JPS634862B2 - - Google Patents
Info
- Publication number
- JPS634862B2 JPS634862B2 JP58081506A JP8150683A JPS634862B2 JP S634862 B2 JPS634862 B2 JP S634862B2 JP 58081506 A JP58081506 A JP 58081506A JP 8150683 A JP8150683 A JP 8150683A JP S634862 B2 JPS634862 B2 JP S634862B2
- Authority
- JP
- Japan
- Prior art keywords
- oxidizing agent
- membrane
- polymer
- solution
- oxidizing
- 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 28
- 239000007800 oxidant agent Substances 0.000 claims description 26
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 claims description 15
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 12
- 229920005597 polymer membrane Polymers 0.000 claims description 11
- 239000000463 material Substances 0.000 claims description 7
- 238000000034 method Methods 0.000 claims description 7
- 229920000642 polymer Polymers 0.000 claims description 7
- 239000003960 organic solvent Substances 0.000 claims description 5
- 230000001590 oxidative effect Effects 0.000 claims description 5
- 238000005266 casting Methods 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 229920006254 polymer film Polymers 0.000 claims 1
- 239000000243 solution Substances 0.000 description 17
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 10
- 238000000926 separation method Methods 0.000 description 9
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 5
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 5
- 235000019253 formic acid Nutrition 0.000 description 5
- 230000003647 oxidation Effects 0.000 description 5
- 238000007254 oxidation reaction Methods 0.000 description 5
- 239000012286 potassium permanganate Substances 0.000 description 4
- 229920002301 cellulose acetate Polymers 0.000 description 3
- 229920002125 Sokalan® Polymers 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 239000007795 chemical reaction product Substances 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- AMWRITDGCCNYAT-UHFFFAOYSA-L hydroxy(oxo)manganese;manganese Chemical compound [Mn].O[Mn]=O.O[Mn]=O AMWRITDGCCNYAT-UHFFFAOYSA-L 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- 150000004706 metal oxides Chemical class 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000004584 polyacrylic acid Substances 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 239000012047 saturated solution Substances 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 239000004677 Nylon Substances 0.000 description 1
- 229920002292 Nylon 6 Polymers 0.000 description 1
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 238000006356 dehydrogenation reaction Methods 0.000 description 1
- 238000004925 denaturation Methods 0.000 description 1
- 230000036425 denaturation Effects 0.000 description 1
- SOCTUWSJJQCPFX-UHFFFAOYSA-N dichromate(2-) Chemical compound [O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O SOCTUWSJJQCPFX-UHFFFAOYSA-N 0.000 description 1
- AXZAYXJCENRGIM-UHFFFAOYSA-J dipotassium;tetrabromoplatinum(2-) Chemical compound [K+].[K+].[Br-].[Br-].[Br-].[Br-].[Pt+2] AXZAYXJCENRGIM-UHFFFAOYSA-J 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000003014 ion exchange membrane Substances 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229920001778 nylon Polymers 0.000 description 1
- 150000001282 organosilanes Chemical class 0.000 description 1
- VLTRZXGMWDSKGL-UHFFFAOYSA-N perchloric acid Chemical class OCl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-N 0.000 description 1
- 150000002978 peroxides Chemical class 0.000 description 1
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 239000004926 polymethyl methacrylate Substances 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 239000004800 polyvinyl chloride Substances 0.000 description 1
- 229920000915 polyvinyl chloride Polymers 0.000 description 1
- 229910001487 potassium perchlorate Inorganic materials 0.000 description 1
- 238000001223 reverse osmosis Methods 0.000 description 1
- BAZAXWOYCMUHIX-UHFFFAOYSA-M sodium perchlorate Chemical compound [Na+].[O-]Cl(=O)(=O)=O BAZAXWOYCMUHIX-UHFFFAOYSA-M 0.000 description 1
- 229910001488 sodium perchlorate Inorganic materials 0.000 description 1
- 238000000807 solvent casting Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- 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
- B01D67/0081—After-treatment of organic or inorganic membranes
- B01D67/0093—Chemical modification
-
- 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
- B01D67/0023—Organic membrane manufacture by inducing porosity into non porous precursor membranes
- B01D67/003—Organic membrane manufacture by inducing porosity into non porous precursor membranes by selective elimination of components, e.g. by leaching
Description
【発明の詳細な説明】
この発明は、例えば透過分子に対する選択性が
良く、しかも透過速度の早い安定な分離膜を比較
的簡単に作成できる多孔質膜の製造法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a porous membrane, which can relatively easily produce a stable separation membrane with good selectivity for permeable molecules and a high permeation rate.
