CN103288364A - Preparation method of super-hydrophobic surface of glass - Google Patents

Abstract

The invention relates to the field of superhydrophobic surfaces. In order to overcome the problems of poor adhesion between the current superhydrophobic _SiO2 micronano double rough structure layer and the glass substrate, and insufficient hydrophobicity, the invention proposes a method for preparing a glass superhydrophobic surface. The fluorine-silicon modified acrylate emulsion was prepared first, then the modified SiO ₂ sol was prepared, and finally the glass superhydrophobic surface was prepared. The preparation method of the superhydrophobic surface is simple and low in cost. The hydrophobic coating not only has excellent hydrophobicity, but also has excellent bonding force between the coating and glass, which can ensure that the coating maintains its superhydrophobicity for a long time.

Description

A kind of preparation method of glass superhydrophobic surface

technical field

The invention relates to the field of superhydrophobic surfaces, in particular to a preparation method and application of a glass superhydrophobic surface.

Background technique

Surface wettability is one of the important properties of solid surfaces. When the contact angle between solid surface and water is greater than 150°, the surface is superhydrophobic. Professors W.Barthlott and C.Neinhuis of the University of Bonn in Germany, through the observation of the microstructure of the surface of plant leaves, believe that the existence of micron-sized papillae and surface wax on the rough surface makes it super-hydrophobic. On the basis of this research, Academician Jiang Lei and others found that there are nanostructures on the microstructured papillae on the surface of the lotus leaf, revealing the cause of the lotus leaf effect. These findings provide a development direction for the preparation and research of superhydrophobic surfaces. Due to its unique surface properties, it has important research significance in daily life and industrial fields. If a super-hydrophobic surface is made on the glass surface, the super-hydrophobic surface can be used to prevent dust pollution, and it can also inhibit microorganisms from adhering to the glass surface, so it can be used as a self-cleaning material for the glass surface. The popularization of automobiles and the increase of high-rise buildings make glass with self-cleaning function attract extensive attention. The preparation of superhydrophobic surfaces on glass surfaces has become a research hotspot.

There are two main ways to prepare superhydrophobic surfaces: one is to construct micro-nano double rough structures on the surface of hydrophobic materials; the other is to obtain rough surface structures first, and then modify low surface energy substances on the rough surfaces. Low surface energy materials are the material basis for obtaining superhydrophobic surfaces. Commonly used low surface energy materials include fluorocarbon resins, fluorosilicone resins, and silicone resins. The most important silicone resin is a thermosetting polysiloxane system with a highly cross-linked structure. Due to the high bond energy of the Si-O bond, the large bond angle, the soft Si-O-Si main chain, and the side chain group Acting as a shield, the specificity of these chain structures endows silicone polymers with many excellent properties. SiO ₂ is the simplest unit of the siloxane segment in the silicone resin, and has the characteristics of simple preparation process and low production cost.

At present, the methods for preparing superhydrophobic surfaces mainly include phase separation method, template method, sol-gel method, etching method, photochemical method, chemical vapor deposition method and so on. The sol-gel method is the most common method for preparing superhydrophobic surfaces. This method can better control the surface structure, effectively adjust and improve the surface roughness, and endow the coating with superhydrophobicity. The sol-gel method has mild reaction conditions, and normal temperature and pressure are enough, so it is widely used. However, when the superhydrophobic _SiO2 prepared by the sol-gel method is applied, it has poor adhesion to the glass substrate, poor abrasion resistance, and is easily abraded during use, resulting in a decrease in hydrophobicity. Therefore, the application of superhydrophobic surfaces on glass has always been There is no industrialization.

Chinese patent CN20120110100 discloses a method for preparing a glass superhydrophobic surface. This method deposits a layer of rough and porous _SiO2 film by electrodeposition technology, and then modifies the deposition surface with a long-chain alkyl siloxane hydrolyzate. In order to improve the hydrophobicity of the _SiO2 film, the porous _SiO2 film was immersed in the long-chain alkylsiloxane hydrolyzate, so that the long-chain hydrophobic groups were deposited on the surface of the film. However, between the SiO ₂ film itself and the substrate, SiO ₂ with a micronano double-rough structure is connected to the substrate, resulting in poor adhesion and friction resistance, and it is easy to wear during use, resulting in a decrease in hydrophobicity, thus resulting in a long service life of the hydrophobic surface. Short, repeated dipping is required to achieve superhydrophobicity again.

Contents of the invention

In order to overcome the current superhydrophobic SiO ₂ micro-nanometer double rough structure layer and the problems of poor adhesion to the glass substrate and insufficient hydrophobicity, the present invention proposes a method for preparing a superhydrophobic surface of glass. The preparation method of the superhydrophobic surface is simple, The cost is low, and the hydrophobic coating not only has excellent hydrophobicity, but also has an excellent bonding force between the coating and the glass, which can ensure that the coating maintains its superhydrophobicity for a long time.

