CN112940591A

CN112940591A - High-performance antibacterial powder coating and preparation method thereof

Info

Publication number: CN112940591A
Application number: CN202110352110.4A
Authority: CN
Inventors: 王雄
Original assignee: Guangxi Fubaoxin Technology Co ltd
Current assignee: Guangxi Fubaoxin Technology Co ltd
Priority date: 2021-03-31
Filing date: 2021-03-31
Publication date: 2021-06-11

Abstract

The invention discloses a high-performance antibacterial powder coating and a preparation method thereof, wherein the high-performance antibacterial powder coating comprises the following raw materials in percentage by mass: 37.6 to 40.2 percent of modified coal ash, 51.4 to 53.7 percent of polyester resin, 3.4 to 4.5 percent of curing agent, 0.9 to 1.4 percent of flatting agent, 0.4 to 0.7 percent of defoaming agent, 0.6 to 1 percent of brightener and 0.3 to 0.5 percent of pigment, wherein the high-performance antibacterial powder coating is prepared by the steps of mixing raw materials, melt extrusion, grinding, crushing and the like. The antibacterial powder coating prepared by the invention has excellent performance and low production cost, and can be widely applied to the fields of door industry, aluminum profiles, medical instruments, fitness equipment, household appliances and the like.

Description

High-performance antibacterial powder coating and preparation method thereof

[ technical field ] A method for producing a semiconductor device

The invention belongs to the technical field of powder coating preparation, and particularly relates to a high-performance antibacterial powder coating and a preparation method thereof.

[ background of the invention ]

Along with the improvement of the living standard of people, domestic waste slag becomes stumbling stones which influence the living quality of people, particularly furnace slag, coal slag and the like are daunting for people, coal slag becomes one of pollution sources of the environment, meanwhile, at present, all the waste limestone slag, coal slag and the like of various factories and mines are taken as waste materials to be discharged in the environment, the waste limestone slag, the coal slag and the like are accumulated like a mountain, the environment is seriously polluted, and the cost is quite high and the time and the labor are wasted when the factory and the mine are required to be treated.

Main component SiO of coal ash₂、Al₂O₃、Fe₃O₄And FeO, and a small amount of CaO, MgO and the like, so that the coal ash surface contains a large amount of hydroxyl groups, and if the unmodified coal ash is directly filled into the coating, the agglomeration effect in the matrix of the coal ash cannot be reduced, so that the caking property, the compatibility and the wettability between the unmodified coal ash and other raw materials of the powder coating, such as resin, are extremely poor, the apparent property and the gloss of the prepared powder coating are poor, the weather resistance is not high, and the application requirement of the powder coating cannot be met.

Along with the continuous improvement of the living standard of people, the requirements of people on the living and sanitary quality are higher and higher, and the challenge of people on modern life is how to effectively resist bacteria and remove bacteria. The antibacterial coating industry is still in the development stage at present, and the application process of the antibacterial material in the coating is a common subject in the coating industry.

Chinese patent application document "a wear-resistant waterproof antibacterial powder coating" (publication number: CN105368274A) "discloses an antibacterial powder coating, which comprises the following components in parts by weight: 100 parts of polyester resin, 20-35 parts of novolac epoxy resin, 5-15 parts of polyurethane, 3-10 parts of polyvinylidene fluoride, 5-20 parts of cerium hydroxide, 10-30 parts of modified nano titanium dioxide, 5-15 parts of talcum powder, 2-8 parts of carbon nano tube, 3-6 parts of zinc powder, 2-6 parts of silicon nitride, 2-8 parts of nano zirconium oxide, 1-5 parts of barium sulfate, 2-4 parts of titanium dioxide, 3-5 parts of phenolic resin, 2-5 parts of flatting agent, 2-3.5 parts of aminosilane coupling agent, 0.5-2 parts of zinc isooctanoate, 1-2.5 parts of calcium naphthenate, 2-8 parts of hydroxyl silicone oil, 3-10 parts of dodecafluoroheptyl glycidyl ether, 0.2-1 part of dihydrazide and 0.1-0.5 part of octyl isothiazolinone. The wear-resistant waterproof antibacterial powder coating provided by the invention has good wear resistance and waterproofness, but low antibacterial performance and poor weather resistance.

At present, most of coal ash is directly used as a filler to be directly applied to paint preparation without modification, for example, Chinese patent application documents 'a modified municipal sludge casting paint and a manufacturing method thereof (publication number: CN 104475670A)' and 'a dilute silicon composite heat-insulating paint (publication number: CN 1148072A)', have the problems that: firstly, the filling amount is less, and the cost cannot be effectively reduced; secondly, the problems of too much application filling amount, poor weather resistance, low mechanical property and the like exist. How to creatively apply the coal ash in the powder coating solves the problems of high production cost of the powder coating, environmental pollution caused by the coal ash and the like, thereby realizing the industrial and industrialized application of the coal ash and having important economic and environmental benefits.

[ summary of the invention ]

The invention provides a high-performance antibacterial powder coating and a preparation method thereof, and aims to solve the problems of high production cost of the powder coating and the like.

