CN111559926B

CN111559926B - Antibacterial material based on silicate-based surface and preparation method thereof

Info

Publication number: CN111559926B
Application number: CN202010677493.8A
Authority: CN
Inventors: 彭虎
Original assignee: Guangdong Dandelion New Materials Co ltd
Current assignee: Guangdong Dandelion New Materials Co ltd
Priority date: 2020-07-15
Filing date: 2020-07-15
Publication date: 2020-10-27
Anticipated expiration: 2040-07-15
Also published as: CN111559926A

Abstract

The invention provides a preparation method of an antibacterial material based on a silicate-based surface, which comprises the steps of manufacturing a substrate with a surface with high surface energy, spraying an inorganic salt solution, spraying a reducing solution, reacting and cleaning. The invention also discloses an antibacterial material based on the surface of the silicate matrix, which is obtained by the method, the preparation process is simple, the process parameters are easy to control, and the antibacterial performance of the obtained antibacterial material is good.

Description

Antibacterial material based on silicate-based surface and preparation method thereof

Technical Field

The invention relates to the technical field of antibacterial materials, in particular to a preparation method of an antibacterial material based on the surface of a silicate matrix and the antibacterial material.

Background

With the scientific progress and the improvement of the living standard, the demands of people on the health and the healthy environment are increased day by day; pathogenic bacteria such as bacteria and mold are harmful to human beings, animals and plants, and are important factors affecting human health. Therefore, antibacterial materials and products are the focus of increasing attention, and inorganic antibacterial materials and products are always favored by the market due to the characteristics of harmlessness and safety.

In inorganic antibacterial materials, the commonly used antibacterial components are three metals of silver, copper and zinc, wherein the silver effect is the most obvious; copper is used as heavy metal, and the factors and application considering the environmental influence are limited to a certain extent; silver is a precious metal, and is expensive, so that the popularization of silver-based antibacterial materials is limited due to the production cost.

Ceramics are an important classification of silicates, the oldest and inherited products in China, and the most frequent contact with human beings is achieved; people also carry out deep research on the research and development of ceramic antibacterial materials, but the research direction is mostly focused on adding inorganic antibacterial materials into ceramic matrix raw materials and glaze raw materials and then preparing the ceramic antibacterial materials by sintering; however, in this way, the inorganic antibacterial material generates a new phase during firing and is wrapped by the glass phase of the fired layer, and the antibacterial effect is greatly reduced.

Chinese patent publication No. CN 111056862A discloses a process for producing an antibacterial ceramic tile, which is characterized in that an antibacterial material containing nano-silver or nano-zinc particles is mixed with an antifouling liquid, and the antibacterial material is filled into micro-nano-grade holes and gaps on the surface of the ceramic in an extrusion manner; the antibacterial material is easy to fall off by the mechanical filling method; and a large amount of antibacterial materials and the antifouling liquid are discarded as waste liquid together, which causes waste.

Therefore, the development of a novel antibacterial material which is simple in preparation process, easy in process parameter control and good in antibacterial performance is of great significance.

Disclosure of Invention

The first purpose of the invention is to provide a preparation method of an antibacterial material based on a silicate surface, which comprises the following steps:

the method comprises the following steps of firstly, carrying out surface activation treatment, cleaning and blow-drying on the surface of a substrate to obtain the substrate with a high surface energy surface; the surface activation treatment comprises at least one of physical grinding, chemical erosion and spraying of a hydrophilic surfactant;

step two, spraying and coating an inorganic salt solution on the surface with high surface energy in the matrix obtained in the step one, standing for 1 second to 60 minutes, and drying by spraying to obtain the matrix with the sprayed and coated surface; the content of silver ions in the inorganic salt solution is 0.01-2 wt% or the content of zinc ions is 0.1-20 wt%;

step three, spraying the reducing liquid on the spraying surface of the matrix obtained in the step two, and standing for 1 second to 60 minutes;

step four, carrying out reaction and drying at the temperature of 20-200 ℃ to obtain a matrix with an antibacterial surface; wherein: the reaction is one or more of aging reaction, heating curing, microwave radiation and photocatalysis;

and step five, cleaning the antibacterial surface of the substrate in the step four to obtain an antibacterial silicate material product.

