A self-crosslinking multicolor paint and a preparation method thereof

Abstract

The present application belongs to the technical field of multi-color water-based paint, and particularly relates to a self-crosslinking multi-color paint and a preparation method thereof. The self-crosslinking multi-color paint provided by the present application comprises a sand-containing color point base paint, a granulation liquid and a continuous phase, wherein the sand-containing color point base paint comprises a multi-color base paint emulsion containing an acetoacetyl group and a gamma-aminopropyl triethoxysilane modified pigment and filler, and the continuous phase comprises a continuous phase emulsion containing an acetoacetyl group. The self-crosslinking multi-color paint realizes room temperature self-crosslinking of multi-color color points and a continuous phase in the film forming process of the water-in-sand multi-color paint through a crosslinking reaction mechanism and the like, improves the crosslinking density and mechanical strength of the multi-color coating film, solves the problems of poor mechanical strength, poor water resistance, poor stain resistance and low coating film density of the traditional water-in-sand multi-color paint, and solves the problems of poor water resistance and poor durability of the multi-color water-in-sand coating film in the initial stage.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of multi-color water-based paint, and particularly relates to a self-crosslinking multi-color paint and a preparation method thereof. BACKGROUND

[0002] With the increasing awareness of environment and health, traditional organic solvent-based coatings are gradually replaced by new water-based coatings due to the disadvantages of serious pollution and high energy consumption. The water-based coatings prepared by using acrylic resin as basic raw material are paid more and more attention due to the obvious environmental protection superiority and many excellent use performances. Among them, the multi-color water-sand coating has good stone-imitating effect and is favored in the field of wall coating.

[0003] However, the water resistance and mechanical strength of the coating film formed by the existing multi-color water-sand coating have obvious defects. Especially after being damp or encountering water, the paint film becomes soft and white, the long-term durability is affected, and problems such as powdering and separation occur. SUMMARY

[0004] In view of the above technical problems, the application provides a self-crosslinking multi-color paint, a preparation method and application thereof. The self-crosslinking multi-color paint provided by the application can occur self-crosslinking reaction at room temperature, and the formed paint film has good water resistance, stain resistance and mechanical strength.

[0005] To achieve the above application purposes, the application adopts the following technical solutions:

[0006] The application provides a self-crosslinking multi-color paint in the first aspect, which comprises sand-containing color point base paint, granulation liquid and continuous phase; the mass ratio of the three is (54-66):(18-22):(18-22).

[0007] The sand-containing color point base paint comprises the following raw materials in mass fraction: multi-color base paint emulsion containing acetoacetyl group 9-12 parts; gamma-aminopropyl triethoxysilane modified pigment and filler 2.5-4 parts; hydroxyethyl cellulose 0.4-0.8 parts; film forming aid 0.4-0.7 parts; pH regulator 0.03-0.05 parts; dispersant 0.04-0.08 parts; defoaming agent 0.2-0.3 parts; protective colloid solution 2.5-4.5 parts; quartz sand 20-30 parts; and water 10-22 parts.

[0008] The granulation liquid comprises the following raw materials in mass fraction: protective colloid solution 9-12.5 parts, anti-settling agent 0.06-0.1 parts, and water 7-11 parts.

[0009] The continuous phase comprises the following raw materials in terms of mass fraction: continuous phase emulsion containing acetoacetoxy 12-15 parts, film forming aid 0.5-0.8 parts, pH regulator 0.05-0.1 parts, defoaming agent 0.05-0.1 parts, thickening agent 0.15-0.3 parts, and water 3-6.5 parts.

[0010] In the self-crosslinking multi-color paint, the acetoacetoxy-containing acrylic emulsion is used as the main film-forming material in the sand-containing color point base paint, and the typical structure of the acetoacetoxy is acetoacetoxy methyl acrylate (AAEM). Figure 1

[0011] The active hydrogen on the methylene of the acetoacetoxy and the acetyl carbonyl can form a crosslinking reaction with the amine (or hydrazine) in the gamma-aminopropyl triethoxysilane modified pigment and filler through dehydration, and the reaction mechanism is as shown in Figure 2

[0012] Based on the above mechanism, the acetoacetoxy-containing acrylic emulsion in the sand-containing color point base paint and the gamma-aminopropyl triethoxysilane modified pigment and filler will undergo a crosslinking reaction during film formation, and at the same time, the continuous phase emulsion containing acetoacetoxy in the continuous phase will undergo a crosslinking reaction with the gamma-aminopropyl triethoxysilane modified pigment and filler in the base paint, so that the color points of the base paint and the continuous phase form a chemical crosslinked network structure, which not only improves the compactness of the base color points, but also improves the overall compactness of the self-crosslinking multi-color paint film, thereby significantly enhancing the film strength of the self-crosslinking multi-color paint, and solving the connection strength between the multi-color color points and the continuous paint film, improving the water resistance, durability and stain resistance of the paint film. The detailed reaction process of the crosslinking reaction is as shown in Figure 3

[0013] At the same time, the card house structure formed by the protective glue hydration (as shown in Figure 4 ) ensures the stability of the color points, and the crosslinking reaction between the hydroxyethyl cellulose and the protective glue (as shown in Figure 5 ) can form sand-containing color particles as shown in Figure 6 .

