Coating and preparation method thereof

Abstract

The invention provides a coating and a preparation method thereof. The coating comprises the following raw materials in parts by weight: 1-5 parts of graphene, 10-30 parts of a fluorine-containing monomer, 2-8 parts of an auxiliary agent, 30-60 parts of a solvent and 2-5 parts of a curing agent. The assistant effectively improves the dispersity of the graphene in a coating system, avoids agglomeration of the graphene, so that the graphene can be uniformly dispersed in the coating to form a compact barrier layer, meanwhile, the fluorine-containing polymer matrix provides chemical inertness and has a synergistic effect with the graphene, and the salt spray resistance time exceeds 2000 hours.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and in particular to a coating and a preparation method thereof. Background Art

[0002] With the rapid development of industrial technology, the demand for high-performance coatings is growing in aerospace, marine engineering, new energy and other fields. Traditional coatings have certain limitations in corrosion resistance and dispersion stability, making it difficult to meet the requirements of long-term use in complex environments.

[0003] Graphene, with its excellent mechanical properties, high specific surface area, and good chemical stability, has become a highly sought-after reinforcement material in the coatings industry. However, due to its high surface energy and strong van der Waals forces between its layers, graphene easily aggregates in coating systems, making it difficult to evenly disperse. This significantly limits its performance advantages and prevents the coating from fully realizing its reinforcing effects. Therefore, existing technologies require further development. Summary of the Invention

[0004] In view of the various deficiencies of the existing technology, in order to solve the above problems, a coating and a preparation method thereof are proposed, and the following technical solutions are provided: A coating, the raw materials of which include, by weight, 1-5 parts of graphene, 10-30 parts of fluorine-containing monomer, 2-8 parts of auxiliary agent, 30-60 parts of solvent, and 2-5 parts of curing agent.

[0005] Furthermore, the auxiliary agent has a structural formula of R1-O-(CF2)nO-R2, wherein R1 is an aromatic ring group, R2 is a fluorine-containing alkyl chain, and n=2-8.

[0006] Furthermore, the auxiliary agent has a structural formula of phenyl-O-(CF2)4-O-C3F7.

[0007] Furthermore, the fluorine-containing monomer is a fluorine-containing acrylate monomer.

[0008] Furthermore, the fluorine-containing acrylate monomer is selected from one or more of dodecafluoroheptyl methacrylate, hexafluorobutyl acrylate, and perfluorooctylethyl methacrylate.

[0009] Furthermore, the raw materials include, by weight, 3 parts of graphene, 20 parts of fluorine-containing monomer, 5 parts of auxiliary agent, 50 parts of solvent, and 3 parts of curing agent.

[0010] In addition, the present invention also provides a method for preparing the above-mentioned coating, comprising the following steps: adding graphene and an additive to a solvent for dispersion treatment, adding a fluorine-containing monomer, stirring, and then adding a curing agent to obtain the coating.

[0011] Furthermore, the graphene and the additive are added to the solvent and processed by a sand mill 2-3 times before adding the fluorine-containing monomer.

[0012] Furthermore, the sand mill treatment conditions are a pressure of 12-20 bar and a gap of 400-600 μm.

[0013] Furthermore, a fluorine-containing monomer is added and stirred for 1-2 hours, and then a curing agent is added. After adding the curing agent, stirring is continued for 10-20 minutes to obtain a coating.

[0014] Beneficial effects: 1. The additive of the present invention combines with graphene through the π-π bond of the aromatic ring structure, and at the same time, the fluorine-containing end copolymerizes with the fluorine-containing monomer to form a "bridging" effect, so that the graphene is evenly dispersed.

[0015] 2. The additive of the present invention effectively improves the dispersibility of graphene in the coating system, avoids the agglomeration of graphene, and enables it to be evenly dispersed in the coating to form a dense barrier layer. At the same time, the fluorine-containing polymer matrix provides chemical inertness and synergistically acts with graphene, with a salt spray resistance time of more than 2000 hours.

[0016] 3. The coating prepared by the present invention combines the high barrier properties of graphene and the excellent corrosion resistance of fluoropolymers. The formed coating is dense, has good chemical stability and low surface energy, can effectively prevent the invasion of corrosive media, and significantly improve the corrosion resistance of the coated material. DETAILED DESCRIPTION

[0017] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is clearly and completely described below in conjunction with the embodiments of the present invention. Based on the embodiments in this application, other similar embodiments obtained by ordinary technicians in this field without making any creative work should fall within the scope of protection of this application.

