JPS6022901A - Selective permeable hollow fiber - Google Patents

Abstract

PURPOSE:To provide excellent material permeability, contamination resistance, and sufficient mechanical strength to a hollow fiber for a permeable membrane by incorporating a copolymer having a polyethylene oxide unit. CONSTITUTION:A component A, for example, consists of acrylic or methacrylic ester expressed by the formula I or a vinyl monomer, etc. shown by the formula II, and a component B consists of a monomer or a polymer copolymerizable with the component A such as acrylic acid, methacrylic acid, methyl acrylate, etc. And a selectively permeable hollow fiber is constituted of a copolymer consisting of both components. In addition, the copolymer is required to contain >=1wt% n>=5 polyethylene oxide units contained in the components A.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a permselective hollow fiber assembly with excellent stain resistance of 1/1 and solute permeability.

(Disadvantages of conventional technology) In recent years, polymer materials have been increasingly applied to industrial and medical fields.
There is increasing interest in the use of selectively permeable membranes, so-called semipermeable membranes, for the separation of four (4) substances.

For example, many technical reports have been published on the use of membranes in fields such as reverse osmosis, dialysis, ultrafiltration, and gas separation. However, in these operations, there are problems in that the membrane is contaminated by the treatment substance, reducing the treatment capacity, and that the separation performance of the membrane itself is not necessarily sufficient.

As materials for such selectively permeable membranes, regenerated cellulose, various hillulose derivatives, acrylonitrile polymers, polyvinyl alcohol polymers, and polymethylmethacrylate-1-based polymers (A1) have been used as materials for such selectively permeable membranes.
[. Furthermore, for the purpose of improving stain resistance, synthetic polymers having 2-hydroxyethyl methacrylate = 1 to 2 hydrophilic components such as N-vinylpyrrolidone, acrylamide, or (meth)acrylic acid have been studied.

However, membranes made of these materials have insufficient permeability to substances such as water and solutes, or they have been introduced with a large amount of copolymerized components to increase dirtiness. The mechanical strength of the film decreased, and its functionality as a practical membrane was impaired. Furthermore, when these membranes are used to concentrate various protein solutions, sterilize liquid foods, or carry out ultrafiltration separation in wastewater treatment processes, the solute components (= J arrival, 1 product J: This causes a clogging phenomenon.
The intended operation was hindered. Alternatively, when these membranes are used for medical purposes and come into contact with blood or body fluids, they may adsorb various humoral components such as proteins and lipids, or they may absorb platelets,
It is assumed that the adhesion of formed substances such as white blood cells, red blood cells, and thromboblasts is inevitable, and that these lead to the formation of blood clots on the membrane surface and a decline in immune function due to the activation of the complement system. It was done.

(Objective of the Invention) A member of the present inventors has already proposed a medical hydride gel having polyethylene oxide units as a hydrophilic polymer material and published it as an IC (164064/1986). However, in Kagaru's proposal.

Although the stain resistance of the materials mentioned above has improved.

This was insufficient to provide a practical membrane material with permselectivity. As a result of our intensive research into the hydrophilic polymer material, we found that hollow fibers containing a copolymer having poly-dylene oxylide units have good material permeability and stain resistance. I have it.

We have found that this membrane can be put to practical use as a permselective membrane with sufficient mechanical strength, and have arrived at the present invention.

(Structure of the Invention) The permselective membrane 11 made of the polymer composition of the present invention has the following structure.

Polynylene f-ren Δ main body monomer with a degree of polymerization of 5 or more. and a polymerizable carbon-carbon double bond in one molecule (component 1), a polymerizable monomer containing 14 carbon atoms and a polymerizable carbon-carbon double bond in one molecule.
A copolymer consisting of a monomer having a carbon double bond (1) is used as a permselective hollow fiber.

Component (1) constituting the present invention is 1, for example, an acrylic acid or methacrylic acid ester represented by the general formula (1) % formula % (1) or a vinyl monomer represented by the general formula (2) etc.

Methods for producing these compounds containing f'l and [I] are well known.

- A special device due to its polymerizable carbon-carbon double bond.

