JPH026849B2 - - Google Patents
Info
- Publication number
- JPH026849B2 JPH026849B2 JP57129389A JP12938982A JPH026849B2 JP H026849 B2 JPH026849 B2 JP H026849B2 JP 57129389 A JP57129389 A JP 57129389A JP 12938982 A JP12938982 A JP 12938982A JP H026849 B2 JPH026849 B2 JP H026849B2
- Authority
- JP
- Japan
- Prior art keywords
- hollow
- liquid
- spinning
- inner diameter
- injected
- 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 - Lifetime
Links
- 239000012510 hollow fiber Substances 0.000 claims description 30
- 239000007788 liquid Substances 0.000 claims description 24
- 238000009987 spinning Methods 0.000 claims description 13
- 229920002492 poly(sulfone) Polymers 0.000 claims description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 11
- 239000011347 resin Substances 0.000 claims description 10
- 229920005989 resin Polymers 0.000 claims description 10
- 238000004804 winding Methods 0.000 claims description 8
- 238000001891 gel spinning Methods 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 239000000835 fiber Substances 0.000 description 5
- 239000011550 stock solution Substances 0.000 description 5
- 238000001879 gelation Methods 0.000 description 4
- 239000012528 membrane Substances 0.000 description 4
- 238000000926 separation method Methods 0.000 description 4
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 3
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- 230000001112 coagulating effect Effects 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000001878 scanning electron micrograph Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 239000004721 Polyphenylene oxide Substances 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000635 electron micrograph Methods 0.000 description 1
- RTZKZFJDLAIYFH-UHFFFAOYSA-N ether Substances CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 238000002074 melt spinning Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000005416 organic matter Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 1
- 229920006380 polyphenylene oxide Polymers 0.000 description 1
- -1 polypropylene Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 description 1
- 229920000036 polyvinylpyrrolidone Polymers 0.000 description 1
- 239000001267 polyvinylpyrrolidone Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000002562 thickening agent Substances 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Landscapes
- Separation Using Semi-Permeable Membranes (AREA)
- Artificial Filaments (AREA)
Description
【発明の詳細な説明】
本発明は、ポリスルホン樹脂中空糸の製造法に
関する。更に詳しくは、乾湿式紡糸法による偏肉
のないポリスルホン樹脂中空糸の製造法に関す
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing polysulfone resin hollow fibers. More specifically, the present invention relates to a method for producing polysulfone resin hollow fibers without uneven thickness using a dry-wet spinning method.
ポリスルホン樹脂は、酸化に強いスルホン結
合、強じん性と熱安定性とを与えるエーテル結合
および耐熱性を向上させるベンゼン環などを分子
の骨格構造中にそれぞれ含んでいるので、バラン
スのとれたすぐれた性質を持つている。即ち、機
械的強度はポリフエニレンオキシド樹脂とほぼ同
等で、熱変形温度(174℃)はポリプロピレン樹
脂に次いで高く、特に高温での耐クリープ性がす
ぐれており、耐化学薬品性にすぐれ、酸やアルカ
リに侵されないといつた性質を備え、しかもそれ
は中空糸への紡糸も容易なところから、分離用膜
材料としての中空糸として、有機溶剤の分離、有
機物の回収、排水処理などに苛酷な条件(高温、
強酸性または強アルカリ性など)でも、いずれも
有効に使用することができる。 Polysulfone resin has a well-balanced and excellent structure, as it contains sulfone bonds that are resistant to oxidation, ether bonds that provide toughness and thermal stability, and benzene rings that improve heat resistance. It has a characteristic. In other words, its mechanical strength is almost the same as that of polyphenylene oxide resin, its heat distortion temperature (174°C) is second only to polypropylene resin, and it has particularly excellent creep resistance at high temperatures, excellent chemical resistance, and acid resistance. It has properties such as not being attacked by alkalis and alkalis, and it is also easy to spin into hollow fibers, making it suitable for use as a separation membrane material in harsh applications such as separation of organic solvents, recovery of organic matter, and wastewater treatment. Conditions (high temperature,
(strongly acidic or strongly alkaline) can be effectively used.
