阅读说明：本技术 一种缓释二氧化氯薄膜的制备方法 (Preparation method of slow-release chlorine dioxide film ) 是由 郝维军 臧子宜 于 2020-11-10 设计创作，主要内容包括：本发明公开了一种缓释二氧化氯薄膜的制备方法,涉及化工品制备技术领域,该方法包括：(1)制备内膜；(2)在内膜表面制备缓释控制层；(3)在缓释控制层表面制备二氧化氯释放层；(4)在二氧化氯释放层表面制备外膜；所述缓释控制层中包括碱,所述二氧化氯释放层中包括二氧化氯前体和酸性固体。本发明提供的缓释二氧化氯薄膜的制备方法,并非如传统方法一般,简单地将二氧化氯或其前体或其微胶囊分散在薄膜中的某一层的基体成膜材料中,而是将二氧化氯前体制备如多层结构的固体颗粒中,通过该固体颗粒与多层膜结构共同发挥作用,双重调节控制二氧化氯的缓释。(The invention discloses a preparation method of a slow-release chlorine dioxide film, which relates to the technical field of chemical preparation, and comprises the following steps: (1) preparing an inner membrane; (2) preparing a slow release control layer on the surface of the inner membrane; (3) preparing a chlorine dioxide release layer on the surface of the slow release control layer; (4) preparing an outer film on the surface of the chlorine dioxide release layer; the slow release control layer comprises alkali, and the chlorine dioxide release layer comprises a chlorine dioxide precursor and an acidic solid. The preparation method of the slow-release chlorine dioxide film provided by the invention is not that the traditional method is generally used, the chlorine dioxide or the precursor thereof or the microcapsule thereof is simply dispersed in the matrix film-forming material of a certain layer in the film, but the chlorine dioxide precursor is prepared into solid particles with a multilayer structure, and the solid particles and the multilayer film structure act together to double regulate and control the slow release of the chlorine dioxide.)

1. A preparation method of a slow-release chlorine dioxide film is characterized by comprising the following steps: the method comprises the following steps:

(1) preparing an inner membrane;

(2) preparing a slow release control layer on the surface of the inner membrane;

(3) preparing a chlorine dioxide release layer on the surface of the slow release control layer;

(4) preparing an outer film on the surface of the chlorine dioxide release layer;

the slow release control layer comprises alkali, and the chlorine dioxide release layer comprises a chlorine dioxide precursor and an acidic solid.

2. The method for preparing a sustained-release chlorine dioxide film according to claim 1, wherein: the preparation method of the inner membrane in the step (1) comprises the following steps: EVA resin and linear low-density polyethylene are melt blended and then processed into a film on casting film forming equipment; wherein the melt mass ratio of the EVA resin to the linear low-density polyethylene is (3-5) to (10-20).

3. The method for preparing a sustained-release chlorine dioxide film according to claim 1, wherein: the preparation method of the sustained-release control layer in the step (2) comprises the following steps: dispersing solid alkali into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and casting to form a film on the surface of an inner film.

4. The method for preparing a sustained-release chlorine dioxide film according to claim 3, wherein: in the step (2), the mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is (10-30) to (5-9); the solid alkali is added in an amount of 15-30 wt% of the linear low density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 2-5 wt% of the linear low density polyethylene; the solid alkali is one or more of sodium carbonate, potassium carbonate, sodium phosphate, sodium hydroxide and potassium hydroxide.

5. The method for preparing a sustained-release chlorine dioxide film according to claim 1, wherein: the preparation method of the chlorine dioxide release layer in the step (3) comprises the following steps:

1) soaking a spherical porous water-absorbing carrier material in alkali liquor, and drying to form a spherical object which is a solid core part for slowly releasing chlorine dioxide;

2) mixing a powdery porous water-absorbing carrier material with a chlorine dioxide precursor in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the mixture on the surface of the core part obtained in the step 1) by spraying, and drying to form an inner precursor layer;

3) mixing a powdery porous water-absorbing carrier material with a starch adhesive in a ball mill, adding deionized water, uniformly mixing, coating the surface of the inner precursor layer obtained in the step 2) by spraying, and drying to form an isolating layer;

4) mixing a powdery porous water-absorbing carrier material with a chlorine dioxide precursor in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the surface of the isolating layer obtained in the step 3) by spraying, and drying to form an outer precursor layer;

5) mixing a powdery porous water-absorbing carrier material with an acidic solid in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the mixture on the surface of the outer precursor layer obtained in the step 4) by spraying, and drying to form an acidification layer to obtain solid slow-release chlorine dioxide particles;

6) dispersing the solid slow-release chlorine dioxide particles obtained in the step 5) into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of the slow-release control layer to form a film.

