Self-suspending micropowder wax based on multiphase synergistic density regulation and its application in coating systems

Abstract

This invention discloses a self-suspended micronized wax based on multiphase synergistic density regulation and its application in coating systems. By performing affinity modification on low-density polymer phase micronized wax and grafting and coupling agent bonding modification on high-density nano-inorganic materials, the modified affinity-modified micronized wax is blended with modified inorganic functional materials to obtain a multiphase synergistic density-regulated modified micronized wax. The multiphase synergistic density-regulated modified micronized wax is then solvated, allowing the low-density polymer phase and high-density inorganic phase to form a medium-to-high density suspension in the solvent system through van der Waals forces, hydrogen bonds, and other forces, thus preparing a suspendable micronized wax. Furthermore, this suspended wax can achieve redispersion of the wax powder after slight shaking, perfectly solving the floating / sinking phenomenon of wax powder components due to insufficient suspension stability when large-capacity coatings are left to stand for long periods in the coating production line. This improves the stability of the roller coating process and the appearance quality of the coating film, and has significant industrial application value.

Description

Technical Field

[0001] This invention relates to the field of micronized wax preparation, and more particularly to self-suspended micronized wax based on multiphase synergistic density regulation and its application in coating systems. Background Technology

[0002] Micronized waxes are used in coatings as an "industrial MSG," significantly improving the feel, smoothness, scratch resistance, and abrasion resistance of coatings, thus enjoying widespread application in the coatings industry. However, due to the potential density difference between micronized waxes and coating systems, coating systems with added micronized waxes often exhibit phenomena such as the floating of low-density micronized waxes (e.g., polyethylene wax, polypropylene wax) and the settling of high-density micronized waxes (e.g., polytetrafluoroethylene wax) during actual application and storage. These floating and settling wax phenomena are common storage instability issues associated with micronized waxes in practical coating applications.

[0003] Especially during large-scale continuous roller coating production lines, a large amount of paint is stored in the paint tank to support the continuous production of the coating line. Most large-scale continuous roller coating production lines on the market currently have built-in sinking small agitators and dispersers to prevent the settling of wax powder or other pigments and fillers. However, because the pick-up roller needs to pick up the paint from the surface of the paint tank during continuous production, the relatively calm state of the liquid surface in the paint tank needs to be maintained. Therefore, the stirring power of the disperser cannot be too high. This results in the paint in the paint tank not being completely uniform. In particular, paint containing low-density, easily floating wax powder will accelerate the formation of "floating wax" phenomenon in the paint tank with relatively weak stirring. The paint containing excessive "floating wax" floating on the surface is the first to be picked up by the pick-up roller and rolled onto the substrate. This inevitably leads to uneven distribution of wax powder in the paint film during the coating process, resulting in paint film defects such as "prickly heat," "orange peel," and "pinholes."

[0004] Therefore, there is an urgent need for a technical solution that can improve or avoid the problem of floating or settling wax of micronized wax during paint storage, which leads to uneven material collection by the pick-up roller from the paint tank and causes poor paint film surface. Summary of the Invention

[0005] This invention discloses a self-suspended micronized wax based on multiphase synergistic density regulation and its application in coating systems, characterized in that: S1 low-density polymer phase fusion modification: Polytetrafluoroethylene micro powder is uniformly dispersed in low-density wax melt through a special affinity agent. The suspended melt is sprayed out by spray granulation to obtain affinity-modified wax microbeads. Then, the affinity-modified wax microbeads are pulverized by a crushing process to obtain affinity-modified micro powder wax. Modification of S2 high-density inorganic phase: Coupling agents are bonded to grafted nano-inorganic functional materials to form modified inorganic functional materials, which are used to improve the compatibility between inorganic phase and polymer phase. Preparation of S3 density-controlled suspendable micro powder wax: Low-density affinity-modified micro powder wax and high-density modified inorganic functional materials are blended and modified to obtain suspendable micro powder wax. S4 Suspended Micropowder Wax Solvation: The suspended micropowder wax is placed in a solvent system of specific polarity to complete the solvation pretreatment of the suspended micropowder wax; S5 wax paste preparation: The solubilized suspendable micro powder wax is dispersed into the wax paste base to obtain suspendable micro powder wax paste; S6 Special Coating Preparation and Application: Dispersing an appropriate amount of suspendable micro powder wax slurry into a coating system yields a special coating that can achieve the suspension effect of micro powder wax. S7 Wax Powder Suspension Effect Verification: The special coating was placed in an oven for heat storage to accelerate the simulation of the stability of wax powder in the paint tank and confirm the suspension effect of the micro powder wax. S8 Oscillation Redispersibility Verification: Apply a slight shaking force to the special coating after heat storage to verify whether the suspendable micro powder wax can be redispersed in the coating; The modified functional materials in S2 include: S21 grafting modification: surface hydroxyl or carboxyl grafting modification of nano-inorganic materials; S22 Coupling Agent Modification: Silane coupling agent is covalently bonded to the hydroxyl or carboxyl groups on the surface of the nano-inorganic functional material in S21 at 35-80℃ for 30 min-3 h to obtain coupling agent modified inorganic functional material. In S3, the preparation of suspendable micronized wax includes: blending modification of affinity-modified micronized wax and modified inorganic functional materials, with a ratio of (92-99.5):(0.5-8); In S4, the solvation of the suspendable micro powder wax includes: slowly adding the suspendable micro powder wax to a mixed solvent of ethylene glycol butyl ether (BCS), propylene glycol methyl ether (PM), dipropylene glycol butyl ether (DPNB), ethanol (EtOH), and dipropylene glycol methyl ether (DPM), heating under stirring at a temperature of 20-90℃ for 30 min-8 h.

[0006] In one embodiment, the multi-type wax powder in S1 includes polytetrafluoroethylene micro powder and low-density wax, wherein the low-density wax includes one or more combinations of polyethylene, oxidized polyethylene, polypropylene, oxidized polypropylene, Fischer-Tropsch wax, carnauba wax, candelilla wax, rice bran wax, beeswax, sunflower wax, sugarcane wax, etc.

[0007] In one embodiment, the ratio of low-density wax powder: affinity agent: polytetrafluoroethylene micro powder is (40-90):(5-10):(5-35), wherein the affinity agent includes one or more combinations of high carbon alcohols and wax esters such as methyl 4-methoxycinnamate, 4-methoxycinnamic acid, methyl p-hydroxycinnamate, and 12-hydroxy fatty acid esters.

[0008] Preferably, the low-density suspended melt containing polytetrafluoroethylene (PTFE) micropowder is heated to 100-260°C by spray granulation. After the low-density wax and affinity agent are completely melted, the PTFE micropowder is added, and the mixture is stirred continuously for 5 min to 4.5 h until the PTFE micropowder is fully dispersed in the low-density wax melt. The nozzle diameter of the spray is 1.5-7.5 mm, and the diameter of the resulting affinity-modified wax microspheres is 0.6-6 mm. The pulverization process is an air jet milling process, and the pulverized product has an affinity-modified micropowder wax with a D50 of 1-5 μm.

[0009] The addition of affinity agents can improve the compatibility and dispersibility of polytetrafluoroethylene micronized wax in low-density wax melt, ensuring the coexistence of low-density wax and polytetrafluoroethylene wax in the microparticles of the pulverized affinity-modified micronized wax.

[0010] In one embodiment, the dispersion shear velocity of the low-density wax melt is 3-15 m / s, preferably 6-10 m / s. In one embodiment, the high-density nano-inorganic material S21 is subjected to oxidation treatment and water washing treatment, wherein the mass ratio of nano-inorganic material: strong oxidant: acid solution is 10:(1.5-5):(10-50), the D50 of the nano-inorganic material is 4-8μm, and the water washing is carried out sequentially using a gradient water washing method with the pH gradually decreasing from 10 to 6.5.

[0011] The preferred nano-inorganic material: strong oxidant: acid solution mass ratio is 10:(1.8-4.5):(12-48).

[0012] Preferably, the nano-inorganic materials include one or more of the following: titanium dioxide, barium sulfate, glass powder, transparent powder, silica powder, alumina, etc.

[0013] Preferably, the strong oxidant is one or more of potassium permanganate, potassium dichromate, potassium manganate, etc.; preferably, the acid solution includes one or more of sulfuric acid, nitric acid, hydrochloric acid, or oxalic acid, benzoic acid, p-toluenesulfonic acid, acetic acid, etc., with a concentration of 30%-98%.

[0014] Preferably, the stirring linear velocity is 1-2.5 m / s; the oxidation treatment temperature is 80-100℃; and the oxidation treatment time is 30 min-6 h.

[0015] Preferably, the grafted and modified inorganic nanofunctional materials after water washing are first dried at a temperature of 75-120℃ for 2-12 hours.

[0016] Preferably, the moisture content after the first drying is 0.3-2.5%.

