Abstract
A method comprises: dispersing a nanoparticle sol, ammonia water and a waterborne hydrophobic treatment agent in deionized water to prepare a modified nanoparticle suspension, and obtaining a superhydrophobic modified nanoparticle powder by means of a spray drying process; and adding a porous ceramic micro-powder and a waterborne silane coupling agent into deionized water, then adding the superhydrophobic modified nanoparticle powder, performing constant stirring to prepare a superhydrophobic particle impregnating porous particle suspension, and obtaining the impregnated porous powder with superhydrophobic particles by means of a filter drying process or the spray drying process.
Claims
1. A method for preparing an impregnated porous powder with superhydrophobic particles, comprising the following steps: i) dispersing 1-12 parts by mass of a nanoparticle sol, 2-10 parts by mass of ammonia water and 1-2 parts by mass of a waterborne hydrophobic treatment agent in 60-100 parts by mass of deionized water and performing constant stirring for 12-48 h to prepare a modified nanoparticle suspension, and obtaining a superhydrophobic modified nanoparticle powder by means of a spray drying process, wherein the nanoparticle sol is at least one of an aluminum oxide nanoparticle sol, a titanium dioxide nanoparticle sol and a silicon dioxide nanoparticle sol with a particle size of 1-200 nm, a solid content of 15-30 wt. % and a pH value of 8-9; and the waterborne hydrophobic treatment agent is one of a waterborne perfluorodecyl siloxane oligomer or a waterborne propyloctyl siloxane oligomer or an emulsion formed by mixing alkyl siloxane with a cationic or nonionic perfluoroacrylic surfactant, a mixing mass ratio of alkyl siloxane to the surfactant is (1-3):1; and ii) adding 1-18 parts by mass of a porous ceramic micro-powder and 0.1-0.5 part by mass of a waterborne silane coupling agent into 60-100 parts by mass of deionized water or adding 1-18 parts by mass of a porous micron ceramic powder, 2-10 parts by mass of ammonia water, 0.4-1 part by mass of a waterborne hydrophobic treatment agent and 0.1-0.5 part by mass of a waterborne silane coupling agent into 60-100 parts by mass of deionized water, performing constant stirring for 12-48 h, then adding 1-5 parts by mass of the superhydrophobic modified nanoparticle powder obtained in the step (1), and performing constant stirring for 12-48 h to prepare a superhydrophobic particle impregnating porous particle suspension, and obtaining the impregnated porous powder with superhydrophobic particles by means of a filter drying process or the spray drying process, wherein the waterborne silane coupling agent is Evonik DynasylanHydrosil 1151 amino waterborne siloxane, and the porous ceramic micro-powder is at least one of diatomite particles, silicon dioxide particles, aluminum oxide particles and zirconium oxide particles with a particle size of 1-75 m, or porous ceramic particles prepared by performing high-temperature sintering by taking the diatomite particles, silicon dioxide particles, aluminum oxide particles and zirconium oxide particles as a raw material.
2. The method according to claim 1, wherein the nanoparticle sol is at least one of the aluminum oxide nanoparticle sol, the titanium dioxide nanoparticle sol and the silicon dioxide nanoparticle sol with a particle size of 1-200 nm, a solid content of 15-30 wt. % and a pH value of 8-9; and the modified nanoparticle suspension can further be one of nanoparticle emulsions containing polytetrafluoroethylene, polystyrene, polypropylene or high density polyethylene with a solid content of 30 wt. % and a pH value of 8-9.
3. The method according to claim 1, wherein the filter drying refers to suction filtration of the porous particle suspension under a condition of a vacuum degree of 0.02 MPa or centrifugal separation of the porous particle suspension at a rotating speed of 6000 rpm, and drying of filtered slurry for 1-2 h at 80-120° C.; and the spray drying process refers to spray drying for 1-2 h under conditions of an inlet temperature of 160-220° C., a spraying air pressure of 0.3 Mpa and a moisture evaporation capacity of 1-200 L/h.
4. The method according to claim 1, wherein the waterborne perfluorodecyl siloxane is Evonik Dynasylan F8815, the waterborne propyloctyl siloxane oligomer is Evonik Protectosil WS 670, alkyl siloxane can be any one of tridecafluorotriethoxy silane, isobutyltriethoxy silane or proyltriethoxy silane, and the waterborne silane coupling agent is Evonik DynasylanHydrosil 1151 amino waterborne silane.
5. The method according to claim 1, wherein the porous ceramic micro-powder is flaky, columnar, disciform or spherical with a pore diameter of 20 nm to 2 m, a specific surface area of 40-200 m.sup.2/g and a pore volume of 0.08-1.2 cm.sup.3/g.
6. The method according to claim 5, wherein the particle size is 1-75 m, the specific surface area is 10-80 m.sup.2/g and the pore volume is 0.02-0.6 cm.sup.3/g, and the dried powder is hydrophilic and is superhydrophobic if being heated for 1-2 h at 150-250° C.
7. A process for preparing paint or coatings comprising a step of using the impregnated porous powder with superhydrophobic particles of claim 6 in preparation of the paint or coatings.
