阅读说明：本技术 一种高稳定性血液透析膜及其制备方法 (High-stability hemodialysis membrane and preparation method thereof ) 是由 汪勇 钟丁磊 于 2019-09-27 设计创作，主要内容包括：本发明提供一种高稳定性血液透析膜,它是仅以聚砜基两亲嵌段共聚物为成膜材料制备铸膜液、经相转化法制备得到的血液透析膜；聚砜基两亲嵌段共聚物分子量在20～240kDa之间,其中,聚砜嵌段和亲水嵌段的质量比在2.4～8.2之间。本发明还提供制备高稳定性血液透析膜的方法,包括：将聚砜基两亲嵌段共聚物制备铸膜液并采用溶液相转化法制膜,得到高稳定性的血液透析膜；聚砜基两亲嵌段共聚物分子量在20～240kDa之间,且聚砜嵌段和亲水嵌段的质量比在2.4～8.2之间。本发明的血液透析膜不仅对中小型分子毒素都有良好的透过性能,而且能够完全杜绝溶出,具有永久的亲水性。本发明的制备方法工艺简单,且无需使用任何添加剂,从根本上解决了血液透析膜使用过程中出现溶出物的问题。(The invention provides a high-stability hemodialysis membrane, which is a hemodialysis membrane prepared by preparing a membrane casting solution by only taking a polysulfone-based amphiphilic block copolymer as a membrane forming material and performing a phase inversion method; the molecular weight of the polysulfone-based amphiphilic block copolymer is between 20 and 240kDa, wherein the mass ratio of the polysulfone block to the hydrophilic block is between 2.4 and 8.2. The present invention also provides a method for preparing a high stability hemodialysis membrane, comprising: preparing a membrane casting solution from the polysulfone-based amphiphilic block copolymer and preparing a membrane by adopting a solution phase conversion method to obtain a high-stability hemodialysis membrane; the molecular weight of the polysulfone-based amphiphilic block copolymer is between 20 and 240kDa, and the mass ratio of the polysulfone block to the hydrophilic block is between 2.4 and 8.2. The hemodialysis membrane of the invention not only has good permeability to middle and small molecular toxins, but also can completely stop dissolution and has permanent hydrophilicity. The preparation method of the invention has simple process, does not need to use any additive, and fundamentally solves the problem of the dissolved substance in the use process of the hemodialysis membrane.)

1. A high stability hemodialysis membrane, characterized in that: the method is to prepare a membrane casting solution by only taking a polysulfone-based amphiphilic block copolymer as a membrane forming material and prepare a hemodialysis membrane by a phase inversion method; the molecular weight of the polysulfone-based amphiphilic block copolymer is between 20 and 240kDa, wherein the mass ratio of the polysulfone block to the hydrophilic block is between 2.4 and 8.2.

2. The hemodialysis membrane of claim 1, wherein: the polysulfone block is selected from any one or more of bisphenol A PSF, polyarylsulfone or polyethersulfone, and the hydrophilic block is a polyethylene glycol (PEG) block; namely, the polysulfone-based amphiphilic block copolymer is a polysulfone-polyethylene glycol block copolymer.

3. The hemodialysis membrane of claim 2, wherein: the molecular weight of the polysulfone polyethylene glycol block copolymer is 68-182 kDa; preferably between 95 and 96 kDa.

4. The hemodialysis membrane of any one of claims 2 and 3, wherein: in the polysulfone-polyethylene glycol block copolymer, the mass ratio of the polysulfone block to the polyethylene glycol block is 3-4, preferably 3.7-3.8.

5. A method of preparing a high stability hemodialysis membrane, comprising the steps of: preparing a membrane casting solution from the polysulfone-based amphiphilic block copolymer, and preparing a membrane by adopting a solution phase inversion method to obtain a high-stability hemodialysis membrane; the molecular weight of the polysulfone-based amphiphilic block copolymer is 20-240 kDa, and the mass ratio of the polysulfone block to the hydrophilic block is 2.4-8.2.

6. The method of claim 5, wherein: the polysulfone block is selected from any one or more of bisphenol A PSF, polyarylsulfone or polyethersulfone, and the hydrophilic block is a polyethylene glycol (PEG) block; namely, the polysulfone-based amphiphilic block copolymer is a polysulfone-polyethylene glycol block copolymer.

7. The method of claim 6, wherein: the molecular weight of the polysulfone polyethylene glycol block copolymer is 68-182 kDa; preferably between 95 and 96 kDa.

8. The method of any one of claims 6 or 7, wherein: in the polysulfone-polyethylene glycol block copolymer, the mass ratio of the polysulfone block to the polyethylene glycol block is 3-4, preferably 3.7-3.8.

