JPH0361486B2 - - Google Patents
Info
- Publication number
- JPH0361486B2 JPH0361486B2 JP58131047A JP13104783A JPH0361486B2 JP H0361486 B2 JPH0361486 B2 JP H0361486B2 JP 58131047 A JP58131047 A JP 58131047A JP 13104783 A JP13104783 A JP 13104783A JP H0361486 B2 JPH0361486 B2 JP H0361486B2
- Authority
- JP
- Japan
- Prior art keywords
- membrane
- polysulfone
- skin layer
- sulfolane
- parts
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000012528 membrane Substances 0.000 claims description 29
- 229920002492 poly(sulfone) Polymers 0.000 claims description 22
- RUOJZAUFBMNUDX-UHFFFAOYSA-N propylene carbonate Chemical compound CC1COC(=O)O1 RUOJZAUFBMNUDX-UHFFFAOYSA-N 0.000 claims description 11
- HXJUTPCZVOIRIF-UHFFFAOYSA-N sulfolane Chemical compound O=S1(=O)CCCC1 HXJUTPCZVOIRIF-UHFFFAOYSA-N 0.000 claims description 11
- 230000015572 biosynthetic process Effects 0.000 claims description 9
- 238000005345 coagulation Methods 0.000 claims description 9
- 230000015271 coagulation Effects 0.000 claims description 9
- 239000007788 liquid Substances 0.000 claims description 7
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 239000011259 mixed solution Substances 0.000 claims description 3
- 239000000243 solution Substances 0.000 description 14
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 12
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 8
- 239000011148 porous material Substances 0.000 description 8
- 239000002904 solvent Substances 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 5
- 230000001112 coagulating effect Effects 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 239000011347 resin Substances 0.000 description 5
- 229920005989 resin Polymers 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- 239000003795 chemical substances by application Substances 0.000 description 4
- 238000000926 separation method Methods 0.000 description 4
- 229910001220 stainless steel Inorganic materials 0.000 description 4
- 239000010935 stainless steel Substances 0.000 description 4
- 230000008961 swelling Effects 0.000 description 4
- 229920002307 Dextran Polymers 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 238000000605 extraction Methods 0.000 description 3
- 230000005484 gravity Effects 0.000 description 3
- 239000012510 hollow fiber Substances 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 150000002605 large molecules Chemical class 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 229920002301 cellulose acetate Polymers 0.000 description 1
- 229920006351 engineering plastic Polymers 0.000 description 1
- 238000005194 fractionation Methods 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 229920001223 polyethylene glycol Polymers 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 102000004169 proteins and genes Human genes 0.000 description 1
- 108090000623 proteins and genes Proteins 0.000 description 1
- 230000001954 sterilising effect Effects 0.000 description 1
- 238000004659 sterilization and disinfection Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/06—Organic material
- B01D71/66—Polymers having sulfur in the main chain, with or without nitrogen, oxygen or carbon only
- B01D71/68—Polysulfones; Polyethersulfones
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0002—Organic membrane manufacture
- B01D67/0009—Organic membrane manufacture by phase separation, sol-gel transition, evaporation or solvent quenching
- B01D67/0016—Coagulation
- B01D67/00165—Composition of the coagulation baths
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2323/00—Details relating to membrane preparation
- B01D2323/12—Specific ratios of components used
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2323/00—Details relating to membrane preparation
- B01D2323/15—Use of additives
- B01D2323/16—Swelling agents
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Dispersion Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Description
【発明の詳細な説明】
本発明は、多孔性ポリサルホン膜の湿式製膜に
関するものであり、その目的とするところは孔径
が0.05〜10μ、好ましくは0.1〜1.0μの孔を有し、
例えば蛋白質等比較的大きな分子量のものを過
する膜を製造する方法を提供するにある。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to wet film forming of a porous polysulfone membrane, and its purpose is to have pores with a pore size of 0.05 to 10μ, preferably 0.1 to 1.0μ,
The object of the present invention is to provide a method for producing a membrane that can pass through relatively large molecular weight substances such as proteins.
