A kind of graphene conductive anti-corrosion coating and preparation method thereof

Abstract

The invention discloses a graphene conductive anti-corrosion coating and a preparation method thereof, and relates to the field of coatings, comprising the following raw materials by weight: 1-10 parts of graphene, 0.2-5 parts of carbon nanotubes, 20-70 parts of epoxy resin and 1-5 parts of conductive gel. The specific method is: firstly subjecting the graphene to high temperature expansion treatment, then dipping it into the conductive gel, adding carbon nanotubes, and finally adding epoxy resin, mixing evenly, and obtaining. By adding graphene, carbon nanotubes and conductive gel, the materials with different morphological structures form a rich three-dimensional conductive network structure, which greatly reduces the resistivity, improves the carrier mobility, and thus improves the anti-corrosion efficiency.

Description

Technical Field

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

[0002] Corrosion is one of the most common failure forms (wear and fracture) of metal materials. It not only wastes resources and damages the environment, but also causes many industrial accidents and poses a threat to human life and property. Although metal corrosion cannot be avoided, certain protection measures can be taken to slow down the rate of metal corrosion, thereby reducing the harm of corrosion. Surface organic coatings are one of the most commonly used and effective protection methods in metal protection technology because of their low cost and environmental friendliness. They use a layer of organic protective film to cover the metal surface to avoid direct contact between some corrosive media in the environment and the metal substrate, thereby reducing the chance of corrosion. However, during the protection process, organic coatings will be affected by salt spray, ultraviolet rays and some corrosive media, resulting in micropores or gaps, and corrosion channels, which will reduce the protective performance of the coating.

[0003] Graphene is an ideal two-dimensional crystal composed of a single layer of carbon atoms connected by covalent bonds. It has very high strength and hardness. The carrier mobility of graphene is very high and is almost unaffected by temperature. It also has very low resistivity.

[0004] However, graphene is not easy to disperse in organic coatings and is prone to agglomeration, which affects its performance. Summary of the invention

[0005] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art and to provide a graphene conductive anti-corrosion coating and a preparation method thereof.

[0006] The technical solution of the present invention is as follows:

[0007] A graphene conductive anti-corrosion coating comprises the following raw materials in parts by weight:

[0008] 1-10 parts of graphene, 0.2-5 parts of carbon nanotubes, 20-70 parts of epoxy resin and 1-5 parts of conductive gel.

[0009] As a preferred embodiment of the present invention, the conductive gel comprises a mixture of mica and lithium magnesium silicate in a mass ratio of 1:3-5.

[0010] The present invention also discloses a method for preparing a graphene conductive anti-corrosion coating, comprising the following steps:

[0011] The graphene is first subjected to high temperature expansion treatment, then impregnated into a conductive gel, carbon nanotubes are added, and finally epoxy resin is added and mixed evenly to obtain the product.

[0012] As a preferred embodiment of the present invention, the high temperature expansion treatment temperature is 550-700°C.

[0013] As a preferred embodiment of the present invention, the impregnation adopts an ultrasonic impregnation method.

[0014] As a preferred embodiment of the present invention, the preparation method of the conductive gel is as follows: mica and lithium magnesium silicate are dissolved in a citric acid solution and mixed evenly.

[0015] As a preferred embodiment of the present invention, a silane coupling agent is further added to the conductive gel.

[0016] As a preferred embodiment of the present invention, the added amount of the silane coupling agent is 1-5wt% of the conductive gel.

[0017] As a preferred embodiment of the present invention, 3-pyridyltriethoxysilane is further added to the conductive gel.

[0018] The beneficial effects of the present invention are:

[0019] The graphene conductive anti-corrosion coating of the present invention forms a rich three-dimensional conductive network structure by adding graphene, carbon nanotubes and conductive gel, which greatly reduces the resistivity and improves the carrier mobility, thereby improving the anti-corrosion efficiency. Furthermore, the added silane coupling agent can improve the dispersibility of graphene in epoxy resin and reduce the possibility of its agglomeration. In addition, the pyridine group in 3-pyridyltriethoxysilane can cooperate with metal ions to reduce the probability of corrosion. DETAILED DESCRIPTION

[0020] The technical solution of the present invention is further described below with reference to specific embodiments.

[0021] Example 1

[0022] A graphene conductive anti-corrosion coating comprises the following raw materials in parts by weight:

[0023] 1 part graphene, 0.3 parts carbon nanotubes, 70 parts epoxy resin and 1 part conductive gel.