[0017] In one embodiment, in step S22, the silane coupling agent is sprayed onto the high-density grafted and modified nano-inorganic functional material in step S21 by spraying, and then granulated, dried and pulverized to become a modified functional material. The mass ratio of the grafted and modified nano-inorganic functional material to the solid silane coupling agent is 100:(0.5-3), preferably 100:(1-2).

[0018] In one embodiment, the granulation is achieved using a drum granulator, wherein the stirring speed of the drum granulator is 10-50 rpm, preferably 15-30 rpm, and the stirring time of the drum granulator is 10-300 min, preferably 30-60 min; the spray flow rate of the silane coupling agent in the drum granulator is 0.5-10 L / min, preferably 0.5-7.5 L / min. Preferably, the temperature of the silane coupling agent solution is 50-70℃. Under this temperature condition, the hydrolyzable group X on the silane coupling agent rapidly hydrolyzes upon contact with the heated nano-inorganic functional material to form silanol groups. The formation of silanol groups promotes the bonding of functional groups such as hydroxyl and carboxyl groups at the interface between the silane coupling agent and the nano-inorganic functional material to form strong covalent bonds. The presence of this chemical bond is beneficial to improving the compatibility between the nano-inorganic functional material and the organic polymer material.

[0019] Preferably, the silane coupling agent is one or more of vinylsilane coupling agents and acryloyloxysilane coupling agents; the mass concentration of the silane coupling agent solution is 10%-25%, preferably 12%-18%; wherein the silane coupling agent solution can be one or more of water, ethanol or methanol.

[0020] Preferably, the modified functional material needs to undergo a second drying process. The second drying temperature is 65-80℃ and the time is 1.5-8h. The second drying process can not only reduce the moisture content of the modified functional material, but also further promote the chemical bonding between the silane coupling agent and the grafted modified nano-inorganic functional material.

[0021] In one embodiment, the pulverization is air jet milling, and the D50 of the micronized coupling agent modified functional material is 1-5 μm, preferably 3-5 μm.

[0022] In one embodiment, the ratio of low-density affinity-modified micro powder wax to high-density modified functional material micro powder is preferably (92-99.5):(0.5-8), more preferably (95-98):(2-5); the two are mixed using a powder blending device, which is one of a V-type mixer, a three-dimensional mixer, or a conical mixer, with a mixing motor speed of 15-50 rpm and a blending time of 20-40 min.

[0023] In one embodiment, the mass ratio of the mixed solvent of ethylene glycol butyl ether (BCS), propylene glycol methyl ether (PM), dipropylene glycol butyl ether (DPNB), ethanol (EtOH), and dipropylene glycol methyl ether (DPM) in S4 is BCS:PM:DPNB:EtOH:DPM = (5-15):(5-25):(25-40):(5-10):(5-50), and more preferably (10-15):(10-25):(30-40):(6-8.5):(10-45).

[0024] In one embodiment, the mass ratio of the mixed solvent to the suspendable micronized wax is (55-85):(15-45), more preferably (60-80):(20-40).

[0025] In one embodiment, step S4 solubilizes the suspended micronized wax. The suspended micronized wax obtained in step S3 is rapidly dispersed in the above-mentioned mixed solvent at a linear velocity of 2-5 m / s. After stirring, the temperature is increased to 40-80°C while stirring. After maintaining the temperature, the linear velocity is reduced to 0.2-1.5 m / s and stirring continues for 20-60 min. The increase in temperature in this process is beneficial to improving the bonding strength between the silanol groups on the silane coupling agent and the grafted modified nano-inorganic functional material. The decrease in stirring linear velocity is beneficial to promoting the effective adsorption of the lipophilic groups modified by the coupling agent and the low-density wax on the surface of the affinity-modified micronized wax, so that the suspended micronized wax forms a relatively stable whole at the microscopic level. Then, the solid-liquid mixture is separated by centrifugation to obtain a well-solventized, integrally stable, wet suspended micronized wax.

[0026] In one embodiment, in step S5, the wax paste is prepared into a mixing system, the mixing system comprising wax paste resin, wax paste additives and wax paste solvent, wherein the ratio of the mixing system to the suspendable wax powder is (60-90):(10-40).

[0027] In one embodiment, the mixed system includes wax resin, PM, BCS, and defoamer, with a mass ratio of (20-50):(5-35):(5-50):(0.2-0.8), preferably (20-45):(10-30):(10-45):(0.3-0.6), and the wax resin is one of benzo-melamine resin, methyl etherified high-imino resin, and melamine-formaldehyde resin.

[0028] Secondly, this invention discloses the application, thermal storage suspension and vibration redispersion verification of a special coating containing suspendable micronized wax. Specifically, the suspendable micronized wax slurry is added to the varnish and dispersed.

[0029] The varnish is a water-based or solvent-based coating system, which includes a main resin, curing agent, neutralizer, solvent, film-forming aid, defoamer, wetting and leveling agent, etc., with a mass ratio of (30-50):(7-14):(1-4):(1-14):(15-30):(0.2-0.6):(0.2-0.6).

[0030] In one embodiment, the ratio of varnish to suspendable micronized wax slurry is (90-97.5):(2.5-10), preferably (92-96):(4-8).

[0031] In one embodiment, a heat storage verification experiment was conducted on the suspendable special coating. The method is characterized by sealing the coating containing suspendable micro powder wax in a transparent plastic bottle and then placing it in an oven for heat storage, observing the state of the wax powder in the coating, and verifying the suspension application of the suspendable micro powder wax in the coating.

[0032] Preferably, the temperature of the heat storage oven is 25-70℃ and the heat storage time is 1-90 days, more preferably 35-60℃ and 7-30 days.

[0033] In one embodiment, a vibration redispersion verification test is conducted on the special coating after heat storage. The characteristic is that the above-mentioned suspendable special coating is placed on a vibrator to verify whether the suspendable micro powdered wax can be redisperded. The vibration parameters of the vibrator are 10-200 rpm and 5-300 s, preferably 80-150 rpm and 10-60 s.

[0034] This invention discloses a self-suspending micronized wax based on multiphase synergistic density regulation and its application in coating systems. By affinity modification of low-density polymeric micronized wax and grafting and coupling agent bonding of high-density nano-inorganic materials, the modified affinity-modified micronized wax is blended with modified inorganic functional materials to obtain a multiphase synergistic density-regulated modified micronized wax. This multiphase synergistic density-regulated modified micronized wax is then solvated to prepare a suspendable micronized wax. This method effectively solves a technical problem in large-scale continuous roller coating processes: the floating / sinking phenomenon of wax powder components due to insufficient suspension stability when large volumes of coating are left to stand in the storage tank for a long time. Through innovative multiphase synergistic density regulation technology, it ensures that the coating transferred from the feeding roller to the substrate surface maintains a uniform wax powder distribution, avoiding fluctuations in wax powder content and eliminating paint film defects caused by uneven wax powder dispersion, including but not limited to surface defects such as "prickly heat," "orange peel," and "pinholes." This technical solution significantly improves the stability of the roller coating process and the appearance quality of the coating film, and has important industrial application value.

[0035] This invention also provides a method for verifying the suspension effect of suspendable special coatings, which verifies the stability of suspendable micro powder wax through thermal storage; In addition, the present invention provides a verification test to verify whether suspended wax micropowder in suspendable special coatings can be redispersed after low-frequency oscillation. Attached Figure Description

[0036] Figure 1 This is a photograph of the suspended wax powder described in Example 1 of the present invention suspended in a coating system at 55°C for 7 days. Figure 2 This is a photograph of the suspended wax powder described in Example 2 of the present invention after being stored at 55°C for 7 days in a coating system. Figure 3 This is a photograph of the inorganic modified micronized wax described in Comparative Example 1 of the present invention floating in a coating system after being heated at 55°C for 7 days. Figure 4 This is a photograph of the inorganic modified micronized wax described in Comparative Example 2 of the present invention floating in a coating system after being heated at 55°C for 7 days; Figure 5 This is a photograph showing the floating and settling of the inorganic modified micronized wax described in Comparative Example 3 of the present invention after being heat-stored at 55°C for 7 days in a coating system. Figure 6 This is a photograph of the inorganic modified micronized wax described in Comparative Example 4 of the present invention floating in a coating system after being heated at 55°C for 7 days.

[0037] Figure 7 This is a schematic diagram of the redispersion of micronized wax after heat storage and vibration as described in Embodiments 1 & 2 of the present invention. Detailed Implementation

[0038] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described below. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of the invention. Example 1

[0039] The S1 low-density polymer phase was melt-modified to obtain affinity-modified micronized wax. In the melt spray granulation system, 425 kg of oxidized polyethylene wax, carnauba wax, and beeswax in a mass ratio of 5:3:2 are first heated and melted in a melting tank at 125°C with a stirring speed of 8 m / s. While maintaining a constant stirring speed, 25 kg of affinity agent methyl 4-methoxycinnamate is slowly added. After stirring for 30 minutes to ensure complete dissolution and dispersion of methyl 4-methoxycinnamate in the mixed low-density wax melt, 50 kg of D50=1.8 μm polytetrafluoroethylene micropowder wax is slowly added. After continuous stirring for 60 minutes, a uniformly dispersed suspended high-temperature melt is obtained. This suspended high-temperature melt is then transported by a material transfer pump to the nozzle of a 3 mm diameter spray granulation tower for spraying, resulting in affinity-modified wax microspheres with a diameter of 1.2 mm. These microspheres are then pulverized using air jet milling to achieve a D10=2.9 μm diameter. The affinity-modified micronized wax with D50=4.5μm and D90=6.5μm, the addition of affinity agent can significantly improve the compatibility and dispersion uniformity of polytetrafluoroethylene micronized wax in low-density wax melt, and ensure the uniform blending of low-density wax and polytetrafluoroethylene wax in the pulverized affinity-modified micronized wax particles.