Using the technique ', r at least 9 the usual radino-J initiator 2
For example, it can be easily polymerized using azobisisobutylonitrile, azobisdimedilba-1-noronyl-lyl, benzoyl peroxide, etc., and can also be copolymerized with other monomers or polymers. , a polymer composition containing polyethylene A fluoride units can be formed efficiently and with good reproducibility.

1 ton of polyethylene oxide in the polymer.

For example, it can be determined by conventional techniques such as elemental analysis, infrared absorption spectrum, and nuclear magnetic resonance spectroscopy.

Essentially any monomer or polymer C capable of copolymerizing with the copolymerization component (II) + and v component (1) constituting the polymer may be used.9 For example, 11j! As r1 form, acrylic acid, methacrylic acid))! 2, methyl acrylate, methyl methacrylate, dimylaminoedyl methacrylate, acrylic [Z double/vine. Dinylacetate, vinyl chloride, styrene, vinylidene chloride, 2-hydroxyethylmethacryle-1-,N-vinylpyrrolidone, acrylamide, cyan acrylamide, ethylene,
Examples include compounds having a carbon-carbon double bond such as propylene and butashikonine, and mixtures thereof.

Here, the polymer of components (1) and (II) can take any copolymerization form. Among these components, especially the component (1
) is methoxypolyethylene glycol monomethacrylate-1, and the component (11) to be copolymerized with this is acryloni-1-lyl or methyl methacrylate. A copolymer in which the component (11) is acryloni-1-lyl or methyl methacrylate is also preferably used in a normal amount.

In the polymer constituting the permselective hollow fiber shoulder of the present invention, polyethylene A with n≧5 contained in component (I)
It is necessary that at least 1% by weight or more of the ki(noid at position 115) is contained.To achieve this, the component ([) in the copolymer necessary to contain the polyethylene oxide contained in (I) weight fraction.

That is, it depends on n. For example, component (n) is methyl methacrylate-1-r-, component (1) is compound (1) and R1
= Cl-13, R2 = OCH3, when n = 9, it is necessary to have 0,255 mol% or more of (1) as the monomer intermediate, whereas when n = 100, may be 0.023 mol% or more.

When the polyethylene oxide unit content necessary to achieve the target performance is given to the hollow fiber, if the degree of polymerization of the polyethylene oxide unit is 71 < 5, the spinning stability will be poor and the resulting membrane will be difficult to machine. It cannot be used for reasons such as insufficient physical strength. 1゛That is, the permselective hollow that can be obtained in a platform in which the degree of polymerization of polyethylene oxide units is 72<5 and the content of polyethylene oxide units is less than 1% by weight! J&m is the property aimed at by the present invention.

In other words, it cannot have features such as suppression of various components and excellent substance permeability. The degree of polymerization of the polyethylene oxide unit is preferably 9 to 300, particularly preferably 20 to 10.
0, and the content of 9f poly]dethylene oxide units is 3 to 90% by weight.

Also, the loose copolymer component in the present invention.

A] Polymerizable compounds consisting of component (II) in the present invention and mixtures thereof, etc., and these are 1% by weight (as the weight ratio of polyethylene oxide units in the copolymer of components (1) and (II)). ) or more in the total polymer.

Next, as the solvent for the spinning dope used in the present invention, any solvent that can simultaneously dissolve the copolymer etc. can be used, such as dimethylformamide, dimethylsulfoxide, and dimethylacetamide.

N-methylpyrrolidone and the like are preferably used.

Mixtures of these compounds are also preferably used.

When dissolving the copolymer and its mixture in these solvents, it is necessary to consider the required performance (1) mechanical strength and spinnability. Zunawara.

The polymer concentration in the spinning stock solution is closely related to the permeability and mechanical strength of the membrane; if the concentration is too high, the membrane's permeability to substances will be lost, and if it is too low, the mechanical strength will decrease, making it impractical for practical use. In addition, the viscosity of the spinning stock solution is an important factor for IJ spinnability, and in order to form a good hollow fiber configuration, the polymer concentration [well, in the range of 5 to 50,000% should be used.

When the spinning stock solution is discharged from the spinneret, it is necessary to form a smooth yarn and at the same time maintain the hollow fiber shape sufficiently. The viscosity of the stock solution is an important factor for stable dispensing, and therefore it is possible to control the viscosity of the stock solution at the time of dispensing by adjusting the temperature of the nozzle. If not, the dimensions of the hollow machine string are approximately determined in the coagulation bath.When using a hollow nozzle with a hole diameter larger than the target size, the spinning stock solution is once released into the air.

