Amphiphilic silicon dioxide composite filler for improving protective performance of water-based coating and preparation method of amphiphilic silicon dioxide composite filler

Abstract

The invention discloses an amphiphilic silicon dioxide composite filler capable of improving the protective performance of a water-based coating and a preparation method of the amphiphilic silicon dioxide composite filler, and relates to a water-based coating composite filler and a preparation method thereof.The method comprises the steps that hexadecyl trimethyl ammonium bromide is dispersed in deionized water, ammonia water is added to adjust the pH value, and the mixture is mixed with an organic solvent; after the reaction is finished, washing a product with deionized water and ethanol; the functional filler prepared by the method has amphipathy, is easy to disperse in a water-based coating, can be used after being mixed with the water-based coating according to a certain proportion, and can be used after the water-based coating is constructed and dried. A barrier layer is constructed from the hydrophobic side to the outer side of a coating interface in a self-orientation manner, so that the overall protection performance of the coating is improved, and the defect of poor water resistance of a water-based coating is overcome. And the method has a relatively wide application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of coating composite filler and its preparation method, in particular to a kind of amphiphilic silicon dioxide composite filler and its preparation method for improving the protective performance of water-based coating. BACKGROUND

[0002] With the strengthening of environmental protection policy, the coating industry faces green transformation, and the market share of water-based coating, solvent-free coating and other environmentally friendly coatings gradually increases. Water-based coating has good performance and low volatile organic compound emission, and is low in price, high in safety, good in compatibility, in line with the green and environmentally friendly consumer concept, and has good research and development prospects. Water-based resin coating is a stable dispersion system formed by dispersing resin in the form of particles or droplets in the continuous phase dispersion medium of water, but due to the introduction of hydrophilic groups or the addition of surfactants in the preparation process, the water resistance is reduced, and microcracks and cavities may occur during the curing process of water-based coating. How to improve the water resistance and other properties of water-based coating has become a key research, and the current hot modification method is to add nano fillers, which can build the rough structure and low surface energy characteristics required by the coating, produce "labyrinth effect", and prolong the penetration path of corrosion medium, so as to solve the microcracks generated during the curing process of water-based coating and improve the protective performance of water-based coating. However, nano fillers are prone to agglomeration, and solving the dispersion of nano fillers is the key to preparing high-performance water-based coating. SUMMARY

[0003] The purpose of the present application is to provide an amphiphilic silicon dioxide composite filler and its preparation method for improving the protective performance of water-based coating. In the method, cetyltrimethylammonium bromide is dispersed in deionized water, ammonia water is added to adjust the pH, and then mixed with organic solvent. After the reaction is completed, the product is washed with deionized water and ethanol. The obtained hydrophilic and lipophilic amphiphilic silicon dioxide composite filler is dispersed in ethanol solution, which improves the stability of water-based coating and improves the protective performance such as water resistance and corrosion resistance of the coating.

[0004] The technical solution of the present application is: An amphiphilic silicon dioxide composite filler for improving the protective performance of water-based coating, the mass fraction of raw materials of the filler is: 20 parts of tetraethyl orthosilicate, 8 parts of 3-aminopropyl triethoxysilane, 4 parts of phenyl triethoxysilane, 5 parts of cetyltrimethylammonium bromide and 1-3 parts of benzotriazole.

[0005] A preparation method of an amphiphilic nano silicon dioxide filler for improving the water resistance of water-based coating, the method comprising the following steps: Step 1, 5 parts of cetyltrimethylammonium bromide are weighed and dispersed in 1000 parts of deionized water, and then 25% ammonia water is added to adjust the pH to 10; Step 2, 20 parts of tetraethyl orthosilicate, 8 parts of 3-aminopropyl triethoxysilane, 4 parts of phenyl triethoxysilane and 400 parts of organic solvent are mixed; Step 3, the solution prepared in step 1 is mixed with the solution prepared in step 2, and shearing emulsification is carried out for 5 minutes, and the reaction system is fully stirred at 70 DEG C under water bath heating for 12 hours, and then the product is washed with deionized water and ethanol; Step 4, 1 part of the product obtained in step 3 is dispersed in 5 parts of ethanol solution, and 1 part of benzotriazole is dispersed in 25 parts of ethanol solution, and the temperature is kept at 25 DEG C and stirred for 12 hours, and then a hydrophilic and oleophilic amphiphilic silica composite filler is obtained, and the product is washed with deionized water; drying, grinding, and long-term storage.

