1. A preparation method of a high-hardness wear-resistant metal anticorrosive paint is characterized by comprising the following steps:

preparation of coating film-forming resin

Under the condition of stirring, adding nano silica sol into a reaction kettle, controlling the pH value of a system to be 2-6 by adding a catalyst, controlling the reaction temperature to be 30-65 ℃, dropwise adding composite siloxane into the reaction kettle, wherein the mass ratio of the composite siloxane to the nano silica sol is 1/5-3, controlling the dropwise adding time of the composite siloxane to be 6-16 h, and continuously reacting for 2-6 h after dropwise adding is finished to obtain organic silicon modified composite sol;

adding one or more of epoxy resin, phenolic resin, acrylic resin and alkyd resin into the step (1) under the condition of stirring, and carrying out reflux reaction for 2-6 h at the reaction temperature of 45-85 ℃, thus completing the preparation of the coating film-forming material resin;

(II) preparation of composite slurry

Compounding two kinds of powder of an anticorrosive pigment and a coloring pigment at room temperature, adding the powder into a charging barrel, adding a composite solvent, stirring and dispersing by using a high-speed dispersion machine, uniformly dispersing, adding a surface modifier accounting for 0.1-2% of the total mass of the powder, continuously dispersing for 10-30 min, and grinding by using a sand mill to obtain composite slurry;

(III) preparation of the coating

And (3) adding the film-forming material resin in the step (I) and the composite slurry in the step (II) into a stirrer according to the mass ratio of 1/5-5 at room temperature, stirring and mixing, adding an auxiliary agent, continuously stirring for a period of time, filtering and discharging to obtain the high-hardness wear-resistant metal anticorrosive paint.

2. The method for preparing the high-hardness wear-resistant metal anticorrosive paint according to claim 1, wherein the catalyst is an acidic catalyst or a basic catalyst for adjusting the final pH value of the organosilicon-modified composite sol; wherein the acidic catalyst is: one or more of hydrochloric acid, nitric acid, formic acid, or acetic acid; the basic catalyst is: one or more of ammonia water, sodium hydroxide and potassium hydroxide.

3. The method for preparing a high-hardness wear-resistant metal anticorrosive coating according to claim 1, wherein the composite organosilane is a tetraalkoxy organosilane, a trialkoxy organosilane, OR a mixture of dialkoxy organosilanes, and has a molecular formula of RnSi (OR') 4-n, and R is an organic functional group containing no oxygen atom and directly connected with a silicon atom.

4. The method for preparing a high-hardness wear-resistant metal anticorrosive coating according to claim 3, wherein the tetraalkoxy organosilane is tetramethoxysilane or tetraethoxysilane; the trialkoxy organosilane is methyl triethoxysilane, methyl trimethoxysilane, isobutyl trimethoxysilane, KH560 or KH 570; the dialkoxy organosilane is dimethyl dimethoxy silane, diphenyl dimethoxy silane, dimethyl diethoxy silane, diphenyl diethoxy silane, methyl phenyl dimethoxy silane or methyl phenyl diethoxy silane.

5. The method for preparing the high-hardness wear-resistant metal anticorrosive paint according to claim 1, wherein the anticorrosive pigment is one or more of zinc powder, aluminum powder, ferrophosphorus powder, zinc phosphate, zinc silicate, mica iron oxide and aluminum tripolyphosphate.

6. The method for preparing the high-hardness wear-resistant metal anticorrosive paint according to claim 1, wherein the filler is one or more of silicon carbide, aluminum oxide, barium sulfate, molybdenum disulfide, talcum powder, mica and silicon whisker.

7. The method for preparing the high-hardness wear-resistant metal anticorrosive paint according to claim 1, wherein the coloring pigment is one or more of carbon black, titanium dioxide, iron oxide red, iron oxide black, medium chrome yellow and iron oxide blue.

8. The preparation method of the high-hardness wear-resistant metal anticorrosive paint according to claim 1, wherein the composite solvent is two or more of ethanol, isopropanol, propylene glycol methyl ether and diacetone alcohol.