[0014] Through the above mechanism, the self-crosslinking multi-color paint provided by the present application realizes the room temperature self-crosslinking of the multi-color color points and the continuous phase during the film formation of the water-in-sand multi-color paint, improves the crosslinking density and mechanical strength of the multi-color coating film, solves the problems of poor mechanical strength, poor water resistance, poor stain resistance and low compactness of the coating film of the traditional water-in-sand multi-color paint, and solves the problems of poor water resistance and poor durability of the multi-color water-in-sand coating film in the initial stage.

[0015] ​​​In combination with the first aspect, the sand-containing color point base paint further comprises at least one of the following raw materials in terms of mass fraction: antifreeze 0.3-0.6 parts, bactericide 0.15-0.3 parts.

[0016] In combination with the first aspect, the granulation liquid further comprises bactericide 0.1-0.15 parts in terms of mass fraction.

[0017] In combination with the first aspect, the continuous phase further comprises at least one of the following raw materials in terms of mass fraction: antifreeze 0.3-0.6 parts, bactericide 0.1-0.2 parts.

[0018] Preferably, the above-mentioned antifreeze can be selected from ethylene glycol or propylene glycol, and the bactericide can be selected from CMIT, BIT or MIT type or a compound of the three.

[0019] In combination with the first aspect, the mass ratio of the sand-containing color point base paint, the granulation liquid and the continuous phase is preferably 60:20:20.

[0020] In combination with the first aspect, the multi-color base paint emulsion containing acetoacetyl groups is a pure acrylic emulsion or a silicone-acrylic emulsion modified by acetoacetyl groups.

[0021] In combination with the first aspect, the continuous phase emulsion containing acetoacetyl groups is a pure acrylic emulsion or a silicone-acrylic emulsion modified by acetoacetyl groups.

[0022] In combination with the first aspect, the type of hydroxyethyl cellulose is 250HBR, 250HHBR or 10K.

[0023] In combination with the first aspect, the film-forming aid is alcohol ester twelve.

[0024] In combination with the first aspect, the dispersant is a carboxylic acid sodium salt dispersant such as SN-5040, or a carboxylic acid ammonium salt dispersant such as SN-5027.

[0025] In combination with the first aspect, the defoaming agent is an organic silicon or mineral oil type defoaming agent, preferably a mineral oil type general defoaming agent NXZ.

[0026] In combination with the first aspect, the protective glue solution is a 8%-10%wt aqueous solution of lithium magnesium silicate.

[0027] In combination with the first aspect, the anti-settling agent is xanthan gum.

[0028] In combination with the first aspect, the pH adjuster is sodium bicarbonate.

[0029] In combination with the first aspect, the thickening agent is an alkali-swellable acrylic thickening agent, preferably TT615, TT935 or a compound of the two.

[0030] Preferably, the acetoacetoxy-containing multi-color base paint emulsion comprises, by mass fraction: deionized water 95-110 parts, emulsifier 1.5-2.0 parts, sodium bicarbonate buffer 0.3-0.35 parts, monomer mixture 139-183 parts, and initiator 0.21-0.24 parts; wherein the monomer mixture comprises, by mass fraction: acetoacetoxy ethyl methacrylate (AAEM) 12-18 parts, methyl methacrylate (MMA) 28-35 parts, butyl acrylate (BA) 38-45 parts, emulsifier 1.5-2.0 parts, and water 65-80 parts.

[0031] Preferably, the acetoacetoxy-containing continuous phase emulsion comprises, by mass fraction: deionized water 110-120 parts, emulsifier 1.5-2.0 parts, sodium bicarbonate buffer 0.3-0.35 parts, monomer mixture 150-180.5 parts, and initiator 0.21-0.24 parts; wherein the monomer mixture comprises, by mass fraction: acetoacetoxy ethyl methacrylate 12-18 parts, methyl methacrylate 30-35 parts, acrylic acid (AA) 30-38 parts, emulsifier 1.5-2.0 parts, and water 75-85 parts.

[0032] Preferably, the emulsifier is octylphenol polyoxyethylene ether (OP-10) and sodium dodecyl sulfate (SDS) in a mass ratio of 3.4-5.2:1.

[0033] Preferably, the initiator is ammonium persulfate (APS).

[0034] Optionally, the preparation method of the acetoacetoxy-containing multi-color base paint emulsion and the continuous phase emulsion can adopt the following operations: 0.17-0.18 parts of initiator is dissolved in 16-24 parts of water, and the remaining initiator is dissolved in 8-12 parts of water; the remaining deionized water, emulsifier, sodium bicarbonate buffer, and 1.5-2.5 parts of monomer mixture are uniformly dispersed and stirred, then heated to 57-63°C with a water bath, 0.17-0.18 parts of initiator (dissolved in 20 parts of water) is added, and the temperature is continuously raised to 67-73°C, the pre-emulsified monomer mixture is slowly added, and the reaction is kept for 1-1.5 hours, then the remaining initiator (dissolved in 10 parts of water) is added, the temperature is raised to 77-83°C, and the temperature is kept for 2-2.5 hours, and then the temperature is lowered to room temperature.

[0035] In combination with the first aspect, the γ-aminopropyl triethoxysilane modified pigment and filler is at least one of γ-aminopropyl triethoxysilane modified titanium dioxide or calcined kaolin.

[0036] Preferably, the preparation method of the gamma-aminopropyl triethoxysilane modified pigment and filler is as follows: mixing titanium dioxide or calcined kaolin, gamma-aminopropyl triethoxysilane, deionized water and anhydrous ethanol, adjusting pH to 3-6 with glacial acetic acid and ammonia water, and then ultrasonic dispersing at 30-60℃ and 50-60Hz for at least 50min, and then washing, filtering and drying to obtain the product; the mass of the gamma-aminopropyl triethoxysilane is 2%-6% of the mass of the titanium dioxide or calcined kaolin. The main reaction principle is as shown in Figure 7 . .