The present invention is achieved through the following technical solutions: A method for preparing a glass superhydrophobic surface, the method for preparing a glass superhydrophobic surface is the following steps:

(1) Preparation of fluorosilicone modified acrylate emulsion,

(2) Preparation of modified SiO ₂ sol,

(3) Preparation of glass superhydrophobic surface.

1. Fluorosilicone modified acrylate emulsion in step (1) is prepared from the following components, and the specific preparation steps are as follows:

(a) The parts by weight of the components of the fluorosilicon-modified acrylate emulsion are:

(b) Weigh the above-mentioned components according to the number of components, mix alkyl methacrylate and alkyl acrylate to make monomer I, hydroxyalkyl acrylate or hydroxyalkyl methacrylate, organic Siloxane, fluorine-containing alkyl acrylate or fluorine-containing alkyl methacrylate are mixed to form monomer II. Preferably, the mass ratio of monomer I to monomer II is 2~4:1;

(c) Add 55%~75% of water, 50%~80% of emulsifier, 60%~85% of initiator and pH regulator into the reaction kettle, stir for 10~20 minutes and then heat up to 75 ~80 ℃, take 10%~20% of the monomer I and add it to the reaction kettle for 15~30 minutes, after the dropwise addition is completed, keep it warm for 15~30 minutes, and then add 50%~70% of the monomer I at 2.5 Add dropwise to the reaction kettle within ~4 hours, after the dropwise addition, keep warm for 15~30 minutes to obtain the emulsion;

(d) Dissolve the remaining emulsifier and initiator in the remaining water to make a mixed solution, add the monomer II to the monomer I dropwise and keep stirring while mixing the mixture of the above monomer I and monomer II and the remaining The mixed solution made of water, emulsifier and initiator is continuously added dropwise to the emulsion obtained in step (c) within 0.5~1.5 hours; after the dropwise addition, react for 0.5~1 hour, and then heat up to 80~85°C Keep it warm for 1-2 hours, then lower the temperature to 40-50°C, filter and discharge the material to obtain a fluorosilicon-modified acrylate polymer emulsion. During the reaction process, measure the pH value of the reaction system every 20 to 40 minutes, and adjust the pH value between 6.0 and 7.0. In this step, use the same substance as the pH regulator to adjust the pH value of the reaction system.

Steps (c), (d) limit the adding time of materials in order to maintain the heat balance in the reactor and a certain reaction rate of the reaction materials. Different weights of materials can maintain the reaction speed of materials in reactors of corresponding sizes.

In each component of described fluorosilicon modified acrylate emulsion:

Described alkyl methacrylate is selected from methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, pentyl methacrylate, hexyl methacrylate, methacrylic acid One or several mixtures in any proportion of isooctyl esters;

The alkyl acrylate is selected from methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, hexyl acrylate, isooctyl acrylate or a mixture of several in any proportion;

The organosiloxane is selected from vinyltrimethoxysilane, vinyltriethoxysilane, vinyltributoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methoxysilane Acryloyloxypropyltriethoxysilane or a mixture of several in any proportion;

The hydroxyalkyl acrylate or hydroxyalkyl methacrylate is selected from 2-hydroxyethyl acrylate, 3-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 5-hydroxypentyl acrylate, A mixture of one or more of 6-hydroxyhexyl acrylate, 2-hydroxyethyl methacrylate, and 3-hydroxypropyl methacrylate in any proportion;

The fluorine-containing alkyl acrylate or fluorine-containing alkyl methacrylate is selected from hexafluorobutyl acrylate, hexafluorobutyl methacrylate, trifluoroethyl acrylate, trifluoroethyl methacrylate, Difluoroheptyl, dodecafluoroheptyl methacrylate, tridecafluorooctylethyl acrylate, tridecafluorooctylethyl methacrylate, hexafluorobutyl acrylate, hexafluorobutyl methacrylate, decafluorooctyl acrylate One of trifluorooctyl, trifluorooctyl methacrylate, dodecafluoroheptyl acrylate, and dodecafluoroheptyl methacrylate;

The initiator is selected from persulfate systems, preferably, selected from one or more mixtures in arbitrary proportions among potassium persulfate, sodium persulfate, and ammonium persulfate;

The emulsifier is a compound of anionic emulsifier and reactive emulsifier, and the reactive emulsifier is 1 to 4 times the mass of the anionic emulsifier, wherein the anionic emulsifier is selected from disodium dodecyl diphenyl ether sulfonate ( DSB), sodium dodecylbenzenesulfonate (LAS), sodium dodecyl sulfate (SDS) or a mixture of several in any proportion; the reactive emulsifier is selected from 2-acrylamido-2-methanol Ammonium-propylsulfonate (AMPS-Na), 2-acrylamido-2-methyl-propylammoniumsulfonate (AMPS-NH ₄ ), 1-allyloxy-2-hydroxypropyl Sodium sulfonate (HAPS), 2-acrylamidotetradecanesulfonic acid sodium salt (NaAMC14S), sodium methacrylate hydroxypropyl sulfonate (HPMAS) or a mixture of several in any proportion;

The pH regulator is selected from sodium bicarbonate, potassium bicarbonate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, or a mixture of several in any proportion;

Described water is deionized water.