9. The method of claim 8, characterized by the specific steps of:

1) preparation of membrane casting liquid by using polysulfone polyethylene glycol block copolymer

Dissolving the polysulfone-polyethylene glycol block copolymer in a membrane casting solution solvent, heating, mechanically stirring and dissolving, standing and degassing to obtain a clear membrane casting solution with good dissolution;

2) film making process

Uniformly coating the casting solution obtained in the step 1) on a clean glass plate through a film scraper, volatilizing the solvent of the casting solution in air, immediately immersing the glass plate into a coagulating bath for phase conversion to obtain the amphiphilic polysulfone-polyethylene glycol block copolymer hemodialysis membrane, taking out the membrane, and then placing the membrane in deionized water for immersion.

10. The method of claim 9, wherein: 1) the casting solution solvent is one of N, N-dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone, and most preferably N-methylpyrrolidone.

11. The method of claim 9, wherein: 2) the mass proportion of the polysulfone-polyethylene glycol block copolymer dissolved in the membrane casting solution solvent is 17 wt% -25 wt%, and the most preferable proportion is 21 wt%.

Technical Field

The invention belongs to the technical field of porous material separation membranes, and particularly relates to a hemodialysis membrane and a method for preparing the hemodialysis membrane by using a polysulfone block copolymer.

Background

Hemodialysis techniques are an important modality of renal replacement therapy for patients with acute and chronic renal failure. The process comprises the steps of draining blood in a human body to the outside of the body, purifying the blood through a dialyzer, and refluxing the purified blood. Hemodialysis finds widespread application in hemodialysis and blood purification techniques due to its relatively low cost and low therapeutic requirements. In addition, since it is an in vitro process, it can reduce the occurrence of side effects. Hemodialysis membranes are among the most important components in the overall process. Therefore, a simple and efficient method for preparing a hemodialysis membrane is very important.

Polysulfone is a commonly used material for preparing hemodialysis membranes, but because of its strong hydrophobicity, polysulfone has a problem of poor blood compatibility, resulting in the generation of blood coagulation and even thrombus. At present, hydrophilic additives or complex modification means are often used in the practical application process to improve the hydrophilicity and blood compatibility of polysulfone. Although the additive can improve the hydrophilicity and blood compatibility of the polysulfone, the additive is only modified by simple blending and can gradually run off in the using process, so that the performance is reduced, and even side effects are generated; the performance can be maintained for a long time by other complicated modification means, but the complexity of the process causes the difficulty in large-scale production, and the production cost of the hemodialysis membrane is increased.

Patent document CN201610125548 discloses a method for preparing a hemodialysis membrane, which uses polysulfone as a main membrane forming material, and uses polysulfone/polyethylene glycol block copolymer as a pore-forming agent to promote the formation of membrane pores, and fix the pore-forming agent on the surface of a polysulfone-based membrane, thereby improving the hydrophilicity, membrane flux, flux recovery rate and stability of the membrane. In the scheme, although the polysulfone and the polysulfone/polyethylene glycol block copolymer have good compatibility and can reduce the dissolution phenomenon of the polysulfone/polyethylene glycol block copolymer, the film-forming main material and the pore-forming agent are still two structurally independent substances, so the dissolution phenomenon cannot be completely avoided, and the stability of the hemodialysis membrane prepared by the method still needs to be improved.

Therefore, there is still a need in the art to develop a hemodialysis membrane with improved stability, and a new method for preparing a hemodialysis membrane with high stability.

Disclosure of Invention

In order to overcome the defects and shortcomings of the prior art, the invention aims to provide a high-stability hemodialysis membrane which has good permeability to middle and small molecular toxins, can completely prevent dissolution and has permanent hydrophilicity.

The invention also aims to provide a method for preparing the high-stability hemodialysis membrane, which has the advantages that the preparation process is simpler than the prior process, no additive is needed in the whole process, the prepared hemodialysis membrane has permanent hydrophilicity and has good permeability for middle and small molecular toxins, and the problem of dissolved substances in the use process of the hemodialysis membrane is fundamentally solved.

The technical scheme for realizing the aim of the invention is as follows:

firstly, providing a hemodialysis membrane, which is prepared by preparing a membrane casting solution only by taking a polysulfone-based amphiphilic block copolymer as a membrane forming material and preparing the hemodialysis membrane by a phase inversion method; the molecular weight of the polysulfone-based amphiphilic block copolymer is between 20 and 240kDa, wherein the mass ratio of the polysulfone block to the hydrophilic block is between 2.4 and 8.2.

