CN110200013B

CN110200013B - Antibacterial mildew preventive, and preparation method and application thereof

Info

Publication number: CN110200013B
Application number: CN201910537967.6A
Authority: CN
Inventors: 胡剑; 谢友能; 齐维靖; 张萌; 石思思
Original assignee: Jiangxi Ganda Material Technology Research Co ltd
Current assignee: Jiangxi Ganda Material Technology Research Co ltd
Priority date: 2019-06-20
Filing date: 2019-06-20
Publication date: 2020-04-14
Anticipated expiration: 2039-06-20
Also published as: CN110200013A

Abstract

The invention relates to an antibacterial mildew preventive, and particularly provides an antibacterial mildew preventive, and a preparation method and application thereof. The antibacterial mildew preventive is a copper oxide/zinc oxide composite nano particle with the copper doping amount of 0.5-10%, and the particle size is 20-300 nm. The copper-doped zinc oxide nano-particles have excellent antibacterial and mildewproof performances, when the addition amount is more than 1 percent of the weight of the bulk material, the antibacterial rate reaches more than 99 percent (first grade), and the mildewproof grade reaches 0 grade. The antibacterial mildew inhibitor has the advantages of simple preparation process, good product dispersion, lasting antibacterial performance, high efficiency, broad spectrum and convenient use, does not influence the properties of the body material after being added, and is suitable for industrial mass production and popularization.

Description

Antibacterial mildew preventive, and preparation method and application thereof

Technical Field

The invention relates to an antibacterial mildew preventive, in particular to a copper-doped zinc oxide antibacterial mildew preventive and a preparation method and application thereof.

Background

According to 2016 global death statistics published by the World Health Organization (WHO), it is known that death caused by infection of bacteria, viruses and the like is still a big factor of human death in the world, and particularly in low-income countries, the number of deaths caused by poor health conditions is more than half or even more of the total number of deaths. With the push of the 'big health' environment, people pay more and more attention to their health problems, the antibacterial awareness is generally improved, and the demand of antibacterial products is increasing. On the one hand, various bacterial resistances have emerged due to the abuse of antibiotics. On the other hand, the growth of the mold also causes inconvenience to people's daily life, and especially the mold of important documents, coins and the like causes serious property loss and the like. The emergence of inorganic antibacterial agents can solve the problem of bacterial resistance well. At present, the common inorganic antibacterial agents comprise nano silver and silver ion antibacterial agents, nano copper, nano zinc oxide and the like. However, the price of the nano silver is high, the nano copper is easy to oxidize and agglomerate, and the nano zinc oxide has relatively great advantages. However, the mildew-proof effect of nano silver and nano zinc oxide in the traditional inorganic antibacterial agent is not ideal.

Disclosure of Invention

In order to improve the antibacterial effect, particularly the mildew-proof effect, the invention provides an antibacterial mildew-proof agent which has the functions of high efficiency, broad spectrum and lasting antibiosis and mildew prevention.

The research of the invention finds that after a certain amount of copper oxide is doped into the zinc oxide nano particles, the antibacterial effect can be obviously improved, and the mildew-proof effect can be also unexpectedly improved, so that the invention is provided.

Specifically, the invention provides an antibacterial mildew inhibitor which is a copper oxide/zinc oxide composite nanoparticle; wherein, the copper doping amount is 0.5 percent to 10 percent, and the particle size is 20nm to 300 nm.

The copper-doped amount refers to the weight percentage of copper element in the antibacterial mildew preventive.

Further, the copper doping amount in the antibacterial and mildewproof agent is 2-6%, and particularly 4%.

In some embodiments of the present invention, the amount of copper doped in the antibacterial and antifungal agent is 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10%, respectively.

The research of the invention finds that the antibacterial and mildewproof effect is reduced when the copper doping amount in the antibacterial and mildewproof agent is too high or too low, such as more than 10 percent or less than 0.5 percent. And when the copper doping amount is 0.5-10%, especially 2-6%, especially 4%, excellent antibacterial and mildewproof performance can be obtained, and the antibacterial spectrum is expanded.

Preferably, the particle size of the antibacterial and antifungal agent is 50-100 nm.

