阅读说明：本技术 一种电子绝缘粉末涂料及其制备方法 (Electronic insulation powder coating and preparation method thereof ) 是由 曹彩艳 安一新 张妙 于 2021-07-14 设计创作，主要内容包括：本发明属于涂料领域,具体涉及一种电子绝缘粉末涂料及其制备方法。所述电子绝缘粉末涂料的原料及其重量百分含量为：环氧树脂50-60％,改性硅酸盐5-16％,固化剂5-6％,流平剂0.8-1.2％,增光剂0.8-1.0％,消泡剂2-4％,钛白颜料20-28％,硫酸钡填料0.5-20％；所述改性硅酸盐由硅酸盐经硅烷偶联剂改性获得。该粉末涂料具备优异的耐化学性能以及高电阻率,使得本发明的粉末涂料对医疗电子元件具有较好的保护效果,使之能够延长设备使用寿命。(The invention belongs to the field of coatings, and particularly relates to an electronic insulation powder coating and a preparation method thereof. The electronic insulation powder coating comprises the following raw materials in percentage by weight: 50-60% of epoxy resin, 5-16% of modified silicate, 5-6% of curing agent, 0.8-1.2% of flatting agent, 0.8-1.0% of brightener, 2-4% of defoaming agent, 20-28% of titanium white pigment and 0.5-20% of barium sulfate filler; the modified silicate is obtained by modifying silicate with a silane coupling agent. The powder coating has excellent chemical resistance and high resistivity, so that the powder coating has a good protection effect on medical electronic elements, and the service life of equipment can be prolonged.)

1. The electronic insulation powder coating is characterized by comprising the following raw materials in percentage by weight:

50-60% of epoxy resin, 5-16% of modified silicate, 5-6% of curing agent, 0.8-1.2% of flatting agent, 0.8-1.0% of brightener, 2-4% of defoaming agent, 20-28% of titanium white pigment and 0.5-20% of barium sulfate filler;

the modified silicate is obtained by modifying silicate with a silane coupling agent.

2. The electronically insulating powder coating according to claim 1, characterized in that the process for the preparation of the modified silicate comprises in particular:

dissolving a silane coupling agent into an acidic solution, adding silicate, stirring for reacting for 2-5h, filtering, washing and drying to obtain modified silicate;

the dosage of the silane coupling agent is 1-5% of the mass of the silicate.

3. The electronically insulating powder coating of claim 1, wherein the curing agent is dicyandiamide, adipic acid dihydrazide.

4. The electronically insulating powder coating of claim 1, wherein the defoamer is benzoin.

5. The preparation method of the electronic insulation powder coating is characterized by comprising the following steps:

stirring and mixing raw materials of epoxy resin, modified silicate, a curing agent, a flatting agent, a brightener, a defoaming agent, a titanium white pigment and barium sulfate to obtain a mixture;

extruding the mixture through an extruder to obtain a block material, and grinding the block material to obtain the powder coating with the particle size of 30-40 mu m.

6. The method for preparing an electronically insulating powder coating according to claim 5, wherein the temperature of the extrusion process is 90-110 ℃.

Technical Field

The invention belongs to the field of coatings, and particularly relates to an electronic insulation powder coating and a preparation method thereof.

Background

In recent years, with the increase of environmental protection, the environmental protection requirement is higher and higher, and the change of paint into powder becomes the development trend of the related coating industries. In the past, when the insulation treatment is needed in the electronic industry, the motor industry, the automobile industry, the high-voltage electrical appliances and the like, paint spraying is usually selected. Because the paint is related to the temperature and the humidity of the environment during the batching, the phenomena like pinholes, bubbles, sagging and the like due to the unstable factors of the coating quality exist; when the product is processed in a large scale, due to the influence of the dosage of the curing agent, the serious waste phenomenon can occur when the work is not finished; the environmental pollution is serious, the solvent is volatilized, the manual operation is carried out, the labor intensity is high, the utilization rate of the paint is only 30-40 percent, even lower, the cost is high and the like. With the increasing environmental requirements, enterprises are beginning to find coating processes that can replace traditional paint spraying. The powder coating gradually becomes the selection direction of enterprises due to the characteristics of low pollution, nearly zero VOC emission and the like. The powder coating occupies higher and higher market share in the insulating powder coating for the electronic and motor, and the coated product is widely applied to various fields of the electronic, motor, automobile industry, high-voltage electric appliance and the like.