従来分離膜は種々のものが製作されているが、
酢酸セルロースを主体とする逆浸透膜、酸素富化
膜のオルガノシラン膜等はいずれも多孔質膜上に
スキン層と呼ばれる密な膜を付加して複合膜構造
としたものが多く、これ等の複合構造の分離膜は
圧密化、変性等の問題が生じ、良質な膜は少な
い。 Conventionally, various separation membranes have been manufactured, but
Reverse osmosis membranes mainly made of cellulose acetate, organosilane membranes for oxygen enrichment, etc. often have a composite membrane structure by adding a dense membrane called a skin layer on top of a porous membrane. Separation membranes with composite structures have problems such as compaction and denaturation, and there are few high-quality membranes.
一方分離効率の良いイオン交換膜については、
分離生成に対して限界があり、連続的に使用する
場合には何度か再生させる必要がある。したがつ
て選択性が良く、しかも透過速度が大きく、安定
な分離膜は現在のところ得られておらず、その開
発は発展途上にある。 On the other hand, regarding ion exchange membranes with good separation efficiency,
There is a limit to separate production, and when used continuously, it is necessary to regenerate it several times. Therefore, a stable separation membrane with good selectivity and high permeation rate has not yet been obtained, and its development is still in progress.
本願発明者等は、上記実情に鑑み過去の分離膜
の欠点を補うような多孔質膜を製造する目的で鋭
意研究の結果、酸化剤を基材中に一様に混合させ
て高分子膜を作成するとともに、この高分子膜を
酸化雰囲気中で内部に含まれる酸化剤を酸化させ
ることにより、所期の目的とする多孔質膜を得る
ことができたのである。 In view of the above-mentioned circumstances, the inventors of the present application have conducted extensive research with the aim of manufacturing a porous membrane that compensates for the shortcomings of past separation membranes, and have developed a polymer membrane by uniformly mixing an oxidizing agent into the base material. By creating this polymer membrane and oxidizing the oxidizing agent contained inside it in an oxidizing atmosphere, they were able to obtain the desired porous membrane.
即ち、従来高分子材料に対しては抗酸化剤を混
合して安定化を図ることが行われて来たが、酸化
剤を混ぜて多孔質化を図ることは行われていない
が、本願発明者等は酸化剤の多くは酸化後、安定
な金属酸化物に変化してしまうこと、更に金属酸
化物は高分子鎖の間に介在して二次結合を形成し
て高分子材料の安定化に役立つであろうとの推定
のもとに、酸化剤を均質に混ぜて高分子膜を形成
し、酸化剤周辺の高分子鎖を適当に酸化して高分
子膜に孔を形成する研究を行つたところ分離膜と
して最適な多孔質膜を得ることができ、この発明
を完成したものである。 That is, conventionally, polymeric materials have been stabilized by mixing antioxidants with them, but adding oxidizing agents to make them porous has not been done. They have found that most oxidizing agents change into stable metal oxides after oxidation, and that metal oxides interpose between polymer chains and form secondary bonds, stabilizing polymer materials. Based on the assumption that this would be useful, we conducted research on forming pores in the polymer membrane by homogeneously mixing an oxidizing agent and oxidizing the polymer chains around the oxidizing agent appropriately. In the end, we were able to obtain a porous membrane suitable for use as a separation membrane, thus completing this invention.
この発明において使用する酸化剤としては各種
の酸化剤を使用することができるが、過マンガン
酸塩或いは過塩素酸塩等の過酸化物が適当であ
る。 Various oxidizing agents can be used as the oxidizing agent in this invention, but peroxides such as permanganates and perchlorates are suitable.
また高分子膜としては種々のものを使用するこ
とができるが、例えば酢酸セルロース、ポリアク
リル酸エステル、ナイロン等に適用できる。 Further, various polymer membranes can be used, and for example, cellulose acetate, polyacrylic acid ester, nylon, etc. can be used.
以上の酸化剤を均質に分散させて高分子膜を作
成するのは、例えば上記酸化剤をアセトン、酢酸
エチル等の有機溶媒に溶解して酸化剤溶液を作
り、また高分子膜基材を適当な有機溶媒に溶解し
て高分子溶液を作り、これ等の溶液の適当量を加
え、ミキサー或いは超音波等により均質に混合す
る。次に、この混合溶液を例えば平板上に流延し
てソルベントキヤスト法により酸化未処理膜を形
成する。 To create a polymer membrane by homogeneously dispersing the above oxidizing agent, for example, the oxidizing agent is dissolved in an organic solvent such as acetone or ethyl acetate to prepare an oxidizing agent solution, and the polymer membrane base material is A polymer solution is prepared by dissolving it in an organic solvent, and an appropriate amount of these solutions is added and mixed homogeneously using a mixer or ultrasonic waves. Next, this mixed solution is cast, for example, on a flat plate to form an oxidized untreated film by a solvent casting method.