6. The method for preparing a sustained-release chlorine dioxide film according to claim 5, wherein: in the step (3), the mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is (10-30) to (5-9); the adding amount of the solid slow-release chlorine dioxide particles is 40-66 wt% of the linear low-density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 2-5 wt% of the linear low density polyethylene.

7. The method for preparing a sustained-release chlorine dioxide film according to claim 6, wherein: the spherical porous water absorbing material in the step 1) is one or two of a molecular sieve and mesoporous silicon, and the particle size is 0.01-0.1 mm; the alkali liquor in the step 1) is one or more than two of sodium carbonate, potassium carbonate, sodium phosphate, sodium hydroxide and potassium hydroxide; the concentration of the alkali liquor is 0.5-1M.

8. The method for preparing a sustained-release chlorine dioxide film according to claim 6, wherein: step 2) -step 5) the powdery porous water absorption carrier material is one or more than two of molecular sieve, mesoporous silicon, activated alumina and gas-phase silicon dioxide, and the particle size is 0.003-0.008 mm; the chlorine dioxide precursor in the step 2) is one or more than two of sodium chlorite, potassium chlorite, calcium chlorite and magnesium chlorite; and step 2) the mass ratio of the powdery porous water absorption carrier material to the chlorine dioxide precursor and the deionized water is (2-9): (5-15): (3-20).

9. The method for preparing a sustained-release chlorine dioxide film according to claim 5, wherein: obtaining said core mass as m₁Inner precursor layer mass m₂Outer precursor layer mass m₃Mass of acidizing layer is m₄And the total mass of the obtained solid slow-release chlorine dioxide particles is M, the following components are obtained: m is₁＝μ₁(m₂+m₃)，m₄＝μ₂(m₂+m₃)，m₂+m₃＝μ₃M; where μ is a constant, μ₁0.01-0.2, mu₂0.005-0.1, mu₃Is 0.2-0.7.

10. The method for preparing a sustained-release chlorine dioxide film according to claim 5, wherein: the thickness of the inner film is set to be h₁The thickness of the slow release control layer is h₂The thickness of the chlorine dioxide release layer is h₃The thickness of the outer membrane is h₄Then, there are:

Technical Field

The invention relates to the technical field of chemical preparation, in particular to a preparation method of a slow-release chlorine dioxide film.

Background

Chlorine dioxide is an internationally recognized safe and nontoxic green disinfectant, can kill viruses, bacteria, protists, algae, fungi, various spores and thalli formed by the spores, is very little influenced by temperature, has high and stable sterilization efficiency, does not generate chlorination reaction with organic matters in the disinfection process, does not generate three-cause substances or other toxic substances, has no toxic or side effect on human bodies under normal use concentration, and is an effective component of a disinfection product which is widely applied at present.

The chlorine dioxide is prepared into a film structure, so that a plurality of functional materials such as disinfection sheets, sterilization packaging bags and the like can be generated.

Solid chlorine dioxide is generally used in a chlorine dioxide film structure rather than liquid, solid chlorine dioxide disinfectants are various in forms, and more breakthroughs are made in recent years, but reaction type solid chlorine dioxide is mainly adopted in the market, the solid chlorine dioxide is usually prepared into a monobasic or dibasic packaged solid dosage form by taking chlorate and chlorite as precursors and mixing the solid chlorine dioxide with acidic solids, water is added during use or water is absorbed through a carrier to react to generate chlorine dioxide gas, the gas is released to generate a disinfection effect, the action principle of the solid chlorine dioxide is not changed after the solid chlorine dioxide is prepared into a film, the disinfectant controls the release speed of the chlorine dioxide gas by adding the amount of the acidic solids, but the precursor and the acidic solids are in a mixed state from the beginning of reaction, the control is very difficult, the reaction is easily finished in a short time, The chlorine dioxide gas is released in a large amount, and then the disinfectant is in failure. To solve this problem, it is studied to add solid base into the formulation, which does achieve the overall sustained release, however, the existence of the solid base mixed with the precursor inevitably increases the overall initiation time, so that the disinfectant cannot take effect quickly, that is, the method also has a contradiction between the quick and sustained release effects. Further, there is another study on a method of microencapsulating chlorine dioxide and then coating the microencapsulated chlorine dioxide with an activator, a plasticizer, a film-forming agent, or the like, and this method has a problem that once chlorine dioxide is released, the release of chlorine dioxide is completed in a short time, as in the above-mentioned method.