[0018] According to an embodiment of the present invention, a coating is provided, wherein the raw materials thereof include, by weight, 1-5 parts of graphene, 10-30 parts of fluorinated monomers, 2-8 parts of auxiliary agents, 30-60 parts of solvents, and 3-10 parts of curing agents. Specifically, the auxiliary agent structural formula is R1-O-(CF2)nO-R2, wherein R1 is an aromatic ring group, and R2 is a fluorinated alkyl chain, and n=2-8. On the one hand, the auxiliary agent of the present invention is combined with graphene by an aromatic ring structure through a π-π bond, and the fluorinated end is copolymerized with the fluorinated monomer to form a "bridging" effect, so that the graphene is evenly dispersed. The auxiliary agent of the present invention not only combines with the graphene π-π bond to prevent graphene from agglomerating, but also copolymerizes the fluorinated end with the fluorinated monomer to form a "bridging" effect, so that the graphene is evenly dispersed. In addition, the R1 and R2 of the auxiliary agent designed by the present application are hydrophobic groups, which significantly reduce the surface energy of the coating, and the prepared coating has good corrosion resistance and hydrophobic properties.

[0019] In the preparation process of coatings, the dosage ratio of each raw material is also very important. Controlling the dosage of additives, graphene and fluorine-containing monomers allows the graphene to be evenly dispersed in the coating to achieve the best anti-corrosion performance of the coating.

[0020] The thickness of the graphene sheets selected in the following examples is 2 nanometers.

[0021] Example 1 3 parts of graphene and 5 parts of the additive phenyl-O-(CF2)4-O-C3F7 were added to 50 parts of ethylene glycol butyl ether solvent to obtain a mixed solution. The mixed solution was sand milled twice, and then 20 parts of perfluorooctyl ethyl methacrylate was added. After stirring for 2 hours, 3 parts of BS-770 curing agent was added. After adding the curing agent, stirring was continued for 15 minutes to obtain a coating. The sand milling conditions were a pressure of 15 bar and a gap of 500 μm.

[0022] Example 2 5 parts of graphene and 8 parts of the additive phenyl-O-(CF2)4-O-C3F7 were added to 60 parts of ethylene glycol butyl ether solvent to obtain a mixed solution. The mixed solution was sand milled three times, and then 30 parts of dodecafluoroheptyl methacrylate were added. After stirring for 1.5 hours, 5 parts of BS-770 curing agent were added. After adding the curing agent, stirring was continued for 20 minutes to obtain a coating. The sand milling conditions were a pressure of 20 bar and a gap of 400 μm.

[0023] Example 3 One part of graphene and two parts of the additive phenyl-O-(CF2)4-O-C3F7 were added to 30 parts of ethylene glycol butyl ether solvent to prepare a mixture. The mixture was sand milled twice, and then 10 parts of dodecafluoroheptyl methacrylate were added. After stirring for one hour, two parts of BS-770 curing agent were added. After adding the curing agent, stirring was continued for 10 minutes to obtain a coating. The sand milling conditions were a pressure of 12 bar and a gap of 600 μm.

[0024] Comparative Example 1 3 parts of graphene were added to 50 parts of ethylene glycol butyl ether solvent to obtain a mixed solution. The mixed solution was sand milled twice, and then 20 parts of perfluorooctyl ethyl methacrylate were added. After stirring for 2 hours, 3 parts of BS-770 curing agent were added. After adding the curing agent, stirring was continued for 15 minutes to obtain a coating. The sand milling conditions were a pressure of 15 bar and a gap of 500 μm.

[0025] The difference between Comparative Example 1 and Example 1 is that no auxiliary agent is added.

[0026] Comparative Example 2 3 parts of graphene and 1 part of the additive phenyl-O-(CF2)4-O-C3F7 were added to 50 parts of ethylene glycol butyl ether solvent to obtain a mixed solution. The mixed solution was sand milled twice, and then 20 parts of perfluorooctyl ethyl methacrylate were added. After stirring for 2 hours, 3 parts of BS-770 curing agent were added. After adding the curing agent, stirring was continued for 15 minutes to obtain a coating. The sand milling conditions were a pressure of 15 bar and a gap of 500 μm.

[0027] Comparative Example 3 3 parts of graphene and 10 parts of the additive phenyl-O-(CF2)4-O-C3F7 were added to 50 parts of ethylene glycol butyl ether solvent to obtain a mixed solution. The mixed solution was sand milled twice, and then 20 parts of perfluorooctyl ethyl methacrylate was added. After stirring for 2 hours, 3 parts of BS-770 curing agent was added. After adding the curing agent, stirring was continued for 15 minutes to obtain a coating. The sand milling conditions were a pressure of 15 bar and a gap of 500 μm.

[0028] Comparative Example 4 3 parts of graphene and 5 parts of vinyl triethoxysilane were added to 50 parts of ethylene glycol butyl ether solvent to prepare a mixture. The mixture was sand milled twice, and then 20 parts of perfluorooctyl ethyl methacrylate was added. After stirring for 2 hours, 3 parts of BS-770 curing agent was added. After adding the curing agent, stirring was continued for 15 minutes to obtain a coating. The sand milling conditions were a pressure of 15 bar and a gap of 500 μm.