かかる用途に用いられるポリスルホン樹脂から
の中空糸の製造は、ポリスルホン樹脂の高濃度溶
液である紡糸原液(ドープ液)を二重円環ノズル
から押出し、数cm〜数10cmの間を自然落下させた
後、水またはそれを主成分とするゲル化浴中に導
き、そこでゲル化成形させることにより行われ、
この際中空部の内部には液体を注入し、中空部の
維持を図つている。これには、紡糸原液に対して
凝固性の液体、例えば水、アルコール、アセトン
またはそれらの混合液などが従来用いられてい
る。 To manufacture hollow fibers from polysulfone resin used in such applications, a spinning stock solution (dope solution), which is a highly concentrated solution of polysulfone resin, is extruded through a double annular nozzle and allowed to fall naturally over a range of several centimeters to several tens of centimeters. After that, it is introduced into water or a gelling bath mainly composed of water and gelled there.
At this time, liquid is injected into the hollow part to maintain the hollow part. For this purpose, a liquid that coagulates the spinning dope, such as water, alcohol, acetone, or a mixture thereof, has conventionally been used.
ところで、中空糸の中空部を維持するため、そ
の内部に凝固性の液体を注入する場合、ノズルの
外側環状部から吐出した紡糸原液は、ノズルの内
側中空部から注入されたこの液体と接触すると直
ちに中空糸の内側からゲル化を開始し、その後内
側のゲル化層は徐々に発達して行くが、紡糸され
た中空糸にドラフトをかけて延伸する際、中空部
に凝固性の液体が注入されるとノズル部からの急
激なゲル化によつて、糸切れが多発する現象がみ
られる。また、糸切れだけではなく、中空糸が周
方向に縮むため中空糸断面の内壁の形状が円形に
はならず、このような中空糸を分離用膜材料とし
て用いた場合には、ロ過性能が低下するといつた
欠点がもたらされる。 By the way, when a coagulating liquid is injected into the hollow fiber to maintain the hollow part, when the spinning stock solution discharged from the outer annular part of the nozzle comes into contact with this liquid injected from the inner hollow part of the nozzle, Gelation immediately starts from the inside of the hollow fiber, and the gelled layer on the inside gradually develops. However, when the spun hollow fiber is drafted and stretched, a coagulating liquid is injected into the hollow part. When this happens, rapid gelation from the nozzle part causes frequent thread breakage. In addition to fiber breakage, the hollow fibers shrink in the circumferential direction, so the shape of the inner wall of the hollow fiber cross section does not become circular, and when such hollow fibers are used as a separation membrane material, the filtration performance A decrease in this brings about the disadvantages.
かかる偏肉現象について更に検討するに、乾湿
紡糸法に限らず、溶融紡糸法その他の紡糸法によ
つて中空糸を製造する場合、二重円環ノズルから
吐出した未硬化(未ゲル化)の中空流を延伸して
いるので、得られた中空糸の外径および内径は、
ノズルのそれらよりも小さいのが普通である。 To further examine this uneven thickness phenomenon, when producing hollow fibers not only by dry-wet spinning but also by melt spinning or other spinning methods, uncured (ungelled) fibers discharged from a double annular nozzle are Since the hollow fiber is drawn, the outer diameter and inner diameter of the obtained hollow fiber are
They are usually smaller than those of the nozzle.