Disclosure of Invention

In order to solve the problems of the chlorine dioxide film preparation technology, the invention provides a novel preparation method of a slow-release chlorine dioxide film, and the scheme is as follows:

a preparation method of a slow-release chlorine dioxide film comprises the following steps:

(1) preparing an inner membrane;

(2) preparing a slow release control layer on the surface of the inner membrane;

(3) preparing a chlorine dioxide release layer on the surface of the slow release control layer;

(4) preparing an outer film on the surface of the chlorine dioxide release layer.

The slow release control layer comprises alkali, and the chlorine dioxide release layer comprises a chlorine dioxide precursor and an acidic solid.

Preferably, the preparation method of the inner membrane in the step (1) comprises the following steps: EVA resin and linear low-density polyethylene are melt blended and then processed into a film on casting film forming equipment; wherein the melt mass ratio of the EVA resin to the linear low-density polyethylene is (3-5) to (10-20).

Preferably, the preparation method of the sustained-release control layer in the step (2) comprises the following steps: dispersing solid alkali into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and casting to form a film on the surface of an inner film.

Preferably, the mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is (10-30) to (5-9); the solid alkali is added in an amount of 15-30 wt% of the linear low density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 2-5 wt% of the linear low density polyethylene. The solid alkali is one or more of sodium carbonate, potassium carbonate, sodium phosphate, sodium hydroxide and potassium hydroxide.

Preferably, the preparation method of the chlorine dioxide release layer in the step (3) comprises the following steps:

1) soaking a spherical porous water-absorbing carrier material in alkali liquor, and drying to form a spherical object which is a solid core part for slowly releasing chlorine dioxide;

2) mixing a powdery porous water-absorbing carrier material with a chlorine dioxide precursor in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the mixture on the surface of the core part obtained in the step 1) by spraying, and drying to form an inner precursor layer;

3) mixing a powdery porous water-absorbing carrier material with a starch adhesive in a ball mill, adding deionized water, uniformly mixing, coating the surface of the inner precursor layer obtained in the step 2) by spraying, and drying to form an isolating layer;

4) mixing a powdery porous water-absorbing carrier material with a chlorine dioxide precursor in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the surface of the isolating layer obtained in the step 3) by spraying, and drying to form an outer precursor layer;

5) mixing a powdery porous water-absorbing carrier material with an acidic solid in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the mixture on the surface of the outer precursor layer obtained in the step 4) by spraying, and drying to form an acidification layer to obtain solid slow-release chlorine dioxide particles;

6) dispersing the solid slow-release chlorine dioxide particles obtained in the step 5) into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of the slow-release control layer to form a film.

Preferably, the mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is (10-30) to (5-9); the adding amount of the solid slow-release chlorine dioxide particles is 40-66 wt% of the linear low-density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 2-5 wt% of the linear low density polyethylene.

Preferably, the spherical porous water absorbing material in the step 1) is one or two of a molecular sieve and mesoporous silicon, and the particle size is 0.01-0.1 mm.

Preferably, the alkali liquor in step 1) is one or more than two of sodium carbonate, potassium carbonate, sodium phosphate, sodium hydroxide and potassium hydroxide. The concentration of the alkali liquor is 0.5-1M.

The drying involved in the invention is hot air drying at 30-60 ℃.

Preferably, the powdery porous water absorption carrier material in the steps 2) to 5) is one or more than two of molecular sieve, mesoporous silicon, activated alumina and fumed silica, and the particle size is 0.003-0.008 mm.

Preferably, the chlorine dioxide precursor in step 2) is one or more than two of sodium chlorite, potassium chlorite, calcium chlorite and magnesium chlorite.

Preferably, the mass ratio of the powdery porous water absorption carrier material in the step 2) to the chlorine dioxide precursor and the deionized water is (2-9): (5-15): (3-20).

Preferably, the starch adhesive in step 3) comprises a composite starch adhesive or a bonding agent and the like, wherein the main component is starch or modified starch, and the starch adhesive can be purchased from the market or prepared by the existing published method.

Preferably, the mass ratio of the porous water-absorbing carrier material, the starch adhesive and the deionized water in the step 3) is (2-9): (2-7): (5-30).

Preferably, the mass ratio of the powdery porous water absorption carrier material in the step 4) to the chlorine dioxide precursor and the deionized water is (2-9): (3-8): (3-20).

Preferably, the acidic solid in step 5) is one or more of sodium sulfate, sodium phosphate, potassium sulfate and potassium phosphate.

Preferably, the mass ratio of the powdery porous water absorption carrier material in the step 5) to the acidic solid and the deionized water is (2-9): (5-11): (3-20).