[0037] During the hydrolysis modification process of the gamma-aminopropyl triethoxysilane, a certain proportion of silane will also undergo crosslinking reaction, and the reaction mechanism is as shown in Figure 8 . .

[0038] Preferably, the pH is adjusted to 4-6. .

[0039] Preferably, the ultrasonic dispersing is carried out at 40-45℃. .

[0040] Preferably, the mass of the gamma-aminopropyl triethoxysilane is 3%-4.5% of the mass of the titanium dioxide or calcined kaolin. .

[0041] In the second aspect, the application further provides a preparation method of the self-crosslinking multi-color paint, which specifically comprises the following operations: adding the sand-containing color point base paint into the granulation liquid, granulating, and then adding into the continuous phase and uniformly mixing to obtain the self-crosslinking multi-color paint. .

[0042] The preparation method is simple and easy to implement, and can be used in actual production. BRIEF DESCRIPTION OF DRAWINGS .

[0043] . Figure 1 is a structural formula schematic diagram of acetoacetoxy methyl methacrylate (AAEM) and acetoacetoxy-containing acrylic emulsion; .

[0044] . Figure 2 is a reaction mechanism schematic diagram of the crosslinking reaction of the methylene and acetyl carbonyl on the acetoacetoxy and amine (or hydrazine) dehydration; .

[0045] . Figure 3 is a reaction mechanism schematic diagram of the crosslinking reaction of the acetoacetoxy-containing acrylic emulsion and the acetoacetoxy-containing continuous phase emulsion and the gamma-aminopropyl triethoxysilane modified pigment and filler during the film forming process; .

[0046] . Figure 4 is a process schematic diagram of the formation of a card house structure by the protection glue hydration; .

[0047] . Figure 5 is a process schematic diagram of the crosslinking reaction of the hydroxyethyl cellulose and the protection glue;

[0048] Figure 6 The structure diagram of the sand-containing color particle.

[0049] Figure 7 The reaction principle schematic diagram of the modification process of the gamma-aminopropyl triethoxysilane modified pigment filler;

[0050] Figure 8 The reaction mechanism schematic diagram of the cross-linking reaction of the gamma-aminopropyl triethoxysilane in the hydrolysis modification process;

[0051] Figure 9 The sedimentation performance of the gamma-aminopropyl triethoxysilane modified pigment filler prepared at different pH values in the test example 2 of the application;

[0052] Figure 10 The sedimentation performance of the gamma-aminopropyl triethoxysilane modified pigment filler prepared at different temperatures in the test example 2 of the application;

[0053] Figure 11 The sedimentation performance of the gamma-aminopropyl triethoxysilane modified pigment filler prepared at different ultrasonic dispersion times in the test example 2 of the application;

[0054] Figure 12 The sedimentation performance of the gamma-aminopropyl triethoxysilane modified pigment filler prepared at different silane coupling agent dosages in the test example 2 of the application. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with specific examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application.

[0056] The multi-color water-sand coating belongs to the relatively environment-friendly water-based coating, and is paid more and more attention in the wall coating field due to its good stone-imitating effect. However, the water resistance and mechanical strength of the coating film formed by the existing multi-color water-sand coating have obvious defects, especially after being damp or encountering water, the paint film becomes soft and whitish, the long-term durability is also affected, and problems such as powdering and separation occur. Therefore, it has great practical significance to develop a multi-color paint system with high mechanical strength and good water resistance for improving the performance of the paint film of the exterior wall.

[0057] In order to solve the above problems, the present application provides a self-crosslinking multi-color paint, which comprises a sand-containing color point base paint, a granulation liquid and a continuous phase; the mass ratio of the three is (54-66):(18-22):(18-22);

[0058] The sand-containing color dot base paint comprises the following raw materials in parts by mass: acetoacetyl group-containing multi-color base paint emulsion 9-12 parts; γ-aminopropyl triethoxysilane modified pigment and filler 2.5-4 parts; hydroxyethyl cellulose 0.4-0.8 parts; film forming aid 0.4-0.7 parts; pH regulator 0.03-0.05 parts; dispersant 0.04-0.08 parts; defoamer 0.2-0.3 parts; protective peptizing solution 2.5-4.5 parts; quartz sand 20-30 parts; and water 10-22 parts;

[0059] The granulation liquid comprises the following raw materials in parts by mass: protective peptizing solution 9-12.5 parts, anti-settling agent 0.06-0.1 parts, and water 7-11 parts;

[0060] The continuous phase comprises the following raw materials in parts by mass: acetoacetyl group-containing continuous phase emulsion 12-15 parts, film forming aid 0.5-0.8 parts, pH regulator 0.05-0.1 parts, defoamer 0.05-0.1 parts, thickening agent 0.15-0.3 parts, and water 3-6.5 parts.

[0061] As a preferred embodiment of the present application, the sand-containing color dot base paint further comprises at least one of the following raw materials in parts by mass: antifreeze 0.3-0.6 parts, and bactericide 0.15-0.3 parts; the granulation liquid further comprises bactericide 0.1-0.15 parts in parts by mass; and the continuous phase further comprises at least one of the following raw materials in parts by mass: antifreeze 0.3-0.6 parts, and bactericide 0.1-0.2 parts.

