A method for preparing modified graphene oxide for textile finishing agents

Abstract

This invention provides a method for preparing modified graphene oxide for textile finishing agents, belonging to the field of graphene new material technology. The method includes: connecting a graphene oxide film to a cathode electrode; using an alkaline electrochemical solution obtained by mixing a cationic modifier and a conductivity enhancer as the electrolyte; subjecting the mixture to pulsed electrochemical treatment; and obtaining the modified graphene oxide after post-treatment. Compared to traditional long-duration, high-temperature, and high-pressure reactions, this invention employs a DC pulsed electrochemical treatment process. By adjusting parameters such as current density, on / off time, and pulse frequency, the stability of the cationic grafting in the product is effectively improved, while simultaneously improving surface quality, without oxidizing the graphene and destroying its original basic structure, thus increasing the efficiency of the electrochemical treatment.

Description

Technical Field

[0001] This invention belongs to the field of graphene new material technology, and particularly relates to a method for preparing modified graphene oxide for textile finishing agents. Background Technology

[0002] In recent years, people's demand for textiles has expanded beyond everyday wear and home decoration, placing higher demands on their functionality. Besides fulfilling their basic value during use, textiles must also possess one or more functions such as conductivity, UV protection, flame retardancy, hydrophobicity, and health benefits. The textile industry involves multiple processing stages, including spinning, weaving, and dyeing. Different types of auxiliary chemicals are needed to improve textile quality, enhance processing effects, increase production efficiency, simplify processes, reduce production costs, and endow textiles with various superior application properties, all tailored to the characteristics of different fibers. These chemicals are collectively referred to as textile finishing agents. Most textile finishing agents on the market are cationic surfactants. As early as 1896, F. Kraft et al. discovered that hexadecylamine hydrochloride possessed soap-like foaming properties. Since 1928, cationic surfactants have been used industrially, such as as fiber softeners, antistatic agents, hydrophobic agents, dyeing auxiliaries, emulsifiers, and wetting agents, exhibiting certain anti-corrosion properties.

[0003] Graphene materials are widely used in the textile industry due to their excellent electrical, optical, thermal, and mechanical properties. Graphene oxide, an oxide of graphene, possesses active groups and water solubility, resulting in stronger reactivity and making it more convenient to use than graphene under certain special conditions. As a single-layer material exfoliated from graphene oxide, graphene oxide is stable in aqueous solutions and polar solvents due to the introduction of numerous oxygen-containing groups on its surface and edges, but it rapidly aggregates in cationic solvents. Therefore, to fully utilize the functions of graphene oxide in the textile industry, it is necessary to modify it without destroying its original nanostructure to ensure stable dispersion in most textile finishing agents.

[0004] Existing invention patent CN115726190A describes a method to enhance the conductivity of fabrics by first modifying cotton fabric with filaments and cations, then combining it with graphene oxide and reducing it to ultimately prepare reduced graphene oxide / cationically modified cotton fabric. This method modifies the raw material fabric, which can damage other properties of the fabric. Furthermore, the process involves large amounts of caustic soda and heating steps, making industrialization complex and posing a risk of toxicity to humans. Therefore, modifying the additive graphene oxide is currently the mainstream approach. Invention patent CN115039769A describes a cationically modified graphene antibacterial spray and its preparation method, which mainly improves antibacterial properties through the synergistic effect of modified graphene and silver ions. However, this process is complex and costly, making it unsuitable for industrialization in the textile industry. Moreover, both of these inventions damage the basic structure of graphene oxide, reducing its other excellent properties. The invention patent CN11586034A mentions a method for preparing quaternary ammonium salt group graphene oxide materials, which includes two complex steps: tertiary amination modification and quaternary amination modification. The process requires a long-term high-temperature reaction, and the reagents are toxic to the human body.

[0005] Therefore, achieving low-cost, efficient, and safe preparation of a modified graphene oxide suitable for textile finishing agents without damaging the original structure of graphene oxide has broad prospects.