After that, it is immersed in a coagulation bath to avoid coagulation. The so-called dry-wet spinning method is an effective method.

In order to maintain the shape of the hollow fibers, a liquid is injected into the inside of the hollow machine string. The liquid to be injected is 2
For example, a hydrophobic liquid such as a solvent for the spinning solution and a coagulant such as water or a (polyhydric) alcohol, or a mixture thereof, or a non-solvent for the copolymer or a mixture thereof, such as 11-octane, Aliphatic hydrocarbons such as liquid paraffin, fatty acid esters such as isopropyl myristate, etc. can also be used.

In addition, if the discharged yarn becomes glued due to temperature changes in the air or quickly forms a strong structure by solidification, use an inert gas such as nitrogen gas or air during self-suction or press-fitting. be able to.

Such a gas injection method is very advantageous from a process standpoint. In the case of a stock solution system in which gelation occurs due to temperature changes, gelation can be promoted by blowing cold air in the drying section.

In this case, the length of the aerial part, so-called dry part, is 30 mm or more. It may also gel due to temperature changes.

Alternatively, if the hollow m-fiber form is to be maintained only by coagulation with a stock solution that does not cause a rapid increase in viscosity, it is desirable to shorten the length of the dry section. If the length of the dry part is too long, the hollow fibers will have a small hollowness ratio (the ratio of the inner diameter to the outer diameter), and if the injection pressure is increased, the hollowness ratio will decrease before reaching the target hollowness ratio. A localized bulge will occur. Also, if it is too short, a sudden draft will be applied and the spinning will become unstable.1Usually, the length of the dry section is 1m+n or more and 100mm, preferably 3 sheaths or more and 50mm.
Set to a range of mm.

Coagulation baths typically contain a coagulant such as water or (polyhydric) alcohol;
Or it consists of a mixture with the solvent that constitutes the spinning dope. The composition of the coagulation bath greatly influences spinning stability and the membrane structure of hollow fibers depending on its coagulation properties. If the spinning dope has high coagulability.

Huge voids are generated in the hollow fiber membrane. In addition, if the coagulability becomes low, it becomes difficult to maintain the hollow fiber shape, so the composition must be appropriate, taking into account the properties of the stock solution.

The temperature of the coagulation bath greatly controls its coagulation properties and is also a major factor in the permeability of the membrane. That is, as the temperature of the bath increases, the permeability increases. Therefore, the coagulation bath composition is combined with the above-mentioned coagulation bath composition under appropriate conditions for the target permeation performance.

After coagulation, after washing thoroughly with water, in order to prevent the membrane structure of the hydrated hollow fibers from being destroyed by drying,
The water inside the membrane structure is replaced with glycerin or ethylene glycol. Furthermore, if necessary, one-dimensional stability can be imparted by heat treatment using an aqueous glycerin solution or the like.

(Effects of the Invention) Thus, the hollow fiber containing the polyethylene oxide unit-containing copolymer spun under appropriate conditions has excellent mechanical strength, and in addition to the anti-fouling effect on the treated membrane surface, it also has the ability to contain substances such as urea and vitamin 812. Even though the permeability has been significantly improved, the albumin blocking rate is still high, and excellent effects can be exhibited in terms of permselectivity. Therefore, they can be made into devices by known methods depending on their permselective characteristics and used for purposes such as reverse osmosis, dialysis, ultrafiltration, and gas separation. That is, for this purpose, the above-mentioned stock solution conditions such as the polyethylene oxide unit content of the co-Φ aggregate and the polymer concentration of the spinning stock solution, and the spinning threads 1. It is possible to arbitrarily adjust the two-selective permeability by appropriately selecting post-processing conditions and the like.

Hereinafter, J: will be described in more detail in Examples.

The present invention is not limited to these Examples.

