriate.

The composition of the present invention can be prepared by a desired method,
Can be kneaded. For example, kneading molding may be performed by kneading one or more kneading molding machines such as a kneader, a banbury, an open roll, a calender roll, and an extruder, or after dissolving in a solvent and mixing, removing the solvent. May be formed.

Regarding the crosslinking method, molding and crosslinking may be performed simultaneously, or crosslinking may be performed after molding. The rubber composition of the present invention can be crosslinked by heating, and the lower limit of the heating temperature at that time is preferably 130 ° C.
The temperature is more preferably 140 ° C., and the upper limit is preferably 2 ° C.
00 ° C. If the temperature is too low, a long crosslinking time may be required or the crosslinking density may be low. If the temperature is too high, crosslinking may proceed in a short time, and molding failure may occur. The crosslinking time varies depending on the crosslinking method, crosslinking temperature, shape and the like, but is preferably in the range of 1 minute or more and 5 hours or less from the viewpoint of crosslinking density and production efficiency. As a heating method, a method used for rubber crosslinking such as press heating, steam heating, oven heating, and hot air heating may be appropriately selected.

[0041]

EXAMPLES The present invention will be described below with reference to Production Examples, Examples and Comparative Examples, but the present invention is not limited thereto. (1) Mooney viscosity (ML _{1 + 4} , 100 ° C)
It was measured according to SK6300. (2) The tensile test conformed to JIS K6251. (3) The volume resistivity was measured according to JIS K6911. (4) The dynamic friction coefficient μ is in accordance with ASTM D1894,
Using a SUS ball indenter, load 100g, speed 10
Under the condition of 0 mm / min, Shinto Kagaku's surface measuring device HEID
It was measured using ON-14D. (5) The rebound resilience was measured according to JIS K6255. (6) The hardness was measured according to JIS K6253. (7) The ozone deterioration test was measured according to JIS K6259. (8) Changes in weight and volume due to water swelling are determined according to JIS.
It was measured according to K6258. (9) The ozone deterioration test was evaluated according to JIS K6259.

Production Example 1 (Polyether-based polymer No. 1)
(Preparation of Catalyst Solution) An autoclave with a stirrer having an internal volume of 3 liters was dried and purged with nitrogen, and 158.7 g of triisobutylaluminum, 1170 g of toluene, and 296.4 g of diethyl ether were charged. The internal temperature was set at 30 ° C., and 23.5 g of orthophosphoric acid was gradually added with stirring. To this, 12.1 g of triethylamine was added, and
An aging reaction was performed at 2 ° C. for 2 hours to obtain a catalyst solution.

A 5-liter autoclave with a stirrer was dried and purged with nitrogen, and 2100 g of n-hexane and 73.1 g of the catalyst solution prepared above were charged. The internal temperature was set to 30 ° C., and 4 g of ethylene oxide was added to the mixture while stirring to cause a reaction.
8.5 g of a mixed monomer of propylene oxide = 50/50% by weight was added and reacted to form a seed.

(Preparation of Polymer) The internal temperature of the catalyst-dispersed solution containing the seed subjected to the above treatment was set at 60 ° C.
A mixed solution consisting of 347 g (90.6 mol%) of ethylene oxide, 16.4 g (3.3 mol%) of propylene oxide, 59.8 g (6.1 mol%) of allyl glycidyl ether and 300 g of normal hexane was taken over 5 hours. Added continuously. After completion of the addition, the reaction was performed for 2 hours.
The polymerization reaction rate was 98%. The obtained polymer was in a clean slurry state, and the inner wall of the autoclave and the stirring blade were very clean. 42.4 g of a 5% toluene solution of 4,4'-thiobis (6-tert-butylcresol) as an antioxidant was added to the obtained slurry and stirred. The powdery polymer was filtered through a wire net and dried in vacuum at 40 ° C. A clean powdery polymer sample was obtained.

The polyether polymer No. The composition (content of each monomer unit) of No. 1 was 90.0 mol% of ethylene oxide units, 4.0 mol% of propylene oxide units, and 6.0 mol% of allyl glycidyl ether units. The Mooney viscosity (ML _{1 + 4} , 100 ° C.) of this polymer was 105.2.

Production Example 2 (Polyether polymer No. 2
In the polymer preparation step, the monomers to be added were ethylene oxide 96.7 g (38.3 mol%), epichlorohydrin 306.5 g (58.6 mol%), and allyl glycidyl ether 20.1 g (3.1 mol%), except that the copolymerization was carried out in the same manner as in Production Example 1.

