JPH05184882A - Method for manufacturing hollow fiber membrane module - Google Patents

Abstract

PURPOSE:To prevent the peeling of an adhesive from an outer cylinder and to obtain heat resistance, solvent resistance and enough mechanical strength of the fixed adhesive. CONSTITUTION:An epoxy resin with xylylene diamine or bis(aminomethyl) cyclohexane as a hardening agent is used as the material of the outer cylinder and the component of the adhesive. The outer cylinder is filled with hollow fiber membrane bundles and the end parts are adhered and fixed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a hollow fiber membrane module used for separating a liquid or a gas.

[0002]

2. Description of the Related Art In recent years, ultrapure water of the electronics industry,
Alternatively, membranes such as ultrafiltration in sterile water production, reverse osmosis in desalination of seawater, hemodialysis in artificial kidneys, pervaporation in separation of water from alcohol aqueous solution (hereinafter referred to as pervaporation) The separation technology used is developing remarkably.

Separation membranes used in such separation techniques are roughly classified into two types, flat membranes and hollow fiber membranes, depending on their forms. Among them, a separation device containing a hollow fiber membrane (hereinafter referred to as a hollow fiber membrane module) has an advantage that it can be made compact as compared with a flat membrane device, and is widely used in various fields. .. Also, various shapes of hollow fiber membrane modules are known, but most commonly, a bundle composed of a large number of hollow fiber membranes (hereinafter simply referred to as a hollow fiber membrane bundle) is introduced into the outer cylinder. Then, after fixing both ends with an adhesive, the both ends or one end is cut and the hollow fiber membrane is opened to form a module.

[0004]

The hollow fiber membrane module in which the hollow fiber membrane is introduced into the outer cylinder as described above and fixed at both ends with the adhesive, the injected adhesive shrinks when it is thermoset. However, there was a gap between the outer cylinder and the outer cylinder, and there was a problem that sealing could not be performed well.

Therefore, various measures have been taken, and most of them are attempts to reduce the internal stress when the adhesive is cured.

For example, a method of fixing the hollow fiber membrane bundle with an adhesive in advance, then introducing the bundle into the outer cylinder, and fixing with the adhesive.

A method of injecting an adhesive and fixing the hollow fiber membrane in several steps.

A method of mixing a filler (silica, thermoplastic resin, etc.) into the adhesive.

Etc.

However, the above method has the following problems. That is, and, the operation is very complicated, and the outer cylinder and the adhesive may still be peeled off. May cause separation of the filler in the adhesive.

The present invention provides a method for manufacturing a hollow fiber membrane module in which the outer cylinder and the adhesive are not separated from each other.

[0012]

[Means for Solving the Problems] The inventors of the present invention have conducted extensive research to solve the above technical problems. As a result, an outer cylinder was made in advance with a cured product of an adhesive, and an adhesive of the same composition was injected to fix the hollow fiber membrane there, and by selecting a curing agent for the adhesive,
The present invention has been completed based on the finding that a hollow fiber membrane module can be obtained in which the outer cylinder and the adhesive are not peeled off and the fixed adhesive has heat resistance, solvent resistance, and sufficient mechanical strength. That is, according to the present invention, the outer cylinder is filled with a bundle of hollow fiber membranes, and the ends of the hollow fiber membranes are bonded to each other and the hollow fiber membrane bundles and the outer cylinder are bonded with an adhesive. When fixing and sealing, a hollow fiber membrane module characterized by using an epoxy resin having xylylenediamine or bis (aminomethyl) cyclohexane as a curing agent as the material of the outer cylinder and the composition component of the adhesive. Is a manufacturing method.

The manufacturing method of the present invention is conventionally known in which a hollow fiber membrane bundle is inserted into an outer cylinder, and the hollow fiber membranes are generally bonded and fixed at both ends thereof with a casting synthetic resin. The hollow fiber membrane module can be applied to any mode without particular limitation.

The shape of the outer cylinder used in the present invention is not limited in any way, but the material of at least the portion at which the hollow fiber membrane bundle is adhered and fixed at the end is xylylenediamine or bis (aminomethyl) cyclohexane as a curing agent. It is extremely important that the specified epoxy resin is used.

