Preparation method of emulsion capsule type filler for improving protective performance of water-based paint

Abstract

The invention relates to a preparation method of an emulsion capsule type filler for improving the protective performance of a water-based paint, and relates to a preparation method of a water-based paint filler, the method comprises the following steps: weighing styrene, divinyl benzene, 25 # phase-change paraffin and azodiisobutyronitrile, uniformly mixing to obtain an oil phase, dissolving an emulsifier in water to obtain a water phase, adding the oil phase, heating, and stirring to obtain the emulsion capsule type filler for improving the protective performance of the water-based paint. Shearing and emulsifying by using a high-speed shearing machine; and centrifuging the emulsion obtained after the reaction is finished, sequentially washing the emulsion with a large amount of ethanol and deionized water for several times to remove paraffin so as to obtain amphiphilic polymer hemispheres, carrying out uniform ultrasonic treatment on water, adding an oily solvent, and emulsifying with a high-speed shearing machine so as to obtain the emulsion capsule type filler. A water-based coating prepared from the water-based protective paint has excellent protective performance, and not only can the stability of the water-based paint be improved, but also the protective performance of the paint can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to a coating filler preparation method, in particular to a emulsion capsule type filler preparation method for improving the protective performance of water-based paint. BACKGROUND

[0002] With the sustained and vigorous development of the construction industry, the market capacity shows a significant upward trend, and the demand for environmentally friendly coatings is particularly strong. As a representative of environmentally friendly coating materials, water-based coating products dominate the green coating market, but there are still technical bottlenecks in actual application: due to the introduction of surface active substances and hydrophilic functional groups in the water-based process, the coating film is prone to wetting effect after curing, which in turn causes the adhesion of the coating to decrease and peel off. This not only restricts the durability of the product, but also affects its decorative effect. Under the dual driving of increasingly stringent environmental regulations and consumer demand for quality, the development of environmentally friendly water-based coating functional fillers with excellent water resistance has become a technical problem that the industry needs to overcome.

[0003] The current research focus is on using functional fillers to construct coating matrix or interface microstructure system to achieve performance synergy between materials. It is worth noting that the lamellar filler can significantly enhance the barrier property of the coating medium and become the preferred solution to improve the protective performance of water-based paint. However, such materials are prone to interlayer agglomeration in water-based systems, which leads to insufficient dispersion uniformity, which not only weakens the dense structure of the coating, but also has a restrictive effect on the overall performance of the coating system. Therefore, it is necessary to develop a filler that can disperse well in water and improve the protective performance of water-based paint. SUMMARY

[0004] The purpose of the present application is to provide a emulsion capsule type filler preparation method for improving the protective performance of water-based paint, which uses self-assembled sol-gel method to induce phase separation to prepare amphiphilic silica filler, and load benzotriazole to prepare amphiphilic silica composite filler. By introducing amphiphilic silica filler into water-based epoxy coating system, the penetration path of corrosive medium is changed; and based on its unique amphiphilic property, the agglomeration problem of the filler in the resin matrix is improved, and the prepared water-based coating has excellent protective performance, which not only improves the stability of water-based paint, but also improves the protective performance of the paint.

[0005] The technical solution of the present application is as follows: A emulsion capsule type filler preparation method for improving the protective performance of water-based paint, the preparation steps of the method are: Step 1, weigh styrene, divinylbenzene, 25# phase change paraffin and azobisisobutyronitrile and mix evenly as oil phase, dissolve emulsifier in water as water phase; Step 2, the water phase in step 1 is added to the oil phase, and the temperature is raised, and shearing emulsification is carried out by using a high-speed shearing machine; Step 3, the emulsion in step 2 is weighed, and the water bath is heated under sufficient stirring, and the acrylamide solution is added 0.25h after the reaction starts, and the emulsion obtained after the reaction is finished is centrifuged, and the paraffin is removed by washing with a large amount of ethanol and deionized water for several times, so that the amphiphilic polymer hemisphere can be obtained, and the sample is dried and ground for long-term preservation of the sample. Step 4, after the sample in step 3 is uniformly ultrasonically mixed with water, an oily solvent is added, and emulsification is carried out by using a high-speed shearing machine, so that the emulsion capsule type filler can be obtained.