ポリサルホンはエンジニアリングプラスチツク
として開発されたものであり、熱および機械的性
質が優れており、耐酸、耐アルカリ性等化学的性
質にもすぐれた樹脂である。 Polysulfone was developed as an engineering plastic, and is a resin with excellent thermal and mechanical properties, as well as excellent chemical properties such as acid resistance and alkali resistance.
膜素材としても蒸気減菌処理が可能であり、食
品医療用としての期待が持たれている。 It can also be used as a membrane material through steam sterilization, and is expected to be used for food and medical purposes.
しかしセルロースアセテート等に比較し、分子
間凝集力が強すぎ、孔径を製御するのが困難であ
る。特に本発明で目的としている様な表面に
0.05μ以上の孔を有する、いわゆるスキン層で被
覆されていない多孔膜について従来より知られて
いる製造方法はいくつかの問題点を有している。 However, compared to cellulose acetate and the like, the intermolecular cohesive force is too strong, making it difficult to control the pore size. Especially on surfaces such as those targeted by the present invention.
Conventionally known manufacturing methods for porous membranes having pores of 0.05 μm or more and not covered with a so-called skin layer have several problems.
例えば抽出法が知られている。すなわち抽出可
能な物質をレジンを溶液あるいはレジンに混ぜ製
膜後に抽出するもので、例えばポリサルホンにつ
いては抽出物としてポリエチレングリコールが特
開昭57−35906号公報および特開昭55−106243号
公報で提唱されている。しかし抽出を完全に行な
うには多大の労力と時間を要し、また条件によつ
ては生成した微細孔が貫通せず抽出不充分となる
か、あるいは膜に独立気泡が残り過抵抗が大き
くなるという問題を有している。 For example, extraction methods are known. In other words, extractable substances are mixed with a resin solution or resin and extracted after film formation.For example, polysulfone is extracted using polyethylene glycol as an extractant in JP-A-57-35906 and JP-A-55-106243. has been done. However, it takes a lot of effort and time to perform complete extraction, and depending on the conditions, the generated micropores may not penetrate, resulting in insufficient extraction, or closed cells may remain in the membrane, resulting in increased overresistance. There is a problem.
さらに湿式製膜において凝固液中に良溶媒を添
加することも知られている。例えばポリサルホン
について特開昭56−152704号公報をあげることが
出来る。しかしこの方法では実質スキン層のない
膜を得るには凝固液中に良溶媒が少くとも70％以
上含まれている必要がある。この場合凝固が非常
に遅くなり、例えば内外両表面ともにスキン層で
被覆されていない中空糸を得るのは困難である。 Furthermore, it is also known to add a good solvent to the coagulation liquid in wet film formation. For example, JP-A-56-152704 can be mentioned regarding polysulfone. However, with this method, in order to obtain a film with virtually no skin layer, it is necessary that the coagulation liquid contains at least 70% or more of a good solvent. In this case, coagulation becomes very slow and it is difficult to obtain hollow fibers which are not coated with skin layers on both the inner and outer surfaces, for example.
本発明は、従来困難であつたスキン層で被覆さ
れていない多孔性ポリサルホン膜の製造に関し研
究の結果、良溶媒でなく適当な貧溶媒を用いても
スキン層の被覆を防止し得るとの知見を得、さら
にこの知見に基づき鋭意検討を進めた結果、本発
明を完成するに至つたものである。 The present invention is based on research into the production of porous polysulfone membranes that are not coated with a skin layer, which has been difficult in the past, and has revealed that coating with the skin layer can be prevented even when a suitable poor solvent is used instead of a good solvent. As a result of further intensive studies based on this knowledge, we have completed the present invention.