Example 1 Methoxypolyethylene glycol methacrylate-1-, “
'M-23G' (polymerization degree of ethylene oxide part 23
2 molecules ff11112. 21g of Shin Nakamura Kogyo Co., Ltd.) and 3570g of dimethyl sulfoxide (hereinafter abbreviated as DMSO)
375 g of methyl methacrylate (hereinafter abbreviated as MMA) and 2,2'-azobis-2,4-dimethylvaleronitrile (hereinafter abbreviated as ADVN >1.190 g) to perform normal radical polymerization. -dah. Obtained M-2
The polyethylene oxide unit content measured by C-NMR of the 3G'' copolymerized polymethyl methacrylate (hereinafter abbreviated as 3PMMA) copolymer was 3.2% by weight;
The weight average molecular weight by method C was 228,000.

° High isotactic methyl methacrylate polymer (hereinafter abbreviated as iso-PMMA) with a weight average molecular weight ff of 1.66 million and polymerized with the above copolymer 350Q using a Grignard catalyst.
Add 70q to 980g of dimethyl sulfoxide and make 12
A spinning stock solution was prepared by stirring and dissolving at 0° C. for 12 hours. This spinning stock solution is transparent and has a falling ball viscosity of 11s-28803.
) was 360 poise at 11'0°C.

This spinning stock solution was transferred to a stock solution storage tank of a spinning device kept at 120° C., and then left for 15 hours to defoam.

The spinning device includes a storage tank, a gear pump, and a discharge section.

In particular, the temperature of the discharge section can be controlled independently of the others. This spinning device has an outer diameter of 1.8 mwn and an inner diameter of 1.8 mwn.
A cap having a hollow tube was installed in the cap hole consisting of a 5 m annular orifice.

While injecting nitrogen gas from the hollow mttt, the spinning stock solution was discharged into the air at a rate of 1.950/min using a gear pump. The temperature of the melon in the heated mouthpiece was 100'C.

The discharged yarn was cooled while reaching a coagulation bath installed 20 cm below the mouth surface, and then passed through the coagulation bath. The coagulation bath consisted of a 5% dimethyl sulfoxide aqueous solution at 12° C., and a guide roller was installed in the bath. After washing with water in a conventional manner, the sample was heat-treated with an aqueous glycerin solution, wound up into a skein, and cut into samples. The final winding speed was 28 m/min.

The hollow uA fibers of 'M-23G' copolymerized polymethyl methacrylate-1 thus obtained were 'completely transparent.

The inner diameter was 240μ and the film thickness was 40μ. Further, the strength of the hollow fiber measured using Tensilon (manufactured by Toyo Baldwin Co., Ltd.: LJM-111) was 47 g, and the elongation was 22%, indicating sufficient strength.

The hollow fiber was inserted into a glass case equipped with holes for reflux fluid at both ends, and a small dialysis device (mini-chia module) with an effective membrane area of 46 d was produced using a commercially available botting agent. This device was immersed in a constant temperature bath (37°C) and water pressure was applied to the inside of the hollow fiber.

The amount of water that permeates to the outside through the membrane in a certain period of time, the effective membrane area J3, and the permeation rate of water discharged from the membrane pressure difference H5
．． 4. ml/hr, mmH (1, vn2 [.

or.

Using the mini chia module, a urea aqueous solution is flowed inside the hollow fiber, and a large flow of water is counterflowed to the outside of the hollow fiber, and the pressure difference between the membranes is zero. Inner and outer entrances in the state.

As a guideline for solute permeability calculated from the urea concentration and flow direction at the outlet, the permeation membrane resistance of urea is 24.0 mi++/Cl1
1, and showed excellent performance as a semipermeable membrane.

A platelet suspension (PRP: 200,000 platelets/μm) was applied inside the hollow fiber at a flow rate of Q using a similar mini-chia module.
, 51/min (shear rate 200/Sec)
The mixture was circulated for 3 hours while being kept at 37°C.

After washing with physiological saline and fixing with 3% glutaraldehyde physiological saline, the protein (11) attached to the inner surface of the hollow fiber was measured by amino acid analysis.The attached amount was 2 μg/cy+
It was found that the inner surface of the hollow 111F was not contaminated.