Preferably, the core mass is assumed to be m₁Inner precursor layer mass m₂Outer precursor layer mass m₃Mass of acidizing layer is m₄And the total mass of the obtained solid slow-release chlorine dioxide particles is M, the following components are obtained: m is₁＝μ₁(m₂+m₃)，m₄＝μ₂(m₂+m₃)，m₂+m₃＝μ₃M; where μ is a constant, μ₁0.01-0.2, mu₂0.005-0.1, mu₃Is 0.2-0.7.

Preferably, the core particle diameter is set to d₁The thickness of the inner precursor layer is L₂The thickness of the isolation layer is L_kThe thickness of the outer precursor layer is L₃The thickness of the acidified layer is L₄Then, there are:

preferably, the preparation method of the outer membrane in the step (4) comprises the following steps: taking a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of the chlorine dioxide release layer to form a film. More preferably, the mass ratio of the linear low density polyethylene to the solvent-based acrylic resin binder is (10-30): (1-3); the plasticizer is acetyl tributyl citrate, and the addition amount is 2-5 wt% of the linear low density polyethylene.

Preferably, the thickness of the inner film is set to h₁The thickness of the slow release control layer is h₂The thickness of the chlorine dioxide release layer is h₃The thickness of the outer membrane is h₄Then, there are:

after the slow-release chlorine dioxide film with the multilayer film structure is prepared according to the method, the slow-release chlorine dioxide film can be put into application by cutting and heat sealing according to the product requirements.

Has the advantages that:

the invention has the beneficial effects that:

the preparation method of the slow-release chlorine dioxide film provided by the invention is not that the traditional method is generally used, the chlorine dioxide or the precursor thereof or the microcapsule thereof is simply dispersed in the matrix film-forming material of a certain layer in the film, but the chlorine dioxide precursor is prepared into solid particles with a multilayer structure, and the solid particles and the multilayer film structure act together to double regulate and control the slow release of the chlorine dioxide.

According to the invention, slow release regulators such as manganese compounds are not required to be added, the first slow release effect is realized by improving the particle structure of the solid chlorine dioxide preparation, and the regulation of alkali on the release speed of chlorine dioxide is realized while the negative influence of alkali in the solid particles on the activation speed is avoided by stipulating the mass relation and the thickness relation of each layer of the solid particles.

In addition, because the film structure is generally used in a large environment with high maximum humidity, a sustained-release control layer is additionally arranged between the inner film and the chlorine dioxide release layer in the multilayer film structure, when the environment humidity is too high, the release rate of the chlorine dioxide is increased, the layer plays a role, the release rate of the chlorine dioxide is properly slowed down, and finally the double control of the release rate of the chlorine dioxide by the solid particles and the layered structure is realized, so that the stable and long-acting sustained-release effect is achieved. Finally, the invention also provides a thickness algorithm relation among all layers of the multilayer film structure, and the multilayer film structure prepared by adopting the proportional relation in the range has the most long-acting and stable release of the chlorine dioxide.

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.

The following examples and comparative examples are parallel runs, with the same processing steps and parameters, unless otherwise indicated.

Preparation example 1 preparation of solid sustained-release chlorine dioxide granules:

(1) soaking a spherical porous water-absorbing carrier material in alkali liquor, and drying to form a spherical object which is a solid core part for slowly releasing chlorine dioxide;

(2) mixing a powdery porous water-absorbing carrier material with a chlorine dioxide precursor in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the mixture on the surface of the core part obtained in the step (1) by spraying, and drying to form an inner precursor layer;

(3) mixing a powdery porous water-absorbing carrier material with a starch adhesive in a ball mill, adding deionized water, uniformly mixing, coating the surface of the inner precursor layer obtained in the step (2) by spraying, and drying to form an isolating layer;

(4) mixing a powdery porous water-absorbing carrier material with a chlorine dioxide precursor in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the surface of the isolating layer obtained in the step (3) by spraying, and drying to form an outer precursor layer;

(5) and (3) mixing the powdery porous water-absorbing carrier material with the acidic solid in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the mixture on the surface of the outer precursor layer obtained in the step (4) by spraying, and drying to form an acidification layer.

The spherical porous water absorbing material in the step (1) is a molecular sieve with the particle size of 0.01 mm.

The alkali liquor in the step (1) is sodium carbonate. The concentration of the alkali liquor is 1M.

And (3) the powdery porous water-absorbing carrier material in the steps (2) to (5) is a molecular sieve with the particle size of 0.005 mm.

The chlorine dioxide precursor in the step (2) is sodium chlorite.