[0024] The conductive gel includes a mixture of mica and lithium magnesium silicate in a mass ratio of 1:3.

[0025] The present invention also discloses a method for preparing a graphene conductive anti-corrosion coating, comprising the following steps:

[0026] The graphene is first subjected to high temperature expansion treatment, then impregnated into a conductive gel, carbon nanotubes are added, and finally epoxy resin is added and mixed evenly to obtain the product.

[0027] The high temperature expansion treatment temperature is 550° C. and the treatment time is 30 seconds.

[0028] The impregnation adopts an ultrasonic impregnation method.

[0029] The preparation method of the conductive gel is as follows: mica and lithium magnesium silicate are dissolved in a citric acid solution with a concentration of 1wt%, and the mixture is mixed evenly.

[0030] Silane coupling agent KH550 is also added into the conductive gel.

[0031] The added amount of the silane coupling agent is 3 wt % of the conductive gel.

[0032] The conductive gel is further added with 3-pyridyltriethoxysilane accounting for 1 wt % of the conductive gel.

[0033] Example 2

[0034] A graphene conductive anti-corrosion coating comprises the following raw materials in parts by weight:

[0035] 3 parts of graphene, 0.8 parts of carbon nanotubes, 65 parts of epoxy resin and 2 parts of conductive gel.

[0036] The conductive gel includes a mixture of mica and lithium magnesium silicate in a mass ratio of 1:4.

[0037] The present invention also discloses a method for preparing a graphene conductive anti-corrosion coating, comprising the following steps:

[0038] The graphene is first subjected to high temperature expansion treatment, then impregnated into a conductive gel, carbon nanotubes are added, and finally epoxy resin is added and mixed evenly to obtain the product.

[0039] The high temperature expansion treatment temperature is 600° C. and the treatment time is 30 seconds.

[0040] The impregnation adopts an ultrasonic impregnation method.

[0041] The preparation method of the conductive gel is as follows: mica and lithium magnesium silicate are dissolved in a 2wt% citric acid solution and mixed evenly.

[0042] Silane coupling agent KH550 is also added into the conductive gel.

[0043] The added amount of the silane coupling agent is 2 wt % of the conductive gel.

[0044] 3 wt % of 3-pyridyltriethoxysilane is also added into the conductive gel.

[0045] Example 3

[0046] A graphene conductive anti-corrosion coating comprises the following raw materials in parts by weight:

[0047] 5 parts of graphene, 1.1 parts of carbon nanotubes, 70 parts of epoxy resin and 3 parts of conductive gel.

[0048] The conductive gel includes a mixture of mica and lithium magnesium silicate in a mass ratio of 1:3.

[0049] The present invention also discloses a method for preparing a graphene conductive anti-corrosion coating, comprising the following steps:

[0050] The graphene is first subjected to high temperature expansion treatment, then impregnated into a conductive gel, carbon nanotubes are added, and finally epoxy resin is added and mixed evenly to obtain the product.

[0051] The high temperature expansion treatment temperature is 650° C. and the treatment time is 30 seconds.

[0052] The impregnation adopts an ultrasonic impregnation method.

[0053] The preparation method of the conductive gel is as follows: mica and lithium magnesium silicate are dissolved in a citric acid solution and mixed evenly.

[0054] Silane coupling agent KH550 is also added into the conductive gel.

[0055] The added amount of the silane coupling agent is 4 wt % of the conductive gel.

[0056] 5 wt % of 3-pyridyltriethoxysilane is also added into the conductive gel.

[0057] Example 4

[0058] A graphene conductive anti-corrosion coating comprises the following raw materials in parts by weight:

[0059] 6 parts of graphene, 1.5 parts of carbon nanotubes, 70 parts of epoxy resin and 5 parts of conductive gel.

[0060] The conductive gel includes a mixture of mica and lithium magnesium silicate in a mass ratio of 1:4.

[0061] The present invention also discloses a method for preparing a graphene conductive anti-corrosion coating, comprising the following steps:

[0062] The graphene is first subjected to high temperature expansion treatment, then impregnated into a conductive gel, carbon nanotubes are added, and finally epoxy resin is added and mixed evenly to obtain the product.

[0063] The high temperature expansion treatment temperature is 700° C. and the treatment time is 30 seconds.

[0064] The impregnation adopts an ultrasonic impregnation method.

[0065] The preparation method of the conductive gel is as follows: mica and lithium magnesium silicate are dissolved in a citric acid solution and mixed evenly.