[0040] Modification of the high-density inorganic phase S2 yields modified inorganic functional materials. S21 Grafting Modification: Specifically, 60 kg of alumina and 40 kg of titanium dioxide nanomaterials were added to 400 kg of an acid solution containing 20 kg of potassium permanganate. The acid solution consisted of 230 kg of a 70% p-toluenesulfonic acid aqueous solution and 170 kg of a 40% sulfuric acid aqueous solution. The mixture was dispersed at a shear rate of 2.5 m / s to ensure the uniform formation of hydroxyl and / or carboxyl functional groups on the surface of the inorganic nanomaterials. After reflux at 90°C for 1 hour, surface-grafted modified alumina / titanium oxide was obtained. The reaction system was then separated into solid and liquid phases using a centrifuge to obtain the acid-containing grafted modified alumina / titanium oxide. Alumina / titanium oxide; then a water washing process is performed: 100KG of the above grafted modified alumina / titanium oxide is washed with 200KG of sodium hydroxide aqueous solution with pH=10, 150KG of sodium bicarbonate aqueous solution with pH=8, and 300KG of deionized water with pH=6.8, respectively. The deionized water washing is performed 3 times to obtain a wet material of surface grafted modified alumina / titanium oxide with pH close to 7. Then it is transferred to a high-temperature furnace for a high-temperature drying process, wherein the heating temperature is 95℃ and the heating time is up to 3h, to obtain alumina / titanium oxide powder with a water content of 1.7% and surface -OH and -COOH. S22 Coupling Agent Bonding: In the coupling agent modification process, the alumina / titanium oxide powder obtained in S21 is rapidly transferred to a drum granulator with a stirring speed of 25 rpm. 10 kg of an ethanol solution of vinyltrimethoxysilane A-171 at 65°C and a volume concentration of 14% is sprayed onto the surface of 100 kg of continuously stirred alumina / titanium oxide powder at a spray flow rate of 1.05 L / min. After spraying, stirring continues. The silanol groups after A-171 hydrolysis form strong covalent chemical bonds with the alumina / titanium oxide interface. The presence of this chemical bond is beneficial for improving the alumina / titanium oxide... The compatibility of titanium dioxide with organic polymer materials ensures that alumina / titanium dioxide powder can be readily blended with polymer materials such as low-density wax micropowder to obtain silane coupling agent modified alumina / titanium dioxide. This modified alumina / titanium dioxide is then transferred to a 70°C oven for secondary high-temperature drying for 3 hours. This high-temperature treatment not only reduces the moisture content of the alumina / titanium dioxide but also promotes the full chemical bonding between A-171 and the alumina / titanium dioxide. The modified alumina / titanium dioxide is then pulverized in an air jet mill to obtain silane coupling agent modified nano-inorganic functional material alumina / titanium dioxide micropowder with D10=1.2μm, D50=4.3μm, and D90=6.4μm.

[0041] Preparation of S3 density-controlled suspendable micro powder wax: The low-density affinity-modified micro powder wax obtained from S1 and the high-density coupling agent-modified alumina / titanium oxide micro powder obtained from S2 were added to a V-type mixer at a mass ratio of 95:5 for blending modification to obtain suspendable micro powder wax. The mixing motor speed was 40 rpm and the mixing time was 30 min.

[0042] S4 Suspended Micropowder Wax Solvation: To solvate the suspended micropowder wax, first mix 10 parts of ethylene glycol butyl ether (BCS), 15 parts of propylene glycol methyl ether (PM), 40 parts of dipropylene glycol butyl ether (DPNB), 7 parts of ethanol (EtOH), and 35 parts of dipropylene glycol methyl ether (DPM) in a reactor to obtain 60 kg of a mixed solvent with a specific polarity. Then, slowly add 40 kg of the suspended micropowder wax obtained in S3 into the above reactor for solvation treatment. Specifically, the suspendable micronized wax powder is first uniformly dispersed in a mixed solvent under a relatively high stirring speed of 2.3 m / s. Then, the reaction system is heated to 75°C, the stirring speed is reduced to 0.5 m / s, and the temperature is maintained for 45 min to obtain the solvated suspendable micronized wax powder. The increase in temperature during this process is beneficial to improving the bonding strength between the silanol groups on the silane coupling agent and the alumina / titanium oxide. The decrease in stirring speed can promote the effective adsorption of the lipophilic groups modified by the coupling agent and the low-density wax on the surface of the affinity-modified micronized wax powder, so that the suspendable micronized wax powder forms a relatively stable whole at the microscopic level. Then, the solid-liquid mixture is separated by centrifugation to obtain a well-solventized, overall stable, wet, multiphase synergistic density-controlled suspendable micronized wax powder.

[0043] Preparation of S5 wax slurry: First, the solid content of the wet suspended micronized wax obtained from S4 was weighed and calculated to be 65.36%. Second, the wax slurry carrier was prepared by accurately weighing 40 parts of Cymel 659 phenyl melamine resin, 25 parts of PM, 34.5 parts of BCS, and 0.5 parts of BL-B508W defoamer into a reactor and dispersing them evenly using a high-speed disperser to obtain 278KG of wax slurry carrier. Then, 122kg of wet suspended micronized wax (actual dry wax powder about 80KG) was slowly added to the above wax slurry carrier and dispersed evenly at high speed to obtain 400KG of suspended wax slurry with a wax powder content of about 20%.

[0044] S6 Special Coating Preparation and Application: Preparation of Special Coatings Containing Suspended Micronized Wax. First, a clear varnish coating is prepared by mixing 39 parts of the main resin BL-R312W, 9 parts of curing agent Cymel 659, 2.8 parts of neutralizing agent DMEA, 3.8 parts of solvent BCS, 20 parts of film-forming aid PM, 0.3 parts of defoamer BL-B508W, and 0.4 parts of wetting and leveling agent BL-G500W until homogeneous. Then, under stirring conditions in a high-speed disperser, 4 parts of the suspended wax slurry described in S5 are added to 96 parts of the clear varnish coating and dispersed evenly to obtain a special clear varnish coating containing suspended wax.

[0045] S7 special coating heat storage was used to verify the suspension effect: 60g of S6 varnish coating containing suspendable micro powder wax was sealed in a transparent plastic bottle and then placed in a 55℃ oven for heat storage for 7 days to observe the state of the suspendable micro powder wax in the coating.

[0046] S8 Oscillation Redispersibility Verification: The special coating obtained in S7 was subjected to a slight shaking force using an oscillator at 100 rpm for 15 seconds to verify whether the suspendable micro powder wax could be redispersed in the coating. Comparative Example 1: No affinity agent added

[0047] The fusion modification of the low-density polymer phase S1 yielded fluorine-modified micronized wax: In the melt spray granulation system, 425 kg of oxidized polyethylene wax, carnauba wax, and beeswax in a mass ratio of 5:3:2 are first heated and melted in a melting tank at 125°C with a stirring speed of 8 m / s. While maintaining a constant stirring speed, 50 kg of polytetrafluoroethylene micro powder wax with a D50 of 1.83 μm is slowly added. After continuous stirring for 60 minutes, a uniformly dispersed suspended high-temperature melt is obtained. The suspended high-temperature melt is then transported to the nozzle of a spray granulation tower with a diameter of 3 mm by a material transfer pump and sprayed out to obtain fluorinated wax microspheres with a diameter of 1.8 mm. The microspheres are then pulverized by air jet milling into fluorinated micro powder wax with D10 = 2.85 μm, D50 = 4.52 μm, and D90 = 6.49 μm.