Preferably, in the above technical solution, the preparation step of the inorganic salt solution in step two is as follows:

step 2.1, mixing inorganic silver salt or inorganic zinc salt and deionized water according to the weight ratio of 1: 1-10000 mixing;

step 2.2, adding NaOH or KOH solution until complete precipitation, OH in the NaOH or KOH solution^-The molar amount of the silver ion or the zinc ion in the inorganic silver salt or the inorganic zinc salt in the step 2.1 is 1 to 2.5 times of that in the inorganic silver salt or the inorganic zinc salt;

step 2.3, adding a complexing agent into the product obtained in the step 2.2 to gradually dissolve the precipitate, wherein NH is contained in the complexing agent₄ ⁺The concentration of the ions is 0.1-5mol/l, NH⁴⁺The molar amount of ions is 1-5 times the molar amount of silver or zinc ions in the product of step 2.2.

Preferably, in the above technical scheme, the inorganic silver salt is silver nitrate or silver sulfate; the inorganic zinc salt is zinc nitrate or zinc sulfate or zinc chloride; the complexing agent is at least one of ammonia water, ethylene diamine tetraacetic acid and diethyl triamine pentaacetic acid.

Preferably, in the above technical scheme, the reducing solution in step three is prepared from a reducing agent, a stable dispersant and deionized water in a weight ratio of 1: 0.1-10: 1-10000 is prepared;

the reducing agent is at least one of trisodium citrate, ethylene diamine tetraacetic acid salt, ethylene glycol, sodium borohydride, sodium hypophosphite and ascorbic acid; the weight content ratio of the reducing reagent to the silver ions or the zinc ions in the step two is 1: 1-10;

the stabilizing dispersant is at least one of polyvinyl pyrrole 21773, ketone, polyvinyl alcohol, gelatin and aniline.

Preferably, in the above technical solution, in step four:

the aging reaction is to stand for 1 to 20 days at room temperature;

the heating and curing step is to keep the temperature constant within the temperature range of 40-200 ℃ for 1-200 minutes;

the parameters of the microwave radiation are: the microwave power density is 1-100 KW/m³The time is 1-60 minutes;

the parameters of the photocatalysis are: the light wavelength is 10 nm-10 ɥ m, the illumination intensity is 0.05 lux-1000 lux, and the illumination time is 10 seconds-100 minutes.

In the above technical scheme, preferably, the shower coating in the first step, the second step and the third step is one or more of spraying, dipping, brushing, rolling and coating.

In the above technical solution, preferably, the substrate is made of one of ceramic, stone and glass.

The preparation method of the invention has the following effects:

the material of the matrix adopted by the invention is one of ceramics, stone and glass, and the defects are known to exist in the surface of the matrix, and the defects are macroscopic and microscopic and mesoscopic; the invention utilizes an in-situ synthesis method to continuously generate nano silver or nano zinc under the non-surface continuous condition, which is attached to and deposited on the defects on the surface of a substrate and combined with the defects, and specifically comprises the following steps: the surface of a substrate is enabled to obtain a surface with high surface energy by means of physical grinding, chemical erosion, spraying of a hydrophilic surfactant and the like, an inorganic salt solution is sprayed on the surface and stands for 1 second to 60 minutes, so that silver ions or zinc ions are fully adsorbed on the surface of defects; the inorganic salt solution after being dried can be reused, and the cost is saved. And then the reducing liquid is sprayed on the surface and stands for 1 second to 60 minutes, so that the silver ions or the zinc ions are reduced into nano-scale silver particles or zinc particles and attached to and deposited on the surface of the defect. Because the reaction can not be completely carried out under the non-surface continuous condition, the reaction is promoted to be carried out or the long-time aging reaction is carried out under the action of external fields such as heat, light, electromagnetic fields and the like within the temperature range of 20-200 ℃, the growth of nano silver/zinc particles is promoted, the stability and the dispersity of the nano silver/zinc particles are improved, the combination degree of the particles and the defect surfaces is increased, the antibacterial material is not easy to fall off from a matrix, and the antibacterial performance is good.

In the preparation step of the inorganic salt solution, the complexing agent is used for complexing silver ions or zinc ions, the concentration of free silver ions or zinc ions is controlled, the reduction speed of the silver ions or zinc ions is indirectly controlled, and the purpose of controlling the particle size of nano silver or nano zinc is achieved. But too much NH₄ ⁺The ions generate ammonia gas volatilization in the subsequent reduction process,the volatilization of ammonia gas can cause adverse effects on the adsorption, deposition and combination of nano silver or nano zinc particles and the defect surface under the non-surface continuous condition, and the invention can cause adverse effects on NH₄ ⁺The addition of ions is limited and overcome by precipitation followed by dissolution of the complexing agent.

