Environment-friendly fluorine-free super-hydrophobic coating material and preparation method thereof

Abstract

The application discloses an environment-friendly fluorine-free super-hydrophobic coating material and a preparation method thereof, and belongs to the technical field of super-hydrophobic coating materials. The preparation method comprises the following steps: mixing hyperbranched polyurethane, ethyl acetate and propylene glycol methyl ether acetate for 10-20 min, then adding polydimethylsiloxane and octadecyl isocyanate to carry out mixing reaction for 60-80 min, then adding multistage microspheres to carry out ultrasonic treatment for 15-30 min, and then adding Isopar G, isophorone diisocyanate, silane coupling agent KH-560, dibutyl tin dilaurate and triethylenediamine to carry out stirring and dispersion for 30-50 min, so as to obtain the environment-friendly fluorine-free super-hydrophobic coating material. The environment-friendly fluorine-free super-hydrophobic coating material prepared by the application has good super-hydrophobicity, self-repairing function and wear resistance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of super-hydrophobic coating materials, in particular to an environmentally friendly fluorine-free super-hydrophobic coating material and a preparation method thereof. BACKGROUND

[0002] In the field of material protection, super-hydrophobic coatings have become a key protection scheme in high-end fields such as aerospace, deep-sea equipment and energy facilities due to their unique self-cleaning, anti-icing, corrosion and rust prevention and other core characteristics. Such coatings can achieve a super-hydrophobic state with a liquid contact angle of > 150° by constructing a special surface structure, which can effectively resist liquid erosion, reduce surface contamination and significantly prolong the service life of equipment. However, the current mainstream super-hydrophobic coating technology still faces three major industry bottlenecks that need to be broken through in practical applications, which seriously restricts its large-scale promotion.

[0003] The core of super-hydrophobic performance relies on the synergistic effect of micro-nano rough structure and low surface energy material, but mechanical wear can easily damage this precise structure, leading to irreversible decay of hydrophobicity. Traditional self-healing coatings mostly use a single repair mechanism (such as hydrogen bond recombination, dynamic coordination bond reconstruction, etc.), which can only deal with molecular-level micro-damage and completely fails in the face of deep scratches or large-area wear, greatly shortening the actual service period of the coating. To improve wear resistance, existing solutions often introduce rigid reinforcing phases such as SiO2 and TiO2, but there are serious interface compatibility problems between these inorganic microparticles and the organic polymer matrix, which can easily form stress concentration points under cyclic stress, leading to microsphere detachment or coating cracking.

[0004] CN 103409028A prepared a photocatalytic self-healing super-hydrophobic coating and a preparation method thereof, which used hydrophobically modified nanoparticles, photocatalytic nanoparticles and low surface energy materials containing active groups to prepare a coating. The super-hydrophobic coating obtained after drying the coating can realize self-repair of the surface structure under UV irradiation after wear. However, due to the uncontrollability of UV irradiation crosslinking, self-repair may only be one-time, and the durability of the super-hydrophobic coating is still difficult to solve.

[0005] Therefore, it is an important problem to be solved in the field to provide a fluorine-free super-hydrophobic coating material with good self-repairing performance. SUMMARY

[0006] To solve the problems in the prior art, the present application provides an environmentally friendly fluorine-free super-hydrophobic coating material and a preparation method thereof. Specifically, the technical solution of the present application includes the following contents:

[0007] A preparation method of an environmentally friendly fluorine-free super-hydrophobic coating material, the preparation method comprising the following steps:

[0008] The hyperbranched polyurethane, ethyl acetate and propylene glycol methyl ether acetate are mixed for 10-20 min, then polydimethylsiloxane and octadecyl isocyanate are added and mixed for 60-80 min, then the multi-stage microspheres are ultrasonically treated for 15-30 min, then Isopar G, isophorone diisocyanate, silane coupling agent KH-560, dibutyl tin dilaurate and triethylenediamine are added and stirred and dispersed for 30-50 min to obtain the environmentally friendly fluorine-free super-hydrophobic coating material.

[0009] Further, the preparation method of the hyperbranched polyurethane comprises the following steps:

[0010] 3,4-dihydroxybenzoic acid and allyl boronic pinacol ester are mixed and reacted to obtain a first intermediate;

[0011] The first intermediate, hydroxyethyl methacrylate, EDC and DMAP are mixed and reacted to obtain a second intermediate;

[0012] The second intermediate, β-mercaptoethanol and 2,2-dimethoxy-phenyl acetophenone are mixed and treated by irradiation with a 395 nm LED light source to obtain a modified borate ester;

[0013] Trimethylolpropane, dimethylolpropionic acid and isophorone diisocyanate are mixed for 30-50 min, then dibutyl tin diacetate is added and mixed and reacted to obtain a first intermediate system;

[0014] The first intermediate system and the modified borate ester are mixed and reacted to obtain a second intermediate system;

[0015] The second intermediate system and hydroxyl-terminated polydimethylsiloxane are mixed and reacted for 3-5 h, then triethylamine is added and mixed and reacted for 30-60 min, and then deionized water is added and mixed and reacted for 40-60 min to obtain the hyperbranched polyurethane.

[0016] Further, the weight ratio of the 3,4-dihydroxybenzoic acid and the allyl boronic pinacol ester is 4.1-4.5:5.7-6.1.

[0017] Further, the reaction conditions of the mixing and reaction of the 3,4-dihydroxybenzoic acid and the allyl boronic pinacol ester include a reaction temperature of 60-70℃ and a reaction time of 4-6 h.

[0018] Further, the weight ratio of the first intermediate, hydroxyethyl methacrylate, EDC and DMAP is 7-9:5-7:8-10:4-6.

[0019] Further, the reaction conditions of the mixing and reaction of the first intermediate, hydroxyethyl methacrylate, EDC and DMAP include a reaction temperature of 23-25℃ and a reaction time of 24-48 h.

[0020] Further, the weight ratio of the second intermediate, beta-mercaptoethanol and 2,2-dimethoxy-phenylacetophenone is 5-7:2.5-3.5:0.05-0.1.

[0021] Further, the conditions of the 395nm LED light source treatment include a treatment power of 50-80mW / cm 2 and a treatment time of 30-50min.

[0022] Further, the weight ratio of the trimethylolpropane, dimethylolpropanoic acid, isophorone diisocyanate, dibutyl tin diacetate, modified borate, hydroxyl-terminated polydimethylsiloxane, triethylamine and deionized water is 5.5-7.5:3-5:20-25:0.015-0.03:6-8:6.5-8.5:2-4:140-160.

[0023] Further, the conditions of the trimethylolpropane and isophorone diisocyanate mixed reaction include a reaction temperature of 60-70℃ and a reaction time of 3-5h.

[0024] Further, the conditions of the first intermediate and modified borate mixed reaction include a reaction temperature of 50-60℃ and a reaction time of 2-4h.

[0025] Further, the preparation method of the multi-stage microspheres includes the following steps:

[0026] After mixing and stirring the diatomite and 10wt% hydrochloric acid solution, the activated diatomite is obtained by high-temperature calcination;

[0027] The mixed solution is obtained by mixing zinc nitrate dihydrate and triethylamine;

[0028] The growth solution is obtained by mixing hexamethylenetetramine and zinc nitrate hexahydrate;

[0029] The diatomite intermediate is obtained by dispersing the activated diatomite in the mixed solution and soaking for 5-15min;

[0030] The zinc oxide diatomite composite is obtained by mixing and reacting the diatomite intermediate and the growth solution;

[0031] The zinc sulfide diatomite composite is obtained by mixing and reacting the zinc oxide diatomite composite and sodium sulfide;

[0032] The multi-stage microspheres are obtained by mixing and reacting the zinc sulfide diatomite composite and n-octadecyl phosphate.

