JPH0649426A - Epoxy adhesive, bonding method and membrane module - Google Patents

Abstract

PURPOSE:To enhance adhesion to a porous adherend such as polyolefin without carrying out surface treatment and stably use a membrane module over a long period even at high temperature under high pressure. CONSTITUTION:A porous adherend having low energy surface such as an olefin based polymer is bonded with an epoxy based adhesive containing a nonaromatic epoxy compound (an aliphatic, alicyclic or alicyclic-aliphatic fatty acid epoxy resin compound). The epoxy compound includes a glycidylamine type or a glycidyl ether type epoxy compound. The adhesive contains a curing agent such as an aromatic amine and a curing accelerator. The adhered contains a porous membrane, etc. A membrane module obtained by bonding and sealing the end part of a porous hollow membrane with the epoxy adhesive is excellent in sealing property at high temperature under high pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy adhesive having adhesiveness to an adherend composed mainly of an olefin polymer, a bonding method using this composition, and a membrane module.

[0002]

2. Description of the Related Art In the reverse osmosis method, the ultrafiltration method, etc.,
A membrane separation module in which a separation membrane is sealed at the end of a case, particularly a hollow fiber type membrane separation module, is widely used. on the other hand,
The separation operation by the hollow fiber type membrane separation module is performed by supplying a fluid from the primary side to the hollow fiber membrane under high pressure, and selectively permeating a predetermined component in the fluid to the secondary side through the hollow fiber membrane, and a non-permeable component. Is concentrated. Also, in order to increase the permeation efficiency, it is advantageous to supply the heating fluid. Since pressure history and heat history act on such a hollow fiber type membrane separation module, especially on the sealing portion, the module is required to have a high sealing property between the hollow fiber bundle and the case.

On the other hand, polyolefins and fluorine-containing polymers usually have small surface energy and do not have polar groups involved in adhesion, and therefore adhesion of adherends containing these polymers is generally difficult. Therefore, a hot melt type adhesive is used for bonding these adherends.

However, the hot-melt type adhesive generally has a high viscosity and a low heat resistance, so that it is poor in versatility. In particular,
It is not suitable for casting an adhesive into a narrow space and adhering it in a narrow space like a membrane separation module.

Also known is a method of subjecting the surface of an adherend to physical or chemical treatment in order to enhance the adhesive strength. In particular, a chromic acid mixture containing dichromate and concentrated sulfuric acid is known as a chemical treating agent effective for improving the adhesive strength. However, the surface treatment requires a long time, and the work is complicated. For example, when the chromic acid mixed solution is used, it takes a long time for the surface treatment, and since it is a strong oxidant, there are problems that it is highly dangerous and that the waste liquid treatment is difficult. Further, Japanese Patent Application Laid-Open No. 3-38221 discloses that a polyolefin-based hollow fiber is surface-treated with an oxidizing agent, but the work is complicated like the above.

Further, when a gas dissolved in a liquid such as water is removed by using a porous membrane, the porous membrane is required to be impermeable to liquid and selectively permeable to gas. However, when the surface treatment of the porous membrane is performed, the portion effective for membrane separation is also surface-treated, and is easily hydrophilized. Therefore, there is a risk that the liquid permeates through the hydrophilized portion. Therefore, surface treatment is not suitable for separation membranes and the like.

Japanese Unexamined Patent Publication (Kokai) No. 3-68427 proposes a membrane separation module in which 50% or more of micropores in the membrane are filled with a potting material at the ends of a plurality of fluorine-based porous hollow separation membranes. In this membrane separation module, the surface of the fluorine-based porous hollow separation membrane is treated with an organic solvent having a small surface tension to retain the organic solvent in the fine pores of the fluorine-based porous hollow separation membrane, and then in this state. It is manufactured by applying a potting material and allowing the potting material to penetrate into the fine holes.

However, since the organic solvent used in this method exhibits volatility, the amount of the organic solvent in the fine pores may fluctuate depending on the processing conditions, and high sealing performance may not be surely imparted. Moreover, since the treatment is performed with the organic solvent and the potting material is injected, the end portion of the separation membrane cannot be sealed by a simple operation, and the work is complicated.

In the hollow fiber type membrane module, a urethane-based adhesive is generally used as an end sealing adhesive. However, since urethane adhesives generally have low heat resistance and chemical resistance and are easily impaired in sealing property, they are used only for membrane modules used at room temperature.

Japanese Examined Patent Publication No. 3-47887, Japanese Examined Patent Publication No. 3-
No. 64174, JP-A-1-289884, and JP-A-3-188927 disclose hollow fiber membrane modules using an epoxy-based adhesive containing a bisphenol A type epoxy resin having relatively high heat resistance. ing. Further, JP-A-4-83518 discloses a porous membrane module using a potting agent containing a bisphenol type epoxy resin and bis (p-aminocyclohexyl) methane.