[0062] As a preferred embodiment of the present application, the mass ratio of the sand-containing color dot base paint, the granulation liquid, and the continuous phase is 60:20:20. Under the preferred ratio, the self-crosslinking multi-color paint obtained has higher mechanical strength and better water resistance.

[0063] As a preferred embodiment of the present application, the acetoacetyl group-containing multi-color base paint emulsion and the acetoacetyl group-containing continuous phase emulsion are both acetoacetyl group-modified pure acrylic emulsion or silicone-acrylic emulsion.

[0064] As a preferred embodiment of the present application, the hydroxyethyl cellulose is of type 250HBR, 250HHBR, or 10K; the film forming aid is alcohol ester twelve; the dispersant is carboxylic acid sodium salt dispersant, such as SN-5040, or carboxylic acid ammonium salt dispersant, such as SN-5027; the defoamer is silicone or mineral oil type defoamer, preferably mineral oil type general defoamer NXZ; the protective peptizing solution is 8%-10% lithium magnesium silicate aqueous solution; the anti-settling agent is xanthan gum; and the thickening agent is alkali swelling type acrylic thickening agent, preferably TT615, TT935, or a combination of the two. The above raw materials help to give the self-crosslinking multi-color paint better mechanical strength and water resistance.

[0065] As a preferred embodiment of the present application, the pH regulator is sodium bicarbonate. The sodium bicarbonate is a non-amine (ammonia) regulator, which can avoid reaction with the acetoacetoxy modified emulsion to cause demulsification; in addition, the sodium bicarbonate can also maintain the acid-base environment of the system, maintain the pH of the system at about 8, avoid the hydrolysis of acetoacetoxy, and at the same time maintain the stability of the coating system.

[0066] As a preferred embodiment of the present application, the multi-color base paint emulsion containing acetoacetoxy includes the following raw materials in parts by mass: deionized water 95-110 parts, emulsifier 1.5-2.0 parts, sodium bicarbonate buffer 0.3-0.35 parts, monomer mixture 139-183 parts, and initiator 0.21-0.24 parts; wherein the monomer mixture includes the following raw materials in parts by mass: acetoacetoxy ethyl methacrylate 12-18 parts, methyl methacrylate 28-35 parts, butyl acrylate 38-45 parts, emulsifier 1.5-2.0 parts, and water 65-80 parts. The continuous phase emulsion containing acetoacetoxy includes the following raw materials in parts by mass: deionized water 110-120 parts, emulsifier 1.5-2.0 parts, sodium bicarbonate buffer 0.3-0.35 parts, monomer mixture 150-180.5 parts, and initiator 0.21-0.24 parts; wherein the monomer mixture includes the following raw materials in parts by mass: acetoacetoxy ethyl methacrylate 12-18 parts, methyl methacrylate 30-35 parts, acrylic acid (AA) 30-38 parts, emulsifier 1.5-2.0 parts, and water 75-85 parts. The emulsifier preferably uses octylphenol polyoxyethylene ether and sodium dodecyl sulfate in a mass ratio of 3.4-5.2:1, and the initiator preferably uses ammonium persulfate.

[0067] The preparation method of the above-mentioned multi-color base paint emulsion and continuous phase emulsion containing acetoacetoxy can use the following operation: 0.17-0.18 parts of initiator is dissolved in 16-24 parts of water, and the remaining initiator is dissolved in 8-12 parts of water; the remaining deionized water, emulsifier, sodium bicarbonate buffer, and 1.5-2.5 parts of monomer mixture are uniformly dispersed and stirred, then heated to 57-63°C with a water bath, 0.17-0.18 parts of initiator (dissolved in 20 parts of water) is added, and the temperature is continuously raised to 67-73°C, the pre-emulsified monomer mixture is slowly added, and the reaction is maintained for 1-1.5 hours, then the remaining initiator (dissolved in 10 parts of water) is added, the temperature is raised to 77-83°C, and the temperature is maintained for 2-2.5 hours, and then the temperature is lowered to room temperature.

[0068] As a preferred embodiment of the present application, the gamma-aminopropyl triethoxysilane modified pigment and filler is at least one of gamma-aminopropyl triethoxysilane modified titanium dioxide or calcined kaolin. The modification method can use the following operation: mixing titanium dioxide or calcined kaolin, gamma-aminopropyl triethoxysilane, deionized water, anhydrous ethanol, adjusting the pH to 3-6 with glacial acetic acid and ammonia water, and then ultrasonic dispersion at 30-60℃ for 50-60Hz for at least 50min, washing, filtering, and drying to obtain the product; the mass of the gamma-aminopropyl triethoxysilane is 2%-6% of the mass of the titanium dioxide or calcined kaolin.

[0069] The present application also provides a preparation method of the self-crosslinking multi-color paint, which comprises the following steps: adding the sand-containing color point base paint into the granulation liquid, granulating, and then adding into the continuous phase and uniformly mixing to obtain the self-crosslinking multi-color paint.

[0070] The present application is further described in the following embodiments.