[0033] Further, the conditions of the diatomite and 10wt% hydrochloric acid solution stirring reaction include a reaction temperature of 70-80℃ and a reaction time of 2-4h.

[0034] Further, the high-temperature calcination condition includes a calcination temperature of 800-850℃ and a calcination time of 2-3h.

[0035] Further, the weight ratio of the activated diatomite, zinc nitrate dihydrate, triethylamine, hexamethylenetetramine and zinc nitrate hexahydrate is 50:1.8-2.2:1.2-1.4:1.4-1.6:2.9-3.3.

[0036] Further, the mixing reaction condition of the diatomite intermediate and the growth solution includes incubation treatment at 90-100℃ for 3h, and then cooling to 25℃ for 10-12h.

[0037] Further, the weight ratio of the zinc oxide diatomite compound and sodium sulfide is 1.8-2.2:5.9-6.3.

[0038] Further, the mixing reaction condition of the zinc oxide diatomite compound and sodium sulfide includes a reaction temperature of 75-85℃ and a reaction time of 2-3h.

[0039] Further, the weight ratio of the zinc sulfide diatomite compound and n-octadecyl phosphate is 50:0.25-0.45.

[0040] Further, the mixing reaction condition of the zinc sulfide diatomite compound and n-octadecyl phosphate includes ultrasonic treatment at a power of 400W for 60min, and then heat treatment at 100-120℃ for 30-60min.

[0041] Further, the weight ratio of the hyperbranched polyurethane, ethyl acetate, propylene glycol methyl ether acetate, dimethicone, octadecyl isocyanate, multi-stage microspheres, Isopar G, isophorone diisocyanate, silane coupling agent KH-560, dibutyltin dilaurate and triethylenediamine is 65-75:20-30:14-16:2-4:0.7-0.9:4-6:9-11:2.6-3.0:0.6-0.8:0.03-0.05:0.07-0.09.

[0042] Compared with the prior art, the present application has the following beneficial effects:

[0043] (1) In the present application, the activated diatomite is obtained by acid treatment and high-temperature calcination treatment of diatomite, the activated diatomite is sequentially soaked in a mixed solution and a growth solution and subjected to a hydrothermal reaction to load columnar zinc oxide on the surface of the activated diatomite to obtain a zinc oxide diatomite composite, after treatment with sodium sulfide, the zinc oxide is converted into zinc sulfide to obtain a zinc sulfide diatomite composite, the phosphoric acid group of n-octadecyl phosphate is combined with the zinc ion on the surface of the zinc sulfide diatomite composite by coordination to obtain a multi-level microsphere; a first intermediate is obtained by borate ester exchange reaction of 3,4-dihydroxybenzoic acid and allyl borate pinacol ester, the first intermediate and hydroxyethyl methacrylate are subjected to esterification reaction to obtain a second intermediate, the second intermediate and beta-mercaptoethanol are subjected to thiol-olefin click reaction to obtain a modified borate ester; trimethylolpropane and isophorone diisocyanate are reacted to obtain a first intermediate system, the hydroxyl group of the modified borate ester is reacted with the isocyanate group of the first intermediate system to obtain a second intermediate system, and the hydroxyl-terminated polydimethylsiloxane is reacted with the residual isocyanate group in the second intermediate system to obtain a hyperbranched polyurethane.

[0044] (2) The environmentally friendly fluorine-free superhydrophobic coating material prepared in the present application has good superhydrophobic performance, which is due to the synergistic effect of the multi-level microspheres and the hyperbranched polyurethane: the dandelion-shaped multi-level microspheres are composed of zinc sulfide diatomite composite and n-octadecyl phosphate, and the unique layered rough structure on the surface provides a physical basis for the superhydrophobic performance, the stable skeleton of the zinc sulfide diatomite composite ensures the persistence of the rough structure, and the n-octadecyl phosphate endows the material with low surface energy characteristics; the high-elasticity and flexible network structure formed by the hyperbranched polyurethane further enhances the mechanical stability of the coating as a whole, so that the coating can still maintain stable superhydrophobic state after long-term use, effectively resisting the damage of the external environment to the hydrophobic performance.

[0045] (3) The environmentally friendly fluorine-free superhydrophobic coating material prepared in the present application has good self-repairing function, prolonging the service life, the modified borate ester introduced in the hyperbranched polyurethane contains a dynamic borate ester bond, which can undergo exchange reaction under external stimulus: heat treatment can cause the reversible dissociation of the borate ester bond, and the dissociated o-diphenol structure can automatically oxidize and polymerize at the wear interface to form a repair layer, this mechanism enables the coating to restore its original superhydrophobic performance and complete structure after multiple damages, greatly reducing the performance failure problem caused by damage, and significantly prolonging the service life of the coating.

[0046] (4) The environmentally friendly fluorine-free superhydrophobic coating material prepared in the present application has good wear resistance, the high elasticity and flexibility of the hyperbranched polyurethane network, combined with the skeleton supporting effect of the dandelion-shaped multi-level microspheres, effectively improve the anti-wear ability of the coating, ensure that it is not easy to fail due to mechanical action in actual use, and further ensure the long-term performance. DETAILED DESCRIPTION

[0047] The technical solution of the present invention will be clearly and completely described below through embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] Unless otherwise stated, all raw materials and reagents used in this invention are commercially available or can be prepared by known methods.

[0049] Preparation Example 1:

[0050] The preparation method of hyperbranched polyurethane includes the following steps:

[0051] 4.1 parts by weight of 3,4-dihydroxybenzoic acid and 5.7 parts by weight of allyl borate pinacol ester were dispersed in 50 parts by weight of THF. The mixture was stirred and reacted at 60°C for 4 hours under argon protection. After the reaction was completed, THF was removed by rotary evaporation and the mixture was dried under vacuum at 50°C for 8 hours to obtain the first intermediate.

[0052] 7 parts by weight of the first intermediate, 5 parts by weight of hydroxyethyl methacrylate, 8 parts by weight of EDC and 4 parts by weight of DMAP were dispersed in 100 parts by weight of DMSO and stirred at 23°C for 24 hours. After the reaction was completed, the DMSO was removed by rotary evaporation, and the second intermediate was obtained by lyophilization after dialysis with deionized water for 2 days.

[0053] 5 parts by weight of the second intermediate, 2.5 parts by weight of β-mercaptoethanol, and 0.05 parts by weight of 2,2-dimethoxy-phenylacetophenone were dispersed in 20 parts by weight of anhydrous ethanol, and the mixture was subjected to nitrogen protection at 50 mW / cm⁻¹. 2 The mixture was irradiated with a 395nm LED light source for 30 min. After the reaction was completed, the ethanol was removed by rotary evaporation. The mixture was washed with deionized water until neutral and then distilled under reduced pressure to obtain the modified borate ester.

[0054] 5.5 parts by weight of trimethylolpropane, 3 parts by weight of dimethylolpropionic acid and 20 parts by weight of isophorone diisocyanate were dispersed in 100 parts by weight of acetone and stirred at 300 r / min at 60 °C for 30 min under nitrogen protection. Then 0.015 parts by weight of dibutyltin diacetate were added and the reaction was continued for 3 h to obtain the first intermediate system.

[0055] The first intermediate system was cooled to 50°C, and 6 parts by weight of modified borate ester were added and stirred for 2 hours to obtain the second intermediate system.

[0056] 6.5 parts by weight of hydroxyl-terminated polydimethylsiloxane is added into the above-mentioned second intermediate system, and after stirring and reacting for 3 h, the temperature is lowered to 40 °C, 2 parts by weight of triethylamine is added, and after stirring and reacting for 30 min, 140 parts by weight of deionized water is added, and emulsification treatment is carried out at a rotation speed of 12000 r / min for 40 min. After the reaction is completed, acetone is removed by rotary evaporation to obtain the hyperbranched polyurethane.