[0006] The emulsion capsule type filler for improving the protective performance of water-based paint is prepared by the method, and the filler is prepared from the following raw materials in mass fraction: Styrene 1-5 parts, divinylbenzene 1-4 parts, initiator 1-4 parts, emulsifier 1-4 parts, 25# phase change paraffin 5-10 parts, acrylamide 1-3 parts, and oily solvent 2-10 parts.

[0007] The emulsion capsule type filler for improving the protective performance of water-based paint is prepared by the method, and the emulsifier is sodium dodecyl sulfate.

[0008] The emulsion capsule type filler for improving the protective performance of water-based paint is prepared by the method, and the initiator is azobisisobutyronitrile.

[0009] The emulsion capsule type filler for improving the protective performance of water-based paint is prepared by the method, and the oily solvent is one of n-octyl triethoxysilane and tridecafluorooctyl triethoxysilane.

[0010] The emulsion capsule type filler for improving the protective performance of water-based paint is prepared by the method, and the acrylamide solution is mixed with water in a mass ratio of 1:10.

[0011] The emulsion capsule type filler for improving the protective performance of water-based paint is prepared by the method, and in step 1, the water is 25-100 mass parts.

[0012] The emulsion capsule type filler for improving the protective performance of water-based paint is prepared by the method, and in step 2, the temperature is raised to 70-75 DEG C.

[0013] The emulsion capsule type filler for improving the protective performance of water-based paint is prepared by the method, and in step 3, the heating temperature is 70-75 DEG C, and the reaction time is 8h.

[0014] The emulsion capsule type filler for improving the protective performance of water-based paint is prepared by the method, and in step 4, the sample is 1 mass part, and the water is 1-10 mass parts.

[0015] The emulsion capsule type filler for improving the protective performance of water-based paint is prepared by the method, and in step 4, the sample is 1 mass part, and the water is 1-10 mass parts. 1. The two-component amphiphilic polymer hemispheres prepared by this invention, due to their hydrophilic-lipophilic structure on one side and oleophilic-lipophilic structure on the other, act as solid emulsifiers to emulsify water and oily film-forming solvents. Furthermore, by controlling the ratio of oily solvent to water, the particles can precisely control the emulsion interface, forming an oil-in-water emulsion capsule-type filler. This solves the problem of fillers being difficult to disperse in water. When the filler emulsion is mixed with water-based coatings for application, the coagulation process causes the emulsion to break down, releasing the oily solvent, which polymerizes at the coating interface to form a barrier layer. This substantially improves the hydrophobicity of the water-based coating, making it less susceptible to wetting by water and greatly enhancing the coating's water resistance and corrosion resistance.

[0016] 2. The filler prepared by this invention is an oil-in-water system, which is easily dispersed in water-based coatings. It can be used simply by mixing it with the water-based coating in a specific ratio. After the water-based coating is applied and dried, the filler, through its self-orienting arrangement, releases nanofillers after emulsion demulsification and spontaneously forms a barrier layer at the coating interface with the oil-based film-forming solvent. The hydrophilic ends, facing inwards, consume the water-based segments in the water-based epoxy resin, compensating for the poor water resistance of water-based coatings and synergistically improving the overall protective performance of the coating. It has broad application prospects. Detailed Implementation

[0017] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] A method for preparing an emulsion capsule-type filler to improve the protective performance of water-based coatings includes the following steps: Step 1: Weigh out styrene, divinylbenzene, 25# phase change paraffin and azobisisobutyronitrile and mix them evenly as the oil phase. Dissolve the emulsifier in 25-100 parts of water as the aqueous phase.

[0019] Step 2: Add the aqueous phase from Step 1 to the oil phase and heat it to 70℃-75℃. Use a high-speed shearing machine to perform shearing emulsification.

[0020] Step 3: Weigh the emulsion from Step 2, stir thoroughly, and heat in a water bath to 70℃-75℃. 0.25h after the reaction begins, add an acrylamide solution prepared by mixing acrylamide solution and water in a mass ratio of 1:10. After the reaction is complete, centrifuge the emulsion obtained and wash it several times with large amounts of ethanol and deionized water to remove paraffin. The amphiphilic polymer hemispheres can then be obtained. Dry and grind the sample for long-term preservation.