9. The method for preparing the high-hardness wear-resistant metal anticorrosive paint according to claim 1, wherein the surface modifier is one or more of hydroxyl silicone oil, monoalkoxy titanate, KH550, KH560 and KH 570.

10. The preparation method of the high-hardness wear-resistant metal anticorrosive paint according to claim 1, wherein the pH value of the nano silica sol is 1.5-11, and the particle size is 1-10 nm; the content of silicon dioxide in the nano silica sol is 5-50%, and the solvent is any one or more of ethanol, isopropanol, propylene glycol methyl ether and diacetone alcohol.

Background

Metal corrosion generally proceeds by two routes: chemical etching and electrochemical etching. Chemical corrosion is corrosion caused by the direct chemical reaction of a metal surface with the surrounding medium. Electrochemical corrosion is corrosion that results from the reaction of electrodes by contacting a metallic material (alloy or impure metal) with an electrolyte solution. The metal corrosion problem spreads in various fields of national economy, and huge loss is brought to the national economy. For a long time, various techniques have been used to protect metals from chemical corrosion. Among them, one of the most common methods is to apply an anti-corrosion coating on the metal surface to isolate the corrosive medium from the metal substrate.

The metal anticorrosive coating solution is an inorganic polymer chelating film forming solution, takes a siloxane-based SiOSi bond as a base, grafts an organic alkyl side chain as an assistant, and takes hydroxyl as an end chain chelating anticorrosive film forming substance, the bond has good ternary synergistic effect on the hydroxyl and alkyl connected to the silicon atom for chelating, the solution stability is strong, the influence on the inside of a high polymer is reduced, and the film forming substance is more compact, strong in adhesive force and high in temperature resistance (equivalent to the effect of a Ni-based steel material). The filler in the coating is composed of highly dispersed and activated passivated metal particles, nano graphite flakes, nano metal amphoteric oxide, ultrafine rare earth ultrafine powder and the like. The activated anti-corrosion pigments can play a role in resisting corrosion and enhancing polarization, so that the acid resistance, alkali resistance and corrosion resistance of the metal are improved.

However, the existing metal anticorrosive paint generally has the defects of low hardness and poor wear resistance, and the surface of a coating film is damaged after being rubbed for several times, so that the attractiveness of the product is reduced, and the service life of the product is shortened. The main problem of the above reasons is that most of the existing coatings are organic coatings and have poor hardness, so that further improvement on the prior art is needed.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention aims to develop an organic-inorganic hybrid three-proofing coating which has the advantages of both organic coatings and inorganic coatings and makes up the respective defects.

A preparation method of a high-hardness wear-resistant metal anticorrosive paint comprises the following steps:

preparation of coating film-forming resin

(1) Under the condition of stirring, adding nano silica sol into a reaction kettle, controlling the pH value of a system to be 2-6 by adding a catalyst, controlling the reaction temperature to be 30-65 ℃, dropwise adding composite siloxane into the reaction kettle, wherein the mass ratio of the composite siloxane to the nano silica sol is 1/5-3, controlling the dropwise adding time of the composite siloxane to be 6-16 h, and continuously reacting for 2-6 h after dropwise adding is finished to obtain organic silicon modified composite sol;

(2) adding one or more of epoxy resin, phenolic resin, acrylic resin and alkyd resin into the step (1) under the condition of stirring, and carrying out reflux reaction for 2-6 h at the reaction temperature of 45-85 ℃, thus completing the preparation of the coating film-forming material resin;

(II) preparation of composite slurry

Compounding two kinds of powder of an anticorrosive pigment and a coloring pigment at room temperature, adding the powder into a charging barrel, adding a composite solvent, stirring and dispersing by using a high-speed dispersion machine, uniformly dispersing, adding a surface modifier accounting for 0.1-2% of the total mass of the powder, continuously dispersing for 10-30 min, and grinding by using a sand mill to obtain composite slurry;

(III) preparation of the coating

And (3) adding the film-forming material resin in the step (I) and the composite slurry in the step (II) into a stirrer according to the mass ratio of 1/5-5 at room temperature, stirring and mixing, adding an auxiliary agent, continuously stirring for a period of time, filtering and discharging to obtain the high-hardness wear-resistant metal anticorrosive paint.