ところで、ポリスルホン樹脂紡糸原液を乾湿式
紡糸し、延伸によつて所望の糸径を有する中空糸
を製造する際、二重円環ノズルの内側から水など
のゲル化に関与する液体を注入液体として流す
と、ノズルから吐出した中空流は、その部から直
ちにゲル化を開始し、この注入液体と接している
部分では、最初ノズルの内径と同じ径を有する薄
い膜が生成し、その膜がその後延伸される。延伸
をかけることによつて、中空流の内、外径は次第
に小さくなるが、膜の厚さが薄いため、内径側が
円形のまま縮小せず、しわの寄つた状態でゲル化
を完了させる(第2図参照)。 By the way, when dry-wet spinning a polysulfone resin spinning dope and producing hollow fibers having a desired diameter by drawing, a liquid involved in gelation such as water is injected from the inside of a double annular nozzle as an injected liquid. When flowing, the hollow flow discharged from the nozzle immediately starts to gel from that part, and in the part that is in contact with this injection liquid, a thin film with the same diameter as the inner diameter of the nozzle is initially formed, and then this film Stretched. By stretching, the inner and outer diameters of the hollow flow gradually become smaller, but because the membrane is thin, the inner diameter remains circular and does not shrink, and gelation is completed in a wrinkled state ( (See Figure 2).
ところで、中空糸の内、外径(mm)は、紡糸原
液量(mm3/分)、注入液体量(mm3/分)および
巻取速度(mm/分)によつてほぼ決まり、それら
はそれぞれ次式で表わすことができる。 By the way, the inner and outer diameters (mm) of the hollow fiber are almost determined by the amount of spinning dope (mm 3 /min), the amount of injected liquid (mm 3 /min), and the winding speed (mm / min), and these are Each can be expressed by the following formula.
外径={4/π×(巻取速度)
×(紡糸原液量+注入液体量)}1/2 ……(1)
内径={4/π×(巻取速度)
×(注入液体量)}1/2 ……(2)
そこで、延伸時に内径側が不均一に縮小するの
を防止するという課題を解決するために、延伸を
かけても中空糸の内径がノズルの内径に等しいか
あるいはそれよりも大きくなるような条件を注入
液体量を調節することによつて設定すべく、前記
(2)式を変形すると、注入液体量(mm3/分)が次
式
π×(巻取速度)/4×(ノズル内径)2 ……(3)
で示された値に等しいかあるいはそれよりも大き
くしたとき、延伸中空糸の内径がノズルの内径に
等しいかあるいはそれよりも大きくなり、内径側
も円形にして偏肉のない中空糸が得られることが
分つた。 Outer diameter = {4/π x (winding speed) x (spinning stock solution amount + injected liquid amount)} 1/2 ...(1) Inner diameter = {4/π x (winding speed) x (injected liquid amount) } 1/2 ...(2) Therefore, in order to solve the problem of preventing the inner diameter side from shrinking unevenly during stretching, it is necessary to make sure that the inner diameter of the hollow fiber is equal to or less than the inner diameter of the nozzle even after stretching. In order to set the conditions such that the amount becomes larger than the above-mentioned
Transforming equation (2), the amount of injected liquid (mm 3 /min) is equal to or less than the value shown by the following equation: π x (winding speed) / 4 x (nozzle inner diameter) 2 ...(3) It has been found that when the diameter of the drawn hollow fiber is made larger than that of the nozzle, the inner diameter of the drawn hollow fiber becomes equal to or larger than the inner diameter of the nozzle, and the inner diameter side is also made circular to obtain a hollow fiber with no uneven thickness.
従つて、本発明は、ポリスルホン中空糸の製造
法に係り、ポリスルホン中空糸は、ポリスルホン
紡糸原液を乾湿式紡糸するに際し、中空部を維持
させるための注入液体として水またはそれを主成
分とする液体を用い、かつその注入液体量を前記
式(3)で示された値に等しいかあるいはそれより大
きくなるような条件下で紡糸することにより製造
される。 Therefore, the present invention relates to a method for producing polysulfone hollow fibers, which uses water or a liquid mainly composed of water or a liquid containing water as an injection liquid to maintain the hollow portion during dry-wet spinning of a polysulfone spinning dope. It is produced by spinning under conditions such that the amount of injected liquid is equal to or larger than the value shown in the above formula (3).