The invention prepares the fluorine silicon modified acrylate emulsion through the principle of particle design. The low surface energy organosilicon monomer and fluorine-containing alkyl acrylate or fluorine-containing alkyl methacrylate monomer are designed in the particle shell, and the content and distribution of fluorine and silicon range from about 50-70% of the particle radius to The gradual increase of the surface can give full play to the hydrophobic effect of the fluorine-silicon chain segment. A small amount of silicone, fluorine-containing alkyl acrylate or fluorine-containing alkyl methacrylate monomer can achieve a good hydrophobic effect, and the water contact angle can reach Reach 110~120°. On the other hand, by adopting the gradient feeding method, the added organic silicon and fluorine-containing monomers are closely integrated with the latex particles, and no phase separation occurs, so that the surface of the coating film has stable performance.

2. The modified SiO ₂ sol in step (2) is prepared from the following components, and the specific preparation steps are as follows,

(a) The parts by weight of the components of the modified SiO _sol are:

(b) Weigh the above-mentioned components according to the number of each component, add the alkyl orthosilicate dropwise into the mixed solution composed of water, alkaline catalyst and alcohol, and hydrolyze it at 50-70°C for 1-6 hours to prepare into hydrolyzate A;

(c) Add methyltrialkoxysilane dropwise to the above-mentioned hydrolyzate A, continue to hydrolyze for 1~6h, and make hydrolyzate B;

(d) Add long-chain alkyltrialkoxysilane or long-chain fluorine-containing alkyltrialkoxysilane into hydrolyzate B, then hydrolyze for 1~6h, keep warm for 12~24h, then cool down to room temperature to obtain modified SiO ₂ sol.

During the preparation of the modified SiO ₂ sol, the whole process system kept stirring.

Described modified _SiO In each component of sol:

The alkyl orthosilicate is selected from one of methyl orthosilicate, ethyl orthosilicate, and butyl orthosilicate;

The alcohol is selected from one of methanol, ethanol, butanol, preferably, the alcohol is the same alcohol as the alkyl part in the alkyl orthosilicate;

Described methyltrialkoxysilane is selected from the one in methyltrimethoxysilane, methyltriethoxysilane, methyltributoxysilane, as preferably, described methyltrialkoxysilane The alkyl silane is the same as the alkyl part in the alcohol;

The long-chain alkyltrialkoxysilane or long-chain fluorine-containing alkyltrialkoxysilane is selected from octyltrimethoxysilane, dodecyltrimethoxysilane, tridecafluorooctyltrimethoxy Silane, Hexadecyltrimethoxysilane, Octadecyltrimethoxysilane, Perfluorooctyltrimethoxysilane, Heptadecylfluorodecyltrimethoxysilane, Octyltriethoxysilane, Dodecane Triethoxysilane, Tridecafluorooctyltriethoxysilane, Hexadecyltriethoxysilane, Octadecyltriethoxysilane, Perfluorooctyltriethoxysilane, Seventeen One or more of fluorodecyltriethoxysilane;

Described basic catalyst is selected from the one in ammoniacal liquor, tetramethylammonium hydroxide, tetraethylammonium hydroxide;

Described water is deionized water.

The room temperature of the preparation method usually refers to 25°C and the pressure is 101 kPa.

Fluorosilicone modified acrylate emulsion of the present invention is to improve the cohesive force between the glass substrate, and provides a kind of by forming SiO ₂ micro-nanometer double rough structure, introducing long-chain alkyl or long-chain fluorine-containing alkyl to improve its hydrophobic approach. The fluorine-silicon content and the distribution of functional groups in the fluorine-silicon modified acrylate emulsion gradually increase from 50% to 70% of the particle radius to the surface, and are mainly distributed in the shell layer to give full play to the role of the fluorine-silicon low surface energy segment. The contact angle can reach 110~120°. When glass is coated with fluorosilicon-modified acrylate emulsion and modified SiO ₂ sol is used, the micro-nanometer double rough structure formed by SiO ₂ sol itself and the grafted on the surface of the glass coating film The long-chain alkyl or long-chain fluorine-containing alkyl work together to further improve its surface hydrophobicity. The present invention adopts long-chain alkyl siloxane or long-chain fluorine-containing alkyl siloxane to modify SiO ₂ , and grafts methyl group and long-chain alkyl or long-chain fluorine-containing alkane on SiO ₂ particles by sol-gel method. After the micro-nano double rough structure is formed on the _SiO2 particles, due to the low surface energy of the long-chain alkyl or long-chain fluorine-containing alkyl, the hydrophobicity of the coating surface can be further improved, and the water contact angle can reach more than 155°.