[0071] The raw materials used in the following embodiments are commercially available unless otherwise specified. Embodiments 1-5

[0072] Embodiments 1-5 of the present application respectively provide a self-crosslinking multi-color paint, and the raw materials, mass fractions and mass ratios are shown in Tables 1-4:

[0073] Table 1 Raw materials and mass fractions of the sand-containing color point base paint in embodiments 1-5

[0074]

[0075] Table 2 Raw materials and mass fractions of the granulation liquid in embodiments 1-5

[0076]

[0077] Table 3 Raw materials and mass fractions of the continuous phase in embodiments 1-5

[0078]

[0079] Table 4 Mass ratios of the sand-containing color point base paint, the granulation liquid and the continuous phase in embodiments 1-5

[0080]

[0081] In the above Examples 1-5, the multi-color base paint emulsion containing acetoacetoxy group was prepared by the following method: in a three-necked flask equipped with a stirrer and a condenser, 70 g of deionized water, 1.4 g of emulsifier (octylphenol polyoxyethylene ether OP-10), 0.35 g of sodium dodecyl sulfate SDS, 0.3 g of sodium bicarbonate buffer, and 2 g of a part of monomer mixture were added, and stirred and dispersed uniformly, then heated to 60°C using a water bath, 0.175 g of initiator ammonium persulfate APS (dissolved in 20 mL of water) was added, and the temperature was further increased to 70°C, then the remaining monomer mixture was added dropwise, 2 hours for dropwise addition, then the temperature was maintained for 1 hour, then 0.05 g of initiator ammonium sulfate APS (dissolved in 10 mL of water) was added, then the temperature was increased to 80°C for 2 hours of curing, the reaction was completed, the temperature was decreased to room temperature, and the product was discharged. The raw materials of the monomer mixture were 15 g of acetoacetoxy methyl acrylate AAEM, 31 g of methyl methacrylate MMA, 42 g of butyl acrylate BA, 1.4 g of octylphenol polyoxyethylene ether OP-10, 0.35 g of sodium dodecyl sulfate SDS, and 70 mL of water.

[0082] The continuous phase emulsion containing acetoacetoxy group was prepared by the following method: in a three-necked flask equipped with a stirrer and a condenser, 85 g of deionized water, 1.4 g of emulsifier (octylphenol polyoxyethylene ether OP-10), 0.35 g of sodium dodecyl sulfate SDS, 0.3 g of sodium bicarbonate buffer, and 2 g of a part of monomer mixture were added, and stirred and dispersed uniformly, then heated to 60°C using a water bath, 0.175 g of initiator ammonium persulfate APS (dissolved in 20 mL of water) was added, and the temperature was further increased to 70°C, then the remaining monomer mixture was added dropwise, 2 hours for dropwise addition, then the temperature was maintained for 1 hour, then 0.05 g of initiator ammonium sulfate APS (dissolved in 10 mL of water) was added, then the temperature was increased to 80°C for 2 hours of curing, the reaction was completed, the temperature was decreased to room temperature, and the product was discharged. The raw materials of the monomer mixture were 15 g of acetoacetoxy methyl acrylate AAEM, 31 g of methyl methacrylate MMA, 32 g of acrylic acid AA, 1.4 g of octylphenol polyoxyethylene ether OP-10, 0.35 g of sodium dodecyl sulfate SDS, and 80 mL of water.

[0083] In the above Examples 1-5, the preparation method of γ-aminopropyl triethoxysilane modified kaolin and γ-aminopropyl triethoxysilane modified titanium dioxide was as follows: 2-3 parts of titanium dioxide or calcined kaolin, 0.06-0.12 parts of γ-aminopropyl triethoxysilane, 14-16 parts of deionized water, and 18-22 parts of anhydrous ethanol were mixed, the pH was adjusted to 4-6 using glacial acetic acid and 25% ammonia water, and then ultrasonic dispersion was performed at 40-45°C and 50-60 Hz for 50-70 min, followed by washing, filtration, and drying.

[0084] The specific preparation parameters of the gamma-aminopropyl triethoxysilane modified kaolin and the gamma-aminopropyl triethoxysilane modified titanium dioxide in each of embodiments 1-5 are shown in Table 5:

[0085] Table 5 Preparation parameters of gamma-aminopropyl triethoxysilane modified color fillers

[0086]

[0087] The preparation method of the self-crosslinking multi-color paint of embodiments 1-5 is as follows:

[0088] The sand-containing color dot base paint is added to the granulation liquid, granulated, and then added to the continuous phase, mixed uniformly to obtain the self-crosslinking multi-color paint.

[0089] Embodiments 6-12

[0090] Embodiments 6-12 of the present application provide a self-crosslinking multi-color paint, the raw materials, mass fractions, mass ratios, and preparation methods are the same as those of embodiment 2, and the difference lies in that the preparation method of the gamma-aminopropyl triethoxysilane modified kaolin is as follows: 3 parts of calcined kaolin, 0.08 parts of gamma-aminopropyl triethoxysilane, 15 parts of deionized water, and 20 parts of anhydrous ethanol are mixed, the pH is adjusted with ice acetic acid and 25% ammonia water (as shown in Table 6), and ultrasonic dispersion is carried out at 45°C for 60Hz for 70 minutes, and then washed, filtered, and dried to obtain the product.