The insulating powder coating is used for electric insulation of products such as motors, high-voltage switch cabinets, transformers, electric welding machines, electronic elements, copper bars, aluminum bars, electromagnetic wires and the like. The powder coating is required to have higher insulating property and better chemical resistance, but the resistivity insulating property, the chemical resistance and the chemical resistance of the powder coating used in the market are required to be improved after the powder coating is sprayed to form a film.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to solve the technical problems that the powder coating in the prior art has poor resistivity and insulation property and weak chemical corrosion resistance after being sprayed; according to the invention, silane coupling agent is adopted to modify silicate to obtain modified silicate filler, and the modified silicate filler is matched with raw materials such as epoxy resin, barium sulfate filler, curing agent and leveling agent to obtain the powder coating with high resistivity and strong chemical corrosion resistance.

In order to achieve the purpose, the invention provides an electronic insulation powder coating which comprises the following raw materials in percentage by weight:

50-60% of epoxy resin, 5-16% of modified silicate, 5-6% of curing agent, 0.8-1.2% of flatting agent, 0.8-1.0% of brightener, 2-4% of defoaming agent, 20-28% of titanium white pigment and 0.5-20% of barium sulfate filler;

the modified silicate is obtained by modifying silicate with a silane coupling agent.

Further, the preparation method of the modified silicate specifically comprises the following steps:

dissolving a silane coupling agent into an acidic solution, adding silicate, stirring for reacting for 2-5h, filtering, washing and drying to obtain modified silicate;

the dosage of the silane coupling agent is 1-5% of the mass of the silicate.

Further, the curing agent is dicyandiamide and adipic acid dihydrazide.

Further, the defoaming agent is benzoin.

Based on the same inventive concept, the embodiment of the invention also provides a preparation method of the electronic insulation powder coating, and the preparation method specifically comprises the following steps:

stirring and mixing raw materials of epoxy resin, modified silicate, a curing agent, a flatting agent, a brightener, a defoaming agent, a titanium white pigment and barium sulfate to obtain a mixture;

extruding the mixture through an extruder to obtain a block material, and grinding the block material to obtain the powder coating with the particle size of 30-40 mu m.

Further, the temperature of the extrusion process is 90-110 ℃.

Has the advantages that:

according to the invention, silicate modified by silane coupling agent is used as filler, and is mixed with raw materials such as epoxy resin, curing agent, flatting agent and the like, and then extruded at high temperature, and then ground to obtain powder coating, the modified silicate filler is used, and the outer layer is a chemical adsorption layer with silane coupling agent hydrolysate, so that the binding force between the filler and other materials can be greatly improved, the compactness of the powder coating is improved, the resistivity of the powder coating can be improved, and the resistivity is more than 2.0 x 10⁹Omega cm, and has strong chemical corrosion resistance, the chemical corrosion resistance is improved by the mutual matching of the raw materials, and the salt spray corrosion resistance is carried out by adopting 5 percent NaCl solution for 500 hours, so that the corrosion is deepThe degree is less than 1 mm.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to specific embodiments, but the scope of the present invention is not limited to the following specific embodiments.

Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.

Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.

In the embodiment of the present invention, the epoxy resin used is two-step epoxy resin 704 from south asian resin limited, the curing agent is dicyandiamide, the leveling agent is 588, and the gloss-enhancing agent is 701, it being understood that other general-purpose agents may be used for the leveling agent and the gloss-enhancing agent.

The preparation method of the modified silicate comprises the following steps: dissolving a silane coupling agent in an acidic solution, adding silicate, stirring for reacting for 2-5h, filtering, washing and drying to obtain the modified silicate. Wherein the silane coupling agent is any one of vinyl triethoxysilane, vinyl trimethoxysilane or vinyl tri (beta-methoxyethoxy) silane, and the silicate is one or more of feldspar, mica, clay and pyroxene. The modified silicates employed in the examples of the invention were: dissolving vinyl triethoxysilane in an acid solution, adding the crushed feldspar, stirring for reaction for 4 hours, filtering, washing filter residues with deionized water, and drying to obtain the modified silicate.