3. The superhydrophobic surface of glass in step (3) is prepared by spin coating method or dipping and pulling method commonly used in liquid film formation.

The steps of the spin-coating method are as follows: spin-coat the fluorosilicon-modified acrylate emulsion on the glass sheet in a spin-coater for 2-10 minutes, take it out, cure it at room temperature for 1-3 hours, and then spin-coat the cured glass sheet with modified SiO2 in a spin-coater. ₂ Sol 2~5min, repeat spin coating 3~5 times after the surface is dry, and finally place it in an oven at 100~120℃ for 1~2h.

The steps of the dipping and pulling method are: immerse the glass sheet in the fluorosilicon modified acrylate emulsion for 2-10 minutes, take it out, cure at room temperature for 1-3 hours, then immerse the glass sheet in the modified SiO ₂ sol for 2-10 minutes, repeat Pull it 3~5 times, and place it in an oven at 100~120℃ for 1~2h.

The invention provides a method for preparing a superhydrophobic surface of glass, through the preparation of fluorine-silicon modified acrylate emulsion to enhance the adhesion between the coating film and the glass substrate and the long-chain alkyl siloxane or long-chain fluorine-containing alkyl siloxane Modified superhydrophobic SiO ₂ sol improves hydrophobicity. Fluorosilicone-modified acrylate emulsion introduces organosiloxane and fluorine-containing monomers, and the distribution of fluorosilicone hydrophobic groups and functional groups in the colloidal particles of the polymer emulsion gradually increases from 50% to 70% of the colloidal particle radius to the surface. The content of fluorine-silicon chain segments and other monomer components gradually increases, eliminating the difference in particle composition and structure. On the other hand, when the emulsion particles are cured, the fluorine-silicon hydrophobic segments are mainly concentrated in the outer layer of the particles, and are easy to migrate to the surface of the coating film, which can give full play to the role of the fluorine-silicon hydrophobic groups and improve the cost performance of the product. The modified SiO ₂ sol grafts long-chain alkyl groups or long-chain fluorine-containing alkyl groups on SiO ₂ particles through the sol-gel method to form a micro-nano double-rough structure. The introduction of long-chain fluorine-containing alkyl siloxane makes the surface of this rough structure have lower surface energy, and the hydrophobicity is further enhanced. When preparing the superhydrophobic surface, the acrylate emulsion modified by fluorine silicon is used as the film-forming material, and the hydrophobic _SiO sol modified by long-chain fluorine-containing alkyl siloxane is used to form a micro-nano structure on the surface of the coating film. The low surface energy of fluorine-silicon and the micro-nano double rough structure of _SiO2 work together to endow the coating with excellent superhydrophobicity.

Compared with prior art, the beneficial effect of the present invention is:

(1) The present invention prepares fluorosilicon-modified acrylate emulsion through the principle of particle design. Low surface energy organosilicon monomers and fluorine-containing alkyl acrylate or fluorine-containing alkyl methacrylate monomers are designed in the particle shell, and the content and distribution of fluorine and silicon range from about 50-70% of the particle radius to The gradual increase of the surface can give full play to the hydrophobic effect of the fluorine-silicon chain segment. A small amount of silicone, fluorine-containing alkyl acrylate or fluorine-containing alkyl methacrylate monomer can achieve a good hydrophobic effect, and the water contact angle can reach Reach 110~120°. On the other hand, by adopting the gradient feeding method, the added organic silicon and fluorine-containing monomers are closely integrated with the latex particles, and no phase separation occurs, so that the surface of the coating film has stable performance.

(2) The present invention uses long-chain alkyl siloxane or long-chain fluorine-containing alkyl siloxane to modify _SiO2 , and grafts methyl groups and long-chain alkyl groups or long-chain alkyl groups on _SiO2 particles by sol-gel method. Fluorine-containing alkyl groups, after forming a micro-nano double rough structure on _SiO2 particles, due to the low surface energy of long-chain alkyl groups or long-chain fluorine-containing alkyl groups, the hydrophobicity of the coating surface can be further improved, and the water contact angle can reach 155 ° above.

(3) The preparation method of the superhydrophobic surface of the present invention is simple and low in cost. The hydrophobic coating not only has excellent hydrophobicity, but also has excellent bonding force between the coating and glass, which can ensure that the coating maintains its superhydrophobicity for a long time.

Detailed ways

The present invention will be described in further detail below in conjunction with the examples. The raw materials used in the examples are all commercially available. It should be noted that the examples do not constitute limitations to the protection scope of the present invention.