Preferably, the catalyst refers to an acidic catalyst or a basic catalyst for adjusting the final pH value of the organic silicon modified composite sol; wherein the acidic catalyst is: one or more of hydrochloric acid, nitric acid, formic acid, or acetic acid; the basic catalyst is: one or more of ammonia water, sodium hydroxide and potassium hydroxide

Preferably, the composite organosilane is tetraalkoxy organosilane, trialkoxy organosilane, OR a mixture of dialkoxy organosilane, and the molecular formula of the composite organosilane is RnSi (OR') 4-n, wherein R is an organic functional group which does not contain an oxygen atom and is directly connected with a silicon atom.

Preferably, the tetraalkoxy organosilane is tetramethoxysilane or tetraethoxysilane; the trialkoxy organosilane is methyl triethoxysilane, methyl trimethoxysilane, isobutyl trimethoxysilane, KH560 or KH 570; the dialkoxy organosilane is dimethyl dimethoxy silane, diphenyl dimethoxy silane, dimethyl diethoxy silane, diphenyl diethoxy silane, methyl phenyl dimethoxy silane or methyl phenyl diethoxy silane.

Preferably, the anti-corrosion pigment is one or more of zinc powder, aluminum powder, ferrophosphorus powder, zinc phosphate, zinc silicate, mica iron oxide and aluminum tripolyphosphate.

Preferably, the filler is one or more of silicon carbide, alumina, barium sulfate, molybdenum disulfide, talcum powder, mica and whisker silicon.

Preferably, the coloring pigment is one or more of carbon black, titanium dioxide, iron oxide red, iron oxide black, medium chrome yellow and iron oxide blue.

Preferably, the composite solvent is two or more of ethanol, isopropanol, propylene glycol methyl ether and diacetone alcohol.

Preferably, the surface modifier is one or more of hydroxyl silicone oil, monoalkoxy titanate, KH550, KH560 and KH 570.

Preferably, the pH value of the nano silica sol is 1.5-11, and the particle size is 1-10 nm; the content of silicon dioxide in the nano silica sol is 5-50%, and the solvent is any one or more of ethanol, isopropanol, propylene glycol methyl ether and diacetone alcohol.

The technical scheme has the following beneficial effects: according to the preparation method of the high-hardness wear-resistant metal anticorrosive paint, composite siloxane is adopted to modify nano silica sol in an acidic environment to obtain organic silicon modified composite sol, and paint film forming material resin prepared from the modified composite sol is combined with composite slurry to realize inorganic impurity of the organic paint, so that the hardness of the paint can be effectively improved, and according to detection, the hardness of the paint prepared by adopting the technology disclosed by the patent can reach 5H-6H, and is far higher than that of the existing metal anticorrosive paint.

Detailed Description

The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure. The following example embodiments may be embodied in many different forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

A preparation method of a high-hardness wear-resistant metal anticorrosive paint comprises the following steps:

preparation of coating film-forming resin

(1) Under the stirring condition of 300r/min, adding nano silica sol with the particle size into a reaction kettle, controlling the pH value of a system to be 2-6, preferably 2.5-4.5, at the reaction temperature of 30-65 ℃, then dropwise adding composite siloxane with the mass ratio of 1/5-3, controlling the dropwise adding time of the composite siloxane to be 6-16 h, preferably 8-12 h, and continuing to react for 2-6 h to obtain organic silicon modified composite sol;

(2) and (2) adding one or more of epoxy resin, phenolic resin, acrylic resin and alkyd resin into the step (1) under the stirring condition of 500r/min, and performing reflux reaction at the reaction temperature of 45-85 ℃ for 2-6 h to complete the preparation of the coating film-forming material resin.