However, even if the hollow fiber of the polyolefin or the fluorine-containing polymer is porous and has a rough surface, the aromatic epoxy resin has a small adhesive property, and thus a sealing property.
Therefore, when the fluid to be treated is subjected to membrane separation under high temperature and high pressure using the membrane module, the fluid to be treated leaks from the sealing portion within a short time, and the membrane separation operation cannot be continued.

[0012] These problems are not limited to separation membranes such as hollow fibers and flat membranes, but occur similarly when adhering adherends having a low energy surface containing polyolefin, fluorine-containing polymer and the like.

[0013]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an epoxy adhesive which exhibits high adhesion to an adherend having a low energy surface without surface treatment. .

Another object of the present invention is to provide an epoxy adhesive having high heat resistance.

Still another object of the present invention is to provide a bonding method capable of obtaining high adhesion even to an adherend having a small surface energy.

Another object of the present invention is to provide a membrane module which is sealed with a potting agent having excellent adhesion and heat resistance to a separation membrane having a small surface energy and which can be stably used for a long period of time even under high temperature and high pressure. It is in.

[0017]

The present inventor has conducted extensive studies in order to achieve these objects, and as a result, mainly uses olefin polymers,
The present invention has been completed by finding that the non-aromatic epoxy compound has a high adhesive force even on an adherend having a rough surface containing a fluorine-containing polymer or the like as required.

That is, the epoxy adhesive of the present invention is
It is an adhesive mainly composed of an olefin-based polymer and applied to adhesion of an adherend having a rough surface, which contains a non-aromatic epoxy compound.

The present invention also provides an adherend having a rough surface,
An adhesion method of adhering with the epoxy adhesive having a contact angle of 60 ° or less; a membrane-containing structure in which at least a part of the porous membrane is adhered with the epoxy adhesive; and a porous hollow fiber membrane Provided is a membrane module in which an end of an adherend is sealed with the epoxy adhesive.

The above-mentioned epoxy compound has a non-aromatic compound having at least one epoxy group, preferably two or more epoxy groups in the molecule and containing no aromatic ring, for example, an aliphatic epoxy compound or an oil. Included are cyclic epoxy compounds and alicyclic aliphatic epoxy compounds. The epoxy compound, epichlorohydrin, a compound having an active hydrogen atom, for example, a glycidyl ether type epoxy compound, a glycidyl ester type epoxy compound, a glycidyl amine type obtained by reacting with a compound having a hydroxy group, a carboxy group, an amino group or the like. Epoxy compounds: Epoxy compounds having double bonds oxidized with an oxidizing agent such as peracetic acid are included.

As the aliphatic epoxy compound, for example,
Glycidyl ether type epoxy compounds such as ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, and glycerin triglycidyl ether; polyvalent carboxylic acids such as dimer acid and their anhydrides as raw materials And a glycidyl amine epoxy compound prepared from an aliphatic amine as a raw material.

Generally, when an aliphatic epoxy compound is used, there is a problem that the heat resistance of the cured product becomes low. In such a case, an epoxy compound having three or more epoxy groups,
For example, it is preferable to use glycerin triglycidyl ether or the like because heat resistance can be increased.

Examples of the alicyclic epoxy compound and the alicyclic aliphatic epoxy compound include hydrogenated bisphenol A.
Type epoxy resin, hydrogenated bisphenol F type epoxy resin, hydrogenated bisphenol AD type epoxy resin, hydrogenated bisphenol S type epoxy resin, hydrogenated phenol novolac type epoxy resin, hydrogenated cresol novolac type epoxy resin, tetrakis (glycidyloxycyclohexyl) Ethane, 1,2-diglycidyloxycyclohexane, 1,3-diglycidyloxycyclohexane, 1,
Glycidyl ether type epoxy compounds such as 4-diglycidyloxycyclohexane; diglycidyl tetrahydrophthalate, diglycidyl hexahydrophthalate,
Glycidyl ester type epoxy compounds such as dimethylglycidyl hexahydrophthalate; N, N-diglycidylaminocyclohexane, 2-methyl-N, N-diglycidylaminocyclohexane, N, N-diglycidyl-
4-glycidyloxycyclohexane, 1,1-bis (4-N, N-diglycidylaminocyclohexyl) methane, 1,2-bis (N, N-diglycidylaminomethyl) cyclohexane, 1,3-bis (N, Glycidylamine type epoxy compounds such as N-diglycidylaminomethyl) cyclohexane and 1,4-bis (N, N-diglycidylaminomethyl) cyclohexane; cyclohexene rings such as alicyclic diepoxy acetal and alicyclic diepoxy adipate And an alicyclic epoxy compound in which the double bond of is oxidized.

