Surface protective coating of high-strength corrosion-resistant PTC (Positive Temperature Coefficient) electric heater and preparation method of surface protective coating

Abstract

The invention discloses a surface protective coating of a high-strength corrosion-resistant PTC (Positive Temperature Coefficient) electric heater and a preparation method. The surface protective coating comprises the following components in parts by mass: 10-20 parts of graphene powder; 5 to 15 parts of carbon nano tube powder; 30 to 50 parts of inorganic resin; 5 to 15 parts of aluminum oxide; 2-8 parts of boron nitride; 0.5-2 parts of a dispersant; 0.5 to 2 parts of a silane coupling agent; 10 to 20 parts of a diluent; the graphene powder, the carbon nanotubes and the boron nitride in the coating form a compact protective layer, so that water vapor erosion is effectively prevented, the corrosion resistance is improved, and the high-strength corrosion resistance is realized; the graphene powder, the carbon nanotubes and the aluminum oxide in the coating have excellent heat conduction performance, so that the coating has an efficient heat dissipation function, the heating power and the heat dissipation efficiency of the PTC electric heater are improved, and efficient heat conduction is achieved; after being cured, the coating has strong binding force with the surface of the PTC electric heater, is not easy to fall off, does not generate substances harmful to human bodies in the use process, and is green and environment-friendly.

Description

Technical Field

[0001] The invention belongs to the technical field of PTC electric heaters, and in particular relates to a surface protective coating of a high-strength corrosion-resistant PTC electric heater and a preparation method thereof. Background Art

[0002] PTC electric heaters have the characteristics of constant temperature heating, high heat conversion rate, high voltage resistance, small residual current, low power consumption, complete flame retardancy, fast response time, and long service life. However, in high humidity environments, the aluminum heat dissipation strips of PTC electric heaters easily absorb and accumulate water vapor, leading to oxidative corrosion, affecting heat dissipation performance and service life. At present, the anti-corrosion coatings on the market have problems such as poor thermal conductivity and complex manufacturing. Therefore, it is of great significance to develop a surface protective coating with high strength, corrosion resistance and good thermal conductivity.

[0003] Based on this, a surface protective coating and preparation method of a high-strength corrosion-resistant PTC electric heater are designed. Summary of the invention

[0004] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a surface protective coating and a preparation method of a high-strength corrosion-resistant PTC electric heater, which effectively solves the problems raised in the above background.

[0005] To achieve the above object, the present invention provides the following technical solution: a surface protective coating of a high-strength corrosion-resistant PTC electric heater comprises the following components in parts by mass:

[0006] Graphene powder: 10-20 parts;

[0007] Carbon nanotube powder: 5-15 parts;

[0008] Inorganic resin: 30-50 parts;

[0009] Alumina: 5-15 parts;

[0010] Boron nitride: 2-8 parts;

[0011] Dispersant: 0.5-2 parts;

[0012] Silane coupling agent: 0.5-2 parts;

[0013] Diluent: 10-20 parts.

[0014] Preferably, the inorganic resin is one of a silicate resin or an aluminate resin.

[0015] Preferably, the dispersant is one of polyethylene glycol or sodium lauryl sulfate.

[0016] Preferably, the silane coupling agent is one of KH550 and KH560.

[0017] Preferably, the diluent is one of ethanol or acetone.

[0018] A method for preparing a surface protective coating of a high-strength corrosion-resistant PTC electric heater comprises the following steps:

[0019] S1, Material preparation:

[0020] Weigh each component material according to the above mass fraction and set aside;

[0021] S2, Mixing and Dispersion:

[0022] Add graphene powder, carbon nanotube powder, aluminum oxide, boron nitride, dispersant, and silane coupling agent to a high-speed disperser for dispersion at a speed of 2000-3000 r / min and a dispersion time of 30-60 min until the raw materials are evenly dispersed;

[0023] S3, grinding treatment:

[0024] The mixture obtained in S2 is ground using a grinder, using grinding beads with a diameter of 0.5-1.5 mm, until the fineness reaches less than 20 microns to obtain a coating slurry;