[0048] Modification of the high-density inorganic phase S2 yields modified inorganic functional materials. S21 Grafting Modification: Specifically, 60 kg of alumina and 40 kg of titanium dioxide nanomaterials were added to a 400 kg acid solution containing 20 kg of potassium permanganate. The 400 kg acid solution consisted of 230 kg of 70% p-toluenesulfonic acid aqueous solution and 170 kg of 40% sulfuric acid aqueous solution. The mixture was dispersed at a shear rate of 2.5 m / s to ensure uniform formation of hydroxyl and / or carboxyl functional groups on the surface of the inorganic nanomaterials. After reflux at 90°C for 1 hour, surface-grafted modified alumina / titanium oxide was obtained. The reaction system was then separated into solid and liquid phases using a centrifuge to obtain the acid-containing grafted modified alumina / titanium oxide. The grafted alumina / titanium oxide is then subjected to a water washing process: 100KG of the above grafted alumina / titanium oxide is washed with 200KG of sodium hydroxide aqueous solution with pH=10, 150KG of sodium bicarbonate aqueous solution with pH=8, and 300KG of deionized water with pH=6.8, respectively. The deionized water washing is performed 3 times to obtain a wet material of grafted alumina / titanium oxide with pH close to 7. Then it is transferred to a high-temperature furnace for a high-temperature drying process, wherein the heating temperature is 95℃ and the heating time is up to 3h, to obtain alumina / titanium oxide powder with a water content of 1.7% and a surface with -OH and -COOH. S22 Coupling Agent Bonding: In the coupling agent modification process, the alumina / titanium oxide powder obtained in S21 is rapidly transferred to a drum granulator with a stirring speed of 25 rpm. 10 kg of an ethanol solution of vinyltrimethoxysilane A-171 at 65°C and a volume concentration of 14% is sprayed onto the surface of 100 kg of continuously stirred alumina / titanium oxide powder at a spray flow rate of 1.05 L / min. After spraying, stirring continues. The silanol groups after A-171 hydrolysis form strong covalent chemical bonds with the alumina / titanium oxide interface. The presence of this chemical bond is beneficial for improving the alumina / titanium oxide... The compatibility of titanium dioxide with organic polymer materials ensures that alumina / titanium oxide powder can be readily blended with polymer materials such as low-density wax micropowder to obtain silane coupling agent modified alumina / titanium oxide. This modified alumina / titanium oxide is then transferred to a 70°C oven for secondary high-temperature drying for 3 hours. This high-temperature treatment not only reduces the moisture content of the alumina / titanium oxide but also promotes the full chemical bonding between A-171 and the alumina / titanium oxide. The modified alumina / titanium oxide is then pulverized in an air jet mill to obtain silane coupling agent modified nano-inorganic functional material alumina / titanium oxide micropowder with D10=1.22μm, D50=4.31μm, and D90=6.34μm.

[0049] Preparation of S3 density-controlled modified micro powder wax: The fluorine-modified micro powder wax obtained from S1 and the coupling agent-modified alumina / titanium oxide micro powder obtained from S2 were added to a V-type mixer at a mass ratio of 95:5 for blending and modification to obtain density-controlled modified micro powder wax. The mixing motor speed was 40 rpm and the mixing time was 30 min.

[0050] S4 Density-Controlled Modified Micronized Wax Solvation: The micronized wax described in S3 is solvated by first mixing 10 parts of ethylene glycol butyl ether (BCS), 15 parts of propylene glycol methyl ether (PM), 40 parts of dipropylene glycol butyl ether (DPNB), 7 parts of ethanol (EtOH), and 35 parts of dipropylene glycol methyl ether (DPM) in a reaction vessel to obtain 60 kg of a mixed solvent with a special polarity. Then, 40 kg of the micronized wax obtained in S3 is slowly added to the above reaction vessel for solvation treatment. Specifically, the modified micronized wax powder was first uniformly dispersed in a mixed solvent at a relatively high stirring speed of 2.3 m / s. Then, the reaction system was heated to 75°C, the stirring speed was reduced to 0.5 m / s, and the temperature was maintained for 45 min to obtain the solvated modified micronized wax powder. The increase in temperature during this process is beneficial to improving the bonding strength between the silanol groups on the silane coupling agent and the alumina / titanium oxide. The decrease in stirring speed can promote the effective adsorption of the lipophilic groups modified by the coupling agent and the low-density wax on the surface of the fluorinated micronized wax powder, so that the modified micronized wax powder obtained in S3 forms a relatively stable whole at the microscopic level. Then, the solid-liquid mixture was separated by centrifugation to obtain a well-solventized, overall stable wet modified micronized wax powder.

[0051] Preparation of S5 wax slurry: First, the solid content of the wet modified micronized wax obtained from S4 was weighed and calculated to be 65.48%. Second, the wax slurry carrier was prepared by accurately weighing 40 parts of Cymel 659 phenyl melamine resin, 25 parts of PM, 34.5 parts of BCS, and 0.5 parts of BL-B508W defoamer into a reactor. After uniform dispersion using a high-speed disperser, 278.3 kg of wax slurry carrier was obtained. Then, 122 kg of wet modified micronized wax (actual dry wax powder of about 80 kg) was slowly added to the above wax slurry carrier and uniformly dispersed at high speed to obtain 400 kg of modified micronized wax slurry with a wax powder content of about 20%.

[0052] S6 Coating Preparation and Application: Preparation of Coatings Containing Modified Micronized Wax. First, a clear varnish coating was prepared by mixing 39 parts of the main resin BL-R312W, 9 parts of curing agent Cymel 659, 2.8 parts of neutralizing agent DMEA, 3.8 parts of solvent BCS, 20 parts of film-forming aid PM, 0.3 parts of defoamer BL-B508W, and 0.4 parts of wetting and leveling agent BL-G500W until homogeneous. Then, under stirring conditions in a high-speed disperser, 4 parts of the wax slurry described in S5 were added to 96 parts of the clear varnish coating and dispersed until homogeneous to obtain a coating containing modified micronized wax.

[0053] S7 coating heat storage was used to verify the suspension effect. About 60g of the coating varnish containing modified micro powder wax obtained from S6 was sealed in a transparent plastic bottle and then placed in a 55℃ oven for heat storage for 7 days to observe the state of the wax micro powder in the coating. Comparative Example 2: Inorganic nanomaterials without acid treatment

[0054] The S1 low-density polymer phase was melt-modified to obtain affinity-modified micronized wax. In the melt spray granulation system, 425 kg of oxidized polyethylene wax, carnauba wax, and beeswax in a mass ratio of 5:3:2 are first heated and melted in a melting tank at 125°C with a stirring speed of 8 m / s. While maintaining a constant stirring speed, 25 kg of affinity agent methyl 4-methoxycinnamate is slowly added. After stirring for 30 minutes to ensure complete dissolution and dispersion of methyl 4-methoxycinnamate in the mixed low-density wax melt, 50 kg of D50=1.75 μm polytetrafluoroethylene micropowder wax is slowly added. After continuous stirring for 60 minutes, a uniformly dispersed suspended high-temperature melt is obtained. This suspended high-temperature melt is then transported by a material transfer pump to the nozzle of a 3 mm diameter spray granulation tower for spraying, resulting in affinity-modified wax microspheres with a diameter of 1.1 mm. These microspheres are then pulverized using airflow milling to achieve a D10=2.85 μm diameter. The affinity-modified micronized wax with D50=4.45μm and D90=6.51μm, the addition of affinity agent can greatly improve the compatibility and dispersion uniformity of polytetrafluoroethylene micronized wax in low-density wax melt, and ensure the uniform blending of low-density wax and polytetrafluoroethylene wax in the pulverized affinity-modified micronized wax particles.

[0055] S2 modified functional materials: S21 Coupling Agent Bonding: Preparation of Silane Coupling Agent Modified Nano-Inorganic Functional Material Powder. Specifically, 60 kg of alumina and 40 kg of titanium dioxide nano-inorganic materials were transferred to a drum granulator with a stirring speed of 25 rpm. After stirring for a period of time to ensure that the alumina and titanium dioxide were fully mixed, 5 kg of deionized water was sprayed onto the surface of 100 kg of continuously stirred alumina / titanium dioxide powder at a spray flow rate of 500 mL / min. Then, it was transferred to an 80℃ hot air oven and baked for 30 min to obtain alumina / titanium dioxide granulated powder with a moisture content of 1.7%. The obtained wet alumina / titanium dioxide granulated powder was quickly transferred to a drum granulator with a stirring speed of 25 rpm. 10 kg of an ethanol solution of vinyltrimethoxysilane A-171 at a temperature of 65℃ and a volume concentration of 14% was sprayed onto the continuously stirred 100 kg of alumina / titanium dioxide powder. The surface of titanium dioxide powder was sprayed with a flow rate of 1.05 L / min. After spraying, the mixture was continuously stirred. The silanol groups after hydrolysis of A-171 may potentially form relatively reliable covalent chemical bonds with the alumina / titanium dioxide interface. The presence of this chemical bond is beneficial to improving the compatibility of alumina / titanium dioxide with organic polymer materials, ensuring that the alumina / titanium dioxide powder can be readily blended with polymer materials such as low-density wax micropowder, resulting in silane coupling agent modified alumina / titanium dioxide. This modified alumina / titanium dioxide was then transferred to a 70°C oven for secondary high-temperature drying for 3 hours. This high-temperature treatment not only reduces the moisture content of the alumina / titanium dioxide but also promotes sufficient chemical bonding between A-171 and the alumina / titanium dioxide. Finally, the modified alumina / titanium dioxide was transferred to an air jet mill for pulverization, yielding a D10 of 1.22 μm. Silane coupling agent modified alumina / titanium dioxide micropowder with D50=4.33μm and D90=6.28μm.