Other epoxy compounds include heterocyclic epoxy compounds such as triglycidyl isocyanurate;
Hydantoin type epoxy compounds such as diglycidyl hydantoin and glycidyl glycidoxyalkyl hydantoin; 3,9-bis (3-aminopropyl) -2,4
Also included are spiro ring-containing epoxy compounds made from 8,10-tetraoxaspiro [5.5] undecane and the like as raw materials.

These epoxy compounds can be used alone or as a mixture of two or more kinds.

The above-mentioned epoxy compound, if necessary,
A monofunctional reactive diluent such as butyl glycidyl ether or allyl glycidyl ether may be added.

Among the above epoxy compounds, aliphatic epoxy compounds, alicyclic epoxy compounds, and alicyclic aliphatic epoxy compounds, especially alicyclic or alicyclic aliphatic compounds having cyclohexane units, have a low energy surface. It has particularly high affinity and adhesion to an adherend, for example, an adherend containing polyolefin, and high heat resistance. Examples of the cyclohexane unit include a tetrahydrophthalate unit and the following units.

[0028]

[Chemical 2] (In the formula, R ¹ and R ² are the same or different and each represents a hydrogen atom or a methyl group.) The glycidyl amine type epoxy compound gives a cured product having high heat resistance. In particular, the glycidyl amine type epoxy compound containing a cyclohexane unit, and above all, the glycidyl amine type epoxy compound having 2 to 4 glycidyl groups produces a cured product having high heat resistance as well as affinity and adhesion to an adherend. To do.
Examples of such epoxy compounds include 1,2-bis (N, N-diglycidylaminomethyl) cyclohexane, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, and 1,4-bis ( N, N-diglycidylaminomethyl) cyclohexane and the like are included. Particularly preferred epoxy compounds include 1,3-bis (N, N
-Diglycidylaminomethyl) cyclohexane and the like.

The glycidyl ether type epoxy compound containing a cyclohexane unit gives a cured product having appropriate flexibility.

Such an epoxy compound may be used in combination with an epoxy compound having an aromatic ring as long as the adhesiveness is not impaired. The aromatic epoxy compounds include, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin and the like. The ratio of the non-aromatic epoxy compound to the aromatic epoxy compound is the ratio of the non-aromatic epoxy compound /
Aromatic epoxy compound = 25-100 / 75-0 (weight ratio), preferably 35-100 / 65-0 (weight ratio)
Is. When the proportion of aromatic epoxy compound increases,
The adhesive strength is reduced.

The epoxy adhesive of the present invention contains a conventional curing agent and / or curing accelerator. These compounds can be appropriately selected depending on the kind of the epoxy compound. The curing agent includes an amine-based curing agent, a polyaminoamide-based curing agent obtained by reacting a polyvalent carboxylic acid such as dimer acid with a polyalkylene polyamine, an acid or acid anhydride-based curing agent, and the like.

Examples of the amine-based curing agent include aliphatic amines such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropylenediamine and hexamethylenediamine; mensendiamine, isophoronediamine, diaminodicyclohexylmethane, bis. Alicyclic amines such as (4-amino-3-methylcyclohexyl) methane and 1,3-bis (aminomethyl) cyclohexane; 2,4-diaminotoluene, p-phenylenediamine, m-phenylenediamine, p-xylylenediene Monocyclic aromatic diamines such as amines, m-xylylenediamine and tetrachloro-p-xylylenediamine; 3,5-diamino-4-chlorobenzoic acid alkyl ester; 4,4′-diaminodiphenylmethane, 3,3 ′ Dichloro-4,4'-diaminodiphenylmethane, diaminodiphenylmethane, such as 3,3'-diethyl-4,4'-diaminodiphenylmethane;
Diaminodiphenyl sulfone such as 4,4′-diaminodiphenyl sulfone and 3,3′-dimethyl-4,4′-diaminodiphenyl sulfone; 4,4′-diaminodiphenyl ether; Heterocyclic amine such as N-aminoethylpiperazine; 3,9-bis (3-aminopropyl)-
Examples include spirocyclic amines such as 2,4,8,10-tetraoxaspiro [5.5] undecane.

Examples of the acid or acid anhydride type curing agent include aliphatic carboxylic acid anhydrides such as dodecenyl succinic anhydride, polyadipic acid anhydride polyazelaic acid anhydride, and polysebacic acid anhydride, and their carboxylic acids; methyl tetrahydro. Alicyclic carboxylic acid anhydrides such as phthalic anhydride, methylhexahydrophthalic anhydride, methylhymic acid anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylcyclohexene dicarboxylic acid anhydride, and hettanic anhydride, and their carboxylic acids And aromatic carboxylic acid anhydrides such as phthalic anhydride, trimellitic anhydride, pyromellitic dianhydride, benzophenonetetracarboxylic acid anhydride, and tetrabromophthalic anhydride, and their carboxylic acids.

