GO / PAN composite film preparation method

Abstract

The invention discloses a preparation method of a GO / PAN composite film. The preparation method comprises the following steps: a) preparing raw materials; b) preparing equipment; c) dispersing GO; d) a polymerization stage; step e) solution treatment; f) forming a film; step g) post-processing; h) performance testing; step i) analyzing a result; the preparation method comprises the following steps: a) raw material preparation: firstly, preparing graphene oxide, a polyacrylonitrile monomer and a solvent, and then ensuring that the graphene oxide, the polyacrylonitrile monomer and the solvent have good dispersity; the preparation of the GO / PAN composite membrane changes a traditional multi-layer assembly mode, a polymerization method is adopted for preparation, the phenomenon of poor dispersity is avoided in the preparation process, the situation that the quality of the composite membrane cannot be guaranteed is avoided, the dosage of GO cannot be regulated and controlled is avoided, and the situation that the structure and performance of the composite membrane cannot be controlled is avoided. The problems that the quality of the composite membrane cannot be guaranteed due to poor uniformity and dispersity of GO, and the structure and the performance of the composite membrane cannot be controlled due to the fact that the dosage of GO cannot be regulated and controlled are solved.

Description

Technical Field

[0001] The invention relates to the technical field of GO / PAN composite membranes, in particular to a method for preparing a GO / PAN composite membrane. Background Art

[0002] According to the patents published on the China Patent Network, the patent name is: A MoS2 / GO / CA composite membrane and its preparation method, the patent application number is: 201910547983.3, including the following steps: preparation of GO dispersion, preparation of MoS2 nanosheet dispersion and preparation of MoS2 / GO / CA composite membrane; the method is simple, the interlayer stability of the prepared composite membrane is greatly enhanced, the stability in aqueous solution is significantly improved, the pure water flux is greatly improved, and the retention rate of organic molecules and heavy metal ions is high; a MoS2 / GO / CA composite membrane, by intercalating molybdenum disulfide, successfully constructs a stable layered nanostructured composite membrane, the structure of the composite membrane is stable, and the performance is good; however, the above-mentioned preparation method has poor uniform dispersion of GO, which leads to the quality of the composite membrane cannot be guaranteed, and the amount of GO cannot be adjusted, resulting in the inability to control the structure and performance of the composite membrane.

[0003] Therefore, the preparation method needs to be redesigned to effectively prevent the phenomenon that the uniform dispersion of GO is poor and affects the quality of the composite membrane. Summary of the invention

[0004] In order to solve the problems raised in the above background technology, the purpose of the present invention is to provide a method for preparing a GO / PAN composite membrane, which has the advantages of being able to evenly disperse GO and control the amount of GO, thereby solving the problem that the poor uniform dispersion of GO affects the quality of the composite membrane.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for preparing a GO / PAN composite membrane, comprising the steps of a) raw material preparation; b) equipment preparation; c) GO dispersion; d) polymerization stage; e) solution treatment; f) membrane formation; g) post-treatment; h) performance testing; i) result analysis;

[0006] Step a) Raw material preparation: First, prepare graphene oxide, polyacrylonitrile monomer and solvent, then ensure that they have good dispersibility, and prepare an appropriate amount, select high-quality PAN monomer to ensure the smooth progress of the polymerization reaction, and the solvent is usually selected from dimethyl sulfoxide (DMSO) and the like to dissolve the PAN monomer and disperse GO;

[0007] Step b) Equipment preparation: prepare a reaction vessel, a stirring device and a temperature control device. The reaction vessel is a three-necked flask, etc., for the polymerization reaction. The stirring device is a magnetic stirrer, which is used to ensure the uniform dispersion of GO in the solvent and the sufficient mixing during the polymerization process. The temperature control device is a heating jacket, a cooling water circulation device, etc., which is used to accurately control the temperature of the polymerization reaction;

[0008] Step c) GO dispersion: adding an appropriate amount of GO into the solvent and stirring it thoroughly using a stirring device to ensure that GO is evenly dispersed in the solvent;

