A non-covalently modified graphene anti-corrosion coating and preparation method thereof

Abstract

The present invention discloses a non-covalently modified graphene anti-corrosion coating and its preparation method, belonging to the technical field of anti-corrosion coatings. The non-covalently modified graphene anti-corrosion coating of the present invention comprises a base material, a curing agent, and a graphene dispersion in a mass ratio of 100:25:10. The graphene dispersion comprises the following components in parts by mass: 67-98.9 parts n-butanol, 0.1-3 parts graphene, 0.2-6 parts quinacridone, and 0.8-24 parts modified quinacridone. The base material comprises the following components in parts by mass: 92-99 parts epoxy resin, 0-6 parts n-butanol, and 1-2 parts light stabilizer. The curing agent comprises the following components in parts by mass: 90-100 parts aminosilane, 0-6 parts n-butanol, and 0-5 parts butyl acetate. The non-covalently modified graphene anti-corrosion coating of the present invention exhibits excellent corrosion and wear resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of anti-corrosion coatings, and in particular to a non-covalently modified graphene anti-corrosion coating and a preparation method thereof. Background Art

[0002] It's reported that technical losses caused by corrosion account for one-third of total metal production, far exceeding the combined losses from natural disasters like fires and earthquakes. Corrosion also poses a significant threat to production safety. For example, corrosion can easily cause bridges to break or collapse, leading to serious traffic accidents. Corrosion in aircraft can easily lead to malfunctions and even crashes.

[0003] Graphene is a two-dimensional carbon material with a single atomic layer thickness and a large specific surface area (2630m 2 / g), high Young's modulus (1TPa) and other excellent properties. Complete graphene has a complete shielding effect on corrosive factors such as water, oxygen and chloride ions, and adding it to an organic coating can improve the corrosion resistance of the coating. However, when using graphene oxide to prepare an anti-corrosion coating, there is a problem that the structure and performance of the graphene are greatly reduced, and the enhancement effect is not ideal. The use of non-oxidized graphene is likely to lead to poor dispersion of graphene, and there are problems such as poor interface bonding between graphene and the matrix resin and the clumping structure of graphene in the coating. Therefore, it is impossible to achieve the technical effect of adding graphene to an organic coating to significantly improve the corrosion resistance of the coating. Summary of the Invention

[0004] The purpose of the present invention is to provide a non-covalently modified graphene anti-corrosion coating and a preparation method thereof, so as to solve the problems existing in the above-mentioned prior art.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] One of the technical solutions of the present invention: a non-covalently modified graphene anti-corrosion coating, comprising a base material, a curing agent and a graphene dispersion in a mass ratio of 100:25:10;

[0007] The graphene dispersion comprises the following components in parts by mass: 67 to 98.9 parts of n-butanol, 0.1 to 3 parts of graphene, 0.2 to 6 parts of quinacridone, and 0.8 to 24 parts of modified quinacridone;

[0008] The modified quinacridone includes epoxy resin-modified quinacridone.

[0009] Furthermore, the base material comprises the following components in parts by mass: 92-99 parts of epoxy resin, 0-6 parts of n-butanol and 1-2 parts of light stabilizer;

[0010] The curing agent comprises the following components in parts by mass: 90-100 parts of aminosilane, 0-6 parts of n-butanol and 0-5 parts of butyl acetate.

[0011] Furthermore, the aminosilane includes 3-aminopropyltriethylsilane.

[0012] Furthermore, the method for preparing the graphene dispersion comprises the following steps:

[0013] Quinacridone and epoxy resin are added to n-butanol, and then a redox catalyst is added, and the mixture is heated for reaction (covalent grafting of quinacridone and epoxy resin) to obtain a modified quinacridone solution;

[0014] Graphene and quinacridone are added to the modified quinacridone solution and dispersed evenly to obtain the graphene dispersion.

[0015] Furthermore, the mass ratio of the quinacridone to the epoxy resin is 1:3; the redox catalyst includes di-n-octyltin dilaurate; the heating reaction is carried out at a rotation speed of 500-700 r / min; the heating reaction temperature is 40-60° C., and the time is 1-2 hours.

[0016] Further, the dispersing includes ultrasonic dispersing;

[0017] The power of the ultrasonic dispersion is 300-600W, and the time is 15-40 minutes.

[0018] The second technical solution of the present invention is a method for preparing the above-mentioned non-covalently modified graphene anti-corrosion coating, comprising the following steps:

[0019] A base material is added to the graphene dispersion, and the mixture is stirred evenly, followed by adding a curing agent and stirring evenly to obtain the non-covalently modified graphene anti-corrosion coating.

[0020] Furthermore, the stirring speed is 500-600 r / min.

