阅读说明：本技术 一种二氧化氯缓释材料及其制备方法 (Chlorine dioxide slow-release material and preparation method thereof ) 是由 张娇霞 陈正扬 陈国安 王磊 刘建枰 于 2021-10-14 设计创作，主要内容包括：本发明公开了一种二氧化氯缓释材料及其制备方法,其由A/B试剂组成,其中A试剂为聚乙烯醇-马来酸酐吸水树脂作为基底,树脂内有二氧化氯稳定液,B试剂为弱酸性物质,使用时将A/B试剂混合；所述弱酸性物质为柠檬酸、酒石酸、苹果酸中的任意一种。本发明的有益效果为：本发明所制备获得的二氧化氯缓释材料,使用绿色无毒可回收的交联剂马来酸酐以及溶剂醋酸丁酯,制备工艺流程中使用的试剂均方便回收利用,不会造成环境污染；本发明制备的吸水树脂在弱酸性环境下也可稳定存放,且对其吸液性能影响不大,可用于吸收缓释液,加入适量活化液即可缓释产生二氧化氯。(The invention discloses a chlorine dioxide slow-release material and a preparation method thereof, wherein the chlorine dioxide slow-release material consists of an A/B reagent, the A reagent is polyvinyl alcohol-maleic anhydride water-absorbing resin as a substrate, chlorine dioxide stabilizing liquid is contained in the resin, the B reagent is a weakly acidic substance, and the A/B reagent is mixed when the chlorine dioxide slow-release material is used; the weakly acidic substance is any one of citric acid, tartaric acid and malic acid. The invention has the beneficial effects that: the chlorine dioxide slow-release material prepared by the invention uses the green, nontoxic and recyclable cross-linking agent maleic anhydride and the solvent butyl acetate, and reagents used in the preparation process flow are convenient to recycle and do not cause environmental pollution; the water-absorbent resin prepared by the invention can be stably stored in a weakly acidic environment, has little influence on the liquid absorption performance, can be used for absorbing slow-release liquid, and can slowly release and generate chlorine dioxide by adding a proper amount of activating liquid.)

1. A chlorine dioxide slow release material is characterized by comprising an A/B reagent, wherein the A reagent is polyvinyl alcohol-maleic anhydride water-absorbing resin as a substrate, chlorine dioxide stabilizing liquid is contained in the resin, the B reagent is a weakly acidic substance, and the A/B reagent is mixed when the chlorine dioxide slow release material is used.

2. A chlorine dioxide sustained-release material according to claim 1, wherein the weakly acidic substance is any one of citric acid, tartaric acid and malic acid.

3. The preparation method of the chlorine dioxide slow-release material is characterized by comprising the following steps:

(1) adding polyvinyl alcohol into a reaction kettle, adding a cross-linking agent and an organic solvent into the reaction kettle, stirring and dispersing the mixture uniformly at room temperature, heating the mixture to 85-95 ℃, and reacting the mixture at constant temperature for 2-3 hours;

(2) taking out the polyvinyl alcohol crosslinked polymer powder obtained in the step (1), washing the polyvinyl alcohol crosslinked polymer powder once by using an ethanol solution, placing the polyvinyl alcohol crosslinked polymer powder in a beaker containing an ethanol-sodium hydroxide solution, and performing saponification reaction for 10-60 min under the stirring condition, wherein the mass fraction of the ethanol-sodium hydroxide solution is 5%;

(3) washing the polyvinyl alcohol crosslinked polymer obtained in the step (2) by using an ethanol solution, and drying at 40-50 ℃;

(4) and (4) placing the water-absorbent resin obtained in the step (3) in a beaker, absorbing the chlorite solution, transferring the chlorite solution to a slow-release device, and adding an activating agent into the slow-release device.

4. The method for preparing a chlorine dioxide slow release material according to claim 3, wherein the mass ratio of the polyvinyl alcohol to the cross-linking agent is 0.3-0.45: 0.55-0.7.

5. The method as claimed in claim 3, wherein the degree of polymerization of the polyvinyl alcohol is 500-2400, and the degree of alcoholysis is 50-100%.

6. The method for preparing a chlorine dioxide slow release material according to claim 3, wherein the cross-linking agent is any one of maleic anhydride, phthalic anhydride type organic dianhydride, or glutaraldehyde or glyoxal type organic dialdehyde.

7. The method for preparing a chlorine dioxide slow release material according to claim 3, wherein the organic solvent is any one of butyl acetate, ethyl acetate, toluene or acetone.

