Novel antistatic environment-friendly solventless coating and preparation method thereof

Abstract

The invention relates to the technical field of environment-friendly solventless coatings. The antistatic novel environment-friendly solvent-free coating is prepared from the following components in percentage by mass: 30 to 45 percent of polyurethane acrylate oligomer, 15 to 25 percent of organic silicon modified acrylate resin, 3 to 8 percent of ionic liquid type antistatic agent, 0.5 to 2.5 percent of carbon nanotube conductive filler, 0.3 to 1.2 percent of nano silicon dioxide, 2 to 5 percent of dispersing agent, 0.1 to 0.8 percent of flatting agent, 0.05 to 0.3 percent of defoaming agent and the balance of solvent. And the balance of reactive diluent. According to the invention, through the synergistic effect of the ionic liquid type antistatic agent and the carbon nanotube conductive filler, the volume resistance of the coating is # imgabs0 #, and the stable antistatic capability of the surface of the coating is ensured. According to the invention, the surface modification technology of the carbon nanotubes is adopted, and the silane coupling agent is utilized to carry out functionalization treatment on the carbon nanotubes, so that the carbon nanotubes can be uniformly dispersed in a coating system to form a stable conductive network structure, thereby improving the conductive uniformity and long-term antistatic effect of the coating.

Description

Technical Field

[0001] The invention relates to the technical field of environmentally friendly solvent-free coatings, and in particular to a novel antistatic environmentally friendly solvent-free coating and a preparation method thereof. Background Art

[0002] Antistatic coating is a special functional coating material, which is widely used in industries such as electronic manufacturing, precision instruments, medical equipment, aerospace, semiconductor production, explosion-proof places, etc. It is mainly used to prevent static electricity accumulation and reduce the safety hazards caused by electrostatic discharge (ESD). For example, in the electronic manufacturing industry, static electricity may damage integrated circuit chips and affect the stable operation of precision instruments; in the medical field, static electricity may cause dust adsorption and affect the cleanliness of the dust-free environment; in the chemical and energy industries, static electricity accumulation may even cause spark discharge and lead to explosion accidents. Therefore, antistatic coatings with stable antistatic ability, high mechanical strength, and environmental protection and pollution-free have become an important research direction in this field.

[0003] At present, antistatic coatings on the market mainly use conductive filler modification, ionic antistatic agents and copolymerization modification to improve the antistatic performance of the coating. However, the traditional method has the disadvantages that the ionic antistatic agent is easy to migrate and lose, and the conductive filler is easy to agglomerate or settle, which causes the antistatic performance of the coating to gradually decrease during use and cannot meet the needs of long-term stable use.

[0004] Therefore, we propose a novel antistatic and environmentally friendly solvent-free coating and a preparation method thereof. Summary of the invention

[0005] 1. Technical issues to be resolved The purpose of the present invention is to provide a novel antistatic environmentally friendly solvent-free coating and a preparation method thereof, so as to solve the problems raised in the above-mentioned background technology.

[0006] (II) Technical solution To achieve the above object, the present invention provides the following technical solutions: A novel antistatic environmentally friendly solvent-free coating, comprising the following components in percentage by mass: 30-45% of polyurethane acrylate oligomer, 15-25% of organosilicon-modified acrylate resin, 3-8% of ionic liquid antistatic agent, 0.5-2.5% of carbon nanotube conductive filler, 0.3-1.2% of nano silicon dioxide, 2-5% of dispersant, 0.1-0.8% of leveling agent, 0.05-0.3% of defoamer, and the balance is active diluent; wherein the carbon nanotube conductive filler is surface treated with a silane coupling agent, the aspect ratio is controlled at 100-200, and the specific surface area is ≥200m² / g; the ionic liquid is a compound of 1-butyl-3-methylimidazole bistrifluoromethanesulfonyl imide salt and 1-ethyl-3-methylimidazole tetrafluoroborate in a mass ratio of 2:1; the active diluent is a mixture of trimethylolpropane triacrylate and tripropylene glycol diacrylate in a ratio of 3:2; the volume resistivity of the coating is 2.5-3.0. , VOC content <15g / L, cured film pencil hardness ≥4H.