[0006] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0007] To address the technical problems of complex and highly toxic methods for modifying graphene oxide used in the textile industry, which can also damage the structure of graphene oxide, a method for preparing modified graphene oxide for textile finishing agents is provided.

[0008] The first aspect of this invention provides a method for preparing modified graphene oxide for textile finishing agents. The method involves connecting a graphene oxide film to a cathode electrode, using an alkaline electrochemical solution obtained by mixing a cationic modifier and a conductivity enhancer as the electrolyte, and subjecting the mixture to pulsed electrochemical treatment. After post-treatment, the modified graphene oxide is obtained. During the electrochemical process, the graphene oxide undergoes an intercalation reaction via cations; therefore, the graphene oxide film can only be connected to the cathode electrode, such as by clamping it to the cathode, and cannot be clamped to the anode. Both the cathode and anode electrodes can be platinum electrodes.

[0009] In some embodiments, the preparation method of the graphene oxide film includes: filtering a graphene oxide dispersion of 1-1.5 mg / ml, and the resulting graphene oxide filter cake is the graphene oxide film. Excessively high concentrations will result in poor dispersion of graphene oxide powder in aqueous solution. Auxiliary dispersion tools include magnetic stirrers or electric stirrers, and dispersion should be carried out for more than 1 hour. Ultrasonic machines should not be used, otherwise, excessive power will cause defects and damage to the graphene oxide sheets.

[0010] In some embodiments, the water content of the graphene oxide filter cake is 30%-70%. In this state, the graphene oxide can be peeled off as a film.

[0011] In some embodiments, the cationic modifier is one or more of the following: dodecyl dimethyl benzyl ammonium bromide, dodecyl dimethyl phenoxyethyl ammonium bromide, dialkyl dimethyl ammonium chloride, dialcyl ammonium chloride, n-alkyl dimethyl benzyl ammonium chloride, dodecyl trimethyl ammonium chloride, dodecyl dimethyl benzyl ammonium chloride, didodecyl dimethyl ammonium chloride, and hexadecyl trimethyl ammonium bromide.

[0012] In some embodiments, the conductivity enhancer is one or more of potassium nitrate, sodium nitrate, ammonium nitrate, ammonium persulfate, ammonium sulfate, potassium persulfate, potassium sulfate, sodium persulfate, and sodium sulfate.

[0013] In some embodiments, the electrochemical solution is formulated as a 1:1 mixture of 45 mmol / L-55 mmol / L cationic modifier and 0.5 mol / L-0.6 mol / L conductivity enhancer.

[0014] And / or, the pH of the electrochemical solution is 8-9. This is adjusted by adding small amounts of 0.05 mol / L NaOH solution multiple times.

[0015] In some embodiments, the conditions for the pulsed electrochemical treatment include: a pulsed current of 600mA-900mA / g applied per unit mass, a pulse period of 100ms, a pulse signal duration of 30ms-80ms, and a total pulse time of 10-15min. Samples obtained within this electrolysis parameter range meet the required quality standards. Setting the current too high or the pulse signal duration too long can lead to an overly vigorous reaction, resulting in strong side reactions such as the generation of bubbles during the initial electrolysis of water. Conversely, setting the current too low or the pulse signal duration too short can prolong the reaction time, increasing the modification time cost and reducing efficiency.

[0016] In some embodiments, the post-treatment includes washing and drying. During washing, 1-3g of defoamer is added. The defoamer is one or more of polysiloxane, silicone emulsion, polyurethane, and polyacrylamide. Polyurethane and polyacrylamide are non-silicone defoamers. Since cationic modifiers typically significantly reduce the surface tension of water, leading to the generation of numerous bubbles during washing, a small amount of defoamer needs to be added during washing. The sample is first washed several times using a centrifuge, then cleaned using methods such as vacuum filtration and pressure filtration until no precipitate is formed in the final filtrate when tested with silver nitrate, indicating that the sample is clean.

[0017] In some embodiments, the drying temperature is 50°C-60°C, and the drying time is 6-8 hours. Preferably, the drying is carried out at a low temperature in a vacuum drying oven.

[0018] A second aspect of the present invention provides a modified graphene oxide, which is prepared by the above-described preparation method.