The physical properties of the cylindrical cured product made of the above-mentioned epoxy resin which constitutes the outer cylinder of the present invention are limited. That is, it must have the mechanical strength required when the adhesive is injected later. On the other hand, depending on the adhesive, if the curing reaction proceeds too much, sufficient mechanical strength can be obtained, but the compatibility with the adhesive injected afterwards becomes poor,
Peeling may occur. Therefore, when, for example, m-phenylenediamine or 4,4′-diaminodiphenylmethane is used as a curing agent for an epoxy resin whose cured product is expected to have heat resistance and solvent resistance, mechanical strength at a curing temperature of 80 ° C. Since it is insufficient, it cannot be cut or adhesive cannot be injected later. Also, the curing temperature is 120 ° C.
However, sufficient mechanical strength can be obtained, but when the adhesive is injected afterwards and cured, shrinkage occurs, and sufficient sealing cannot be achieved. Further, when using, for example, polyamidoamine as an epoxy resin curing agent that is considered to have a small shrinkage at the time of curing, only by curing at room temperature,
The tubular cured product has sufficient mechanical strength and does not peel off even if an adhesive is injected later. However, the fixed part of the resulting hollow fiber membrane module does not have heat resistance and solvent resistance, and cannot be used in applications where severe conditions such as pervaporation are required.

Whether or not the above-mentioned tubular cured product and the adhesive injected afterward peels off can be estimated by the glass transition temperature (Tg) of the tubular cured product. The term "Tg" used herein means a differential scanning calorimetry (DS) of a cylindrical cured product.
It is a value measured by increasing the temperature at 5 ° C./min according to C). Tg of the tubular cured product used in the present invention is
50-130 degreeC, Preferably it is 65-120 degreeC.
When Tg is low, the mechanical strength of the cured product is often insufficient, and the heat resistance and solvent resistance of the fixed part of the finished hollow fiber membrane module are poor. On the other hand, if Tg is too high, the adhesive force with the adhesive to be injected later is reduced and peeling easily occurs.

The xylylenediamine used in the present invention includes three kinds of o-form, m-form and p-form, and among them, m
-Easy to use as the body is cheap and easy to obtain. Further, bis (aminomethyl) cyclohexane includes 1,2-form, 1,3-form, and 1,4-form depending on the position of the aminomethyl group, and each has cis-trans isomers. Since the 1,3-isomer cis-trans mixture is inexpensive and easily available, it is easy to use. The base material of the epoxy resin used in the present invention is not particularly limited, and examples include bisphenol A type.

[0018]

[Chemical 1]

(N = 0 to 2) 1 phenol novolac type

[0020]

[Chemical 2]

(N = 0 to 2) 1 diglycidyl amine type

[0022]

[Chemical 3]

Known compounds such as (R = alkyl group or aromatic ring) are used.

When manufacturing such a tubular cured product, the mixing ratio of the main component of the epoxy resin and the curing agent is such that the ratio of glycidyl group of the main component of the epoxy resin to the amino group of the curing agent is glycidyl group / amino group. 0.2-5.0, preferably 0.
It is used so that it becomes 4 to 3. It is desirable that the epoxy resin main component and the curing agent be mixed and then degassed before use. The curing conditions for the production of the tubular cured product are xylylenediamine and bis (aminomethyl) cyclohexane.
After mixing with the main component of the epoxy resin and leaving it at room temperature for 30 minutes to 24 hours, it is kept warm at 40 to 120 ° C. for 1 to 24 hours. In particular, after leaving at room temperature for 3 to 24 hours, 50
It is preferable to keep the temperature at -80 ° C for 1 hour to 24 hours.
At the time of curing, it may be left to stand at room temperature and heated immediately. However, note that when the amount of the adhesive is large, the curing reaction may proceed too much when heated and the internal temperature of the adhesive may rise above the set temperature. The method for producing the tubular cured product is not particularly limited. Generally, a method of manufacturing by cutting a cured product of an adhesive,
A method of making a cylindrical mold, injecting an adhesive, curing the adhesive, and then removing the mold can be used.