[0057] Preparation Example 2:

[0058] The method for preparing the hyperbranched polyurethane comprises the following steps:

[0059] 4.2 parts by weight of 3,4-dihydroxybenzoic acid and 5.8 parts by weight of allylboronic pinacol ester are dispersed in 50 parts by weight of THF, and stirring and reaction are carried out at 62 °C for 4.5 h in an argon protection environment. After the reaction is completed, THF is removed by rotary evaporation, and vacuum drying is carried out at 50 °C for 8 h to obtain the first intermediate;

[0060] 7.5 parts by weight of the first intermediate, 5.5 parts by weight of hydroxyethyl methacrylate, 8.5 parts by weight of EDC and 4.5 parts by weight of DMAP are dispersed in 100 parts by weight of DMSO, and stirring and reaction are carried out at 23.5 °C for 30 h. After the reaction is completed, DMSO is removed by rotary evaporation, and dialysis is carried out with deionized water for 2 days, and then freeze-drying is carried out to obtain the second intermediate;

[0061] 5.5 parts by weight of the second intermediate, 2.7 parts by weight of β-mercaptoethanol and 0.06 parts by weight of 2,2-dimethoxy-phenylacetophenone are dispersed in 20 parts by weight of anhydrous ethanol, and irradiation treatment is carried out with a 55 mW / cm 2 of a 395 nm LED light source in a nitrogen protection environment for 35 min. After the reaction is completed, ethanol is removed by rotary evaporation, and washing is carried out with deionized water until neutral, and then vacuum distillation is carried out to obtain the modified borate ester;

[0062] 6 parts by weight of trimethylolpropane, 3.5 parts by weight of dimethylolpropionic acid and 21 parts by weight of isophorone diisocyanate are dispersed in 100 parts by weight of acetone, and stirring and mixing are carried out at 62 °C at a rotation speed of 300 r / min for 30 min in a nitrogen protection environment. Then, 0.018 parts by weight of dibutyl tin diacetate is added, and stirring and reaction are carried out for 3.5 h to obtain the first intermediate system;

[0063] The first intermediate system is lowered to 53 °C, 6.5 parts by weight of the modified borate ester is added, and stirring and reaction are carried out for 2.5 h to obtain the second intermediate system;

[0064] 7 parts by weight of hydroxyl-terminated polydimethylsiloxane were added to the above-mentioned second intermediate system, and after continuing to stir and react for 3.5 h, the temperature was lowered to 40°C, 2.5 parts by weight of triethylamine was added, and after stirring and reacting for 35 min, 145 parts by weight of deionized water was added, and emulsification treatment was carried out at a rotation speed of 12000 r / min for 45 min. After the reaction was completed, acetone was removed by rotary evaporation to obtain the hyperbranched polyurethane.

[0065] Preparation Example 3:

[0066] The preparation method of the hyperbranched polyurethane comprises the following steps:

[0067] 4. 3 parts by weight of 3,4-dihydroxybenzoic acid and 5.9 parts by weight of allyl borate pinacol ester were dispersed in 50 parts by weight of THF, and stirring and reaction were carried out at 65°C for 5 h in an argon protection environment. After the reaction was completed, THF was removed by rotary evaporation, and vacuum drying was carried out at 50°C for 8 h to obtain a first intermediate;

[0068] 8 parts by weight of the first intermediate, 6 parts by weight of hydroxyethyl methacrylate, 9 parts by weight of EDC and 5 parts by weight of DMAP were dispersed in 100 parts by weight of DMSO, and stirring and reaction were carried out at 24.5°C for 36 h. After the reaction was completed, DMSO was removed by rotary evaporation, and dialysis was carried out with deionized water for 2 days, and then freeze-drying was carried out to obtain a second intermediate;

[0069] 6 parts by weight of the second intermediate, 3 parts by weight of β-mercaptoethanol and 0.07 parts by weight of 2,2-dimethoxy-phenyl phenylacetophenone were dispersed in 20 parts by weight of anhydrous ethanol, and irradiation treatment was carried out with a 60 mW / cm 2 of a 395 nm LED light source in a nitrogen protection environment for 40 min. After the reaction was completed, ethanol was removed by rotary evaporation, and washing was carried out with deionized water until neutral, and then vacuum distillation was carried out to obtain a modified borate ester;

[0070] 6.5 parts by weight of trimethylolpropane, 4 parts by weight of dimethylolpropionic acid and 22 parts by weight of isophorone diisocyanate were dispersed in 100 parts by weight of acetone, and stirring and mixing were carried out at 65°C at a rotation speed of 300 r / min for 30 min in a nitrogen protection environment. Then, 0.02 parts by weight of dibutyl tin diacetate was added, and stirring and reaction were continued for 4 h to obtain a first intermediate system;

[0071] The first intermediate system was cooled to 55°C, 7 parts by weight of the modified borate ester was added, and stirring and reaction were carried out for 3 h to obtain a second intermediate system;

[0072] 7.5 parts by weight of hydroxyl-terminated polydimethylsiloxane was added to the above-mentioned second intermediate system, and after continuing to stir and react for 4 h, the temperature was lowered to 40°C, 3 parts by weight of triethylamine was added, and after stirring and reacting for 40 min, 150 parts by weight of deionized water was added, and emulsification treatment was carried out at a rotation speed of 12000 r / min for 50 min. After the reaction was completed, acetone was removed by rotary evaporation to obtain the hyperbranched polyurethane.

[0073] Preparation Example 4:

[0074] The preparation method of the hyperbranched polyurethane comprises the following steps:

[0075] 4.4 parts by weight of 3,4-dihydroxybenzoic acid and 6.0 parts by weight of allyl borate pinacol ester are dispersed in 50 parts by weight of THF, and stirred at 67°C for 5.5 hours in an argon protection environment. After the reaction is completed, THF is removed by rotary evaporation, and vacuum drying is performed at 50°C for 8 hours to obtain a first intermediate;

[0076] 8.5 parts by weight of the first intermediate, 6.5 parts by weight of hydroxyethyl methacrylate, 9.5 parts by weight of EDC, and 5.5 parts by weight of DMAP are dispersed in 100 parts by weight of DMSO, and stirred at 24°C for 42 hours. After the reaction is completed, DMSO is removed by rotary evaporation, dialyzed with deionized water for 2 days, and then freeze-dried to obtain a second intermediate;

[0077] 6.5 parts by weight of the second intermediate, 3.2 parts by weight of β-mercaptoethanol, and 0.08 parts by weight of 2,2-dimethoxy-phenyl phenylacetophenone are dispersed in 20 parts by weight of anhydrous ethanol, and treated with a 70 mW / cm 2 of a 395 nm LED light source for 45 minutes in a nitrogen protection environment. After the reaction is completed, ethanol is removed by rotary evaporation, washed with deionized water until neutral, and then distilled under reduced pressure to obtain a modified borate ester;

[0078] 7 parts by weight of trimethylolpropane, 4.5 parts by weight of dimethylolpropionic acid, and 24 parts by weight of isophorone diisocyanate are dispersed in 100 parts by weight of acetone, and stirred at a rotation speed of 300 r / min at 68°C for 30 minutes in a nitrogen protection environment. Then, 0.025 parts by weight of dibutyl tin diacetate is added, and the stirring reaction is continued for 4.5 hours to obtain a first intermediate system;

[0079] The first intermediate system is cooled to 58°C, 7.5 parts by weight of the modified borate ester is added, and stirred for 3.5 hours to obtain a second intermediate system;

[0080] 8 parts by weight of hydroxyl-terminated polydimethylsiloxane is added to the above-mentioned second intermediate system, and the stirring reaction is continued for 4.5 hours. Then, the temperature is lowered to 40°C, 3.5 parts by weight of triethylamine is added, and stirred for 50 minutes. Then, 155 parts by weight of deionized water is added, and emulsified at a rotation speed of 12000 r / min for 55 minutes. After the reaction is completed, acetone is removed by rotary evaporation to obtain the hyperbranched polyurethane.