[0009] Step d) polymerization stage: add an appropriate amount of PAN monomer to the GO dispersion and continue stirring and mixing, then add an appropriate amount of initiator (such as dibenzoyl peroxide, etc.), and control the temperature and stirring speed of the reaction system to initiate the polymerization reaction of the PAN monomer. During the polymerization reaction, GO will be uniformly dispersed in the PAN matrix as a nanofiller;

[0010] Step e) solution treatment: After the polymerization reaction is completed, the obtained GO / PAN polymer solution is filtered and degassed to remove impurities and bubbles;

[0011] Step f) film formation: pouring the treated GO / PAN polymer solution into a suitable mold and controlling the film forming conditions (such as temperature, humidity, etc.) to form a flat and uniform composite film;

[0012] Step g) post-treatment: After the film is formed, drying and curing treatment can be performed to improve the strength and stability of the composite film;

[0013] Step h) Performance testing: The prepared GO / PAN composite membrane is subjected to performance testing, including separation performance, mechanical properties, thermal stability, etc., and then the structure of the composite membrane can be characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction;

[0014] Step i) Result analysis: Based on the performance test and characterization results, the performance characteristics of the composite membrane and the effect of GO on the PAN matrix were analyzed.

[0015] As a preferred embodiment of the present invention, the raw materials need to be sorted in a sterile environment during preparation, and each raw material needs to be mixed according to a proportion.

[0016] As a preferred embodiment of the present invention, the dispersibility of GO can be further improved by ultrasonic treatment or the like when the GO is dispersed.

[0017] As preferred in the present invention, during the polymerization stage, care should be taken to avoid excessively high temperatures that may lead to decomposition of PAN monomers or agglomeration of GO.

[0018] As a preferred embodiment of the present invention, the film can be obtained by using a scraper method or a casting method.

[0019] As preferred in the present invention, the stirring time of the GO dispersion should be appropriately extended by 1 to 2 minutes during the stirring process to ensure its uniform dispersion.

[0020] As preferred in the present invention, the GO dispersion should ensure the purity of the raw materials during the stirring process to avoid the entry of external impurities.

[0021] As a preferred embodiment of the present invention, during the polymerization stage, the progress of the polymerization reaction and the structure of the composite membrane can be controlled by adjusting parameters such as temperature, stirring speed and reaction time.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The GO / PAN composite membrane preparation of the present invention changes the traditional multi-layer assembly method and adopts the polymerization method for preparation. The preparation process will not have the phenomenon of poor dispersion, nor will it lead to the quality of the composite membrane being unguaranteed, nor will it be impossible to adjust the amount of GO, and will not lead to the inability to control the structure and performance of the composite membrane. It solves the problem that the uniform dispersion of GO is poor, resulting in the quality of the composite membrane being unguaranteed, the amount of GO being unregulated, and the structure and performance of the composite membrane being uncontrollable. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] The present invention provides a method for preparing a GO / PAN composite membrane, comprising the steps of a) raw material preparation; b) equipment preparation; c) GO dispersion; d) polymerization stage; e) solution treatment; f) membrane formation; g) post-treatment; h) performance testing; i) result analysis;

[0026] Step a) Raw material preparation: First, prepare graphene oxide, polyacrylonitrile monomer and solvent, then ensure that they have good dispersibility, and prepare an appropriate amount, select high-quality PAN monomer to ensure the smooth progress of the polymerization reaction, and the solvent is usually selected from dimethyl sulfoxide (DMSO) and the like to dissolve the PAN monomer and disperse GO;

[0027] Step b) Equipment preparation: prepare a reaction vessel, a stirring device and a temperature control device. The reaction vessel is a three-necked flask, etc., for the polymerization reaction. The stirring device is a magnetic stirrer, which is used to ensure the uniform dispersion of GO in the solvent and the sufficient mixing during the polymerization process. The temperature control device is a heating jacket, a cooling water circulation device, etc., which is used to accurately control the temperature of the polymerization reaction;

[0028] Step c) GO dispersion: adding an appropriate amount of GO into the solvent and stirring it thoroughly using a stirring device to ensure that GO is evenly dispersed in the solvent;