Comparative Example 1 Grini (iso-PMMA 84 chassis with 7 catalysts)
G and methyl methacrylate polymer obtained by radical polymerization method (
168Q (hereinafter abbreviated as syn-PMMΔ) and methyl methacrylate copolymer 252Q, which is a copolymer of 2.5 mol% of p-styrene sulfonic acid sodium salt, were mixed in DMSOl 2
Spun yarn D obtained by dissolving in 96Q at 120°C; iM (11
Hollow fibers were obtained by the spinning method shown in Example 1. The hollow fiber obtained here has an inner diameter of 240 μ9, a membrane thickness of 40 μ, and a water permeation rate of 4.2 m.
l/hr-awnl-IQ ・TI, was 2. Further, after a platelet suspension circulation experiment was carried out in the same manner as in Example 1, the size of the attached protein was 20μ (1/a?).

Example 2 Methoxypolyethylene glycol methacrylate-1-”M
-100G" (tfi degree of ethylene oxide part 100. Molecule m4500. Manufactured by Toho Chemical Co., Ltd./Shin Nakamura Kogyo Co., Ltd.) 2'7.30 was dissolved in 1697 g of DMS, and polymerization started with MMA, 163 (J). ADV as a drug
N567mo was added and polymerization was carried out according to a known method. The polyethylene oxide unit content in the copolymer obtained by repeating this polymerization operation three times was 11.
It was 4% by weight.

175 g of the above copolymer and iso-PMMA35 (J) were added to 490 g of DMSO and stirred and dissolved at 120°C for 14 hours to prepare a spinning stock solution.The resulting spinning stock solution was heated to 110°C.
The viscosity was 1270 voids. This spinning stock solution was discharged while injecting nitrogen gas from the spinneret at a rate of 1.03 g/ln as in Example 1, cooled in the air, introduced into a coagulation bath consisting of water at 10°C, coagulated, washed with water, and heat treated. , glycerol substitution was performed, and the sample was wound onto a drum at 19 If/min. The inner diameter of the obtained hollow fibers was 220μ, and the film thickness was 32μ. A MiniDare module was prepared in the same manner as in Example 1, and the water permeation rate of this hollow fiber was measured to be 4.6 ml/br/eaves HO/m2. A protein adhesion test was carried out by refluxing a 1% aqueous solution of live serum albumin inside the hollow fibers of this minichia module at a shear rate of 115/Sec for 15 minutes. Thereafter, the water permeation rate measured again using the minithiamodicol was 4, In+1/old mm I-1 (1 T1
2, and the water permeability retention rate of the hollow II was 89%. The water permeability retention rate of the hollow fiber shown in Comparative Example 1 was 60%.
Therefore, it was found that the hollow fibers in this example suppressed clogging on the membrane surface due to protein adhesion.

Example 3 DM 182 parts of acrylonitrile and 78 parts of methoxypolyethylene glycol methacrylate h"MlooG"
In addition to 4 parts of S014, 9 polymerization initiators were added to ADVNl,
After polymerizing at 50° C. for 24 hours, it was reprecipitated with water/methanol and purified to obtain a 'M 100 G' copolymerized polyacrylonitrile.The polyethylene oxide units in the copolymer The content was 29%.

105 parts of the copolymer was added to 8024.5 parts of D M and dissolved with stirring at 80° C. for 8 hours. The spinning stock solution thus prepared was uniform and transparent, and had a viscosity of 130 voids at 290°C. Using the same spinning device as in Example 1, while injecting nitrogen gas from the hollow nozzle, the spinning dope was spread 6 m from the nozzle surface at a rate of 0.83(]/ll1in).
It was introduced into a coagulation bath consisting of an 8'C 26% DMSO aqueous solution placed below L11.

The material was coagulated, washed with water, heat treated, and wound at a speed of 19.5 m/min.

The inner diameter of the obtained hollow fibers was 200μ, and the film thickness was 35μ. The water permeation rate is 3.4 ml/hr・mm H(J
・At 1T12, the permeation membrane resistance of urea, J: and vitamin B12 is 10.2 min/am and 113 min/c.
+1+ showed very excellent solute permeability. Another 5%
The protein rejection rate measured from the concentration ratio of the stock solution and filtrate after passing through an aqueous solution of bovine serum albumin was 99.9% (7)
Time (7) Water (D permeation rate is 3, Qml/hr-m
ml-1 (1.Tl12), and was a semipermeable membrane with high 1-selective permeability.