[0091] Table 6 Preparation parameters of gamma-aminopropyl triethoxysilane modified kaolin in embodiments 6-12

[0092] Example 6 Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 pH 3.0 3.5 4.0 4.5 5.0 5.5 6.0

[0093] Embodiments 13-19

[0094] Embodiments 13-19 of the present application provide a self-crosslinking multi-color paint, the raw materials, mass fractions, mass ratios, and preparation methods are the same as those of embodiment 2, and the difference lies in that the preparation method of the gamma-aminopropyl triethoxysilane modified kaolin is as follows: 3 parts of calcined kaolin, 0.08 parts of gamma-aminopropyl triethoxysilane, 15 parts of deionized water, and 20 parts of anhydrous ethanol are mixed, the pH is adjusted to 4.5 with ice acetic acid and 25% ammonia water, and ultrasonic dispersion is carried out at different temperatures (as shown in Table 7) for 60Hz for 70 minutes, and then washed, filtered, and dried to obtain the product.

[0095] Table 7 Preparation parameters of gamma-aminopropyl triethoxysilane modified kaolin in embodiments 13-19

[0096]

[0097] Embodiments 20-23

[0098] Embodiments 20-23 of the present application provide a self-crosslinking multi-color paint, the raw materials, mass fraction, mass ratio and preparation method are the same as those of Embodiment 2, and the difference lies in that the preparation method of the γ-aminopropyl triethoxysilane modified kaolin is as follows: 3 parts of calcined kaolin, 0.08 parts of γ-aminopropyl triethoxysilane, 15 parts of deionized water and 20 parts of anhydrous ethanol are mixed, the pH is adjusted to 4.5 with glacial acetic acid and 25% ammonia water, and ultrasonic dispersion is carried out at 45°C and 60Hz for different times (as shown in Table 8), and then washing, filtering and drying are carried out to obtain the product.

[0099] Table 8 Preparation parameters of γ-aminopropyl triethoxysilane modified kaolin in Embodiments 20-23

[0100] Example 20 Example 21 Example 22 Example 23 Ultrasonic time (min) 50 70 90 110

[0101] Embodiments 24-32

[0102] Embodiments 24-32 of the present application provide a self-crosslinking multi-color paint, the raw materials, mass fraction, mass ratio and preparation method are the same as those of Embodiment 2, and the difference lies in that the preparation method of the γ-aminopropyl triethoxysilane modified kaolin is as follows: 3 parts of calcined kaolin, different amounts of γ-aminopropyl triethoxysilane (as shown in Table 9), 15 parts of deionized water and 20 parts of anhydrous ethanol are mixed, the pH is adjusted to 4.5 with glacial acetic acid and 25% ammonia water, and ultrasonic dispersion is carried out at 45°C and 60Hz for different times, and then washing, filtering and drying are carried out to obtain the product.

[0103] Table 9 Preparation parameters of γ-aminopropyl triethoxysilane modified kaolin in Embodiments 24-32

[0104]

[0105]

[0106] Note: The amount of γ-aminopropyl triethoxysilane (%): the percentage of the mass of γ-aminopropyl triethoxysilane relative to the mass of calcined kaolin.

[0107] Comparative Example 1

[0108] This comparative example provides a self-crosslinking multi-color paint, the raw materials and preparation method are basically the same as those of Embodiment 2, and the difference lies in that the multi-color base paint emulsion containing acetoacetyl groups in the sand-containing color dot base paint is replaced by a common base paint emulsion (2788).

[0109] Comparative Example 2

[0110] This comparative example provides a self-crosslinking multi-color paint, the raw materials and preparation method are basically the same as those of Embodiment 2, and the difference lies in that the γ-aminopropyl triethoxysilane modified color and filler is replaced by a common color and filler calcined kaolin.

[0111] Comparative Example 3

[0112] This comparative example provides a self-crosslinking multicolor paint, the raw materials and preparation method are basically the same as Example 2, the difference is that the continuous phase emulsion containing acetoacetoxy in the continuous phase is replaced by the ordinary base paint emulsion (2788).

[0113] Comparative Example 4

[0114] This comparative example provides a self-crosslinking multicolor paint, the raw materials and preparation method are basically the same as Example 2, the difference is that the multicolor base paint emulsion containing acetoacetoxy in the sand-containing color dot base paint is replaced by the ordinary base paint emulsion (2788), the γ-aminopropyl triethoxysilane modified pigment and filler is replaced by the ordinary pigment and filler calcined kaolin, and the continuous phase emulsion containing acetoacetoxy in the continuous phase is replaced by the ordinary base paint emulsion (2788).

[0115] Comparative Example 5

[0116] This comparative example provides a γ-aminopropyl triethoxysilane modified kaolin, the preparation method is: 3 parts of calcined kaolin, 0.08 parts of γ-aminopropyl triethoxysilane, 15 parts of deionized water, 20 parts of anhydrous ethanol are mixed, the pH is adjusted to 6.5 with ice acetic acid and 25% ammonia water, and then dispersed at 45°C for 60Hz for 70min, washed, filtered and dried.

[0117] Comparative Example 6

[0118] This comparative example provides a γ-aminopropyl triethoxysilane modified kaolin, the preparation method is: 3 parts of calcined kaolin, 0.08 parts of γ-aminopropyl triethoxysilane, 15 parts of deionized water, 20 parts of anhydrous ethanol are mixed, the pH is adjusted to 7.0 with ice acetic acid and 25% ammonia water, and then dispersed at 45°C for 60Hz for 70min, washed, filtered and dried.

[0119] Comparative Example 7

[0120] This comparative example provides a γ-aminopropyl triethoxysilane modified kaolin, the preparation method is: 3 parts of calcined kaolin, 0.08 parts of γ-aminopropyl triethoxysilane, 15 parts of deionized water, 20 parts of anhydrous ethanol are mixed, the pH is adjusted to 4.5 with ice acetic acid and 25% ammonia water, and then dispersed at 45°C for 60Hz for 10min, washed, filtered and dried.