The mass ratio of the powdery porous water absorption carrier material in the step (2) to the chlorine dioxide precursor and the deionized water is 4:10: 15.

The starch adhesive in the step (3) is a compound starch adhesive, the main component of which is starch or modified starch, and the starch adhesive is purchased from the market.

And (4) the mass ratio of the porous water-absorbing carrier material, the starch adhesive and the deionized water in the step (3) is 5:5: 17.

And (4) the mass ratio of the powdery porous water absorption carrier material to the chlorine dioxide precursor to the deionized water is 4:5: 15.

The acidic solid in the step (5) is potassium phosphate.

And (4) the mass ratio of the powdery porous water absorption carrier material to the acidic solid to the deionized water is 5:8: 18.

Let the core mass be m₁Inner precursor layer mass m₂Outer precursor layer mass m₃Mass of acidizing layer is m₄And the total mass of the obtained solid slow-release chlorine dioxide particles is M, the following components are obtained: m is₁＝μ₁(m₂+m₃)，m₄＝μ₂(m₂+m₃)，m₂+m₃＝μ₃M; wherein mu is a constant，μ₁Is 0.12, mu₂0.05, mu₃Is 0.4.

Let the core particle diameter be d₁The thickness of the inner precursor layer is L₂The thickness of the isolation layer is L_kThe thickness of the outer precursor layer is L₃The thickness of the acidified layer is L₄Then, there are:

through performance detection verification (specific results are shown in the specification of the performance detection), the membrane material prepared by the solid slow-release chlorine dioxide prepared by the embodiment has no induction period for releasing chlorine dioxide, the chlorine dioxide can be released stably in the first day of use, and the stable release is kept in the next 50 days.

Preparation example 2 preparation of solid sustained-release chlorine dioxide granules:

(1) soaking a spherical porous water-absorbing carrier material in alkali liquor, and drying to form a spherical object which is a solid core part for slowly releasing chlorine dioxide;

(2) mixing a powdery porous water-absorbing carrier material with a chlorine dioxide precursor in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the mixture on the surface of the core part obtained in the step (1) by spraying, and drying to form an inner precursor layer;

(3) mixing a powdery porous water-absorbing carrier material with a starch adhesive in a ball mill, adding deionized water, uniformly mixing, coating the surface of the inner precursor layer obtained in the step (2) by spraying, and drying to form an isolating layer;

(4) mixing a powdery porous water-absorbing carrier material with a chlorine dioxide precursor in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the surface of the isolating layer obtained in the step (3) by spraying, and drying to form an outer precursor layer;

(5) and (3) mixing the powdery porous water-absorbing carrier material with the acidic solid in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the mixture on the surface of the outer precursor layer obtained in the step (4) by spraying, and drying to form an acidification layer.

The spherical porous water absorbing material in the step (1) is a molecular sieve with the particle size of 0.01 mm.

The alkali liquor in the step (1) is sodium carbonate. The concentration of the alkali liquor is 1M.

And (3) the powdery porous water-absorbing carrier material in the steps (2) to (5) is a molecular sieve with the particle size of 0.005 mm.

The chlorine dioxide precursor in the step (2) is sodium chlorite.

The mass ratio of the powdery porous water absorption carrier material in the step (2) to the chlorine dioxide precursor and the deionized water is 4:10: 15.

The starch adhesive in the step (3) is a compound starch adhesive, the main component of which is starch or modified starch, and the starch adhesive is purchased from the market.

And (4) the mass ratio of the porous water-absorbing carrier material, the starch adhesive and the deionized water in the step (3) is 5:5: 17.

And (4) the mass ratio of the powdery porous water absorption carrier material to the chlorine dioxide precursor to the deionized water is 4:5: 15.

The acidic solid in the step (5) is potassium phosphate.

And (4) the mass ratio of the powdery porous water absorption carrier material to the acidic solid to the deionized water is 5:8: 18.

The particle size of the prepared solid particles is basically the same as that of preparation example 1, but the thicknesses of the layers are respectively as follows: the core, inner precursor layer, isolation layer, outer precursor layer, acidified layer are all equal in thickness.