本発明は、湿式製膜により多孔性膜を製造する
にあたり、凝固液としてプロピレンカーボネート
及び／又はスルホランが20〜90重量％含まれる混
合液を用いることを特徴とする多孔性ポリサルホ
ン膜の製造方法である。 The present invention is a method for producing a porous polysulfone membrane, which is characterized in that a mixed solution containing 20 to 90% by weight of propylene carbonate and/or sulfolane is used as a coagulating liquid when producing a porous membrane by wet membrane formation. be.
本発明で用いられるポリサルホンは あるいは あるいは あるいは の繰り返し単位をもつものである。 The polysulfone used in the present invention is or or or It has a repeating unit of.
ポリサルホン溶液組成はとくに限定されない
が、従来の湿式製膜と同様良溶媒だけでなく膨潤
剤を加えるのが良い。膨潤剤としては、例えばア
ルコール類をあげる事が出来る。メタノール、エ
タノールも良好な効果を示すが、作業性の点から
エチレングリコール等沸点の高いものを用いても
よい。 Although the composition of the polysulfone solution is not particularly limited, it is preferable to add not only a good solvent but also a swelling agent as in conventional wet film formation. Examples of swelling agents include alcohols. Methanol and ethanol also show good effects, but from the point of view of workability, substances with a high boiling point such as ethylene glycol may also be used.
発明者は既にエチレンカーボネート、プロピレ
ンカーボネート、スルホランがポリサルホンの良
好な膨潤剤である事を見い出しているが、それぞ
れ用いる事も出来る。本発明に於いては凝固液中
にプロピレンカーボネート（比重約1.21）又はス
ルホラン（比重約1.26）が存在する事から、製膜
条件によつてはポリサルホン溶液側の比重を高め
ておく必要のある場合が出るので、この意味から
も好適である。 The inventor has already found that ethylene carbonate, propylene carbonate, and sulfolane are good swelling agents for polysulfone, but each can also be used. In the present invention, since propylene carbonate (specific gravity approximately 1.21) or sulfolane (specific gravity approximately 1.26) is present in the coagulation solution, it may be necessary to increase the specific gravity of the polysulfone solution depending on the film forming conditions. , so it is suitable from this point of view as well.
凝固液組成は、プロピレンカーボネート又はス
ルホランが20〜90重量％含まれる事の他は、ポリ
サルホンに対し凝固性を示し、かつプロピレンカ
ーボネート、スルホランを分解せず、製膜時の温
度で溶液状態となるものであれば、時に限定され
ない。 The coagulating liquid composition contains 20 to 90% by weight of propylene carbonate or sulfolane, and has coagulability with polysulfone, does not decompose propylene carbonate or sulfolane, and becomes a solution at the temperature during film formation. As long as it is something, it is not limited to time.
プロピレンカーボネート又はスルホランと混合
するものとしては、水、アルコール等のポリサル
ホンの膨潤剤、あるいはＮ−メチル２ピロリドン
を様なポリサルホンの良溶媒、およびこれらの混
合溶液が例としてあげられる。 Examples of substances to be mixed with propylene carbonate or sulfolane include swelling agents for polysulfone such as water and alcohol, good solvents for polysulfone such as N-methyl 2-pyrrolidone, and mixed solutions thereof.
プロピレンカーボネート又はスルホランの量
は、相手側のポリサルホン溶液組成、温度および
凝固液温度によつて20〜90重量％と範囲で変化し
得る。使用する量が20重量％を下回ると、スキン
層形成防止の効果が減少し、例えば透水量は1000
／m2・hr・atmのオーダーまで低下する。90重
量％を上回ると凝固が遅くなり製膜時の作業性が
悪くなる。 The amount of propylene carbonate or sulfolane can vary from 20 to 90% by weight depending on the partner polysulfone solution composition, temperature and coagulation liquid temperature. If the amount used is less than 20% by weight, the effect of preventing skin layer formation will decrease, for example, the water permeability will be 1000%.
/ m2・hr・atm. If it exceeds 90% by weight, coagulation will be slow and workability during film formation will be poor.
