Gel-type chlorine dioxide slow-release agent and preparation method thereof

Abstract

The present application relates to a kind of gel type chlorine dioxide slow-release agent and its preparation method, to solve the defects of chlorine dioxide gas instability, short storage time of disinfectant product in prior art, the gel system of the present application includes: chlorite aqueous solution, gelling agent, graphene oxide, PH regulator and activator, the present application uses graphene oxide as chlorine dioxide gas regulator, utilizes the better adsorption performance of graphene oxide and its surface oxygen-containing functional group, synergistic effect with gelling agent, so that the reaction of chlorine dioxide gas is like a super micro chemical processing plant, establishes a "constantly evaporating, constantly replenishing" chlorine dioxide balance system, continuously releases chlorine dioxide gas, kills a variety of bacteria and viruses in air, purifies air, no secondary pollution, and low price.

Description

Technical Field

[0001] This invention relates to the field of gel disinfectant technology, specifically to a gel-type chlorine dioxide sustained-release agent and its preparation method. Background Technology

[0002] Chlorine dioxide (ClO2) is a globally recognized fourth-generation disinfectant. At room temperature, it is a yellowish-green gas, readily soluble in water, with a solubility five times that of chlorine at room temperature. It consists of one chlorine atom and two oxygen atoms, with 19 electrons in its outer electron shell. It is one of the few compounds in nature existing entirely as a monomeric free radical. Therefore, chlorine dioxide, as a gas dissolved in water, is a truly effective bactericide. Its bactericidal mechanism differs from acids and phenols, which only denature proteins, and also differs from the chlorination action of chlorine-containing disinfectants, which only inactivates microorganisms. Chlorine dioxide is a strong oxidizing agent, with an electrode potential E0 = 1.95V, exhibiting strong oxidizing properties. Chlorine dioxide contains 52.6% chlorine. 4+ Become Cl - During the process, five electrons are transferred, so its effective chlorine content is 52.6% * 5 = 263%. This means that chlorine dioxide's oxidative disinfection and sterilization ability is 2.63 times that of chlorine. Its sterilization mechanism involves the oxidative decomposition of amino acids in microbial proteins, leading to amino acid chain breakage and protein loss of function, thus killing the microorganisms. Simultaneously, it does not denature proteins during sterilization, has no effect on animal cells, and does not produce carcinogenic, teratogenic, or cancer-inducing substances. However, due to the instability of chlorine dioxide gas, its long-term storage and long-distance distribution have always been the most difficult problems to solve. On the other hand, with the continuous improvement of people's living standards and the strengthening of health awareness, the requirements for living environment and air quality are also increasing. However, pollution from home renovations and modern office facilities, as well as building materials such as plywood, adhesives, and paints, continuously release many toxic and harmful gases. The use of air conditioning systems increases indoor airborne bacteria. All of these pose serious threats to human health. Therefore, there is an urgent need in the market for a disinfection product that is non-toxic and harmless to the human body, does not affect normal work and study, and can continuously perform sterilization, disinfection, and deodorization to thoroughly improve the air quality of people's living spaces. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies, such as the instability of chlorine dioxide gas and the short shelf life of disinfection products. To this end, this invention provides a gel-type chlorine dioxide sustained-release agent and its preparation method. The gel system of this invention makes the reaction of chlorine dioxide gas resemble a micro-chemical processing plant, establishing a chlorine dioxide balance system of "continuous volatilization and continuous replenishment," which can continuously release chlorine dioxide gas, kill various bacteria and viruses in the air, purify the air, prevent secondary pollution, and is inexpensive.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] On one hand, the present invention provides a gel-type chlorine dioxide sustained-release agent, comprising: an aqueous solution of chlorite, a gelling agent, graphene oxide, a pH adjuster, and an activator.