Preparation example 3 preparation of solid sustained-release chlorine dioxide granules:

(1) soaking a spherical porous water-absorbing carrier material in alkali liquor, and drying to form a spherical object which is a solid core part for slowly releasing chlorine dioxide;

(2) mixing a powdery porous water-absorbing carrier material with a chlorine dioxide precursor in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the mixture on the surface of the core part obtained in the step (1) by spraying, and drying to form an inner precursor layer;

(3) mixing a powdery porous water-absorbing carrier material with a starch adhesive in a ball mill, adding deionized water, uniformly mixing, coating the surface of the inner precursor layer obtained in the step (2) by spraying, and drying to form an isolating layer;

(4) mixing a powdery porous water-absorbing carrier material with a chlorine dioxide precursor in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the surface of the isolating layer obtained in the step (3) by spraying, and drying to form an outer precursor layer;

(5) and (3) mixing the powdery porous water-absorbing carrier material with the acidic solid in a ball mill, adding deionized water into the obtained mixture, uniformly mixing, coating the mixture on the surface of the outer precursor layer obtained in the step (4) by spraying, and drying to form an acidification layer.

The spherical porous water absorbing material in the step (1) is a molecular sieve with the particle size of 0.01 mm.

The alkali liquor in the step (1) is sodium carbonate. The concentration of the alkali liquor is 1M.

And (3) the powdery porous water-absorbing carrier material in the steps (2) to (5) is a molecular sieve with the particle size of 0.005 mm.

The chlorine dioxide precursor in the step (2) is sodium chlorite.

The mass ratio of the powdery porous water absorption carrier material in the step (2) to the chlorine dioxide precursor and the deionized water is 4:10: 15.

The starch adhesive in the step (3) is a compound starch adhesive, the main component of which is starch or modified starch, and the starch adhesive is purchased from the market.

And (4) the mass ratio of the porous water-absorbing carrier material, the starch adhesive and the deionized water in the step (3) is 5:5: 17.

And (4) the mass ratio of the powdery porous water absorption carrier material to the chlorine dioxide precursor to the deionized water is 4:5: 15.

The acidic solid in the step (5) is potassium phosphate.

And (4) the mass ratio of the powdery porous water absorption carrier material to the acidic solid to the deionized water is 5:8: 18.

The average particle mass of the prepared solid particles was substantially the same as that of preparation example 1, except that the mass of the core part, the inner precursor layer, the separation layer, the outer precursor layer, and the acidified layer each accounted for 20% wt of the total mass.

Example 1 preparation of a slow release chlorine dioxide film:

(1) preparing an inner membrane;

(2) preparing a slow release control layer on the surface of the inner membrane;

(3) preparing a chlorine dioxide release layer on the surface of the slow release control layer;

(4) preparing an outer film on the surface of the chlorine dioxide release layer.

The slow release control layer comprises alkali, and the chlorine dioxide release layer comprises a chlorine dioxide precursor and an acidic solid.

The preparation method of the inner membrane in the step (1) comprises the following steps: EVA resin and linear low-density polyethylene are melt blended and then processed into a film on casting film forming equipment; wherein the melting mass ratio of the EVA resin to the linear low-density polyethylene is 3: 17.

The preparation method of the sustained-release control layer in the step (2) comprises the following steps: dispersing solid alkali into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and casting to form a film on the surface of an inner film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 10: 9; the solid base is added in an amount of 15% wt of the linear low density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 2 wt% of the linear low density polyethylene. The solid alkali is sodium hydroxide.

The preparation method of the chlorine dioxide release layer in the step (3) comprises the following steps: dispersing the solid slow-release chlorine dioxide particles obtained in the preparation example 1 into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of a slow-release control layer to form a film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 10: 9; the adding amount of the solid slow-release chlorine dioxide particles is 40 percent by weight of the linear low-density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 2 wt% of the linear low density polyethylene.

The preparation method of the outer membrane in the step (4) comprises the following steps: taking a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of the chlorine dioxide release layer to form a film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 10: 3; the plasticizer is acetyl tributyl citrate, and the addition amount is 2 wt% of the linear low density polyethylene.

The thickness of the inner film is set to be h₁The thickness of the slow release control layer is h₂The thickness of the chlorine dioxide release layer is h₃The thickness of the outer membrane is h₄Then, there are:

example 2 preparation of a slow release chlorine dioxide film:

(1) preparing an inner membrane;

(2) preparing a slow release control layer on the surface of the inner membrane;

(3) preparing a chlorine dioxide release layer on the surface of the slow release control layer;

(4) preparing an outer film on the surface of the chlorine dioxide release layer.

The slow release control layer comprises alkali, and the chlorine dioxide release layer comprises a chlorine dioxide precursor and an acidic solid.

The preparation method of the inner membrane in the step (1) comprises the following steps: EVA resin and linear low-density polyethylene are melt blended and then processed into a film on casting film forming equipment; wherein the melt mass ratio of the EVA resin to the linear low-density polyethylene is 4: 15.

The preparation method of the sustained-release control layer in the step (2) comprises the following steps: dispersing solid alkali into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and casting to form a film on the surface of an inner film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 20: 7; the solid base is added in an amount of 20 wt% of the linear low density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene. The solid alkali is sodium phosphate.