膜形状は平板膜、中空糸等通常の湿式製膜で作
られるものはいずれも可能である。中空糸の場合
環状ノズルの内外の凝固液が異なつてもよい。 The membrane shape can be any shape made by normal wet membrane formation, such as a flat plate membrane or hollow fiber. In the case of hollow fibers, the coagulating liquids inside and outside the annular nozzle may be different.
本発明によつて煩雑な工程を必要とせず、また
膜形状に対する制限を受ける事なく、スキン層で
被覆されていない比較的高分子量の化合物を過
するポリサルホン製分離膜を容易に製造する事が
出来る。 According to the present invention, it is possible to easily produce a polysulfone separation membrane that passes relatively high molecular weight compounds that are not covered with a skin layer, without requiring complicated processes or being subject to restrictions on membrane shape. I can do it.
ここに言うスキン層とは、膜表面に存在する被
膜の事で緻密層とも呼ばれている。現在のところ
電子顕微鏡によつても実質的にスキン層上の孔の
孔径の測定は困難である。R.O.膜あるいは低分
子分画用のU.F.膜には必要であるが、スキン層
が膜表面を完全に覆うと、高分子量化合物は通過
できない。特に限定するものではないが、スキン
層で被覆されていない目安としてブルーデキスト
ラン（分子量約200万）が通過する事が利用でき
る。 The skin layer referred to here refers to a film that exists on the surface of a membrane, and is also called a dense layer. At present, it is practically difficult to measure the pore diameter of the pores on the skin layer even with an electron microscope. This is necessary for RO membranes or UF membranes for low molecular fractionation, but when the skin layer completely covers the membrane surface, high molecular weight compounds cannot pass through. Although not particularly limited, the fact that blue dextran (molecular weight approximately 2 million) passes can be used as an indicator of not being covered with a skin layer.
プロピレンカーボネートやスルホランは、ポリ
サルホンに対し非溶媒であるが、アルコールより
は親和性をもつ。こと事が従来提唱されていた良
溶媒あるいはアルコール等の凝固液への添加に較
べ、スキン層の被覆防止と製膜作業性とのバラン
スがとれ、好結果を与えたものと考えられる。 Propylene carbonate and sulfolane are non-solvents for polysulfone, but they have a better affinity than alcohol. This is considered to be the reason why the method achieved a better balance between prevention of skin layer coating and film forming workability than the conventionally proposed addition of a good solvent or alcohol to the coagulating solution.
以下実施例により更に詳細に説明する。 This will be explained in more detail with reference to Examples below.
実施例 １
の繰り返し単位からなるポリサルホン樹脂（ICI
社製、商品名VICTREX300P）12重量部（以下
重量部で示す）を、Ｎ−メチル２ピロリドン30.4
部、プロピレンカーボネート45.6部、エチレング
リコール12部よりなる混合溶液に加熱溶解し、製
膜用溶液を得た。Example 1 Polysulfone resin (ICI
12 parts by weight (hereinafter referred to as parts by weight) of VICTREX300P manufactured by
1 part, 45.6 parts of propylene carbonate, and 12 parts of ethylene glycol to obtain a film-forming solution.
脱泡後、製膜溶液を50℃とし、同じく50℃のス
テンレスベルト上に流延し、ただちにＮ−メチル
２ピロリドン28.6部、プロピレンカーボネート
42.8部、水28.6部からなる50℃に保つた凝固液に
浸漬、凝固させ平板状のポリサルホン製分離膜を
得た。 After defoaming, the membrane forming solution was heated to 50°C, cast onto a stainless steel belt also at 50°C, and immediately mixed with 28.6 parts of N-methyl 2-pyrrolidone and propylene carbonate.
A flat polysulfone separation membrane was obtained by immersion and coagulation in a coagulation solution containing 42.8 parts of water and 28.6 parts of water kept at 50°C.
得られた膜はブルーデキストランが通過し、表
面を電子顕微鏡で観察したところ0.1〜0.2μの孔
が確認出来た。 Blue dextran passed through the obtained membrane, and when the surface was observed with an electron microscope, pores of 0.1 to 0.2 μm were confirmed.