Technical Field

The invention relates to a chlorine dioxide slow-release material and a preparation method thereof, in particular to a chlorine dioxide slow-release polyvinyl alcohol water-absorbent resin material and a preparation method thereof.

Background

Polyvinyl alcohol is a high molecular polymer with certain water solubility, has a simple chemical structural formula, only has hydroxyl as a side group on a main chain, and is generally white solid particles or powder at normal temperature. The simple chemical structure of the polyvinyl alcohol enables the polyvinyl alcohol to be subjected to crosslinking reaction with a plurality of crosslinking agents such as aldehyde crosslinking agents and anhydride crosslinking agents to form a water-insoluble crosslinking network structure at normal temperature. And the polyvinyl alcohol has almost no biotoxicity, and is widely applied to the fields of biomedicine, agricultural irrigation, food preservation and the like. With the continuous popularization of environmental protection concept in recent years, the pursuit of green environmental protection manufacturing process and products is just a great trend of material manufacturing and development, but due to the fact that polyvinyl alcohol has good hydrophilicity and is difficult to absorb a large amount of moisture, a cross-linking agent and a solvent which are commonly used in a cross-linking reaction generally have certain biological toxicity, the cross-linking agent and the solvent in the preparation process of the polyvinyl alcohol water-absorbent resin need to be optimized and improved.

Chlorine dioxide is a gas with strong oxidizing property, but in the safe range of concentration, it has excellent quality such as disinfection effect is showing, application scope is wide, safety and nonirritant, and a large amount of research data indicate, chlorine dioxide concentration is about 0.1ppm has showing sterilization effect, and chlorine dioxide concentration is no influence to the human body within 100ppm simultaneously. Therefore, chlorine dioxide is widely used as an industrial oxidant and bleaching agent, and also as a disinfectant for daily-use articles such as paper, food, and drinking water. However, chlorine dioxide is decomposed by light, and storage and transportation are difficult, and the like, and the application of chlorine dioxide is limited by the factors, and the preparation of the sustained-release chlorine dioxide preparation in a safe concentration range becomes a popular direction for practitioners to research along with the gradual improvement of safety requirements on living goods.

Chinese patent 202010267413.1 discloses a preparation method of immobilized chlorine dioxide sustained-release gel. The slow release gel is prepared by using NaY molecular sieve to support an activator citric acid and using sodium chlorite and sodium polyacrylate resin. Although the sodium polyacrylate resin is low in price, the ionic water-absorbing resin is easy to decompose in the acid environment of chlorine dioxide, so that the network structure is damaged, the ionic water-absorbing resin is inconvenient to serve as a long-acting slow-release agent, and the cost of the NaY molecular sieve is high.

In summary, the existing preparation process of the chlorine dioxide sustained-release resin cannot be completely green and nontoxic, and long-acting sustained release is still difficult to achieve, so that the preparation technology and the process operation flow of the sustained-release agent still need to be optimized.

Disclosure of Invention

The technical problem to be solved is as follows: aiming at the defects of the existing chlorine dioxide slow-release resin, the invention provides a green nontoxic chlorine dioxide slow-release resin material and a preparation method thereof.

The invention provides a chlorine dioxide slow-release material which is composed of an A/B reagent, wherein the A reagent is polyvinyl alcohol-maleic anhydride water-absorbing resin as a substrate, chlorine dioxide stabilizing liquid is contained in the resin, the B reagent is a weakly acidic substance, and the A/B reagent is mixed when the material is used.

Preferably, the weakly acidic substance is any one of citric acid, tartaric acid and malic acid.

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

(1) adding polyvinyl alcohol into a reaction kettle, adding a cross-linking agent and an organic solvent into the reaction kettle, stirring and dispersing the mixture uniformly at room temperature, heating the mixture to 85-95 ℃, and reacting the mixture at constant temperature for 2-3 hours;

(2) taking out the polyvinyl alcohol crosslinked polymer powder obtained in the step (1), washing the polyvinyl alcohol crosslinked polymer powder once by using an ethanol solution, placing the polyvinyl alcohol crosslinked polymer powder in a beaker containing an ethanol-sodium hydroxide solution, and performing saponification reaction for 10-60 min under the stirring condition, wherein the mass fraction of the ethanol-sodium hydroxide solution is 5%;

(3) washing the polyvinyl alcohol crosslinked polymer obtained in the step (2) by using an ethanol solution, and drying at 40-50 ℃;

(4) and (4) placing the water-absorbent resin obtained in the step (3) in a beaker, absorbing the chlorite solution, transferring the chlorite solution to a slow-release device, and adding an activating agent into the slow-release device.