即ち、一定の内径を有する二重円環ノズルを用
いた場合、乾湿式紡糸された中空糸の巻取速度と
注入液体量を調節するだけで、内径側が円形で偏
肉のない中空糸を得ることができ(第1図参照)、
かかる中空糸は、一定の厚さを有することから、
延伸時に糸切れが発生する割合が少なく、また分
離用膜材料として用いた場合に良好なロ過性能を
示すという効果を奏する。なお、注入液体量の調
節は、例えばギアポンプの回転数を調節すること
によつて行われる。 In other words, when using a double ring nozzle with a constant inner diameter, hollow fibers with a circular inner diameter and no uneven thickness can be obtained by simply adjusting the winding speed and the amount of liquid injected into the dry-wet-spun hollow fibers. (see Figure 1),
Since such hollow fibers have a certain thickness,
It has the effect of having a low rate of yarn breakage during stretching and exhibiting good filtration performance when used as a separation membrane material. Note that the amount of liquid to be injected is adjusted, for example, by adjusting the rotation speed of the gear pump.
次に、実施例について本発明を説明する。 Next, the present invention will be explained with reference to examples.
実施例
いずれも重量で15%のポリスルホン(UCC社
製品P―1700)、84%のジメチルホルムアミドお
よび1%のポリビニルピロリドン(増粘剤)から
調製された紡糸原液を、内径1.0mm、外径2.0mmの
二重環状ノズルから14ml/分の吐出量で外側環状
部から吐出させ、その際内側中空部から注入液体
として水を9ml/分(9×103mm3/分)の注入量
で同時に送り込み、7.5cmの間を自然落下させ、
ゲル化浴中に浸漬させた後、44m/分(44×103
mm3/分)×4400×(0.1)2の巻取速度で中空糸を巻
取り、外径1.4mm、内径1.0mmの中空糸を製造し
た。Example A spinning stock solution prepared from 15% polysulfone (UCC product P-1700), 84% dimethylformamide, and 1% polyvinylpyrrolidone (thickener) by weight was prepared with an inner diameter of 1.0 mm and an outer diameter of 2.0 mm. A double annular nozzle with a diameter of 1.5 mm is used to discharge water from the outer annular part at a rate of 14 ml/min, and at the same time water is injected from the inner hollow part at a rate of 9 ml/min (9 x 10 3 mm 3 /min). Feed it and let it fall naturally between 7.5cm,
After being immersed in the gelling bath, the speed of 44 m/min (44×10 3
The hollow fiber was wound at a winding speed of mm 3 /min) x 4400 x (0.1) 2 to produce a hollow fiber with an outer diameter of 1.4 mm and an inner diameter of 1.0 mm.
(3)式の値:
π×(44×103)/4×(1.0)2=34.6×103mm3/
分
この値は、注入液体量9×103mm3/分より大き
い。Value of formula (3): π×(44×10 3 )/4×(1.0) 2 =34.6×10 3 mm 3 /
min This value is greater than the injected liquid volume of 9×10 3 mm 3 /min.
得られた中空糸は、第1図にその断面の繊維構
造(倍率50倍)が走査型電子顕微鏡写真として示
されている如く、中空部が真円に近い、偏肉のな
い断面を有している。 The obtained hollow fiber had a cross section with a hollow portion close to a perfect circle and no uneven thickness, as shown in Figure 1 as a scanning electron micrograph showing the fiber structure of its cross section (50x magnification). ing.
比較例
実施例において、紡糸原液吐出量を30ml/分、
注入液体量を30ml/分、(30×103mm3/分)、自然
落下距離7.5cmとしてゲル化浴中に浸漬し、また
巻取速度を26m/分(26×103mm3/分)として、
外径が0.6mmの中空糸を製造した。Comparative Example In the example, the spinning stock solution discharge amount was 30ml/min.
The injection liquid volume was 30 ml/min (30×10 3 mm 3 /min), the natural fall distance was 7.5 cm, and the winding speed was 26 m/min (26×10 3 mm 3 /min). ) as,
Hollow fibers with an outer diameter of 0.6 mm were manufactured.