[0121] Comparative Example 8

[0122] The comparative example 1 provides a γ-aminopropyl triethoxysilane modified kaolin, and the preparation method is as follows: 3 parts of calcined kaolin, 0.08 parts of γ-aminopropyl triethoxysilane, 15 parts of deionized water and 20 parts of anhydrous ethanol are mixed, the pH is adjusted to 4.5 by using ice acetic acid and 25% ammonia water, and then ultrasonic dispersion is carried out at 45°C and 60Hz for 30 minutes, and then washing, filtering and drying are carried out to obtain the product.

[0123] Comparative example 9

[0124] The comparative example 1 provides a γ-aminopropyl triethoxysilane modified kaolin, and the preparation method is as follows: 3 parts of calcined kaolin, 0.08 parts of γ-aminopropyl triethoxysilane, 15 parts of deionized water and 20 parts of anhydrous ethanol are mixed, the pH is adjusted to 4.5 by using ice acetic acid and 25% ammonia water, and then ultrasonic dispersion is carried out at 45°C and 60Hz for 30 minutes, and then washing, filtering and drying are carried out to obtain the product.

[0125] Comparative example 10

[0126] The comparative example 1 provides a γ-aminopropyl triethoxysilane modified kaolin, and the preparation method is as follows: 3 parts of calcined kaolin, 0.08 parts of γ-aminopropyl triethoxysilane, 15 parts of deionized water and 20 parts of anhydrous ethanol are mixed, the pH is adjusted to 4.5 by using ice acetic acid and 25% ammonia water, and then ultrasonic dispersion is carried out at 45°C and 60Hz for 30 minutes, and then washing, filtering and drying are carried out to obtain the product.

[0127] Comparative example 11

[0128] The comparative example 1 provides a γ-aminopropyl triethoxysilane modified kaolin, and the preparation method is as follows: 3 parts of calcined kaolin, 0.08 parts of γ-aminopropyl triethoxysilane, 15 parts of deionized water and 20 parts of anhydrous ethanol are mixed, the pH is adjusted to 4.5 by using ice acetic acid and 25% ammonia water, and then ultrasonic dispersion is carried out at 45°C and 60Hz for 30 minutes, and then washing, filtering and drying are carried out to obtain the product.

[0129] Test example 1

[0130] The tests of various items are carried out according to the following steps:

[0131] The self-crosslinking multi-color paints prepared in examples 1-3 and comparative examples 1-4 are sprayed on standard samples or blocks coated with colored primer, dried for 24h under standard environment, and then immersed in deionized water for 12h after being sealed with rosin paraffin on the edges and back. The water whitening resistance, peeling difficulty of color dots and paint film, color dot hardness and paint film state after water resistance test of the samples are characterized respectively.

[0132] The self-crosslinking multicolor paints prepared from Examples 1 to 3 and Comparative Examples 1 to 4 were sprayed on standard panels or plaques coated with a colored base coat, dried for 24 h under standard conditions, and subjected to a stain resistance test.

[0133] The adhesive strength and water resistance were tested according to JG / T 24 and HG / T 4343.

[0134] The results are shown in Table 10.

[0135] Table 10 Performance test results of Examples 1 to 3 and Comparative Examples 1 to 4

[0136]

[0137]

[0138] Test Example 2

[0139] This test example investigated the sedimentation performance of the γ-aminopropyl triethoxysilane modified pigment and filler prepared under different preparation parameters. The effect of silane modification was evaluated by the dispersion time of the modified pigment and filler in acetone, and the longer the sedimentation time, the better the modification effect.

[0140] Examples 6 to 12 and Comparative Examples 5 and 6 respectively prepared γ-aminopropyl triethoxysilane modified kaolin at different pH values, and the results are shown in Table 3. Figure 9 When the pH was higher, the sedimentation performance of the obtained γ-aminopropyl triethoxysilane modified kaolin decreased.

[0141] Examples 13 to 19 respectively prepared γ-aminopropyl triethoxysilane modified kaolin at different temperatures, and the results are shown in Table 4. Figure 10 When the modification was carried out at 40 to 45°C, better sedimentation performance was obtained.

[0142] Examples 20 to 23 and Comparative Examples 7 and 8 respectively prepared γ-aminopropyl triethoxysilane modified kaolin at different ultrasonic dispersion times, and the results are shown in Table 5. Figure 11 When the ultrasonic time was shorter, the sedimentation performance of the obtained γ-aminopropyl triethoxysilane modified kaolin was poorer.

[0143] Examples 24 to 32 and Comparative Examples 9 to 11 respectively prepared γ-aminopropyl triethoxysilane modified kaolin at different amounts of silane coupling agent, and the results are shown in Table 6. Figure 12 When the amount of silane coupling agent was smaller, the sedimentation performance of the obtained γ-aminopropyl triethoxysilane modified kaolin was poorer.