In the hemodialysis membrane, the polysulfone block is preferably selected from one or more of bisphenol A PSF, polyarylsulfone or polyethersulfone; the hydrophilic block can be a plurality of existing hydrophilic materials which can form a block copolymer with polysulfone; preferred hydrophilic blocks of the present invention are polyethylene glycol (PEG) blocks.

In the scheme of the invention, the molecular weight of the polysulfone-based amphiphilic block copolymer and the mass ratio of the polysulfone block and the hydrophilic block have influence on the comprehensive performance of the hemodialysis membrane. When the molecular weight of the polysulfone-based amphiphilic block copolymer is too low or the mass ratio of the polysulfone block to the hydrophilic block is too low, the polysulfone-based amphiphilic block copolymer is difficult to form a film or has poor mechanical properties after the film is formed; and when the molecular weight of the polysulfone-based amphiphilic block copolymer is too high or the mass ratio of the polysulfone block to the hydrophilic block is too high, the prepared blood permeable membrane has poor permeation and separation performance.

In a further preferable hemodialysis membrane, the molecular weight of the polysulfone polyethylene glycol block copolymer is 68-182 kDa; more preferably between 95 and 96 kDa.

In a further preferred hemodialysis membrane of the present invention, in the polysulfone-polyethylene glycol block copolymer, the mass ratio of the polysulfone block to the polyethylene glycol block is 3 to 4, and most preferably 3.7 to 3.8.

In addition, the present invention also provides a method for preparing a high-stability hemodialysis membrane, comprising the steps of: preparing a membrane casting solution from the polysulfone-based amphiphilic block copolymer and preparing a membrane by adopting a solution phase conversion method to obtain a high-stability hemodialysis membrane; (ii) a The molecular weight of the polysulfone-based amphiphilic block copolymer is 20-240 kDa, and the mass ratio of the polysulfone block to the hydrophilic block is 2.4-8.2.

In the preparation scheme of the invention, the hemodialysis membranes with different performances or strengths can be prepared by selecting the polysulfone-based amphiphilic block copolymers with different molecular weights or selecting the polysulfone-based amphiphilic block copolymers with different mass ratios between blocks.

In the method for preparing the high-stability hemodialysis membrane, the polysulfone block can be selected from any one or more of bisphenol A PSF, polyarylsulfone or polyethersulfone, and the hydrophilic block is polyethylene glycol (PEG); namely, the polysulfone-based amphiphilic block copolymer is a polysulfone-polyethylene glycol block copolymer.

In the further preferable method for preparing the high-stability hemodialysis membrane, the molecular weight of the polysulfone polyethylene glycol block copolymer is 68-182 kDa; more preferably between 95 and 96 kDa. In a further preferred method, in the polysulfone polyethylene glycol block copolymer with the molecular weight, the mass ratio of the polysulfone block to the polyethylene glycol block is 3-4, and most preferably 3.7-3.8.

In a preferred embodiment of the present invention, the method for preparing a high-stability hemodialysis membrane comprises the following steps:

1) preparation of membrane casting liquid by using polysulfone polyethylene glycol block copolymer

Dissolving the polysulfone-polyethylene glycol block copolymer in a membrane casting solution solvent, heating, mechanically stirring and dissolving, standing and degassing to obtain a clear membrane casting solution with good dissolution;

2) film making process

Uniformly coating the casting solution obtained in the step 1) on a clean glass plate through a film scraper, volatilizing the solvent of the casting solution in air, immediately immersing the glass plate into a coagulating bath for phase conversion to obtain the amphiphilic polysulfone-polyethylene glycol block copolymer hemodialysis membrane, taking out the membrane, and then placing the membrane in deionized water for immersion.

In a further preferred embodiment of the present invention, the casting solution solvent in step 1) may be one selected from N, N-dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone, and most preferably N-methylpyrrolidone.

In a further preferred embodiment of the present invention, the polysulfone-polyethylene glycol block copolymer dissolved in the membrane casting solution solvent in step 1) is 17 wt% to 25 wt%, and the most preferred ratio is 21 wt%.

In a further preferable embodiment of the present invention, the time for volatilizing the casting solution solvent in step 2) is 5 to 60 seconds.

In a further preferable scheme of the invention, the coagulating bath in the step 2) is one or a mixture of water, methanol or ethanol.

Compared with the prior art, the invention has the following beneficial technical effects:

(1) only the polysulfone-based amphiphilic block copolymer is used for preparing the membrane, and the problems of dialysis membrane loss and preparation cost are solved simultaneously

Detailed Description

The present invention will be further explained with reference to examples. The following examples are provided only for illustrating the present invention and are not intended to limit the scope of the present invention.