この膜は光、酸素、オゾン、酸、電子線、中性
子線等の酸化雰囲気中で適当時間処理することに
より、内部に均質に含まれる酸化剤の酸化が促進
され、以上の高分子膜は多孔質化される。 By treating this film in an oxidizing atmosphere such as light, oxygen, ozone, acid, electron beam, or neutron beam for an appropriate period of time, the oxidation of the oxidizing agent homogeneously contained inside is promoted. Qualified.
なお酸化剤として過マンガン酸カリ等を使用し
た場合は、その酸化は下記のように脱水素反応が
基礎であり、また膜中に残存する酸化マンガンは
次の酸化段階で触媒作用等があり、過塩素酸カリ
等の酸化剤を使用した場合に比べて大きな穴を形
成することができる。 If potassium permanganate or the like is used as an oxidizing agent, the oxidation is based on a dehydrogenation reaction as shown below, and the manganese oxide remaining in the film has a catalytic effect in the next oxidation step. Larger holes can be formed than when using an oxidizing agent such as potassium perchlorate.
KMnO4＋3H→MnO2＋KOH＋H2O
また穴の大きさ、形状等は酸化処理液の種類、
或いは使用する強酸、蟻酸、過酸化水素、電子衝
撃、光照射等の選択によつても変わる。 KMnO 4 +3H→MnO 2 +KOH+H 2 O Also, the size and shape of the holes depend on the type of oxidation treatment solution.
Alternatively, it may vary depending on the selection of strong acid, formic acid, hydrogen peroxide, electron impact, light irradiation, etc. used.
一方、穴形成の際に生じたラヂカル、反応生成
物は、分離膜として使用する場合、新たな分離機
能を付加する可能性も大きいが、その反面膜中に
残存すると、望ましくない場合もある。このよう
な場合には、これ等のラヂカル、反応生成物を取
り除く処理を施さなければならない。 On the other hand, when used as a separation membrane, radicals and reaction products generated during hole formation have a high possibility of adding a new separation function, but on the other hand, if they remain in the membrane, they may be undesirable. In such cases, treatment must be performed to remove these radicals and reaction products.
なお酸化剤として重クロム酸塩を使用する場合
には、高分子膜中での分散性が悪く、現在までの
ところ余り良好な結果が得られていない。 Note that when dichromate is used as an oxidizing agent, it has poor dispersibility in the polymer membrane, and so far good results have not been obtained.
また高分子膜基材が有機溶媒に可溶の場合、酸
化剤をアセトン或いは酢酸エチル等に溶かして上
記高分子膜基材の溶液と混合し、更にキヤスト法
で酸化未処理膜を作成することが最も好ましい方
法である。 If the polymer membrane base material is soluble in an organic solvent, an oxidizing agent can be dissolved in acetone or ethyl acetate, mixed with the solution of the polymer membrane base material, and an unoxidized membrane can be created by a casting method. is the most preferred method.
以下、この発明の実施例を示す。 Examples of this invention will be shown below.
実施例 １
酢酸セルロースをアセトンに溶解して約１％濃
度の溶液を作成した。酸化剤には過マンガン酸カ
リを選び、アセトンに溶解し飽和溶液を作成し
た。Example 1 Cellulose acetate was dissolved in acetone to create a solution with a concentration of about 1%. Potassium permanganate was chosen as the oxidizing agent and dissolved in acetone to create a saturated solution.
次に、高分子溶液10部に対して酸化剤溶液１部
を加え、超音波混合を行い、これをガラス板上に
流延して空気共存下で風乾すると、疎ではあるが
直径５ミクロン程度の穴が浅く形成された。この
膜を蟻酸中に浸漬して水洗すると、更に多孔質化
された膜が得られた。 Next, 1 part of the oxidizing agent solution was added to 10 parts of the polymer solution, ultrasonic mixing was performed, and this was cast onto a glass plate and air-dried in the presence of air. A shallow hole was formed. When this membrane was immersed in formic acid and washed with water, a more porous membrane was obtained.