[0056] Preparation of S3 density-controlled modified micro powder wax: The affinity-modified micro powder wax obtained from S1 and the untreated coupling agent-modified alumina / titanium dioxide micro powder from S2 were added to a V-type mixer at a mass ratio of 95:5 for blending modification to obtain modified micro powder wax. The mixing motor speed was 40 rpm and the mixing time was 30 min.

[0057] S4 Modified Micronized Wax Solvation: The modified micronized wax obtained in S3 is solvated by first mixing 10 parts of ethylene glycol butyl ether (BCS), 15 parts of propylene glycol methyl ether (PM), 40 parts of dipropylene glycol butyl ether (DPNB), 7 parts of ethanol (EtOH), and 35 parts of dipropylene glycol methyl ether (DPM) in a reaction vessel to obtain 60 kg of a mixed solvent with a special polarity. Then, 40 kg of the modified micronized wax obtained in S3 is slowly added to the above reaction vessel for solvation treatment. Specifically, the modified micronized wax powder is first uniformly dispersed in a mixed solvent at a relatively high stirring speed of 2.3 m / s. Then, the reaction system is heated to 75°C, the stirring speed is reduced to 0.5 m / s, and the temperature is maintained for 45 min to obtain the solvated modified micronized wax powder. The increase in temperature during this process is beneficial to improving the bonding strength between the silanol groups on the silane coupling agent and the alumina / titanium dioxide. The decrease in stirring speed can promote the effective adsorption of the lipophilic groups of the coupling agent and the low-density wax on the surface of the affinity-modified micronized wax powder, so that the modified micronized wax powder forms a relatively stable whole at the microscopic level. Then, the solid-liquid mixture is separated by centrifugation to obtain a well-solventized, overall stable wet modified micronized wax powder.

[0058] Preparation of S5 wax slurry: First, the solid content of the wet modified micronized wax obtained from S4 was weighed and calculated to be 65.18%. Second, the wax slurry carrier was prepared by accurately weighing 40 parts of Cymel 659 phenyl melamine resin, 25 parts of PM, 34.5 parts of BCS, and 0.5 parts of BL-B508W defoamer into a reactor and dispersing them evenly using a high-speed disperser to obtain 278 kg of wax slurry carrier. Then, 122 kg of wet modified micronized wax (actual dry wax powder about 80 kg) was slowly added to the above wax slurry carrier and dispersed evenly at high speed to obtain about 400 kg of modified wax slurry with a wax powder content of about 20%.

[0059] S6 Coating Preparation and Application: Preparation of Coatings Containing Modified Micronized Wax. First, a clear varnish coating is prepared by mixing 39 parts of the main resin BL-R312W, 9 parts of curing agent Cymel 659, 2.8 parts of neutralizing agent DMEA, 3.8 parts of solvent BCS, 20 parts of film-forming aid PM, 0.3 parts of defoamer BL-B508W, and 0.4 parts of wetting and leveling agent BL-G500W until homogeneous. Then, under stirring conditions in a high-speed disperser, 4 parts of the wax slurry described in S5 are added to 96 parts of the clear varnish coating and dispersed until homogeneous to obtain the final clear varnish coating.

[0060] S7 coating heat storage was used to verify the suspension effect. 60g of the varnish coating containing modified micronized wax obtained from S6 was sealed in a transparent plastic bottle and then placed in a 55℃ oven for heat storage for 7 days to observe the state of the suspendable micronized wax in the coating. Comparative Example 3: Treatment of Inorganic Nanomaterials Without Coupling Agents

[0061] The S1 low-density polymer phase was melt-modified to obtain affinity-modified micronized wax. In the melt spray granulation system, 425 kg of a mixture of oxidized polyethylene wax, carnauba wax, and beeswax in a mass ratio of 5:3:2 is first melted and stirred uniformly in a melting tank at 125°C with a stirring speed of 8 m / s. While maintaining a constant stirring speed, 25 kg of the affinity agent methyl 4-methoxycinnamate is slowly added. After stirring for 30 minutes to ensure complete dissolution and dispersion of methyl 4-methoxycinnamate in the mixed low-density wax melt, 50 kg of polytetrafluoroethylene (PTFE) micro-powder wax with a D50 of 1.88 μm is slowly added. After continuous stirring for 60 minutes, a uniformly dispersed suspended high-temperature melt is obtained. This suspended high-temperature melt is then transported by a material transfer pump to the nozzle of a spray granulation tower with a nozzle diameter of 3 mm and sprayed out to obtain affinity-modified wax microspheres with a diameter of 1.28 mm. These microspheres are then pulverized using airflow milling to achieve a D10 of 2.76 μm. The affinity-modified micronized wax with D50=4.38μm and D90=6.49μm, the addition of affinity agent can greatly improve the compatibility and dispersion uniformity of polytetrafluoroethylene micronized wax in low-density wax melt, and ensure the uniform blending of low-density wax and polytetrafluoroethylene wax in the pulverized affinity-modified micronized wax particles.

[0062] Modification of the high-density inorganic phase of S2 yields graft-modified inorganic functional materials. S21 Grafting Modification: Surface oxidation grafting modification of nano-inorganic materials. Specifically, 60 kg of alumina and 40 kg of titanium dioxide nano-inorganic materials were added to 400 kg of acid solution containing 20 kg of potassium permanganate. The 400 kg acid solution consisted of 230 kg of 70% p-toluenesulfonic acid aqueous solution and 170 kg of 40% sulfuric acid aqueous solution. The mixture was dispersed at a shear rate of 2.5 m / s to ensure uniform formation of hydroxyl and / or carboxyl functional groups on the surface of the inorganic nano-functional materials. After reflux at 90°C for 1 h, surface-grafted modified alumina / titanium dioxide was obtained. The reaction system was then separated into solid and liquid phases using a centrifuge to obtain acid-containing grafted modified alumina / titanium dioxide. Then, water... Washing process: 100KG of the above-mentioned grafted modified alumina / titanium dioxide was washed with 200KG of sodium hydroxide aqueous solution with pH=10, 150KG of sodium bicarbonate aqueous solution with pH=8, and 300KG of deionized water with pH=6.8, respectively. The deionized water washing was performed 3 times to obtain a wet material of surface grafted modified alumina / titanium dioxide with pH close to 7. Then, it was transferred to a high-temperature furnace for a high-temperature drying process, in which the heating temperature was 95℃ and the heating time was up to 4h, to obtain modified alumina / titanium dioxide powder with a water content of less than 0.1% and a surface with -OH and -COOH. Then, the above-mentioned modified alumina / titanium dioxide was transferred to an air jet mill for pulverization to obtain grafted modified nano-inorganic functional material alumina / titanium dioxide micro powder with D10=1.21μm, D50=4.29μm, and D90=6.36μm.

[0063] Preparation of S3 density-controlled modified micro powder wax: The affinity-modified micro powder wax obtained from S1 and the nano-alumina / titanium dioxide functional micro powder obtained from S2 were added to a V-type mixer at a mass ratio of 95:5 for blending and modification to obtain modified micro powder wax. The mixing motor speed was 40 rpm and the mixing time was 30 min.

[0064] S4 Modified Micronized Wax Solvation: To solvate the modified micronized wax, first, 10 parts of ethylene glycol butyl ether (BCS), 15 parts of propylene glycol methyl ether (PM), 40 parts of dipropylene glycol butyl ether (DPNB), 7 parts of ethanol (EtOH), and 35 parts of dipropylene glycol methyl ether (DPM) are stirred and mixed evenly in a reaction vessel to obtain 60KG of a mixed solvent with a special polarity. Then, 40KG of the modified micronized wax obtained from S3 is slowly added to the above reaction vessel for solvation treatment. Specifically, the modified micronized wax powder is first uniformly dispersed in a mixed solvent at a relatively high stirring speed of 2.3 m / s. Then, the reaction system is heated to 75°C, the stirring speed is reduced to 0.5 m / s, and the temperature is maintained for 45 min to obtain the solvated modified micronized wax powder. This process allows the modified micronized wax powder to form a relatively stable whole at the microscopic level. Then, the solid-liquid mixture is separated by centrifugation to obtain a well-solventized, stable, wet modified micronized wax powder.

[0065] Preparation of S5 wax slurry: First, the solid content of the wet modified micronized wax obtained from S4 was weighed and calculated to be 65.75%. Second, the wax slurry carrier was prepared by accurately weighing 40 parts of Cymel 659 styrene melamine resin, 25 parts of PM, 34.5 parts of BCS, and 0.5 parts of BL-B508W defoamer into a reactor and dispersing them evenly using a high-speed disperser to obtain 278KG of wax slurry carrier. The dispersion speed was then reduced, and 122kg of wet modified wax powder (actual dry wax powder about 80KG) was slowly added to the above wax slurry carrier and dispersed evenly at high speed to obtain about 400KG of modified wax slurry with a wax powder content of about 20%.