[0029] Step d) polymerization stage: add an appropriate amount of PAN monomer to the GO dispersion and continue stirring and mixing, then add an appropriate amount of initiator (such as dibenzoyl peroxide, etc.), and control the temperature and stirring speed of the reaction system to initiate the polymerization reaction of the PAN monomer. During the polymerization reaction, GO will be uniformly dispersed in the PAN matrix as a nanofiller;

[0030] Step e) solution treatment: After the polymerization reaction is completed, the obtained GO / PAN polymer solution is filtered and degassed to remove impurities and bubbles;

[0031] Step f) film formation: pouring the treated GO / PAN polymer solution into a suitable mold and controlling the film forming conditions (such as temperature, humidity, etc.) to form a flat and uniform composite film;

[0032] Step g) post-treatment: After the film is formed, drying and curing treatment can be performed to improve the strength and stability of the composite film;

[0033] Step h) Performance testing: The prepared GO / PAN composite membrane is subjected to performance testing, including separation performance, mechanical properties, thermal stability, etc., and then the structure of the composite membrane can be characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction;

[0034] Step i) Result analysis: Based on the performance test and characterization results, the performance characteristics of the composite membrane and the effect of GO on the PAN matrix were analyzed.

[0035] The present invention is further configured such that raw materials need to be sorted in a sterile environment during preparation, and each raw material needs to be mixed according to a proportion.

[0036] The present invention is further configured that when GO is dispersed, the dispersibility of GO can be further improved by methods such as ultrasonic treatment.

[0037] The present invention is further configured that during the polymerization stage, care should be taken to avoid excessively high temperatures that may lead to decomposition of PAN monomers or agglomeration of GO.

[0038] The present invention is further configured such that when forming the film, a scraper method or a casting method can be used to obtain the film.

[0039] The present invention is further configured that, during the stirring process of GO dispersion, the stirring time should be appropriately extended by 1 to 2 minutes to ensure its uniform dispersion.

[0040] The present invention is further configured such that during the stirring process of GO dispersion, the purity of the raw materials should be ensured to prevent the entry of external impurities.

[0041] The present invention is further configured such that during the polymerization stage, the progress of the polymerization reaction and the structure of the composite membrane can be controlled by adjusting parameters such as temperature, stirring speed and reaction time.

[0042] The working principle and use process of the present invention are as follows: first, graphene oxide, polyacrylonitrile monomer and solvent are prepared, and then they are ensured to have good dispersibility, and an appropriate amount is prepared, and high-quality PAN monomer is selected to ensure the smooth progress of the polymerization reaction. The solvent is usually selected from dimethyl sulfoxide (DMSO) and the like, which is used to dissolve the PAN monomer and disperse GO. Then a reaction container, a stirring device and a temperature control device are prepared. The reaction container is selected from a three-necked flask and the like, which is used for the polymerization reaction. Then the stirring device is selected from a magnetic stirrer to ensure the uniform dispersion of GO in the solvent and sufficient mixing during the polymerization process. The temperature control device is selected from a heating jacket, a cooling water circulation device, etc., which is used to accurately control the temperature of the polymerization reaction. Then an appropriate amount of GO is added to the solvent, and the stirring device is used to fully stir to ensure the uniform dispersion of GO in the solvent. An appropriate amount of PAN monomer is added to the GO dispersion, and stirring and mixing is continued. Then an appropriate amount of initiator (such as dibenzoyl peroxide, etc.) is added, and the temperature is controlled. The temperature and stirring speed of the reaction system are controlled to initiate the polymerization reaction of PAN monomer. During the polymerization reaction, GO will be uniformly dispersed in the PAN matrix as a nanofiller. After the polymerization reaction is completed, the obtained GO / PAN polymer solution is filtered and degassed to remove impurities and bubbles. The treated GO / PAN polymer solution is poured into an appropriate mold, and the film-forming conditions (such as temperature, humidity, etc.) are controlled to form a flat and uniform composite membrane. After film formation, drying and curing treatments can be performed to improve the strength and stability of the composite membrane. The prepared GO / PAN composite membrane is then subjected to performance tests, including separation performance, mechanical properties, thermal stability, etc., and then the structure of the composite membrane can be characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. Then, based on the performance test and characterization results, the performance characteristics of the composite membrane and the influence of GO on the PAN matrix are analyzed, so that the GO can be uniformly dispersed and the amount of GO can be controlled.