Further research shows that the particle size of the antibacterial and mildewproof agent has a remarkable influence on the antibacterial and mildewproof performance, and the antibacterial and mildewproof effect is reduced when the particle size is too large or too small, such as the particle size is larger than 300nm or less than 20 nm. And when the particle size is 20-300nm, especially 50-100nm, excellent antibacterial and mildewproof performance can be obtained, and the antibacterial spectrum is expanded. In addition, although the antibacterial and antifungal agent has a good antibacterial property when the particles are small, the particles are easily agglomerated, and the excessively fine particles are not easily dispersed when used (for example, when added to a paint), resulting in uneven mixing and failing to achieve a good antibacterial and antifungal effect.

The invention also provides a preparation method of the antibacterial mildew preventive, which comprises the following steps:

taking copper salt and zinc salt according to the proportion, and dissolving the copper salt and the zinc salt in deionized water to prepare a solution;

adding a proper amount of sodium hydroxide into the solution, and uniformly stirring;

adding a proper amount of lauryl sodium sulfate ethanol solution heated to 50-120 ℃ for full reaction;

and (3) cleaning, drying and grinding the reaction product.

Further, the copper salt is selected from one or more of copper sulfate, copper chloride and the like.

Further, the zinc salt is selected from one or more of zinc nitrate, zinc acetate, zinc sulfate, zinc chloride and the like.

Furthermore, the dosage of the copper salt and the zinc salt is preferably 0.5 to 10 percent of copper doped in the prepared antibacterial and antifungal agent.

Further, sodium hydroxide is preferably added in the form of a solution.

Preferably, the sodium hydroxide is added in an amount of 1 to 5 times, more preferably 2 to 3 times, the total molar amount of the copper salt and the zinc salt. The method has the advantages that the method can ensure the complete conversion of the copper salt and the zinc salt and control the crystallization speed, thereby regulating and controlling the size of the generated copper oxide/zinc oxide composite nano-particles.

In the present invention, the ethanol solution of sodium dodecyl sulfate can be prepared by a conventional method in the art, for example, ethanol with a concentration of 60% to 80% is used as a solvent, and 80% ethanol is preferably used as a solvent. The concentration of sodium lauryl sulfate in the sodium lauryl sulfate ethanol solution is typically 0.01 to 0.05g/ml, for example 0.02 g/ml.

The research of the invention finds that the lauryl sodium sulfate ethanol solution (the solvent is preferably 80 percent ethanol) is heated to 50-120 ℃ in advance (preferably 80 ℃) and then added into the copper salt and zinc salt solution, and the invention has the advantages that the temperature can reach the optimal reaction temperature while the copper zinc salt solution is added, thereby evenly precipitating and reducing the size distribution of the obtained nano powder.

Preferably, the weight ratio of the sodium lauryl sulfate added to the sum of the weight of the copper salt and the zinc salt in the reaction system is 0.1 to 5:1, more preferably 1 to 3: 1. Under the condition, sodium dodecyl sulfate is used as a dispersing agent and is coated on the periphery of copper ions and zinc ions, so that the crystallization speed of the copper-zinc composite particles is reduced, and the particle size is reduced; meanwhile, the large anionic groups reduce the growth and agglomeration of generated nano particles, thereby improving the dispersibility of the nano particles.

After the reaction is finished, collecting the reaction product by a centrifugation method, wherein the reaction product can be centrifuged at 3000-10000r/min for 15-60 min; then washed with water, usually 2-5 times. Drying at 60-120 deg.C for 6-24 hr.

Specifically, the preparation method of the antibacterial and antifungal agent comprises the following steps:

s1, dissolving a proper amount of copper salt and zinc salt in deionized water to obtain a solution A;

s2, weighing a certain amount of sodium hydroxide according to the total amount of copper salts and zinc salts in the solution A, and dissolving the sodium hydroxide in deionized water to obtain a solution B;

s3, mixing the solution A obtained in the S1 with the solution B in the S2 to obtain a solution C;

s4, weighing a certain amount of sodium dodecyl sulfate, dissolving the sodium dodecyl sulfate in ethanol with the concentration of 60-80% to obtain a solution D, and heating to 50-120 ℃;

s5, adding the solution C obtained in the step S3 into the solution D obtained in the step S4, reacting for 1-6h, centrifuging for 15-60min at the speed of 3000-10000r/min, cleaning the obtained precipitate for 2-5 times, drying for 6-24h at the temperature of 60-120 ℃, and grinding to obtain the copper oxide/zinc oxide composite nano-particles, namely the antibacterial mildew preventive.