8. The process according to claim 7, wherein the process further comprising the following preparation steps: i) oily or waterborne paint: mechanically stirring and dispersing 0.1-10 parts by mass of an impregnated porous powder with superhydrophobic particles in 10-30 parts by mass of a volatile organic solvent or deionized water; upon preparation of the waterborne paint: directly using 1-40 parts by mass of an impregnated porous powder with superhydrophobic particles, then adding 2-10 parts by mass of a film forming matter, 1-4 parts by mass of a curing agent and 0.05-0.4 part by mass of an acrylate copolymer as a dispersant, 0.1-0.5 part by mass of an adhesion promoter, 0.1-0.5 part by mass of a silane coupling agent and 0.1-0.5 part by mass of propylene glycol methyl ether acetate as a stabilizer, and mechanically stirring the mixture for 10 min to obtain the superhydrophobic paint; and coating any cleaned substrate surface with the superhydrophobic coating by way of spraying, dip-coating, roller coating or brush coating, and placing the substrate in an oven at 150-250° C. to be heated and dried for 1-2 h to obtain a superhydrophobic coating, wherein the volatile organic solvent is at least one of ketone, alcohol, ester, fluorocarbon and ether; the film forming matter is at least one of a fluorocarbon resin with low surface energy, organic silicon and a modified resin thereof or a non-hydrophobic acrylic resin, epoxy resin, polyurethane resin, ceramic bond, waterborne acrylic resin or waterborne polyurethane resin; the adhesion promoter is at least one of amino siloxane, alkyl siloxane or a methyl siloxy copolymerized resin; the acrylate copolymer is at least one of polyacrylate, an alkyl acrylate copolymer and an acrylate-acrylic acid copolymer; one end of the silane coupling agent is amino and the other end thereof is ethoxyl or methoxyl; and the curing agent is at least one of isocyanate, fatty amine, aromatic amine and acylamino amine; ii) powder paint: putting 0.1-10 parts by mass of a impregnated porous powder with superhydrophobic particles and 2-8 parts by mass of a binder powder in a ball mill to be ball-milled, putting the powders into a mold to be heated and melted, and performing pulverization for 5-10 min by using a multifunctional pulverizer after cooling to obtain superhydrophobic powder paint with a size of 15-48 m; and electrostatically spraying the prepared powder to a metal substrate, putting the metal substrate in the oven to be cured at a high temperature of 150-250° C. for 10-20 min, and cooling the metal substrate to room temperature to obtain the superhydrophobic coating, wherein the binder powder is at least one of a polyester resin powder, an epoxy resin powder, a polyurethane resin powder and a fluorocarbon resin powder, and the ball milling refers to putting the mixed powders in a ball-milling tank, then adding zirconium oxide ball-milling beads with particle sizes of 1-1.4 mm and performing ball-milling for 4-12 h with a rotating speed of the ball mill being kept at 30-300 r/min; and iii) electrophoretic paint: diluting 2-10 parts by mass of electrophoretic paint 5-10 times with deionized water, adding 0.1-10 parts by mass of an impregnated porous powder with superhydrophobic particles into the solution by taking 0.05-0.4 part by mass of an acrylate copolymer as a dispersant, mechanically stirring the solution for 30 min, performing electrophoretic deposition for 10-30 min at a condition of a direct current voltage of 30-40 V, and then putting the mixture in the oven at 150-250° C. to be heated and dried for 1-2 h to obtain the superhydrophobic coating, wherein the electrophoretic paint is at least one of epoxy electrophoretic paint, acrylic electrophoretic paint and polyurethane electrophoretic paint; and the acrylate copolymer is at least one of polyacrylate, an alkyl acrylate copolymer and an acrylate-acrylic acid copolymer.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1a shows macroscopic photographs of suspensions of impregnated porous particles with superhydrophobic particles;
[0020] FIG. 1b shows a schematic diagram of the spray drying device;
[0021] FIG. 1c shows one example of macroscopic wettability of original porous particles compared with the impregnated porous particles with superhydrophobic particles, which are spray-dried and roasted at a high temperature of 200° C.;
[0022] FIG. 1d shows another example of macroscopic wettability of original porous particles compared with the impregnated porous particles with superhydrophobic particles, which are spray-dried and roasted at a high temperature of 200° C.;
[0023] FIG. 2a shows a macroscopic wettability of a room temperature cured coating prepared by applying the impregnated porous powder with superhydrophobic particles (nanoparticles are aluminum oxide and microporous particles are porous ceramic particles sintered at high temperature);
[0024] FIG. 2b shows a contact angle of a room temperature cured coating prepared by applying the impregnated porous powder with superhydrophobic particles (nanoparticles are aluminum oxide and microporous particles are porous ceramic particles sintered at high temperature);
[0025] FIG. 2c shows a macroscopic wettability of a high temperature cured coating prepared by applying the impregnated porous powder with superhydrophobic particles (nanoparticles are aluminum oxide and microporous particles are porous ceramic particles sintered at high temperature);
[0026] FIG. 2d shows a contact angle of a high temperature cured coating prepared by applying the impregnated porous powder with superhydrophobic particles (nanoparticles are aluminum oxide and microporous particles are porous ceramic particles sintered at high temperature);
[0027] FIG. 3a shows a macroscopic morphology and wettability of a superhydrophobic coating prepared by applying an impregnated porous particle porous powder with superhydrophobic particles (nanoparticles are silicon dioxide and microporous particles are porous ceramic particles sintered at high temperature): macroscopic wettability of a high temperature cured superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles;
[0028] FIG. 3b shows a macroscopic morphology and wettability of a superhydrophobic coating prepared by applying an impregnated porous particle porous powder with superhydrophobic particles (nanoparticles are silicon dioxide and microporous particles are porous ceramic particles sintered at high temperature): a contact angle of the coating;
[0029] FIG. 3c shows a macroscopic morphology and wettability of a superhydrophobic coating prepared by applying an impregnated porous particle porous powder with superhydrophobic particles (nanoparticles are silicon dioxide and microporous particles are porous ceramic particles sintered at high temperature): a roll-off angle of the coating;
[0030] FIG. 4a is SEM diagrams after and before the impregnated porous particle porous powder with superhydrophobic particles is impregnated: originally high temperature sintered porous ceramic particles;
[0031] FIG. 4b is SEM diagrams after and before the impregnated porous particle porous powder with superhydrophobic particles is impregnated: a morphology of a hole thereof amplified;
[0032] FIG. 4c is SEM diagrams after and before the impregnated porous particle porous powder with superhydrophobic particles is impregnated: a surface structural diagram of the applied superhydrophobic coating after the impregnated porous powder with superhydrophobic particles is prepared;
[0033] FIG. 4d is SEM diagrams after and before the impregnated porous particle porous powder with superhydrophobic particles is impregnated: a morphology of the amplified hole of the impregnated porous particle porous powder with superhydrophobic particles at the time;