In the present invention, the same xylylenediamine or bis which was used when producing the above-mentioned tubular cured product of the outer cylinder was used as an adhesive for adhering and fixing the ends of the hollow fiber membrane bundle in the outer cylinder. It is essential to use a composition of epoxy resin with (aminomethyl) cyclohexane as the curing agent.
That is, when an adhesive having a composition different from that of the outer cylinder is used, the adhesiveness is deteriorated and peeling often occurs. The curing conditions for injecting and curing the adhesive in such an outer cylinder must be the same as or more strict than the curing conditions used for producing the cylindrical cured product of the outer cylinder. Specifically, after keeping the temperature at 50 to 80 ° C. for 1 to 24 hours, further at 120 to 150 ° C. for 1 to 2
Post-curing for 4 hours is desirable. The hollow fiber membrane used in the present invention is not particularly limited in its material and the like. For example, polyethylene, polypropylene, polyolefin such as polyacrylonitrile, cellulose, cellulose acetate,
Materials such as biopolymers such as chitosan and engineering plastics such as polysulfone, polyether sulfone, polyimide, and polyetherimide can be used. In addition, there are no restrictions on the application of the hollow fiber membrane,
For example, it can be used for ultrafiltration, microfiltration, pervaporation and the like.

[0026]

[Effects] According to the present invention, a tubular cured product of an outer cylinder is manufactured in advance with a specified composition, and the end portions of the hollow fiber membrane bundle are adhered and fixed with an adhesive of the same composition, thereby peeling. It is possible to obtain a hollow fiber membrane module that has less heat resistance and solvent resistance and has sufficient mechanical strength in the fixed portion. This gives a hollow fiber membrane module that can be used even under severe conditions such as pervaporation.

[0027]

EXAMPLES The present invention will now be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 A mixture of 100 parts by weight of a phenol novolac type epoxy resin Epicoat 152 (produced by Yuka Shell Co., Ltd.) and 20 parts by weight of metaxylylenediamine was poured into a mold and left at room temperature (25 ° C.) for 24 hours. Then, it was further cured at 80 ° C. for 3 hours to produce a cylindrical cured product having a length of 52 cm, an outer diameter of 3.2 cm and an inner diameter of 2.8 cm. Further, one hole having a diameter of 1 cm was opened in the central portion of the cylindrical cured product so that the nozzle could be attached later, and the screw was cut. Tg of this cylindrical cured product
Was 95 ° C.

Next, 200 quaternized polyetherimide hollow fiber membranes formed by the method disclosed in JP-A-2-35923 (length 570 mm, outer diameter 0.9 mm, inner diameter 0.6 mm). After sealing both ends of the hollow fiber membrane bundle at both ends,
It was set on a centrifugal casting stand and centrifugal casting was performed with an adhesive. The adhesive had the same composition as when the cylindrical cured product was manufactured. The curing conditions were such that the temperature was kept at 80 ° C. for 3 hours, and then post-cured at 120 ° C. for 3 hours. After curing, the module was removed from the centrifugal casting table, both ends were cut, and the hollow fiber membrane was opened to obtain a module.

The module was assembled with a pervaporation separation device, and a solution of IPA: H ₂ O = 85: 15 (wt%) was supplied to carry out pervaporation.
The module was operated for 30 days, but no abnormality was found in the module.

Example 2 Epoxy resin Epicoat 15 identical to that used in Example 1
2 A mixture of 100 parts by weight and 20.5 parts by weight of 1,3-bis (aminomethyl) cyclohexane (a mixture of cis and trans) was left at room temperature (25 ° C) for 24 hours and then kept at 80 ° C for 24 hours to cure. I made things. By cutting the cured product, a cylindrical cured product having a length of 4 cm, an outer diameter of 3.2 cm and an inner diameter of 2.8 cm was produced. The Tg of this cylindrical cured product was 102 ° C.