The preparation method of the chlorine dioxide release layer in the step (3) comprises the following steps: dispersing the solid slow-release chlorine dioxide particles obtained in the preparation example 1 into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of a slow-release control layer to form a film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 20: 7; the adding amount of the solid slow-release chlorine dioxide particles is 53 wt% of the linear low-density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene.

The preparation method of the outer membrane in the step (4) comprises the following steps: taking a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of the chlorine dioxide release layer to form a film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 23: 2; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene.

The thickness of the inner film is set to be h₁The thickness of the slow release control layer is h₂The thickness of the chlorine dioxide release layer is h₃The thickness of the outer membrane is h₄Then, there are:

through performance detection (see the section of 'performance detection' in the specification), the slow-release effect gap between the comparative example 1 and the embodiment shows that the slow-release effect of the chlorine dioxide can be further enhanced by adopting the algorithm relationship among the film thicknesses of all layers in the multilayer film structure specified by the invention, so that the release of the chlorine dioxide of the film is long-acting and stable.

Comparative example 1 preparation of a slow-release chlorine dioxide film:

(1) preparing an inner membrane;

(2) preparing a slow release control layer on the surface of the inner membrane;

(3) preparing a chlorine dioxide release layer on the surface of the slow release control layer;

(4) preparing an outer film on the surface of the chlorine dioxide release layer.

The slow release control layer comprises alkali, and the chlorine dioxide release layer comprises a chlorine dioxide precursor and an acidic solid.

The preparation method of the inner membrane in the step (1) comprises the following steps: EVA resin and linear low-density polyethylene are melt blended and then processed into a film on casting film forming equipment; wherein the melt mass ratio of the EVA resin to the linear low-density polyethylene is 4: 15.

The preparation method of the sustained-release control layer in the step (2) comprises the following steps: dispersing solid alkali into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and casting to form a film on the surface of an inner film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 20: 7; the solid base is added in an amount of 20 wt% of the linear low density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene. The solid alkali is sodium phosphate.

The preparation method of the chlorine dioxide release layer in the step (3) comprises the following steps: dispersing the solid slow-release chlorine dioxide particles obtained in the preparation example 1 into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of a slow-release control layer to form a film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 20: 7; the adding amount of the solid slow-release chlorine dioxide particles is 53 wt% of the linear low-density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene.

The preparation method of the outer membrane in the step (4) comprises the following steps: taking a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of the chlorine dioxide release layer to form a film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 23: 2; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene.

The thickness of the prepared film is the same as that of the film prepared in the example 2, but the thickness of each layer of the inner film, the slow release control layer, the chlorine dioxide release layer and the outer film is the same.

Comparative example 2 preparation of a sustained-release chlorine dioxide film:

(1) preparing an inner membrane;

(2) preparing a slow release control layer on the surface of the inner membrane;

(3) preparing a chlorine dioxide release layer on the surface of the slow release control layer;

(4) preparing an outer film on the surface of the chlorine dioxide release layer.

The slow release control layer comprises alkali, and the chlorine dioxide release layer comprises a chlorine dioxide precursor and an acidic solid.

The preparation method of the inner membrane in the step (1) comprises the following steps: EVA resin and linear low-density polyethylene are melt blended and then processed into a film on casting film forming equipment; wherein the melt mass ratio of the EVA resin to the linear low-density polyethylene is 4: 15.

The preparation method of the sustained-release control layer in the step (2) comprises the following steps: dispersing solid alkali into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and casting to form a film on the surface of an inner film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 20: 7; the solid base is added in an amount of 20 wt% of the linear low density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene. The solid alkali is sodium phosphate.

The preparation method of the chlorine dioxide release layer in the step (3) comprises the following steps: dispersing the solid slow-release chlorine dioxide particles obtained in the preparation example 2 into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of the slow-release control layer to form a film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 20: 7; the adding amount of the solid slow-release chlorine dioxide particles is 53 wt% of the linear low-density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene.

The preparation method of the outer membrane in the step (4) comprises the following steps: taking a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of the chlorine dioxide release layer to form a film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 23: 2; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene.

Thickness of inner filmDegree of h₁The thickness of the slow release control layer is h₂The thickness of the chlorine dioxide release layer is h₃The thickness of the outer membrane is h₄Then, there are:

compared with the embodiment 2, the interlaminar mass/thickness ratio algorithm in the preparation of the solid slow-release chlorine dioxide particles can be seen to have positive influence on the overall chlorine dioxide slow-release effect of the membrane structure.