[0021] Step 4, take 1 part of the sample in step 3 and 1-10 parts of water, ultrasonic homogenization, then add oil solvent, shear emulsification with high-speed shear machine, and then the emulsion capsule type filler can be obtained.

[0022] An emulsion capsule type filler for improving the protective performance of water-based paint, comprising the following raw materials in mass fraction: Styrene 1-5 parts, divinylbenzene 1-4 parts, initiator 1-4 parts, emulsifier 1-4 parts, 25# phase change paraffin 5-10 parts, acrylamide 1-3 parts, and oil solvent 1-10 parts.

[0023] Further, the emulsifier is sodium dodecyl sulfate.

[0024] Further, the initiator is azobisisobutyronitrile.

[0025] Further, the oil solvent is one of n-octyl triethoxysilane and tridecafluorooctyl triethoxysilane.

[0026] The present application provides a novel emulsion capsule type filler for water-based paint, which is synthesized from styrene, divinylbenzene, initiator, emulsifier, 25# paraffin, acrylamide, and oil solvent. Example 1

[0027] A preparation method of an emulsion capsule type filler for improving the protective performance of water-based paint, comprising the following steps: Step 1, 1 part of styrene, 1 part of divinylbenzene, 5 parts of 25# phase change paraffin, and 1 part of azobisisobutyronitrile are ultrasonically mixed to obtain an oil phase, and 2 parts of sodium dodecyl sulfate are dissolved in 50 parts of water to obtain an aqueous phase.

[0028] Step 2, the aqueous phase in step 1 is added to the oil phase and heated to 70-75 DEG C, and then sheared and emulsified with a high-speed shear machine for 5 minutes.

[0029] Step 3, take 1 part of the sample in step 2 and 8 parts of water, ultrasonic homogenization, then add 4 parts of n-octyl triethoxysilane, shear emulsification with high-speed shear machine for 1 min, and then the emulsion capsule type filler can be obtained.

[0030] Step 4, take 1 part of the sample in step 3 and 1-10 parts of water, ultrasonic homogenization, then add oil solvent, shear emulsification with high-speed shear machine, and then the emulsion capsule type filler can be obtained.

[0031] Fill in the water-based paint to test the performance. Example 2

[0032] A method for preparing an emulsion capsule type filler for improving the protective performance of water-based paint, comprising the following steps: Step 1: 1 part of styrene, 1 part of divinylbenzene, 5 parts of 25# phase change paraffin and 1 part of azobisisobutyronitrile are uniformly mixed by ultrasonic as the oil phase, and 2 parts of sodium dodecyl sulfate is dissolved in 50 parts of water as the water phase.

[0033] Step 2: The water phase in step 1 is added to the oil phase and heated to 70-75°C, and sheared and emulsified with a high-speed shearing machine for 5 minutes.

[0034] Step 3: Weigh the emulsion in step 2, fully stir and heat to 70-75°C in a water bath for 8 hours, add 2 parts of acrylamide solution with 20 parts of water in a mass ratio of 1:10 at 0.25 hours after the reaction starts, centrifuge the emulsion obtained after the reaction, and wash with a large amount of ethanol and deionized water several times to remove the paraffin, and the amphiphilic polymer hemispheres are obtained.

[0035] Step 4: Weigh 1 part of the sample in step 3 and 6 parts of water, ultrasonically mix them uniformly, then add 6 parts of n-octyl triethoxysilane, and shear and emulsify with a high-speed shearing machine for 1 minute to obtain the emulsion capsule type filler.

[0036] Fill in the water-based paint to test the performance. Example 3

[0037] A method for preparing an emulsion capsule type filler for improving the protective performance of water-based paint, comprising the following steps: Step 1: 1 part of styrene, 1 part of divinylbenzene, 5 parts of 25# phase change paraffin and 1 part of azobisisobutyronitrile are uniformly mixed by ultrasonic as the oil phase, and 2 parts of sodium dodecyl sulfate is dissolved in 50 parts of water as the water phase.

[0038] Step 2: The water phase in step 1 is added to the oil phase and heated to 70-75°C, and sheared and emulsified with a high-speed shearing machine for 5 minutes.