The polyether polymer No. The composition of No. 2 (bonding unit of each monomer) was 39.8 mol% of ethylene oxide, 1.2 mol% of propylene oxide, 56.0 mol% of epichlorohydrin, and 3.0 mol% of allyl glycidyl ether. Was. Also,
Mooney viscosity of this polymer (ML _{1 + 4} , 100 ° C)
Was 80.1. In this case, the polymer sample after drying was obtained as a rubbery mass and a lump, and adhesion of the polymer to the inner wall of the autoclave and the stirrer was observed.

Production Example 3 (Polyether polymer No. 3
Production of Polymer) In the polymer preparation step, 339 g (90.2 mol%) of ethylene oxide, 40.7 g (5.2 mol%) of epichlorohydrin, 43.6 g (4 g) of allyl glycidyl ether were added as monomers to be added. Copolymerization was carried out in the same manner as in Production Example 1 except that the composition was changed to 0.5 mol%).

The polyether polymer No. The composition of No. 3 (bonding unit of each monomer) was 89.7% by mole of ethylene oxide, 0.8% by mole of propylene oxide, 5.1% by mole of epichlorohydrin, and 4.4% by mole of allyl glycidyl ether. Was. The Mooney viscosity (ML _{1 + 4} , 100 ° C.) of this polymer is
85.2. In this case, the polymer sample after drying was in the same powder form as in Production Example 1, and no adhesion of the polymer to the inner wall of the autoclave and the stirrer was observed.

Production Example 4 (Polyether polymer No. 4
In the preparation process of the polymer, the monomers to be added were ethylene oxide 246.9 g (75.1 mol%), epichlorohydrin 141.1 g (20.7 mol%), and allyl glycidyl ether 35.3 g (4.2 mol%), except that the copolymerization was carried out in the same manner as in Production Example 1.

The polyether polymer No. The composition of No. 4 (bonding unit of each monomer) was 75.0 mol% of ethylene oxide, 0.7 mol% of propylene oxide, 20.2 mol% of epichlorohydrin, and 4.1 mol% of allyl glycidyl ether. Was. Also,
Mooney viscosity of this polymer (ML _{1 + 4} , 100 ° C)
Was 78.5. In this case, the polymer sample after drying was a rubber-like mass similar to that of Production Example 2, and adhesion of the polymer to the inner wall of the autoclave and the stirrer was observed.

Examples 1 to 6 and Comparative Examples 1 to 9 As the raw rubber, the polyether polymer No. obtained in Production Example 1 was used. 1, the polyether polymer No. 1 obtained in Production Example 2.
2, the polyether polymer No. obtained in Production Example 3 3, the polyether polymer No. 3 obtained in Production Example 4. 4, commercially available polyether polymer No. 5 (PEO-, manufactured by Sumitomo Seika)
8), acrylonitrile-butadiene rubber, and natural rubber were used. These formulations are shown in Tables 2-5. Based on this compounding recipe, in a Banbury mixer having a capacity of 250 ml, the whole amount of the raw rubber and the whole amount of silica were mixed at 80 ° C. for 2 minutes, and the remaining compounding agents except for sulfur and the vulcanization accelerator were added. For 2 minutes. Next, the obtained mixture, sulfur and a vulcanization accelerator were added to an open roll at 50 ° C. and kneaded, followed by press vulcanization at 150 ° C. for 30 minutes to prepare a test piece, and each physical property was measured. Table 2 shows the results.
5 is shown.

[0053]

[Table 1]

[0054]

[Table 2]

[0055]

[Table 3]

[0056]

[Table 4]

[0057]

[Table 5]

Further, with respect to the crosslinked products of the compositions of Example 1, Example 2, Comparative Example 1 and Comparative Example 9, the temperature and humidity were changed and the volume resistivity was examined. Table 6 shows the results.

[Table 6]