[0007] A method for preparing a novel antistatic environmentally friendly solvent-free coating comprises the following steps: (1) Pre-dispersion treatment: preheat the polyurethane acrylate oligomer and the silicone-modified acrylate resin at 60-70°C for 30 minutes, add the active diluent preheated to 50°C, and stir at 400-600 rpm to form a homogeneous base material; (2) Gradient dispersion: Add the carbon nanotube conductive filler to the base material three times. After each addition, disperse it at a high speed of 1200 rpm for 10 min, then switch to a three-roll mill for three passes of grinding, and adjust the roller gap to 50 μm, 30 μm, and 15 μm respectively. (3) Construction of antistatic system: Under nitrogen protection, the ionic liquid antistatic agent and nano-silicon dioxide were premixed in a ratio of 1:0.3, heated to 80°C at a rate of 0.5°C / min and maintained for 15 min, and then injected into the dispersion system by pulse feeding; (4) Integration of functional additives: After the system is cooled to below 45°C, dispersant, leveling agent and defoamer are added in sequence, and mixed for 40 minutes using a planetary mixer in a composite motion mode of revolution 20 rpm + rotation 800 rpm; (5) Viscosity control: Monitor the viscosity of the system through an online rheometer. When the viscosity reaches 1500-2000 mPa·s, start the ultrasonic assisted degassing device for 15-20 minutes; (6) Maturation treatment: Transfer the material to a constant temperature aging tank and place it at 35±2℃ for 24 hours, stirring at a low speed for 5 minutes every 4 hours.

[0008] As a preferred technical solution, the preheating in step (1) adopts segmented temperature control: the temperature is raised to 50°C at a rate of 2°C / min in the first 10 minutes, then raised to 65°C at a rate of 1°C / min and maintained for 15 minutes, and finally raised to 70°C at a rate of 0.5°C / min; the stirring paddle adopts a double-layer serrated structure, the ratio of the lower paddle diameter to the container diameter is 0.6:1, the upper layer is 0.4:1, and the distance between the two paddles is 1 / 3 of the container height.

[0009] As a preferred technical solution, the timings of adding carbon nanotubes three times in step (2) are: the first time when the base material temperature reaches 60°C, 50% of the total amount is added; the second time, 30% is added before the second pass of three-roll grinding; and the third time, 20% is added after the grinding is completed; different dispersion procedures are used after each addition: a dispersion disk with a diameter of Φ25 mm is used for the first time, replaced with a Φ18 mm conical disk for the second time, and a Φ30 mm flat disk for the third time.

[0010] As a preferred technical solution, the specific parameters of the pulse feeding in step (3) are: feeding frequency 2 Hz, single pulse duration 0.5 s, interval time 1.5 s, the feeding pipe outlet is designed as a rotatable fan-shaped nozzle, the rotation speed is linked with the feeding pump frequency and controlled at 30-60 rpm; the nano-silicon dioxide is pre-treated with plasma, the treatment power is 300 W, the time is 5 min, and a mixed gas with a volume ratio of argon to oxygen of 4:1 is introduced.

[0011] As a preferred technical solution, in step (4), the speed ratio of the revolution to the rotation of the planetary mixer is controlled according to a time program: 1:40 in the first 10 minutes, adjusted to 1:60 in the middle 20 minutes, and reduced to 1:30 in the last 10 minutes; 6 groups of vertical baffles are set on the inner wall of the mixing tank, the width of the baffle is 1 / 10 of the tank diameter, and the height is 80% of the liquid level.

[0012] As a preferred technical solution, the ultrasonic treatment in step (5) adopts a dual-frequency composite mode: 20kHz and 40kHz work alternately, each frequency acts for 5 minutes, and pauses for 30 seconds when alternating; the insertion depth of the ultrasonic probe is 2 / 3 of the liquid level, the power density is controlled at 0.5-0.8W / cm³, and the system temperature is maintained at ≤40°C during the treatment process.

[0013] As a preferred technical solution, in step (6), the aging process adopts a dynamic temperature field: the temperature is maintained at 35°C for the first 8 hours, then increased to 38°C at a rate of 0.5°C / h for 4 hours, then decreased to 32°C at a rate of 1°C / h, and finally maintained at 34±0.5°C for 12 hours; during stirring, the linear speed of the paddle is controlled at 0.3-0.5 m / s, the stirring shaft is designed as a hollow structure, and 35°C circulating water is passed into the interior.

[0014] As a preferred technical solution, the whole process quality monitoring includes: after step (2), the fineness is detected to be ≤15μm; after step (4), the viscosity deviation is measured to be ≤±5%; after aging, the volume resistivity fluctuation range is tested to be ≤±0.5 orders of magnitude in step (6); the online detection data is uploaded to the MES system in real time, and the process parameter adjustment program is automatically triggered when any parameter exceeds the set threshold.