In the fourth step of the invention, in order to ensure that the nano silver or the nano zinc is continuously generated under the non-surface continuous condition, the invention carries out measures of heating and curing, microwave radiation and photocatalysis besides long-time aging reaction, and specifically comprises the following steps:

the temperature of the reduction reaction is increased by heating and curing, so that the reaction speed is increased, and a large number of experiments prove that the scheme can generate nano silver or nano zinc particles under the non-surface continuous condition.

Through microwave radiation to the substrate and the solution, positive ions, nearby negative electrons or dipole molecules in the substrate and the solution frequently rotate and vibrate in a high-frequency alternating electromagnetic field to generate heat through friction; the frequent rotation and vibration of positive ions, nearby negative electrons or dipole molecules generate the effect of molecular level 'stirring', and can also cause the surface temperature rise of nano silver or nano zinc particles to cause the crystal grain reconstruction, which are favorable for the generation and control of the nano silver or nano zinc particles and the adsorption, deposition and combination with the defect surface; too low microwave power density and too short radiation time can cause the beneficial effects not to be fully embodied; too high microwave power density and too long radiation time can also cause adverse effects such as too fast production of nano silver or nano zinc particles, too large particle size, reduced dispersion degree and the like; the invention strictly controls and limits the microwave power density and the radiation time.

In the reaction process, the solution generates hydrated electrons and reductive free radicals by photocatalysis, silver ions or zinc ions can be reduced, the light wavelength, the illumination intensity and the illumination time are reasonably controlled, and the reduced nano silver or nano zinc particles have the characteristics of high dispersibility, high stability and uniform granularity and are favorable for adsorption, deposition and combination with the surface of a defect.

Therefore, the step four can also realize the adsorption, deposition and combination of the nano silver or nano zinc particles and the defect surface by adopting any combination of the modes, thereby improving the antibacterial effect.

The spraying mode of one or more of spraying, dipping, brushing, roller coating and coating adopted by the invention is easy to realize and is beneficial to large-scale production.

It should be noted that high surface energy surfaces are unstable and over time, the reduction in surface energy eventually loses its effect through recombination and interaction of surface atoms or adsorption to other molecules or atoms around them; therefore, step two and step three must be completed within 5 hours.

The invention also discloses an antibacterial material based on the silicate base surface, the antibacterial ceramic material is prepared by the preparation method, the preparation process is simple, the process parameters are easy to control, and the antibacterial performance of the obtained antibacterial material is good.

In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail with reference to examples.

Detailed Description

The following detailed description is given with reference to examples, but the invention can be implemented in many different ways as defined and covered by the claims.

In the examples below, the chemical reagents were purchased from Yufeng glass instruments, Inc. of Changsha, and the microwave oven was provided by Chuannan, Kogaku industries, Inc.

Example 1:

a preparation method of an antibacterial material based on the surface of a silicate matrix specifically comprises the following steps:

1. base material: glazed surface of ceramic floor tile

2. Preparation of the solution

Mixing 0.2 g of silver sulfate with 10mL of deionized water, dripping 1.3mL of 0.5mol/l KOH solution to generate precipitate, and dripping NH⁴⁺3mL of mixed solution of ammonia water with ion concentration of 0.5mol/l and EDTA until precipitation is completedCompletely dissolving; deionized water is added to prepare silver ions into a silver salt solution with the concentration of 0.5 wt%.

Preparing polyvinylpyrrolidone PVP, trisodium citrate and deionized water into a reducing solution, wherein the reducing solution comprises the following components in percentage by weight: the concentration of PVP was 1wt% and the concentration of trisodium citrate was 0.1 wt%.

The preparation method of the embodiment specifically comprises the following steps:

step one, polishing (physical grinding) a ceramic tile glaze, cleaning, and wiping the glaze with ethanol (spraying a hydrophilic surfactant); obtaining a glaze surface with high surface energy after polishing and ethanol wiping;

coating the glaze with the silver salt solution, standing for 90 seconds, taking out and draining residual liquid;

step three, coating the reducing solution on the glaze surface, and standing for 30 seconds;

step four, placing the ceramic tile in a microwave oven for microwave irradiation, controlling the temperature to be 45-50 ℃ and the power density to be 15KW/m³And (3) irradiating for 20 minutes by using microwave, taking out and cleaning the glaze surface to obtain the ceramic tile with the antibacterial surface.

Example 2:

base material: natural marble slab

Preparing a solution:

preparing an inorganic salt solution: 5 g of zinc sulfate and 45 g of deionized water are prepared into a solution, and an excessive NaOH solution is dripped into the solution until all precipitates; filtering and cleaning the precipitate, placing the precipitate into a beaker, adding 30 g of deionized water, and dripping NH⁴⁺Ammonia water solution with the ion concentration of 1mol/l is added until the precipitate is just completely dissolved; deionized water was added to make the zinc ion concentration 2wt% to obtain solution A.