[0043] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0044] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a GO / PAN composite membrane, characterized in that: The method comprises the steps of a) raw material preparation, b) equipment preparation, c) GO dispersion, d) polymerization stage, e) solution treatment, f) film formation, g) post-treatment, h) performance testing, and i) result analysis. Step a) Raw material preparation: First, prepare graphene oxide, polyacrylonitrile monomer and solvent, then ensure that they have good dispersibility, and prepare an appropriate amount, select high-quality PAN monomer to ensure the smooth progress of the polymerization reaction, and the solvent is usually selected from dimethyl sulfoxide (DMSO) and the like to dissolve the PAN monomer and disperse GO; Step b) Equipment preparation: prepare a reaction vessel, a stirring device and a temperature control device. The reaction vessel is a three-necked flask, etc., for the polymerization reaction. The stirring device is a magnetic stirrer, which is used to ensure the uniform dispersion of GO in the solvent and the sufficient mixing during the polymerization process. The temperature control device is a heating jacket, a cooling water circulation device, etc., which is used to accurately control the temperature of the polymerization reaction; Step c) GO dispersion: adding an appropriate amount of GO into the solvent and stirring it thoroughly using a stirring device to ensure that GO is evenly dispersed in the solvent; Step d) polymerization stage: add an appropriate amount of PAN monomer to the GO dispersion and continue stirring and mixing, then add an appropriate amount of initiator (such as dibenzoyl peroxide, etc.), and control the temperature and stirring speed of the reaction system to initiate the polymerization reaction of the PAN monomer. During the polymerization reaction, GO will be uniformly dispersed in the PAN matrix as a nanofiller; Step e) solution treatment: After the polymerization reaction is completed, the obtained GO / PAN polymer solution is filtered and degassed to remove impurities and bubbles; Step f) film formation: pouring the treated GO / PAN polymer solution into a suitable mold and controlling the film forming conditions (such as temperature, humidity, etc.) to form a flat and uniform composite film; Step g) post-treatment: After the film is formed, drying and curing treatment can be performed to improve the strength and stability of the composite film; Step h) Performance testing: The prepared GO / PAN composite membrane is subjected to performance testing, including separation performance, mechanical properties, thermal stability, etc., and then the structure of the composite membrane can be characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction; Step i) Result analysis: Based on the performance test and characterization results, the performance characteristics of the composite membrane and the effect of GO on the PAN matrix were analyzed.

2. The method for preparing a GO / PAN composite membrane according to claim 1, characterized in that: The raw materials need to be sorted in a sterile environment during preparation, and each raw material needs to be mixed according to the proportion.

3. The method for preparing a GO / PAN composite membrane according to claim 1, characterized in that: When the GO is dispersed, the dispersibility of GO can be further improved by ultrasonic treatment or the like.

4. The method for preparing a GO / PAN composite membrane according to claim 1, characterized in that: During the polymerization stage, care should be taken to avoid excessively high temperatures that may lead to decomposition of PAN monomers or agglomeration of GO.

5. The method for preparing a GO / PAN composite membrane according to claim 1, characterized in that: The film can be formed by a scraper method or a casting method.

6. The method for preparing a GO / PAN composite membrane according to claim 1, characterized in that: The stirring time of the GO dispersion should be appropriately extended by 1 to 2 minutes during the stirring process to ensure its uniform dispersion.

7. The method for preparing a GO / PAN composite membrane according to claim 1, characterized in that: The GO dispersion should ensure the purity of the raw materials during the stirring process to prevent the entry of external impurities.

8. The method for preparing a GO / PAN composite membrane according to claim 1, characterized in that: During the polymerization stage, the progress of the polymerization reaction and the structure of the composite membrane can be controlled by adjusting parameters such as temperature, stirring speed and reaction time.