[0081] Preparation Example 5:

[0082] The preparation method of the hyperbranched polyurethane comprises the following steps:

[0083] 4.5 parts by weight of 3,4-dihydroxybenzoic acid and 6.1 parts by weight of allylboronic pinacol ester are dispersed in 50 parts by weight of THF, and the reaction is stirred at 70°C for 6 hours under an argon atmosphere. After the reaction is completed, THF is removed by rotary evaporation, and vacuum drying is performed at 50°C for 8 hours to obtain a first intermediate;

[0084] 9 parts by weight of the first intermediate, 7 parts by weight of hydroxyethyl methacrylate, 10 parts by weight of EDC, and 6 parts by weight of DMAP are dispersed in 100 parts by weight of DMSO, and the reaction is stirred at 25°C for 48 hours. After the reaction is completed, DMSO is removed by rotary evaporation, and dialysis is performed using deionized water for 2 days, followed by freeze drying to obtain a second intermediate;

[0085] 7 parts by weight of the second intermediate, 3.5 parts by weight of β-mercaptoethanol, and 0.1 part by weight of 2,2-dimethoxy-phenyl phenyl ethanone are dispersed in 20 parts by weight of anhydrous ethanol, and the reaction is performed using an 80 mW / cm 2 of a 395 nm LED light source for 50 minutes under a nitrogen atmosphere. After the reaction is completed, ethanol is removed by rotary evaporation, and washing is performed using deionized water until neutralization. Then, vacuum distillation is performed to obtain a modified borate ester;

[0086] 7.5 parts by weight of trimethylolpropane, 5 parts by weight of dimethylolpropionic acid, and 25 parts by weight of isophorone diisocyanate are dispersed in 100 parts by weight of acetone, and the mixture is stirred at 70°C at a rotation speed of 300 r / min for 30 minutes under a nitrogen atmosphere. Then, 0.03 parts by weight of dibutyl tin diacetate is added, and the reaction is continued for 5 hours to obtain a first intermediate system;

[0087] The first intermediate system is cooled to 60°C, 8 parts by weight of the modified borate ester is added, and the reaction is stirred for 4 hours to obtain a second intermediate system;

[0088] 8.5 parts by weight of a hydroxyl-terminated polydimethylsiloxane is added to the above second intermediate system, and the reaction is continued to stir for 5 hours. Then, the system is cooled to 40°C, 4 parts by weight of triethylamine is added, and the reaction is stirred for 60 minutes. Then, 160 parts by weight of deionized water is added, and the emulsification is performed at a rotation speed of 12,000 r / min for 60 minutes. After the reaction is completed, acetone is removed by rotary evaporation to obtain a hyperbranched polyurethane.

[0089] Preparation Example 6:

[0090] The method for preparing the hyperbranched polyurethane includes the following steps:

[0091] The modified borate ester in Preparation Example 5 is removed, and the other operations are the same as those in Preparation Example 5.

[0092] Preparation Example 7:

[0093] The method for preparing the modified polyurethane includes the following steps:

[0094] 4.5 parts by weight of 3,4-dihydroxybenzoic acid and 6.1 parts by weight of phenylboronic acid pinacol ester are dispersed in 50 parts by weight of THF, and the reaction is stirred at 70°C for 6h under an argon atmosphere. After the reaction is completed, the THF is removed by rotary evaporation, and the first intermediate is obtained by drying under vacuum at 50°C for 8h;

[0095] 9 parts by weight of the first intermediate, 7 parts by weight of hydroxyethyl methacrylate, 10 parts by weight of EDC, and 6 parts by weight of DMAP are dispersed in 100 parts by weight of DMSO, and the reaction is stirred at 25°C for 48h. After the reaction is completed, the DMSO is removed by rotary evaporation, and the second intermediate is obtained by dialysis against deionized water for 2 days and freeze-drying;

[0096] 7 parts by weight of the second intermediate, 3.5 parts by weight of β-mercaptoethanol, and 0.1 part by weight of 2,2-dimethoxy-phenyl phenyl ethanone are dispersed in 20 parts by weight of anhydrous ethanol, and the reaction is irradiated with an 80mW / cm2 395nm LED light source for 50min under a nitrogen atmosphere. After the reaction is completed, the ethanol is removed by rotary evaporation, and the modified borate ester is obtained by washing with deionized water until neutral and distillation under reduced pressure;

[0097] 7.5 parts by weight of trimethylolpropane, 5 parts by weight of dimethylolpropionic acid, and 25 parts by weight of isophorone diisocyanate are dispersed in 100 parts by weight of acetone, and the mixture is stirred at 70°C for 30min at a rotation speed of 300r / min under a nitrogen atmosphere. Then, 0.03 parts by weight of dibutyl tin diacetate is added, and the reaction is continued for 5h to obtain the first intermediate system;

[0098] The first intermediate system is cooled to 60°C, 8 parts by weight of the modified borate ester is added, and the reaction is stirred for 4h to obtain the second intermediate system. Then, 4 parts by weight of triethylamine is added, and the reaction is stirred for 60min. After that, 160 parts by weight of deionized water is added, and the emulsification is carried out at a rotation speed of 12000r / min for 60min. After the reaction is completed, the acetone is removed by rotary evaporation to obtain the modified polyurethane.

[0099] Preparation Example 8:

[0100] The preparation method of the multi-stage microspheres comprises the following steps:

[0101] 20 parts by weight of diatomite is dispersed in 200 parts by weight of a 10wt% hydrochloric acid solution, and the reaction is stirred at 70°C for 2h. After the reaction is completed, the mixture is suction-filtered, washed with deionized water until neutral, and then calcined in a muffle furnace at a temperature increasing rate of 5°C / min to 800°C for 2h to obtain the activated diatomite;

[0102] 1.8 parts by weight of zinc nitrate dihydrate is dispersed in 100 parts by weight of isopropyl alcohol, and the mixture is stirred at 85°C for 15min. Then, 1.2 parts by weight of triethylamine is added, and the stirring is continued for 15min. After that, the mixture is cooled to 23°C and left standing for 3h to obtain the mixed solution;

[0103] 1.4 6.0 parts by weight of hexamethylenetetramine and 2.9 parts by weight of zinc nitrate hexahydrate are dispersed in 100 parts by weight of deionized water, and dispersed by stirring at 25°C for 20 min to obtain a growth solution;

[0104] 50 parts by weight of activated diatomite are dispersed in the above mixed solution, soaked for 5 min, washed with ethanol several times, dried in an oven at 120°C for 1 h, and left to stand at 25°C for 24 h to obtain a diatomite intermediate;

[0105] The diatomite intermediate and the growth solution are mixed and transferred into a high-temperature reaction kettle lined with polytetrafluoroethylene, left to stand at 25°C for 10 h after heat treatment at 90°C for 3 h, washed with deionized water and anhydrous ethanol alternately, and vacuum dried at 75°C for 8 h to obtain a zinc oxide diatomite composite;

[0106] 1.8 parts by weight of the zinc oxide diatomite composite and 5.9 parts by weight of sodium sulfide are dispersed in 50 parts by weight of deionized water, ultrasonically dispersed for 10 min, and stirred at 75°C for 2 h in a nitrogen protection environment, and the zinc sulfide diatomite composite is obtained by filtration, washing, and vacuum drying in sequence after the reaction is completed;

[0107] 50 parts by weight of the zinc sulfide diatomite composite and 0.25 parts by weight of n-octadecyl phosphate are dispersed in 500 parts by weight of ethanol, ultrasonically treated at a power of 400 W for 60 min, and the solid is collected by centrifugation, washed with ethanol several times, and heat treated at 100°C for 30 min to obtain the multi-stage microspheres.