Preparation of a reducing solution: preparing solution B from ethylene glycol, polyvinyl alcohol and deionized water, wherein the concentration of the polyvinyl alcohol is 5wt% and the concentration of the ethylene glycol is 2 wt%.

grinding the upper plane of the stone by a plane grinder for 1-2 mm, cleaning and air-drying;

step two, dipping the stone in the solution A, standing for 30 seconds, taking out and draining residual liquid;

step three, dipping the stone in the solution B, standing for 10 seconds, taking out and draining residual liquid;

step four, heating the stone in an electric heating box, wherein the heating mode is as follows: firstly preserving heat at 65 ℃ for 30 minutes, then preserving heat at 85 ℃ for 30 minutes, and finally preserving heat at 200 ℃ for 25 minutes;

and step five, carrying out surface cleaning to obtain the marble plate with the antibacterial surface.

Example 3

base material: glass plate

Preparing an inorganic salt solution: mixing 0.5 g of silver nitrate with 10mL of deionized water, dripping 3mL of 1mol/l NaOH solution to generate precipitate, and then dripping NH⁴⁺15mL of ammonia water and EDTA mixed solution with the ion concentration of 0.5mol/l until the precipitate is just completely dissolved; deionized water is added to prepare silver ions into a silver salt solution with the concentration of 1 wt%.

Preparation of a reducing solution: preparing PVP, aniline, ascorbic acid, ethylene glycol and deionized water into a reducing solution, wherein: the PVP concentration was 1.5wt%, the aniline concentration was 0.5wt%, the ascorbic acid concentration was 0.2wt%, and the ethylene glycol concentration was 0.02 wt%.

step one, cleaning and drying the glass surface; spraying 1wt% hydrofluoric acid solution on the cleaned glass surface (chemical erosion), standing for 10-15 seconds, and draining off residual liquid; wiping the glass surface for 2-3 times (spraying a hydrophilic surfactant) by using an ethanol/isopropanol mixed solution, wherein the volume ratio of ethanol to isopropanol is 1:1, and drying in the air after wiping;

step two, dipping the glass in a silver salt solution, and standing for 5-10 seconds;

step three, dipping the glass in a reducing solution, standing for 90 seconds, taking out and draining residual liquid;

step four, carrying out photocatalysis on the glass, wherein the light wavelength is 265nm, the illumination intensity is 500lux, the illumination time is 35-40 minutes, and the temperature is controlled to be 45-50 ℃;

and step five, carrying out surface cleaning to obtain the glass plate with the antibacterial surface.

Example 4

base material: glazed tile

Preparing an inorganic salt solution: preparing a silver ammonia solution with silver ion concentration of 0.6 wt%.

Preparation of a reducing solution: preparing a reducing solution containing trisodium citrate with the concentration of 0.5wt%, sodium borohydride with the concentration of 0.1wt% and PVP with the concentration of 4 wt%.

step one, cleaning the glazed ceramic tile, soaking the glazed ceramic tile in 20wt% NaOH solution for 5-6 minutes (chemical corrosion), cleaning again and then air-drying;

secondly, roller-coating a silver-ammonia solution on the surface of the glazed ceramic tile, and standing for 5-10 seconds;

thirdly, spraying the reducing liquid on the surface of the glazed ceramic tile;

step four, naturally aging for 15 days at room temperature;

and step five, cleaning the surface to obtain the glazed ceramic tile with the antibacterial surface.

Examples 5 to 10:

examples 5-10 were conducted in a similar manner to examples 1-4, with specific parameters as set forth in Table 1 and properties as set forth in Table 2.

Comparative example 1:

base material: glazed surface of ceramic floor tile

Polishing a glaze surface until the glossiness is 60 ℃, cleaning and drying;

and secondly, extruding the nano antibacterial antifouling liquid onto the glaze surface through a grinding tool, rotating the grinding head at a speed of 50r/s, applying a pressure of 60Pa on the glaze surface by the grinding head, and waxing until the glossiness of the glaze surface is 93 degrees to obtain a sample of the comparative example 1.

Wherein: the nano antibacterial antifouling liquid is prepared by mixing ordinary g of A30 ceramic antifouling liquid and nano antibacterial slurry, wherein the weight ratio of the nano antibacterial antifouling liquid to the nano antibacterial slurry is 100: 35; the nano antibacterial slurry is prepared by mixing and grinding nano zinc oxide, 1wt% of HTK5040 dispersant and water, wherein the mass fraction of zinc ions in the nano antibacterial slurry is 4%, and the solid content is 40%. See table 2 for properties.