The following is a further description with specific examples.

Example 1

The formula of the electronic insulating powder coating comprises the following components: 550 parts of two-step epoxy resin, 55 parts of curing agent, 10 parts of flatting agent, 2 parts of benzoin, 5 parts of brightener and 100 parts of modified silicate; 220 parts of titanium dioxide and 58 parts of barium sulfate.

The preparation method of the electronic insulating powder coating comprises the following steps: stirring and mixing the two-step method raw materials of epoxy resin, modified silicate, a curing agent, a flatting agent, a brightener, a defoaming agent, a titanium white pigment and barium sulfate to obtain a mixture;

extruding the mixture by an extruder at the temperature of 90 ℃ to obtain a block material, and grinding the block material to obtain a powder coating with the particle size of about 35 mu m.

Example 2

The formula of the electronic insulating powder coating comprises the following components: 550 parts of two-step epoxy resin, 55 parts of curing agent, 10 parts of flatting agent, 2 parts of benzoin, 5 parts of brightener and 100 parts of modified silicate; 220 parts of titanium dioxide and 8 parts of barium sulfate.

The preparation method of the electronic insulating powder coating comprises the following steps: stirring and mixing the two-step method raw materials of epoxy resin, modified silicate, a curing agent, a flatting agent, a brightener, a defoaming agent, a titanium white pigment and barium sulfate to obtain a mixture;

extruding the mixture by an extruder at the temperature of 110 ℃ to obtain a block material, and grinding the block material to obtain a powder coating with the particle size of about 35 mu m.

Comparative example 1

The formula of the electronic insulating powder coating comprises the following components: 550 parts of two-step epoxy resin, 55 parts of curing agent, 10 parts of flatting agent, 2 parts of benzoin, 5 parts of brightener, 220 parts of titanium dioxide, 156 parts of barium sulfate and 2 parts of PE wax.

The preparation method of the electronic insulating powder coating comprises the following steps: stirring and mixing the two-step method raw materials of epoxy resin, a curing agent, a flatting agent, a brightener, a defoaming agent, titanium white pigment and barium sulfate to obtain a mixture;

extruding the mixture by an extruder at the temperature of 110 ℃ to obtain a block material, and grinding the block material to obtain a powder coating with the particle size of about 35 mu m.

Comparative example 2

The formula of the electronic insulating powder coating comprises the following components: 550 parts of two-step epoxy resin, 55 parts of curing agent, 10 parts of flatting agent, 2 parts of benzoin, 5 parts of brightener, 220 parts of titanium dioxide, 156 parts of barium sulfate and 100 parts of unmodified silicate filler.

The preparation method of the electronic insulating powder coating comprises the following steps: stirring and mixing the raw materials to obtain a mixture; extruding the mixture by an extruder at the temperature of 110 ℃ to obtain a block material, and grinding the block material to obtain a powder coating with the particle size of about 35 mu m.

After the powder coatings obtained in examples 1 and 2 and comparative examples 1 and 2 are sprayed to form a film, the film is cured for 10min at 200 ℃, and the mechanical property, the corrosion resistance and the conductivity of the film are detected, wherein the hardness of the coating is detected by adopting a GB/T6739 standard, and the detection condition is a triangular pencil; adopting a GB/T9754 watch hand to detect the glossiness, wherein the detection condition is 60 degrees; detecting the impact resistance by adopting a GB/T1732 standard; soaking for 168h under the condition of 5% NaOH solution to detect the alkali resistance; soaking in 3% HCl solution for 168h to detect acid resistance; the results of the salt spray corrosion resistance test for 500 hours in the presence of 5% NaCl solution are shown in Table 1.

TABLE 1 coating Properties of the powder coatings of the examples and comparative examples

As can be seen from Table 1, the powder coating of the examples of the present invention has increased salt spray corrosion resistance and electrical resistivity compared to the comparative examples, and from the viewpoint of raw material composition, the examples of the present invention reduce the amount of barium sulfate, and without adding PE wax, the powder coating obtained has a smaller specific gravity, and the spray area can be increased by 5-10%.

The above-mentioned embodiments are only preferred embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered as the technical scope of the present invention, and equivalents and modifications of the technical solutions and concepts of the present invention should be covered by the scope of the present invention.