The curing agent also includes basic active hydrogen compounds such as dicyandiamide and organic acid dihydrazides such as adipic acid dihydrazide.

Among these curing agents, aromatic compounds having high heat resistance, particularly aromatic amines are preferable. When combined with the epoxy compound having the cyclohexane unit, aliphatic amine, alicyclic amine and the like are also preferable. The curing agent can be used alone or as a mixture of two or more kinds.

The ratio of the epoxy compound to the curing agent is
It can be appropriately selected depending on the epoxy equivalent of the epoxy compound, the structure of the curing agent and the number of functional groups. The ratio of the epoxy compound to the curing agent is, for example, an equivalent ratio of the functional group of the curing agent to the epoxy group is 0.3 to 1.5, preferably 0.5.
It is about 1.1.

As the curing accelerator, a conventional compound such as tris (dimethylaminomethyl) phenol, 1,
8-diazabicyclo [5,4,0] undecene-7 (D
BU), 1,5-diazabicyclo [4.3.0] nonene-5 (DBN), 1,4-diazabicyclo [2.2.
2] Tertiary amines such as octane (DABCO), imidazoles, Lewis acids, Bronsted acids and the like.

Further, the epoxy adhesive may contain various additives such as a filler, an antioxidant and a reinforcing agent, if necessary.

The epoxy adhesive may have a viscosity in a range that does not impair the adhesion workability. For example, when the epoxy adhesive is injected into the sealing portion of the membrane module, the viscosity of the epoxy adhesive is, for example, 50 to 10000 cps, preferably 100 to 1000 cps. The epoxy adhesive may contain an organic solvent, if necessary.

The preferred epoxy adhesive has a contact angle with the adherend of 60 ° or less, preferably 57 ° or less.

The epoxy adhesive of the present invention exhibits high adhesiveness to various adherends and is suitably applied to adherends having a low energy surface. As the adherend having a low energy surface, the critical surface tension is 10 to 35 dyne /
A polymer having cm, for example, an adherend mainly composed of an olefin-based polymer can be mentioned. A preferred epoxy adhesive is for an adherend having a low energy surface,
The contact angle is 60 ° or less, preferably about 25 to 57 °.

The contact angle means the contact angle on the flat surface of the flat plate made of the material forming the adherend.

Examples of the olefin polymer include:
Polyethylene, ethylene-propylene copolymer, ethylene-ethyl acrylate copolymer, ethylene-vinyl acetate copolymer, ionomer, polypropylene, polymer having unsaturated bond (for example, poly-4-methylpentene-
1) etc. are illustrated.

The adherend may mainly contain an olefin polymer, and other polymers such as polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, tetrafluoroethylene-ethylene copolymer, One or more fluorine-containing polymers such as a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer may be contained.

The preferred polymer has a critical surface tension of 20.
Polymers of about ~ 35 dyne / cm, for example, polyethylene, ethylene-propylene copolymer, polypropylene, poly-4-methylpentene-1, etc., especially polypropylene, etc. are included.

The adherend is made of the above-mentioned olefinic polymer 5
It is contained in an amount of 0% by weight or more, preferably 75% by weight or more.

The adherend has a rough surface. Such adherends include, for example, porous adherends such as porous membranes. When the epoxy-based adhesive is applied to the porous adherend, high adhesion strength is exhibited without increasing the surface treatment of the adherend, together with the increase in the adhesive surface area due to the uneven surface and the anchor effect.

Particularly preferred adherends are porous membranes, especially porous hollow fiber membranes. When such a porous film is adhered with the above-mentioned epoxy adhesive, the adhesive surface area is further increased, and the adhesive strength practically poses no problem. In particular, it exhibits a high adhesive force for porous hollow fiber membranes.

The surface roughness of the adherend, the structure of the porous membrane and the pore diameter of the hollow fiber membrane are not particularly limited, and can be selected according to the separation method and the type of separation component. The surface roughness of the adherend is, for example, 0.01 μm or more when the depth of the uneven portion is
Preferably 0.05 to 10 μm, more preferably 1 to
It may be about 5 μm. Further, when the dissolved gas in the liquid is separated, the pore diameter of the porous membrane is, for example, 0.001.
The thickness is not less than μm, preferably 0.01 to 5 μm, and more preferably about 0.05 to 1 μm.

In the method of the present invention, an adherend having a rough surface such as a porous membrane, preferably the end of a porous hollow fiber membrane is adhered with the epoxy adhesive. Adhesion is performed by interposing an epoxy adhesive between the adherends having the rough surface,
This can be done by curing the epoxy compound.

The epoxy adhesive is preferably cured by contacting the adherend with a contact angle of 60 ° or less. In particular, under heating, for example, 30 ° C to less than the curing temperature,
It is preferable to apply the epoxy adhesive to the adherend at about 45 to 75 ° C. At that time, the epoxy adhesive may be applied to the adherend or the epoxy adhesive and / or the adherend may be heated in a warm atmosphere. When the epoxy adhesive is applied to the adherend under heating, the adhesive strength can be easily increased.