[0006] The organic solvent of step 2 is toluene.

[0007] The amphiphilic silica composite filler for improving the protective performance of water-based coating and the preparation method thereof, the cetyltrimethylammonium bromide is adjusted to 1:20 with water, and the pH is adjusted to 10 with 25% ammonia water.

[0008] The beneficial effects of the present application are: 1. The functional filler prepared by the present application has two regions with different components and properties, and the partition is obvious, one side is hydrophilic and the other side is hydrophobic. The two amphiphilic characteristics of the functional filler solve the dispersion problem of the filler in the water-based coating. The flaky structure can improve the micro-cracks caused by resin curing, improve the compactness of the coating, load the corrosion inhibitor by using the mesoporous structure, improve the water resistance, and further improve the corrosion resistance of the water-based coating.

[0009] 2. The functional filler prepared by the present application has amphiphilicity, and can be easily dispersed in the water-based coating. The filler can be used by mixing with the water-based coating in a certain proportion. After the water-based coating is dried, the hydrophobic side is oriented to the outside of the coating interface to build a barrier layer, improve the overall protective performance of the coating, and improve the poor water resistance of the water-based coating. It has a broad application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 The process flow chart of the application. DETAILED DESCRIPTION

[0011] The technical solutions of the present application will be clearly and completely described below in combination with specific embodiments. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the protection scope of the present application.

[0012] An amphiphilic silica composite filler for improving the protection performance of a water-based coating, comprising the following raw materials in mass fraction: tetraethyl orthosilicate 20 parts, 3-aminopropyl triethoxysilane 8 parts, phenyl triethoxysilane 4 parts, hexadecyl trimethyl ammonium bromide 5 parts, benzotriazole 1-3 parts.

[0013] Further, the hexadecyl trimethyl ammonium bromide is adjusted at a ratio of 1:20 with water, and the pH is adjusted to 10 with 25% ammonia water.

[0014] A preparation method of an amphiphilic nano-silica filler for improving the water resistance of a water-based coating, comprising the following steps: Step 1: 5 parts of hexadecyl trimethyl ammonium bromide are weighed and dispersed in 1000 parts of deionized water, and then 25% ammonia water is added to adjust the pH to 10.

[0015] Step 2: 20 parts of tetraethyl orthosilicate, 8 parts of 3-aminopropyl triethoxysilane, 4 parts of phenyl triethoxysilane, and 400 parts of an organic solvent are mixed.

[0016] Step 3: The solution prepared in step 1 is mixed with the solution prepared in step 2, and shearing emulsification is performed for 5 minutes. The reaction system is fully stirred at 70°C in a water bath for 12 hours. After the reaction is completed, the product is washed with deionized water and ethanol.

[0017] Step 4: 1 part of the product obtained in step 3 is dispersed in 5 parts of an ethanol solution, and 1 part of benzotriazole is dispersed in 25 parts of an ethanol solution. Stirring is performed at 25°C for 12 hours. After the reaction is completed, an amphiphilic silica composite filler with one side hydrophilic and the other side oleophilic is obtained. The product is washed with deionized water, dried, ground, and stored for a long time. Further, the organic solvent in step 2 is toluene.

[0018] The present application provides a new functional filler for a water-based coating, which is synthesized from tetraethyl orthosilicate, 3-aminopropyl triethoxysilane, phenyl triethoxysilane, hexadecyl trimethyl ammonium bromide, and benzotriazole. Example 1

[0019] A preparation method of an amphiphilic silica composite filler for improving the protection performance of a water-based coating, comprising the following steps: Step 1, 5 parts of cetyltrimethylammonium bromide were dispersed in 1000 parts of deionized water, and then 25% ammonia water was added to adjust the pH to 10.