[0021] Graphene is a two-dimensional carbon material with a single atomic layer thickness and a large specific surface area (2630m 2 / g), and high Young's modulus (1TPa), among other excellent properties. Complete graphene has a complete shielding effect against corrosive factors such as water, oxygen, and chloride ions. Adding it to an organic coating can significantly improve the coating's corrosion resistance. Furthermore, graphene has a simple, repetitive molecular structure and exceptional chemical inertness, thus also improving the stability of organic coatings against corrosive environments. However, due to its large specific surface area and the effects of van der Waals forces, graphene has poor dispersibility in polymers. When added to organic coatings, it easily forms aggregates and defects, resulting in a coating with poor shielding effect against corrosive factors.

[0022] The modified quinacridone (obtained by forming a covalent bond between quinacridone and epoxy resin) used in the present invention can form π-π and CH-π non-covalent bonds with unmodified quinacridone and graphene, thereby strengthening the connection between the graphene and the matrix resin, improving the interfacial bonding strength between the graphene and the matrix resin, achieving high dispersibility of the graphene, and enabling the epoxy coating to obtain excellent anti-corrosion performance.

[0023] The third technical solution of the present invention: an application of the above-mentioned non-covalently modified graphene anti-corrosion coating in the corrosion protection of metal materials.

[0024] Furthermore, the application method specifically includes: coating the non-covalently modified graphene anti-corrosion coating on the surface of a metal material, and obtaining a metal material with a coating after curing;

[0025] The thickness of the coating is 20 to 80 μm.

[0026] Furthermore, the coating method includes brushing or spraying.

[0027] The present invention discloses the following technical effects:

[0028] (1) The non-covalently modified graphene anti-corrosion coating of the present invention has good anti-corrosion and wear resistance, can be fully dried within 48 hours, and can be applied to the metal surface. The coating can effectively prevent the metal from being corroded by the environment; and the present invention achieves a significant improvement in anti-corrosion performance with a very small amount of graphene.

[0029] (2) The non-covalently modified graphene anti-corrosion coating of the present invention is composed of a base material, a curing agent, and a graphene dispersion. The modified quinacridone (obtained by forming a covalent bond between quinacridone and epoxy resin) used in the present invention can form π-π and CH-π non-covalent bonds with the unmodified quinacridone and graphene, thereby strengthening the connection between the graphene and the matrix resin, improving the interfacial bonding strength between the graphene and the matrix resin, and achieving excellent dispersion of the graphene. The integrity of the graphene structure and performance is retained, thereby improving the performance of the epoxy coating in resisting corrosion factors and mechanical wear. DETAILED DESCRIPTION

[0030] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0031] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between any intermediate value within a stated value or stated range and any other stated value or intermediate value within the stated range is also encompassed by the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0032] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0033] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the present invention. The present description and examples are intended to be illustrative only.

[0034] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0035] All “parts” described in the following examples are “parts by mass”.

[0036] The graphene dispersion, base material and curing agent of the present invention can be prepared separately and can be stored for a long time after preparation. Before use, the components are mixed and stirred evenly to obtain a coating solution. The effective use time of the coating solution after preparation is no more than 6 hours.

[0037] (1) A method for preparing a graphene dispersion, comprising the following steps:

[0038] 0.2-6 parts of quinacridone and 6-18 parts of epoxy resin are added to 67-98.9 parts of n-butanol, and the mass ratio of quinacridone to epoxy resin is controlled to be 1:3. Then, a redox catalyst is added (the amount of the redox catalyst is 1-3% of the mass of the graphene dispersion formula, di-n-octyltin dilaurate), and heated to react (rotation speed of 500-700 r / min, temperature of 40-60° C., and time of 1-2 hours) to obtain a modified quinacridone solution;

[0039] 0.1 to 3 parts of graphene and 0.2 to 6 parts of quinacridone are added to the modified quinacridone solution, and ultrasonic dispersion is performed uniformly (the power of ultrasonic dispersion is 300 to 600 W, and the time is 15 to 40 minutes) to obtain a graphene dispersion liquid.

[0040] (2) A method for preparing a curing agent comprises the following steps: 90 to 100 parts of aminosilane, 0 to 6 parts of n-butanol, and 0 to 5 parts of butyl acetate are stirred uniformly at a speed of 500 to 600 r / min at room temperature for 5 minutes to obtain a curing agent.

[0041] (3) A method for preparing a base material, comprising the following steps: uniformly stirring 92 to 99 parts of epoxy resin, 0 to 6 parts of n-butanol, and 1 to 2 parts of a light stabilizer at room temperature at a speed of 500 to 600 r / min (10 minutes) to obtain a base material.

[0042] Example 1

[0043] A method for preparing a non-covalently modified graphene anti-corrosion coating:

[0044] Base material formula (100kg): epoxy resin 92kg, n-butanol 6kg, light stabilizer (light stabilizer tinuvin1130) 2kg.