If necessary, the adherend may be used for adhesion after cleaning the surface, and is subjected to surface treatment such as treatment with an organic solvent, plasma discharge treatment, corona discharge treatment, ozone treatment and the like. After that, you may offer to adhesion.

Curing can be appropriately selected depending on the type of curing agent, the heat resistant temperature of the adherend, and the like, for example, room temperature to 1
It can be performed at about 50 ° C. The epoxy adhesive may be cured at a low temperature and then further cured.

In the membrane-containing structure and membrane module of the present invention, a porous membrane, preferably a porous hollow fiber membrane, is used as the adherend. The ends of the porous hollow fiber membrane are adhesively sealed with the epoxy adhesive.

As the polymer constituting the porous film, in addition to the olefin polymer and the fluorine-containing polymer, various polymers, for example, cellulose polymers such as cellulose acetate; polyvinyl chloride; acrylonitrile polymers; acrylic polymers. Polymer; Silicone resin; Polyamide; Polyimide; Polyethersulfone;
Examples include polysulfone; polyphenylene oxide; polyphenylene sulfide; polyarylate; polyetheretherketone; polyetherimide; polycarbonate; polyvinyl alcohol-based polymers. When separating dissolved gas in a liquid, preferred porous membranes include
Porous membranes such as olefin-based polymers, fluorine-containing polymers, polyether sulfones, polysulfones, etc. are included. Particularly preferred porous membranes include olefin polymer porous membranes.

In the membrane-containing structure and the membrane module, the porous membrane may be treated with an organic solvent, a plasma discharge treatment, a treatment with an organic solvent, if necessary, as long as the separation characteristics are not impaired.
Surface treatment such as corona discharge treatment and ozone treatment may be performed.

A membrane separation module having a hollow fiber membrane usually comprises a hollow fiber bundle composed of a plurality of hollow fiber membranes and a case for accommodating the hollow fiber bundle. In such a hollow fiber membrane module, both ends of the hollow fiber bundle may be adhesively sealed with the epoxy adhesive in a state where the end faces of the hollow fiber membrane are open.

In such a membrane-containing structure or membrane module, the case has a hollow cylindrical case body and a supply port for closing one opening of the case body and for supplying a fluid. And a lid body that closes the other opening of the case body and has an outlet for letting out a concentrated component that has not permeated the hollow fiber membrane. . Also, in the case body,
Usually, an outlet is formed on the permeate side of the hollow fiber membrane, that is, on the secondary side to let out the component selectively permeated.

The material of the case is not particularly limited, and may be plastic or metal. Further, the case may be arranged such that the permeate side can be depressurized through the outlet and the chamber can be vented and can be depressurized, if necessary.

In such a membrane-containing structure or hollow fiber membrane module, a hollow fiber bundle composed of a plurality of hollow fiber membranes is housed in a case, and at least one end face of both end faces of the hollow fiber membrane is opened. In this state, the hollow fiber membranes on the end face opening side and the end portion of the case are bonded and sealed with a sealant.

The method for injecting the epoxy adhesive is a conventional method, for example, while rotating the case,
A centrifugal injection method of injecting into the ends of the hollow fiber bundle and the case can be adopted.

By heating and curing the injected sealing agent, a membrane module in which the hollow fiber membrane is firmly fixed to the sealing portion can be obtained. The heat curing temperature can be selected according to the type of the porous film, and is usually room temperature to about 150 ° C.

The membrane-containing structure or the hollow fiber membrane should have at least one end face open. For example, one end of the plurality of hollow fiber membranes may be adhesively sealed with a sealing part in a state where the end face is open, and the hollow portion of the other end of the hollow fiber membrane may be closed. Also, with both end portions of the plurality of hollow fiber membranes converged, with the end faces of the hollow fiber membranes open,
The focusing portion may be adhesively sealed.

Further, the membrane-containing structure and the membrane module may be provided with no case, and at least one end of the plurality of hollow fiber membranes may be adhesively sealed to each other and attachable to the case. In this case, the membrane module can be mounted in the case in a cartridge type.

Further, in the membrane-containing structure and the membrane module, the porous membrane is not limited to the hollow fiber membrane, but may be a sheet-like membrane such as a flat membrane or a spiral membrane. Further, the membrane module may be a tubular module, a spiral module, a flat plate module, a pleated module, or the like.

The preferred membrane module is as follows.

(1) The end of the porous hollow fiber membrane of an olefin polymer is sealed with an epoxy adhesive containing a non-aromatic epoxy compound (such as an aliphatic, alicyclic or aliphatic alicyclic epoxy compound). Membrane module.