[0108] Preparation Example 9:

[0109] The method for preparing the multi-stage microspheres comprises the following steps:

[0110] 20 parts by weight of diatomite are dispersed in 200 parts by weight of a 10 wt% hydrochloric acid solution, stirred and reacted at 72°C for 2.5 h, filtered by suction after the reaction is completed, washed with deionized water until neutral, and calcined in a muffle furnace at a temperature increasing rate of 5°C / min to 810°C for 2.2 h to obtain activated diatomite;

[0111] 1.9 parts by weight of zinc nitrate dihydrate are dispersed in 100 parts by weight of isopropyl alcohol, dispersed by stirring at 85°C for 15 min, 1.25 parts by weight of triethylamine is added, stirring is continued for 15 min, and the mixed solution is obtained by cooling to 24°C and standing for 3 h;

[0112] 1.45 parts by weight of hexamethylenetetramine and 3.0 parts by weight of zinc nitrate hexahydrate are dispersed in 100 parts by weight of deionized water, and dispersed by stirring at 25°C for 20 min to obtain a growth solution;

[0113] 50 parts by weight of the activated diatomite was dispersed in the above mixed solution, soaked for 7 min, washed with ethanol for several times, dried in an oven at 120°C for 1 h, and left at 25°C for 24 h to obtain a diatomite intermediate;

[0114] The diatomite intermediate and the growth solution were mixed and transferred into a high-temperature reaction kettle lined with polytetrafluoroethylene, and after being kept at 92°C for 3 h, cooled to 25°C and left for 10 h, washed with deionized water and anhydrous ethanol alternately, and vacuum dried at 75°C for 8 h, a zinc oxide diatomite composite was obtained;

[0115] 1.9 parts by weight of the zinc oxide diatomite composite and 6.0 parts by weight of sodium sulfide were dispersed in 50 parts by weight of deionized water, ultrasonically dispersed for 12 min, and then stirred and reacted at 77°C for 2.2 h in a nitrogen protection environment. After the reaction was completed, the zinc sulfide diatomite composite was obtained by filtration, washing, and vacuum drying in sequence;

[0116] 50 parts by weight of the zinc sulfide diatomite composite and 0.3 parts by weight of n-octadecyl phosphate were dispersed in 500 parts by weight of ethanol, and ultrasonically treated at a power of 400 W for 60 min. After centrifugal collection of the solid, the solid was washed with ethanol for several times, and then heat-treated at 105°C for 35 min to obtain the multi-stage microspheres.

[0117] Preparation Example 10:

[0118] The method for preparing the multi-stage microspheres comprises the following steps:

[0119] 20 parts by weight of diatomite was dispersed in 200 parts by weight of 10 wt% hydrochloric acid solution, and stirred and reacted at 75°C for 3 h. After the reaction was completed, the activated diatomite was obtained by filtration, washing with deionized water until neutral, and calcining in a muffle furnace at a temperature increasing rate of 5°C / min to 820°C for 2.5 h;

[0120] 2.0 parts by weight of zinc nitrate dihydrate was dispersed in 100 parts by weight of isopropyl alcohol, and stirred and dispersed at 85°C for 15 min. Then, 1.3 parts by weight of triethylamine was added, and the stirring was continued for 15 min, and then the mixture was cooled to 23°C and left for 3 h to obtain a mixed solution;

[0121] 1.5 parts by weight of hexamethylenetetramine and 3.1 parts by weight of zinc nitrate hexahydrate were dispersed in 100 parts by weight of deionized water, and stirred and dispersed at 25°C for 20 min to obtain a growth solution;

[0122] 50 parts by weight of the activated diatomite was dispersed in the above mixed solution, soaked for 7 min, washed with ethanol for several times, dried in an oven at 120°C for 1 h, and left at 25°C for 24 h to obtain a diatomite intermediate;

[0123] The diatomite intermediate and the growth solution are mixed and transferred into a high-temperature reaction kettle lined with polytetrafluoroethylene, and after heat preservation treatment at 95°C for 3h, it is cooled to 25°C and left standing for 10h. After being washed alternately with deionized water and anhydrous ethanol, vacuum drying at 75°C for 8h obtains the zinc oxide diatomite composite;

[0124] 2.0 parts by weight of zinc oxide diatomite composite and 6.1 parts by weight of sodium sulfide are dispersed in 50 parts by weight of deionized water, and after ultrasonic dispersion for 15min, stirring reaction is carried out at 80°C for 2.5h in a nitrogen protection environment. After the reaction is completed, the zinc sulfide diatomite composite is obtained by filtration, washing and vacuum drying in sequence;

[0125] 50 parts by weight of zinc sulfide diatomite composite and 0.35 parts by weight of n-octadecyl phosphate are dispersed in 500 parts by weight of ethanol, and after ultrasonic treatment at a power of 400W for 60min, the solid is collected by centrifugation, washed with ethanol several times, and heat treated at 110°C for 40min to obtain the multi-stage microspheres.

[0126] Preparation Example 11:

[0127] The preparation method of the multi-stage microspheres comprises the following steps:

[0128] 20 parts by weight of diatomite are dispersed in 200 parts by weight of 10wt% hydrochloric acid solution, and after stirring reaction at 77°C for 3.5h, the activated diatomite is obtained by filtration, washing with deionized water until neutral, and calcining in a muffle furnace at a temperature increasing rate of 5°C / min to 830°C for 2.7h;

[0129] 2.1 parts by weight of zinc nitrate dihydrate are dispersed in 100 parts by weight of isopropyl alcohol, and after stirring dispersion at 85°C for 15min, 1.35 parts by weight of triethylamine is added, and after continuing to stir for 15min, the mixture is cooled to 24°C and left standing for 3h to obtain a mixed solution;

[0130] 1.55 parts by weight of hexamethylenetetramine and 3.2 parts by weight of zinc nitrate hexahydrate are dispersed in 100 parts by weight of deionized water, and after stirring dispersion at 25°C for 20min, the growth solution is obtained;

[0131] 50 parts by weight of activated diatomite are dispersed in the above-mentioned mixed solution, and after soaking treatment for 12min, the diatomite intermediate is obtained by washing with ethanol several times, drying in an oven at 120°C for 1h, and standing at 25°C for 24h;

[0132] The diatomite intermediate and the growth solution are mixed and transferred into a high-temperature reaction kettle lined with polytetrafluoroethylene, and after heat preservation treatment at 95°C for 3h, it is cooled to 25°C and left standing for 10h. After being washed alternately with deionized water and anhydrous ethanol, vacuum drying at 75°C for 8h obtains the zinc oxide diatomite composite;

[0133] 2.1 2.1 parts by weight of zinc oxide diatomite compound and 6.2 parts by weight of sodium sulfide were dispersed in 50 parts by weight of deionized water, ultrasonic dispersion was carried out for 18 min, then reaction was carried out at 82°C under nitrogen protection for 2.7 h, after reaction, zinc sulfide diatomite compound was obtained by filtration, washing and vacuum drying in sequence;

[0134] 50 parts by weight of zinc sulfide diatomite compound and 0.40 parts by weight of n-octadecyl phosphate were dispersed in 500 parts by weight of ethanol, ultrasonic treatment was carried out at a power of 400 W for 60 min, then the solid was collected by centrifugation, washed with ethanol for several times, and then multi-stage microspheres were prepared by heat treatment at 115°C for 50 min.

[0135] Preparation Example 12:

[0136] The preparation method of the multi-stage microspheres comprises the following steps:

[0137] 20 parts by weight of diatomite were dispersed in 200 parts by weight of 10 wt% hydrochloric acid solution, reaction was carried out at 80°C for 4 h, after reaction, the activated diatomite was obtained by filtration, washing with deionized water until neutral, and then calcination at a temperature increasing rate of 5°C / min to 850°C for 3 h in a muffle furnace.