[0045] Curing agent formula (25kg): 22.5kg of 3-aminopropyltriethylsilane, 1.25kg of n-butanol, and 1.25kg of butyl acetate.

[0046] Graphene dispersion formula (10kg): 7.8kg of n-butanol, 0.2kg of graphene, 0.4kg of quinacridone (unmodified), and 1.6kg of modified quinacridone.

[0047] Preparation method:

[0048] (1) 0.4 kg of quinacridone, 7.8 kg of n-butanol, 1.2 kg of epoxy resin, and a trace amount of redox catalyst (the amount of redox catalyst is 1% of the mass of the graphene dispersion formula, dioctyltin dilaurate) are added to a reaction vessel in sequence, and stirred at 60°C and 500 r / min for 1 hour to obtain a solution containing 1.6 kg of modified quinacridone. 0.4 kg of quinacridone and 0.2 kg of graphene are then added to the above solution, and the solution is treated with an ultrasonic processor at a power of 300 W for 40 minutes to obtain a graphene dispersion.

[0049] (2) 92 kg of epoxy resin, 6 kg of n-butanol, and 2 kg of light stabilizer were added to the above-mentioned graphene dispersion in sequence, and the mixture was stirred at a speed of 500 r / min at room temperature for 30 min. Then, 22.5 kg of 3-aminopropyltriethylsilane, 1.25 kg of n-butanol, and 1.25 kg of butyl acetate were added in sequence, and the mixture was stirred at a speed of 500 r / min at room temperature for 30 min to obtain a non-covalently modified graphene anti-corrosion coating (a new type of non-covalently modified graphene anti-corrosion coating).

[0050] The graphene content in the non-covalently modified graphene anti-corrosion coating prepared in this example is about 0.15 wt.%.

[0051] Within 6 hours after the base material and the curing agent are mixed, the coating is applied to the surface of the metal substrate by brushing, spraying, etc., and cured at room temperature to obtain a metal material with an anti-corrosion coating (thickness of about 30 to 50 μm).

[0052] Example 2

[0053] A method for preparing a non-covalently modified graphene anti-corrosion coating:

[0054] Base material formula (100kg): epoxy resin 99kg, light stabilizer (light stabilizer tinuvin 1130) 1kg.

[0055] Curing agent formula (25kg): 24.5kg of 3-aminopropyltriethylsilane and 0.5kg of butyl acetate.

[0056] Graphene dispersion formula (10kg): 8.9kg of n-butanol, 0.1kg of graphene, 0.2kg of quinacridone (unmodified), and 0.8kg of modified quinacridone.

[0057] Preparation method:

[0058] (1) 0.2 kg of quinacridone, 8.9 kg of n-butanol, 0.6 kg of epoxy resin, and a trace amount of redox catalyst (the amount of redox catalyst is 1% of the mass of the graphene dispersion formula, dioctyltin dilaurate) are added to a reaction vessel in sequence, and stirred at 60°C and 500 r / min for 1 hour to obtain a solution containing 0.8 kg of modified quinacridone. 0.2 kg of quinacridone and 0.1 kg of graphene are then added to the above solution, and the solution is treated with an ultrasonic processor at a power of 500 W for 30 minutes to obtain a graphene dispersion.

[0059] (2) 99 kg of epoxy resin and 1 kg of light stabilizer were added to the above-mentioned graphene dispersion in sequence, and the mixture was stirred at a speed of 600 r / min at room temperature for 30 min. Then, 24.5 kg of 3-aminopropyltriethoxysilane and 0.5 kg of butyl acetate were added in sequence, and the mixture was stirred at a speed of 600 r / min at room temperature for 30 min to obtain a non-covalently modified graphene anti-corrosion coating (a new type of non-covalently modified graphene anti-corrosion coating).

[0060] The graphene content in the non-covalently modified graphene anti-corrosion coating prepared in this example is about 0.07 wt.%.

[0061] Within 6 hours after the base material and the curing agent are mixed, the coating is applied to the surface of the metal substrate by brushing, spraying, etc., and cured at room temperature to obtain a metal material with an anti-corrosion coating (thickness of about 30 to 50 μm).

[0062] Example 3

[0063] A method for preparing a non-covalently modified graphene anti-corrosion coating:

[0064] Base material formula (100kg): 93kg epoxy resin, 6kg n-butanol, 1kg light stabilizer (light stabilizer tinuvin1130).

[0065] Curing agent formula (25kg): 23kg of 3-aminopropyltriethylsilane, 1.5kg of n-butanol, and 0.5kg of butyl acetate.

[0066] Graphene dispersion formula (10kg): 8.8kg of n-butanol, 0.2kg of graphene, 0.5kg of quinacridone (unmodified), and 0.5kg of modified quinacridone.