[0025] S4, resin mixing:

[0026] Add the inorganic resin and the diluent to the coating slurry obtained in S3, and stir with a stirrer at a speed of 1000-1500 r / min for 30-50 min to ensure that the resin is evenly dispersed in the coating slurry;

[0027] S5, spray treatment:

[0028] Use a spraying device to evenly spray the coating obtained in S4 on the surface of the PTC electric heater, with a spraying thickness of 0.1-0.3 mm;

[0029] S6, curing treatment:

[0030] Place the sprayed PTC electric heater in an oven and bake it at 150-200°C for 2-4 hours to solidify the coating and form a dense protective layer.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. The graphene powder, carbon nanotubes and boron nitride in the coating of the present invention form a dense protective layer, which effectively prevents water vapor erosion and improves corrosion resistance, thereby achieving high-strength corrosion resistance;

[0033] 2. The excellent thermal conductivity of graphene powder, carbon nanotubes and alumina in the coating of the present invention enables the coating to have a high-efficiency heat dissipation function, thereby improving the heating power and heat dissipation efficiency of the PTC electric heater, thereby achieving high-efficiency heat conduction;

[0034] 3. The coating preparation method of the present invention is simple, does not require complicated processes and long-term curing, and reduces production costs;

[0035] 4. After the coating of the present invention is cured, it has a strong bonding force with the surface of the PTC electric heater and is not easy to fall off. In addition, it does not produce any substances harmful to the human body during use, and is green and environmentally friendly. DETAILED DESCRIPTION

[0036] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0037] The present invention provides a surface protective coating for a high-strength corrosion-resistant PTC electric heater, comprising the following components in parts by mass:

[0038] Graphene powder: 10-20 parts. Graphene powder has high thermal conductivity and good thermal radiation performance, which can effectively improve the thermal conductivity of the coating;

[0039] Carbon nanotube powder: 5-15 parts. Carbon nanotubes have excellent electrical and thermal conductivity and can form a thermal conductive network to improve the overall thermal conductivity of the coating.

[0040] Inorganic resin: 30-50 parts. Inorganic resin, as a binder, has good high temperature resistance and chemical stability, which can ensure the stability of the coating in high temperature environment;

[0041] Alumina: 5-15 parts. Alumina, as a thermal conductive filler, can improve the thermal conductivity of the coating, while increasing the hardness and wear resistance of the coating;

[0042] Boron nitride: 2-8 parts, enhances corrosion resistance, improves hardness and wear resistance, and can improve thermal conductivity;

[0043] Dispersant: 0.5-2 parts. Dispersant helps to evenly disperse graphene powder and carbon nanotubes in the resin and improve the overall performance of the coating.

[0044] Silane coupling agent: 0.5-2 parts. Silane coupling agent can improve the adhesion between the coating and the surface of the PTC electric heater and enhance the durability of the coating;

[0045] Thinner: 10-20 parts. Thinner is used to adjust the viscosity of the paint to facilitate spraying and curing.

[0046] The inorganic resin in this embodiment is one of silicate resin and aluminate resin.

[0047] The dispersant in this embodiment is one of polyethylene glycol or sodium lauryl sulfate.

[0048] The silane coupling agent in this embodiment is one of KH550 and KH560.

[0049] The diluent in this embodiment is one of ethanol or acetone.

[0050] A method for preparing a surface protective coating of a high-strength corrosion-resistant PTC electric heater comprises the following steps:

[0051] S1, Material preparation:

[0052] Weigh each component material according to the above mass fraction and set aside;

[0053] S2, Mixing and Dispersion:

[0054] Add graphene powder, carbon nanotube powder, aluminum oxide, boron nitride, dispersant, and silane coupling agent to a high-speed disperser for dispersion at a speed of 2000-3000 r / min and a dispersion time of 30-60 min until the raw materials are evenly dispersed;

[0055] S3, grinding treatment:

[0056] The mixture obtained in S2 is ground using a grinder, using grinding beads with a diameter of 0.5-1.5 mm, until the fineness reaches less than 20 microns to obtain a coating slurry;

[0057] S4, resin mixing:

[0058] Add the inorganic resin and the diluent to the coating slurry obtained in S3, and stir with a stirrer at a speed of 1000-1500 r / min for 30-50 min to ensure that the resin is evenly dispersed in the coating slurry;

[0059] S5, spray treatment:

[0060] Use a spraying device to evenly spray the coating obtained in S4 on the surface of the PTC electric heater, with a spraying thickness of 0.1-0.3 mm;

[0061] S6, curing treatment:

[0062] Place the sprayed PTC electric heater in an oven and bake it at 150-200°C for 2-4 hours to solidify the coating and form a dense protective layer.

[0063] Embodiment 1:

[0064] The surface protective coating of the high-strength anti-corrosion PTC electric heater includes the following components in parts by weight:

[0065] Graphene powder: 10 parts;

[0066] Carbon nanotube powder: 5 parts;

[0067] Inorganic resin: 30 parts;

[0068] Alumina: 5 parts;

[0069] Boron nitride: 2 parts;

[0070] Dispersant: 0.5 parts;

[0071] Silane coupling agent: 0.5 parts;

[0072] Diluent: 10 parts.

[0073] The inorganic resin in this embodiment is one of silicate resin and aluminate resin.

[0074] The dispersant in this embodiment is one of polyethylene glycol or sodium lauryl sulfate.

[0075] The silane coupling agent in this embodiment is one of KH550 and KH560.

[0076] The diluent in this embodiment is one of ethanol or acetone.

[0077] A method for preparing a surface protective coating of a high-strength corrosion-resistant PTC electric heater comprises the following steps:

[0078] S1, Material preparation:

[0079] Weigh each component material according to the above mass fraction and set aside;

[0080] S2, Mixing and Dispersion:

[0081] Add graphene powder, carbon nanotube powder, aluminum oxide, boron nitride, dispersant, and silane coupling agent into a high-speed disperser for dispersion at a speed of 2000 r / min for 30 min until the raw materials are evenly dispersed;

[0082] S3, grinding treatment:

[0083] The mixture obtained in S2 is ground using a grinder, using grinding beads with a diameter of 0.5 mm, until the fineness reaches less than 20 microns to obtain a coating slurry;

[0084] S4, resin mixing:

[0085] Add the inorganic resin and the diluent to the coating slurry obtained in S3, and stir the mixture for 30 minutes at a speed of 1000 r / min using a stirrer to ensure that the resin is evenly dispersed in the coating slurry;

[0086] S5, spray treatment:

[0087] Use a spraying device to evenly spray the coating obtained in S4 on the surface of the PTC electric heater with a spraying thickness of 0.1 mm;

[0088] S6, curing treatment:

[0089] The sprayed PTC electric heater was placed in an oven and baked at 150°C for 2 hours to solidify the coating and form a dense protective layer.

[0090] Embodiment 2:

[0091] The surface protective coating of the high-strength anti-corrosion PTC electric heater includes the following components in parts by weight:

[0092] Graphene powder: 20 parts;

[0093] Carbon nanotube powder: 15 parts;

[0094] Inorganic resin: 50 parts;

[0095] Alumina: 15 parts;

[0096] Boron nitride: 8 parts;

[0097] Dispersant: 2 parts;

[0098] Silane coupling agent: 2 parts;

[0099] Diluent: 20 parts.

[0100] The inorganic resin in this embodiment is one of silicate resin and aluminate resin.

[0101] The dispersant in this embodiment is one of polyethylene glycol or sodium lauryl sulfate.

[0102] The silane coupling agent in this embodiment is one of KH550 and KH560.

[0103] The diluent in this embodiment is one of ethanol or acetone.

[0104] A method for preparing a surface protective coating of a high-strength corrosion-resistant PTC electric heater comprises the following steps:

[0105] S1, Material preparation:

[0106] Weigh each component material according to the above mass fraction and set aside;

[0107] S2, Mixing and Dispersion:

[0108] Add graphene powder, carbon nanotube powder, aluminum oxide, boron nitride, dispersant, and silane coupling agent into a high-speed disperser for dispersion at a speed of 3000 r / min for 60 min until the raw materials are evenly dispersed;

[0109] S3, grinding treatment:

[0110] The mixture obtained in S2 is ground using a grinder, using grinding beads with a diameter of 1.5 mm, until the fineness reaches less than 20 microns, to obtain a coating slurry;

[0111] S4, resin mixing:

[0112] Add the inorganic resin and the diluent to the coating slurry obtained in S3, and stir the mixture for 50 min at a speed of 1500 r / min using a stirrer to ensure that the resin is evenly dispersed in the coating slurry;

[0113] S5, spray treatment:

[0114] Use a spraying device to evenly spray the coating obtained in S4 on the surface of the PTC electric heater, with a spraying thickness of 0.3 mm;

[0115] S6, curing treatment:

[0116] The sprayed PTC electric heater was placed in an oven and baked at 200°C for 4 hours to solidify the coating and form a dense protective layer.

[0117] Embodiment 3:

[0118] The surface protective coating of the high-strength anti-corrosion PTC electric heater includes the following components in parts by weight:

[0119] Graphene powder: 15 parts;

[0120] Carbon nanotube powder: 10 parts;

[0121] Inorganic resin: 40 parts;

[0122] Alumina: 10 parts;

[0123] Boron nitride: 5 parts;

[0124] Dispersant: 1.3 parts;

[0125] Silane coupling agent: 1.3 parts;

[0126] Diluent: 15 parts.

[0127] The inorganic resin in this embodiment is one of silicate resin and aluminate resin.

[0128] The dispersant in this embodiment is one of polyethylene glycol or sodium lauryl sulfate.

[0129] The silane coupling agent in this embodiment is one of KH550 and KH560.

[0130] The diluent in this embodiment is one of ethanol or acetone.

[0131] A method for preparing a surface protective coating of a high-strength corrosion-resistant PTC electric heater comprises the following steps:

[0132] S1, Material preparation:

[0133] Weigh each component material according to the above mass fraction and set aside;

[0134] S2, Mixing and Dispersion:

[0135] Add graphene powder, carbon nanotube powder, alumina, boron nitride, dispersant and silane coupling agent into a high-speed disperser for dispersion at a speed of 2500 r / min for 45 min until the raw materials are evenly dispersed;

[0136] S3, grinding treatment:

[0137] The mixture obtained in S2 is ground using a grinder, using grinding beads with a diameter of 1 mm, until the fineness reaches less than 20 microns, to obtain a coating slurry;

[0138] S4, resin mixing:

[0139] Add the inorganic resin and the diluent to the coating slurry obtained in S3, and stir with a stirrer at a speed of 1250 r / min for 45 min to ensure that the resin is evenly dispersed in the coating slurry;

[0140] S5, spray treatment:

[0141] Use a spraying device to evenly spray the coating obtained in S4 on the surface of the PTC electric heater, with a spraying thickness of 0.2 mm;

[0142] S6, curing treatment:

[0143] The sprayed PTC electric heater was placed in an oven and baked at 175°C for 3 hours to solidify the coating and form a dense protective layer.

[0144] Embodiment 4:

[0145] The surface protective coating of the high-strength anti-corrosion PTC electric heater includes the following components in parts by weight:

[0146] Graphene powder: 13 parts;

[0147] Carbon nanotube powder: 8 parts;

[0148] Inorganic resin: 35 parts;

[0149] Alumina: 8 parts;

[0150] Boron nitride: 4 parts;

[0151] Dispersant: 1 part;

[0152] Silane coupling agent: 1 part;

[0153] Diluent: 13 parts.

[0154] The inorganic resin in this embodiment is one of silicate resin and aluminate resin.

[0155] The dispersant in this embodiment is one of polyethylene glycol or sodium lauryl sulfate.

[0156] The silane coupling agent in this embodiment is one of KH550 and KH560.

[0157] The diluent in this embodiment is one of ethanol or acetone.

[0158] A method for preparing a surface protective coating of a high-strength corrosion-resistant PTC electric heater comprises the following steps:

[0159] S1, Material preparation:

[0160] Weigh each component material according to the above mass fraction and set aside;

[0161] S2, Mixing and Dispersion:

[0162] Add graphene powder, carbon nanotube powder, alumina, boron nitride, dispersant and silane coupling agent into a high-speed disperser for dispersion at a speed of 2300 r / min for 40 min until the raw materials are evenly dispersed;

[0163] S3, grinding treatment:

[0164] The mixture obtained in S2 is ground using a grinder, using grinding beads with a diameter of 0.8 mm, until the fineness reaches less than 20 microns, to obtain a coating slurry;

[0165] S4, resin mixing:

[0166] Add the inorganic resin and the diluent to the coating slurry obtained in S3, and stir the mixture for 35 minutes at a speed of 1200 r / min using a stirrer to ensure that the resin is evenly dispersed in the coating slurry;

[0167] S5, spray treatment:

[0168] Use a spraying device to evenly spray the coating obtained in S4 on the surface of the PTC electric heater with a spraying thickness of 0.1 mm;

[0169] S6, curing treatment:

[0170] The sprayed PTC electric heater was placed in an oven and baked at 170°C for 2.5 hours to solidify the coating and form a dense protective layer.

[0171] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0172] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. The surface protective coating of high-strength corrosion-resistant PTC electric heater is characterized by: The composition includes the following components in parts by weight: Graphene powder: 10-20 parts; Carbon nanotube powder: 5-15 parts; Inorganic resin: 30-50 parts; Alumina: 5-15 parts; Boron nitride: 2-8 parts; Dispersant: 0.5-2 parts; Silane coupling agent: 0.5-2 parts; Diluent: 10-20 parts.

2. The surface protective coating of the high-strength corrosion-resistant PTC electric heater according to claim 1 is characterized in that: The inorganic resin is one of a silicate resin and an aluminate resin.

3. The surface protective coating of the high-strength corrosion-resistant PTC electric heater according to claim 1 is characterized in that: The dispersant is one of polyethylene glycol and sodium lauryl sulfate.

4. The surface protective coating of the high-strength corrosion-resistant PTC electric heater according to claim 1 is characterized in that: The silane coupling agent is one of KH550 and KH560.

5. The surface protective coating of the high-strength corrosion-resistant PTC electric heater according to claim 1 is characterized in that: The diluent is one of ethanol or acetone.

6. A method for preparing a surface protective coating of a high-strength corrosion-resistant PTC electric heater, characterized in that: The following steps are involved: S1, Material preparation: Weigh each component material according to the above mass fraction and set aside; S2, Mixing and Dispersion: Add graphene powder, carbon nanotube powder, aluminum oxide, boron nitride, dispersant, and silane coupling agent to a high-speed disperser for dispersion at a speed of 2000-3000 r / min and a dispersion time of 30-60 min until the raw materials are evenly dispersed; S3, grinding treatment: The mixture obtained in S2 is ground using a grinder, using grinding beads with a diameter of 0.5-1.5 mm, until the fineness reaches less than 20 microns to obtain a coating slurry; S4, resin mixing: Add the inorganic resin and the diluent to the coating slurry obtained in S3, and stir with a stirrer at a speed of 1000-1500 r / min for 30-50 min to ensure that the resin is evenly dispersed in the coating slurry; S5, spray treatment: Use a spraying device to evenly spray the coating obtained in S4 on the surface of the PTC electric heater, with a spraying thickness of 0.1-0.3 mm; S6, curing treatment: Place the sprayed PTC electric heater in an oven and bake it at 150-200°C for 2-4 hours to solidify the coating and form a dense protective layer.