Comparative example 2:

ordinary glazed ceramic floor tiles are purchased in the market, and the samples of the comparative example 2 are obtained after cleaning and air drying, and the properties are shown in the table 2.

Comparative example 3:

the antibacterial glazed ceramic floor tile is purchased in the market, and the glaze is fired by glaze containing nano silver; after washing and air drying, the sample of comparative example 3 was obtained with the properties shown in Table 2.

The cleaning in the scheme is a conventional method for removing dirt or residues on the surface of an object by using deionized water and alcohol.

TABLE 1 statistical tables of parameters for examples 1-10 and comparative examples 1-3

TABLE 2 statistical tables of Properties of examples 1-10 and comparative examples 1-3

As can be seen from table 2:

1. as can be seen from examples 1 to 10, the antibacterial rate of the antibacterial material obtained by the scheme of the invention reaches above 92.37%, and is obviously improved compared with the prior art (comparative examples 1 to 3).

2. Combining examples 1-10 and comparative examples 1-3, it can be seen that the antibacterial material obtained by the scheme of the present invention has an antibacterial durability of 87.04% or more, wherein the silver ion concentration of example 10 is 5%, which is greater than the upper limit of the concentration of 2% of the present invention, and all performance indexes are lower than the levels of examples 1-9, which indicates that an excessively high silver ion concentration cannot achieve a better effect. Therefore, by adopting the scheme of the invention, the nano silver or nano zinc is continuously generated by using the in-situ synthesis method under the non-surface continuous condition, is attached to and deposited on the defects on the surface of the substrate, the nano silver/zinc particles have good stability and good combination degree with the surfaces of the defects, and the antibacterial material is not easy to fall off from the substrate and has good antibacterial performance.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A preparation method of an antibacterial material based on the surface of a silicate matrix is characterized by comprising the following steps:

step one, carrying out surface activation treatment on the surface of a substrate to obtain the substrate with a high surface energy surface; the surface activation treatment is at least one of physical grinding and chemical erosion;

step two, spraying an inorganic salt solution on the surface with high surface energy in the matrix obtained in the step one, and standing for 1 second to 60 minutes to obtain the matrix with the sprayed surface; the content of silver ions in the inorganic salt solution is 0.01-2 wt% or the content of zinc ions is 0.1-20 wt%; the preparation steps of the inorganic salt solution are as follows:

step 2.3, adding a complexing agent into the product of step 2.2 to gradually dissolve the precipitateNH in the complexing agent₄ ⁺The concentration of the ions is 0.1-5mol/l, NH₄ ⁺The molar amount of the ions is 1 to 5 times that of the silver ions or the zinc ions in the product of step 2.2;

step four, carrying out reaction at the temperature of 20-200 ℃ to obtain a substrate with an antibacterial surface; the reaction is one or more of aging reaction, heating curing, microwave radiation and photocatalysis;

step five, cleaning the antibacterial surface of the substrate in the step four to obtain an antibacterial silicate material product;

and after the substrate with the surface with high surface energy is obtained in the first step, the inorganic salt solution in the second step is subjected to flow coating and the reducing solution in the third step is subjected to flow coating within 5 hours.

2. The production method according to claim 1, wherein the inorganic silver salt is silver nitrate or silver sulfate; the inorganic zinc salt is zinc nitrate or zinc sulfate or zinc chloride; the complexing agent is at least one of ammonia water, ethylene diamine tetraacetic acid and diethyltriamine pentaacetic acid.

3. The preparation method according to claim 1, wherein the reducing solution in step three is prepared from a reducing agent, a stabilizing dispersant and deionized water in a weight ratio of 1: 0.1-10: 1-10000 is prepared;

4. The process according to any one of claims 1 to 3, wherein in step four:

the aging reaction is to stand for 1 to 20 days at room temperature;

the parameters of the photocatalysis are: the light wavelength is 10 nm-10 um, the illumination intensity is 0.05-1000 Lux, and the illumination time is 10 seconds-100 minutes.

5. The preparation method according to claim 1, wherein the curtain coating in the first step, the second step and the third step is one or more of spraying, dipping, brushing, rolling and coating.

6. The method according to claim 1, wherein the substrate is made of one of ceramic, stone and glass.

7. An antibacterial material based on the surface of a silicate matrix, characterized in that the antibacterial ceramic material is prepared by the preparation method of any one of claims 1 to 6.