Next, the same hollow fiber membrane bundle as in Example 1, the above-mentioned cylindrical cured product, and a stainless steel spacer (length 44 cm, circular portions at both ends, outer diameter 3.2 cm, inner diameter 2.8 c).
m) was set on a centrifugal casting stand, and centrifugal casting was performed with an adhesive. The adhesive had the same composition as when the cylindrical cured product was manufactured. The curing conditions were such that the temperature was kept at 80 ° C. for 3 hours, and then post-cured at 120 ° C. for 3 hours. After curing
The module was removed from the centrifugal casting stand, both ends were cut, and the hollow fiber membrane was opened to obtain a module.

The module was assembled in a pervaporation separation apparatus, IPA: H ₂ O = 85: 15 (wt%) liquid was supplied, and pervaporation was performed.
As a result, the module was operated for 30 days, but no abnormality was found in the module.

Example 3 The same procedure as in Example 2 except that a mixture of 100 parts by weight of bisphenol A type epoxy resin Epicoat 828 (manufactured by Yuka Shell Co.) and 18 parts by weight of metaxylylenediamine was used as the adhesive only. Was done. The Tg of the produced cylindrical cured product was 92 ° C.

Using the obtained hollow fiber membrane module separator, pervaporation was carried out for 30 days in the same manner as in Example 2, but no abnormality was found in the module.

Example 4 Same as Example 1 except that a mixture of 100 parts by weight of epoxy resin Epicoat 828 only for adhesive and 19 parts by weight of 1,3-bis (aminomethyl) cyclohexane (mixture of cis and trans) was used. The operation was performed. The Tg of the produced cylindrical cured product was 92 ° C.

Using the obtained hollow fiber membrane module separator, pervaporation was carried out for 30 days in the same manner as in Example 1, but no abnormality was found in the module.

Comparative Example 1 The same operation as in Example 2 was carried out except that a mixture of 100 parts by weight of epoxy resin Epicoat 152 and 36 parts by weight of a curing agent ED-002 (polyamide amine, manufactured by Konishi Co.) was used as an adhesive only. It was Tg of manufactured cylindrical cured product
Was 62 ° C.

Further, pervaporation was carried out by the obtained hollow fiber membrane module separation device in the same manner as in Example 2, and on the 20th day, the fixed portion of the module swelled and cracked, and the operation was possible. lost.

Comparative Example 2 A mixture of 100 parts by weight of Epicoat 152 alone, 22 parts by weight of curing agent Epicure Z (a mixture of metaphenylenediamine and diaminodiphenylmethane, manufactured by Yuka Shell Co., Ltd.) at room temperature was prepared in the same manner as in Example 2. After being left at (25 ° C.) for 24 hours, it was kept at 80 ° C. for 24 hours to prepare a cured product. However, the cured product is
Since it was not sufficiently cured, it was further cured at 150 ° C for 3 hours and then cut to a length of 4 cm and an outer diameter of 3.2 cm.
And a cylindrical cured product having an inner diameter of 2.8 cm was produced. The Tg of the cylindrical cured product was 145 ° C.

Next, as in Example 2, centrifugal casting was performed with an adhesive. However, the curing conditions are 80 ° C 3
After incubating for 100 hours, 100 ℃ for 3 hours and 150 ℃ for 5 hours
It was time.

When observed after curing, the cylindrical cured product and a part of the adhesive injected at the time of centrifugal casting were separated,
It could not be used as a hollow fiber membrane module.

Comparative Example 3 A hollow fiber was prepared in the same manner as in Example 2 except that a mixture of 100 parts by weight of Epicoat 828 and 18 parts by weight of metaxylylenediamine was used as the only adhesive to be subsequently injected into the cylindrical cured product. A membrane module was manufactured. Furthermore, although pervaporation was performed under the same conditions as in Example 2, on the 15th day, a crack was formed between the cylindrical cured product and the adhesive injected afterwards, and operation could not be performed.

Claims (1)

[Claims] 1. An outer cylinder is filled with a bundle of hollow fiber membranes, and the ends of the bundle are bonded to each other and between the hollow fiber membrane bundles and the outer cylinder with an adhesive. When fixing and sealing, a hollow fiber membrane module characterized by using an epoxy resin having xylylenediamine or bis (aminomethyl) cyclohexane as a curing agent as the material of the outer cylinder and the composition component of the adhesive. Manufacturing method.