[0020] Step 2, 20 parts of tetraethyl orthosilicate, 8 parts of 3-aminopropyl triethoxysilane, and 4 parts of phenyl triethoxysilane were mixed with 400 parts of organic solvent.

[0021] Step 3, the solution prepared in step 1 was mixed with the solution prepared in step 2, and shearing emulsification was carried out for 5 min, and the reaction system was fully stirred at 70℃ in water bath for 12 h, and then the product was washed with deionized water and ethanol.

[0022] Step 4, 2 parts of the product obtained in step 3 were dispersed in 5 parts of ethanol solution, and 1 part of benzotriazole was dispersed in 25 parts of ethanol solution, and then constant temperature stirring was carried out at 25℃ for 12 h, and then a hydrophilic and oleophilic amphiphilic silica composite filler was obtained, and then the product was washed with deionized water.

[0023] Test performance. Example 2

[0024] A preparation method of an amphiphilic silica composite filler for improving the protection performance of water-based coating, comprising the following steps: Step 1, 5 parts of cetyltrimethylammonium bromide were dispersed in 1000 parts of deionized water, and then 25% ammonia water was added to adjust the pH to 10.

[0025] Step 2, 20 parts of tetraethyl orthosilicate, 8 parts of 3-aminopropyl triethoxysilane, and 4 parts of phenyl triethoxysilane were mixed with 400 parts of organic solvent.

[0026] Step 3, the solution prepared in step 1 was mixed with the solution prepared in step 2, and shearing emulsification was carried out for 5 min, and the reaction system was fully stirred at 70℃ in water bath for 12 h, and then the product was washed with deionized water and ethanol.

[0027] Step 4, 2 parts of the product obtained in step 3 were dispersed in 5 parts of ethanol solution, and 1 part of benzotriazole was dispersed in 25 parts of ethanol solution, and then constant temperature stirring was carried out at 25℃ for 12 h, and then a hydrophilic and oleophilic amphiphilic silica composite filler was obtained, and then the product was washed with deionized water.

[0028] Test performance. Example 3

[0029] A preparation method of an amphiphilic silica composite filler for improving the protection performance of water-based coating, comprising the following steps: Step 1, 5 parts of cetyltrimethylammonium bromide were dispersed in 1000 parts of deionized water, and then 25% ammonia water was added to adjust the pH to 10.

[0030] Step 2, 20 parts of tetraethyl orthosilicate, 8 parts of 3-aminopropyl triethoxysilane, and 4 parts of phenyl triethoxysilane were mixed with 400 parts of organic solvent.

[0031] Step 3, the solution prepared in step 1 was mixed with the solution prepared in step 2, and shearing emulsification was carried out for 5 min, and the reaction system was fully stirred at 70℃ in water bath for 12 h, and then the product was washed with deionized water and ethanol.

[0032] Step 4, 1 part of the product obtained in step 3 was dispersed in 5 parts of ethanol solution, and 2 parts of benzotriazole was dispersed in 25 parts of ethanol solution, and then constant temperature stirring was carried out at 25℃ for 12 h, and then a hydrophilic and oleophilic amphiphilic silica composite filler was obtained, and then the product was washed with deionized water.

[0033] Test performance. Example 4

[0034] A preparation method of an amphiphilic silica composite filler for improving the protective performance of a water-based coating, comprising the following steps: Step 1, 5 parts of cetyltrimethylammonium bromide were dispersed in 1000 parts of deionized water, and then 25% ammonia water was added to adjust the pH to 10.

[0035] Step 2, 20 parts of tetraethyl orthosilicate, 8 parts of 3-aminopropyl triethoxysilane, and 4 parts of phenyl triethoxysilane were mixed with 400 parts of organic solvent.