[0066] Silane coupling agent KH550 is also added into the conductive gel.

[0067] The added amount of the silane coupling agent is 5 wt % of the conductive gel.

[0068] 5 wt % of 3-pyridyltriethoxysilane is also added into the conductive gel.

[0069] Example 5

[0070] A graphene conductive anti-corrosion coating comprises the following raw materials in parts by weight:

[0071] 10 parts graphene, 4 parts carbon nanotubes, 70 parts epoxy resin and 4 parts conductive gel.

[0072] The conductive gel includes a mixture of mica and lithium magnesium silicate in a mass ratio of 1:3.

[0073] The present invention also discloses a method for preparing a graphene conductive anti-corrosion coating, comprising the following steps:

[0074] The graphene is first subjected to high temperature expansion treatment, then impregnated into a conductive gel, carbon nanotubes are added, and finally epoxy resin is added and mixed evenly to obtain the product.

[0075] The high temperature expansion treatment temperature is 700° C. and the treatment time is 30 seconds.

[0076] The impregnation adopts an ultrasonic impregnation method.

[0077] The preparation method of the conductive gel is as follows: mica and lithium magnesium silicate are dissolved in a citric acid solution and mixed evenly.

[0078] Silane coupling agent KH550 is also added into the conductive gel.

[0079] The added amount of the silane coupling agent is 2 wt % of the conductive gel.

[0080] 1.5 wt % of 3-pyridyltriethoxysilane is also added into the conductive gel.

[0081] Comparative Example 1 (without carbon nanotubes)

[0082] A graphene conductive anti-corrosion coating comprises the following raw materials in parts by weight:

[0083] 10 parts graphene, 70 parts epoxy resin and 4 parts conductive gel.

[0084] The conductive gel includes a mixture of mica and lithium magnesium silicate in a mass ratio of 1:3.

[0085] The present invention also discloses a method for preparing a graphene conductive anti-corrosion coating, comprising the following steps:

[0086] The graphene is first subjected to high temperature expansion treatment, then impregnated into a conductive gel, and finally epoxy resin is added and mixed evenly to obtain the product.

[0087] The high temperature expansion treatment temperature is 700° C. and the treatment time is 30 seconds.

[0088] The impregnation adopts an ultrasonic impregnation method.

[0089] The preparation method of the conductive gel is as follows: mica and lithium magnesium silicate are dissolved in a citric acid solution and mixed evenly.

[0090] Silane coupling agent KH550 is also added into the conductive gel.

[0091] The added amount of the silane coupling agent is 2 wt % of the conductive gel.

[0092] 1.5 wt % of 3-pyridyltriethoxysilane is also added into the conductive gel.

[0093] Comparative Example 2 (without conductive gel)

[0094] A graphene conductive anti-corrosion coating comprises the following raw materials in parts by weight:

[0095] 10 parts of graphene, 4 parts of carbon nanotubes, and 70 parts of epoxy resin.

[0096] The present invention also discloses a method for preparing a graphene conductive anti-corrosion coating, comprising the following steps:

[0097] The graphene is first subjected to high temperature expansion treatment, carbon nanotubes are added, and finally epoxy resin is added and mixed evenly to obtain the product.

[0098] The high temperature expansion treatment temperature is 700° C. and the treatment time is 30 seconds.

[0099] The impregnation adopts an ultrasonic impregnation method.

[0100] Comparative Example 3 (without silane coupling agent)

[0101] A graphene conductive anti-corrosion coating comprises the following raw materials in parts by weight:

[0102] 10 parts graphene, 4 parts carbon nanotubes, 70 parts epoxy resin and 4 parts conductive gel.

[0103] The conductive gel includes a mixture of mica and lithium magnesium silicate in a mass ratio of 1:3.

[0104] The present invention also discloses a method for preparing a graphene conductive anti-corrosion coating, comprising the following steps:

[0105] The graphene is first subjected to high temperature expansion treatment, then impregnated into a conductive gel, carbon nanotubes are added, and finally epoxy resin is added and mixed evenly to obtain the product.

[0106] The high temperature expansion treatment temperature is 700° C. and the treatment time is 30 seconds.

[0107] The impregnation adopts an ultrasonic impregnation method.

[0108] The preparation method of the conductive gel is as follows: mica and lithium magnesium silicate are dissolved in a citric acid solution and mixed evenly.

[0109] 1.5 wt % of 3-pyridyltriethoxysilane is also added into the conductive gel.