Example 1:

(1) Preparation of fluorosilicone modified acrylate emulsion;

(a) The components of the fluorosilicon-modified acrylate emulsion are shown in Table 1 below. Mix alkyl methacrylate and alkyl acrylate in the step components to make monomer I, hydroxyalkyl acrylate or hydroxyalkyl methacrylate, organosiloxane, fluorine-containing alkyl acrylate or Alkyl fluoromethacrylate is mixed to make monomer II;

(b) Add 55% of water in step (a), 55% of the mass of the mixture of SDS and AMPS-Na, 60% of potassium persulfate and sodium bicarbonate into the reaction kettle, stir for 15 minutes and then heat up to 75°C, take 10% of the monomer I was added to the reactor in 15 minutes, and kept for 15 minutes after the dropwise addition, and then 50% of the monomer I was added dropwise in the reactor within 2.5 hours, and kept for 15 minutes after the dropwise addition, to obtain Lotion;

(c) Dissolve the remaining emulsifier and initiator in the remaining ionic water to make a mixed solution, add the monomer II to the monomer I dropwise and keep stirring, and at the same time mix the mixture of the above monomer I and monomer II and the remaining The mixed solution made of water, emulsifier and initiator is continuously added dropwise to the emulsion obtained in the above steps within 0.5 hours; after the dropwise addition, react for 1 hour and then heat up to 80°C for 1 hour, then cool down to 40°C, the material was filtered to obtain a fluorosilicon-modified acrylate polymer emulsion.

Measure the pH value of the reaction system every 20 minutes during the reaction in step (c), and use sodium bicarbonate to adjust the pH value of the reaction system to 6.5 when the pH value is outside the range of 6.0-7.0.

(2) Preparation of modified SiO ₂ sol;

(a) Add 1 part of tetraethyl orthosilicate dropwise to a mixed solution consisting of 8 parts of deionized water, 6 parts of ammonia water and 40 parts of ethanol, and hydrolyze at 60°C for 2 hours to make hydrolyzate A;

(b) Add 1 part of methyltriethoxysilane dropwise to hydrolyzate A, continue hydrolyzing for 2 hours, and make hydrolyzate B.

(c) Add 1.5 parts of octyltriethoxysilane to the hydrolyzate B, continue the hydrolysis for 2 hours, keep the temperature for 24 hours and then cool down to room temperature. The whole process system is kept stirring to obtain modified SiO ₂ sol.

(3) Preparation of glass superhydrophobic surface

The steps of the spin coating method are as follows: the glass sheet is spin-coated with fluorosilicon modified acrylate emulsion in a spin coater for 5 minutes, then taken out, cured at room temperature for 1 h, and then the cured glass sheet is spin-coated with modified SiO ₂ sol in a spin coater. After 3 min, the surface was dried and then spin-coated three times, and finally placed in an oven at 100 °C for 1 h.

During the preparation of the fluorosilicone-modified acrylate emulsion, the average particle size of the step (b) is about 65nm, and the final average particle size is 105nm, with a narrow particle size distribution. Transmission electron microscopy (TEM) analysis showed that latex particles were uniform in size and spherical in shape. Elemental analysis shows that from 65nm to 105nm, the content of fluorine and silicon in the particles increases gradually. Scanning electron microscopy (SEM) analysis showed that the emulsion had good film-forming properties, and the film was compact without phase separation. The water contact angle of emulsion coating film is 112°. Infrared analysis (FTIR) of the prepared modified SiO ₂ sol showed that the SiO ₂ particles had been grafted with methyl and octyl groups. Atomic force microscope (AFM) analysis and static water contact angle test (WCA) test were carried out on the prepared coating film. The results showed that the surface of the coating film had a micro-nano double-rough structure, and the water contact angle was 156°, which was superhydrophobic.

Example 2:

(1) Preparation of fluorosilicone modified acrylate emulsion;

(a) The components of the fluorosilicon-modified acrylate emulsion are shown in Table 2 below. Mix alkyl methacrylate and alkyl acrylate in the step components to make monomer I, hydroxyalkyl acrylate or hydroxyalkyl methacrylate, organosiloxane, fluorine-containing alkyl acrylate or Alkyl fluoromethacrylate is mixed to make monomer II;

(b) Add 65% of water in step (a), 65% of the mass of LAS and AMPS-NH ₄ mixture, 70% of ammonium persulfate, and potassium bicarbonate into the reaction kettle, stir for 20 minutes and then heat up to 78 ° C, Take 20% of the monomer I and add it to the reactor in 20 minutes. After the dropwise addition, keep it warm for 20 minutes, then add 60% of the monomer I into the reactor dropwise within 3.5 hours, and keep it warm for 20 minutes after the dropwise addition. , to obtain emulsion;

(c) Dissolve the remaining emulsifier and initiator in the remaining water to make a mixed solution, add the monomer II to the monomer I dropwise and keep stirring while mixing the mixture of the above monomer I and monomer II and the remaining The mixed solution made of water, emulsifier and initiator is continuously added dropwise to the emulsion obtained in step (c) within 1.5 hours. After the dropwise addition, react for 1 hour, then raise the temperature to 83°C and keep it for 1.5 hours, then cool down to 45° C., and the material was filtered to obtain a fluorosilicon-modified acrylate polymer emulsion.

