CN113717557A - Self-layering inorganic hydrophobic coating material and preparation method thereof - Google Patents

Abstract

The invention provides a self-layering inorganic hydrophobic coating material and a preparation method thereof, wherein the inorganic hydrophobic coating material is prepared by A, B two groups of components, wherein the component A comprises water, an emulsifier, a silane coupling agent and a pH regulator, and the component B comprises water, titanium dioxide, calcium carbonate, kaolin, water glass, the component A and an auxiliary agent. The material composition and the preparation method of the invention realize the improvement of the hydrophobic property and the initial water resistance of the inorganic coating under the condition of lower content of the hydrophobic agent.

Description

Self-layering inorganic hydrophobic coating material and preparation method thereof

The technical field is as follows:

the invention relates to the field of architectural decoration, in particular to a self-layering inorganic hydrophobic coating material.

Background art:

with the increasing attention of human beings on environment and health, the water-based paint has been developed rapidly in recent years due to the advantages of small environmental pollution, low cost, no toxicity, no odor, no combustion and the like. The water-based inorganic coating is prepared by taking water glass (alkali metal silicate) or silica sol as a main binder and adding a proper amount of synthetic resin emulsion, pigment, filler and auxiliary agent, has the advantages of environmental protection, fire resistance, no toxicity, no harm and the like, and is more and more widely applied along with the development of the technology.

Inorganic coatings using alkali metal silicates as binders have a problem of poor initial water resistance due to a slow curing and crosslinking rate during use. In order to improve the initial water resistance, a large amount of hydrophobic auxiliary agent needs to be added for treatment, and the hydrophobic auxiliary agent is difficult to uniformly disperse, so that the quality of the inorganic coating is reduced.

The patent CN104530891A provides a room temperature crosslinking self-layering concrete protective coating and a preparation method thereof, the room temperature crosslinking self-layering concrete protective coating utilizes the incompatibility of siloxane modified fluorine-containing polyacrylic resin and polyacrylate to realize self-layering in the film forming process, and the hydrophobic and protective properties of the coating are improved; patent CN105462479A provides an environment-friendly weather-resistant self-layering single-component waterproof coating, which is prepared by incompatibility of aqueous polyurethane emulsion and aqueous polyurethane modified fluorocarbon resin emulsion; patent CN101724326A provides a water-based silicone-acrylic self-layered coating. The high-performance polymer emulsion with the self-layering effect is obtained by matching the water-based organic silicon resin emulsion, the organic silicon modified acrylic resin emulsion and the acrylic resin emulsion.

At present, self-layering coating (CN103525284A, CN102604003A, US8691342, US8229170) at home and abroad is mainly prepared by compounding silicon-containing or fluorine-containing resin with epoxy resin, acrylic resin and the like, and the self-layering effect is achieved by utilizing the difference of surface energy among the resins, so that the required hydrophobic and protective properties are realized. These methods have the disadvantage that phase separation occurs during storage and that the phase separation speed is slow during coating.

In order to solve the problem of poor initial water resistance of the existing inorganic coating, the invention provides a self-layered inorganic hydrophobic coating material and a preparation method thereof, which realize the improvement of the hydrophobic property and the initial water resistance of the inorganic coating under the condition of lower content of a hydrophobic agent.

Disclosure of Invention

From the above, the existing inorganic coating has poor initial water resistance, a large amount of hydrophobic auxiliary agent needs to be added for treatment, and the hydrophobic auxiliary agent is difficult to disperse uniformly, so that the quality of the inorganic coating is reduced; the existing self-layering coating is mainly compounded by silicon-containing or fluorine-containing resin, epoxy resin, acrylic resin and the like, and phase separation is realized by utilizing the difference of surface energy among the resins, so that the self-layering effect is achieved. These methods have the disadvantages that phase separation tends to occur during storage and that the phase separation speed is slow during coating.

Aiming at the problem of poor initial water resistance of the existing inorganic coating, the invention provides a self-layered inorganic hydrophobic coating material and a preparation method thereof.

The silane coupling agent containing long carbon chains has higher hydrophobic property, and has higher dispersity and compatibility in inorganic silicate resin after emulsification. In the product coating process, along with the volatilization of water, the electrolyte concentration in the system is increased, the emulsification system is damaged, the self-layering phenomenon is generated, and the silane coupling agent is separated from the water phase due to the lower surface energy, migrates to the surface and is enriched on the surface of the coating, so that the inorganic coating with higher hydrophobic performance is obtained.

The invention provides a self-layering inorganic hydrophobic coating material which comprises the following components in percentage by mass:

the mass percentage of the component B

The invention also provides a preparation method of the self-layering inorganic hydrophobic coating material, which comprises the following specific operation steps:

preparation of component A: adding a surfactant into the measured water, stirring and dissolving, adjusting the pH value of the system to 8-9, then slowly adding organosiloxane, and stirring for 10min to obtain a white emulsion, thereby obtaining the component A.

Preparation of the component B: adding 50% of water, cellulose ether, a dispersing agent, a wetting agent, a pH value regulator and 50% of a defoaming agent into a dispersion cylinder, uniformly stirring at the state of 300-400rpm, then adding titanium dioxide, kaolin and calcium carbonate, dispersing at the speed of 1500rpm of 1000-100-300 rpm until the fineness is less than or equal to 50 mu m, then adding the rest of water, acrylic emulsion and component A, stirring for 5min until the mixture is uniform, adding water glass, a stabilizing agent and the rest of the defoaming agent, dispersing for 10min until the system is free of bubbles, and finally adding a thickening agent to adjust to a proper viscosity.