[0034] FIG. 5a is a surface SEM diagram after mechanical durability and wear of the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles: a variation diagram of a contact angle and a rolling angel of the coating along with a Taber abrasion period
[0035] FIG. 5b is a surface SEM diagram after mechanical durability and wear of the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles: a surface morphology diagram of the coating after 1000 abrasion periods (NEM is a superhydrophobic granular porous powder, FEVE is a fluorocarbon resin, epoxy is an epoxy resin, ceramic paint is a ceramic coating, and a load is 1 kg);
[0036] FIG. 6a shows a surface and section structural diagrams of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a surface morphology;
[0037] FIG. 6b shows a surface and section structural diagrams of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a section morphology, and an illustration is a TEM diagram of the particles impregnating in the porous structure;
[0038] FIG. 7a shows SEM diagrams and pore volume variation diagrams applying the impregnated porous powder with superhydrophobic particles before and after impregnating: the SEM diagram of the porous ceramic powder without load;
[0039] FIG. 7b shows SEM diagrams and pore volume variation diagrams applying the impregnated porous powder with superhydrophobic particles before and after impregnating: the SEM diagram after impregnating the porous ceramic powder;
[0040] FIG. 7c shows SEM diagrams and pore volume variation diagrams applying the impregnated porous powder with superhydrophobic particles before and after impregnating: a diagram of the pore volume with different modified nanoparticle powder impregnating amounts varying along with pore diameter; a mechanical performance diagram of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles;
[0041] FIG. 8a shows microscopic mechanical performance of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a surface morphology of the coating scraped under 10 mN load in a microscopic scale;
[0042] FIG. 8b shows microscopic mechanical performance of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a surface morphology of the coating scraped under 100 mN load in a microscopic scale;
[0043] FIG. 9a shows wear resistance of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a contact angle and a roll-off angle of a highly wear-resistant normal temperature cured primer superhydrophobic coating by integrating superhydrophobic particles and primer a preparation method previously (a compare document CN110003735 A) after Taber abrasion;
[0044] FIG. 9b shows wear resistance of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: wear resistance of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles under a same test condition;
[0045] FIG. 9c shows wear resistance of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles subjected to tests under different severe conditions including RCA tape wearing, sand ablation, high-pressure water jet impact, high speed sandy water ablation and salt solution immersion (FEVE is a fluorocarbon resin with a 1 kg load);
[0046] FIG. 10a shows the universality of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: wear resistance of a superhydrophobic coating prepared by an epoxy resin adhesive;
[0047] FIG. 10b shows the universality of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: wear resistance of a superhydrophobic coating prepared by a ceramic coating adhesive;
[0048] FIG. 10c shows the universality of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: wear resistance of a superhydrophobic coating prepared by an acrylic resin adhesive (NEM@FEVE, NEM@epoxy, NEM@ceramica coating and NEM@acrylic are superhydrophobic coatings applying the impregnated porous powder with superhydrophobic particles prepared by different adhesives, Diatomite@FEVE, Nano-silica@FEVE, Mixed-silica@FEVE and Ultra-ever dry are comparative superhydrophobic coatings, FEVE is a fluorocarbon resin, epoxy is an epoxy resin, ceramic coating is ceramic paint and acrylic is an acrylic resin);
[0049] FIG. 11a shows an FTIR (Fourier Transform Infrared Spectrometer) of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles, the impregnated porous powder with superhydrophobic particles and the fluorocarbon resin as well as fluorine contents and hydroxyl contents of a superhydrophobic nanopowder, a microporous powder with a low modification degree and the impregnated porous powder with superhydrophobic particles: an FTIR infrared spectrogram;
[0050] FIG. 11b shows an FTIR (Fourier Transform Infrared Spectrometer) of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles, the impregnated porous powder with superhydrophobic particles and the fluorocarbon resin as well as fluorine contents and hydroxyl contents of a superhydrophobic nanopowder, a microporous powder with a low modification degree and the impregnated porous powder with superhydrophobic particles: a diagram of fluorine contents and hydroxyl contents;
[0051] FIG. 12a is a mechanical performance diagram of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a stress-strain curve;
[0052] FIG. 12b is a mechanical performance diagram of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a morphologic diagram of the stretched superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles;
[0053] FIG. 12c is a mechanical performance diagram of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a nanoindentation curve (NEM@FEVE is the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles, Diatomite@FEVE, Nano-silica@FEVE and Mixed-silica@FEVE are comparative superhydrophobic coatings, and FEVE is the fluorocarbon resin);
[0054] FIG. 13a is an adhesive strength diagram of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a normal adhesive strength diagram;
[0055] FIG. 13b is an adhesive strength diagram of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a tangential adhesive strength diagram;
[0056] FIG. 13c is an adhesive strength diagram of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a grid test schematic diagram;
[0057] FIG. 13d is an adhesive strength diagram of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a grid test result of the superhydrophobic coating (NEM@FEVE is the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles, Diatomite@FEVE, Nano-silica@FEVE and Mixed-silica@FEVE are comparative superhydrophobic coatings, and FEVE is the fluorocarbon resin);
[0058] FIG. 14a shows a scale prevention property of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a macroscopic picture of cement slurry solidified on a surface of the coating;
[0059] FIG. 14b shows a scale prevention property of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a macroscopic photo after the cement slurry on the surface of the coating falls off,
[0060] FIG. 15a shows an anti-condensation property of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: an integrated microscopic picture;
[0061] FIG. 15b shows an anti-condensation property of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a macroscopic photo;
[0062] FIG. 16a shows a frosting prevention property of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: an integrated frost layer growth process microscopically;
[0063] FIG. 16b shows a frosting prevention property of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: an integrated frost melting process microscopically, c is a macroscopic frost layer growth process, and d is a macroscopic frost layer melting process;
[0064] FIG. 16c shows a frosting prevention property of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a macroscopic frost layer growth process;