Measure the pH value of the reaction system every 30 minutes during the reaction in step (c), and use sodium bicarbonate to adjust the pH value of the reaction system to 6.5 when the pH value is outside the range of 6.0-7.0.

(2) Preparation of superhydrophobic modified SiO ₂ sol;

(a) Add 6 parts of methyl orthosilicate dropwise to a mixed solution consisting of 15 parts of deionized water, 15 parts of tetramethylammonium hydroxide and 70 parts of methanol, and hydrolyze at 70°C for 1 hour to prepare hydrolyzate A;

(b) Add 3 parts of methyltrimethoxysilane dropwise to hydrolyzate A, and then hydrolyze for 2 hours to make hydrolyzate B.

(c) Add 4 parts of dodecyltrimethoxysilane to the hydrolyzate B, then hydrolyze for 3h, keep warm for 18h and cool down to room temperature to obtain a modified SiO ₂ sol, and the system is kept stirring during the whole process.

(3) Preparation of glass superhydrophobic surface

Immerse the glass sheet in the fluorosilicon modified acrylate emulsion for 3 minutes by dipping and pulling method, take it out, cure it at room temperature for 3 hours, then immerse the glass sheet in the modified SiO ₂ sol for 10 minutes, repeat the pulling 5 times, and put it in an oven at 110°C Placed in the middle for 2h, a super-hydrophobic coating film is obtained.

In the preparation process of the fluorosilicon-modified acrylate emulsion, the average particle size of the step (2) is 62nm, and the final average particle size is 110nm, with a narrow particle size distribution. Transmission electron microscopy (TEM) analysis showed that latex particles were uniform in size and spherical in shape. Elemental analysis shows that from 62nm to 110nm, the content of fluorine and silicon in the particles increases gradually. Scanning electron microscopy (SEM) analysis showed that the emulsion had good film-forming properties, and the film was compact without phase separation. The water contact angle of emulsion coating film is 115°

Infrared analysis (FTIR) of the prepared modified SiO ₂ sol showed that the SiO ₂ particles had been grafted with methyl groups and dodecyl groups. Atomic force microscope (AFM) analysis and static water contact angle test (WCA) test were carried out on the prepared coating film. The results showed that the surface of the coating film had a micro-nano double rough structure, and the water contact angle was 159°, which was superhydrophobic.

Example 3:

(1) Preparation of fluorosilicone modified acrylate emulsion;

(a) The components of the fluorosilicon-modified acrylate emulsion are shown in Table 3 below. Mix alkyl methacrylate and alkyl acrylate in the step components to make monomer I, hydroxyalkyl acrylate or hydroxyalkyl methacrylate, organosiloxane, fluorine-containing alkyl acrylate or Alkyl fluoromethacrylate is mixed to make monomer II;

(b) Add 55% of water in step (a), 75% of the mass of the mixture of DSB and HPMAS, 75% of sodium persulfate, and potassium dihydrogen phosphate into the reaction kettle, stir for 15 minutes and then heat up to 80 ° C, take a single 15% of monomer I was added to the reactor in 30 minutes, and after the dropwise addition was completed, it was kept warm for 30 minutes, and then 60% of monomer I was added dropwise into the reactor within 4 hours, and after the dropwise addition was completed, it was kept warm for 25 minutes to obtain Lotion;

(c) Dissolve the remaining emulsifier and initiator in the remaining water to make a mixed solution, add the monomer II to the monomer I dropwise and keep stirring while mixing the mixture of the above monomer I and monomer II and the remaining The mixed solution made of water, emulsifier and initiator is continuously added dropwise to the emulsion obtained in step (c) within 1 hour, reacted for 1 hour after the dropwise addition, and then heated to 85°C for 2 hours, then cooled to 50° C., and the material was filtered to obtain a fluorosilicon-modified acrylate polymer emulsion.

Measure the pH value of the reaction system every 30 minutes during the reaction in step (c), and use sodium bicarbonate to adjust the pH value of the reaction system to 6.5 when the pH value is outside the range of 6.0-7.0.

(2) Preparation of superhydrophobic modified SiO ₂ sol;

(a) Add 10 parts of ethyl orthosilicate dropwise to a mixed solution consisting of 10 parts of deionized water, 15 parts of tetraethylammonium hydroxide and 80 parts of ethanol, and hydrolyze at 70°C for 1 hour to prepare hydrolyzate A;

(b) Add 5 parts of methyltriethoxysilane dropwise to hydrolyzate A, and then hydrolyze for 3 hours to make hydrolyzate B.