The invention also comprises the application of the antibacterial mildew preventive in the antibiosis and mildew prevention of materials.

For example, the antibacterial and antifungal agent can be added into an electrostatic spray coating (containing epoxy resin powder/metal powder, titanium dioxide powder, lithopone, an auxiliary agent and a pigment), mixed thoroughly, sieved, sprayed onto the surface of a material by an electrostatic spraying method, cured at 80-200 ℃ for 15-50 minutes, and taken out. Or the antibacterial mildew preventive is added into liquid such as glaze, paint and the like, and is uniformly dispersed in a stirring or ultrasonic oscillation mode for use.

The copper oxide/zinc oxide composite nano-particles prepared by the method have excellent antibacterial and mildewproof performances, can be used for antibacterial and mildewproof of various materials such as wood, plastics, printed matters, powder, fluid and the like, and can endow the body material with primary antibacterial capability and mildewproof grade above II level; and after the durability test, the same antibacterial and mildewproof effects before the durability can be achieved. When the addition amount of the antibacterial mildew preventive is more than 1% of the weight of the main body material, the antibacterial rate reaches more than 99% (first grade), and the mildew-proof grade reaches 0 grade. The antibacterial mildew inhibitor has the advantages of simple preparation process, good product dispersion, lasting antibacterial performance, high efficiency, broad spectrum and convenient use, does not influence the properties of the body material after being added, and is suitable for industrial mass production and popularization.

Drawings

FIG. 1 shows the results of the antibacterial property test of the copper oxide/zinc oxide composite nanoparticles of example 1.

FIG. 2 shows the results of the mildew resistance test of the copper oxide/zinc oxide composite nanoparticles of example 1.

Fig. 3 is SEM images of copper oxide/zinc oxide composite nanoparticles with different copper doping amounts.

Fig. 4 is an XRD pattern of copper oxide/zinc oxide composite nanoparticles with different copper doping amounts.

FIG. 5 is an XPS plot of copper oxide/zinc oxide composite nanoparticles of example 4.

Detailed Description

The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention. The examples do not show the specific techniques or conditions, according to the technical or conditions described in the literature in the field, or according to the product specifications. The reagents or instruments used are conventional products available from regular distributors, not indicated by the manufacturer.

Example 1

Weighing 0.25g of copper sulfate pentahydrate and 7.5g of zinc nitrate hexahydrate, and dissolving in 20ml of deionized water to obtain a solution A;

weighing 40g of sodium hydroxide, and dissolving in 20ml of deionized water to obtain a solution B;

mixing the solution A and the solution B to obtain a solution C;

10g of sodium dodecyl sulfate is weighed and dissolved in 500ml of 80% ethanol to obtain a solution D, the solution D is heated to 80 ℃, then the solution C is poured into the solution D, and the reaction is continued for 6 hours.

And after the solution is cooled, centrifuging the final solution in a centrifuge at the rotating speed of 8000r/min for 30min, pouring out the supernatant, taking the precipitate, washing the precipitate for 5 times in a reciprocating manner by using water until the precipitate is cleaned, then drying the cleaned precipitate in a drying box at the temperature of 120 ℃ for 12h, and grinding to obtain the copper oxide/zinc oxide composite nano-particles. Wherein the particle size is 50-100nm, and the copper doping amount is 4%.

The copper oxide/zinc oxide composite nanoparticles prepared in this example were tested for their antibacterial and antifungal properties by the institute of physical and chemical technology, national academy of sciences, and the results are shown in fig. 1 (test for antibacterial properties of electrostatic spray samples) and fig. 2 (test for antifungal properties of electrostatic spray samples). The result shows that the antibacterial and mildewproof performance is excellent.

Example 2

The only difference from example 1 is: the amount of copper sulfate pentahydrate was replaced with 0.125 g.