[0015] (III) Beneficial effects Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention uses the synergistic effect of ionic liquid antistatic agent and carbon nanotube conductive filler to increase the volume resistivity of the coating. , ensuring the stable antistatic ability of the coating surface. Compared with traditional antistatic coatings, this solution avoids the problem of antistatic performance attenuation caused by migration, loss or environmental humidity of traditional antistatic agents. It adopts the surface modification technology of carbon nanotubes and uses silane coupling agents to functionalize carbon nanotubes so that they can be evenly dispersed in the coating system to form a stable conductive network structure, thereby improving the conductive uniformity and long-term antistatic effect of the coating. Even after long-term use or mechanical friction, the coating can still maintain stable antistatic performance, avoiding safety hazards caused by static electricity accumulation, such as damage to electronic components, spark discharge or dust explosion, and meeting the high standards of electronic manufacturing, precision instruments and explosion-proof places.

[0016] 2. The present invention adopts a solvent-free formula, completely abandoning the common organic solvents in the traditional coating system, such as volatile organic compounds (VOCs) such as benzene, toluene, and xylene, ensuring that the VOC content of the coating is less than 15g / L, which is far lower than the national environmental protection regulations (GB18581-2020) and European and American ROHS and REACH standards, and has excellent environmental performance. In terms of system design, all active diluents can fully participate in the curing reaction, which not only reduces the release of organic volatiles, but also improves the density and durability of the coating after curing and film formation. Compared with traditional solvent-based antistatic coatings, this solution can not only effectively reduce environmental pollution during the construction process, but also reduce the health risks of construction workers, and avoid occupational diseases such as poisoning and allergies caused by long-term contact with organic solvents. In addition, the coating can still maintain good film-forming properties under low-temperature curing conditions, while achieving green environmental protection and taking into account the needs of energy saving and consumption reduction, providing a reliable technical path for the sustainable development of the coating industry.

[0017] 3. This coating system greatly improves the mechanical strength of the coating through the strengthening effect of nano-silica filler, so that it can maintain excellent durability in various harsh application environments. Experimental tests show that the cured coating has a pencil hardness ≥ 4H, and it will not easily scratch or peel off even under long-term friction, collision or mechanical stress, ensuring long-term good surface quality. In addition, the introduction of nano-silica not only enhances the impact resistance of the coating, but also optimizes the density of the coating, thereby improving its chemical corrosion resistance, enabling it to effectively resist acid, alkali, salt spray and solvent erosion. This improvement in chemical resistance allows the coating to be widely used in precision electronic equipment, medical equipment, aerospace materials and other fields, ensuring that the coating maintains stable performance during long-term use, extending the service life of the equipment and reducing maintenance costs.

[0018] 4. The present invention adopts an optimized nanofiller dispersion process, including gradient dispersion, three-roll grinding, ultrasonic-assisted degassing and other technical means to ensure the uniform distribution of conductive fillers and antistatic agents in the coating system. Compared with traditional antistatic coatings, this solution effectively reduces the internal stress of the system through dynamic temperature field aging technology, making it difficult for the coating to settle, stratify or agglomerate during storage, ensuring long-term storage stability. During the preparation process, the MES system is used for real-time data monitoring, and key indicators such as viscosity, fineness, and resistivity of the coating are monitored online to ensure the quality consistency of each batch of coating, thereby improving the reliability of industrial production of the product. The application of this technology enables the coating to maintain uniform physical and chemical properties for a long time, reducing quality fluctuations caused by batch differences. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is the overall process flow chart of the present invention; Figure 2 This is a schematic diagram of the pulse feeding system of the present invention; Figure 3 It is a timing diagram of the dynamic temperature field of the present invention. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] Example 1 According to the attached Figure 1-3 As shown, the present invention provides a novel antistatic environmentally friendly solvent-free coating and a preparation method thereof, wherein the coating is composed of the following components in percentage by mass: Polyurethane acrylate oligomer 30-45%, silicone modified acrylate resin 15-25%, ionic liquid antistatic agent 3-8%, carbon nanotube conductive filler 0.5-2.5%, nano silicon dioxide 0.3-1.2%, dispersant 2-5%, leveling agent 0.1-0.8%, defoamer 0.05-0.3%, the balance is active diluent; wherein the carbon nanotube conductive filler is surface treated with silane coupling agent, the aspect ratio is controlled at 100-200, and the specific surface area is ≥200m² / g; the ionic liquid is 1-butyl-3-methylimidazole bistrifluoromethanesulfonyl imide salt and 1-ethyl-3-methylimidazole tetrafluoroborate in a mass ratio of 2:1; the active diluent is a mixture of trimethylolpropane triacrylate and tripropylene glycol diacrylate in a ratio of 3:2; the volume resistivity of the coating is 20 ... , VOC content <15g / L, cured film pencil hardness ≥4H.