(c) Add 2 parts of octadecyltriethoxysilane to the hydrolyzate B, then hydrolyze for 6h, keep it warm for 18h and then cool down to room temperature to obtain a modified SiO ₂ sol. The system is kept stirring during the whole process.

(3) Preparation of glass superhydrophobic surface

The steps of the spin coating method are as follows: the glass sheet is spin-coated with fluorosilicon modified acrylate emulsion in a spin coater for 8 minutes, taken out, cured at room temperature for 2.5 h, and then the cured glass sheet is spin-coated with modified SiO ₂ sol in a spin coater. After 4 min, the spin coating was repeated 4 times after the surface was dry, and finally placed in an oven at 120 °C for 1.5 h.

In the preparation process of the fluorosilicone-modified acrylate emulsion, the average particle size of the step (b) is 60nm, and the final average particle size is 114nm, with a narrow particle size distribution. Transmission electron microscopy (TEM) analysis showed that latex particles were uniform in size and spherical in shape. Elemental analysis shows that from 60nm to 114nm, the content of fluorine and silicon in the particles increases gradually. Scanning electron microscopy (SEM) analysis showed that the emulsion had good film-forming properties, and the film was compact without phase separation. Infrared analysis (FTIR) of the modified SiO ₂ sol prepared by emulsion coating with a water contact angle of 114° showed that the SiO ₂ particles had been grafted with methyl groups and octadecyl groups. Atomic force microscope (AFM) analysis and static water contact angle test (WCA) test were carried out on the prepared coating film. The results showed that the surface of the coating film had a micro-nano double-rough structure, and the water contact angle was 160°, which was superhydrophobic.

Example 4:

(1) Preparation of fluorosilicone modified acrylate emulsion;

(a) The components of the fluorosilicone-modified acrylate emulsion are shown in Table 4 below. Mix alkyl methacrylate and alkyl acrylate in the step components to make monomer I, hydroxyalkyl acrylate or hydroxyalkyl methacrylate, organosiloxane, fluorine-containing alkyl acrylate or Alkyl fluoromethacrylate is mixed to make monomer II;

(b) Add 75% of water in step (a), 85% of the mass of the mixture of SDS and HAPS, 80% of sodium persulfate, and sodium dihydrogen phosphate into the reaction kettle, stir for 20 minutes and then heat up to 75°C, take a single 15% of monomer I was added to the reactor in 15 minutes, and after the dropwise addition was completed, it was incubated for 20 minutes, and then 65% of monomer I was added dropwise to the reactor within 2.5 hours, and after the dropwise addition was completed, it was incubated for 30 minutes to obtain Lotion;

(c) Dissolve the remaining emulsifier and initiator in the remaining water to make a mixed solution, add the monomer II to the monomer I dropwise and keep stirring while mixing the mixture of the above monomer I and monomer II and the remaining The mixed solution made of water, emulsifier and initiator is continuously added dropwise to the emulsion obtained in the above steps within 1.5 hours, reacted for 0.5 hours after the dropwise addition, and then heated to 80°C for 1.5 hours, then cooled to 40°C °C, the material was filtered out to obtain a fluorosilicon-modified acrylate polymer emulsion.

Measure the pH value of the reaction system every 40 minutes during the reaction in step (c), and use sodium bicarbonate to adjust the pH value of the reaction system to 6.5 when the pH value is outside the range of 6.0 to 7.0.

(2) Preparation of superhydrophobic modified SiO ₂ sol;

(a) Add 10 parts of butyl orthosilicate dropwise to a mixed solution consisting of 20 parts of deionized water, 15 parts of ammonia water, and 80 parts of butanol, and hydrolyze at 50°C for 4 hours to prepare hydrolyzate A;

(b) Add 5 parts of methyltributoxysilane dropwise to hydrolyzate A, and then hydrolyze for 4 hours to make hydrolyzate B.

(c) Add 4 parts of heptadecylfluorodecyltrimethoxysilane to the hydrolyzate B, hydrolyze for 4h, keep it warm for 24h and cool down to room temperature to obtain the modified SiO ₂ sol. The system was kept stirring throughout the process.

(3) Preparation of glass superhydrophobic surface

Immerse the glass sheet in the fluorosilicon modified acrylate emulsion for 8 minutes by dipping and pulling method, take it out, cure it at room temperature for 2.5 hours, then immerse the glass sheet in the modified SiO ₂ sol for 8 minutes, repeat the pulling 4 times, at 120°C Put it in the oven for 1.5h, and then get a superhydrophobic coating film.