The size of the copper oxide/zinc oxide composite nano-particles prepared by the embodiment is 50-100nm, and the copper doping amount is 2%.

Example 3

The only difference from example 1 is: the amount of copper sulfate pentahydrate was replaced with 0.375 g.

The size of the copper oxide/zinc oxide composite nano-particles prepared by the embodiment is 50-100nm, and the copper doping amount is 6%.

Example 4

The only difference from example 1 is: the amount of copper sulfate pentahydrate was replaced with 0.625 g.

The copper oxide/zinc oxide composite nano-particles prepared by the embodiment have the size of 50-100nm and the copper doping amount of 10 percent

Example 5

The only difference from example 1 is: the dosage of the copper sulfate pentahydrate is replaced by 0.031 g.

The copper oxide/zinc oxide composite nano-particles prepared by the comparative example have the size of 50-100nm and the copper doping amount of 0.5 percent

Comparative example 1

The only difference from example 1 is: namely, only 7.75g of zinc nitrate hexahydrate and 20ml of deionized water are used for preparing solution A; the rest of the procedure was the same as in example 1.

The zinc oxide nano-particles prepared by the comparative example have the size of 50-100nm and the copper doping amount of 0 percent.

Comparative example 2

The only difference from example 1 is: solution A was prepared using only 7.75g copper sulfate pentahydrate and 20ml deionized water; the rest of the procedure was the same as in example 1.

The copper oxide nanoparticles prepared by the comparative example have the size of 50-100nm and contain no zinc.

Experimental example 1

Fig. 3 is SEM images of copper oxide/zinc oxide composite nanoparticles with different copper doping amounts, in which fig. 3A is a morphology of zinc oxide nanoparticles (copper doping amount is 0%) prepared in comparative example 1, fig. 3B is a morphology of copper oxide/zinc oxide composite nanoparticles (copper doping amount is 4%) prepared in example 1, fig. 3C is a morphology of copper oxide/zinc oxide composite nanoparticles (copper doping amount is 6%) prepared in example 3, and fig. 3D is a morphology of copper oxide/zinc oxide composite nanoparticles (copper doping amount is 10%) prepared in example 4.

Fig. 3 shows that the ZnO without copper doping prepared by the method of comparative example 1 is a sea urchin-shaped particle self-assembled by a steeple-top hexagonal prism with a diameter of about 50nm and a length of about 5 μm, and the morphology of the composite nanoparticle changes with the change of the copper doping amount, the composite particle corresponding to example 1 is a flower-shaped particle self-assembled by nanosheets, and the surface of the nanosheet has about tens of nanometers of fine flaky nanoparticles, so that the specific surface area of the composite particle can be further increased, and the nanosheets gradually become bamboo leaves and finally become needle-shaped with the continuous increase of the copper doping amount.

FIG. 4 is XRD patterns of the copper oxide/zinc oxide composite nanoparticles of examples 1 and 4 and the zinc oxide nanoparticles of comparative example 1, wherein "4% Cu-ZnO" and "10% Cu-ZnO" are the composite nanoparticles of examples 1 and 4, respectively; "ZnO" is the zinc oxide nanoparticles of comparative example 1.

As can be seen in FIG. 4, the background of all the peaks is low, indicating that the ZnO prepared by the method has good crystallinity, while the CuO peaks at 32.5 degrees, 35.5 degrees and 38.7 degrees become more obvious with the increase of the copper doping amount, but no elemental Cu and Cu are detected₂The peak of O, indicating that the copper incorporated is predominantly in the form of CuO.

Fig. 5 is XPS chart of the copper oxide/zinc oxide composite nanoparticle of example 4, wherein fig. 5A is XPS full spectrum and fig. 5B is Cu2p narrow spectrum.

As can be seen in FIG. 5, the copper in the composite particle has a small amount of elemental Cu or Cu in addition to CuO₂O, i.e., the valence of the copper doped is between 0 and 2, but since Cu/Cu₂The amount of O is too small to be below the detection limit of XRD, so that the corresponding peaks do not appear in FIG. 4.