[0066] Preparation and Application of S6 Clear Varnish Coating: Preparation of Coating Containing Modified Micronized Wax. First, prepare the clear varnish coating by mixing 39 parts of the main resin BL-R312W, 9 parts of curing agent Cymel 659, 2.8 parts of neutralizing agent DMEA, 3.8 parts of solvent BCS, 20 parts of film-forming aid PM, 0.3 parts of defoamer BL-B508W, and 0.4 parts of wetting and leveling agent BL-G500W until homogeneous. Then, under stirring conditions in a high-speed disperser, add 4 parts of the wax slurry described in S5 to 96 parts of the clear varnish coating and disperse until homogeneous to obtain the clear varnish coating containing modified wax micronized powder.

[0067] S7 coating heat storage was used to verify the suspension effect. 60g of the varnish coating containing modified wax obtained from S6 was sealed in a transparent plastic bottle and then placed in a 55℃ oven for heat storage for 7 days to observe the state of the wax powder in the coating. Comparative Example 4: Modified micronized wax without solvation treatment

[0068] The S1 low-density polymer phase was melt-modified to obtain affinity-modified micronized wax. In the melt spray granulation system, 425 kg of a mixture of oxidized polyethylene wax, carnauba wax, and beeswax in a mass ratio of 5:3:2 is first melted and stirred uniformly in a melting tank at 125°C with a stirring speed of 8 m / s. While maintaining a constant stirring speed, 25 kg of the affinity agent methyl 4-methoxycinnamate is slowly added. After stirring for 30 minutes to ensure complete dissolution and dispersion of methyl 4-methoxycinnamate in the mixed low-density wax melt, 50 kg of polytetrafluoroethylene (PTFE) micro-powder wax with a D50 of 1.8 μm is slowly added. After continuous stirring for 60 minutes, a uniformly dispersed suspended high-temperature melt is obtained. This suspended high-temperature melt is then pumped to a 3 mm diameter spray granulation tower nozzle for spraying, resulting in affinity-modified wax microspheres with a diameter of 1.25 mm. These microspheres are then pulverized using air jet milling to achieve a D10 of 2.76 μm. The affinity-modified micronized wax with D50=4.38μm and D90=6.72μm, the addition of affinity agent can significantly improve the compatibility and dispersion uniformity of polytetrafluoroethylene micronized wax in low-density wax melt, and ensure the uniform blending of low-density wax and polytetrafluoroethylene wax in the pulverized affinity-modified micronized wax particles.

[0069] Modification of the high-density inorganic phase S2 yields modified inorganic functional materials. S21 Grafting Modification: Specifically, 60 kg of alumina and 40 kg of titanium dioxide nanomaterials were added to 400 kg of an acid solution containing 20 kg of potassium permanganate. The acid solution consisted of 230 kg of a 70% p-toluenesulfonic acid aqueous solution and 170 kg of a 40% sulfuric acid aqueous solution. The mixture was dispersed at a shear rate of 2.5 m / s to ensure uniform formation of hydroxyl and / or carboxyl functional groups on the surface of the inorganic nanomaterials. After reflux at 90°C for 1 hour, surface-grafted alumina / titanium oxide was obtained. The reaction system was then separated into solid and liquid phases using a centrifuge to obtain acid-containing grafted alumina / titanium oxide. Alumina / titanium oxide; then a water washing process is performed: 100KG of the above-mentioned grafted modified alumina / titanium oxide is washed with 200KG of sodium hydroxide aqueous solution with pH=10, 150KG of sodium bicarbonate aqueous solution with pH=8 and 300KG of deionized water with pH=6.8 respectively, and the deionized water washing is performed 3 times to obtain a wet material of surface grafted modified alumina / titanium oxide with pH close to 7. Then it is transferred to a high-temperature furnace for a high-temperature drying process, where the heating temperature is 95℃ and the heating time is up to 3h, to obtain alumina / titanium oxide powder with -OH and -COOH on the surface with a water content of 1.7%; S22 Coupling Agent Bonding: In the coupling agent modification process, the alumina / titanium oxide powder obtained in S21 is rapidly transferred to a drum granulator with a stirring speed of 25 rpm. 10 kg of an ethanol solution of vinyltrimethoxysilane A-171 at 65°C and a volume concentration of 14% is sprayed onto the surface of 100 kg of continuously stirred alumina / titanium oxide powder at a spray flow rate of 1.05 L / min. After spraying, stirring continues. The silanol groups after A-171 hydrolysis form strong covalent chemical bonds with the alumina / titanium oxide interface. The presence of this chemical bond is beneficial for improving the alumina / titanium oxide... The compatibility of titanium dioxide with organic polymer materials ensures that alumina / titanium oxide powder can be readily blended with polymer materials such as low-density wax micropowder to obtain silane coupling agent modified alumina / titanium oxide. This modified alumina / titanium oxide is then transferred to a 70°C oven for secondary high-temperature drying for 3 hours. This high-temperature treatment not only reduces the moisture content of the alumina / titanium oxide but also promotes the full chemical bonding between A-171 and the alumina / titanium oxide. The modified alumina / titanium oxide is then pulverized in an air jet mill to obtain silane coupling agent modified nano-inorganic functional material alumina / titanium oxide micropowder with D10=1.22μm, D50=4.33μm, and D90=6.44μm.

[0070] Preparation of S3 density-controlled suspendable micro powder wax: The low-density affinity-modified micro powder wax obtained from S1 and the high-density coupling agent-modified alumina / titanium oxide micro powder obtained from S2 were added to a V-type mixer at a mass ratio of 95:5 for blending modification to obtain suspendable micro powder wax. The mixing motor speed was 40 rpm and the mixing time was 30 min.

[0071] Preparation of S4 wax slurry: First, the solid content of the wet suspended micronized wax obtained from S4 was weighed and calculated to be 65.33%. Second, the wax slurry carrier was prepared by accurately weighing 40 parts of Cymel 659 styrene melamine resin, 25 parts of PM, 34.5 parts of BCS, and 0.5 parts of BL-B508W defoamer into a reactor and dispersing them evenly using a high-speed disperser to obtain 278 kg of wax slurry carrier. Then, 122 kg of wet suspended micronized wax (actual dry wax powder about 80 kg) was slowly added to the above wax slurry carrier and dispersed evenly at high speed to obtain 400 kg of suspended wax slurry with a wax powder content of about 20%.

[0072] Preparation and application of S5 coating: First, prepare a clear varnish coating by mixing 39 parts of the main resin BL-R312W, 9 parts of the curing agent Cymel 659, 2.8 parts of the neutralizing agent DMEA, 3.8 parts of the solvent BCS, 20 parts of the film-forming aid PM, 0.3 parts of the defoamer BL-B508W, and 0.4 parts of the wetting and leveling agent BL-G500W evenly to obtain a clear varnish coating for later use; under the stirring state of a high-speed disperser, add 4 parts of the suspended wax paste described in S5 to 96 parts of the clear varnish coating, and disperse evenly to obtain a special clear varnish coating containing suspended wax.

[0073] S6 coating was heat-stored to verify its suspension effect. 60g of the special coating obtained from S5 was sealed in a transparent plastic bottle and then placed in a 55℃ oven for heat storage for 7 days to observe the state of the wax powder in the coating. Example 2

[0074] The S1 low-density polymer phase was melt-modified to obtain affinity-modified micronized wax. In the melt spray granulation system, 425 kg of oxidized polyethylene wax, carnauba wax, and beeswax in a mass ratio of 5:3:2 are first heated and melted in a melting tank at 125°C with a stirring speed of 8 m / s. While maintaining a constant stirring speed, 25 kg of affinity agent methyl 4-methoxycinnamate is slowly added. After stirring for 30 minutes to ensure complete dissolution and dispersion of methyl 4-methoxycinnamate in the mixed low-density wax melt, 50 kg of D50=1.82 μm polytetrafluoroethylene micropowder wax is slowly added. After continuous stirring for 60 minutes, a uniformly dispersed suspended high-temperature melt is obtained. This suspended high-temperature melt is then transported by a material transfer pump to the nozzle of a 3 mm diameter spray granulation tower for spraying, resulting in affinity-modified wax microspheres with a diameter of 1.2 mm. These microspheres are then pulverized using air jet milling to achieve a D10=2.9 μm diameter. The affinity-modified micronized wax with D50=4.5μm and D90=6.5μm, the addition of affinity agent can significantly improve the compatibility and dispersion uniformity of polytetrafluoroethylene micronized wax in low-density wax melt, and ensure the uniform blending of low-density wax and polytetrafluoroethylene wax in the pulverized affinity-modified micronized wax particles.