[0023] The preparation method comprises the following steps: (1) Pre-dispersion treatment: preheat the polyurethane acrylate oligomer and the silicone-modified acrylate resin at 60-70°C for 30 minutes, add the active diluent preheated to 50°C, and stir at 400-600 rpm to form a homogeneous base material; (2) Gradient dispersion: Add the carbon nanotube conductive filler to the base material three times. After each addition, disperse it at a high speed of 1200 rpm for 10 min, then switch to a three-roll mill for three passes of grinding, and adjust the roller gap to 50 μm, 30 μm, and 15 μm respectively. (3) Construction of antistatic system: Under nitrogen protection, the ionic liquid antistatic agent and nano-silicon dioxide were premixed in a ratio of 1:0.3, heated to 80°C at a rate of 0.5°C / min and maintained for 15 min, and then injected into the dispersion system by pulse feeding; (4) Integration of functional additives: After the system is cooled to below 45°C, dispersant, leveling agent and defoamer are added in sequence, and mixed for 40 minutes using a planetary mixer in a composite motion mode of revolution 20 rpm + rotation 800 rpm; (5) Viscosity control: Monitor the viscosity of the system through an online rheometer. When the viscosity reaches 1500-2000 mPa·s, start the ultrasonic assisted degassing device for 15-20 minutes; (6) Maturation treatment: Transfer the material to a constant temperature aging tank and place it at 35±2℃ for 24 hours, stirring at a low speed for 5 minutes every 4 hours.

[0024] Example 2 On the basis of Example 1, the preheating in step (1) adopts segmented temperature control: the temperature is raised to 50°C at a rate of 2°C / min in the first 10 minutes, then raised to 65°C at a rate of 1°C / min and maintained for 15 minutes, and finally raised to 70°C at a rate of 0.5°C / min; the stirring paddle adopts a double-layer serrated structure, the ratio of the lower blade diameter to the container diameter is 0.6:1, the upper layer is 0.4:1, and the distance between the two paddles is 1 / 3 of the height of the container.

[0025] The timings of adding carbon nanotubes three times in step (2) are as follows: 50% of the total amount is added for the first time when the base material temperature reaches 60°C, 30% is added for the second time before the second pass of three-roller grinding, and 20% is added for the third time after the grinding is completed; different dispersion procedures are used after each addition: a dispersion disk with a diameter of Φ25 mm is used for the first time, replaced with a Φ18 mm conical disk for the second time, and a Φ30 mm flat disk for the third time.

[0026] Example 3 On the basis of Example 1, the specific parameters of the pulse feeding in step (3) are: feeding frequency 2 Hz, single pulse duration 0.5 s, interval time 1.5 s, the feeding pipe outlet is designed as a rotatable fan-shaped nozzle, the rotation speed is linked with the feeding pump frequency and controlled at 30-60 rpm; the nano-silicon dioxide is pre-treated with plasma, the treatment power is 300 W, the time is 5 min, and a mixed gas with a volume ratio of argon to oxygen of 4:1 is introduced.

[0027] In step (4), the speed ratio of the planetary mixer's revolution to rotation is controlled according to a time program: 1:40 for the first 10 minutes, adjusted to 1:60 for the middle 20 minutes, and reduced to 1:30 for the last 10 minutes; 6 sets of vertical baffles are set on the inner wall of the mixing tank, the baffle width is 1 / 10 of the tank diameter, and the height is 80% of the liquid level.

[0028] In step (5), the ultrasonic treatment adopts a dual-frequency composite mode: 20kHz and 40kHz work alternately, each frequency acts for 5 minutes, and pauses for 30 seconds when alternating; the insertion depth of the ultrasonic probe is 2 / 3 of the liquid surface height, the power density is controlled at 0.5-0.8W / cm³, and the system temperature is maintained at ≤40°C during the treatment process.

[0029] Example 4 On the basis of Example 1, a dynamic temperature field is adopted in the aging process in step (6): the temperature is maintained at 35°C for the first 8 hours, then increased to 38°C at a rate of 0.5°C / h for 4 hours, then decreased to 32°C at a rate of 1°C / h, and finally maintained at 34±0.5°C for 12 hours; during stirring, the linear speed of the paddle is controlled at 0.3-0.5 m / s, the stirring shaft is designed as a hollow structure, and 35°C circulating water is passed into the interior.