[0065] FIG. 16d shows a frosting prevention property of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a macroscopic frost layer melting process;
[0066] FIG. 17a shows a dropwise condensation property of hot water vapor of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: wherein a is a hot water vapor condensation test setting schematic diagram (a steam temperature is 100° C.);
[0067] FIG. 17b shows a dropwise condensation property of hot water vapor of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: an optical photo of a time-varying hot water vapor induced condensation behavior;
[0068] FIG. 17c shows a dropwise condensation property of hot water vapor of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: variations of the contact angle and the roll-off angle along with the hot water vapor condensation test time of the coating after Taber abrasion (the abrasion period is 200 cycles and the load is 1 kg);
[0069] FIG. 17d shows a dropwise condensation property of hot water vapor of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: an optical photo of the time-varying condensation behavior of the abraded coating after 200 cycles of Taber abrasion (the load is 1 kg);
[0070] FIG. 18a shows a neutral salt resisting effect of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a macroscopic photo of different coatings through a neutral salt test;
[0071] FIG. 18b shows a neutral salt resisting effect of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a macroscopic morphology of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles after the neutral salt test in 5000 h (i-iv are the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles prepared by different adhesives, v and vi are fluorocarbon resin and epoxy resin coatings, and vii-ix are comparative superhydrophobic coatings);
[0072] FIG. 19a shows a salt solution immersion prevention test of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: low frequency modulus of impedance of different coatings subjected to salt solution immersion;
[0073] FIG. 19b shows a salt solution immersion prevention test of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a variation of the low frequency modulus of impedance of different coatings along with salt solution immersion time;
[0074] FIG. 19c shows a salt solution immersion prevention test of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a variation of an open circuit potential of different coatings along with salt solution immersion time (NEM@FEVE and NEM@epoxy are superhydrophobic coatings applying the impregnated porous powder with superhydrophobic particles prepared by different adhesives, Diatomite@FEVE and Ultra-ever dry are comparative superhydrophobic coatings, FEVE is the fluorocarbon resin coating, and epoxy is an epoxy resin coating);
[0075] FIG. 20a is macroscopic morphologic diagrams of an anti-corrosive hydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles prepared by a wet spraying process after and before salt spray corrosion: a macroscopic morphology of an initial anti-corrosive hydrophobic coating;
[0076] FIG. 20b is macroscopic morphologic diagrams of an anti-corrosive hydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles prepared by a wet spraying process after and before salt spray corrosion: a macroscopic morphology of an anti-corrosive hydrophobic coating after 5000 h;
[0077] FIG. 21a shows performance of an air-conditioning heat exchanger of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a defrosting process photo of a superhydrophobic coating heat exchanger applying the impregnated porous powder with superhydrophobic particles and a commercial hydrophilic heat exchanger;
[0078] FIG. 21b shows performance of an air-conditioning heat exchanger of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: variations of defrosting energy consumptions of a superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles, a nanoparticle coating and a hydrophilic coating heat exchanger along with time;
[0079] FIG. 21c shows performance of an air-conditioning heat exchanger of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: an improved proportion of efficiency of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles compared with that of the hydrophilic coating heat exchanger under various working conditions, the various working conditions including condensation, dust contamination, frosting and defrosting;
[0080] FIG. 21d shows performance of an air-conditioning heat exchanger of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a frosting heat exchange amount of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles and the nanoparticle coating heat exchanger after dust blowing;
[0081] FIG. 21e shows performance of an air-conditioning heat exchanger of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: a defrosting energy consumption of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles and the nanoparticle coating heat exchanger after dust blowing;
[0082] FIG. 21f shows performance of an air-conditioning heat exchanger of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles: efficiency attenuation proportions of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles and the nanoparticle coating heat exchanger after dust blowing.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Example 1
[0083] In the embodiment, inorganic nanoparticles are aluminum oxide, a solvent is water, a hydrophobic modifier is a waterborne propyloctyl siloxane oligomer Evonik Protectosil WS 670, and porous microparticles are high-temperature sintered porous ceramic particles by taking aluminum oxide and silicon dioxide as a raw material. The preparation method includes the following preparation steps:
[0084] 10 parts by mass of a nano aluminum oxide sol, 5 parts by mass of ammonia water and 1.6 parts by mass of a waterborne propyloctyl siloxane oligomer Evonik Protectosil WS 670 were added into 100 parts by mass of deionized water to be continuously stirred for 24 h to obtain a modified nanoparticle suspension;
[0085] the nanoparticle suspension prepared in the step (1) was subjected to spray drying for 1-2 h under conditions of an inlet temperature of 160-220° C., a spray pressure of 0.3 Mpa and a water-evaporation capacity of 1-200 L/h to remove deionized water so as to obtain a nanoparticle powder;
[0086] 9 parts by mass of porous ceramic particles prepared by high temperature sintering and 0.2 part by mass of Evonik DynasylanHydrosil 1151 amino waterborne siloxane were added into 80 parts by mass of deionized water to be stirred for 12 h and then the modified nano powder prepared in the step (2) was added into the mixture to be continuously stirred for 12 h to prepare an impregnated porous powder with superhydrophobic particles suspension, and then the suspension was subjected to spray drying for 1-2 h under conditions of an inlet temperature of 160-220° C., a spraying air pressure of 0.3 Mpa and a moisture evaporation capacity of 1-200 L/h to obtain a final impregnated porous powder with superhydrophobic particles;
[0087] 6 parts by mass of the impregnated porous powder with superhydrophobic particles was mechanically stirred and dispersed in 25 parts by mass of water, then 8 parts by mass of waterborne epoxy resin, 0.4 part by mass of polyacrylate as a dispersant, 0.5 part by mass of amino siloxane and 0.4 part by mass of propylene glycol methyl ether acetate as a stabilizer were added, and the mixture was stirred for 10 min to obtain paint applying the porous powder; and
[0088] the paint applying the porous powder prepared in the step (4) was coated to a cleaned surface of any substrate, and the substrate was placed in a 200° C. oven to be heated and dried for 1 h to obtain the superhydrophobic coating.