[0006] Graphene oxide (GO) is a three-dimensional (3D) porous network with a well-developed interpenetrating structure, where graphene sheets are held together by π-π stacking and hydrogen bonding. Its unique two-dimensional planar structure and π-π conjugated system give it greater mechanical strength, higher specific surface area, and superior adsorption and thermal properties. Furthermore, the oxygen-containing functional groups on the surface of graphene oxide, such as carbonyl, hydroxyl, and carboxyl groups, can form good interfacial interactions through chemical bonds or hydrogen bonds, enabling it to form a stable colloidal dispersion system in water, thus improving the mechanical properties and stability of the hydrogel.

[0007] In this invention, the excellent adsorption properties of graphene oxide are utilized to improve the storage stability of chlorine dioxide in the gel system. The oxygen-containing functional groups (carbonyl, hydroxyl, carboxyl, etc.) in graphene oxide form hydrogen bonds with the hydroxyl, amino, or carboxyl groups in the gelling agent. The synergistic effect of these two groups effectively controls the stable release of chlorine dioxide at low concentrations. Mixing graphene oxide, the gelling agent, and water forms a three-dimensional gel structure. Furthermore, the oxygen-containing functional groups in graphene oxide give it good hydrophilicity, enabling it to form a stable colloidal dispersion system in water.

[0008] Furthermore, the mass content of the graphene oxide is 1-4%. If the graphene oxide content is too high, the adsorption effect of chlorine dioxide will be too strong, resulting in a lower slow-release concentration, which can only inhibit bacteria but not kill them; if the content is too low, the slow release will be too fast, resulting in a short storage time.

[0009] Furthermore, the gel-type chlorine dioxide sustained-release agent comprises the following components in weight percentage:

[0010]

[0011] The sum of the mass percentages of all components is equal to 100%, and the mass concentration of the chlorite aqueous solution is 1-4%.

[0012] Furthermore, the gel-type chlorine dioxide sustained-release agent also includes a chlorine dioxide aqueous solution stabilizer.

[0013] Furthermore, the gel-type chlorine dioxide sustained-release agent comprises the following components in weight percentage:

[0014]

[0015] The sum of the mass percentages of all components is equal to 100%, and the mass concentration of the chlorite aqueous solution is 1-4%.

[0016] More preferably, the gel-type chlorine dioxide sustained-release agent comprises the following components in weight percentage:

[0017]

[0018] The sum of the mass percentages of all components is equal to 100%, and the mass concentration of the chlorite aqueous solution is 1-4%.

[0019] Further, the chlorite is at least one of sodium chlorite, calcium chlorite, magnesium chlorite, potassium chlorite, and barium chlorite.

[0020] Further, the gelling agent is at least one of sodium alginate, sodium carboxymethyl cellulose, polyacrylic acid resin, polyacrylamide resin, and modified starch; preferably sodium alginate.

[0021] Furthermore, the pH adjuster is at least one of sodium citrate, sodium acetate, sodium tartrate, and sodium borate.

[0022] Furthermore, the chlorine dioxide aqueous solution stabilizer is at least one of sodium hydroxide, potassium hydroxide, and ammonia.

[0023] Furthermore, the activator is at least one selected from sodium dihydrogen phosphate, acetic acid, oxalic acid, phosphoric acid, citric acid, tartaric acid, arsenic acid, formic acid, and boric acid.

[0024] On the other hand, the present invention provides a method for preparing the above-mentioned gel-type chlorine dioxide sustained-release agent, comprising: adding a gelling agent, graphene oxide, an activator, a pH adjuster, and optionally a chlorine dioxide aqueous solution stabilizer to a chlorite aqueous solution, and stirring evenly to obtain the gel-type chlorine dioxide sustained-release agent.

[0025] The types of gelling agents, activators, pH adjusters, chlorites, and chlorine dioxide aqueous solution stabilizers are as described above.

[0026] Furthermore, the mass concentration of the chlorite aqueous solution is 1-4%, for example: 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, etc.

[0027] Furthermore, based on a total system mass of 100 parts, the amounts of each component are as follows: 65-85 parts of chlorite aqueous solution, 5-15 parts of gelling agent, 1-4 parts of graphene oxide, 6-11 parts of pH adjuster, and 2-5 parts of activator.