[0039] Step 3: Weigh the emulsion in step 2, fully stir and heat to 70-75°C in a water bath for 8 hours, add 2 parts of acrylamide solution with 20 parts of water in a mass ratio of 1:10 at 0.25 hours after the reaction starts, centrifuge the emulsion obtained after the reaction, and wash with a large amount of ethanol and deionized water several times to remove the paraffin, and the amphiphilic polymer hemispheres are obtained.

[0040] Step 4: Weigh 1 part of the sample in step 3 and 6 parts of water, ultrasonically mix them uniformly, then add 6 parts of n-octyl triethoxysilane, and shear and emulsify with a high-speed shearing machine for 1 minute to obtain the emulsion capsule type filler.

[0041] Fill in the water-based paint to test the performance. Example 4

[0042] A method for preparing an emulsion capsule type filler for improving the protective performance of water-based paint, comprising the following steps: Step 1, 1 part of styrene, 1 part of divinylbenzene, 5 parts of 25# phase change paraffin and 1 part of azobisisobutyronitrile are uniformly mixed by ultrasonic as the oil phase, and 2 parts of sodium dodecyl sulfate is dissolved in 50 parts of water as the water phase.

[0043] Step 2, add the water phase in step 1 to the oil phase and heat to 70-75°C, and shear emulsify with a high-speed shear machine for 5 minutes.

[0044] Step 3, weigh the emulsion in step 2, fully stir and heat to 70-75°C in a water bath for 8 hours, add 2 parts of acrylamide solution with 20 parts of water in a mass ratio of 1:10 at 0.25 hours after the start of the reaction, centrifuge the emulsion obtained after the reaction, and wash with a large amount of ethanol and deionized water several times to remove the paraffin, and the amphiphilic polymer hemispheres are obtained.

[0045] Step 4, weigh 1 part of the sample in step 3 and 8 parts of water, ultrasonically mix them uniformly, add 4 parts of tridecafluorooctyltriethoxysilane, and shear emulsify with a high-speed shear machine for 1 minute to obtain the emulsion capsule type filler.

[0046] Fill into water-based paint to test performance. Example 5

[0047] A method for preparing an emulsion capsule type filler for improving the protective performance of water-based paint, comprising the following steps: Step 1, 1 part of styrene, 1 part of divinylbenzene, 5 parts of 25# phase change paraffin and 1 part of azobisisobutyronitrile are uniformly mixed by ultrasonic as the oil phase, and 2 parts of sodium dodecyl sulfate is dissolved in 50 parts of water as the water phase.

[0048] Step 2, add the water phase in step 1 to the oil phase and heat to 70-75°C, and shear emulsify with a high-speed shear machine for 5 minutes.

[0049] Step 3, weigh the emulsion in step 2, fully stir and heat to 70-75°C in a water bath for 8 hours, add 2 parts of acrylamide solution with 20 parts of water in a mass ratio of 1:10 at 0.25 hours after the start of the reaction, centrifuge the emulsion obtained after the reaction, and wash with a large amount of ethanol and deionized water several times to remove the paraffin, and the amphiphilic polymer hemispheres are obtained.

[0050] Step 4, weigh 1 part of the sample in step 3 and 8 parts of water, ultrasonically mix them uniformly, add 4 parts of tridecafluorooctyltriethoxysilane, and shear emulsify with a high-speed shear machine for 1 minute to obtain the emulsion capsule type filler.

[0051] Fill in the water-based paint to test performance. Example 6

[0052] A method for preparing an emulsion capsule type filler for improving the protective performance of water-based paint, comprising the following steps: Step 1, 1 part of styrene, 1 part of divinylbenzene, 5 parts of 25# phase change paraffin and 1 part of azobisisobutyronitrile are uniformly mixed by ultrasonic as the oil phase, and 2 parts of sodium dodecyl sulfate is dissolved in 50 parts of water as the water phase.

[0053] Step 2, add the water phase in step 1 to the oil phase and heat to 70-75°C, and shear emulsify with a high-speed shear machine for 5 minutes.