実施例 ２
ポリアクリル酸のポリメチルメタクリレートを
酢酸エチルに溶解して１％溶液を作成した。酸化
剤に過マンガン酸カリを用いる場合には、アセト
ンを、過塩素酸ナトリウムを用いる場合には酢酸
エチルを溶媒にして飽和溶液を作成した。この高
分子溶液10部に対し、酸化剤溶液１部を加え、実
施例１と同様にして酸化未処理膜を作成した。こ
れを蟻酸で処理すると、穴の直径１ミクロン以下
の多孔質膜を得ることができた。Example 2 A 1% solution was prepared by dissolving polymethyl methacrylate of polyacrylic acid in ethyl acetate. When potassium permanganate was used as the oxidizing agent, a saturated solution was prepared using acetone, and when sodium perchlorate was used, ethyl acetate was used as the solvent. An unoxidized membrane was prepared in the same manner as in Example 1 by adding 1 part of an oxidizing agent solution to 10 parts of this polymer solution. When this was treated with formic acid, a porous membrane with pores of 1 micron or less in diameter could be obtained.
この場合、酸化剤の種類、蟻酸による処理時
間、処理温度等によつて穴構造の異なる多孔質膜
が得られた。 In this case, porous membranes with different hole structures were obtained depending on the type of oxidizing agent, treatment time with formic acid, treatment temperature, etc.
実施例 ３
ナイロン―６を蟻酸に溶解して２％溶液を作成
し、この溶液に過マンガン酸カリを直接0.1％程
度溶解してキヤスト法で製膜した。これを10％程
度の過酸化水素で処理して多孔質膜が得られた。Example 3 Nylon-6 was dissolved in formic acid to prepare a 2% solution, and about 0.1% of potassium permanganate was directly dissolved in this solution to form a film by a casting method. A porous membrane was obtained by treating this with approximately 10% hydrogen peroxide.
実施例 ４
ポリカーボネート、ポリ塩化ビニール、ポリス
チレンをそれぞれテトラヒドロフランに溶解して
１〜２％濃度の溶液を作成した。一方実施例２と
同様にして酸化剤溶液を作成した。この酸化剤溶
液を、高分子溶液10部に対して１〜５部混合し、
キヤスト法で製膜して酸化未処理膜を作成した。Example 4 Polycarbonate, polyvinyl chloride, and polystyrene were each dissolved in tetrahydrofuran to prepare a solution with a concentration of 1 to 2%. On the other hand, an oxidizing agent solution was prepared in the same manner as in Example 2. Mix 1 to 5 parts of this oxidizing agent solution to 10 parts of the polymer solution,
An unoxidized film was formed by casting.
これ等の場合、溶剤の蒸発速度が特に早いの
で、得られた酸化未処理膜を10％濃度の過酸化水
素水を浸漬し、数時間酸化処理を行い、水洗、乾
燥して多孔質膜を得た。 In these cases, the evaporation rate of the solvent is particularly fast, so the resulting unoxidized membrane is immersed in 10% hydrogen peroxide solution, oxidized for several hours, washed with water, and dried to form a porous membrane. Obtained.
Claims (1)
作成し、次いで得られた高分子膜を酸化雰囲気中
で酸化することを特徴とする多孔質膜の製造法。 ２ 酸化剤と高分子基材の有機溶剤溶液を混合し
てキヤスト法により高分子膜を作成する特許請求
の範囲第１項記載の方法。 ３ 酸化剤の有機溶剤としてアセトン、酢酸エチ
ルを使用する特許請求の範囲第１項又は第２項記
載の方法。[Claims] 1. A porous membrane characterized in that a polymer membrane is created by uniformly mixing an oxidizing agent into a base material, and then the obtained polymer membrane is oxidized in an oxidizing atmosphere. Manufacturing method. 2. The method according to claim 1, wherein a polymer film is created by a casting method by mixing an oxidizing agent and an organic solvent solution of a polymer base material. 3. The method according to claim 1 or 2, wherein acetone or ethyl acetate is used as the organic solvent of the oxidizing agent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58081506A JPS59206440A (en) | 1983-05-10 | 1983-05-10 | Production of porous membrane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58081506A JPS59206440A (en) | 1983-05-10 | 1983-05-10 | Production of porous membrane |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59206440A JPS59206440A (en) | 1984-11-22 |
| JPS634862B2 true JPS634862B2 (en) | 1988-02-01 |
Family
ID=13748240
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58081506A Granted JPS59206440A (en) | 1983-05-10 | 1983-05-10 | Production of porous membrane |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59206440A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0621181B2 (en) * | 1987-01-12 | 1994-03-23 | テルモ株式会社 | Method for producing hydrophilic polyvinylidene fluoride porous membrane |
| US5215554A (en) * | 1991-06-12 | 1993-06-01 | Permea, Inc. | Membranes having enhanced selectivity and method of producing such membranes |
-
1983
- 1983-05-10 JP JP58081506A patent/JPS59206440A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59206440A (en) | 1984-11-22 |
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