[0067] Preparation method:

[0068] (1) 0.125 kg of quinacridone, 8.8 kg of n-butanol, 0.375 kg of epoxy resin, and a trace amount of redox catalyst (the amount of redox catalyst is 1% of the mass of the graphene dispersion formula, dioctyltin dilaurate) are added to a reaction vessel in sequence, and stirred at 700 r / min at 50°C for 1 hour to obtain a solution containing 0.5 kg of modified quinacridone. 0.5 kg of quinacridone and 0.2 kg of graphene are then added to the above solution, and the solution is treated with an ultrasonic processor at a power of 600 W for 40 minutes to obtain a graphene dispersion.

[0069] (2) 93 kg of epoxy resin, 6 kg of n-butanol, and 1 kg of light stabilizer were added to the above-mentioned graphene dispersion in sequence, and the mixture was stirred at a speed of 600 r / min at room temperature for 30 min. Then, 23 kg of 3-aminopropyltriethoxysilane, 1.5 kg of n-butanol, and 0.5 kg of butyl acetate were added in sequence, and the mixture was stirred at a speed of 600 r / min at room temperature for 30 min to obtain a non-covalently modified graphene anti-corrosion coating (a new type of non-covalently modified graphene anti-corrosion coating).

[0070] The graphene content in the non-covalently modified graphene anti-corrosion coating prepared in this example is about 0.15 wt.%.

[0071] Within 6 hours after the base material and the curing agent are mixed, the coating is applied to the surface of the metal substrate by brushing, spraying, etc., and cured at room temperature to obtain a metal material with an anti-corrosion coating (thickness of about 50 to 80 μm).

[0072] The mechanical properties of the anti-corrosion coatings prepared using the non-covalently modified graphene anti-corrosion coatings prepared in Examples 1 to 3 of the present invention are shown in Table 1.

[0073] Table 1 Mechanical properties of the anti-corrosion coating of Example 1

[0074]

[0075]

[0076] Mechanical properties of the anti-corrosion coating of Example 2

[0077]

[0078]

[0079] Mechanical properties of the anti-corrosion coating of Example 3

[0080]

[0081] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A non-covalently modified graphene anti-corrosion coating, characterized in that: The components include a base material, a curing agent, and a graphene dispersion in a mass ratio of 100:25:10; The graphene dispersion comprises the following components in parts by mass: 67 to 98.9 parts of n-butanol, 0.1 to 3 parts of graphene, 0.2 to 6 parts of quinacridone, and 0.8 to 24 parts of modified quinacridone; The modified quinacridone includes epoxy resin modified quinacridone; The method for preparing the graphene dispersion comprises the following steps: Quinacridone and epoxy resin are added to n-butanol, and then a redox catalyst is added and heated to react to obtain a modified quinacridone solution; Graphene and quinacridone are added to the modified quinacridone solution and dispersed evenly to obtain the graphene dispersion.

2. The non-covalently modified graphene anti-corrosion coating according to claim 1, characterized in that The base material comprises the following components in parts by mass: 92-99 parts of epoxy resin, 0-6 parts of n-butanol and 1-2 parts of light stabilizer; The curing agent comprises the following components in parts by mass: 90-100 parts of aminosilane, 0-6 parts of n-butanol and 0-5 parts of butyl acetate.

3. The non-covalently modified graphene anti-corrosion coating according to claim 2, characterized in that: The aminosilane includes 3-aminopropyltriethylsilane.

4. The non-covalently modified graphene anti-corrosion coating according to claim 1, characterized in that: When preparing a graphene dispersion, the mass ratio of the quinacridone to the epoxy resin is 1:3; the redox catalyst includes di-n-octyltin dilaurate; the heating reaction is carried out at a rotation speed of 500 to 700 r / min; the heating reaction temperature is 40 to 60° C., and the time is 1 to 2 hours.

5. The non-covalently modified graphene anti-corrosion coating according to claim 1, characterized in that: When preparing the graphene dispersion: the dispersion includes ultrasonic dispersion; The power of the ultrasonic dispersion is 300-600W, and the time is 15-40 minutes.

6. A method for preparing the non-covalently modified graphene anti-corrosion coating according to any one of claims 1 to 5, characterized in that: The following steps are involved: A base material is added to the graphene dispersion, and the mixture is stirred evenly, followed by adding a curing agent and stirring evenly to obtain the non-covalently modified graphene anti-corrosion coating.

7. The preparation method according to claim 6, characterized in that The stirring speed is 500-600 r / min.

8. Use of the non-covalently modified graphene anti-corrosion coating according to any one of claims 1 to 5 in the anti-corrosion of metal materials.

9. The use according to claim 8, characterized in that The application method specifically comprises: coating the non-covalently modified graphene anti-corrosion coating on the surface of a metal material, and obtaining a metal material having a coating after curing; The thickness of the coating is 20 to 80 μm.

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