阅读说明：本技术 一种电绝缘性强的粉末涂料 (Powder coating with strong electrical insulation property ) 是由 王保军 拾振洪 李海洋 金传亮 回留柱 王家振 于 2020-07-07 设计创作，主要内容包括：本发明涉及一种电绝缘性强的粉末涂料,利用分子结构改性,对有机硅树脂进行改性,进一步掺杂陶瓷纳米颗粒对改性有机硅树脂进行联结,增加了电阻稳定性,陶瓷复合纳米颗粒的添加增强了粉末涂料的导热性能,不会导致改性有机硅树脂涂料的绝缘性下降,相反还加强了绝缘性能,随着温度的逐步升高,涂料的静力弯曲逐步趋于稳定,经过热物理化学反应使得有机硅树脂的硅氧键与纳米颗粒联结性能加强,保证了有机硅涂层在高温工作环境下具有优异的绝缘性能；涂层的电绝缘性能得到了保证,并能够承受冷热循环交替而保持膜层不被破坏,适合批量生产,大大降低了企业的生产成本,带来了更多的经济效益和社会效益。(The invention relates to a powder coating with strong electrical insulation, which modifies organic silicon resin by utilizing molecular structure modification, further dopes ceramic nano particles to connect the modified organic silicon resin, so that the resistance stability is increased, the heat conductivity of the powder coating is enhanced by adding the ceramic composite nano particles, the insulation property of the modified organic silicon resin coating is not reduced, the insulation property is also enhanced, the static bending of the coating gradually tends to be stable along with the gradual rise of the temperature, the silicon oxygen bond of the organic silicon resin and the nano particles are enhanced through thermal physical chemical reaction, and the excellent insulation property of an organic silicon coating under a high-temperature working environment is ensured; the electric insulation performance of the coating is ensured, the coating can bear the alternation of cold and hot cycles while the film layer is not damaged, the coating is suitable for batch production, the production cost of enterprises is greatly reduced, and more economic benefits and social benefits are brought.)

1. The powder coating with strong electrical insulation is characterized by comprising the following steps:

placing organic silicon resin into a reaction bottle, adding isophthalic acid, 2.0-2.2% of tris (hydroxymethyl) aminomethane, 0.5-0.6% of p-toluenesulfonic acid and 0.26-0.30% of xylene into the reaction bottle in mass percentages respectively accounting for 1.4-1.8% of the mass of the organic silicon resin, heating to 90-95 ℃, starting a stirrer, introducing carbon dioxide gas, keeping the temperature for 45-60 minutes, continuing to heat to 145 ℃ at 140 ℃ for reflux reaction for 2-3 hours, continuing to heat to 230 ℃ at the speed of 8-10 ℃/hour, recovering the evaporated solvent, cooling to 135 ℃ at the pH value of the system when the pH value of the system reaches 8.6-8.9, adding benzophenone accounting for 1.7-2.4% of the mass of the system, continuing to stir for 30-40 minutes, then adding the prepared ceramic composite nano-particles accounting for 0.074-0.078% of the mass of the system, rapidly stirring for 18-25 minutes at 1200-1400 rpm, cooling to 70-76 ℃, filtering, discharging and drying;

specifically, the preparation method of the ceramic composite nano-particles comprises the following steps:

weighing 10.8-11.2 g of zeolite powder, grinding the zeolite powder through a 250-ion-flow 350-mesh sieve, placing the zeolite powder in an oven at 70-80 ℃ for drying for 2-4 hours, placing the dried zeolite powder in a beaker, adding 80-85 ml of phosphate buffer solution into the beaker under the stirring of 400 revolutions per minute of 350-ion-flow 400, placing the beaker on a magnetic stirrer for continuously stirring and dispersing for 15-25 minutes, standing and precipitating for 5-8 hours, carrying out suction filtration, washing the obtained solid product for 4-6 times by using deionized water, placing the obtained solid product in a vacuum drying oven at 80-90 ℃ for drying for 10-12 hours, adding 43-45 ml of silicon nitride dispersion liquid into the dried material, heating the obtained product to 44-48 ℃ by using an electric heating furnace, continuously heating and stirring for 40-50 minutes, transferring the obtained product to a high-pressure reaction kettle, shaking the obtained product, setting the reaction temperature to be 240 ℃, keeping the temperature for reaction for 3-4 hours, naturally cooling along with the furnace after the reaction is finished, filtering, washing for 3-5 times by using absolute ethyl alcohol, drying for 8-10 hours in a drying oven at 60-80 ℃, grinding into powder, placing the powder in a crucible, feeding the powder into a muffle furnace for calcination, raising the temperature to 630-660 ℃ at a speed of 3.0-3.2 ℃/min, keeping the temperature for 2.0-3.0 hours, and naturally cooling.