[0110] Comparative Example 4 (without 3-pyridyltriethoxysilane)

[0111] A graphene conductive anti-corrosion coating comprises the following raw materials in parts by weight:

[0112] 10 parts graphene, 4 parts carbon nanotubes, 70 parts epoxy resin and 4 parts conductive gel.

[0113] The conductive gel includes a mixture of mica and lithium magnesium silicate in a mass ratio of 1:3.

[0114] The present invention also discloses a method for preparing a graphene conductive anti-corrosion coating, comprising the following steps:

[0115] The graphene is first subjected to high temperature expansion treatment, then impregnated into a conductive gel, carbon nanotubes are added, and finally epoxy resin is added and mixed evenly to obtain the product.

[0116] The high temperature expansion treatment temperature is 700° C. and the treatment time is 30 seconds.

[0117] The impregnation adopts an ultrasonic impregnation method.

[0118] The preparation method of the conductive gel is as follows: mica and lithium magnesium silicate are dissolved in a citric acid solution and mixed evenly.

[0119] A silane coupling agent is also added into the conductive gel.

[0120] The added amount of the silane coupling agent is 2 wt % of the conductive gel.

[0121] 1.5 wt % of 3-pyridyltriethoxysilane is also added into the conductive gel.

[0122] The above-mentioned embodiments and comparative examples are coated on metal surfaces to form coatings, and the coatings are tested for anti-corrosion performance. The test results are shown in the table.

[0123] (1) Test the contact resistance with carbon paper under 0.6Mpa pressure (mΩ.cm 2 );

[0124] (2) Test the contact resistance in a corrosive environment at a pressure of 0.6 MPa (A / cm) 2 .

[0125] Sample Contact resistance Contact resistance Example 1 4 <![CDATA[5.2×10 -6 ]]> Example 2 3 <![CDATA[5.7×10 -6 ]]> Example 3 5 <![CDATA[5.5×10 -6 ]]> Example 4 3 <![CDATA[5.4×10 -6 ]]> Example 5 4 <![CDATA[5.6×10 -6 ]]> Comparative Example 1 9 <![CDATA[9.5×10 -6 ]]> Comparative Example 2 10 <![CDATA[9.9×10 -6 ]]> Comparative Example 3 8 <![CDATA[9.1×10 -6 ]]> Comparative Example 4 8 <![CDATA[9×10 -6 ]]>

[0126] As can be seen from the above table, the performance of the embodiment is better than that of the comparative example. The main reasons may be as follows: by adding graphene, carbon nanotubes and conductive gel, the materials with different morphological structures form a rich three-dimensional conductive network structure, which greatly reduces the resistivity and improves the carrier mobility, thereby improving the anti-corrosion efficiency. Moreover, the added silane coupling agent can improve the dispersibility of graphene in epoxy resin and reduce the possibility of its agglomeration. In addition, the pyridine group in 3-pyridyltriethoxysilane can cooperate with metal ions to reduce the probability of corrosion.

[0127] Under the premise that no conflict occurs, those skilled in the art may freely combine and superimpose the above-mentioned additional technical features.

[0128] The above-mentioned embodiments only express the preferred implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, various other corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all these changes and deformations should fall within the scope of protection of the claims of the present invention.

Claims

1. A graphene conductive anti-corrosion coating, characterized in that: It includes the following raw materials in parts by weight: 1-10 parts of graphene, 0.2-5 parts of carbon nanotubes, 20-70 parts of epoxy resin and 1-5 parts of conductive gel; The conductive gel comprises a mixture of mica and lithium magnesium silicate in a mass ratio of 1:3-5; The preparation method of the conductive gel is as follows: mica and lithium magnesium silicate are dissolved in a citric acid solution and mixed evenly; A silane coupling agent is also added to the conductive gel; The amount of the silane coupling agent added is 1-5wt% of the conductive gel; 3-pyridyltriethoxysilane is also added into the conductive gel.

2. A method for preparing the graphene conductive anti-corrosion coating according to claim 1, characterized in that: The method comprises the following steps: firstly subjecting graphene to high temperature expansion treatment, then dipping it into conductive gel, adding carbon nanotubes, and finally adding epoxy resin, mixing them evenly to obtain the product.

3. The method for preparing a graphene conductive anti-corrosion coating according to claim 2, characterized in that: The high temperature expansion treatment temperature is 550-700°C.

4. The method for preparing a graphene conductive anti-corrosion coating according to claim 2, characterized in that: The impregnation adopts an ultrasonic impregnation method.