(2) A membrane module in which the end of the porous hollow fiber membrane of olefin polymer is sealed with an epoxy adhesive containing an epoxy compound having a cyclohexane unit.

(3) The end of the porous hollow fiber membrane of olefin polymer is sealed with an epoxy adhesive containing a glycidyl amine type epoxy compound containing a cyclohexane unit or a glycidyl ether type epoxy compound containing a cyclohexane unit. Membrane module.

The membrane separation module of the present invention can be used, for example, for membrane separation of liquid, membrane separation of gas component from liquid, and the like.

[0071]

The epoxy adhesive of the present invention exhibits high adhesion to an adherend having a low energy surface and a rough surface without surface treatment.

An adhesive containing an epoxy compound having a cyclohexane unit or an epoxy adhesive showing a contact angle of 60 ° or less with respect to an adherend has a higher adhesion to an adherend having a low energy surface. Shows sex.

Further, the epoxy-based adhesive exhibits a higher adhesive force to the adherend of the porous membrane, particularly the hollow fiber membrane.

According to the method of the present invention, even an adherend having a small surface energy can be firmly bonded.

Further, according to the membrane-containing structure or membrane module of the present invention, the epoxy adhesive having excellent adhesiveness and heat resistance can firmly bond and seal even a separation membrane having a small surface energy, and can be heated at a high temperature. It can be used stably for a long time even under high pressure.

[0076]

EXAMPLES The present invention will be described in more detail based on the following examples.

Example 1 (1) On a porous polypropylene flat membrane having a pore size of about 0.1 μm on its surface [Celgard 2400, manufactured by Daicel Chemical Industries, Ltd.] in an atmosphere at a temperature of 50 ° C., 1,3- Bis (N, N-diglycidylaminomethyl) cyclohexane [Mitsubishi Gas Chemical Co., Inc., TETRAD-C] and α, α '
One drop of an epoxy adhesive (mixing ratio: epoxy group / amine active hydrogen = 1/1 equivalent) mixed with -diamino-m-xylene [Tokyo Kasei Co., Ltd.] was dropped and cured at 50 ° C.

After curing, the contact angle between the flat film and the interface of the adhesive was measured on the basis of a micrograph, and it was 42 °.

(2) Porous polypropylene hollow fiber membrane having a pore size of about 0.1 μm on the surface [Daicel Chemical Industry Co., Ltd., Celgard X-10, inner diameter 240 μm, outer diameter 3
00 μm] 2000 pieces in a cylindrical case made of polycarbonate (inner diameter 22 mm, outer diameter 26 mm, length 106 cm)
, The epoxy adhesive was injected into both ends of the hollow fiber membrane, and the adhesive was cured at 50 ° C. to seal both ends of the hollow fiber membrane. After post-curing at 100 ° C. for 15 hours, both ends to which excess adhesive had adhered were cut, and both ends of the hollow fiber membrane were opened to produce a hollow fiber membrane module.

Then, when hot water of 80 ° C. was passed through the membrane module at a pressure of 2 kg / cm ² for 20 hours, no liquid leakage from the adhesive sealing part occurred.

Example 2 (1) A mixture of 50% by weight of the epoxy compound used in Example 1 and 50% by weight of a bisphenol A type epoxy resin [Yukaka Shell Epoxy Co., Ltd., Epicoat 815] was added.
α, α'-diamino-m-xylene [Tokyo Kasei Co., Ltd.]
In an epoxy group / amine active hydrogen = 1/1 equivalent,
An epoxy adhesive was prepared.

The contact angle of the obtained adhesive with the flat film was
When measured in the same manner as in Example 1 (1), it was 45 °.

(2) A membrane module was prepared in the same manner as in Example 1 (2) except that the above epoxy adhesive was used instead of the adhesive in Example 1 (1), and hot water at 80 ° C. was applied at a pressure of 2 k.
When water was passed at g / cm ² for 20 hours, no liquid leaked from the adhesively sealed portion.

Example 3 (1) To a mixture of 40% by weight of the epoxy compound used in Example 1 and 60% by weight of a bisphenol A type epoxy resin [Yukaka Shell Epoxy Co., Epicoat 828] was added.
α, α'-diamino-m-xylene [Tokyo Kasei Co., Ltd.]
In an epoxy group / amine active hydrogen = 1/1 equivalent,
An epoxy adhesive was prepared.

The contact angle of the obtained adhesive with the flat film was
When measured in the same manner as in Example 1 (1), it was 55 °.

(2) A membrane module was prepared in the same manner as in Example 1 (2) except that the above epoxy adhesive was used instead of the adhesive in Example 1 (1), and hot water at 80 ° C. was applied at a pressure of 2 k.
When water was passed at g / cm ² for 20 hours, no liquid leaked from the adhesively sealed portion.

Comparative Example 1 (1) In place of the epoxy compound used in Example 1, bisphenol A type epoxy resin [Eikate Shell Epoxy Co., Ltd., Epikote 828] was added with α, α'-diamino-.
m-xylene [Tokyo Kasei Co., Ltd.] was mixed at an epoxy group / amine active hydrogen = 1/1 equivalent to prepare an epoxy adhesive.

The contact angle of the obtained adhesive with the flat film was
When measured in the same manner as in Example 1 (1), it was 68 °.

(2) Example 1 Instead of the adhesive of (1),
A membrane module was prepared in the same manner as in Example 1 (2) except that the above epoxy adhesive was used, and hot water at 80 ° C. was applied under pressure 2
was 20 hours through water kg / cm ^2, after passing the start of water,
After 5 hours, liquid leakage occurred between the hollow fiber membrane and the adhesive sealing part.

Further, when hot water at 50 ° C. was passed through the membrane module produced in the same manner as above at a pressure of 1 kg / cm ² for 20 hours, 10 hours later, it was removed from between the hollow fiber membrane and the adhesive sealing portion. A liquid leak has occurred.

Comparative Example 2 (1) In place of the epoxy compound used in Example 1, a bisphenol A type epoxy resin [Epicoat 828, manufactured by Yuka Shell Epoxy Co., Ltd.] was used. Bis (3-aminopropyl) -2,4,8,
10-Tetraoxaspiro [5.5] undecane was mixed at an epoxy group / amine active hydrogen = 1/1 equivalent to prepare an epoxy adhesive.

The contact angle of the obtained adhesive with the flat film was
When measured in the same manner as in Example 1 (1), it was 67 °.

(2) Example 1 Instead of the adhesive of (1),
A membrane module was prepared in the same manner as in Example 1 (2) except that the above epoxy adhesive was used, and hot water at 80 ° C. was applied under pressure 2
was 20 hours through water kg / cm ^2, after passing the start of water,
After 5 hours, liquid leakage occurred between the hollow fiber membrane and the adhesive sealing part.

Comparative Example 3 (1) Instead of the epoxy compound used in Example 1, a urethane adhesive was used. This urethane-based adhesive was prepared by mixing a urethane prepolymer [Nippon Polyurethane Co., Ltd., Coronate 4403] and a curing agent [Nippon Polyurethane Co., Ltd., Nipporan 4221].

The contact angle of the obtained adhesive with the flat film was
When measured in the same manner as in Example 1 (1), it was 32 °.

(2) Example 1 Instead of the adhesive of (1),
A membrane module was prepared in the same manner as in Example 1 (2) except that the above urethane-based adhesive was used, and hot water at 80 ° C. was applied under a pressure of 2.
was 20 hours through water kg / cm ^2, after passing the start of water,
After the lapse of 5 hours, the adhesive sealing portion was cracked and liquid leakage occurred.

Example 4 (1) The epoxy compound used in Example 1 was mixed with triethylenetetramine [Wako Pure Chemical Industries, Ltd.] at an epoxy group / amine active hydrogen = 1/1 equivalent to give an epoxy adhesive. Prepared.

The contact angle of the obtained adhesive with the flat film was
When measured in the same manner as in Example 1 (1), it was 44 °.

(2) A membrane module was prepared in the same manner as in Example 1 (2) except that the epoxy adhesive was used instead of the adhesive in Example 1 (1), and hot water at 80 ° C. was applied at a pressure of 2 k.
When water was passed at g / cm ² for 20 hours, no liquid leaked from the adhesively sealed portion.

Example 5 (1) Hydrogenated bisphenol A type diglycidyl ether [Toto Kasei Co., Ltd., ST-3000] was mixed with α, α'-diamino-m-xylene [Tokyo Kasei Co., Ltd.] as an epoxy group /
An epoxy-based adhesive was prepared by mixing amine active hydrogen at 1/1 equivalent. The contact angle of the obtained adhesive with the flat film was measured in the same manner as in Example 1 (1).
It was °.

(2) A membrane module was prepared in the same manner as in Example 1 (2) except that the above epoxy adhesive was used instead of the adhesive in Example 1 (1), and hot water at 50 ° C. was applied at a pressure of 1 k.
When water was passed at g / cm ² for 20 hours, no liquid leaked from the adhesively sealed portion.

Example 6 (1) Hydrogenated bisphenol A type diglycidyl ether [Toto Kasei Co., Ltd., ST-3000] was mixed with triethylenetetramine [Wako Pure Chemical Industries, Ltd.] as an epoxy group / amine active hydrogen = 1 / An epoxy adhesive was prepared by mixing 1 equivalent.

The contact angle of the obtained adhesive with the flat film was
When measured in the same manner as in Example 1 (1), it was 40 °.

(2) A membrane module was prepared in the same manner as in Example 1 (2) except that the epoxy adhesive was used instead of the adhesive in Example 1 (1), and hot water at 50 ° C. was applied at a pressure of 1 k.
When water was passed at g / cm ² for 20 hours, no liquid leaked from the adhesively sealed portion.

Example 7 (1) Glycerin triglycidyl ether [Tohto Kasei Co., Ltd., YH-300] was mixed with α, α'-diamino-m-xylene [Tokyo Kasei Co., Ltd.] as an epoxy group / amine active hydrogen. Epoxy adhesives were prepared by mixing in 1/1 equivalent.

The contact angle of the obtained adhesive with the flat film was
When measured in the same manner as in Example 1 (1), it was 44 °.

(2) A membrane module was prepared in the same manner as in Example 1 (2) except that the epoxy adhesive was used instead of the adhesive in Example 1 (1), and hot water at 50 ° C. was applied at a pressure of 1 k.
When water was passed at g / cm ² for 20 hours, no liquid leaked from the adhesively sealed portion.

Example 8 (1) Triethylenetetramine (Wako Pure Chemical Industries, Ltd.) was added to glycerin triglycidyl ether [Tohto Kasei Co., Ltd., YH-300] with an epoxy group / amine active hydrogen = 1/1.
Epoxy adhesives were prepared by mixing in equal amounts.

The contact angle of the obtained adhesive with the flat film was
When measured in the same manner as in Example 1 (1), it was 42 °.

(2) A membrane module was prepared in the same manner as in Example 1 (2) except that the above epoxy adhesive was used instead of the adhesive in Example 1 (1), and hot water at 50 ° C. was applied at a pressure of 1 k.
When water was passed at g / cm ² for 20 hours, no liquid leaked from the adhesively sealed portion.

Comparative Example 4 (1) Epoxy group / amine active hydrogen = 1 in the same manner as in Comparative Example 1 except that triethylenetetramine [Wako Pure Chemical Industries, Ltd.] was used instead of the curing agent used in Comparative Example 1. An epoxy adhesive was prepared by mixing in an amount of 1 equivalent.

The contact angle of the obtained adhesive with the flat film was
When measured in the same manner as in Example 1 (1), it was 67 °.

(2) A membrane module was prepared in the same manner as in Example 1 (2) except that the above epoxy adhesive was used instead of the adhesive in Example 1 (1), and hot water at 50 ° C. was applied at a pressure of 1 k.
was 20 hours through water in g / cm ^2, after passing the start of water, 1
After 2 hours, liquid leakage occurred between the hollow fiber membrane and the adhesive sealing part.

Example 9 (1) 40% by weight of hydrogenated bisphenol A type diglycidyl ether [Toto Kasei Co., Ltd., ST-3000] and bisphenol A type epoxy resin [Okaka Shell Epoxy Co., Epicoat 828] 60 In a mixture with wt%,
α, α'-diamino-m-xylene [Tokyo Kasei Co., Ltd.]
In an epoxy group / amine active hydrogen = 1/1 equivalent,
An epoxy adhesive was prepared.

The contact angle of the obtained adhesive with the flat film was
When measured in the same manner as in Example 1 (1), it was 53 °.

(2) A membrane module was prepared in the same manner as in Example 1 (2) except that the above epoxy adhesive was used instead of the adhesive in Example 1 (1), and hot water at 50 ° C. was applied at a pressure of 2 k.
When water was passed at g / cm ² for 20 hours, no liquid leaked from the adhesively sealed portion.

Claims (9)

[Claims] 1. An epoxy adhesive which is mainly composed of an olefin polymer and is applied to adhere to an adherend having a rough surface, the epoxy adhesive containing a non-aromatic epoxy compound. 2. The epoxy adhesive according to claim 1, wherein the epoxy compound has a cyclohexane unit. 3. The epoxy compound has the following cyclohexane unit: The epoxy adhesive according to claim 1, wherein R ¹ and R ² are the same or different and each represents a hydrogen atom or a methyl group. 4. The epoxy adhesive according to claim 1, wherein the epoxy compound is a glycidyl amine type epoxy compound containing a cyclohexane unit or a glycidyl ether type epoxy compound containing a cyclohexane unit. 5. The epoxy adhesive according to claim 1, wherein the adherend is a porous membrane or a porous hollow fiber membrane. 6. An adherend mainly composed of an olefin polymer and having a rough surface has a contact angle of 60 ° or less.
5. An adhesion method for adhering with the epoxy adhesive according to any one of items 1 to 4. 7. The adhesion method according to claim 6, wherein the adherend is a porous membrane or a porous hollow fiber membrane. 8. The porous membrane according to claim 1, wherein at least a part of the porous membrane is formed.
A film-containing structure adhered by the epoxy adhesive according to any one of items 1 to 4. 9. A membrane module in which an end portion of an adherend made of a porous hollow fiber membrane is sealed with the epoxy adhesive according to any one of claims 1 to 4.