[0019] This invention uses graphene oxide as a starting material. Through DC pulse electrochemistry in a cationic modifier, adjusting the current density, on / off time, and pulse frequency, positively charged cationic groups are stably grafted onto the surface of the graphene oxide. Simultaneously, the original sheet-like nanostructure of the modified graphene oxide is not significantly affected, preserving the excellent properties of sheet-like nanoparticles. The introduction of DC pulse electrochemistry significantly improves the efficiency and precision of the modification process compared to conventional DC electrochemistry. Ultimately, the modified graphene oxide product can be stably dispersed in textile finishing agents, giving the fabric superior antistatic, antibacterial, and thermal conductivity properties.

[0020] DC pulse electrolysis refers to an electrolysis method in which a current of approximately 50% greater in intensity than direct current is simultaneously supplied to the electrolytic cell at the same time. DC pulse current electrolysis modification uses a DC pulse current instead of a traditional DC power supply, which can significantly improve the efficiency and precision of the modification. This is due to the following two reasons: First, the pulse intervals during pulse electrolysis facilitate the renewal of the electrolyte in the processing gap and allow for the full discharge of electrolysis products, gas evolution, and endothermic substances, resulting in a more uniform conductivity throughout the solution and effectively improving the electric field. Second, the instantaneous step of the pulse current generates a gas evolution pressure wave in the gap, which is equivalent to stirring the solution in the gap, thus improving the flow field.

[0021] Compared with existing technologies, the technical effects achieved by this invention are as follows:

[0022] (1) This invention employs a DC pulse electrochemical process: Compared to traditional long-term high-temperature and high-pressure reactions, this invention employs a DC pulse electrochemical treatment process. By adjusting parameters such as current density, on / off time, and pulse frequency, the stability of the cation grafting of the product is effectively improved, while the surface quality is also improved, without oxidizing graphene and destroying the original basic structure, thus improving the efficiency of electrochemical treatment.

[0023] (2) Preservation of the original nanostructure: This method successfully preserves the original sheet-like nanostructure of graphene oxide during the modification process, while stably grafting positively charged cationic groups onto its surface. This structural stability enables the modified graphene oxide to be stably dispersed in cationic textile finishing agents and to exhibit excellent antistatic, antibacterial, thermally conductive, and electrically conductive properties.

[0024] (3) Green and environmentally friendly: The steps required by this invention are electrochemical, which is efficient and energy-saving; the raw materials used are less toxic to the human body and have the characteristics of being green and environmentally friendly, which helps to protect the environment and human health.

[0025] (4) Low cost and high yield: The raw materials, such as graphene oxide, modifiers, and conductivity enhancers used are all inexpensive, resulting in very low preparation costs. In addition, the process of this invention is simple, safe, energy-efficient, and has a high yield, making it easy to achieve industrial-scale mass production.

[0026] (5) Multifunctional Applications: Modified graphene oxide exhibits excellent performance in textile finishing agents, providing textiles with reinforcement, antistatic, and conductive functions, bringing new opportunities for the development of the textile industry. Furthermore, this preparation method also shows promise in fields such as electronic devices and energy storage, contributing to technological advancements in multiple sectors, especially bringing unprecedented development opportunities to the textile industry and other related fields. Attached Figure Description

[0027] Figure 1 This is a comparison diagram of the dispersion of graphene oxide before and after modification in anti-dye paste over 24 hours in Example 1 of the present invention.

[0028] Figure 2 This is a comparison diagram of the dispersion of graphene oxide before and after modification in the fixing agent over 24 hours in Example 1 of the present invention.

[0029] Figure 3 This is a comparison diagram of the dispersion of graphene oxide before and after modification in ointment over 24 hours in Example 1 of the present invention.