[0075] Modification of the high-density inorganic phase S2 yields modified inorganic functional materials. S21 Grafting Modification: Specifically, 60 kg of alumina and 40 kg of titanium dioxide nanomaterials were added to 400 kg of an acid solution containing 20 kg of potassium permanganate. The acid solution consisted of 230 kg of a 70% p-toluenesulfonic acid aqueous solution and 170 kg of a 40% sulfuric acid aqueous solution. The mixture was dispersed at a shear rate of 2.5 m / s to ensure uniform formation of hydroxyl and / or carboxyl functional groups on the surface of the inorganic nanomaterials. After reflux at 90°C for 1 hour, surface-grafted alumina / titanium oxide was obtained. The reaction system was then separated into solid and liquid phases using a centrifuge to obtain acid-containing grafted alumina / titanium oxide. Alumina / titanium oxide; then a water washing process is performed: 100KG of the above-mentioned grafted modified alumina / titanium oxide is washed with 200KG of sodium hydroxide aqueous solution with pH=10, 150KG of sodium bicarbonate aqueous solution with pH=8 and 300KG of deionized water with pH=6.8 respectively, and the deionized water washing is performed 3 times to obtain a wet material of surface grafted modified alumina / titanium oxide with pH close to 7. Then it is transferred to a high-temperature furnace for a high-temperature drying process, where the heating temperature is 95℃ and the heating time is up to 3h, to obtain alumina / titanium oxide powder with -OH and -COOH on the surface with a water content of 1.7%; S22 Coupling Agent Bonding: In the coupling agent modification process, the alumina / titanium dioxide powder obtained in S21 is quickly transferred to a drum granulator with a stirring speed of 25 rpm. 10 kg of an affinity-modified silane coupling agent ethanol solution at 65°C and a volume concentration of 14% is sprayed onto the surface of 100 kg of continuously stirred alumina / titanium dioxide powder at a spray flow rate of 1.05 L / min. The affinity modification ratio of the silane coupling agent is vinyltrimethoxysilane A-171:methacryloyloxypropyltrimethoxysilane A-174 = 3:1. After spraying, stirring continues. The silanol groups from the hydrolysis of A-171 and A-174 form strong covalent bonds with the alumina / titanium dioxide interface. Chemical bonding improves the compatibility of alumina / titanium dioxide with organic polymers, ensuring that alumina / titanium dioxide powder can be readily blended with polymers such as low-density wax micropowder to obtain silane coupling agent-modified alumina / titanium dioxide. This modified alumina / titanium dioxide is then transferred to a 70°C oven for secondary high-temperature drying for 3.5 hours. This high-temperature treatment not only reduces the moisture content of the alumina / titanium dioxide but also promotes the full chemical bonding of A-171 and A-174 with the alumina / titanium dioxide. The modified alumina / titanium dioxide is then pulverized in an air jet mill to obtain silane coupling agent-modified nano-inorganic functional material alumina / titanium dioxide micropowder with D10=1.25μm, D50=4.33μm, and D90=6.24μm.

[0076] Preparation of S3 density-controlled suspendable micro powder wax: The low-density affinity-modified micro powder wax obtained from S1 and the high-density coupling agent-modified alumina / titanium oxide micro powder obtained from S2 were added to a V-type mixer at a mass ratio of 95:5 for blending modification to obtain suspendable micro powder wax. The mixing motor speed was 40 rpm and the mixing time was 30 min.

[0077] S4 Suspended Micropowder Wax Solvation: To solvate the suspended micropowder wax, first mix 10 parts of ethylene glycol butyl ether (BCS), 15 parts of propylene glycol methyl ether (PM), 40 parts of dipropylene glycol butyl ether (DPNB), 7 parts of ethanol (EtOH), and 35 parts of dipropylene glycol methyl ether (DPM) in a reactor to obtain 60 kg of a mixed solvent with a specific polarity. Then, slowly add 40 kg of the suspended micropowder wax obtained in S3 into the above reactor for solvation treatment. Specifically, the suspendable micronized wax powder is first uniformly dispersed in a mixed solvent under a relatively high stirring speed of 2.3 m / s. Then, the reaction system is heated to 75°C, the stirring speed is reduced to 0.5 m / s, and the temperature is maintained for 45 min to obtain the solvated suspendable micronized wax powder. The increase in temperature during this process is beneficial to improving the bonding strength between the silanol groups on the silane coupling agent and the alumina / titanium oxide. The decrease in stirring speed can promote the effective adsorption of the lipophilic groups modified by the coupling agent and the low-density wax on the surface of the affinity-modified micronized wax powder, so that the suspendable micronized wax powder forms a relatively stable whole at the microscopic level. Then, the solid-liquid mixture is separated by centrifugation to obtain a well-solventized, overall stable, wet, multiphase synergistic density-controlled suspendable micronized wax powder.

[0078] Preparation of S5 Suspended Wax Slurry: First, the solid content of the wet suspended wax obtained from S4 was weighed and calculated to be 65.33%. Second, the wax slurry carrier was prepared by accurately weighing 40 parts of Cymel 659 phenyl melamine resin, 25 parts of PM, 34.5 parts of BCS, and 0.5 parts of BL-B508W defoamer into a reactor and dispersing them evenly using a high-speed disperser to obtain 278KG of wax slurry carrier. Then, 122kg of wet suspended micronized wax (actual dry wax powder about 80KG) was slowly added to the above wax slurry carrier and dispersed evenly at high speed to obtain 400KG of suspended wax slurry with a wax powder content of about 20%.

[0079] Preparation and Application of Special Coatings S6: Preparation of Coatings Containing Suspended Micronized Wax. First, a clear varnish coating is prepared by mixing 39 parts of the main resin BL-R312W, 9 parts of curing agent Cymel 659, 2.8 parts of neutralizing agent DMEA, 3.8 parts of solvent BCS, 20 parts of film-forming aid PM, 0.3 parts of defoamer BL-B508W, and 0.4 parts of wetting and leveling agent BL-G500W until homogeneous. Then, under stirring conditions in a high-speed disperser, 4 parts of the wax slurry described in S5 are added to 96 parts of the clear varnish coating and dispersed until homogeneous to obtain a clear varnish coating containing suspended wax.

[0080] S7 coating heat storage was used to verify the suspension effect. 60g of the varnish coating containing suspended wax obtained from S6 was sealed in a transparent plastic bottle and then placed in a 55℃ oven for heat storage for 7 days to observe the state of the wax powder in the coating.

[0081] S8 Oscillation Redispersibility Verification: The special coating obtained in S7 was subjected to a slight shaking force using an oscillator at 100 rpm for 15 seconds to verify whether the suspendable micro powder wax could be redispersed in the coating. Combination Figure 1-7 The results of comparing the special coatings described in Examples 1-2 and Comparative Examples 1-4 after 7 days of heat storage at 55°C are shown in Table 1.

[0082] Table 1. The thermal storage suspension effects of Examples 1-2 and Comparative Examples 1-4 are shown in the table above. plan Main differences in formulation and process State after 7 days of heat storage at 55℃ Can it disperse again after the oscillation? Example 1 The coupling agent is: A-171 Suspended, with small clumps yes Comparative Example 1 Compared to Example 1, no affinity agent was added in step 1. All rise / Comparative Example 2 Compared to Example 1, step 2 does not involve oxidative acid treatment of the inorganic material. All rise / Comparative Example 3 Compared with Example 1, A171 is not added in step 2. Stratification, floating and settling coexist. / Comparative Example 4 Compared to Example 1, the solvation process in step 4 is omitted. All rise / Example 2 The coupling agent is: A-171:A-174 = 3:1 Suspended, with relatively large clumps yes 1. By comparing the results of Example 1 and Comparative Example 1, it can be seen that the addition of the affinity agent in the preparation process of S1 low-density affinity-modified micronized wax in Example 1 plays an important role in the suspension effect of wax powder in the coating. The addition of the affinity agent methyl 4-methoxycinnamate can improve the compatibility of low-density waxes such as oxidized polyethylene wax, carnauba wax and beeswax with polytetrafluoroethylene micronized wax. In contrast, no affinity agent was added in Comparative Example 1, and the heat storage effect was that all of them floated. This shows that the improvement of compatibility is crucial to the suspension state of wax powder after heat storage in the coating system.

[0083] 2. By comparing the results of Example 1 and Comparative Example 2, we found that in the process of modifying the nano-inorganic material with the S2 coupling agent in Example 1, it is also necessary to perform oxidative acid treatment on the inorganic material. This treatment process can introduce polar groups such as hydroxyl and carboxyl groups on the surface of the inorganic material, which is conducive to the formation of covalent bonds between the coupling agent and the inorganic nanomaterial interface and improves the compatibility between the inorganic material and the polymer wax material. In contrast, in Comparative Example 2, the oxidative acid treatment process was not performed, and the heat storage effect was that all floated. This indicates that the introduction of hydroxyl and carboxyl groups on the surface of the inorganic material plays a positive role in the heat storage and suspension effect of the final suspendable micro powder wax in the coating system.

[0084] 3. By comparing the results of Example 1 and Comparative Example 3, the addition of silane coupling agent is beneficial to the modification of inorganic nano-functional materials and improves the compatibility between inorganic materials and polymer wax materials in the modified micro-powder wax. In contrast, no silane coupling agent was added in Comparative Example 3, and the heat storage effect was characterized by stratification, with some wax floating and some wax settling, and a clear wax-free layer in the middle. This indicates that the addition of silane coupling agent has a positive effect on the heat storage and suspension effect of the final suspendable micro-powder wax in the coating system.