[0138] 2.2 parts by weight of zinc nitrate dihydrate were dispersed in 100 parts by weight of isopropyl alcohol, after stirring and dispersion at 85°C for 15 min, 1.4 parts by weight of triethylamine was added, stirring was continued for 15 min, then the mixture was cooled to 25°C and stood for 3 h to obtain a mixed solution;

[0139] 1.6 parts by weight of hexamethylenetetramine and 3.3 parts by weight of zinc nitrate hexahydrate were dispersed in 100 parts by weight of deionized water, stirring and dispersion were carried out at 25°C for 20 min to obtain a growth solution;

[0140] 50 parts by weight of activated diatomite were dispersed in the above-mentioned mixed solution, after soaking treatment for 15 min, the diatomite was washed with ethanol for several times, dried in an oven at 120°C for 1 h, and then stood at 25°C for 24 h to obtain a diatomite intermediate;

[0141] The above-mentioned diatomite intermediate and the growth solution were mixed and transferred into a high-temperature reaction kettle lined with polytetrafluoroethylene, after heat treatment at 100°C for 3 h, the mixture was cooled to 25°C and stood for 10 h, then washed with deionized water and anhydrous ethanol alternately, and finally vacuum dried at 75°C for 8 h to obtain a zinc oxide diatomite compound;

[0142] 2.2 parts by weight of zinc oxide diatomite compound and 6.3 parts by weight of sodium sulfide were dispersed in 50 parts by weight of deionized water, ultrasonic dispersion was carried out for 20 min, then reaction was carried out at 85°C under nitrogen protection for 3 h, after reaction, zinc sulfide diatomite compound was obtained by filtration, washing and vacuum drying in sequence;

[0143] 50 parts by weight of the zinc sulfide diatomite composite and 0.45 parts by weight of n-octadecyl phosphate were dispersed in 500 parts by weight of ethanol, and after ultrasonic treatment at a power of 400 W for 60 min, the solid was collected by centrifugation, washed with ethanol several times, and then heat-treated at 120℃ for 60 min to obtain the multi-stage microspheres.

[0144] Preparation Example 13:

[0145] The method for preparing the multi-stage microspheres comprises the following steps:

[0146] 20 parts by weight of diatomite was dispersed in 200 parts by weight of 10 wt% hydrochloric acid solution, and stirred at 80℃ for 4 h. After the reaction was completed, the product was filtered, washed with deionized water until neutral, and then calcined in a muffle furnace at a temperature increasing rate of 5℃ / min to 850℃ for 3 h to obtain activated diatomite;

[0147] 2.2 parts by weight of zinc nitrate dihydrate was dispersed in 100 parts by weight of isopropyl alcohol, and after stirring at 85℃ for 15 min, 1.4 parts by weight of triethylamine was added. After stirring for another 15 min, the mixture was cooled to 25℃ and left to stand for 3 h to obtain a mixed solution;

[0148] 1.6 parts by weight of hexamethylenetetramine and 3.3 parts by weight of zinc nitrate hexahydrate were dispersed in 100 parts by weight of deionized water, and stirred at 25℃ for 20 min to obtain a growth solution;

[0149] 50 parts by weight of the activated diatomite was dispersed in the above mixed solution, soaked for 15 min, washed with ethanol several times, dried in an oven at 120℃ for 1 h, and left to stand at 25℃ for 24 h to obtain a diatomite intermediate;

[0150] The diatomite intermediate and the growth solution were mixed and transferred into a high-temperature reaction kettle lined with polytetrafluoroethylene. After heat treatment at 100℃ for 3 h, the mixture was cooled to 25℃ and left to stand for 10 h. After washing with deionized water and anhydrous ethanol alternately, vacuum drying was performed at 75℃ for 8 h to obtain a zinc oxide diatomite composite;

[0151] 2.2 parts by weight of the zinc oxide diatomite composite and 6.3 parts by weight of sodium sulfide were dispersed in 50 parts by weight of deionized water, and ultrasonic dispersion was performed for 20 min. After stirring at 85℃ for 3 h in a nitrogen protection environment, the product was filtered, washed, and vacuum dried to obtain the multi-stage microspheres.

[0152] Preparation Example 14:

[0153] The method for preparing the multi-stage microspheres comprises the following steps:

[0154] 20 parts by weight of diatomite is dispersed in 200 parts by weight of 10wt% hydrochloric acid solution, and stirred at 80°C for 4h. After the reaction is completed, the diatomite is extracted by suction filtration, washed with deionized water until neutral, and then placed in a muffle furnace and heated to 850°C at a heating rate of 5°C / min for calcination for 3h to obtain activated diatomite.

[0155] 2.2 parts by weight of zinc nitrate dihydrate is dispersed in 100 parts by weight of isopropanol, and stirred at 85°C for 15min. Then, 1.4 parts by weight of triethylamine is added, and the mixture is stirred for another 15min, and then cooled to 25°C and left to stand for 3h to obtain a mixed solution.

[0156] 1.6 parts by weight of hexamethylenetetramine and 3.3 parts by weight of zinc nitrate hexahydrate are dispersed in 100 parts by weight of deionized water, and stirred at 25°C for 20min to obtain a growth solution.

[0157] 50 parts by weight of activated diatomite is dispersed in the above mixed solution, soaked for 15min, washed with ethanol several times, dried in an oven at 120°C for 1h, and left to stand at 25°C for 24h to obtain a diatomite intermediate.

[0158] The diatomite intermediate and the growth solution are mixed and transferred into a high-temperature reaction kettle lined with polytetrafluoroethylene. After being kept at 100°C for 3h, the mixture is cooled to 25°C and left to stand for 10h. After being washed with deionized water and anhydrous ethanol alternately, the mixture is vacuum dried at 75°C for 8h to obtain a zinc oxide diatomite composite.

[0159] 50 parts by weight of the zinc oxide diatomite composite and 0.45 parts by weight of n-octadecyl phosphate are dispersed in 500 parts by weight of ethanol, and ultrasonically treated at a power of 400W for 60min. The solid is collected by centrifugation, washed with ethanol several times, and heat-treated at 120°C for 60min to obtain multi-stage microspheres.

[0160] Preparation Example 15:

[0161] The method for preparing the activated diatomite comprises the following steps:

[0162] 20 parts by weight of diatomite is dispersed in 200 parts by weight of 10wt% hydrochloric acid solution, and stirred at 80°C for 4h. After the reaction is completed, the diatomite is extracted by suction filtration, washed with deionized water until neutral, and then placed in a muffle furnace and heated to 850°C at a heating rate of 5°C / min for calcination for 3h to obtain activated diatomite.

[0163] Example 1:

[0164] The method for preparing the environmentally friendly fluorine-free superhydrophobic coating material comprises the following steps:

[0165] 65 parts by weight of the hyperbranched polyurethane prepared in Preparation Example 1, 20 parts by weight of ethyl acetate, 14 parts by weight of propylene glycol methyl ether acetate were added into a reaction kettle, stirred at 500 r / min for 10 min at 25℃, 2 parts by weight of polydimethylsiloxane, 0.7 parts by weight of octadecyl isocyanate were added, stirred at 40℃ for 60 min, 4 parts by weight of the multi-stage microspheres prepared in Preparation Example 8 were ultrasonically treated at a power of 400 W for 15 min, 9 parts by weight of Isopar G, 2.6 parts by weight of isophorone diisocyanate, 0.6 parts by weight of silane coupling agent KH-560, 0.03 parts by weight of dibutyl tin dilaurate and 0.07 parts by weight of triethylenediamine were dispersed at a stirring speed of 2000 r / min for 30 min, and then passed through a 400-mesh screen to obtain the environmentally friendly fluorine-free super-hydrophobic coating material.