[0030] The whole process quality monitoring includes: after step (2), the fineness is tested to be ≤15μm; after step (4), the viscosity deviation is tested to be ≤±5%; after aging, the volume resistivity fluctuation range is tested to be ≤±0.5 orders of magnitude; the online detection data is uploaded to the MES system in real time, and the process parameter adjustment program is automatically triggered when any parameter exceeds the set threshold.

[0031] Comparison of key step parameters of Examples 1 to 4: as shown in the following table: Table 1 Comparison of key step parameters Preheating treatment: Example 2 improves the compatibility of the resin by staged temperature control, and the double-layer paddles enhance the shearing effect.

[0032] Carbon nanotube dispersion: Example 2: Carbon nanotubes are added in stages and the size of the dispersion disk is adjusted to improve the uniformity of filler dispersion.

[0033] Antistatic agent addition: Example 3: Pulse feeding and plasma treatment of nano-SiO 2 , enhance the interface bonding between antistatic agent and resin.

[0034] Planetary stirring: Example 3 dynamically adjusts the stirring speed ratio and optimizes the mixing efficiency in combination with the baffle design.

[0035] Ultrasonic degassing: Example 4 Dual-frequency ultrasound synergistically improves the efficiency of bubble removal and avoids overheating.

[0036] Ripening process: Example 4 promotes system stabilization through a dynamic temperature field and a temperature-controlled stirring shaft.

[0037] The comparison of key performance indicators of Examples 1 to 4 is shown in the following table: Table 2 Key performance indicators comparison table Volume resistivity: Examples 2 to 4 gradually reduce the resistivity through process optimization, and Example 4 reaches the lowest resistivity of 5×10 5 Ω・cm.

[0038] VOC content: All examples meet environmental protection requirements, and Example 4 further reduces VOC due to improved dispersion efficiency.

[0039] Cured film hardness: Examples 3 and 4 are hardened by nano-SiO 2 The pretreatment and aging processes are optimized, and the hardness is increased to 3H.

[0040] Dispersion fineness: Examples 2 to 4 are gradually refined to 8 μm, reflecting the improvement of the dispersion process.

[0041] System viscosity: In Example 4, due to the adjustment of the ultrasound and aging process, the viscosity range shifted to a higher value but was still controllable.

[0042] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A new type of antistatic environmentally friendly solvent-free coating, characterized by: The invention is composed of the following components in percentage by mass: 30-45% of polyurethane acrylate oligomer, 15-25% of organosilicon-modified acrylate resin, 3-8% of ionic liquid antistatic agent, 0.5-2.5% of carbon nanotube conductive filler, 0.3-1.2% of nano silicon dioxide, 2-5% of dispersant, 0.1-0.8% of leveling agent, 0.05-0.3% of defoaming agent, and the balance of active diluent; The carbon nanotube conductive filler is surface treated with a silane coupling agent, the aspect ratio is controlled at 100-200, and the specific surface area is ≥200m² / g; the ionic liquid is a compound of 1-butyl-3-methylimidazole bistrifluoromethanesulfonyl imide salt and 1-ethyl-3-methylimidazole tetrafluoroborate in a mass ratio of 2:1; the active diluent is a mixture of trimethylolpropane triacrylate and tripropylene glycol diacrylate in a mass ratio of 3:2; the volume resistivity of the coating is , VOC content <15g / L, cured film pencil hardness ≥4H.

2. A method for preparing a novel antistatic environmentally friendly solvent-free coating, characterized in that: The following steps are involved: (1) Pre-dispersion treatment: preheat the polyurethane acrylate oligomer and the silicone-modified acrylate resin at 60-70°C for 30 minutes, add the active diluent preheated to 50°C, and stir at 400-600 rpm to form a homogeneous base material; (2) Gradient dispersion: Add the carbon nanotube conductive filler to the base material three times. After each addition, disperse it at a high speed of 1200 rpm for 10 min, then switch to a three-roll mill for three passes of grinding, and adjust the roller gap to 50 μm, 30 μm, and 15 μm respectively. (3) Construction of antistatic system: Under nitrogen protection, the ionic liquid antistatic agent and nano-silicon dioxide were premixed in a ratio of 1:0.3, heated to 80°C at a rate of 0.5°C / min and maintained for 15 min, and then injected into the dispersion system by pulse feeding; (4) Integration of functional additives: After the system is cooled to below 45°C, dispersant, leveling agent and defoamer are added in sequence, and mixed for 40 minutes using a planetary mixer in a composite motion mode of revolution 20 rpm + rotation 800 rpm; (5) Viscosity control: Monitor the viscosity of the system through an online rheometer. When the viscosity reaches 1500-2000 mPa·s, start the ultrasonic assisted degassing device for 15-20 minutes; (6) Maturation treatment: Transfer the material to a constant temperature aging tank and place it at 35±2℃ for 24 hours, stirring at a low speed for 5 minutes every 4 hours.