(3)式の値:
π×(26×103)/4×(1.0)2=20.4×103mm3/
分
この値は、注入液体量30×103mm3/分より小さ
い。Value of formula (3): π×(26×10 3 )/4×(1.0) 2 =20.4×10 3 mm 3 /
min This value is less than the injected liquid volume of 30×10 3 mm 3 /min.
得られた中空糸は、第2図にその3本の断面の
繊維構造(倍率50倍)が走査型電子顕微鏡写真と
して示されている如く、中空部が周方向に3個所
縮み、偏肉部を形成していることが分る。 As shown in Figure 2, the fiber structure of the three cross sections of the obtained hollow fiber is shown as a scanning electron micrograph (50x magnification). It can be seen that it forms
第1図は実施例で、また第2図は比較例でそれ
ぞれ得られた中空糸の断面の繊維構造を示す電子
顕微鏡写真である。
FIG. 1 is an electron micrograph showing the fiber structure of a cross section of a hollow fiber obtained in an example and FIG. 2 is a comparative example.
Claims (1)
に際し、中空部を維持させるための注入液体とし
て水またはそれを主成分とする液体を用い、かつ
その注入液体量を次式 π×(巻取速度)/4×(ノズル内径)2 で示された値に等しいかあるいはそれより大きく
なるような条件下で紡糸することを特徴とするポ
リスルホン樹脂中空糸の製造法。[Scope of Claims] 1. When dry-wet spinning a polysulfone resin spinning dope, water or a liquid mainly composed of water is used as the injected liquid to maintain the hollow part, and the amount of the injected liquid is expressed by the following formula π× A method for producing a polysulfone resin hollow fiber, which comprises spinning under conditions such that the value is equal to or greater than the value expressed by (winding speed)/4×(nozzle inner diameter) 2 .
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP12938982A JPS5921721A (en) | 1982-07-23 | 1982-07-23 | Preparation of hollow filament of polysulfone resin |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP12938982A JPS5921721A (en) | 1982-07-23 | 1982-07-23 | Preparation of hollow filament of polysulfone resin |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS5921721A JPS5921721A (en) | 1984-02-03 |
JPH026849B2 true JPH026849B2 (en) | 1990-02-14 |
Family
ID=15008364
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP12938982A Granted JPS5921721A (en) | 1982-07-23 | 1982-07-23 | Preparation of hollow filament of polysulfone resin |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5921721A (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60246812A (en) * | 1984-05-18 | 1985-12-06 | Daicel Chem Ind Ltd | Hollow polysulfone based resin fiber |
JP4666248B2 (en) * | 2004-05-27 | 2011-04-06 | 東洋紡績株式会社 | High strength high water permeability hollow fiber membrane blood purifier |
JP4599934B2 (en) * | 2004-08-10 | 2010-12-15 | 東洋紡績株式会社 | Hollow fiber membrane module |
JP2015221400A (en) * | 2014-05-22 | 2015-12-10 | Nok株式会社 | Manufacturing method of hollow fiber membrane for ultrafiltration membrane |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS54151614A (en) * | 1978-05-20 | 1979-11-29 | Nippon Zeon Co Ltd | Production of hollow fibers |
JPS5766113A (en) * | 1980-10-08 | 1982-04-22 | Kanegafuchi Chem Ind Co Ltd | Production of hollow fiber |
JPS5782515A (en) * | 1980-11-05 | 1982-05-24 | Kanegafuchi Chem Ind Co Ltd | Hollow fibrous membrane and its preparation |
-
1982
- 1982-07-23 JP JP12938982A patent/JPS5921721A/en active Granted
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS54151614A (en) * | 1978-05-20 | 1979-11-29 | Nippon Zeon Co Ltd | Production of hollow fibers |
JPS5766113A (en) * | 1980-10-08 | 1982-04-22 | Kanegafuchi Chem Ind Co Ltd | Production of hollow fiber |
JPS5782515A (en) * | 1980-11-05 | 1982-05-24 | Kanegafuchi Chem Ind Co Ltd | Hollow fibrous membrane and its preparation |
Also Published As
Publication number | Publication date |
---|---|
JPS5921721A (en) | 1984-02-03 |
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