Preferably, the mass ratio of the polyvinyl alcohol to the crosslinking agent is 0.3-0.45: 0.55-0.7

Preferably, the degree of polymerization of the polyvinyl alcohol is between 500-2400, and the degree of alcoholysis is between 50% and 100%.

Preferably, the crosslinking agent is any one of maleic anhydride, phthalic anhydride type organic dianhydride, or glutaraldehyde or glyoxal type organic dialdehyde.

Preferably, the organic solvent is any one of butyl acetate, ethyl acetate, toluene or acetone.

The invention has the beneficial effects that:

(1) the chlorine dioxide slow release material prepared by the invention uses the green, nontoxic and recyclable cross-linking agent maleic anhydride and the solvent butyl acetate, and reagents used in the preparation process flow are convenient to recycle and do not cause environmental pollution.

(2) The water-absorbent resin prepared by the invention can be stably stored in a weakly acidic environment, has little influence on the liquid absorption performance, can be used for absorbing slow-release liquid, and can slowly release and generate chlorine dioxide by adding a proper amount of activating liquid.

(3) The used reagent has low cost, the experimental operation is simple and convenient, and the industrial production is easy.

(4) After being fully mixed with the slow release liquid and the activating agent, the water-absorbent resin prepared by the invention is kept stand at a cool and shady place at room temperature for a slow release time period of 3-8 weeks, a slow release concentration curve is stable, the concentration of the produced chlorine dioxide gas is within a safe range and cannot influence a human body, and the slow release curve is shown in figure 2, so that the chlorine dioxide is still within an effective concentration range after being slowly released for 30 days.

(5) The nonionic water-absorbing resin does not receive H in the acidic environment of chlorine dioxide⁺The influence of (2) causes the structure to be damaged, and the water absorption is reduced, so that the chlorine dioxide slow-release agent has unique advantages in the aspect of chlorine dioxide slow-release agents.

Drawings

FIG. 1 is a drawing of a sustained release experimental apparatus in the example; the solid in the gas collecting bottle 1 is water-absorbent resin after absorbing the slow-release liquid, and the liquid potassium iodide solution is in the gas collecting bottle 2;

fig. 2 is a graph showing the sustained-release effect of the first to fourth embodiments.

Detailed Description

The present invention is further illustrated by the following experimental examples, but the scope of the present invention is not limited to the following experimental examples, but is defined by the description of the present invention and the claims.

Example one

The first step is as follows: preparation of Water-absorbent resin

Measuring 40ml of butyl acetate, adding the butyl acetate into a 100ml round-bottom flask, and mixing the butyl acetate with the water according to a mass ratio of 1: 1.5 respectively weighing 4g of polyvinyl alcohol and 6g of maleic anhydride solid, adding the polyvinyl alcohol into the round-bottom flask, uniformly stirring, adding the maleic anhydride into the round-bottom flask, stirring and dissolving, then heating to 85 ℃ in an oil bath, and stirring at constant temperature for reaction for 2.5 hours. 5g of sodium hydroxide and 35g of absolute ethyl alcohol are weighed, and the sodium hydroxide and the absolute ethyl alcohol are transferred to a beaker and stirred to dissolve for later use.

The polymer obtained from the isothermal reaction was transferred to a clean beaker and washed by adding 10ml of absolute ethanol. Transferring the washed solid into the beaker containing the sodium hydroxide-ethanol solution, saponifying for 30min under uniform stirring, washing again with 20ml absolute ethanol, placing the washed product in an evaporating dish, and drying in a constant-temperature oven at 60 deg.C for 6h

The second step is that: preparation of sustained-release materials

2g of the prepared polyvinyl alcohol water-absorbent resin is weighed and placed in a beaker, 8ml of a sodium chlorite solution with the mass fraction of 5% is measured and added into the beaker, and the polyvinyl alcohol water-absorbent resin is transferred into a gas collection bottle 1 after the water-absorbent resin absorbs the sodium chlorite solution. 4ml of tartaric acid solution with the concentration of 0.01mol/L is measured and added into the gas collection bottle 1, and the rubber stopper is tightly covered.

Example two

The first step is as follows: preparation of Water-absorbent resin

Measuring 40ml of toluene, adding the toluene into a 100ml round-bottom flask, and mixing the toluene according to a mass ratio of 1: 2 respectively weighing 4g of polyvinyl alcohol and 8g of maleic anhydride solid, adding the polyvinyl alcohol into the round-bottom flask, uniformly stirring, dissolving the maleic anhydride solid in acetone, adding the dissolved maleic anhydride solid into the round-bottom flask, stirring and dissolving, heating to 85 ℃ in an oil bath, and stirring at constant temperature for reaction for 2 hours. 5g of sodium hydroxide and 35g of absolute ethyl alcohol are weighed, and the sodium hydroxide and the absolute ethyl alcohol are transferred to a beaker and stirred to dissolve for later use.