[0029] Comparative Example 5 3 parts of graphene and 5 parts of the additive phenyl-O-(CF2)4-O-C3F7 were added to 50 parts of ethylene glycol butyl ether solvent to obtain a mixed solution. The mixed solution was sand milled twice, and then 20 parts of methacrylate was added. After stirring for 2 hours, 3 parts of BS-770 curing agent was added. After adding the curing agent, stirring was continued for 15 minutes to obtain a coating. The sand milling conditions were a pressure of 15 bar and a gap of 500 μm.

[0030] Comparative Example 6 Ten parts of graphene and five parts of the additive phenyl-O-(CF2)4-O-C3F7 were added to 50 parts of ethylene glycol butyl ether solvent to prepare a mixture. The mixture was sand milled twice, and then 50 parts of perfluorooctylethyl methacrylate was added. After stirring for two hours, three parts of BS-770 curing agent were added. After adding the curing agent, stirring was continued for 15 minutes to obtain a coating. The sand milling conditions were a pressure of 15 bar and a gap of 500 μm.

[0031] Comparative Example 7 3 parts of graphene and 5 parts of auxiliary agent phenyl-O-(CF2)4-O-C3F7 were added to 50 parts of ethylene glycol butyl ether solvent to obtain a mixed solution, 20 parts of perfluorooctyl ethyl methacrylate were added, and after stirring for 2 hours, 3 parts of BS-770 curing agent were added. After adding the curing agent, stirring was continued for 15 minutes to obtain the coating.

[0032] The coatings of Examples 1-3 and Comparative Examples 1-7 were coated on metal plates respectively with a coating thickness of 50 μm. Dispersibility and salt spray resistance were tested according to national standards. The results are shown in Table 1.

[0033] Table 1 Dispersibility and salt spray resistance test results of Examples 1-3 and Comparative Examples 1-7 The coatings of Examples 1-3 and Comparative Examples 1-7 were respectively coated on metal plates with a coating thickness of 50 μm. Contact angle tests were performed according to national standards. The results are shown in Table 2.

[0034] Table 2 Contact angle test results of Examples 1-3 and Comparative Examples 1-7 As can be seen from Tables 1 and 2, the coating prepared in this application has good salt spray resistance and hydrophobic properties. The present invention improves the dispersibility of graphene in solution by adding an additive and combines the fluorinated monomer with the graphene material, thereby achieving both hydrophobicity and corrosion resistance. By comparing with the various comparative examples, it can be seen that the dosage ratio of each raw material and the selection of raw materials are also very important. Within a certain range, graphene and fluorinated monomers work together to improve corrosion resistance.

[0035] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A coating, characterized in that: The raw materials include, by weight, 1-5 parts of graphene, 10-30 parts of fluorine-containing monomer, 2-8 parts of auxiliary agent, 30-60 parts of solvent, and 2-5 parts of curing agent.

2. The coating according to claim 1, characterized in that The auxiliary agent has a structural formula of R1-O-(CF2)nO-R2, wherein R1 is an aromatic ring group, R2 is a fluorine-containing alkyl chain, and n=2-8.

3. The coating according to claim 1 or 2, characterized in that The auxiliary agent has a structural formula of phenyl-O-(CF2)4-O-C3F7.

4. The coating according to claim 1, characterized in that The fluorine-containing monomer is a fluorine-containing acrylate monomer.

5. The coating according to claim 4, characterized in that The fluorine-containing acrylate monomer is selected from one or more of dodecafluoroheptyl methacrylate, hexafluorobutyl acrylate, and perfluorooctylethyl methacrylate.

6. The coating according to claim 1, characterized in that The raw materials include, by weight, 3 parts of graphene, 20 parts of fluorine-containing monomer, 5 parts of auxiliary agent, 50 parts of solvent, and 3 parts of curing agent.

7. A method for preparing the coating according to claims 1-6, characterized in that: The following steps are involved: Graphene and an auxiliary agent are added to a solvent for dispersion treatment, a fluorine-containing monomer is added, the mixture is stirred, and a curing agent is added to obtain a coating.

8. The method for preparing the coating according to claim 1, wherein: Graphene and the additives are added to the solvent and processed by a sand mill for 2-3 times before adding the fluorine-containing monomer.

9. The method for preparing the coating according to claim 8, wherein: The sand mill treatment conditions are a pressure of 12-20 bar and a gap of 400-600 μm.

10. The method for preparing the coating according to claim 7, wherein: After adding the fluorine-containing monomer and stirring for 1-2 hours, the curing agent is added, and after adding the curing agent, the stirring is continued for 10-20 minutes to obtain the coating.

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