In order to solve the technical problems, the invention adopts the following technical scheme:

a high-performance antibacterial powder coating comprises the following raw materials in percentage by mass: 37.6 to 40.2 percent of modified coal ash, 51.4 to 53.7 percent of polyester resin, 3.4 to 4.5 percent of curing agent, 0.9 to 1.4 percent of flatting agent, 0.4 to 0.7 percent of defoaming agent, 0.6 to 1 percent of brightener and 0.3 to 0.5 percent of pigment.

Further, the high-performance antibacterial powder coating comprises the following raw materials in percentage by mass: 39.8 percent of modified coal ash, 52.9 percent of polyester resin, 4.3 percent of curing agent, 1.1 percent of flatting agent, 0.6 percent of defoaming agent, 0.9 percent of brightener and 0.4 percent of pigment.

Further, the polyester resin is a CRYLCOAT 2437-2 polyester resin.

Further, the curing agent is a TGIC curing agent.

Further, the leveling agent is a leveling agent GLP 588.

Further, the defoaming agent is TP-39 defoaming agent.

Further, the brightener is brightener LD-608.

Further, the pigment is transparent blue.

Further, the preparation method of the modified coal ash comprises the following steps:

the method comprises the following steps: washing the coal ash with hydrochloric acid with the mass concentration of 25.2-30% until the pH value of the coal ash is 8.6-9.0, then washing the washed coal ash with water, detecting the pH value of the washed coal ash to be 7.2-7.5, and performing filter pressing treatment to obtain clean coal ash, wherein the clean coal ash is dried at the temperature of 70-76 ℃ until the water content is less than or equal to 2.3%;

step two: grinding the clean coal ash obtained in the step one, and sieving to obtain clean coal ash with the particle size of more than 400 meshes;

step three: adding a first compound modifier into the clean coal ash obtained in the step two, wherein the first compound modifier consists of coconut oil fatty acid diethylamide, hexa-polyglycerol monostearate and N-oleoyl-N-methyl sodium taurate, the adding amount of the first compound modifier is 4.2-4.8% of the mass of the clean coal ash, the mass ratio of the coconut oil fatty acid diethylamide to the hexa-polyglycerol monostearate to the N-oleoyl-N-methyl sodium taurate is 3.6-4.3:1:7.1-9.2, stirring for 1-1.5 hours at the microwave power of 100-200W and the rotation speed of 300-500r/min at the temperature of 60-64 ℃ to obtain a first mixture;

step four: adding the first mixture prepared in the step three, the second composite modifier and methyl ethyl ketone peroxide into a mixer, the second composite modifier consists of 2-methyl-5-vinylpyridine, lauroyl sulfate deacetylated chitosan and trihydroxy triethylamine, the adding amount of the second composite modifier is 2.3-3% of the mass of the clean coal ash, the addition amount of the methyl ethyl ketone peroxide is 0.4 to 0.5 percent of the mass of the clean coal ash, the mass ratio of the 2-methyl-5-vinylpyridine to the lauroyl sulfate chitosan to the trihydroxy triethylamine is 1:2.1-3.4:5.3-7.8, stirring for 2-3h at the microwave power of 150-;

step five: and (3) drying the second mixture prepared in the fourth step at the temperature of 58-62 ℃ until the water content is less than or equal to 1.2%, grinding the dried second mixture into powder, and sieving the powder to obtain the modified coal ash with the particle size of more than 400 meshes.

The invention also provides a preparation method of the high-performance antibacterial powder coating, which comprises the following steps:

a. mixing raw materials: mixing the raw materials according to the mass percentage, respectively adding the raw materials into a mixer, pre-crushing, and then mixing to obtain uniformly mixed raw materials;

b. melt extrusion: b, putting the uniformly mixed raw materials prepared in the step a into an extruder, performing melt extrusion, tabletting and cooling, and then crushing into sheet materials;

c. grinding and crushing: and c, placing the crushed sheet materials in the step b into a flour mill for milling, and obtaining the high-performance antibacterial powder coating after cyclone separation and screening.

The technical principle of the invention is as follows: the coal ash is powder formed after coal combustion, and the main component of the coal ash is SiO₂、Al₂O₃、Fe₃O₄FeO, a small amount of CaO, MgO and the like, and the hardness of the materials is higher, so that the scratch resistance of the prepared powder coating is better, and the manufacturing cost of the powder coating can be effectively reduced by using the waste coal ash.

