JPH06319960A - Hollow fiber membrane module - Google Patents

Abstract

PURPOSE:To provide a hollow fiber membrane module which can be used always at high temperatures and whose range of application can be extended to a field in which the hollow fiber membrane module is normally used at high temperatures without causing damage to the membrane when the end part of the membrane is sealed to a case or when pressure is exerted on the module. CONSTITUTION:In a membrane module of the structure made up of the hollow fiber membrane which is arranged in a case and whose end part is sealed to the case with adhesive agent, its structure is of a laminate constituted of a heat resisting adhesive layer (A) formed with its adhesive part extending from the end of the hollow fiber in the lengthwise direction and consisting of a main epoxy agent having a glass transition point of 60-90 deg.C and a hardening agent and of an adhesive layer (B) consisting of a main epoxy agent having a glass transition point of 20-50 deg.C and a hardening agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to dust, protein, colloid, bacteria, ions, gas, etc. in various separation processes such as food industry, pharmaceutical industry, electronic industry, chemical industry, wastewater treatment, artificial organ, medical treatment and the like. It consists of microfiltration membrane, ultrafiltration membrane, reverse osmosis membrane, membrane for gas-liquid contact, degassing membrane, gas supply membrane, gas separation membrane, etc. The present invention relates to a hollow fiber membrane module.

[0002]

2. Description of the Related Art In recent years, in various fields, process innovation utilizing the characteristics of a separation membrane has been vigorously pursued.
However, it has not been put to practical use in the field where it is constantly used at a high temperature of 60 ° C. or higher. In order to be used at high temperatures, it goes without saying that the heat resistance of the separation membrane itself must be excellent, but the adhesive part that seals the case and the end of the separation membrane must also have heat resistance. I won't. This tendency is particularly remarkable in the case of a hollow fiber membrane in which a large amount of adhesive is used. However, although the heat resistance of the separation membrane itself has been energetically advanced in the past, there are few reports on the heat resistance of the adhesive portion.

As an adhesive conventionally used for the above-mentioned application,
Epoxy type, urethane type, silicon type, vinyl ester type, etc. are used, but epoxy type, which is excellent in heat resistance, solvent resistance, adhesiveness, etc., is most widely used.

However, the usual epoxy adhesive is 50
There is a limit to use at about ℃. It is known that the epoxy adhesive can be widely adjusted in heat resistance mainly by selecting a curing agent, and it is disclosed in Japanese Patent Publication No. 3-47887 and Japanese Patent Laid-Open No. 2-887.
As disclosed in JP-A-268815 and JP-A-4-83518, in order to improve heat resistance, an acid anhydride-based, aromatic polyamine-based, cycloaliphatic polyamine-based, or imidazole-based curing agent is used. Is common.

However, when these curing agents are used, the curing shrinkage of the adhesive is too large, so that the hollow fiber membrane is likely to be damaged when the case and the end of the hollow fiber membrane are sealed. Have.

Further, when pressure is applied to the hollow fiber membrane module at a high temperature of 60 ° C. or higher, since the adhesive portion has no flexibility,
There is a problem that stress is concentrated on the boundary portion of the adhesive portion of the hollow fiber membrane, and the hollow fiber membrane is easily damaged.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the drawbacks of the prior art and can be used at a high temperature of about 60 ° C. or more at all times, and when sealing the case and the end of the hollow fiber membrane, An object of the present invention is to provide a hollow fiber membrane module that does not cause damage to the hollow fiber membrane when pressure is applied to the hollow fiber membrane module.

[0008]

In order to solve the above problems, the inventors of the present invention have conducted intensive studies on combinations of adhesives having different heat resistances, and as a result, have completed the present invention.

That is, the present invention is a membrane module having a structure in which a hollow fiber membrane is arranged in a case and the case and the end of the hollow fiber membrane are sealed with an adhesive, and the adhesive part is hollow. Glass transition point 50 ° C from the end in the length direction of the yarn
It is intended to provide a membrane module having a structure in which the above heat-resistant adhesive layer (A) and then the adhesive layer (B) having a lower glass transition point are laminated in this order. .

The hollow fiber membrane used in the present invention is not particularly limited and includes microfiltration membranes, ultrafiltration membranes, reverse osmosis membranes, gas-liquid contacting membranes, degassing membranes, gas supply membranes, gas separation membranes, Any material such as a pervaporation membrane, a dialysis membrane, an ion exchange membrane may be used.

The hollow fiber membrane may be made of any material as long as it can always be used at a high temperature of 60 ° C. or higher. For example, polysulfone, polyether sulfone,
Examples thereof include polyimide, polypropylene, poly-4-methylpentene 1, polyacrylonitrile, and Teflon.

The case used in the present invention may be made of any material such as metal, glass, ceramic and synthetic resin. When it does not have adhesiveness with an adhesive, it can be used after applying a primer in advance.