[0166] Example 2:

[0167] A method for preparing an environmentally friendly fluorine-free super-hydrophobic coating material includes the following steps:

[0168] 67 parts by weight of the hyperbranched polyurethane prepared in Preparation Example 2, 22 parts by weight of ethyl acetate, 14.5 parts by weight of propylene glycol methyl ether acetate were added into a reaction kettle, stirred at 500 r / min for 12 min at 25℃, 2.5 parts by weight of polydimethylsiloxane, 0.75 parts by weight of octadecyl isocyanate were added, stirred at 40℃ for 65 min, 4.5 parts by weight of the multi-stage microspheres prepared in Preparation Example 9 were ultrasonically treated at a power of 400 W for 17 min, 9.5 parts by weight of Isopar G, 2.7 parts by weight of isophorone diisocyanate, 0.65 parts by weight of silane coupling agent KH-560, 0.035 parts by weight of dibutyl tin dilaurate and 0.075 parts by weight of triethylenediamine were dispersed at a stirring speed of 2000 r / min for 35 min, and then passed through a 400-mesh screen to obtain the environmentally friendly fluorine-free super-hydrophobic coating material.

[0169] Example 3:

[0170] A method for preparing an environmentally friendly fluorine-free super-hydrophobic coating material includes the following steps:

[0171] 70 parts by weight of the hyperbranched polyurethane prepared in Preparation Example 3, 25 parts by weight of ethyl acetate, 15 parts by weight of propylene glycol methyl ether acetate were added into a reaction kettle, stirred at 500 r / min for 15 min at 25℃, 3 parts by weight of polydimethylsiloxane, 0.8 parts by weight of octadecyl isocyanate were added, stirred at 40℃ for 70 min, 5 parts by weight of the multi-stage microspheres prepared in Preparation Example 10 were ultrasonically treated at a power of 400W for 20 min, 10 parts by weight of Isopar G, 2.8 parts by weight of isophorone diisocyanate, 0.7 parts by weight of silane coupling agent KH-560, 0.04 parts by weight of dibutyl tin dilaurate and 0.08 parts by weight of triethylenediamine were dispersed by stirring at a rotating speed of 2000 r / min for 40 min, and then a fluorine-free environmentally friendly super-hydrophobic coating material was prepared by passing through a 400-mesh screen.

[0172] Example 4:

[0173] A preparation method of a fluorine-free environmentally friendly super-hydrophobic coating material includes the following steps:

[0174] 72 parts by weight of the hyperbranched polyurethane prepared in Preparation Example 4, 27 parts by weight of ethyl acetate, 15.5 parts by weight of propylene glycol methyl ether acetate were added into a reaction kettle, stirred at 500 r / min for 17 min at 25℃, 3.5 parts by weight of polydimethylsiloxane, 0.85 parts by weight of octadecyl isocyanate were added, stirred at 40℃ for 75 min, 5.5 parts by weight of the multi-stage microspheres prepared in Preparation Example 11 were ultrasonically treated at a power of 400W for 25 min, 10.5 parts by weight of Isopar G, 2.9 parts by weight of isophorone diisocyanate, 0.75 parts by weight of silane coupling agent KH-560, 0.045 parts by weight of dibutyl tin dilaurate and 0.085 parts by weight of triethylenediamine were dispersed by stirring at a rotating speed of 2000 r / min for 45 min, and then a fluorine-free environmentally friendly super-hydrophobic coating material was prepared by passing through a 400-mesh screen.

[0175] Example 5:

[0176] A preparation method of a fluorine-free environmentally friendly super-hydrophobic coating material includes the following steps:

[0177] 75 parts by weight of the hyperbranched polyurethane prepared in Preparation Example 5, 30 parts by weight of ethyl acetate, 16 parts by weight of propylene glycol methyl ether acetate were added into a reaction kettle, and stirred at 500 r / min for 20 min at 25℃, 4 parts by weight of polydimethylsiloxane, 0.9 parts by weight of octadecyl isocyanate were added, and stirred at 40℃ for 80 min, 6 parts by weight of the multi-stage microspheres prepared in Preparation Example 12 were ultrasonically treated at a power of 400W for 30 min, 11 parts by weight of Isopar G, 3.0 parts by weight of isophorone diisocyanate, 0.8 parts by weight of silane coupling agent KH-560, 0.05 parts by weight of dibutyl tin dilaurate and 0.09 parts by weight of triethylenediamine were dispersed by stirring at a rotation speed of 2000 r / min for 50 min, and then a 400-mesh screen was used to prepare an environmentally friendly fluorine-free super-hydrophobic coating material.

[0178] Comparative Example 1:

[0179] A preparation method of an environmentally friendly fluorine-free super-hydrophobic coating material includes the following steps:

[0180] The hyperbranched polyurethane prepared in Preparation Example 5 in Example 5 was replaced by the hyperbranched polyurethane prepared in Preparation Example 6, and the other operations were consistent with Example 5.

[0181] Comparative Example 2:

[0182] A preparation method of an environmentally friendly fluorine-free super-hydrophobic coating material includes the following steps:

[0183] The hyperbranched polyurethane prepared in Preparation Example 5 in Example 5 was replaced by the modified polyurethane prepared in Preparation Example 7, and the other operations were consistent with Example 5.

[0184] Comparative Example 3:

[0185] A preparation method of an environmentally friendly fluorine-free super-hydrophobic coating material includes the following steps:

[0186] The multi-stage microspheres prepared in Preparation Example 12 in Example 5 were replaced by the multi-stage microspheres prepared in Preparation Example 13, and the other operations were consistent with Example 5.

[0187] Comparative Example 4:

[0188] A preparation method of an environmentally friendly fluorine-free super-hydrophobic coating material includes the following steps:

[0189] The multi-stage microspheres prepared in Preparation Example 12 in Example 5 were replaced by the multi-stage microspheres prepared in Preparation Example 14, and the other operations were consistent with Example 5.

[0190] Comparative Example 5:

[0191] A preparation method of an environmentally friendly fluorine-free super-hydrophobic coating material includes the following steps:

[0192] The multistage microspheres prepared in Preparation Example 12 in Example 5 were replaced with the activated diatomite prepared in Preparation Example 15, and other operations were consistent with those in Example 5.

[0193] Comparative Example 6:

[0194] A preparation method of an environmentally friendly fluorine-free superhydrophobic coating material comprises the following steps:

[0195] The 6 parts by weight of the multistage microspheres prepared in Preparation Example 12 in Example 5 were replaced with 2 parts by weight of the multistage microspheres prepared in Preparation Example 12, and other operations were consistent with those in Example 5.

[0196] Comparative Example 7:

[0197] A preparation method of an environmentally friendly fluorine-free superhydrophobic coating material comprises the following steps:

[0198] The 6 parts by weight of the multistage microspheres prepared in Preparation Example 12 in Example 5 were replaced with 15 parts by weight of the multistage microspheres prepared in Preparation Example 12, and other operations were consistent with those in Example 5.

[0199] Performance test:

[0200] The superhydrophobic coating materials prepared in Examples 1-5 and Comparative Examples 1-7 were respectively sprayed onto the surface of a stainless steel substrate, and were naturally cured at room temperature for 24 hours to obtain superhydrophobic coatings, the thickness of the superhydrophobic coatings was 100 μm, and the water contact angle thereof was tested by a contact angle measuring instrument;

[0201] Abrasion resistance test: a weight of 500 g was pressed on a 600-mesh sandpaper to abrade the superhydrophobic coatings prepared in Examples 1-5 and Comparative Examples 1-7, respectively, the fixed friction distance was 20 cm each time, which was recorded as one cycle, and the water contact angle was tested after polishing for 100 times;

[0202] Self-repairing test: the same length of scratches were drawn on the superhydrophobic coatings prepared in Examples 1-5 and Comparative Examples 1-7, respectively, and were placed in a 70℃ environment for treatment, and the self-repairing time was recorded, and the test results are shown in Table 1.