In addition, the amount of attached protein after the platelet suspension circulation experiment measured by the same method as in Example 1 was 0.1 μO/ant, showing very good stain resistance.Example 4 Example 2 "M-100G" copolymerized PMMΔ was prepared in a similar manner. The content of the q1 position of polyethylene A kylide in the copolymer was 2368% by weight. The above copolymer i ooc+ was added to DMS0400G at 110°C.
Stir and dissolve for 5 hours to obtain a transparent spinning stock solution. The viscosity of the spinning dope was 445 voices at 90°C. Using the spinning apparatus of Example 1, the spinning stock solution was mixed with 1.0% of LJ gold.
18.5'nwll of nitrogen gas at a rate of 6CI/min
It was simultaneously discharged into the air while applying an injection pressure of Δq. The length of the dry section was set to 270,111 mm, and the tube was introduced into a coagulation bath consisting of a 5% DMSO aqueous solution at 16° C. while blowing cold air.

After coagulation and washing with water, it was replaced with a 60% aqueous glycerin solution, and further subjected to a 5% relaxation heat treatment with a 78% aqueous glycerin solution at 80° C., and then wound up at 191 Il/1 inr. The inner diameter of the obtained hollow m dark blue was 230μ and the film thickness was 34μ.

In the same manner as in Example 1, the membrane area 22a? The water permeation rate measured by preparing mini thiamodicol was 20,61
It was 111/hr-mml-1gmm1-l. Thereafter, the 1% bovine serum albumin aqueous solution was refluxed in the same manner as in Example 2, and the water permeation rate was 15,0 ml/br・m.
The water permeability retention rate was as high as 73% at mH(+ tn2), and it was found that the stain resistance was the same in this case as well.Also, when measured with a 5% albumin aqueous solution, the retention rate of albumin was 91%. %, virtually no albumin was permeated.

Comparative Example 2 Polymerization with Grignard catalyst; iso = PMM△50
(J and syn-PMM obtained by normal radical polymerization method
250 g of A was dissolved in DMSOl 200c+, and the spinning apparatus of Example 1 was used to obtain hollow fibers with an inner diameter of 250 μm and a membrane thickness of 30 μm. The hollow fiber was assembled into a minichia module, and the measured water permeation rate was 22.8 ml/hr-mm.
The water permeation rate after refluxing the 1% bovine serum albumin aqueous solution, which was then measured according to the method of Example 2, was 8.2 ml/Ilr =
The retention rate was 36% at mmHg・Tl12.

Example 5 Acrylonitrile '5951J and methoxypolyethylene glycol methacrylate-1~"M-100G"1'05
ger) Add 3,5 Mkl of MSO and add A as a 2-polymerization initiator.
DVN4.36CI was added and "M-" was added in the same manner as in Example 3.
100G" copolymerized polyacrylonitrile was obtained. The content of polyethylene oxide units in the copolymer was 14%.
120 g of the IC5 colloid was dissolved in DMSO480Q under stirring for 8 hours at 70'CT'' to obtain a homogeneous and transparent spinning stock solution.The viscosity of the stock solution was 163 voices at 70°C.

Using the same spinning device as in Example 1, a) while injecting nitrogen gas from the hollow nozzle, the discharge rate of the spinning stock solution was set to 0.7;
It was discharged at 0 g/min. The length of the dry part is 5 (1
) After passing through a coagulation bath consisting of a 16% DMSO aqueous solution at 52° C., it was washed with water, heat treated, and wound up at a speed of 19 m/Illth). b) Again.

Using n-octane as the injection fluid, the discharge rate was 1.0.
Sampling was carried out under similar conditions.

The quality and performance of the obtained hollow fibers were as follows.

Inner diameter/membrane W in the table: μ Water permeation rate: ml/1tr-mmt-1(+ ・t
Before n2: 1% albumin water j? Before and after flow: The rejection rate of albumin after flow was both 99.8% or more, indicating extremely high permselectivity.

Patent applicant Higashi Shikikai Co., Ltd.

Claims (1)

[Claims] A monomer having a polyethylene oxide unit of 5 or more and a polymerizable carbon-carbon double bond in the same molecule, JJ, and a monomer having a polymerizable carbon-carbon double bond A permselective hollow NJAta containing at least one component of a copolymer.