The polymer obtained from the isothermal reaction was transferred to a clean beaker and washed by adding 10ml of absolute ethanol. Transferring the washed solid into the beaker containing the sodium hydroxide-ethanol solution, saponifying for 30min under uniform stirring, washing again with 20ml absolute ethanol, placing the washed product in an evaporating dish, and drying in a constant-temperature oven at 60 deg.C for 6h

The second step is that: preparation of sustained-release materials

2g of the prepared polyvinyl alcohol water-absorbent resin is weighed and placed in a beaker, 8ml of a sodium chlorite solution with the mass fraction of 5% is measured and added into the beaker, and the polyvinyl alcohol water-absorbent resin is transferred into a gas collection bottle 1 after the water-absorbent resin absorbs the sodium chlorite solution. 4ml of citric acid solution with the concentration of 0.01mol/L is measured and added into the gas collection bottle 1, and the rubber stopper is tightly covered.

EXAMPLE III

The first step is as follows: preparation of Water-absorbent resin

Measuring 40ml of ethanol, adding the ethanol into a 100ml round-bottom flask, and mixing the ethanol with the water according to a mass ratio of 1: 1.5 respectively weighing 4g of polyvinyl alcohol and 0.1g of glutaraldehyde solution, adding the polyvinyl alcohol into the round-bottom flask, uniformly stirring, adding the glutaraldehyde solution into the round-bottom flask, stirring for dissolving, heating to 70 ℃ in an oil bath, and stirring at constant temperature for reacting for 2.5 hours. 5g of sodium hydroxide and 35g of absolute ethyl alcohol are weighed, and the sodium hydroxide and the absolute ethyl alcohol are transferred to a beaker and stirred to dissolve for later use.

The polymer obtained from the isothermal reaction was transferred to a clean beaker and washed by adding 10ml of absolute ethanol. Transferring the washed solid into the beaker containing the sodium hydroxide-ethanol solution, saponifying for 30min under uniform stirring, washing again with 20ml absolute ethanol, placing the washed product in an evaporating dish, and drying in a constant-temperature oven at 60 deg.C for 6h

The second step is that: preparation of sustained-release materials

2g of the prepared polyvinyl alcohol water-absorbent resin is weighed and placed in a beaker, 8ml of a sodium chlorite solution with the mass fraction of 5% is measured and added into the beaker, and the polyvinyl alcohol water-absorbent resin is transferred into a gas collection bottle 1 after the water-absorbent resin absorbs the sodium chlorite solution. 4ml of lactic acid solution with the concentration of 0.01mol/L is measured and added into the gas collection bottle 1, and the rubber stopper is tightly covered.

Example four

The first step is as follows: preparation of Water-absorbent resin

Measuring 40ml of ethyl acetate, adding the ethyl acetate into a 100ml round-bottom flask, and mixing the ethyl acetate with the water according to a mass ratio of 1: 1.5 respectively weighing 4g of polyvinyl alcohol and 6g of maleic anhydride solid, adding the polyvinyl alcohol into the round-bottom flask, uniformly stirring, adding the maleic anhydride into the round-bottom flask, stirring and dissolving, then heating to 70 ℃ in an oil bath, and stirring at constant temperature for reacting for 2.5 hours. 5g of sodium hydroxide and 35g of absolute ethyl alcohol are weighed, and the sodium hydroxide and the absolute ethyl alcohol are transferred to a beaker and stirred to dissolve for later use.

The polymer obtained from the isothermal reaction was transferred to a clean beaker and washed by adding 10ml of absolute ethanol. Transferring the washed solid into the beaker containing the sodium hydroxide-ethanol solution, saponifying for 60min under uniform stirring, washing again with 20ml absolute ethanol, placing the washed product into an evaporating dish, and drying in a constant-temperature oven at 60 ℃ for 6h

The second step is that: preparation of sustained-release materials

2g of the prepared polyvinyl alcohol water-absorbent resin is weighed and placed in a beaker, 8ml of magnesium chlorite solution with the mass fraction of 5% is measured and added into the beaker, and the polyvinyl alcohol water-absorbent resin is transferred into a gas collection bottle 1 after the water-absorbent resin absorbs the magnesium chlorite solution. 4ml of malic acid solution with the concentration of 0.01mol/L is measured and added into the gas collection bottle 1, and the rubber stopper is tightly covered.