The composite system of polyester resin and filler (coal ash) as main raw materials for preparing the high-performance antibacterial powder coating is a macroscopically inhomogeneous system and is a two-phase system, namely a multi-component system consisting of a dispersed phase taking the filler (coal ash) as a component and a continuous phase taking the resin as a matrix, and the influence on the bonding strength between the two phases is the interaction between chemical components on the resin microstructure (coal ash) and chemical components on a resin interface. Therefore, the key point for improving the performance of the antibacterial powder coating is to research the interaction of each component in the interface structure and the area of the antibacterial powder coating system, and the interaction between two phases is carried out through intermolecular force, polarity and the like between different substances, and the acting force can be influenced by the orientation of resin molecular chains and the dispersion degree of fillers in a matrix in the antibacterial powder coating system. The binding of fillers to resins in antibacterial powder coating systems can generally be classified into the following categories: (1) pure mechanical mixing; (2) the two phases are relatively uniformly physically mixed; (3) the two phases form a new chemical bond through chemical reaction, so that the bonding strength is greatly increased. Since polyester resin exhibits hydrophobicity and carbon ash has SiO as a main component₂、Al₂O₃、Fe₃O₄FeO, and small amounts of CaO and MThe coal ash is alkaline and has strong hydrophilic performance due to the gO and the like, and if the coal ash and the polyester resin are simply and physically mixed, the combination of two phase interfaces is necessarily weak, the compatibility is not high, the coal ash is agglomerated, the defect part of the material is easy to break under the condition of stress concentration, and the weather resistance is extremely poor, so that the coal ash needs to be subjected to surface treatment.

In order to improve the cohesiveness, compatibility and wettability between the coal ash and other raw materials of the powder coating, such as resin, the coconut oil fatty acid diethylamide, the hexa-polyglycerol monostearate and the N-oleoyl-N-methyl sodium taurate are adopted to modify the surface of the coal ash, and the modification of the coconut oil fatty acid diethylamide, the hexa-polyglycerol monostearate and the N-oleoyl-N-methyl sodium taurate play a synergistic role, so that the apparent performance and the gloss of a coating film of the high-performance antibacterial powder coating are improved in a synergistic manner; this is:

the polyester resin is non-polar, and the unmodified coal ash is alkaline, has a large amount of hydroxyl on the surface, and has a complex result, so that the high-performance antibacterial powder coating prepared by directly filling the unmodified coal ash into the polyester resin has poor apparent performance and gloss of a coating film. The coal ash is subjected to surface modification by coconut oil fatty acid diethylamide, hexapolyglycerol monostearate and N-oleoyl-N-methyl sodium taurate under certain microwave and temperature, and because the coconut oil fatty acid diethylamide, the hexapolyglycerol monostearate and the N-oleoyl-N-methyl sodium taurate contain amide, long-carbon-chain fatty acid, carbonyl, sulfonic group and other groups, amide, long-carbon-chain fatty acid, carbonyl, sulfonic group and other groups can be introduced into the surface of coal ash particles during the first modification, not only can the processing fluidity and the dispersibility of the modified coal ash be improved, but also the modified coal ash is changed from hydrophilicity to lipophilicity, and other raw materials of the modified coal ash and the high-performance antibacterial powder coating are better in cohesiveness, wettability and compatibility, and the interfacial cohesive force of the high-performance antibacterial powder coating is improved, further improving the apparent performance and the gloss of the coating film of the high-performance antibacterial powder coating.

The 2-methyl-5-vinylpyridine, lauroyl sulfate chitosan and trihydroxy triethylamine are adopted to play a synergistic role in the modification of coal ash, so that the antibacterial rate of the powder coating is improved, and the antibacterial rate is as follows:

after the coal ash is modified for the first time, 2-methyl-5-vinylpyridine, lauroyl sulfate deacetylated chitosan and trihydroxy triethylamine are adopted for carrying out secondary modification, and the 2-methyl-5-vinylpyridine, the lauroyl sulfate deacetylated chitosan and the trihydroxy triethylamine contain groups such as pyridyl and amino, so that antibacterial groups such as pyridyl and amino can be introduced to the surface of coal ash particles during secondary modification, under the mutual cooperation of the components, the antibacterial components are contacted with staphylococcus aureus and then adsorbed to the surface of the bacteria to penetrate cell walls, the composition of cell membranes is disturbed through the change of osmotic pressure and the decomposition of organic matters, the leakage of intracellular substances (DNA and RNA) is promoted, and the staphylococcus aureus can be effectively killed. In addition, the introduced antibacterial groups such as pyridyl, amino and the like are concentrated on the surface of the coal ash, so that the concentration is increased, the sterilization time is shortened, and the effect is effectively improved.

The polyester resin used in the invention is a carboxyl functional polyester resin without TMA, and the prepared high-performance antibacterial powder coating has good leveling property, adhesive force, adhesive property and weather resistance.

The TGIC curing agent used in the invention has good heat resistance, fluidity, weather resistance and adhesion, excellent high-temperature performance, good decorative performance and overbaking yellowing resistance.

The flatting agent GLP588 used in the invention can promote the coating to form a flat, smooth and uniform coating film in the drying film-forming process, can effectively reduce the surface tension of the finishing liquid, improve the leveling property and uniformity of the coating liquid, improve the permeability of the finishing liquid, reduce the possibility of generating spots and stains during brushing, increase the coverage property and enable the film to be formed uniformly and naturally.

The high-performance antibacterial powder coating is easy to generate bubbles in the production and use processes, a large number of stable bubbles are not beneficial to smooth production of the coating and the coating effect and performance of the coating, and the TP-39 defoaming agent used in the invention mainly has two functions: 1. suppressing the generation of bubbles; 2. accelerating the destruction of the generated bubbles. Thus, defoaming effect can be achieved.