Experimental example 2 antibacterial experiment

The antibacterial properties of the zinc oxide nanoparticles prepared in examples 1 to 5 and comparative examples 1 to 2 were respectively verified.

The experimental method comprises the following steps: refer to GB/T21866-;

detection bacteria: escherichia coli (Escherichia coli) AS 1.90;

staphylococcus aureus (Staphylococcus aureus) AS 1.89;

the results of the measurements are shown in Table 1 below.

TABLE 1

The results in table 1 show that the antibacterial performance of the copper oxide/zinc oxide composite nanoparticles prepared by the invention is significantly better than that of the zinc oxide composite nanoparticles (comparative example 1) and the copper oxide nanoparticles (comparative example 2), the antibacterial performance of the composite nanoparticles with moderate copper doping amount is the best, and the antibacterial effect is reduced when the copper doping amount is too high or too low.

Experimental example 3 mildew-proofing experiment

The mildewproof property of the zinc oxide nanoparticles prepared in examples 1 to 5 and comparative examples 1 to 2 was verified.

The experimental method comprises the following steps: reference is made to GB/T1741-2007 determination of the resistance to mildew of paint films;

detection bacteria: see table 2 below.

The results of the measurements are shown in Table 2 below.

TABLE 2

The results in table 2 show that the mildew resistance of the copper oxide/zinc oxide composite nanoparticles prepared by the invention is obviously superior to that of the zinc oxide composite nanoparticles (comparative example 1) and the copper oxide nanoparticles (comparative example 2), the mildew resistance of the composite nanoparticles with moderate copper doping amount is the best, and the mildew resistance is reduced by over-high or over-low copper doping amount.

Although the invention has been described in detail hereinabove with respect to a general description and specific embodiments thereof, it will be apparent to those skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims

1. An antibacterial mildew preventive is a copper oxide/zinc oxide composite nano-particle with the copper doping amount of 0.5-10%, and the particle size is 20-300 nm;

the preparation method of the antibacterial mildew preventive comprises the following steps:

s2, weighing a certain amount of sodium hydroxide according to the total amount of copper salts and zinc salts in the solution A, and dissolving the sodium hydroxide in deionized water to obtain a solution B; the adding amount of the sodium hydroxide is 2-3 times of the total molar amount of the copper salt and the zinc salt;

s4, weighing a certain amount of sodium dodecyl sulfate, dissolving the sodium dodecyl sulfate in ethanol with the concentration of 60-80% to obtain a solution D, and heating to 50-80 ℃;

s5, adding the solution C obtained in the step S3 into the solution D obtained in the step S4, reacting for 1-6h, centrifuging for 15-60min at the speed of 3000-10000r/min, cleaning the obtained precipitate for 2-5 times, drying for 6-24h at the temperature of 60-120 ℃, and grinding to obtain the copper oxide/zinc oxide composite nano-particles.

2. The antibacterial and mildewproof agent according to claim 1, wherein the copper content of the antibacterial and mildewproof agent is 2 to 6 percent.

3. The antibacterial and antifungal agent according to claim 2, wherein the amount of copper doped in the antibacterial and antifungal agent is 4%.

4. The antibacterial and antifungal agent according to any one of claims 1 to 3, wherein the particle size of the antibacterial and antifungal agent is 50 to 100 nm.

5. The method for producing the antibacterial mildewcide according to any one of claims 1 to 4, comprising:

6. The preparation method according to claim 5, wherein the copper salt is selected from one or more of copper sulfate and copper chloride; the zinc salt is selected from one or more of zinc nitrate, zinc acetate, zinc sulfate and zinc chloride.

7. The production process according to claim 5 or 6, wherein the weight ratio of the sodium lauryl sulfate to the sum of the weight of the copper salt and the zinc salt in the reaction system is 0.1 to 5: 1.

8. The method according to claim 7, wherein the weight ratio of the sodium lauryl sulfate added to the sum of the weight of the copper salt and the weight of the zinc salt in the reaction system is 1 to 3: 1.

9. An antimicrobial mildewcide made by the method of any one of claims 5 to 8.

10. Use of the antimicrobial mildewcide according to any one of claims 1 to 4 and 9 for antimicrobial and mildewproofing a material.