Comparative example 3 preparation of a sustained-release chlorine dioxide film:

(1) preparing an inner membrane;

(2) preparing a slow release control layer on the surface of the inner membrane;

(3) preparing a chlorine dioxide release layer on the surface of the slow release control layer;

(4) preparing an outer film on the surface of the chlorine dioxide release layer.

The slow release control layer comprises alkali, and the chlorine dioxide release layer comprises a chlorine dioxide precursor and an acidic solid.

The preparation method of the inner membrane in the step (1) comprises the following steps: EVA resin and linear low-density polyethylene are melt blended and then processed into a film on casting film forming equipment; wherein the melt mass ratio of the EVA resin to the linear low-density polyethylene is 4: 15.

The preparation method of the sustained-release control layer in the step (2) comprises the following steps: dispersing solid alkali into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and casting to form a film on the surface of an inner film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 20: 7; the solid base is added in an amount of 20 wt% of the linear low density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene. The solid alkali is sodium phosphate.

The preparation method of the chlorine dioxide release layer in the step (3) comprises the following steps: dispersing the solid slow-release chlorine dioxide particles obtained in the preparation example 3 into a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of the slow-release control layer to form a film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 20: 7; the adding amount of the solid slow-release chlorine dioxide particles is 53 wt% of the linear low-density polyethylene; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene.

The preparation method of the outer membrane in the step (4) comprises the following steps: taking a mixed solution of linear low-density polyethylene and a solvent type acrylic resin adhesive, adding a plasticizer, uniformly mixing, and carrying out tape casting on the surface of the chlorine dioxide release layer to form a film. The mass ratio of the linear low-density polyethylene to the solvent type acrylic resin adhesive is 23: 2; the plasticizer is acetyl tributyl citrate, and the addition amount is 4 wt% of the linear low density polyethylene.

The thickness of the inner film is set to be h₁The thickness of the slow release control layer is h₂The thickness of the chlorine dioxide release layer is h₃The thickness of the outer membrane is h₄Then, there are:

and (3) performance detection:

1. storage stability: according to the scheme provided by the invention, the chlorine dioxide precursor and the acid are stored in the solid slow-release chlorine dioxide particles, the chlorine dioxide precursor and the acid are separated and are not in direct contact, and the initial moisture is not contained in the chlorine dioxide particles, so that the storage stability is higher than that of all similar preparations on the market, the stability problem is not generated through stability detection in various forms, and the loss rate is almost zero.

2. The chlorine dioxide films obtained in all the examples and the comparative examples are cut and packaged into the same size, and are respectively filled into composite breathable bags with the same size and then into porous aluminum film bags, and the chlorine dioxide relative release rates of the chlorine dioxide films in the same room temperature environment are tested and compared by adopting the method in the invention CN201910357987.5, and the results are as follows:

all the examples can detect the release of chlorine dioxide on the day of use, basically have no induction period, and the release rate of chlorine dioxide is stable in the next 60 days; comparative example 2 has no induction period, but the subsequent chlorine dioxide release is unstable and decays rapidly after reaching the release peak on day 17; comparative example 3 the induction period was 2 days, almost no chlorine dioxide was released on the first day, the release started on the second day, and the release started immediately after the start of the release, and decayed rapidly after 19 days after the peak period. Comparative example 1 had no induction period and the chlorine dioxide release rate was smooth over the next 47 days.

It can be seen from the comparative example data that, the chlorine dioxide film prepared by using the method provided by the invention to encapsulate the chlorine dioxide precursor and the acid with the solid particles and adding the release-controlling alkali layer into the particles has a shorter induction period than that prepared by other methods, and a long period of chlorine dioxide release, even if the mass/thickness algorithm relationship between the layers of the specific film provided by the invention is not used, the curve of rapid decay after rapid release is changed, but the horizontal axis span of the curve is larger, the slope is small, that is, the product of the invention has more durable and stable chlorine dioxide release. Comparing the comparative example 1 with the example, it is demonstrated that the thickness relationship of each layer of the film using the algorithm relationship provided by the present invention can further improve the slow release effect of chlorine dioxide under the premise that the chlorine dioxide precursor and the acid are encapsulated by the solid particles. The difference in performance between examples 1 and 2 and comparative examples 2 and 3 shows that the specific algorithm set during the preparation of granules encapsulating chlorine dioxide precursor and acid according to the present invention provides a specific interlayer mass/thickness ratio that further enhances the sustained release effect of chlorine dioxide.

While the preferred embodiments and examples of the present invention have been described in detail, the present invention is not limited to the embodiments and examples, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art.