[0054] Step 3, weigh the emulsion in step 2, fully stir and heat to 70-75°C in a water bath for 8 hours, add 2 parts of acrylamide solution with 20 parts of water with a mass ratio of 1:10 at 0.25 hours after the start of the reaction, centrifuge the emulsion obtained after the reaction, and wash with a large amount of ethanol and deionized water several times to remove the paraffin, and the amphiphilic polymer hemispheres are obtained.

[0055] Step 4, after ultrasonic mixing of 1 part of the sample in step 3 and 4 parts of water, 8 parts of tridecafluorooctyltriethoxysilane is added, and the high-speed shear machine is sheared and emulsified for 1 minute to obtain the emulsion capsule type filler.

[0056] Fill in the water-based paint to test performance. Comparative Example 1

[0057] A method for preparing an emulsion capsule type filler for improving the protective performance of water-based paint, comprising the following steps: Step 1, 1 part of styrene, 1 part of divinylbenzene, 5 parts of 25# phase change paraffin and 1 part of azobisisobutyronitrile are uniformly mixed by ultrasonic as the oil phase, and 2 parts of sodium dodecyl sulfate is dissolved in 50 parts of water as the water phase.

[0058] Step 2, add the water phase in step 1 to the oil phase and heat to 70-75°C, and shear emulsify with a high-speed shear machine for 5 minutes.

[0059] Step 3, weigh the emulsion in step 2, fully stir and heat to 70-75°C in a water bath for 8 hours, add 2 parts of acrylamide solution with 20 parts of water with a mass ratio of 1:10 at 0.25 hours after the start of the reaction, centrifuge the emulsion obtained after the reaction, and wash with a large amount of ethanol and deionized water several times to remove the paraffin, and the amphiphilic polymer hemispheres are obtained.

[0060] Step 4, take 1 part of the sample in step 3 and 9 parts of water, ultrasonic mixing, then add 3 parts of n-octyl triethoxysilane, shear emulsification with high speed shear machine for 1 min, to obtain emulsion capsule type filler.

[0061] Fill in the water-based paint to test performance. Comparative Example 2

[0062] A method for preparing an emulsion capsule type filler for improving the protective performance of water-based paint, comprising the following steps: Step 1, 1 part of styrene, 1 part of divinylbenzene, 5 parts of 25# phase change paraffin and 1 part of azobisisobutyronitrile are ultrasonically mixed to obtain an oil phase, and 2 parts of sodium dodecyl sulfate is dissolved in 50 parts of water to obtain an aqueous phase.

[0063] Step 2, add the aqueous phase in step 1 to the oil phase and heat to 70-75℃, shear emulsification with high speed shear machine for 5 min.

[0064] Step 3, take the emulsion in step 2, fully stir and heat to 70-75℃ in water bath for 8h, add 2 parts of acrylamide solution and 20 parts of water with a mass ratio of 1:10 to adjust the acrylamide solution at 0.25h after the reaction starts, centrifuge the emulsion obtained after the reaction, and wash with a large amount of ethanol and deionized water several times to remove the paraffin, to obtain amphiphilic polymer hemispheres.

[0065] Step 4, take 1 part of the sample in step 3 and 9 parts of water, ultrasonic mixing, then add 3 parts of n-octyl triethoxysilane, shear emulsification with high speed shear machine for 1 min, to obtain emulsion capsule type filler.

[0066] Fill in the water-based paint to test performance. Comparative Example 3

[0067] Water-based epoxy resin coating without adding emulsion capsule type filler.

[0068] Test performance.

[0069] Examples 1-3 and Comparative Example 1 investigated the influence of the ratio of water and n-octyl triethoxysilane added in parts by 2:1, 1:1, 1:2, 9:3.

[0070] Examples 4-6 and Comparative Example 2 investigated the influence of the ratio of water and n-octyl triethoxysilane added in parts by 2:1, 1:1, 1:2, 9:3.

[0071] The method for testing the performance of emulsion capsule type filler for improving the performance of water-based paint is as follows: The emulsion capsule type filler prepared in the inventive examples and the comparative examples was blended with 1000 parts of waterborne epoxy resin and 600 parts of resin curing agent, and was placed into a homogenizer for stirring at a speed of 8000 r / min for 10 minutes until uniform; the mixed coating after stirring was sprayed on a carbon steel sheet using a 5 mm caliber spray gun, and the spraying thickness was controlled at about 70 microns; the sprayed sample was placed in a cool place, and was allowed to stand for 72 hours until completely cured to obtain a coating sample, and the performance was tested.