The brightener LD-608 used in the invention can improve the wettability of polyester resin to pigment and modified coal ash, simultaneously avoid the defects of coating such as pinholes, shrinkage cavities and the like, play a role in helping leveling, and obviously improve the appearance of the coating, thereby enabling the coating to obtain better flatness and gloss.

The invention has the following beneficial effects:

(1) the waste coal ash can realize the purposes of changing waste into valuable and comprehensively utilizing, and provides a new way for preparing the high-performance antibacterial powder coating by utilizing the effective components in the coal ash, so that the waste coal ash is effectively utilized, and the industrial and industrialized application of the coal ash is realized.

(2) Compared with the powder coating prepared by unmodified coal ash, the high-performance antibacterial powder coating prepared by the modified coal ash has the advantages that the apparent performance of a coating film is improved, and the gloss is improved by at least 128.7 percent.

(3) The impact resistance of the high-performance antibacterial powder coating is 65.6-71.3kg/cm, which is at least 16.3 percent higher than that of the prior art; the adhesion is 0 grade, which is equivalent to the prior art; the antibacterial rate is 99.08% -99.36%, which is at least 21.5% higher than the prior art; the salt spray resistance is 659-702h, which is at least improved by 28.7 percent compared with the prior art; the humidity and heat resistance is 1124-1305h, which is at least 18.2 percent higher than that of the prior art; the artificial weather aging resistance is 1047-1158h, which is at least increased by 33.4 percent compared with the prior art; therefore, the high-performance antibacterial powder coating has excellent performance which is superior to the prior art, and can be widely applied to the fields of door industry, aluminum profiles, medical appliances, fitness equipment, household appliances and the like.

(4) According to the invention, after the coal ash is modified, the problem of poor weather resistance of the powder coating obtained by using the traditional coal ash as the filler is effectively solved, the modified coal ash is used as the filler to be filled into the prepared high-performance antibacterial powder coating, the filling amount is up to more than 37.6%, and compared with the conventional fillers such as titanium dioxide, the modified coal ash has good filling performance and can effectively reduce the production cost.

(5) When the filling amount of the modified coal ash is 39.8 percent, the comprehensive performance of the high-performance antibacterial powder coating is optimal, wherein the impact resistance is 70.2kg/cm, the adhesion is 0 grade, the antibacterial performance reaches 99.36 percent, the salt spray resistance is 702h, the humidity and heat resistance is 1305h, and the artificial weather aging resistance is 1158h, which provides a basis for seeking the optimal production process of the high-performance antibacterial powder coating.

[ description of the drawings ]

FIG. 1 is a black and white image of a high performance antibacterial powder coating product according to the most preferred embodiment 1 of the present invention.

[ detailed description ] embodiments

In order to facilitate a better understanding of the invention, the following examples are given to illustrate, but not to limit the scope of the invention.

In an embodiment, the high-performance antibacterial powder coating comprises the following raw materials in percentage by mass: 37.6 to 40.2 percent of modified coal ash, 51.4 to 53.7 percent of polyester resin, 3.4 to 4.5 percent of curing agent, 0.9 to 1.4 percent of flatting agent, 0.4 to 0.7 percent of defoaming agent, 0.6 to 1 percent of brightener and 0.3 to 0.5 percent of pigment.

The polyester resin is CRYLCOAT 2437-2 polyester resin.

The curing agent is TGIC curing agent.

The leveling agent is a leveling agent GLP 588.

The defoaming agent is TP-39 defoaming agent.

The brightener is brightener LD-608.

The pigment is transparent blue.

The preparation method of the modified coal ash comprises the following steps:

The preparation method of the high-performance antibacterial powder coating comprises the following steps:

a. mixing raw materials: mixing the raw materials according to the mass percentage, respectively adding the raw materials into a mixing machine, pre-crushing for 1min, and then mixing for 4min to obtain uniformly mixed raw materials;

b. melt extrusion: b, putting the uniformly mixed raw materials prepared in the step a into an extruder, performing melt extrusion, tabletting and cooling, and then crushing into sheet materials, wherein the melt extrusion temperature is 105-110 ℃, and the temperature in the area I is 105 ℃ and the temperature in the area II is 110 ℃;

c. grinding and crushing: and c, placing the crushed sheet materials in the step b into an ACM (Acetobacter caldron) pulverizer for pulverizing, and performing cyclone separation and screening to obtain the high-performance antibacterial powder coating with the average particle size of 30.2-38.4 mu m.

In order to further illustrate the present invention and make the disclosure more complete, more specific embodiments are described below.

EXAMPLE 1

A high-performance antibacterial powder coating comprises the following raw materials in percentage by mass: 39.8 percent of modified coal ash, 52.9 percent of polyester resin, 4.3 percent of curing agent, 1.1 percent of flatting agent, 0.6 percent of defoaming agent, 0.9 percent of brightener and 0.4 percent of pigment.

The polyester resin is CRYLCOAT 2437-2 polyester resin.