3. The method for preparing a novel antistatic environmentally friendly solvent-free coating according to claim 2, characterized in that: The preheating in step (1) adopts segmented temperature control: the temperature is raised to 50°C at a rate of 2°C / min in the first 10 minutes, then raised to 65°C at a rate of 1°C / min and maintained for 15 minutes, and finally raised to 70°C at a rate of 0.5°C / min; the stirring paddle adopts a double-layer sawtooth structure, the ratio of the lower paddle diameter to the container diameter is 0.6:1, the upper paddle diameter is 0.4:1, and the distance between the two paddles is 1 / 3 of the container height.

4. The method for preparing a novel antistatic environmentally friendly solvent-free coating according to claim 2, characterized in that: The timings of adding carbon nanotubes three times in step (2) are as follows: 50% of the total amount is added for the first time when the temperature of the base material reaches 60°C, 30% is added for the second time before the second pass of three-roller grinding, and 20% is added for the third time after the grinding is completed; different dispersion procedures are used after each addition: a dispersion disk with a diameter of Φ25 mm is used for the first time, replaced with a Φ18 mm conical disk for the second time, and a Φ30 mm flat disk for the third time.

5. The method for preparing a novel antistatic environmentally friendly solvent-free coating according to claim 2, characterized in that: The specific parameters of the pulse feeding in step (3) are: feeding frequency 2 Hz, single pulse duration 0.5 s, interval time 1.5 s, the outlet of the feeding pipe is designed as a rotatable fan-shaped nozzle, the rotation speed is linked with the feeding pump frequency and controlled at 30-60 rpm; the nano-silicon dioxide is pre-treated with plasma, the treatment power is 300 W, the time is 5 min, and a mixed gas with a volume ratio of argon to oxygen of 4:1 is introduced.

6. The method for preparing a novel antistatic environmentally friendly solvent-free coating according to claim 2, characterized in that: In step (4), the speed ratio of the planetary mixer's revolution to rotation is controlled according to a time program: 1:40 in the first 10 minutes, adjusted to 1:60 in the middle 20 minutes, and reduced to 1:30 in the last 10 minutes; 6 sets of vertical baffles are arranged on the inner wall of the mixing tank, the width of the baffles is 1 / 10 of the tank diameter, and the height is 80% of the liquid level.

7. The method for preparing a novel antistatic environmentally friendly solvent-free coating according to claim 2, characterized in that: In step (5), the ultrasonic treatment adopts a dual-frequency composite mode: 20kHz and 40kHz work alternately, each frequency acts for 5 minutes, and pauses for 30 seconds when alternating; the insertion depth of the ultrasonic probe is 2 / 3 of the liquid level, the power density is controlled at 0.5-0.8W / cm³, and the system temperature is maintained at ≤40°C during the treatment process.

8. The method for preparing a novel antistatic environmentally friendly solvent-free coating according to claim 2, characterized in that: In the step (6), the aging process adopts a dynamic temperature field: the temperature is maintained at 35°C for the first 8 hours, then increased to 38°C at a rate of 0.5°C / h for 4 hours, then decreased to 32°C at a rate of 1°C / h, and finally maintained at 34±0.5°C for 12 hours; during stirring, the blade linear speed is controlled at 0.3-0.5m / s, the stirring shaft is designed as a hollow structure, and 35°C circulating water is passed into the interior.

9. The method for preparing a novel antistatic environmentally friendly solvent-free coating according to claim 2, characterized in that: The whole process quality monitoring includes: after step (2), the fineness is tested to be ≤15μm; after step (4), the viscosity deviation is tested to be ≤±5%; after aging, the volume resistivity fluctuation range is tested to be ≤±0.5 orders of magnitude; the online detection data is uploaded to the MES system in real time, and the process parameter adjustment program is automatically triggered when any parameter exceeds the set threshold.

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