[0089] FIG. 1a shows that the impregnated porous powder with superhydrophobic particles suspension is a white suspension, after the power subjected to spray drying is dried at a high temperature, a water drop dyed by methyl blue is spherical on the surface thereof, and compared with an original powder, excellent superhydrophobicity obtained after modification is shown as FIG. 1d; and FIG. 2a-d shows wettability conditions of the coating after room temperature curing and high temperature curing, it can be seen that the coating is hydrophilic when being subjected to room temperature curing, and benefited from breakdown of hydrophilic components at the high temperature, the coating subjected to high temperature curing obtains superhydrophobicity. The contact angle of the water drop on the surface of the coating is greater than 1550 and the roll-off angle is smaller than 5°; and the surface of the coating is continuous, even and intact and is free of defects of nodules, shrinkage cavities, bubbles, pinholes, cracks, peeling, pulverizing, sagging, base exposing, dirt inclusion and the like.
Example 2
[0090] In the embodiment, inorganic nanoparticles are silicon dioxide, a volatile organic solvent is propylene glycol methyl ether, a waterborne hydrophobic treatment agent is waterborne perfluorodecyl siloxane, and porous microparticles are high-temperature sintered porous ceramic particles by taking silicon dioxide, aluminum oxide and zirconium oxide as a raw material. The preparation method includes the following preparation steps:
[0091] 8 parts by mass of a nano silicon sol, 4 parts by mass of ammonia water and 0.5 part by mass of perfluoroalkyl siloxane were dispersed in 100 parts by mass of deionized water to be continuously stirred for 24 h to prepare a modified nanoparticle suspension;
[0092] the superhydrophobic nano paint prepared in the step (1) was subjected to spray drying for 1-2 h under conditions of an inlet temperature of 160-220° C., a spraying air pressure of 0.3 Mpa and a moisture evaporation capacity of 1-200 L/h to remove deionized water so as to obtain a superhydrophobic nanoparticle powder;
[0093] 4 parts by mass of porous ceramic particles prepared by high temperature sintering and 0.2 part by mass of Evonik DynasylanHydrosil 1151 amino waterborne siloxane were added into 60 parts by mass of deionized water to be stirred for 12 h and then the modified nano powder prepared in the step (2) was added into the mixture to be continuously stirred for 12 h to prepare an impregnated porous powder with superhydrophobic particles suspension, and then the suspension was subjected to spray drying for 1-2 h under conditions of an inlet temperature of 160-220° C., a spraying air pressure of 0.3 Mpa and a moisture evaporation capacity of 1-200 L/h to obtain a final porous powder;
[0094] 5 parts by mass of the impregnated porous powder with superhydrophobic particles was mechanically stirred and dispersed in 30 parts by mass of propylene glycol methyl ether, then 10 parts by mass of fluorocarbon resin, 4 parts by mass of an aliphatic polyisocyanate curing agent, 0.25 part by mass of polyacrylate as a dispersant, 0.25 part by mass of amino siloxane and 0.2 part by mass of propylene glycol methyl ether acetate as a stabilizer were added, and the mixture was stirred for 10 min to obtain superhydrophobic paint applying the porous powder, and if the fluorocarbon resin and the aliphatic polyisocyanate curing agent were equivalently replaced by epoxy resin and an aliphatic amine curing agent or ceramic paint and the aliphatic polyisocyanate curing agent, paint under different adhesives could be obtained; and
[0095] the paint applying the powder prepared in the step (4) was coated to a cleaned surface of any substrate, and the substrate was placed in a 160° C. oven to be heated and dried for 2 h to obtain the superhydrophobic coating.
[0096] Brick red slurry in FIG. 1c shows a macroscopic morphology of the impregnated porous powder with superhydrophobic particles suspension, after the power subjected to spray drying is dried at a high temperature, a water drop dyed by methyl blue is spherical on the surface thereof, and compared with an original powder, excellent superhydrophobicity obtained after modification is shown; and FIG. 3a-c shows a macroscopic photo and wettability of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles, wherein the contact angle of the water drop on the surface of the coating is 163.6°, and the rolling angle thereof is 1.6°. FIG. 4a-d shows morphologies of the original high temperature sintered porous ceramic particles and the prepared superhydrophobic nanoparticle impregnating porous powder in the coating, and it can be seen that nano silicon dioxide is stored in holes of porous ceramic particles and the superhydrophobic nanoparticle impregnating porous powder and the adhesive together form a compact structure in the coating.
Example 3
[0097] FIG. 5a-b is SEM diagrams of mechanical wear resistance of the superhydrophobic coating prepared by the impregnated porous powder with superhydrophobic particles and a surface subjected to severe mechanical wear in the example 2. Benefited from good dispersibility of the impregnated porous powder with superhydrophobic particles itself and the strong bonding force of the adhesive as well as an armor protection effect of the preferred high strength high temperature sintered porous ceramic particles through a test and release of the superhydrophobic nanoparticles under a condition of severe mechanical damage, the superhydrophobic coating still can keep excellent superhydrophobicity after 2000 r of Taber abrasion (1 Kg load).