The curing agent is TGIC curing agent.

The leveling agent is a leveling agent GLP 588.

The defoaming agent is TP-39 defoaming agent.

The brightener is brightener LD-608.

The pigment is transparent blue.

The preparation method of the modified coal ash comprises the following steps:

the method comprises the following steps: washing the coal ash with hydrochloric acid with the mass concentration of 27.9% until the pH value of the coal ash is 8.7, then washing the washed coal ash with water, detecting the pH value of the washed coal ash to be 7.4, and performing filter pressing treatment to obtain clean coal ash, wherein the clean coal ash is dried at the temperature of 75 ℃ until the water content is 1.6%;

step three: adding a first compound modifier into the clean coal ash prepared in the second step, wherein the first compound modifier consists of coconut oil fatty acid diethylamide, hexa-polyglycerol monostearate and N-oleoyl-N-methyl sodium taurate, the adding amount of the first compound modifier is 4.5% of the mass of the clean coal ash, the mass ratio of the coconut oil fatty acid diethylamide to the hexa-polyglycerol monostearate to the N-oleoyl-N-methyl sodium taurate is 3.9:1:8.7, and stirring is carried out for 1.1h at the microwave power of 200W and the temperature of 63 ℃ and the rotating speed of 500r/min to prepare a first mixture;

step four: adding the first mixture prepared in the third step, a second composite modifier and methyl ethyl ketone peroxide into a mixer, wherein the second composite modifier consists of 2-methyl-5-vinylpyridine, lauroyl sulfuric acid deacetylated chitosan and trihydroxy triethylamine, the addition amount of the second composite modifier is 2.7% of the mass of the clean coal ash, the addition amount of the methyl ethyl ketone peroxide is 0.42% of the mass of the clean coal ash, the mass ratio of the 2-methyl-5-vinylpyridine to the lauroyl sulfuric acid deacetylated chitosan to the trihydroxy triethylamine is 1:2.6:6.5, and stirring for 2.5 hours at the microwave power of 230W, the temperature of 108 ℃ and the rotating speed of 500r/min to prepare a second mixture;

step five: and (3) drying the second mixture prepared in the fourth step at the temperature of 60 ℃ until the water content is 1%, grinding the dried second mixture into powder, and sieving the powder to obtain the modified coal ash with the particle size of more than 400 meshes.

The modified coal ash prepared above was subjected to infrared characterization (FTIR) and electron microscopy Scanning (SEM).

Infrared characterization (FTIR): the modified coal ash is repeatedly washed by absolute ethyl alcohol and acetone, vacuum-dried and potassium bromide tabletted, and a Nicolet 67 model Fourier infrared spectrometer produced by the American Thermo Nicolet company is adopted to record the characteristic peak of the surface of the modified coal ash. Resolution of 1cm^-1The number of scans was 16.

FT-IR analysis shows that the amido, carbonyl, sulfonic acid, pyridyl, amino and other groups are successfully grafted to the surface of the coal ash particle.

Electron microscopy Scanning (SEM): the modified coal ash is filled in a resin matrix (polyester resin) to obtain a sample, the normal-temperature notch impact section of the sample is subjected to metal spraying treatment, a tungsten filament scanning electron microscope is used for observing the surface morphology, and the voltage is 20 KV. Instrument model JSM-6490LV, manufactured by Japan.

SEM analysis shows that the modified coal ash has increased compatibility with resin matrix (polyester resin), and the modified coal ash is well dispersed in the resin matrix (polyester resin).

b. melt extrusion: b, putting the uniformly mixed raw materials prepared in the step a into an extruder, performing melt extrusion, tabletting and cooling at the temperature of 105 ℃ in a region I and 110 ℃ in a region II, and crushing into tablets;

c. grinding and crushing: and c, putting the crushed sheet materials in the step b into an ACM (Acetobacter xylinum) pulverizer for pulverizing, and performing cyclone separation and screening to obtain the high-performance antibacterial powder coating with the average particle size of 34.6 mu m, wherein the black and white picture of the product is shown in figure 1.

EXAMPLE 2

A high-performance antibacterial powder coating comprises the following raw materials in percentage by mass: 38.6 percent of modified coal ash, 53.7 percent of polyester resin, 4.3 percent of curing agent, 1.2 percent of flatting agent, 0.7 percent of defoaming agent, 1 percent of brightener and 0.5 percent of pigment.

The polyester resin is CRYLCOAT 2437-2 polyester resin.

The curing agent is TGIC curing agent.

The leveling agent is a leveling agent GLP 588.

The defoaming agent is TP-39 defoaming agent.

The brightener is brightener LD-608.

The pigment is transparent blue.