The emulsifier of the invention is preferably a nonionic emulsifier, including but not limited to one or a combination of two or more of fatty alcohol polyoxyethylene ether, sorbitan fatty acid ester, castor oil/hydrogenated castor oil and ethylene oxide condensate, polyvinyl alcohol and the like.

The silane coupling agent is a long carbon chain silane coupling agent, and comprises but is not limited to one or the combination of two or more of phenyl trimethoxy silane, octyl trimethoxy silane, dodecyl trimethoxy silane, hexadecyl trimethoxy silane, octadecyl trimethoxy silane or silazane compound.

The pH regulator is organic amine.

The calcium carbonate is heavy calcium carbonate powder.

The titanium dioxide is rutile titanium dioxide.

The kaolin of the invention is calcined kaolin.

The water glass in the invention is potassium water glass and sodium water glass, preferably potassium water glass.

The other auxiliary agents are a polymer dispersant, an organic silicon defoamer, cellulose ether, a wetting agent, a stabilizer and an alkali swelling thickener.

Detailed Description

Example 1

(1) Weighing 50g of water, adding 1.5g of emulsifier AEO-9 under stirring, fully mixing and dissolving, adjusting the pH of a system to 8-9 by using AMP-95, and slowly adding 50g of dodecyl trimethoxy silane under stirring to obtain a component A;

(2) adding 15g of water, 0.4g of cellulose ether HBR250, 0.5g of dispersing agent, 0.2g of wetting agent, 0.05g of AMP-95 and 0.15g of defoaming agent into a dispersion cylinder, stirring uniformly under the state of 300-400rpm, adding 20g of titanium dioxide, 20g of kaolin and 10g of calcium carbonate, dispersing at 1500rpm until the fineness is less than or equal to 50 mu m, adjusting the rotating speed to 100-300rpm, adding the rest water, 7g of acrylic emulsion and 0.6g of the component A obtained in the step (1), stirring for 5min until the mixture is uniform, adding 25g of potassium water glass, 0.8g of stabilizing agent and 0.15g of defoaming agent, dispersing for 10min until the system is free of bubbles, and finally adding a thickening agent TT935 to adjust to the proper viscosity.

Example 2

(1) Weighing 60g of water, adding 1.0g of emulsifier AEO-9 and 0.5g of emulsifier AEO-3 under stirring, fully mixing and dissolving, adjusting the pH value of a system to 8-9 by using AMP-95, and slowly adding 40g of hexadecyl trimethoxy silane under stirring to obtain a component A;

(2) adding 15g of water, 0.4g of cellulose ether HBR250, 0.5g of dispersing agent, 0.2g of wetting agent, 0.05g of AMP-95 and 0.15g of defoaming agent into a dispersion cylinder, stirring uniformly under the state of 300-400rpm, adding 20g of titanium dioxide, 15g of kaolin and 15g of calcium carbonate, dispersing at 1500rpm until the fineness is less than or equal to 50 mu m, adjusting the rotating speed to 100-300rpm, adding the rest water, 7g of acrylic emulsion and 0.4g of the component A obtained in the step (1), stirring for 5min until the mixture is uniform, adding 25g of potassium water glass, 0.8g of stabilizing agent and 0.15g of defoaming agent, dispersing for 10min until the system is free of bubbles, and finally adding a thickening agent TT935 to adjust to the proper viscosity.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (5)

1. The self-layered inorganic hydrophobic coating material is characterized by comprising the following components in percentage by mass:

2. the self-layering inorganic hydrophobic coating material of claim 1, wherein the emulsifier is a nonionic emulsifier comprising one or a combination of two or more of fatty alcohol polyoxyethylene ether, sorbitan fatty acid ester, castor oil/hydrogenated castor oil and ethylene oxide condensate, polyvinyl alcohol, and the like.

3. The self-layered inorganic hydrophobic coating material of claim 1, wherein the silane coupling agent is a long carbon chain silane coupling agent comprising one or a combination of two or more of phenyltrimethoxysilane, octyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, octadecyltrimethoxysilane, or silazane compounds.

4. The self-layering inorganic hydrophobic coating material of claim 1, wherein the pH adjuster is an organic amine; the calcium carbonate is coarse whiting powder; the titanium dioxide is rutile type titanium dioxide; the kaolin is calcined kaolin; the water glass is potassium water glass and/or sodium water glass.

5. A method for preparing the self-stratifying inorganic hydrophobic coating material according to any of claims 1 to 4, characterized in that it comprises the following steps:

preparation of component A: adding a surfactant into the measured water, stirring and dissolving, adjusting the pH value of the system to 8-9, then slowly adding organosiloxane, and stirring for 10min to obtain a white emulsion, thereby obtaining a component A;

preparation of the component B: adding 50% of water, cellulose ether, a dispersing agent, a wetting agent, a pH value regulator and 50% of a defoaming agent into a dispersion cylinder, uniformly stirring at the state of 300-400rpm, then adding titanium dioxide, kaolin and calcium carbonate, dispersing at the speed of 1500rpm of 1000-100-300 rpm until the fineness is less than or equal to 50 mu m, then adding the rest of water, acrylic emulsion and component A, stirring for 5min until the mixture is uniform, adding water glass, a stabilizing agent and the rest of the defoaming agent, dispersing for 10min until the system is free of bubbles, and finally adding a thickening agent to adjust to a proper viscosity.