The following can be understood from the above results. From Comparative Example 1, the crosslinked product of the composition containing only acrylonitrile butadiene rubber as the rubber has a tensile strength of 100
% Tensile stress, large volume specific resistance, large dynamic friction coefficient, poor ozone degradation resistance, and large changes in volume specific resistance due to environmental changes. From Comparative Example 2, the crosslinked product of the composition using a homopolymer of ethylene oxide as the polyether polymer is inferior in tensile strength, elongation and 100% tensile stress, hard, and has a large volume resistivity. From Comparative Examples 3 and 7, the crosslinked product of a composition using a copolymer having a small amount of ethylene oxide units and a high content of a crosslinkable oxirane monomer as a polyether-based polymer has a volume resistivity value, The coefficient of kinetic friction is large, the resistance to ozone deterioration is poor, and the water swelling property is poor. From Comparative Examples 4 and 8, the crosslinked product of the composition having a small content of the polyether polymer has a large volume resistivity and a high dynamic friction coefficient, is inferior in ozone deterioration resistance, and further inferior in water swelling. From Comparative Example 5, although the ethylene oxide unit amount is sufficient, the crosslinked product of the composition using the polyether polymer having a large content of the crosslinkable oxirane monomer is inferior in tensile strength and elongation and hard. From Comparative Example 6, the crosslinked product of the composition containing only natural rubber as the rubber has a very large volume specific resistance and does not easily swell with water. From Comparative Example 9, the crosslinked product of the composition containing only the polyether-based polymer as the rubber has a tensile strength of
It is inferior in elongation and 100% tensile stress, the volume specific resistance value largely fluctuates due to environmental changes, and when swelled with water, the crosslinked product has a much lower tensile strength, elongation and 100% tensile stress.

[0060]

(1) From the results of Tables 2 to 6, the rubber compositions of the present invention (Examples 1 to 6) have low surface friction resistance, low electric resistance, and stable electric resistance to the environment. It can be seen that the rubber has excellent physical properties as rubber and also has good ozone resistance. Taking advantage of these characteristics, for example, in various office equipment such as copiers and laser beam printers, it can be used for rubber parts such as belts, drums, blades, and rollers that require low electrical resistance as a mechanism for printing paper and the like. In the semiconductor industry,
It can be used as a material for rubber parts requiring low electric resistance, such as C trays, IC conveyor belts, IC packaging films and sheets. Further, it can be used as a material for a conveyor belt or a roll of a vending machine for conveying bills, cards, tickets, etc., public telephones, ATMs, etc., because of its stable moderate coefficient of friction, excellent strength characteristics, and ozone resistance.
Further, when used as a spinning roll for a blend spinning, the yarn slips well and the winding of the yarn due to electrification can be prevented, which is preferable. The semiconductive rubber roll material for OA equipment is a rubber roll having a semiconductive rubber layer around a shaft, and the rubber layer may have a single layer structure or a multilayer structure. When the rubber layer has a multilayer structure, the composition of the present invention is an outer layer, an inner layer,
Alternatively, it can be used as an intermediate layer. It is preferably used as an outer layer in order to make use of the property of stable surface friction resistance. When used for the roll surface layer, a protective layer may be provided on the surface layer as long as the properties of the semiconductive rubber layer are not impaired.
Further, a foam obtained by foaming the composition of the present invention can be used as a semiconductive rubber layer. (2) The rubber composition of the present invention has water absorbing properties, water swelling properties,
It also has the property of low water contact angle on the surface, making use of these properties to make use of sheet materials such as water swelling waterproof sheet, fog-proof sheet, drip-proof sheet, fume pipe joint, manhole joint, bottle packing. It can be suitably used as a material for packing such as a water-stop plug, a water-stop plate of a concrete joint surface, a segment seal for a shield method, and a water-absorbing roll material such as a water supply roll for offset printing.

 ──────────────────────────────────────────────────続 き Continuing on the front page F term (reference) 4J002 AC01X AC02X AC03X AC06X AC07X AC08X AC09X BB15X CH02W DA046 DE077 DE087 DE107 DE137 DE147 DJ017 EK036 EK046 EK056 EK066 EV036 EV126 EV346 FD017 FD110 FD146 FD150 GJ02 GM

Claims (4)

[Claims] 1. A Mooney viscosity which contains 70 to 99 mol% of ethylene oxide units and 1 to 30 mol% of oxirane monomer units other than ethylene oxide, and has a crosslinkable oxirane monomer unit of 15 mol% or less. 20-2
A rubber composition comprising 25 to 95% by weight of a polyether polymer (A) and 5 to 75% by weight of an unsaturated rubber (B). 2. 100 parts by weight of a rubber component comprising the rubber composition according to claim 1 as a main component and 0.1 to 1 of a crosslinking agent (C).
A crosslinkable rubber composition comprising 0 parts by weight. 3. 100 parts by weight of a rubber component comprising the rubber composition according to claim 1 as a main component, 0.1 to 10 parts by weight of a crosslinking agent (C) and 10 to 200 parts by weight of an inorganic oxide (D). A crosslinkable rubber composition characterized by containing: 4. A crosslinked product obtained by crosslinking the rubber composition according to claim 2 or 3.