[0072] Table 1 Coating performance data

[0073] The waterborne coating prepared by the present application has a neutral salt spray resistance time of 2200-3600 h, an acid salt spray resistance time of 800-1800 h, a water contact angle of up to 148°, and an electrochemical impedance value of 0.8*10 10 -3.9*10 10 According to Examples 1-3 and Comparative Example 1, it can be seen that as the ratio of water to n-octyl triethoxysilane increases, the protective performance (acid salt spray resistance time, water contact angle, electrochemical impedance value) of the coating prepared using the emulsion capsule type filler gradually decreases. According to Examples 4-6 and Comparative Example 2, it can be seen that as the ratio of water to tridecafluorooctyl triethoxysilane increases, the protective performance (acid salt spray resistance time, water contact angle, electrochemical impedance value) of the coating prepared using the emulsion capsule type filler first increases and then decreases. According to Comparative Example 3 and Examples 1-6, it can be seen that the addition of the emulsion capsule type filler significantly improves the protective performance (acid salt spray resistance time, water contact angle, electrochemical impedance value) of the waterborne coating.

Claims

1. A method for preparing an emulsion capsule-type filler to improve the protective performance of waterborne coatings, characterized in that, The preparation steps of the method are as follows: Step 1: Weigh out styrene, divinylbenzene, 25# phase change paraffin and azobisisobutyronitrile and mix them evenly as the oil phase. Dissolve the emulsifier in water as the aqueous phase. Step 2: Add the aqueous phase from Step 1 to the oil phase and heat it up. Then, use a high-speed shear machine to perform shear emulsification. Step 3: Weigh the emulsion from Step 2, stir thoroughly, and heat in a water bath. Add acrylamide solution 0.25 h after the reaction begins. Centrifuge the emulsion obtained after the reaction is complete, and wash it several times with large amounts of ethanol and deionized water to remove paraffin. The amphiphilic polymer hemispheres can then be obtained. Dry and grind the sample for long-term preservation. Step 4: Weigh the sample from Step 3 and sonicate it with water. Then add an oily solvent and emulsify it using a high-speed shearing machine to obtain the emulsion capsule filler.

2. The method for preparing an emulsion capsule-type filler to improve the protective performance of waterborne coatings according to claim 1, characterized in that, The filler is made of the following raw materials in parts by weight: 1-5 parts styrene, 1-4 parts divinylbenzene, 1-4 parts initiator, 1-4 parts emulsifier, 5-10 parts 25# phase change paraffin, 1-3 parts acrylamide, and 2-10 parts oily solvent.

3. The method for preparing an emulsion capsule-type filler to improve the protective performance of waterborne coatings according to claim 1, characterized in that, The emulsifier is sodium dodecyl sulfate.

4. The method for preparing an emulsion capsule-type filler to improve the protective performance of waterborne coatings according to claim 1, characterized in that, The initiator is azobisisobutyronitrile.

5. The method for preparing an emulsion capsule-type filler to improve the protective performance of waterborne coatings according to claim 1, characterized in that, The oily solvent is one of n-octyltriethoxysilane and tridecafluorooctyltriethoxysilane.

6. The method for preparing an emulsion capsule-type filler to improve the protective performance of waterborne coatings according to claim 1, characterized in that, The acrylamide solution was mixed with water at a mass ratio of 1:

10.

7. The method for preparing an emulsion capsule-type filler to improve the protective performance of waterborne coatings according to claim 1, characterized in that, In step 1, the amount of water is 25-100 parts by weight.

8. The method for preparing an emulsion capsule-type filler to improve the protective performance of waterborne coatings according to claim 1, characterized in that, In step 2, the temperature is raised to 70℃-75℃.

9. The method for preparing an emulsion capsule-type filler to improve the protective performance of waterborne coatings according to claim 1, characterized in that, In step 3, the reaction is carried out at 70℃-75℃ for 8 hours.

10. The method for preparing an emulsion capsule-type filler to improve the protective performance of waterborne coatings according to claim 1, characterized in that, In step 4, the sample is 1 part by mass; the water is 1-10 parts by mass.

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