[0030] Figure 4 This is an optical microscope image of the modified pre-graphene oxide in Example 2 of the present invention;

[0031] Figure 5This is an optical microscope image of the modified graphene oxide in Example 2 of the present invention;

[0032] Figure 6 The Fourier transform infrared spectrum of the modified graphene oxide in Example 3 of this invention;

[0033] Figure 7 This is a comparison diagram of the dispersion of graphene oxide before and after modification in anti-dye paste under DC conditions over 24 hours in the comparative example of this invention. Detailed Implementation

[0034] The technical solution of the present invention will be described below with reference to the accompanying drawings and specific embodiments. It should be understood that the one or more steps mentioned in the present invention do not preclude the existence of other methods and steps before or after the combined steps, or that other methods and steps may be inserted between these explicitly mentioned steps. It should also be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Unless otherwise stated, the numbering of each method step is only for the purpose of identifying each method step, and not for limiting the order of each method or limiting the scope of the present invention. Changes or adjustments to their relative relationships, without substantial changes to the technical content, can also be considered as within the scope of the present invention.

[0035] The raw materials and instruments used in the examples are not subject to any specific restrictions on their source; they can be purchased from the market or prepared according to conventional methods known to those skilled in the art.

[0036] Example 1

[0037] The experimental procedure is as follows: 500 ml of pure water was mixed with graphene oxide powder at a concentration of 0.1 mg / ml, and dispersed using a stirrer. The dispersed graphene oxide aqueous solution was filtered, and the filter cake on the filter membrane was collected for later use. 150 ml of a 1:1 mixture of 45 mmol / L dodecyltrimethylammonium chloride and 0.5 mol / L potassium sulfate was prepared as the electrochemical solution. 0.05 mol / L NaOH solution was added in small amounts several times until the pH of the solution stabilized at 8. Platinum electrodes were used for both the anode and cathode. The pulse current was set to 600 mA / g, the pulse period to 100 ms, the pulse signal duration to 30 ms-80 ms, and the total pulse time to 10 min. After the pulse electrochemical reaction, the electrochemical solution and sample were removed and washed three times by centrifugation, followed by six times by filtration. The sample was considered clean if no precipitate was formed in the filtrate after the final filtration, as determined by silver nitrate testing. 1 g of polysiloxane was added as an antifoaming agent before washing. Finally, the filter cake on the filter membrane was placed in a vacuum drying oven and dried at 50°C for 6 hours to obtain modified graphene oxide powder suitable for textile finishing agents.

[0038] The modified graphene oxide powders from this embodiment were dispersed in textile anti-dyeing paste auxiliaries, textile color-fixing agents, and textile softening oils, and the results are as follows: Figure 7 As shown. Figure 1 , Figure 2 and Figure 3 The images show the dispersion results of graphene oxide before and after modification in textile anti-dyeing paste auxiliaries, textile fixing agents, and textile softening oils after 24 hours. The left side represents before modification, and the right side represents after modification. The results indicate that the modified graphene oxide exhibits good dispersibility in cationic textile finishing agents and can maintain stable dispersion for a long time.

[0039] Example 2

[0040] The experimental procedure is as follows: 500 ml of pure water was mixed with graphene oxide powder at a concentration of 0.1 mg / ml, and dispersed using a stirrer. The dispersed graphene oxide aqueous solution was filtered, and the filter cake on the filter membrane was collected for later use. 150 ml of a 1:1 mixture of 45 mmol / L hexadecyltrimethylammonium bromide and 0.5 mol / L sodium persulfate was prepared as the electrochemical solution. 0.05 mol / L NaOH solution was added in small amounts several times until the pH of the solution stabilized at 8. Platinum electrodes were used for both the anode and cathode. The pulse current was set to 700 mA / g, the pulse period to 100 ms, the pulse signal duration to 30 ms-80 ms, and the total pulse time to 15 min. After the pulse electrochemical reaction, the electrochemical solution and sample were removed and washed three times by centrifugation, followed by six times by filtration. The sample was considered clean when no precipitate was formed in the filtrate after the final filtration, as determined by nitric acid and silver nitrate tests. 1 g of polysiloxane was added as an antifoaming agent before washing. Finally, the filter cake on the filter membrane was placed in a vacuum drying oven and dried at 50°C for 6 hours to obtain modified graphene oxide powder suitable for textile finishing agents.