The preparation method of the modified coal ash comprises the following steps:

the method comprises the following steps: washing the coal ash with hydrochloric acid with the mass concentration of 25.7% until the pH value of the coal ash is 8.6, then washing the washed coal ash with water, detecting the pH value of the washed coal ash to be 7.3, and performing filter pressing treatment to obtain clean coal ash, wherein the clean coal ash is dried at the temperature of 72 ℃ until the water content is 2.3%;

step three: adding a first compound modifier into the clean coal ash prepared in the second step, wherein the first compound modifier consists of coconut oil fatty acid diethylamide, hexa-polyglycerol monostearate and N-oleoyl-N-methyl sodium taurate, the adding amount of the first compound modifier is 4.3% of the mass of the clean coal ash, the mass ratio of the coconut oil fatty acid diethylamide to the hexa-polyglycerol monostearate to the N-oleoyl-N-methyl sodium taurate is 3.8:1:7.1, and stirring is carried out for 1.5 hours at the microwave power of 100W and the rotation speed of 300r/min at the temperature of 60 ℃ to prepare a first mixture;

step four: adding the first mixture prepared in the third step, a second composite modifier and methyl ethyl ketone peroxide into a mixer, wherein the second composite modifier consists of 2-methyl-5-vinylpyridine, lauroyl sulfuric acid deacetylated chitosan and trihydroxy triethylamine, the addition amount of the second composite modifier is 2.4% of the mass of the clean coal ash, the addition amount of the methyl ethyl ketone peroxide is 0.4% of the mass of the clean coal ash, the mass ratio of the 2-methyl-5-vinylpyridine to the lauroyl sulfuric acid deacetylated chitosan to the trihydroxy triethylamine is 1:2.4:5.8, and stirring for 2.8 hours at the microwave power of 150W, the temperature of 103 ℃ and the rotating speed of 400r/min to prepare a second mixture;

step five: and (3) drying the second mixture prepared in the fourth step at the temperature of 58 ℃ until the water content is 1.1%, grinding the dried mixture into powder, and sieving the powder to obtain the modified coal ash with the particle size of more than 400 meshes.

c. grinding and crushing: and c, placing the crushed sheet materials in the step b into an ACM (Acetobacter caldron) pulverizer for pulverizing, and performing cyclone separation and screening to obtain the high-performance antibacterial powder coating with the average particle size of 31.9 mu m.

EXAMPLE 3

A high-performance antibacterial powder coating comprises the following raw materials in percentage by mass: 40.2% of modified coal ash, 52.3% of polyester resin, 4.3% of curing agent, 1.3% of flatting agent, 0.6% of defoaming agent, 0.8% of brightener and 0.5% of pigment.

The polyester resin is CRYLCOAT 2437-2 polyester resin.

The curing agent is TGIC curing agent.

The leveling agent is a leveling agent GLP 588.

The defoaming agent is TP-39 defoaming agent.

The brightener is brightener LD-608.

The pigment is transparent blue.

The preparation method of the modified coal ash comprises the following steps:

the method comprises the following steps: washing the coal ash with hydrochloric acid with the mass concentration of 29.1% until the pH value of the coal ash is 8.9, then washing the washed coal ash with water, detecting the pH value of the washed coal ash to be 7.4, and performing filter pressing treatment to obtain clean coal ash, wherein the clean coal ash is dried at the temperature of 75 ℃ until the water content is 1.7%;

step three: adding a first compound modifier into the clean coal ash prepared in the second step, wherein the first compound modifier consists of coconut oil fatty acid diethylamide, hexa-polyglycerol monostearate and N-oleoyl-N-methyl sodium taurate, the adding amount of the first compound modifier is 4.7% of the mass of the clean coal ash, the mass ratio of the coconut oil fatty acid diethylamide to the hexa-polyglycerol monostearate to the N-oleoyl-N-methyl sodium taurate is 4.2:1:8.9, and stirring is carried out for 1.3h at the microwave power of 160W and the rotation speed of 400r/min at the temperature of 63 ℃ to prepare a first mixture;

step four: adding the first mixture prepared in the third step, a second composite modifier and methyl ethyl ketone peroxide into a mixer, wherein the second composite modifier consists of 2-methyl-5-vinylpyridine, lauroyl sulfuric acid deacetylated chitosan and trihydroxy triethylamine, the addition amount of the second composite modifier is 2.7% of the mass of the clean coal ash, the addition amount of the methyl ethyl ketone peroxide is 0.5% of the mass of the clean coal ash, the mass ratio of the 2-methyl-5-vinylpyridine to the lauroyl sulfuric acid deacetylated chitosan to the trihydroxy triethylamine is 1:2.9:6.4, and stirring for 2.6 hours at the microwave power of 250W and the rotation speed of 500r/min at the temperature of 110 ℃ to prepare a second mixture;

step five: and (3) drying the second mixture prepared in the fourth step at the temperature of 62 ℃ until the water content is 0.9%, grinding the dried mixture into powder, and sieving the powder to obtain the modified coal ash with the particle size of more than 400 meshes.

c. grinding and crushing: and c, placing the crushed sheet materials in the step b into an ACM (Acetobacter caldron) pulverizer for pulverizing, and performing cyclone separation and screening to obtain the high-performance antibacterial powder coating with the average particle size of 37.2 mu m.

Comparative example 1

The preparation process of the high-performance antibacterial powder coating is basically the same as that of example 1, except that only the modification of the fourth step is performed in the preparation of the modified coal ash, and the modification of the third step is not performed.