[0036] Step 3, the solution prepared in step 1 was mixed with the solution prepared in step 2, and shearing emulsification was carried out for 5 min, and the reaction system was fully stirred at 70℃ in water bath for 12 h, and then the product was washed with deionized water and ethanol.

[0037] Step 4, 3 parts of the product obtained in step 3 were dispersed in 5 parts of ethanol solution, and 1 part of benzotriazole was dispersed in 25 parts of ethanol solution, and then constant temperature stirring was carried out at 25℃ for 12 h, and then a hydrophilic and oleophilic amphiphilic silica composite filler was obtained, and then the product was washed with deionized water.

[0038] Test performance.

[0039] Examples 1-4 investigated the influence of benzotriazole loading fractions of 2:1, 1:1, 1:2, and 1:3 on the experiment.

[0040] The test method of the new functional filler for improving the performance of the water-based coating is as follows: The amphiphilic composite filler prepared in the examples and comparative examples of the present application was blended with 200 parts of waterborne epoxy resin and 120 parts of resin curing agent, 40 parts of deionized water, 6 parts of the filler, and then placed in a homogenizer and stirred at a speed of 6000 r / min for 10 minutes until uniform. The mixed coating was sprayed on a carbon steel sheet using a jet spray gun (pressure 0.3 MPa) at a thickness of about 60 microns. The sprayed sample was placed in a cool place and allowed to stand for 72 hours until completely cured to obtain a coating sample, and the performance was tested.

[0041] Table 1: Coating performance data.

[0042]

[0043] The coating prepared by the present application has a neutral salt spray resistance time of 960-2400 h; the water contact angle is up to 94°, and the electrochemical impedance value is between 3.6*10 7 -8.2*10 8 According to Examples 1-4, it can be seen that as the loading amount of benzotriazole increases, the water resistance (neutral salt spray resistance time, water contact angle, electrochemical impedance value) of the coating prepared by the amphiphilic functional filler also increases first and then decreases, and when the loading ratio is 1:1, the water resistance (acid salt spray resistance time, water contact angle, electrochemical impedance value) of the coating reaches the best.

Claims

1. An amphiphilic silica composite filler for improving the protective properties of waterborne coatings, characterized in that, The raw material of the filler mass fraction is: Ethyl orthosilicate 20 parts, 3-aminopropyl triethoxysilane 8 parts, phenyl triethoxysilane 4 parts, cetyl trimethyl ammonium bromide 5 parts, benzotriazole 1-3 parts.

2. A method for preparing an amphiphilic nanosilica filler for improving water resistance of waterborne coatings, characterized in that, The method comprises the following steps: Step 1, weigh 5 parts of cetyl trimethyl ammonium bromide and disperse in 1000 parts of deionized water, then add 25% ammonia water to adjust the pH to 10; Step 2, weigh 20 parts of ethyl orthosilicate, 8 parts of 3-aminopropyl triethoxysilane, 4 parts of phenyl triethoxysilane and 400 parts of organic solvent; Step 3, mix the solution prepared in step 1 with the solution prepared in step 2, shear emulsification for 5 min, the reaction system is fully stirred at 70℃ in water bath for 12 h, after the reaction is completed, the product is washed with deionized water and ethanol; Step 4, weigh 1 part of the product obtained in step 3 and disperse in 5 parts of ethanol solution, 1 part of benzotriazole is dispersed in 25 parts of ethanol solution, constant temperature stirring at 25℃ for 12 h, after the reaction is completed, a hydrophilic and oleophilic amphiphilic silica composite filler is obtained, the product is washed with deionized water, dried, ground and stored for a long time.

3. The method for preparing the amphiphilic silica composite filler for improving the protective performance of waterborne coatings according to claim 2, characterized in that, The organic solvent of step 2 is toluene.

4. The amphiphilic silica composite filler for improving the protective performance of waterborne coatings according to claim 1 or 2, and a preparation method thereof, characterized in that, The cetyl trimethyl ammonium bromide is mixed with water in a ratio of 1:20, and the pH is adjusted to 10 with 25% ammonia water.

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