[0203] Table 1. Performance test of environmentally friendly fluorine-free superhydrophobic coating

[0204]

[0205] According to the test results in Table 1, it can be observed that Examples 1-5 have good superhydrophobicity, self-repairing performance and abrasion resistance, while the coating performance prepared in Comparative Examples 1-7 is reduced.

[0206] The reason for the performance reduction of Comparative Example 1 can be that the dynamic borate ester bond and the catechol structure are missing, and self-repair cannot be achieved; the dynamic borate ester bond can affect the stress dissipation capacity, thereby affecting the wear resistance of the coating; the reason for the performance reduction of Comparative Example 2 can be that the modified polyurethane does not have a hyperbranched structure, affecting the elasticity and flexibility of the coating, resulting in a decrease in wear resistance; the activity of the molecular chain can be reduced, thereby prolonging the self-repair time; the reason for the performance reduction of Comparative Example 3 can be that the multi-level microspheres are not treated with n-octadecyl phosphate, which provides low surface energy, and its absence leads to a sharp decrease in water contact angle; high surface energy can make water more easily penetrate into microcracks, accelerating the failure of the coating and affecting its wear resistance; the reason for the performance reduction of Comparative Example 4 can be that the zinc oxide is not converted into zinc sulfide, and the zinc oxide is prone to hydrolysis in a humid environment, destroying the surface rough structure and reducing the water contact angle; the reason for the performance reduction of Comparative Example 5 can be that the zinc oxide or zinc sulfide is not loaded on the diatomite, and the multi-level microspheres do not have a layered rough structure, but rely on the polyurethane matrix, which completely loses its superhydrophobicity; without the enhancement of multi-level microspheres, the wear resistance is reduced; the dynamic bond can repair the matrix scratches, but cannot establish a hydrophobic surface; the reason for the performance reduction of Comparative Example 6 can be that the amount of multi-level microspheres is too small, and insufficient amount is difficult to form a continuous air cushion structure, and the protection of the matrix by the microspheres is insufficient, thereby affecting the wear resistance; the reason for the performance reduction of Comparative Example 7 can be that the amount of multi-level microspheres is too large, and excessive multi-level microspheres hinder the crosslinking of polyurethane, the compactness of the coating decreases, and the contact angle significantly decreases after friction; the multi-level microspheres agglomerate into stress concentration points, accelerating the peeling of the coating, and reducing the wear resistance; the cracks expand at the agglomeration of the microspheres, and the self-repair efficiency is reduced.

[0207] The above-described embodiments detail the technical solutions and beneficial effects of the present application, and it should be understood that the above-described embodiments are only specific embodiments of the present application and are not intended to limit the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application.

Claims

1. A method for preparing an environmentally friendly, fluorine-free, superhydrophobic coating material, characterized in that, The preparation method includes the following steps: After mixing hyperbranched polyurethane, ethyl acetate, and propylene glycol methyl ether acetate for 10-20 min, polydimethylsiloxane and octadecyl isocyanate were added and reacted for 60-80 min. After adding multi-level microspheres and ultrasonically treating for 15-30 min, IsoparG, isophorone diisocyanate, silane coupling agent KH-560, dibutyltin dilaurate, and triethylenediamine were added and stirred and dispersed for 30-50 min to obtain the environmentally friendly fluorine-free superhydrophobic coating material. The preparation method of the hyperbranched polyurethane includes the following steps: The first intermediate is obtained by reacting 3,4-dihydroxybenzoic acid and allyl borate pinacol ester together. The first intermediate, hydroxyethyl methacrylate, EDC and DMAP are mixed and reacted to obtain the second intermediate; The modified borate ester was obtained by mixing the second intermediate, β-mercaptoethanol and 2,2-dimethoxy-phenylacetophenone and treating it with 395nm LED light source. After mixing trimethylolpropane, dimethylolpropionic acid and isophorone diisocyanate for 30-50 min, dibutyltin diacetate was added and the mixture was reacted to obtain the first intermediate system. The first intermediate system and the modified borate ester were mixed and reacted to obtain the second intermediate system; After the second intermediate system and the hydroxyl-terminated polydimethylsiloxane are mixed and reacted for 3-5 hours, triethylamine is added and the mixture is reacted for 30-60 minutes, and then deionized water is added and the mixture is reacted for 40-60 minutes to obtain the hyperbranched polyurethane. The method for preparing the multi-level microspheres includes the following steps: Activated diatomaceous earth is obtained by mixing and stirring diatomaceous earth with 10wt% hydrochloric acid solution, followed by high-temperature calcination. Zinc nitrate dihydrate and triethylamine were mixed to obtain a mixed solution; The growth solution is obtained by mixing hexamethylenetetramine and zinc nitrate hexahydrate; Activated diatomaceous earth is dispersed in a mixed solution and soaked for 5-15 minutes to obtain diatomaceous earth intermediates; The zinc oxide diatomite complex was obtained by mixing and reacting the diatomite intermediate with the growth solution. Zinc oxide diatomite composite and sodium sulfide are mixed and reacted to obtain zinc sulfide diatomite composite; The multi-level microspheres were prepared by reacting zinc sulfide diatomaceous earth composite with octadecyl phosphate.

2. The preparation method of the environmentally friendly fluorine-free superhydrophobic coating material as described in claim 1, characterized in that, The weight ratio of the second intermediate, β-mercaptoethanol, and 2,2-dimethoxy-phenylacetophenone is 5~7:2.5~3.5:0.05~0.

1.

3. The preparation method of the environmentally friendly fluorine-free superhydrophobic coating material as described in claim 1, characterized in that, The weight ratio of trimethylolpropane, dimethylolpropionic acid, isophorone diisocyanate, dibutyltin diacetate, modified borate ester, hydroxyl-terminated polydimethylsiloxane, triethylamine, and deionized water is 5.5~7.5:3~5:20~25:0.015~0.03:6~8:6.5~8.5:2~4:140~160.

4. The preparation method of the environmentally friendly fluorine-free superhydrophobic coating material as described in claim 1, characterized in that, The conditions for high-temperature calcination include a calcination temperature of 800~850℃ and a calcination time of 2~3h.

5. The preparation method of the environmentally friendly fluorine-free superhydrophobic coating material as described in claim 1, characterized in that, The weight ratio of the activated diatomaceous earth, zinc nitrate dihydrate, triethylamine, hexamethylenetetramine, and zinc nitrate hexahydrate is 50:1.8~2.2:1.2~1.4:1.4~1.6:2.9~3.

3.

6. The method for preparing an environmentally friendly, fluorine-free, superhydrophobic coating material as described in claim 1, characterized in that, The weight ratio of the zinc oxide diatomite composite to sodium sulfide is 1.8~2.2:5.9~6.

3.

7. The method for preparing an environmentally friendly, fluorine-free, superhydrophobic coating material as described in claim 1, characterized in that, The weight ratio of the hyperbranched polyurethane, ethyl acetate, propylene glycol methyl ether acetate, polydimethylsiloxane, octadecyl isocyanate, multi-level microspheres, Isopar G, isophorone diisocyanate, silane coupling agent KH-560, dibutyltin dilaurate, and triethylenediamine is 65~75:20~30:14~16:2~4:0.7~0.9:4~6:9~11:2.6~3.0:0.6~0.8:0.03~0.05:0.07~0.

09.

8. An environmentally friendly, fluorine-free, superhydrophobic coating material, characterized in that, The material is prepared by any one of the environmentally friendly fluorine-free superhydrophobic coatings described in claims 1 to 7.

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