Example 4
[0098] In the embodiment, inorganic nanoparticles are silicon dioxide, a volatile organic solvent is butyl acetate, a waterborne hydrophobic treatment agent is waterborne perfluorodecyl siloxane, and porous microparticles are diatomite. The preparation method includes the following preparation steps:
[0099] 8 parts by mass of a chained nano silicon sol, 2 parts by mass of a spherical nano silicon sol, 6 parts by mass of ammonia water and 2 parts by mass of perfluoroalkyl siloxane were dispersed in 100 parts by mass of deionized water to be continuously stirred for 24 h to prepare a modified nanoparticle suspension;
[0100] the superhydrophobic nano paint prepared in the step (1) was subjected to spray drying for 1-2 h under conditions of an inlet temperature of 160-220° C., a spraying air pressure of 0.3 Mpa and a moisture evaporation capacity of 1-200 L/h to remove deionized water so as to obtain a superhydrophobic nanoparticle powder;
[0101] 16 parts by mass of diatomite, 3 parts by mass of ammonia water, 0.2 part by mass of waterborne perfluorodecyl siloxane, 0.1 part by mass of Evonik DynasylanHydrosil 1151 amino waterborne siloxane were added into 60 parts by mass of deionized water to be stirred for 12 h and then the modified nano powder prepared in the step (2) was added into the mixture to be continuously stirred for 12 h to prepare a impregnated porous powder with superhydrophobic particles suspension, and then the suspension was subjected to spray drying for 1-2 h under conditions of an inlet temperature of 160-220° C., a spraying air pressure of 0.3 Mpa and a moisture evaporation capacity of 1-200 L/h to obtain a final porous powder;
[0102] 6 parts by mass of the impregnated porous powder with superhydrophobic particles was mechanically stirred and dispersed in 24 parts by mass of butyl acetate, then 8 parts by mass of fluorocarbon resin, 3.2 parts by mass of an aliphatic polyisocyanate curing agent, 0.2 part by mass of polyacrylate as a dispersant, 0.2 part by mass of amino siloxane and 0.15 part by mass of propylene glycol methyl ether acetate as a stabilizer were added, and the mixture was stirred for 10 min to obtain superhydrophobic paint applying the porous powder, and if the fluorocarbon resin and the aliphatic polyisocyanate curing agent were equivalently replaced by epoxy resin and an aliphatic amine curing agent or ceramic paint and the aliphatic polyisocyanate curing agent, paint under different adhesives could be obtained; and
[0103] the paint applying the powder prepared in the step (4) was coated to a cleaned surface of any substrate, and the substrate was placed in a 180° C. oven to be heated and dried for 2 h to obtain the superhydrophobic coating.
[0104] FIG. 1a shows the impregnated porous powder with superhydrophobic particles suspension, and the powder subjected to spray drying is hydrophilic and can be dispersed in various solvents; and it is superhydrophobic after high temperature drying, and can still be dispersed in the organic solvent to form even paint effectively.
Example 5
[0105] FIG. 6a-b shows surface and section structural diagrams of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles in the example 4, and it can be seen from the figure that the superhydrophobic nanoparticles can be successfully stored to pores of porous diatomite. FIG. 7a-c is morphologic diagrams of the porous diatomite particles after and before impregnating and variations of pore diameters of diatomite under conditions of different impregnating capacities. If there are few nanoparticles, the excellent effect achieved by the porous powder impregnating the particles is not prominent, and if there are excessive nanoparticles, they cannot be stored, so that the bonding force between the particles and the adhesive will be reduced, resulting in decline of durability of the coating; the maximum impregnating capacity of used diatomite is 30% through nano silicon sols (chained and spherical nanoparticles are matched) in different shapes via multiple tests, and therefore, the impregnating capacity is controlled precisely.
Example 6
[0106] FIG. 8a-b is an SEM morphologic diagram of nano silicon dioxide stored in the diatomite particles and scratched under different microscopic pressures in the example 1, reflecting the microscopic mechanical performance of the coating. When the load is 10 mN, illustration of the SEM image after scratching shows intact nano silicon dioxide stored in holes of diatomite. There is only a little scratch observed on diatomite, showing that diatomite has enough mechanical strength and a capacity of resisting wear. Diatomite provides nano silicon dioxide with armor protection. When the load is increased to 100 mN, diatomite particles are damaged, and the embedded nano silicon dioxide escapes from hoes and is observed on the surface of the coating, showing that the loss of particle is compensated by self-adaptive release, the damaged area is repaired in real time, and the coating is maintained superhydrophobic.
Example 7
[0107] The research group has provided a highly wear-resistant normal temperature cured superhydrophobic coating by integrating superhydrophobic particles and primer and a preparation method previously (a compare document CN110003735 A). In comparison, 4 parts of the final impregnated porous powder with superhydrophobic particles in the example 4 was added into 25 parts by mass of an acetone solution according to a test condition of the example 2 of the compare document CN110003735 A, 0.1 part by mass of an acrylate copolymer was added, the mixture was ultrasonically dispersed for 15 min, then 10 parts by mass of a fluorocarbon resin was added into the mixture to be mechanically stirred for 10 min, 0.5 part by mass of chloridized modified polypropylene, 0.6 part by mass of propylene glycol methyl ether acetate, 0.2 part by mass of hydrogenated castor oil and 0.3 part by mass of dibutyltin dilaurate were added to be stirred for 10 min, and then 2.5 parts by mass of the same fluorocarbon resin curing agent was added to be mechanically and evenly stirred to obtain final paint, and the paint was sprayed to a surface of a glass sample to obtain a final superhydrophobic coating. FIG. 9a shows wear resistance of the coating prepared in the example 2 of the compare document CN110003735 A, and FIG. 9b shows wear resistance of the final coating prepared by the impregnated porous powder with superhydrophobic particles in the example 4 of the present invention. It can be seen that under the same test conditions, the wear resistance is improved by nearly 5 times, and the superhydrophobic coating prepared by the impregnated porous powder with superhydrophobic particles is more excellent in stability performance, and is compact without dusting. The coatings can be maintained superhydrophobic after being subjected to 1 kg load Taber abrasion, RCA tape abrasion, sand ablation, high-pressure water jet impact, high speed sandy water ablation and salt solution immersion. Durability is improved by over 10 times compared with the superhydrophobic coatings, such as commercial Ultra-ever dry coating and Neverwet coating, prepared in the prior art, and the coating can stand against various severe environments.