実施例 ２
実施例１で用いたと同じポリサルホン樹脂12
部、Ｎ−メチル２ピロリドン8.2部、スルホラン
73.8部、エチレングリコール６部からなる製膜用
溶液を40℃に保ち、実施例１と同様に40℃にした
ステンレスベルト上に流延した。ただちにＮ−メ
チル２ピロリドン22部、スルホラン33部、水44部
からなる40℃に保つた凝固液に浸漬、凝固させ平
板状のポリサルホン製分離膜を得た。Example 2 The same polysulfone resin 12 used in Example 1
part, N-methyl 2-pyrrolidone 8.2 parts, sulfolane
A film forming solution consisting of 73.8 parts of ethylene glycol and 6 parts of ethylene glycol was maintained at 40°C and cast onto a stainless steel belt heated to 40°C in the same manner as in Example 1. Immediately, the mixture was immersed in a coagulating solution containing 22 parts of N-methyl 2-pyrrolidone, 33 parts of sulfolane, and 44 parts of water kept at 40 DEG C. to coagulate it to obtain a flat polysulfone separation membrane.
得られた膜はブルーデキストランが通過し、表
面を電子顕微鏡で観察したところ0.1〜0.2μの孔
が確認出来た。 Blue dextran passed through the obtained membrane, and when the surface was observed with an electron microscope, pores of 0.1 to 0.2 μm were confirmed.
比較例 １
実施例１で用いたと同じ製膜溶液を50℃に保
ち、同じく50℃に保つたステンレスベルト上に流
延し、ただちに50℃にした水に浸漬、凝固させ平
板状のポリサルホン製分離膜を得た。Comparative Example 1 The same membrane-forming solution used in Example 1 was kept at 50°C, cast onto a stainless steel belt also kept at 50°C, and immediately immersed in water heated to 50°C to solidify to form a flat polysulfone separation material. A membrane was obtained.
得られた膜を顕微鏡で観察したところ、表面が
スキン層で覆れている事が確認できた。 When the obtained film was observed under a microscope, it was confirmed that the surface was covered with a skin layer.
比較例 ２
実施例２で用いたと同じ製膜溶液を40℃にし、
同じく40℃に保つたステンレスベルト上に流延
し、ただちに40℃にした水に浸漬、凝固させ平板
膜を得た。Comparative Example 2 The same membrane forming solution used in Example 2 was heated to 40°C,
The mixture was cast onto a stainless steel belt kept at 40°C, and immediately immersed in water heated to 40°C to solidify to obtain a flat membrane.
得られた膜は、比較例１と同様に観察した結
果、スキン層で覆れている事が確認できた。 The obtained film was observed in the same manner as in Comparative Example 1, and it was confirmed that it was covered with a skin layer.
Claims (1)
り、凝固液としてプロピレンカーボネート及び／
又はスルホランが20〜90重量％含まれる混合液を
用いることを特徴とする多孔性ポリサルホン膜の
製造方法。1 When producing a porous membrane by wet membrane formation, propylene carbonate and/or coagulation liquid are used.
Or, a method for producing a porous polysulfone membrane, characterized by using a mixed solution containing 20 to 90% by weight of sulfolane.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58131047A JPS6025511A (en) | 1983-07-20 | 1983-07-20 | Preparation of porous polysulfone membrane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58131047A JPS6025511A (en) | 1983-07-20 | 1983-07-20 | Preparation of porous polysulfone membrane |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6025511A JPS6025511A (en) | 1985-02-08 |
| JPH0361486B2 true JPH0361486B2 (en) | 1991-09-20 |
Family
ID=15048771
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58131047A Granted JPS6025511A (en) | 1983-07-20 | 1983-07-20 | Preparation of porous polysulfone membrane |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6025511A (en) |
-
1983
- 1983-07-20 JP JP58131047A patent/JPS6025511A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6025511A (en) | 1985-02-08 |
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