[0085] 4. By comparing the results of Example 1 and Comparative Example 4, the increase in temperature during the solvation process is beneficial to improving the bonding strength between the silanol groups of the silane coupling agent and the inorganic nano-functional materials. At the same time, it promotes the effective adsorption of the lipophilic groups modified by the coupling agent and the low-density wax on the surface of the affinity-modified micro-powder wax, so that the suspended micro-powder wax forms a relatively stable whole at the microscopic level. In contrast, Comparative Example 4 omitted the solvation process, and the thermal storage effect was that all of them floated. This shows that the solvation process plays an indispensable role in the thermal storage and suspension stability of the inorganic nano-material modified micro-powder wax in the coating system.

[0086] 5. By comparing the results of Example 1 and Example 2, it is not difficult to find that the use of an appropriate silane coupling agent in the process of modifying nano-inorganic materials with S2 coupling agent in Example 2 is also crucial. In Example 2, which uses a complex coupling agent, the suspension effect of the suspended micro-powder wax after heat storage in the coating system is better, and the agglomerates are larger than those in Example 1. This indicates that the type of silane coupling agent and the selection of the ratio of different types of coupling agents have a certain influence on the agglomerate morphology of the inorganic modified micro-powder wax after heat storage in the coating system. It is necessary to adapt to different systems according to the actual situation to fit the coating application of different systems.

[0087] 6. In Examples 1 and 2, the wax powder can be uniformly suspended after thermal storage and can be easily redispersed after slight shaking. This indicates that the modified multiphase synergistic density-controlled self-suspended micro powder wax can solve the problem of uneven distribution of wax powder in the coating when the material roller picks it up during the process of loading the machine, which leads to poor paint film surface.

[0088] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A self-suspended micronized wax based on multiphase synergistic density regulation and its application in coating systems, characterized in that, It includes: S1 Low-density polymer phase fusion modification: Polytetrafluoroethylene micro powder is uniformly dispersed in low-density wax melt through a special affinity agent. The suspended melt is sprayed out by spray granulation to obtain affinity-modified wax microbeads. Then, the affinity-modified wax microbeads are micronized into various types of wax powder through a pulverization process to achieve modification and obtain affinity-modified micronized wax powder. Modification of S2 high-density inorganic phase: Coupling agents are bonded to grafted nano-inorganic materials to form modified inorganic functional materials, which are used to improve the compatibility between inorganic phase and polymer phase. Preparation of S3 density-controlled suspendable micro powder wax: Low-density affinity-modified micro powder wax and high-density modified inorganic functional materials are blended and modified to obtain suspendable micro powder wax. S4 Suspended Micropowder Wax Solvation: The suspended micropowder wax is placed in a solvent system of specific polarity to complete the solvation pretreatment of the suspended micropowder wax; S5 wax paste preparation: The solubilized suspendable micro powder wax is dispersed into the wax paste base to obtain suspendable micro powder wax paste; S6 Special Coating Preparation: Disperse an appropriate amount of suspendable micro powder wax slurry into the coating system to obtain a special coating that can achieve the suspension effect of micro powder wax; S7 Wax Powder Suspension Effect Verification: The special coating was placed in an oven for heat storage to accelerate the simulation of the stability of wax powder in the paint tank and confirm the suspension effect of the micro powder wax. S8 Oscillation Redispersibility Verification: A slight shaking force is applied to the special coating after heat storage using an oscillator to verify whether the suspendable micro powder wax can be redispersed in the coating. The modified functional materials in S2 include: S21 grafting modification: surface hydroxyl or carboxyl grafting modification of nano-inorganic materials; S22 Coupling Agent Modification: Silane coupling agent is covalently bonded to the hydroxyl or carboxyl groups on the surface of the nano-inorganic functional material in S21 at 35-80℃ for 30 min-3 h to obtain coupling agent modified inorganic functional material. In S3, the preparation of suspendable micronized wax includes: blending modification of affinity-modified micronized wax and modified inorganic functional materials, with a ratio of (92-99.5):(0.5-8); In S4, the solvation of the suspendable micro powder wax includes: slowly adding the suspendable micro powder wax to a mixed solvent of ethylene glycol butyl ether (BCS), propylene glycol methyl ether (PM), dipropylene glycol butyl ether (DPNB), ethanol (EtOH), and dipropylene glycol methyl ether (DPM), heating under stirring at a temperature of 20-90℃ for 30 min-8 h.

2. The self-suspended micro powder wax based on multiphase synergistic density regulation according to claim 1 and its application in coating systems, characterized in that: The multi-type wax powders mentioned in S1 include polytetrafluoroethylene micro powder and low-density wax. The low-density wax includes one or more combinations of polyethylene, oxidized polyethylene, polypropylene, oxidized polypropylene, Fischer-Tropsch wax, carnauba wax, candelilla wax, rice bran wax, beeswax, sunflower wax, sugarcane wax, etc. The ratio of low-density wax powder: affinity agent: polytetrafluoroethylene micro powder is (40-90):(5-10):(5-35). The affinity agent includes one or more combinations of high carbon alcohols and wax esters such as methyl 4-methoxycinnamate, 4-methoxycinnamic acid, methyl p-hydroxycinnamate, and 12-hydroxy fatty acid esters.

3. The self-suspended micro powder wax based on multiphase synergistic density regulation according to claim 1 and its application in coating systems, characterized in that: In the S1 spray granulation process, the heating temperature of the melting tank is 100-260℃. After the low-density wax and affinity agent are completely melted, polytetrafluoroethylene (PTFE) micropowder is added, and stirring is continued for 5 min to 4.5 h until the PTFE micropowder is fully dispersed in the low-density wax melt with the help of the affinity agent. The nozzle diameter of the spray is 1.5-7.5 mm, the cooling temperature of the spray tower is -30~15℃, and the diameter of the obtained affinity-modified wax microspheres is 0.6-6 mm. The pulverization process is an airflow pulverization process, and after pulverization, affinity-modified micropowder wax with D50=1-5 μm is obtained.

4. The self-suspended micro powder wax based on multiphase synergistic density regulation according to claim 1 and its application in coating systems, characterized in that: The high-density nano-inorganic material in S21 is subjected to oxidation treatment and water washing treatment, wherein the mass ratio of nano-inorganic material: strong oxidant: acid solution is 10:(1.5-5):(10-50), the D50 of the nano-inorganic material is 4-8μm, and the water washing adopts a gradient water washing method with decreasing alkalinity.

5. The self-suspended micro powder wax based on multiphase synergistic density regulation according to claim 1 and its application in coating systems, characterized in that: In S22, the silane coupling agent is sprayed onto the high-density nano-inorganic functional material grafted and modified in S21 by spraying, followed by granulation, drying, and pulverization to obtain a micronized modified inorganic functional material. The mass ratio of the grafted and modified nano-inorganic functional material to the solid silane coupling agent is (97-99.5):(0.5-3). The D50 of the modified functional material obtained after pulverization is 1-5 μm.

6. The self-suspended micro powder wax based on multiphase synergistic density regulation according to claim 1 and its application in coating systems, characterized in that: The mass ratio of the mixed solvent of ethylene glycol butyl ether (BCS), propylene glycol methyl ether (PM), dipropylene glycol butyl ether (DPNB), ethanol (EtOH), and dipropylene glycol methyl ether (DPM) in S4 is BCS:PM:DPNB:EtOH:DPM = (5-15):(5-25):(25-40):(5-10):(5-50), and the mass ratio of the mixed solvent to the suspendable micronized wax is (55-85):(15-45).

7. The self-suspended micro powder wax based on multiphase synergistic density regulation according to claim 1 and its application in coating systems, characterized in that: In S5, the pre-solventized micronized wax is prepared into a mixed system, which includes resin, additives and solvent, wherein the ratio of the mixed system to the suspendable wax powder is (60-90):(10-40).

8. The self-suspended micro powder wax based on multiphase synergistic density regulation according to claim 1 and its application in coating systems, characterized in that: In S6, the suspendable wax paste is dispersed in the coating system, which includes the main resin, curing agent, additives and thinner, etc., wherein the ratio of the coating system to the suspendable wax paste is (90-97.5):(2.5-10).

9. The self-suspended micro powder wax based on multiphase synergistic density regulation according to claim 1 and its application in coating systems, characterized in that: In S7, the suspended wax special coating is placed in an oven for heat storage to accelerate the stabilization of the wax powder in the paint tank. The oven temperature is 25-70℃, and the heat storage time is 1-90 days, preferably 35-60℃ for 7-30 days.

10. The self-suspended micro powder wax based on multiphase synergistic density regulation according to claim 1 and its application in coating systems, characterized in that: In S8, the special coating that can be suspended after heat storage is placed on a vibrator for a vibration experiment to verify whether the suspended micro powder wax can be redispersed. The vibration parameters of the vibrator are 10-200 rpm and 5-300 s, preferably 80-150 rpm and 10-60 s.

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