2. A powder coating with high electrical insulation property as claimed in claim 1, wherein the pH value of the phosphate buffer solution is 6.6-6.7 in the preparation of the ceramic composite nano-particles.

3. The powder coating with strong electrical insulation property as claimed in claim 1, wherein the preparation method of the silicon nitride dispersion comprises the following steps: weighing 2.2-2.6 g of silicon nitride powder, placing the silicon nitride powder in 40-50 ml of absolute ethyl alcohol, continuously stirring for 30-40 minutes at the stirring speed of 300-350 r/min, then adding 5.0-5.5 ml of triethylamine, stirring for 20-30 minutes, and ultrasonically dispersing for 10-15 minutes.

4. A highly electrically insulating powder coating according to claim 1, wherein said ceramic composite nanoparticles have a particle size of between 17 nm and 20 nm.

5. The powder coating with strong electric insulation property as claimed in claim 1, wherein the silicone resin is prepared from the following components in parts by weight: 15-30 parts of methyltrichlorosilane, 55-62 parts of dimethyldichlorosilane, 35-48 parts of diphenyldichlorosilane, 140 parts of xylene 110-containing organic solvent, 10-20 parts of ethanol, 18-22 parts of n-butanol and 180 parts of distilled water 150-containing organic solvent.

Technical Field

The invention relates to the technical field of paint preparation, in particular to a powder paint with strong electrical insulation.

Background

The powder coating contains 100 percent of solid components, does not contain chemical solvents completely, does not pollute the environment, does not harm human bodies, is the most advanced and environment-friendly product at present, and is a development trend of the coating industry by replacing liquid coating with the coating coated in the powder industry. Along with rapid take-off of industrial development, the use frequency of various motors is higher and higher, and for electrical equipment, the insulativity is an indispensable assessment standard, so that the insulation performance of an insulation coating layer on the surface of the motor is also higher.

Silicone resins have excellent thermal stability, electrical insulation, aging resistance, and the like, and are becoming popular alternatives to epoxy resins, polyester resins, and other materials. However, the silicone resin has poor heat conductivity, a large amount of heat is generated during the operation of the motor, and the continuous high temperature increases the resistance, so that the insulating property of the coating is remarkably reduced. Under the comprehensive actions of high temperature, high voltage, discharge and the like, along with the aggravation of insulation aging, insulation failure is caused, the working performance of a motor is seriously influenced, and certain safety risk exists, so that a composite material with strong electrical insulation performance needs to be developed, and the composite material has great application value for the development of coatings.

Disclosure of Invention

The invention aims to provide a powder coating with strong electrical insulation, which utilizes molecular structure modification to modify organic silicon resin, further dopes ceramic nanoparticles to connect the modified organic silicon resin, enhances the heat-conducting property of the resin, increases the resistance stability, improves the insulating property of the coating, and has important significance for ensuring the working performance of the powder coating.

The invention is realized by the following technical scheme:

the powder coating with strong electrical insulation is realized by the following preparation process flow:

placing organic silicon resin into a reaction bottle, adding isophthalic acid, 2.0-2.2% of tris (hydroxymethyl) aminomethane, 0.5-0.6% of p-toluenesulfonic acid and 0.26-0.30% of xylene into the reaction bottle in mass percentages respectively accounting for 1.4-1.8% of the mass of the organic silicon resin, heating to 90-95 ℃, starting a stirrer, introducing carbon dioxide gas, keeping the temperature for 45-60 minutes, continuing to heat to 145 ℃ at 140 ℃ for reflux reaction for 2-3 hours, continuing to heat to 230 ℃ at the speed of 8-10 ℃/hour, recovering the evaporated solvent, cooling to 135 ℃ at the pH value of the system when the pH value of the system reaches 8.6-8.9, adding benzophenone accounting for 1.7-2.4% of the mass of the system, continuing to stir for 30-40 minutes, then adding the prepared ceramic composite nano-particles accounting for 0.074-0.078% of the mass of the system, rapidly stirring at 1200-1400 rpm for 18-25 min, cooling to 70-76 deg.C, filtering, discharging, and drying.