[0028] More preferably, before the reaction, a chlorine dioxide aqueous solution stabilizer is added to the chlorite aqueous solution. The chlorine dioxide aqueous solution stabilizer is at least one of sodium hydroxide, potassium hydroxide, and ammonia. Chlorite aqueous solutions are unstable and easily generate chlorine dioxide gas; adding an alkaline compound can stabilize the chlorine dioxide aqueous solution.

[0029] Furthermore, based on a total system mass of 100 parts, the amount of the chlorine dioxide aqueous solution stabilizer is 0.01 to 0.05 parts. Within this range, the chlorite aqueous solution is alkaline and can effectively stabilize chlorine dioxide.

[0030] The beneficial effects of this invention are as follows:

[0031] This invention utilizes the unique two-dimensional planar structure and π-π conjugated system of graphene oxide to give it excellent chlorine dioxide gas adsorption capacity. The oxygen-containing functional groups in graphene oxide are bonded to the gelling agent by hydrogen bonds to form a cross-linked structure. The cross-linked structure and adsorption can improve the storage performance of chlorine dioxide gas, reduce the volatilization of chlorine dioxide, enhance the stability of chlorine dioxide in the gel, prolong the release time of the gel, and effectively control the release concentration of chlorine dioxide in the gel.

[0032] Terminology Definition

[0033] Unless otherwise specified, the solvent used in the solutions of this invention is "deionized water".

[0034] Unless explicitly stated otherwise, all scopes referenced in this invention include end values.

[0035] The term "at least one" is used in this invention to describe the elements and components described herein. This is done merely for convenience and to provide a general meaning regarding the scope of the invention. This description should be understood to include one or at least one, and the singular includes the plural, unless clearly otherwise indicated.

[0036] All figures in this invention are approximate values, regardless of whether words such as "approximately" or "about" are used. The numerical values ​​may vary by 1%, 2%, 5%, 7%, 8%, 10%, etc. Whenever a number with a value of N is disclosed, any number having a value of N+ / -1%, N+ / -2%, N+ / -3%, N+ / -5%, N+ / -7%, N+ / -8%, or N+ / -10% will be explicitly disclosed, where "+ / -" indicates addition or subtraction, and the range between N-10% and N+10% is also disclosed.

[0037] Unless otherwise stated, the following definitions as used in this invention shall apply. For the purposes of this invention, chemical elements are consistent with the CAS version of the periodic table and the 75th edition of the *Handbook of Chemistry and Physics*, 1994. Furthermore, general principles of organic chemistry can be found in *Organic Chemistry*, Thomas Sorrell, University Science Books, Sausalito: 1999, and *March's Advanced Organic Chemistry* by Michael B. Smith and Jerry March, John Wiley & Sons, New York: 2007, the entire contents of which are incorporated herein by reference.

[0038] Unless otherwise defined, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although similar or equivalent methods and materials may be used in the implementation or testing of embodiments of this invention, suitable methods and materials are described below. All publications, patent applications, patents, and other references mentioned in this invention are incorporated herein by reference in their entirety, except where specific paragraphs are cited. In case of any conflict, this specification and its included definitions shall prevail. Furthermore, materials, methods, and examples are illustrative only and are not intended to be limiting. Detailed Implementation

[0039] The following description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0040] Example 1

[0041] (1) Weigh 70g of a 2% sodium chlorite aqueous solution and 0.04g of sodium hydroxide, mix and stir evenly to obtain an aqueous solution of agent A;

[0042] (2) Weigh 7.12g of sodium carboxymethyl cellulose, 2g of graphene oxide, 6.5g of sodium citrate and 2.9g of citric acid and mix them evenly to obtain solid agent B;

[0043] (3) Add solid agent B to aqueous solution of agent A and stir evenly to obtain gel-type chlorine dioxide sustained-release agent.