Comparative example 2

The high performance antibacterial powder coating was prepared by a process substantially the same as that of example 1, except that the first composite modifier used in the preparation of the modified coal ash was devoid of coconut oil fatty acid diethylamide.

Comparative example 3

The preparation process of the high performance antibacterial powder coating is basically the same as that of example 1, except that the first composite modifier used in the preparation of the modified coal ash lacks hexa-polyglycerol monostearate.

Comparative example 4

The preparation process of the high-performance antibacterial powder coating is basically the same as that of example 1, except that the first composite modifier used in the preparation of the modified coal ash lacks N-oleoyl-N-methyltaurate.

Comparative example 5

The preparation process of the high-performance antibacterial powder coating is basically the same as that of example 1, except that only the modification of the third step is performed in the preparation of the modified coal ash, and the modification of the fourth step is not performed.

Comparative example 6

The preparation process of the high performance antibacterial powder coating is basically the same as that of example 1, except that the second composite modifier used in the preparation of the modified coal ash lacks 2-methyl-5-vinylpyridine.

Comparative example 7

The preparation process of the high performance antibacterial powder coating is basically the same as that of example 1, except that the second composite modifier used in the preparation of the modified coal ash lacks lauroyl sulfated chitosan.

Comparative example 8

The preparation process of the high-performance antibacterial powder coating is basically the same as that of the example 1, except that the second composite modifier used in the preparation of the modified coal ash lacks trihydroxy triethylamine.

Comparative example 9

The preparation process of the high-performance antibacterial powder coating is basically the same as that of the example 1, except that the modified coal ash is not modified in the third step and the fourth step.

Comparative example 10

The antibacterial powder coating prepared by the process of the example 1-5 of the Chinese patent application document ' a wear-resistant waterproof antibacterial powder coating ' (publication number: CN105368274A) '.

And (3) performance detection:

preparing a coating layer: the high performance antibacterial powder coatings of examples 1-3 and comparative examples 1-4, 9 were sprayed on the surface-treated cold rolled steel sheets using an electrostatic spray gun, the thickness of the coating films was substantially uniform, and cured at 200 deg.C/10 min to obtain coating layers corresponding to examples 1-3 and comparative examples 1-4, 9, the gloss was measured using GB/T1743-1979.

The results of coating tests of examples 1 to 3 and comparative examples 1 to 4 and 9 are shown in Table 1.

TABLE 1 coating test results of examples 1-3 and comparative examples 1-4, 9

Experimental project	Apparent appearance of coating film	Gloss (60 degree specular gloss),% of
			Example 1	Smooth and pore-free	70.2
Example 2	Smooth and pore-free	66.1
			Example 3	Smooth and pore-free	68.4
Comparative example 1	Rough, unsmooth and porous	43.9
			Comparative example 2	Basically flat and smooth without air holes	61.4
Comparative example 3	Basically flat and smooth without air holes	64.3
			Comparative example 4	Basically flat and smooth without air holes	62.8
Comparative example 9	Rough, unsmooth and porous	30.7

As can be seen from Table 1: (1) as can be seen from the data of example 1 and comparative examples 1-4, coconut oil fatty acid diacetyl amide, hexa-polyglycerol monostearate and N-oleoyl-N-methyl sodium taurate play a synergistic role in coal ash modification, and the apparent performance and gloss of a coating film of the high-performance antibacterial powder coating are synergistically improved; this is:

the polyester resin is non-polar, and the unmodified coal ash is alkaline, has a large amount of hydroxyl on the surface, and has a complex result, so that the high-performance antibacterial powder coating prepared by directly filling the unmodified coal ash into the polyester resin has poor film appearance and gloss. The coal ash is subjected to surface modification by coconut oil fatty acid diethylamide, hexapolyglycerol monostearate and N-oleoyl-N-methyl sodium taurate under certain microwave and temperature, and because the coconut oil fatty acid diethylamide, the hexapolyglycerol monostearate and the N-oleoyl-N-methyl sodium taurate contain amide, long-carbon-chain fatty acid, carbonyl, sulfonic group and other groups, amide, long-carbon-chain fatty acid, carbonyl, sulfonic group and other groups can be introduced into the surface of coal ash particles during the first modification, not only can the processing fluidity and the dispersibility of the modified coal ash be improved, but also the modified coal ash is changed from hydrophilicity to lipophilicity, and other raw materials of the modified coal ash and the high-performance antibacterial powder coating are better in cohesiveness, wettability and compatibility, and the interfacial cohesive force of the high-performance antibacterial powder coating is improved, further improving the apparent performance and the gloss of the coating film of the high-performance antibacterial powder coating.

(2) As can be seen from the data of examples 1 to 3 and comparative example 9, the high performance antibacterial powder coating prepared using the modified coal ash has improved apparent coating properties and improved gloss by at least 128.7% as compared with the powder coating prepared using the unmodified coal ash.