Specifically, the preparation method of the ceramic composite nano-particles comprises the following steps:

weighing 10.8-11.2 g of zeolite powder, grinding the zeolite powder through a 250-ion-resistant 350-mesh sieve, placing the zeolite powder in an oven at 70-80 ℃ for drying for 2-4 hours, placing the dried zeolite powder in a beaker, adding 80-85 ml of phosphate buffer solution with the pH value of 6.6-6.7 into the beaker under the stirring of 400 revolutions per minute of 350-ion-resistant powder, placing the beaker on a magnetic stirrer for continuously stirring and dispersing for 15-25 minutes, standing and precipitating for 5-8 hours, performing suction filtration, washing for 4-6 times by using deionized water to obtain a solid product, placing the solid product in a vacuum drying oven at 80-90 ℃ for drying for 10-12 hours, adding 43-45 ml of silicon nitride dispersion liquid into the dried material, heating the solid product to 44-48 ℃ by using an electric heating furnace, continuously heating and stirring for 40-50 minutes, transferring the solid product into a high-pressure reaction kettle, shaking, the reaction pressure is 1.2-1.3MPa, the reaction is carried out for 3-4 hours under the condition of heat preservation, the reaction is naturally cooled along with the furnace after the reaction is finished, the reaction product is filtered, washed for 3-5 times by using absolute ethyl alcohol, dried for 8-10 hours in a drying oven at the temperature of 60-80 ℃, ground into powder, placed in a crucible, sent into a muffle furnace for calcination, the temperature rise speed is 3.0-3.2 ℃/min, the temperature rises to 660 ℃ under the condition of 630 DEG and 660 ℃, the heat preservation is carried out for 2.0-3.0 hours, and the reaction product is; the preparation method of the silicon nitride dispersion liquid comprises the following steps: weighing 2.2-2.6 g of silicon nitride powder, placing the silicon nitride powder in 40-50 ml of absolute ethyl alcohol, continuously stirring for 30-40 minutes at the stirring speed of 300-350 r/min, then adding 5.0-5.5 ml of triethylamine, stirring for 20-30 minutes, and ultrasonically dispersing for 10-15 minutes.

The particle size of the ceramic composite nano-particles is 17-20 nanometers.

The organic silicon resin is prepared from the following components in parts by weight: 15-30 parts of methyltrichlorosilane, 55-62 parts of dimethyldichlorosilane, 35-48 parts of diphenyldichlorosilane, 140 parts of xylene 110-containing organic solvent, 10-20 parts of ethanol, 18-22 parts of n-butanol and 180 parts of distilled water 150-containing organic solvent.

Compared with the prior art, the invention has the following advantages: in order to solve the problem that the insulating property of the organic silicon resin powder coating can not be effectively guaranteed under the high-temperature condition, the invention provides the powder coating with strong electrical insulating property, the organic silicon resin is modified by utilizing the molecular structure modification, the ceramic nano particles are further doped to connect the modified organic silicon resin, the resistance stability is increased, the heat conducting property of the powder coating is enhanced by adding the ceramic composite nano particles, the insulating property of the modified organic silicon resin coating can not be reduced, the insulating property is also enhanced on the contrary, the static bending of the coating tends to be stable gradually along with the gradual rise of the temperature, the silicon-oxygen bond of the organic silicon resin and the nano particles are enhanced through the thermal physical-chemical reaction, and the excellent insulating property of the organic silicon coating under the high-temperature working environment is ensured; the electrical insulation performance of the coating is ensured, and the volume resistivity of the insulating coating reaches 17.6 multiplied by 10¹⁵Omega/cm, the breakdown strength reaches 55-60kV/mm, and the thermal conductivity reaches more than 1.57W/(m.K); the heat-resistant grade reaches C grade, the film can resist high temperature for a long time, and the film can bear the alternation of cold and hot cycles without being damaged. On one hand, the additional value of the insulativity of the powder coating is improved; inorganic composite nanoparticle addition, on the other handThe dosage is small, the effect is strong, the method is suitable for batch production, the production cost of an enterprise is greatly reduced, and more economic benefits and social benefits are brought; the application and development of the organic silicon resin in the production aspect of the high-performance insulating coating are promoted, the upgrading of the product performance is promoted, the practical significance of improving the functionality of the insulating coating and improving the market competitiveness can be realized, the rapid development and the resource sustainable development of the modern coating industry and the environmental protection industry are remarkably promoted, and the organic silicon resin insulating coating is a technical scheme which is extremely worthy of popularization and use.

Drawings

In order to facilitate understanding for those skilled in the art, the present invention will be further described with reference to the accompanying drawings.

FIG. 1 is a graph showing the relationship between the volume resistivity of the powder coating prepared by the present invention and the control and the addition amount of the ceramic composite material at 220 ℃.

Detailed Description

In order to make the objects, technical solutions and effects of the present invention clearer and clearer, the present invention is further described with reference to specific embodiments, and it should be understood that the specific embodiments described herein are only used for explaining the present invention and are not used for limiting the technical solutions provided by the present invention.