[0041] Optical microscopy analysis was performed on the graphene oxide before and after modification in this embodiment, such as... Figure 4 and Figure 5 As shown, Figure 4 and Figure 5 The images show optical microscope images of graphene oxide before and after modification of cationic graphene oxide. The results show that the original sheet-like nanostructure of graphene oxide was not significantly affected after modification, indicating that the modified graphene oxide still retains the excellent properties of sheet-like nanoparticles.

[0042] Example 3

[0043] The experimental steps are as follows: 500 ml of pure water was mixed with graphene oxide powder at a concentration of 0.1 mg / ml, and dispersion was aided by a stirrer. The dispersed graphene oxide aqueous solution was filtered, and the filter cake on the filter membrane was collected for later use. 150 ml of a 1:1 mixture of 45 mmol / L hexadecyltrimethylammonium bromide and 0.5 mol / L sodium persulfate was prepared as an electrochemical solution, and 0.05 mol / L NaOH solution was added in small amounts several times.

[0044] The experimental procedure is as follows: 500 ml of pure water was mixed with graphene oxide powder at a concentration of 0.1 mg / ml, and dispersed using a stirrer. The dispersed graphene oxide aqueous solution was filtered, and the filter cake on the filter membrane was collected for later use. 150 ml of a 1:1 mixture of 45 mmol / L n-alkyl dimethyl benzyl ammonium chloride and 0.5 mol / L ammonium sulfate was prepared as the electrochemical solution. 0.05 mol / L NaOH solution was added in small amounts several times until the pH of the solution stabilized at 8. Titanium electrodes were used for both the anode and cathode. The pulse current was set to 650 mA / g, the pulse period to 100 ms, the pulse signal duration to 30 ms-80 ms, and the total pulse time to 15 min. After the pulse electrochemical reaction, the electrochemical solution and sample were removed and washed three times by centrifugation, followed by six times by filtration. The sample was considered clean if no precipitate was formed in the filtrate after the final filtration, as determined by silver nitrate testing. 1 g of polysiloxane was added as an antifoaming agent before washing. Finally, the filter cake on the filter membrane was placed in a vacuum drying oven and dried at 50°C for 6 hours to obtain modified graphene oxide powder suitable for textile finishing agents.

[0045] Infrared analysis was performed on the graphene oxide before and after modification in this embodiment. Figure 6 The Fourier transform infrared (FTIR) spectrum of the modified graphene oxide (labeled "2") after DC pulse electrochemical modification is shown in comparison with that of the unmodified graphene oxide (labeled "1"). Some peaks in the absorption characteristics of the modified graphene oxide show a significant shift. The characteristic peaks of carboxyl and epoxy groups are located at 1730 cm⁻¹. -1 (COOH) and 1247cm -1 (COC) disappeared. An alkyl chain appeared at 1281 cm⁻¹. -1 (CC) stretching peak and 2922 cm⁻¹ -1 2850cm -1 (CH) stretching peak, 1375 cm⁻¹ for amino groups. -1 (NH) curved peak and ammonium cation at 1465 cm⁻¹ -1 (CN) stretching peak. Therefore, the modified graphene oxide underwent an ammoniation reaction and can be stably dispersed in cationic textile finishing agents.

[0046] Comparative Example 1

[0047] The experimental steps are as follows: 500 ml of pure water was mixed with graphene oxide powder at a concentration of 0.1 mg / ml, and dispersed using a stirrer. The dispersed graphene oxide aqueous solution was filtered, and the filter cake on the filter membrane was collected for later use. 150 ml of a 1:1 mixture of 45 mmol / L n-alkyl dimethyl benzyl ammonium chloride and 0.5 mol / L ammonium sulfate was prepared as the electrochemical solution. 0.05 mol / L NaOH solution was added in small amounts several times until the pH of the solution stabilized at 8. Titanium electrodes were used for both the anode and cathode. A DC power supply was used for the electrochemical reaction. The current was set at 650 mA, and the electrochemical time was 15 min. After the electrochemical reaction, the electrochemical solution and sample were removed and washed three times by centrifugation, followed by six times by filtration. The sample was considered clean if no precipitate was formed in the filtrate after the final filtration, as determined by silver nitrate testing. 1 g of defoaming agent polysiloxane was added before washing. Finally, the filter cake on the filter membrane was placed in a vacuum drying oven at 50℃ for 6 h to obtain modified graphene oxide powder.

[0048] The graphene oxide powders before and after modification in this comparative example were dispersed in the same textile anti-dyeing paste auxiliary agent as in Example 1, and the results are as follows: Figure 7 As shown. Figure 7 The images show the dispersion effects of graphene oxide before and after modification in resist dyeing paste after 24 hours under DC electrochemical modification conditions. The left side represents the state before modification, and the right side represents the state after modification. The results indicate that the modified graphene oxide obtained by electrolysis under DC power supply conditions is not effective and cannot achieve good dispersion in cationic textile finishing agents. Therefore, DC pulse electrolysis is the key to the experiment.

[0049] This is because the grafting under ordinary DC electrolysis is not as strong or firm as that under pulse electrolysis, and the grafting effect is not firm, so the modified graphene oxide cannot be stably dispersed in textile finishing agents for a long time, resulting in poor modification effect.

[0050] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A method for preparing modified graphene oxide for textile finishing agents, characterized in that, A graphene oxide film is connected to a cathode electrode, and an alkaline electrochemical solution obtained by mixing a cationic modifier and a conductivity enhancer is used as the electrolyte. The modified graphene oxide is obtained after pulse electrochemical treatment and post-treatment. The conditions for the pulsed electrochemical treatment include: a pulsed current of 600mA-900mA / g applied per unit mass, a pulse period of 100ms, a pulse signal duration of 30ms-80ms, and a total pulse time of 10-15min.

2. The method for preparing modified graphene oxide for textile finishing agents according to claim 1, characterized in that, The method for preparing the graphene oxide film includes: filtering a graphene oxide dispersion of 1-1.5 mg / ml to obtain a graphene oxide filter cake, which is the graphene oxide film.

3. The method for preparing modified graphene oxide for textile finishing agents according to claim 2, characterized in that, The moisture content of the graphene oxide filter cake is 30%-70%.

4. The method for preparing modified graphene oxide for textile finishing agents according to claim 1, characterized in that, The cationic modifier is one or more of the following: dodecyl dimethyl benzyl ammonium bromide, dodecyl dimethyl phenoxyethyl ammonium bromide, dialkyl dimethyl ammonium chloride, didecyl ammonium chloride, n-alkyl dimethyl benzyl ammonium chloride, dodecyl trimethyl ammonium chloride, dodecyl dimethyl benzyl ammonium chloride, didodecyl dimethyl ammonium chloride, and hexadecyl trimethyl ammonium bromide.

5. The method for preparing modified graphene oxide for textile finishing agents according to claim 1, characterized in that, The conductivity enhancer is one or more of potassium nitrate, sodium nitrate, ammonium nitrate, ammonium persulfate, ammonium sulfate, potassium persulfate, potassium sulfate, sodium persulfate, and sodium sulfate.

6. The method for preparing modified graphene oxide for textile finishing agents according to claim 1, characterized in that, The electrochemical solution is formulated by mixing 45 mmol / L-55 mmol / L of cationic modifier and 0.5 mol / L-0.6 mol / L of conductivity enhancer in a 1:1 ratio.

7. The method for preparing modified graphene oxide for textile finishing agents according to claim 1, characterized in that, The pH value of the electrochemical solution is 8-9.

8. The method for preparing modified graphene oxide for textile finishing agents according to claim 1, characterized in that, The post-treatment includes cleaning and drying. During cleaning, 1g-3g of defoamer is added. The defoamer is one or more of polysiloxane, silicone emulsion, polyurethane, and polyacrylamide.

9. The method for preparing modified graphene oxide for textile finishing agents according to claim 8, characterized in that, The drying temperature is 50℃-60℃, and the time is 6h-8h.

10. A modified graphene oxide, characterized in that, It is prepared by the preparation method according to any one of claims 1-9.

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