Example 8
[0108] FIG. 10a-c shows universality of the intelligent long-acting superhydrophobic paint prepared by applying the impregnated porous powder with superhydrophobic particles in the example 4. The method can be suitable for various organic resins and inorganic adhesives that are either low surface energy adhesives or non-hydrophobic waterborne adhesives, thereby improving the durability of the superhydrophobic coating remarkably. Through reported superhydrophobic coating technologies, a certain adhesive or a specific adhesive is often preferred to improve the durability of the coating. The limitation is solved effectively due to universality of the present invention.
Example 9
[0109] FIG. 11a-b shows an FTIR (Fourier Transform Infrared Spectrometer) of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles, the impregnated porous powder with superhydrophobic particles and the fluorocarbon resin in the example 4 as well as fluorine contents and hydroxyl contents of a superhydrophobic nanopowder obtained in the step (1) of the example 4, a microporous powder with a low modification degree obtained in the step (3) of the example 4 by direct spray drying without adding the nanopowder obtained in the step (1) and the final impregnated porous powder with superhydrophobic particles obtained in the example 4. After the fluorocarbon resin coatings the impregnated porous powder with superhydrophobic particles, —OH and —N═C═O peaks disappear and —N—C peaks are enhanced, showing that the resin and the impregnated porous powder with superhydrophobic particles are bonded successfully. It can be seen via a fluorine grafting amount and a hydroxyl residual amount that residual hydroxyl of silicon dioxide is 10 times lower than that of the micro porous powder with the low degree of modification, so that it is superhydrophobic after high temperature drying. The micro porous powder with the low degree of modification provides hydroxyl capable of being tightly bonded with the resin and the substrate. A pulverizing process or a pulping process is controlled, so that the prepared powder or slurry retains part of active groups, so that it is hydrophilic, and therefore, it is convenient to improve the dispersibility in the film forming matter. By regulating and controlling the degree of modification precisely, the fluorine contents and hydroxyl contents of the final impregnated porous powder with superhydrophobic particles are in optimal ranges. FIG. 12 shows mechanical performance of the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles. Compared with used adhesive and common superhydrophobic coating, the superhydrophobic of the superhydrophobic coating is improved by 55-100%, and the ductility is improved by about 66.7% compared with that of the common superhydrophobic coating. After it is stretched to yield strength, the adhesive is still adhered to the surface of the porous powder in a drawing state, thereby providing a beneficial effect to improving the tensile strength. Besides, the compressive mechanical property of the superhydrophobic coating is also remarkably improved compared with that of the common superhydrophobic coating, including hardness, Young modulus and the like. FIG. 13 shows an adhesive strength of the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles. The tangential adhesive strength and the normal adhesive strength of the superhydrophobic coating are improved by 50% or above compared with those of the adhesive and the common superhydrophobic coating. A grid adhesive strength test is performed according to an ISO 2409 standard, the adhesive strength of a used tape on the coating is not lower than (10+−) N/25 mm, and it can be found that the coating does not fall off, is adhered 100% and reaches the grade 0 in the standard.
Example 10
[0110] In the embodiment, inorganic nanoparticles are titanium dioxide, a volatile organic solvent is acetone, a hydrophobic modifier is propyl trimethoxysilane and Evonik Protectosil WS 670, and porous microparticles are porous silicon dioxide. The preparation method includes the following preparation steps:
[0111] 10 parts by mass of a titanium dioxide sol, 6 parts by mass of ammonia water, 0.3 part by mass of propyl trimethoxysilane and 0.8 part by mass of Evonik Protectosil WS 670 were dispersed in 100 parts by mass of deionized water to be continuously stirred for 24 h to prepare a modified nanoparticle suspension;
[0112] a supernate was filtered when the superhydrophobic nano paint prepared in the step (1) centrifugalized by a 6000 r centrifugal machine to remove deionized water, and the coating was dried for 1 h in a vacuum drying box to obtain a superhydrophobic modified nanoparticle powder;
[0113] 8 parts by mass of porous silicon dioxide, 0.3 part by mass of Evonik DynasylanHydrosil 1151 amino waterborne siloxane were added into 80 parts by mass of deionized water to be stirred for 12 h and then the modified nanoparticle powder prepared in the step (2) was added into the mixture to be continuously stirred for 12 h to prepare a superhydrophobic particle impregnating porous particle suspension, and then the suspension was subjected to spray drying for 1-2 h under conditions of an inlet temperature of 160-220° C., a spraying air pressure of 0.3 Mpa and a moisture evaporation capacity of 1-200 L/h to obtain a final porous powder;
[0114] 6 parts by mass of the impregnated porous powder with superhydrophobic particles was mechanically stirred and dispersed in 30 parts by mass of acetone, then 12 parts by mass of epoxy resin, 2 parts by mass of a closed polyisocyanate curing agent, 0.5 parts by mass of polyacrylate as a dispersant, 0.4 part by mass of amino siloxane and 0.3 part by mass of propylene glycol methyl ether acetate as a stabilizer were added, and the mixture was stirred for 15 min to obtain superhydrophobic paint applying the porous powder; and
[0115] the paint applying the impregnated porous powder with superhydrophobic particles prepared in the step (4) was coated to a cleaned surface of any substrate, and the substrate was placed in a 220° C. oven to be heated and dried for 2 h to obtain the superhydrophobic coating.
[0116] FIG. 13a shows the impregnated porous powder with superhydrophobic particles suspension, and the powder subjected to spray drying is hydrophilic and can be fully dispersed in various solvents to form even paint.
Example 11
[0117] FIG. 14a-b shows a scale prevention property of the intelligent long-acting superhydrophobic paint prepared by applying the impregnated porous powder with superhydrophobic particles in the example 10. The used cement slurry is spherical on the surface of the coating and cannot be unfolded, showing the scale prevention property of the coating. When the coating is inclined, the solidified cement slurry falls off naturally under the action of gravity, and the surface of the coating is still kept in an initial state.
Example 12
[0118] FIG. 15a-b shows an anti-condensation property of the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles in the example 10. When condensate dewdrops are solidified, they are spherical, few and low in coverage. Along with growth of the condensate dewdrops, under the action of gravity, the condensate dewdrops easily roll away from the surface of the coating and take away the condensate dewdrops on the way, so that the coverage of the condensate dewdrops is greatly reduced. As time goes on, the exposed dried area will be subjected to continuous condensation and self-removal to achieve a dynamic balance, so that the coverage of the condensate dewdrops on the surface of the coating is maintained at a low level all the time.
Example 13
[0119] FIG. 16a-d shows a frosting prevention property of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles in the example 10. The initial growth speed of a frost layer is low. The surface of the coating has the obvious frost layer till it is condensed for 20 min, and the frosting behavior is inhibited obviously. When frost is melted, the whole frost layer rolls up and falls off, and the defrosting speed is high; and after defrosting, the surface is dry and is free of any residues. An excellent frosting prevention property is shown.
Example 14
[0120] FIG. 17a-d shows a dropwise condensation property of hot water vapor of the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles in the example 10. When hot water vapor liquid drops are solidified, they are spherical, low in forming speed and low in coverage. Along with growth of the condensed liquid drops, under the action of gravity, the liquid drops easily roll away from the surface of the coating and take away the liquid drops on the way. As time goes on, the liquid drops will be condensed continuously and roll away to achieve a dynamic balance, so that the coverage of the liquid drops on the surface of the coating is maintained at a low level all the time. A lot of liquid drops will be condensed on the surface of the coating at the beginning after a load is applied to wear, but the hot water vapor liquid drops are still spherical when being condensed. As time goes, they will achieve a dynamic balance state again, so that the surface of the coating maintains low liquid drop coverage.
Example 15
[0121] FIG. 18a-b shows a salt-spray corrosion effect of the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles in the example 4. i-iv are the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles prepared by different adhesives, v and vi are fluorocarbon resin and epoxy resin coatings, and vii-ix are comparative superhydrophobic coatings, and vii-ix are comparative superhydrophobic coatings; the surface of the superhydrophobic coating applying the impregnated porous powder with superhydrophobic particles still has no rust in 1000 h, and shows excellent salt spray corrosion resistance in various adhesives. When the time is 5000 h, the roll-off angle of the coating is still smaller than 20°, and the surface of the sample is free of rust.
Example 16
[0122] FIG. 19a-c shows a salt solution immersion resisting effect of the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles in the example 4. compared with anti-corrosive coatings in the market (for example, epoxy resin and fluorocarbon resin coatings) and common superhydrophobic coatings such as Ultra-ever dry and Neverwet coatings, the low frequency modulus of impedance of the superhydrophobic coating is improved by several orders of magnitudes, and the anti-corrosive time thereof is also prolonged by more than 10 times; besides, the open circuit potential of the superhydrophobic coating is kept stable all the time as the salt solution immersion time is prolonged, and the open circuit potentials of other coatings are reduced remarkably.
Example 17
[0123] FIG. 20a-b is macroscopic morphologic diagrams of an anti-corrosive hydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles prepared by a wet spraying process after and before anti-salt-spray corrosion, with fluorocarbon resin and the curing agent thereof are equivalently replaced by epoxy resin and the curing agent, by using the paint in the example 4. A compact structure is formed on the surface of the coating by epoxy resin to protect a substrate, and the impregnated porous powder with superhydrophobic particles is evenly dispersed in the coating to block permeation of external salt spray. Compared with the corrosion resistance of the pure epoxy resin coating, the corrosion resistance of the coating is improved by nearly 100 times. The surface of the sample is still free of rust in 5000 h of salt spray.
Example 18
[0124] FIG. 21a-f shows a defrosting property of the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles in the example 10. Compared with conventional commercially used hydrophilic coating heat exchangers, the defrosting process of a superhydrophobic coating heat exchanger prepared by applying the impregnated porous powder with superhydrophobic particles is more rapid in process with frost layers falling in block and is free of water drop residues; the defrosting energy consumption of the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles is lower compared with that of the nano superhydrophobic coating and the commercial hydrophilic coating, and under different working conditions such as condensation, dust contamination, frost formation and defrosting, the efficiencies are higher; in a dust blowing test, damage conditions caused by pollution and sand dust under actual working conditions are simulated. Compared with the nano superhydrophobic coating heat exchanger, the frosting heat exchange amount of the heat exchanger with the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles is higher and the defrosting energy consumption thereof is lower. The efficiency attenuation ratio of the heat exchanger after dust blowing is lower, showing breakthrough innovation and long action of the superhydrophobic coating prepared by applying the impregnated porous powder with superhydrophobic particles.
[0125] The above examples are merely the preferred embodiments of the present invention. It shall be pointed out that those of ordinary skill in the technical field can made several improvements without departing the principle of the present invention, and these improvements shall be made within the protection range of the present invention.