[0044] Examples 2-5, Comparative Examples 1-2

[0045] The preparation methods of Examples 2-5 and Comparative Examples 1-2 are the same as those of Example 1. The amount of raw materials used is as shown in Table 1. In Comparative Example 2, diatomaceous earth is used instead of graphene oxide.

[0046] Table 1

[0047]

[0048]

[0049] Performance testing

[0050] The storage stability and effective release time of the above-mentioned gel-type chlorine dioxide sustained-release agent were tested. The test results are shown in Table 2.

[0051] (1) Storage stability: Five samples were prepared for each formulation and sealed at room temperature. The samples were opened and tested for the slow release time of chlorine dioxide at 3, 6, 12, 24 and 30 months. The longest storage time with a slow release time of more than 1 month was the storage stability time.

[0052] (2) Relative release time: Take the prepared sample and directly test its chlorine dioxide release time.

[0053] Table 2

[0054] serial number Storage stability / month Duration of sustained release / day Example 1 24 138 Example 2 24 120 Example 3 24 160 Example 4 24 150 Example 5 24 145 Comparative Example 1 <12 20 Comparative Example 2 <12 30

[0055] As shown in Table 2, the storage stabilizer and sustained-release time of the gel product in the embodiments of the present invention are significantly better than those in the comparative example. This is because applying graphene oxide to the traditional gel system has the function of adsorbing chlorine dioxide and controlling the stable release of chlorine dioxide.

[0056] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A gel-type sustained-release chlorine dioxide agent, characterized in that, include: The mixture comprises an aqueous solution of chlorite, a gelling agent, graphene oxide, a pH adjuster, and an activator; the gelling agent is at least one of sodium alginate, sodium carboxymethyl cellulose, polyacrylic acid resin, polyacrylamide resin, and modified starch; the graphene oxide has a mass content of 1-4%.

2. The gel-type chlorine dioxide sustained-release agent according to claim 1, characterized in that, The gel-type chlorine dioxide sustained-release agent comprises the following components in weight percentage: The sum of the mass percentages of all components is equal to 100%, and the mass concentration of the chlorite aqueous solution is 1-4%.

3. The gel-type chlorine dioxide sustained-release agent according to claim 1, characterized in that, The gel-type chlorine dioxide sustained-release agent also includes a chlorine dioxide aqueous solution stabilizer.

4. The gel-type chlorine dioxide sustained-release agent according to claim 3, characterized in that, The gel-type chlorine dioxide sustained-release agent comprises the following components in weight percentage: The sum of the mass percentages of all components is equal to 100%, and the mass concentration of the chlorite aqueous solution is 1-4%.

5. The gel-type chlorine dioxide sustained-release agent according to any one of claims 1 to 4, characterized in that, The chlorite is at least one of sodium chlorite, calcium chlorite, magnesium chlorite, potassium chlorite, and barium chlorite.

6. The gel-type chlorine dioxide sustained-release agent according to any one of claims 1 to 4, characterized in that, The pH adjuster is at least one of sodium citrate, sodium acetate, sodium tartrate, and sodium borate.

7. The gel-type chlorine dioxide sustained-release agent according to claim 3 or 4, characterized in that, The chlorine dioxide aqueous solution stabilizer is at least one of sodium hydroxide, potassium hydroxide, and ammonia.

8. The gel-type chlorine dioxide sustained-release agent according to any one of claims 1 to 4, characterized in that, The activator is at least one of sodium dihydrogen phosphate, acetic acid, oxalic acid, phosphoric acid, citric acid, tartaric acid, arsenic acid, formic acid, and boric acid.

9. A method for preparing the gel-type chlorine dioxide sustained-release agent according to any one of claims 1 to 8, characterized in that, include: Add the gelling agent, graphene oxide, activator, pH adjuster, and optionally chlorine dioxide aqueous solution stabilizer to the chlorite aqueous solution and stir until homogeneous to obtain the gel-type chlorine dioxide sustained-release agent.

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