The high performance antibacterial powder coatings prepared in examples 1-3 and comparative examples 5-8, 10 were tested for impact resistance, adhesion, antibacterial rate, salt spray resistance, humidity resistance, and artificial weather resistance, wherein the impact resistance was tested using GB/T1732-1993 ISO 6272; the adhesion is detected by GB/T9286-1998 ISO 2409; the antibacterial rate is detected by GB/T21866-2008, wherein the bacteria are staphylococcus aureus; the salt spray resistance is detected by GB/T1771-2007 ISO 7253; the humidity and heat resistance is detected by GB/T1740-2007 ISO 6270; the resistance to artificial weathering was measured using GB/T1865-1997 ASTMG151, and the results are shown in Table 2 below.

TABLE 2 tables of results of performance tests of the powder coatings obtained in examples 1 to 3 and comparative examples 5 to 8 and 10

As can be seen from Table 2:

(1) as can be seen from the data of example 1 and comparative examples 5-8, 2-methyl-5-vinylpyridine, lauroyl chitosan sulfate, trihydroxy triethylamine have a synergistic effect in the modification of coal ash, increasing the antibacterial rate of the powder coating, which is:

(2) As can be seen from the data of examples 1 to 3, the impact resistance of the high performance antibacterial powder coating of the present invention is 65.6 to 71.3kg/cm, which is improved by at least 16.3% as compared with the prior art (comparative example 10); the adhesion is 0 grade, which is equivalent to the prior art (comparative example 10); the antibacterial rate is 99.08-99.36%, which is at least 21.5% higher than that of the prior art (comparative example 10); the salt spray resistance is 659-702h, which is improved by at least 28.7 percent compared with the prior art (comparative example 10); the humidity and heat resistance is 1124-1305h, which is at least 18.2 percent higher than that of the prior art (comparative example 10); the artificial weathering resistance is 1047-1158h, which is improved by at least 33.4 percent compared with the prior art (comparative example 10); it can be seen that the high performance antibacterial powder coating of the present invention is excellent and superior to the prior art (comparative example 10).

(3) The modified coal ash is used as the filler to be filled into the prepared high-performance antibacterial powder coating, the filling amount is up to more than 37.6 percent, compared with the conventional fillers such as titanium dioxide, the modified coal ash has good filling performance and can effectively reduce the production cost (because the cost for purchasing the waste coal ash is extremely low, the waste coal ash is used as the raw material, and the modified coal ash is obtained after modification as the filler, the cost for preparing the modified coal ash filler is far less than that of the conventional filler titanium dioxide, and about 620 yuan/ton is less, so the production cost for preparing the high-performance antibacterial powder coating can be effectively reduced).

(4) From the data of examples 1-3, it can be seen that example 1 is the most preferred example, and that when the modified coal ash loading is 39.8% in example 1, the overall performance of the high performance antibacterial powder coating is the most preferred, wherein the impact resistance is 70.2kg/cm, the adhesion is 0 grade, the antibacterial performance reaches 99.36%, the salt spray resistance is 702h, the wet heat resistance is 1305h, and the artificial weather resistance is 1158h, which provides the basis for seeking the best production process of the high performance antibacterial powder coating.

The above description should not be taken as limiting the invention to the embodiments, but rather, as will be apparent to those skilled in the art to which the invention pertains, numerous simplifications or substitutions may be made without departing from the spirit of the invention, which shall be deemed to fall within the scope of the invention as defined by the claims appended hereto.

Claims

1. The high-performance antibacterial powder coating is characterized by comprising the following raw materials in percentage by mass: 37.6 to 40.2 percent of modified coal ash, 51.4 to 53.7 percent of polyester resin, 3.4 to 4.5 percent of curing agent, 0.9 to 1.4 percent of flatting agent, 0.4 to 0.7 percent of defoaming agent, 0.6 to 1 percent of brightener and 0.3 to 0.5 percent of pigment.

2. The high-performance antibacterial powder coating as claimed in claim 1, which is characterized by comprising the following raw materials in percentage by mass: 39.8 percent of modified coal ash, 52.9 percent of polyester resin, 4.3 percent of curing agent, 1.1 percent of flatting agent, 0.6 percent of defoaming agent, 0.9 percent of brightener and 0.4 percent of pigment.

3. The high performance antibacterial powder coating according to claim 1 or 2, wherein the polyester resin is a CRYLCOAT 2437-2 polyester resin.

4. The high performance antibacterial powder coating according to claim 1 or 2, wherein said curing agent is TGIC curing agent.

5. The high performance antibacterial powder coating according to claim 1 or 2, wherein the leveling agent is a leveling agent GLP 588.

6. The high performance antibacterial powder coating according to claim 1 or 2, wherein said defoaming agent is TP-39 defoaming agent.

7. The high performance antibacterial powder coating according to claim 1 or 2, wherein the brightener is brightener LD-608.

8. The high performance antibacterial powder coating according to claim 1 or 2, wherein the pigment is transparent blue.

9. The high-performance antibacterial powder coating according to claim 1 or 2, wherein the preparation method of the modified coal ash comprises the following steps:

10. A method for preparing a high performance antibacterial powder coating according to claims 1-9, characterized by comprising the following steps: