Waterproof heat-resistant mold coating and preparation method thereof

Abstract

The invention provides a waterproof heat-resistant mold coating which comprises the following components: modified acrylic resin, modified silicon dioxide, epoxy resin, kaolin, talcum powder, hexagonal boron nitride, zinc stearate, graphite, a solvent and an auxiliary agent, wherein the modified acrylic resin is obtained by polymerizing acrylic acid and butyl methacrylate and then grafting 2-fluoro-5-(trifluoromethyl) benzyl alcohol and triisopropyl silanol; the modified silicon dioxide is obtained by grafting perfluorooctyl ethylene, phenyl methacrylate, hydroxyethyl methylacrylate and oleic acid after silicon dioxide and a silane coupling agent react with each other. According to the waterproof heat-resistant mold coating disclosed by the invention, a silicon-oxygen bond, a benzene ring, a long fluorine chain and an organic chain segment are introduced into the modified silicon dioxide, and the silicon-oxygen bond, the benzene ring, the fluorine chain and the organic chain segment are introduced into the modified acrylic resin, so that the heat resistance, hydrophobicity and other properties of the coating are improved, and the waterproof heat-resistant mold coating has a good application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metal high-temperature protection, and mainly relates to a waterproof heat-resistant mold coating and a preparation method thereof. BACKGROUND

[0002] A mold is a tool for forming a workpiece, and a stamping die is an important component thereof. The stamping die is important process equipment for forming metal or non-metal materials in industrial production. By applying pressure through a press, plastic deformation or separation of the material occurs, thereby obtaining a part with a desired shape. The technical features include: high production efficiency, with tens to hundreds of parts processed per minute; stable product precision, with a size tolerance of ±0.01 mm; high material utilization, with a reasonable layout of 70-85%; and suitability for mass production.

[0003] The composition structure of the stamping die includes an upper die, a lower die, a guide system, and working parts. According to the process properties, the stamping die can be classified into blanking dies, bending dies, drawing dies, forming dies, etc. According to the structural complexity, the stamping die can be classified into single-process dies, compound dies, progressive dies, etc. The product application of the stamping die is wide, including: automobile manufacturing, body parts (doors, engine covers), chassis parts, etc.; electronics / electrical appliances, housings, circuit boards, heat sinks, etc.; building hardware, steel structures, door and window accessories, etc.; medical devices, surgical instruments, precision parts, etc.

[0004] However, there are some problems in the use of stamping dies, especially the adverse effects of high temperature and moisture on stamping dies, including: (1) high temperature aggravates the wear of the stamping die. Continuous stamping generates heat due to friction, causing the temperature of the die to rise. Without the protection of a heat-resistant coating, long-term high-temperature stamping friction can cause the blade edge or cavity to collapse or peel off, affecting product quality; (2) moisture causes corrosion and oxidation of the stamping die. Moisture contact with the stamping die can cause the surface of the die to rust, leading to size deviation and surface roughness, affecting product quality.

[0005] In view of the above, it is necessary to develop a new technical solution to solve the defects and deficiencies in the prior art. SUMMARY

[0006] The present application provides a waterproof heat-resistant mold coating, which contains modified acrylic resin, modified silicon dioxide and other components. By introducing silicon-oxygen bonds, benzene rings, long fluorine chains, and organic chain segments, the heat resistance and hydrophobicity of the coating are improved, solving the deficiencies of the prior art and having good application prospects.

[0007] An object of the present application is to provide a waterproof heat-resistant mold coating, which comprises the following components by mass fraction:

[0008]

[0009]

[0010] The modified acrylic resin is obtained by grafting 2-fluoro-5-(trifluoromethyl) benzyl alcohol and triisopropylsilanol after polymerization of acrylic acid and butyl methacrylate; the modified silica is obtained by grafting perfluorooctyl ethylene, phenyl methacrylate, hydroxyethyl methacrylate and oleic acid after reaction of silica and silane coupling agent.

[0011] Further, the solvent is selected from one or more of ester, ketone or ether ester solvents.

[0012] Further, the auxiliary agent is selected from one or more of dispersant, curing agent, lubricant and film forming auxiliary agent.

[0013] Another object of the present application is to provide a preparation method of the waterproof heat-resistant mold coating, which comprises the following steps:

[0014] S1, blending silica and silane coupling agent, heating and stirring to obtain intermediate product 1;

[0015] S2, under inert atmosphere, blending perfluorooctyl ethylene, phenyl methacrylate, hydroxyethyl methacrylate, oleic acid, initiator 1 and intermediate product 1, heating and stirring to obtain modified silica;

[0016] S3, blending acrylic acid, butyl methacrylate and initiator 2, heating and stirring to obtain intermediate product 2, then adding 2-fluoro-5-(trifluoromethyl) benzyl alcohol, triisopropylsilanol and catalyst, heating and stirring to obtain modified acrylic resin;

[0017] S4, blending and stirring the modified silica, modified acrylic resin and the remaining components to obtain the waterproof heat-resistant mold coating.

[0018] Further, in step S1, the mass ratio of the silica and the silane coupling agent is (5-10):(8-15).

[0019] Further, in step S1, the temperature of the heating and stirring is 40-60℃.

[0020] Further, in step S2, the mass ratio of the perfluorooctyl ethylene, phenyl methacrylate, hydroxyethyl methacrylate, oleic acid and intermediate product 1 is (10-14):(10-15):(10-15):(3-7):(1-5).

[0021] Further, in step S2, the heating temperature is 80-120℃.

[0022] Further, in step S3, the mass ratio of the acrylic acid, butyl methacrylate, 2-fluoro-5-(trifluoromethyl) benzyl alcohol, triisopropylsilanol is (40-50):(4-8):(13-20):(5-10).

[0023] Further, in step S3, the heating and stirring temperature is 70-90℃, and the blending heating and stirring temperature is 130-170℃.

[0024] The present application has the following beneficial effects:

[0025] The waterproof heat-resistant mold coating provided by the present application is composed of modified acrylic resin, modified silicon dioxide and other components. The present application first reacts silicon dioxide with silane coupling agent, and then reacts with perfluoro octyl ethylene, phenyl methacrylate, hydroxyethyl methacrylate and oleic acid to obtain modified silicon dioxide. Silicon-oxygen bond, benzene ring, long fluorine chain and organic chain segment are introduced into the modified silicon dioxide. The silicon-oxygen bond has high bond energy, which is conducive to the stability of the modified silicon dioxide at high temperature and improves the heat resistance of the modified silicon dioxide. The rigid structure of the benzene ring is also conducive to improving the thermal stability of the coating. The long fluorine chain has low surface energy, which can improve the hydrophobicity of the coating. Moreover, the carbon-fluorine bond in the long fluorine chain also has high bond energy, which can have a synergistic effect with the silicon-oxygen bond and the benzene ring to improve the heat resistance of the coating. The organic chain segment is interpenetrated with the remaining components to avoid agglomeration and improve the compatibility of the components, thereby improving the performance of the product. After the acrylic acid and butyl methacrylate are polymerized, 2-fluoro-5-(trifluoromethyl) benzyl alcohol and triisopropylsilanol are grafted to obtain modified acrylic resin. Silicon-oxygen bond, benzene ring, fluorine chain and organic chain segment are introduced into the modified acrylic resin. The principle is the same as described above, which improves the heat resistance, hydrophobicity and other properties of the coating. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 The heat resistance test result photos of Example 1 in the test example are shown.

[0027] Figure 2 The water resistance test result photos of Example 1 in the test example are shown. DETAILED DESCRIPTION

[0028] In order to more clearly illustrate the technical solutions of the present application, the following examples are listed. The raw materials, reactions and post-treatment methods appearing in the examples are all common raw materials on the market and technical means familiar to those skilled in the art, unless otherwise stated.

[0029] The words "preferred" and "preferably" in the application refer to embodiments of the application that can provide certain benefits under certain circumstances. However, other embodiments can also be preferred under the same or other circumstances. Additionally, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude those other embodiments from the scope of the application.

[0030] It should be understood that, except where noted otherwise, expressions of amount or all numbers in the specification and claims, such as, for example, amounts of ingredients, should be understood as being modified by the term "about" in all instances. Accordingly, unless indicated otherwise, the numerical parameters set forth in the following specification and attached claims are approximations.

[0031] The following raw materials are used in the embodiments of the application:

[0032] KH570, silane coupling agent;

[0033] Molybdenum disulfide, lubricant;

[0034] Ethyl acetate, solvent;

[0035] Dimethyl imidazole, curing agent;

[0036] 4-Dimethylamino pyridine, catalyst;

[0037] Potassium persulfate is initiator 1;

[0038] Hydrogen peroxide is initiator 2;

[0039] Epoxy resin, model SILIKOPON EF, purchased from Yincun Special Chemical (Shanghai) Co., Ltd.

[0040] Example 1

[0041] A waterproof heat-resistant mold coating, the waterproof heat-resistant mold coating comprising components in the following mass fractions:

[0042]

[0043] A method for preparing the waterproof heat-resistant mold coating described above, comprising the following steps:

[0044] S1, ethanol and water in a volume ratio of 1:1 are used as solvents, silica and KH570 in a mass ratio of 5:8 are added, heated to 50°C and stirred for 24h, filtered, washed and dried to obtain intermediate product 1;

[0045] S2, under a nitrogen atmosphere, the mass ratio of perfluoro octyl ethylene, phenyl methacrylate, hydroxyethyl methacrylate, oleic acid, potassium persulfate, intermediate product 1 is 12:12:12:5:0.5:3, blend with water as solvent, heated to 80℃ and stirred for 4h, after filtration, washing, drying, modified silica is obtained;

[0046] S3, with ethanol as solvent, the mass ratio of acrylic acid, butyl methacrylate, hydrogen peroxide is 50:7:3, blend, heated to 80℃ and stirred for 4h, intermediate product 2 is obtained, then 2-fluoro-5-(trifluoromethyl) benzyl alcohol, triisopropyl silanol, 4-dimethyl amino pyridine (the mass ratio of acrylic acid, 2-fluoro-5-(trifluoromethyl) benzyl alcohol, triisopropyl silanol, 4-dimethyl amino pyridine is 50:16:7:2) is added, blend, heated to 150℃ and stirred for 3h, modified acrylic resin is obtained;

[0047] S4, according to the above mass fraction, the modified silica, modified acrylic resin and the rest of the components are blended and stirred to obtain the waterproof heat-resistant mold coating.

[0048] Example 2

[0049] A waterproof heat-resistant mold coating, the waterproof heat-resistant mold coating, comprising components in the following mass fraction:

[0050]

[0051] The preparation method of the above waterproof heat-resistant mold coating, comprising the following steps:

[0052] S1, with ethanol and water as solvent in the volume ratio of 1:1, adding silica and KH570 in the mass ratio of 7:8, heated to 50℃ and stirred for 24h, after filtration, washing, drying, intermediate product 1 is obtained;

[0053] S2, under a nitrogen atmosphere, the mass ratio of perfluoro octyl ethylene, phenyl methacrylate, hydroxyethyl methacrylate, oleic acid, potassium persulfate, intermediate product 1 is 12:12:12:5:0.5:3, blend with water as solvent, heated to 80℃ and stirred for 4h, after filtration, washing, drying, modified silica is obtained;

[0054] S3, with ethanol as the solvent, acrylic acid, butyl methacrylate, hydrogen peroxide with a mass ratio of 50:8:3 were blended, heated to 80°C and stirred for 4h to obtain intermediate product 2, then 2-fluoro-5-(trifluoromethyl) benzyl alcohol, triisopropylsilanol, 4-dimethylamino pyridine (the mass ratio of acrylic acid, 2-fluoro-5-(trifluoromethyl) benzyl alcohol, triisopropylsilanol, 4-dimethylamino pyridine was 50:16:7:2) were blended, heated to 150°C and stirred for 3h to obtain the modified acrylic resin;

[0055] S4, according to the above mass fraction, the modified silica, the modified acrylic resin and the remaining components were blended and stirred to obtain the waterproof heat-resistant mold coating.

[0056] Example 3

[0057] A waterproof heat-resistant mold coating, the waterproof heat-resistant mold coating, comprising components in the following mass fractions:

[0058]

[0059]

[0060] The preparation method of the above waterproof heat-resistant mold coating, comprising the following steps:

[0061] S1, with ethanol and water with a volume ratio of 1:1 as the solvent, silica and KH570 with a mass ratio of 5:8 were added, heated to 60°C and stirred for 24h, then filtered, washed and dried to obtain intermediate product 1;

[0062] S2, under a nitrogen atmosphere, perfluorooctyl vinyl, phenyl methacrylate, hydroxyethyl methacrylate, oleic acid, potassium persulfate, intermediate product 1 with a mass ratio of 12:12:12:6:0.5:3 were blended with water as the solvent, heated to 90°C and stirred for 4h, then filtered, washed and dried to obtain the modified silica;

[0063] S3, with ethanol as the solvent, acrylic acid, butyl methacrylate, hydrogen peroxide with a mass ratio of 50:7:3 were blended, heated to 80°C and stirred for 4h to obtain intermediate product 2, then 2-fluoro-5-(trifluoromethyl) benzyl alcohol, triisopropylsilanol, 4-dimethylamino pyridine (the mass ratio of acrylic acid, 2-fluoro-5-(trifluoromethyl) benzyl alcohol, triisopropylsilanol, 4-dimethylamino pyridine was 50:16:8:2) were blended, heated to 150°C and stirred for 3h to obtain the modified acrylic resin;

[0064] S4, according to the above mass fraction, the modified silica, the modified acrylic resin and the remaining components were blended and stirred to obtain the waterproof heat-resistant mold coating.

[0065] Comparative Example 1

[0066] Comparative Example 1 differs from Example 1 in that the triisopropylsilanol in step S3 is deleted, and the remaining components and preparation method are the same as in Example 1.

[0067] Comparative Example 2

[0068] Comparative Example 2 differs from Example 1 in that the phenyl methacrylate in step S2 is replaced by methyl methacrylate, and the remaining components and preparation method are the same as in Example 1.

[0069] Comparative Example 3

[0070] Comparative Example 3 differs from Example 1 in that the phenyl methacrylate and the hydroxyethyl methacrylate in step S2 are deleted, and the remaining components and preparation method are the same as in Example 1.

[0071] Test Example

[0072] The properties of the coatings obtained from the paint samples of Test Examples 1-3 and Comparative Examples 1-3 were tested.

[0073] Test Method:

[0074] After the tinplate sheet surface was polished and cleaned, the paint samples were respectively coated, and the coatings were obtained after curing at 150°C.

[0075] The heat resistance of the coatings obtained from the paint samples of Test Examples 1-3 and Comparative Examples 1-3 was tested according to GB / T 1735, with the condition being 120h at 250°C.

[0076] The water resistance of the coatings obtained from the paint samples of Test Examples 1-3 and Comparative Examples 1-3 was tested according to GB / T 1733, with the condition being 200h of immersion.

[0077] The adhesion of the coatings obtained from the paint samples of Test Examples 1-3 and Comparative Examples 1-3 was tested according to GB / T 1720.

[0078] The impact resistance of the coatings obtained from the paint samples of Test Examples 1-3 and Comparative Examples 1-3 was tested according to GB / T 1732, with the condition being 60kg·cm of positive and reverse impact.

[0079] Test Results:

[0080] Table 1 shows the test results of the properties of the coatings obtained from the paint samples of Test Examples 1-3 and Comparative Examples 1-3.

[0081] Table 1 Test results of the properties of the coatings obtained from the paint samples of Test Examples 1-3 and Comparative Examples 1-3

[0082] Item Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Heat resistance No peeling No peeling No peeling Little peeling Little peeling Little peeling Water resistance No change No change No change No change No change Local yellowing Adhesion 1st 1st 1st 1st 1st 2nd Impact resistance No cracking No cracking No cracking No cracking Little cracking Little cracking

[0083] As can be seen from Table 1, the heat resistance, water resistance, adhesion, and impact resistance of Examples 1-3 are good, and are all superior to those of Comparative Examples 1-4. This is because the modified acrylic resin in Comparative Example 1 does not contain siloxane bonds, which reduces the heat resistance of the product, the modified silica in Comparative Example 2 does not have benzene rings introduced, which reduces the heat resistance and impact resistance of the product, and the modified silica in Comparative Example 3 does not have benzene rings and acrylic ester groups introduced, which reduces the compatibility of the modified silica with the modified acrylic resin and other components, which is not conducive to uniform dispersion of the components, resulting in a decrease in the heat resistance, water resistance, adhesion, and impact resistance of the product.

[0084] It will be obvious to a person skilled in the art that, without departing from the spirit or essential characteristics of the application, the present application can be implemented in other specific forms. The present examples are therefore to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the specification as such. All changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

[0085] Furthermore, it should be understood that although the description herein is made on the basis of the embodiments, not every embodiment contains only one independent technical solution, and the description herein is made in this way only for the sake of clarity, and a person skilled in the art should consider the description as a whole, and the technical solutions in each embodiment can also be combined appropriately to form other embodiments that can be understood by a person skilled in the art.

Claims

1. A waterproof and heat-resistant mold coating, characterized in that: The waterproof and heat-resistant mold coating comprises the following components in parts by mass: The modified acrylic resin is obtained by polymerizing acrylic acid and butyl methacrylate and then grafting 2-fluoro-5-(trifluoromethyl)benzyl alcohol and triisopropylsilanol; the modified silica is obtained by reacting silica and a silane coupling agent and then grafting perfluorooctylethylene, phenyl methacrylate, hydroxyethyl methacrylate and oleic acid.

2. The waterproof and heat-resistant mold coating according to claim 1, characterized in that: The solvent is selected from one or more of ester, ketone or ether ester solvents.

3. The waterproof and heat-resistant mold coating according to claim 1, characterized in that: The auxiliary agent is selected from one or more of a dispersant, a curing agent, a lubricant, and a film-forming auxiliary agent.

4. The method for preparing the waterproof and heat-resistant mold coating according to any one of claims 1 to 3, characterized in that: The preparation method of the waterproof and heat-resistant mold coating comprises the following steps: S1, mixing silicon dioxide and a silane coupling agent, heating and stirring, and reacting to obtain an intermediate product 1; S2. Under an inert atmosphere, perfluorooctylethylene, phenyl methacrylate, hydroxyethyl methacrylate, oleic acid, initiator 1, and intermediate 1 are mixed and heated with stirring to react to obtain modified silica; S3, acrylic acid, butyl methacrylate, and initiator 2 are blended, heated and stirred, and reacted to obtain intermediate product 2, and then 2-fluoro-5-(trifluoromethyl)benzyl alcohol, triisopropylsilanol, and a catalyst are added, blended, heated and stirred, and reacted to obtain a modified acrylic resin; S4. Blending and stirring the modified silica, modified acrylic resin and other components to obtain the waterproof and heat-resistant mold coating.

5. The method for preparing the waterproof and heat-resistant mold coating according to claim 4, characterized in that: In step S1, the mass ratio of the silicon dioxide to the silane coupling agent is (5-10):(8-15).

6. The method for preparing the waterproof and heat-resistant mold coating according to claim 4, characterized in that: In step S1, the temperature of the heating and stirring is 40-60°C.

7. The method for preparing the waterproof and heat-resistant mold coating according to claim 4, characterized in that: In step S2, the mass ratio of perfluorooctylethylene, phenyl methacrylate, hydroxyethyl methacrylate, oleic acid, and intermediate product 1 is (10-14):(10-15):(10-15):(3-7):(1-5).

8. The method for preparing the waterproof and heat-resistant mold coating according to claim 4, characterized in that: In step S2, the heating temperature is 80-120°C.

9. The method for preparing the waterproof and heat-resistant mold coating according to claim 4, characterized in that: In step S3, the mass ratio of acrylic acid, butyl methacrylate, 2-fluoro-5-(trifluoromethyl)benzyl alcohol, and triisopropylsilanol is (40-50):(4-8):(13-20):(5-10).

10. The method for preparing the waterproof and heat-resistant mold coating according to claim 4, characterized in that: In step S3, the temperature for heating and stirring is 70-90°C, and the temperature for blending, heating and stirring is 130-170°C.

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