The pH value of the nano silica sol is 1.5-11, the particle size is 1-10 nm, preferably 1-5nm, the content of silicon dioxide in the nano silica sol is 5-50%, preferably 5-20%, and the solvent is any one or more of ethanol, isopropanol, propylene glycol monomethyl ether and diacetone alcohol; the catalyst is an acidic catalyst or an alkaline catalyst for adjusting the final pH value of the organic silicon modified composite sol; wherein the acidic catalyst is: one or more of hydrochloric acid, nitric acid, formic acid, or acetic acid; the basic catalyst is: one or more of ammonia water, sodium hydroxide and potassium hydroxide. The compound organosilane refers to: tetraalkoxy organosilanes, trialkoxy organosilanes, mixtures of dialkoxy organosilanes; the molecular formula is RnSi (OR') 4-n, R is an organic functional group which does not contain an oxygen atom and is directly connected with a silicon atom, such as: alkyl, aryl, gamma-glycidoxypropyl, gamma-methacryloxypropyl; r' is C1-C5 alkyl, and n is 0, 1 or 2; n-0 is tetraalkoxy organosilane, n-1 is trialkoxy organosilane, and n-2 is dialkoxy organosilane.

Preferably, the tetraalkoxy organosilane is tetramethoxysilane or tetraethoxysilane; the trialkoxy organosilane is methyl triethoxysilane, methyl trimethoxysilane, isobutyl trimethoxysilane, KH560 or KH 570; the dialkoxy organosilane is dimethyldimethoxysilane, diphenyldimethoxysilane, dimethyldiethoxysilane, diphenyldiethoxysilane, methylphenyldimethoxysilane or methylphenyldiethoxysilane.

(II) preparation of composite slurry

Compounding an anticorrosive pigment, a coloring pigment and a filler at room temperature, adding the mixture into a charging barrel, adding a composite solvent, stirring and dispersing by using a high-speed dispersion machine, controlling the stirring speed to be 1000-1500 rpm, adding one or more surface modifiers accounting for 0.1-2% of the total mass of powder after uniform dispersion, continuously dispersing for 10-30 min, grinding the composite slurry by using a sand mill, controlling the temperature of a cavity of the sand mill to be 3-6 ℃, and grinding for 1-4 h to finish the preparation of the composite slurry.

The anti-corrosion pigment is one or more of zinc powder, aluminum powder, ferrophosphorus powder, zinc phosphate, zinc silicate, mica iron oxide and aluminum tripolyphosphate. The filler is one or more of silicon carbide, alumina, barium sulfate, molybdenum disulfide, talcum powder, mica and crystal whisker silicon. The coloring pigment is one or more of carbon black, titanium dioxide, iron oxide red, iron oxide black, medium chrome yellow and iron oxide blue. The composite solvent is two or more of ethanol, isopropanol, propylene glycol methyl ether and diacetone alcohol. The surface modifier is one or more of hydroxyl silicone oil, monoalkoxy titanate, KH550, KH560 and KH 570.

(III) preparation of the coating

And (3) stirring and mixing the film forming material resin in the step (I) and the composite slurry in the step (II) for 1h by using a stirrer according to the mass ratio of 1/5-5 at room temperature, adding an auxiliary agent (a leveling agent, a wetting agent and an anti-settling agent), continuously stirring and stirring for 1-2 h, filtering and discharging, and thus completing the preparation of the high-hardness wear-resistant metal anticorrosive paint.

According to the preparation method of the high-hardness wear-resistant metal anticorrosive paint, composite siloxane is adopted to modify nano silica sol in an acidic environment to obtain organic silicon modified composite sol, and paint film forming material resin prepared from the modified composite sol is combined with composite slurry to realize inorganic impurity of the organic paint, so that the hardness of the paint can be effectively improved, and according to detection, the hardness of the paint prepared by adopting the technology disclosed by the patent can reach 5H-6H, and is far higher than that of the existing metal anticorrosive paint.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.