The shape of the case is generally cylindrical, but any shape may be used as long as it is used in the hollow fiber membrane module. As the adhesive layer (A) and the adhesive layer (B) used in the present invention, epoxy-based, urethane-based, silicon-based, vinyl ester-based, unsaturated polyester-based, etc. can be used, but the heat resistance and resistance It is preferable to use an epoxy type which is excellent in solvent properties and adhesiveness.

The epoxy main agent of the epoxy adhesive is, for example, glycidyl of bisphenol A, bisphenol F, novolac phenol, brominated bisphenol A, phenol and other phenols, and alcohols such as butanol, allyl alcohol, glycerin and polypropylene glycol. Examples thereof include ether type epoxy resins, cycloaliphatic epoxy resins, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, hydantoin type epoxy resins, triglycidyl isocyanurate and the like.

When an epoxy adhesive is used for the adhesive layer (B), a chain aliphatic polyamine and / or a curing agent is used.
Alternatively, it is preferable to use a modified product thereof. Examples of the chain aliphatic polyamine used include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, iminobispropylamine, bis (hexamethylene) triamine, dimethylaminopropylamine, diethylaminopropylamine, aminoethyl. Ethanolamine, 1,3,5-trisaminomethylhexane, trimethylhexamethylenediamine, etc. and their polyamides, epoxy adducts,
Modifications such as cyanoethylation can be mentioned.

When an epoxy adhesive is used for the adhesive layer (A), one or more curing agents selected from the group consisting of cycloaliphatic polyamines, aromatic polyamines, imidazoles and modified products thereof as a curing agent. Is preferably used.

Examples of the cycloaliphatic polyamine include menthenediamine, isophoronediamine, bis (4-amino-3-methylcyclohexyl) methane, N-aminoethylpiperazine, bis (4-aminocyclohexyl) methane, 1,3- Examples thereof include bisaminomethylcyclohexane and modified products thereof.

Examples of aromatic polyamines include metaxylenediamine, metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone and the like, and modified products thereof.

As the imidazoles, 2-ethyl-4
-Methylimidazole, 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 1-benzyl-2-methylimidazole and the like and modified products thereof.

The glass transition of the adhesive layer is based on New Experimental Chemistry Course 19 Polymer Chemistry (II) 12.4-4 glass transition, and the glass transition of the polymer is related to the freezing / releasing of the chain motion of the amorphous part. It is a relaxation phenomenon. At the glass transition temperature, the coefficient of thermal expansion, heat capacity, elastic modulus, mechanical damping, refractive index, etc. show discontinuous changes. The adhesive layer is an amorphous polymer, which is hard and hard to be deformed at a glass transition temperature or lower, and is soft and easily bendable and an elastomer at a glass transition temperature or higher. The elastic modulus of the adhesive layer drops by a factor of 1000 or less as the temperature rises from below the glass transition region.

The glass transition temperature of the adhesive layer can be obtained as a change point of the heat capacity by differential thermal analysis (DTA) and differential scanning calorimetry (DSC). Also, mechanics measurements,
The glass transition temperature can also be obtained by viscoelasticity measurement.

The glass transition point of the heat resistant adhesive layer (A) in the present invention is 50 ° C. or higher, preferably 60 ° C. to 90 ° C. The glass transition point of the adhesive layer (B) is
It may be lower than the glass transition point of the heat resistant adhesive layer (A), but it is preferably 20 to 50 ° C.

There is no particular limitation on the thickness ratio (A) / (B) of the adhesive layer (A) and the adhesive layer (B) in the present invention. However, since the adhesive layer (A) has a role of exhibiting heat resistance, it is necessary to have a sufficient thickness,
The adhesive layer (B) does not need to have a thickness because it has a role of expressing a buffering action. Therefore, (A) / (B) is 80
It is preferably in the range of / 20 to 99/1.

In the present invention, a method of placing a hollow fiber membrane in a case, filling the hollow fiber membrane end portion with an adhesive, and then curing it to seal the case and the hollow fiber membrane end portion is a module type. Can be carried out by any suitable method. As an example, the hollow fiber membranes are bundled and inserted into a cylindrical case, caps are attached to both ends of the case, the adhesive is injected into the case end while rotating around the center of the case, and the case is rotated as it is. Continue to cure the adhesive.

In the present invention, the adhesive may be cured at room temperature, but it is preferably cured at a temperature higher than the temperature at which the membrane module is used. that time,
If the adhesive is cured at a high temperature from the beginning of curing, the heat generated by the curing of the adhesive is large, and it is necessary to use a case or a separation film having high heat resistance. In order to avoid the curing heat generation, it is preferable that the first step is solidification at 0 to 60 ° C. and then post-curing at 70 to 150 ° C.

[0026]

The present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited thereto.

Example 1 (Manufacture of Membrane Module) An inner diameter of 110 mm as a case,
A pipe made of a heat-resistant vinyl chloride resin having an outer diameter of 120 mm and a length of 500 mm was prepared, and 50,000 hollow polytetramethylpentene membranes having an inner diameter of 200 μm and an outer diameter of 280 μm were inserted into the case. Caps made of polypropylene were attached to both ends of the case and set in a centrifugal molding machine.

Adhesive layer (A): Epiclon 850 (Dainippon Ink and Chemicals, bisphenol A type epoxy resin) 200g, Epicron B-065 (Dainippon Ink and Chemicals, modified chain aliphatic polyamine) 38g, 1 , 3
-Preparation of a mixture of 16 g of bisaminomethylcyclohexane (the glass transition point of the cured product of the mixture was 60 ° C by DSC measurement) and 40 in an atmosphere of 40 ° C.
It was poured into a case rotated at 0 rpm. Rotation 5
It continued for hours. The thickness of this layer was 25 mm.

Adhesive layer (B): 20 g of Epicron 850 (Dainippon Ink and Chemicals, bisphenol A type epoxy resin) and 8 g of Epicron B-065 (Dainippon Ink and Chemicals, modified chain aliphatic polyamine) are mixed. Prepared (the glass transition point of the cured product of the mixture was 40 ° C. by DSC measurement), and 40
Pour into a case rotated at 0 rpm and rotate it for 5
It continued for hours. Remove the case from the centrifugal molding machine and
After post-curing for 10 hours in a constant temperature bath kept at ℃,
Hollow fiber membrane module 1 was obtained by cutting both ends. The thickness of this layer was 2 mm.

(Evaluation of Membrane Module) While hot water of 60 ° C. is caused to flow inside the hollow fiber of the obtained hollow fiber membrane module 1, pressurization of 0 kgf / cm ² · G and 5 kgf / cm ² G is alternately repeated. The test was performed 100,000 times, but no water leakage due to peeling of the adhesive from the case or breakage of the hollow fiber occurred.

Example 2 (Manufacture of Membrane Module) A case having an inner diameter of 110 mm,
Prepare a pipe made of polysulfone resin with an outer diameter of 120 mm and a length of 500 mm, and have an inner diameter of 650 μm and an outer diameter of 8 in the case.
8,000 hollow fiber porous membranes of 30 μm made of polysulfone were inserted. Caps made of polysulfone resin were attached to both ends of the case and set in a centrifugal molding machine.

Adhesive layer (A): A mixture of 200 g of Epicron 830 (Dainippon Ink and Chemicals, bisphenol F type epoxy resin), 15 g of triethylenetetramine, and 15 g of metaxylenediamine (glass transition of the cured product of the mixture) The point was 70 ° C. according to the DSC measurement) was prepared and poured into a case rotated at 400 rpm in an atmosphere of 40 ° C. Immediately after the pouring was completed, the ambient temperature was raised to 50 ° C. and the rotation was continued for 5 hours.
The thickness of this layer was 25 mm.

Adhesive layer (B): A mixture of 20 g of Coronate 4403 (manufactured by Nippon Polyurethane Industry Co., Ltd., urethane resin main agent) and 15 g of Nipporan 4221 (manufactured by Nippon Polyurethane Industry Co., Ltd., urethane resin curing agent) (glass of cured product of the mixture) The transition point was 0 ° C. or lower according to the DSC measurement), poured into a case rotated at 400 rpm in an atmosphere of 50 ° C., the rotation was continued for 5 hours, and then the case was taken out from the centrifugal molding machine. The hollow fiber membrane module 2 was obtained by post-curing for 10 hours in a constant temperature bath kept at ° C. The thickness of this layer was 2 mm.

(Evaluation of Membrane Module) Pressurization of 0 kgf / cm ² · G and 5 kgf / cm ² G is alternately repeated while flowing hot water at 70 ° C. inside the hollow fiber of the obtained hollow fiber membrane module 2. The test was performed 100,000 times, but no water leakage due to peeling of the adhesive from the case or breakage of the hollow fiber occurred.

Example 3 (Production of Membrane Module) In the adhesive layer (A), the atmospheric temperature at the time of injecting the adhesive is 50 ° C., and the adhesive layer (B) is post-cured after sealing. A hollow fiber membrane module 3 was obtained in the same manner as in Example 1 except that it was not present. The thickness of the adhesive layers (A) and (B) was the same as in Example 1.

(Evaluation of Membrane Module) Pressurization of 0 kgf / cm ² · G and 5 kgf / cm ² G is alternately repeated while flowing hot water at 60 ° C. inside the hollow fiber of the obtained hollow fiber membrane module 3. The test was performed 100,000 times, but no peeling of the adhesive from the case or water leakage occurred.

Example 4 (Production of Membrane Module) As an adhesive layer (A), 200 g of Epicron 850 (a bisphenol A type epoxy resin manufactured by Dainippon Ink & Chemicals, Inc.) and Epicuron B-065 are used.
(Dai Nippon Ink Chemical Co., Ltd., modified chain aliphatic polyamine) 65 g, 2-ethyl 4-methyl imidazole 8 g mixed (the glass transition point of the cured product of the mixture is D
A membrane module 4 was obtained in the same manner as in Example 1 except that the temperature was 70 ° C. according to SC measurement). Adhesive layer (A)
The thicknesses of (B) and (B) were the same as in Example 1.

(Evaluation of Membrane Module) While flowing hot water of 70 ° C. into the obtained hollow fiber membrane module 4, 0 k
A test of alternately repeating pressurization of gf / cm ² · G and 5 kgf / cm ² G was performed 50,000 times.
No water leakage occurred.

[Comparative Example 1] A hollow fiber membrane module 5 was prepared in the same manner as in Example 1 except that the adhesive layer (B) was not prepared.
Got

(Evaluation of Membrane Module) While hot water of 60 ° C. is caused to flow inside the hollow fiber of the obtained hollow fiber membrane module 5, pressurization of 0 kgf / cm ² · G and 5 kgf / cm ² G is alternately repeated. When the test was conducted, water leakage occurred after 10,000 times.

[Comparative Example 2] As the adhesive layer (A), 200 g of Epicron 830 (Dainippon Ink and Chemicals, bisphenol F type epoxy resin), Epicron B-050
80 g of modified chain aliphatic polyamine manufactured by Dainippon Ink and Chemicals, Inc. (the glass transition point of the cured product of the mixture was 40 ° C. by DSC measurement) was used, and the adhesive layer (B A hollow fiber membrane module 6 was obtained in the same manner as in Example 2 except that () was not prepared.

(Evaluation of Membrane Module) While hot water of 60 ° C. is caused to flow inside the hollow fiber of the obtained hollow fiber membrane module 6, pressurization of 0 kgf / cm ² · G and 5 kgf / cm ² G is alternately repeated. When the test was conducted, water leakage occurred 5,000 times. When observing both ends of the hollow fiber membrane module, a dent in the adhesive portion toward the inside of the module was observed.

[Comparative Example 3] A hollow fiber membrane module 7 was obtained in the same manner as in Example 1 except that the order of the adhesive layer (A) and the adhesive layer (B) was reversed.

(Evaluation of Membrane Module) While hot water of 60 ° C. is caused to flow inside the hollow fiber of the obtained hollow fiber membrane module 7, pressurization of 0 kgf / cm ² · G and 5 kgf / cm ² G is alternately repeated. When the test was conducted, water leakage occurred 7,000 times. When observing both ends of the hollow fiber membrane module, a dent in the adhesive portion toward the inside of the module was observed.

[0045]

EFFECT OF THE INVENTION A membrane that can be constantly used at a high temperature of about 60 ° C. or higher and does not cause damage to the hollow fiber membrane when sealing the case and the end of the hollow fiber membrane or when pressure is applied to the hollow fiber membrane module. Provide the module. The present invention is expected to have an effect of expanding its application range to a field in which a hollow fiber separation membrane has not been put to practical use in the past and is always used at high temperature.

Claims (6)

[Claims] 1. A membrane module having a structure in which a hollow fiber membrane is arranged in a case, and the case and the end of the hollow fiber membrane are sealed with an adhesive, wherein the adhesive portion is the length of the hollow fiber. The heat-resistant adhesive layer (A) having a glass transition point of 50 ° C. or higher from the end side in the direction, and then the adhesive layer (B) having a lower glass transition point in that order. Characteristic membrane module. 2. The membrane module according to claim 1, wherein each of the adhesive layer (A) and the adhesive layer (B) is an adhesive layer composed of an epoxy main agent and a curing agent. 3. The membrane module according to claim 2, wherein the curing agent for the adhesive layer (B) is a linear aliphatic polyamine and / or a modified product thereof. 4. The curing agent for the adhesive layer (A) contains at least one curing agent selected from the group consisting of cycloaliphatic polyamines, aromatic polyamines, imidazoles and modified products thereof. Item 2. The membrane module according to item 2. 5. The glass transition point of the adhesive layer (A) is 60-9.
The temperature is 0 ° C. and the glass transition point of the adhesive layer (B) is 20.
The membrane module according to claim 2, 3 or 4, which has a temperature of -50C. 6. The thickness ratio (A) / (B) of the adhesive layer (A) and the adhesive layer (B) is 80/20 to 99/1, and any one of claims 1-5. Membrane module described in 1.