[0144] The above merely provides the preferred embodiment of the present application, and is not used to limit the present application, and any modification, equivalent replacement or improvement made in the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A self-crosslinking multicolor paint, characterized by, The sand-containing color dot base paint, the granulation liquid and the continuous phase; the mass ratio of the three is (54-66):(18-22):(18-22); The sand-containing color dot base paint comprises the following raw materials in parts by mass: acetoacetyl group-containing multi-color base paint emulsion 9-12 parts; gamma-aminopropyl triethoxysilane modified pigment and filler 2.5-4 parts; hydroxyethyl cellulose 0.4-0.8 parts; film forming aid 0.4-0.7 parts; pH regulator 0.03-0.05 parts; Dispersant 0.04-0.08 parts; defoaming agent 0.2-0.3 parts; protective peptizing solution 2.5-4.5 parts; quartz sand 20-30 parts; water 10-22 parts; The granulation liquid comprises the following raw materials in parts by mass: protective peptizing solution 9-12.5 parts, anti-settling agent 0.06-0.1 parts, water 7-11 parts; The continuous phase comprises the following raw materials in parts by mass: acetoacetyl group-containing continuous phase emulsion 12-15 parts, film forming aid 0.5-0.8 parts, pH regulator 0.05-0.1 parts, defoaming agent 0.05-0.1 parts, thickening agent 0.15-0.3 parts, water 3-6.5 parts; The acetoacetyl group-containing multi-color base paint emulsion is a pure acrylic emulsion or a silicone-acrylic emulsion modified by an acetoacetyl group; the acetoacetyl group-containing continuous phase emulsion is a pure acrylic emulsion or a silicone-acrylic emulsion modified by an acetoacetyl group; and the gamma-aminopropyl triethoxysilane modified pigment and filler is at least one of gamma-aminopropyl triethoxysilane modified titanium dioxide or calcined kaolin.

2. The self-crosslinking multicolor paint according to claim 1, characterized by, The sand-containing color dot base paint further comprises at least one of the following raw materials in parts by mass: antifreeze 0.3-0.6 parts, bactericide 0.15-0.3 parts; and / or The granulation liquid further comprises bactericide 0.1-0.15 parts in parts by mass; and / or The continuous phase further comprises at least one of the following raw materials in parts by mass: antifreeze 0.3-0.6 parts, bactericide 0.1-0.2 parts.

3. The self-crosslinking multicolor paint according to claim 1, characterized by, The mass ratio of the sand-containing color dot base paint, the granulation liquid and the continuous phase is 60:20:

20.

4. The self-crosslinking multicolor paint according to any one of claims 1 to 3, characterized in that, The hydroxyethyl cellulose is of type 250HBR, 250HHBR or 10K; and / or The film forming aid is alcohol ester twelve; and / or The dispersant is a sodium carboxylate dispersant or an ammonium carboxylate dispersant; and / or The defoaming agent is a silicone or mineral oil-based defoaming agent; and / or The protective peptizing solution is a 8%-10%wt lithium magnesium silicate aqueous solution; and / or The anti-settling agent is xanthan gum; and / or The pH regulator is sodium bicarbonate; and / or The thickening agent is an alkali-swellable acrylic thickening agent.

5. The self-crosslinking multicolor paint according to claim 4, characterized in that, The acetoacetoxy-containing multi-color base paint emulsion comprises the following raw materials in parts by mass: deionized water 95-110 parts, emulsifier 1.5-2.0 parts, sodium bicarbonate buffer 0.3-0.35 parts, monomer mixture 146-182.5 parts, and initiator 0.21-0.24 parts; wherein the monomer mixture comprises the following raw materials in parts by mass: acetoacetoxy ethyl methacrylate 12-18 parts, methyl methacrylate 28-35 parts, butyl acrylate 38-45 parts, emulsifier 1.5-2.0 parts, and water 65-80 parts; and / or The acetoacetoxy-containing continuous phase emulsion comprises the following raw materials in parts by mass: deionized water 110-120 parts, emulsifier 1.5-2.0 parts, sodium bicarbonate buffer 0.3-0.35 parts, monomer mixture 150-180.5 parts, and initiator 0.21-0.24 parts; wherein the monomer mixture comprises the following raw materials in parts by mass: acetoacetoxy ethyl methacrylate 12-18 parts, methyl methacrylate 30-35 parts, acrylic acid 30-38 parts, emulsifier 1.5-2.0 parts, and water 75-85 parts.

6. The self-crosslinking multicolor paint according to claim 5, characterized by, The emulsifier is octylphenol polyoxyethylene ether and sodium dodecyl sulfate in a mass ratio of 3.4-5.2:1; and / or The initiator is ammonium persulfate.

7. The self-crosslinking multicolor paint according to claim 1, characterized by, The preparation method of the γ-aminopropyl triethoxysilane modified pigment and filler is as follows: titanium white or calcined kaolin, γ-aminopropyl triethoxysilane, deionized water, and anhydrous ethanol are mixed, the pH is adjusted to 3-6 with glacial acetic acid and ammonia water, and then ultrasonic dispersion is performed at 30-60℃ for 50-60 Hz for at least 50 min, and then washing, filtering, and drying are performed to obtain the product; the mass of the γ-aminopropyl triethoxysilane is 2%-6% of the mass of the titanium white or calcined kaolin.

8. The self-crosslinking multicolor paint according to claim 7, characterized by, The pH is adjusted to 4-6; and / or Ultrasonic dispersion is performed at 40-45℃; and / or The mass of the γ-aminopropyl triethoxysilane is 3%-4.5% of the mass of the titanium white or calcined kaolin.

9. Process for the preparation of a self-crosslinking multicolor paint according to any one of claims 1 to 8, characterized in that, The method specifically comprises the following operation: the sand-containing color point base paint is added to the granulation liquid, granulation is performed, and then the product is added to the continuous phase, mixed uniformly, to obtain the self-crosslinking multi-color paint.

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