In the preparation process of the fluorosilicone-modified acrylate emulsion, the average particle size of the step (b) is 68nm, and the final average particle size is 118nm, with a narrow particle size distribution. Transmission electron microscopy (TEM) analysis showed that latex particles were uniform in size and spherical in shape. Elemental analysis shows that from 68nm to 118nm, the content of fluorine and silicon in the particles increases gradually. Scanning electron microscopy (SEM) analysis showed that the emulsion had good film-forming properties, and the film was compact without phase separation. Infrared analysis (FTIR) of the modified SiO ₂ sol prepared by emulsion coating with a water contact angle of 110° showed that the SiO ₂ particles had been grafted with methyl and heptadecafluorodecyl groups. Atomic force microscope (AFM) analysis and static water contact angle test (WCA) test were carried out on the prepared coating film. The results showed that the surface of the coating film had a micro-nano double rough structure, and the water contact angle was 158°, which was superhydrophobic.

Example 5:

(1) Preparation of fluorosilicone modified acrylate emulsion;

(a) The components of the fluorosilicone-modified acrylate emulsion are shown in Table 5 below. Mix alkyl methacrylate and alkyl acrylate in the step components to make monomer I, hydroxyalkyl acrylate or hydroxyalkyl methacrylate, organosiloxane, fluorine-containing alkyl acrylate or Alkyl fluoromethacrylate is mixed to make monomer II;

(b) Add 60% of water in step (a), 70% of the mass of the mixture of SDS and AMPS-NH ₄ , 65% of potassium persulfate and sodium bicarbonate into the reaction kettle, stir for 15 minutes and then heat up to 77 °C, Take 15% of the monomer I and add it to the reactor in 25 minutes. After the dropwise addition, keep it warm for 25 minutes, then add 60% of the monomer I dropwise into the reactor within 3 hours, and keep it warm for 25 minutes after the dropwise addition. , to obtain emulsion;

(c) Dissolve the remaining emulsifier and initiator in the remaining water to make a mixed solution, add the monomer II to the monomer I dropwise and keep stirring while mixing the mixture of the above monomer I and monomer II and the remaining The mixed solution made of water, emulsifier and initiator is continuously added dropwise to the emulsion obtained in step (c) within 1.5 hours. After the dropwise addition is completed, react for 1 hour, then raise the temperature to 82°C and keep it for 1 hour, then cool down to 45° C., and the material was filtered to obtain a fluorosilicon-modified acrylate polymer emulsion.

Measure the pH value of the reaction system every 30 minutes during the reaction in step (c), and use sodium bicarbonate to adjust the pH value of the reaction system to 6.5 when the pH value is outside the range of 6.0-7.0.

(2) Preparation of superhydrophobic modified SiO ₂ sol;

(a) Add 5 parts of ethyl orthosilicate dropwise to a mixed solution consisting of 20 parts of deionized water, 10 parts of tetraethylammonium hydroxide, and 50 parts of ethanol, and hydrolyze at 65°C for 3 hours to prepare hydrolyzate A;

(b) Add 2 parts of methyltrimethoxysilane dropwise to hydrolyzate A, and then hydrolyze for 3 hours to make hydrolyzate B.

(c) Add 3 parts of dodecyltrimethoxysilane to the hydrolyzate B, and then hydrolyze for 3h, keep it warm for 18h and then cool down to room temperature to obtain a modified SiO ₂ sol. The system is kept stirring during the whole process.

(3) Preparation of glass superhydrophobic surface

Immerse the glass sheet in the fluorosilicon modified acrylate emulsion for 5 minutes by dipping and pulling method, take it out, cure it at room temperature for 2 hours, then immerse the glass sheet in the modified SiO ₂ sol for 6 minutes, repeat the pulling 4 times, and put it in an oven at 115°C Placed in the middle for 2h, a super-hydrophobic coating film is obtained.

In the preparation process of the fluorosilicone-modified acrylate emulsion, the average particle size of the step (2) is 66nm, and the final average particle size is 117nm, with a narrow particle size distribution. Transmission electron microscopy (TEM) analysis showed that latex particles were uniform in size and spherical in shape. Elemental analysis shows that from 66nm to 117nm, the content of fluorine and silicon in the particles increases gradually. Scanning electron microscopy (SEM) analysis showed that the emulsion had good film-forming properties, and the film was compact without phase separation. The water contact angle of emulsion coating film is 114°

Infrared analysis (FTIR) of the prepared modified SiO ₂ sol showed that the SiO ₂ particles had been grafted with methyl groups and dodecyl groups. Atomic force microscope (AFM) analysis and static water contact angle test (WCA) test were carried out on the prepared coating film. The results showed that the surface of the coating film had a micro-nano double rough structure, and the water contact angle was 157°, which was superhydrophobic.

Claims (9)

1. a preparation method of glass super-hydrophobic surface, is characterized in that, the preparation method of described glass super-hydrophobic surface is the following steps: (1) Preparation of fluorosilicone modified acrylate emulsion, (2) Preparation of modified SiO ₂ sol, (3) Preparation of glass superhydrophobic surface. 2. A method for preparing a glass superhydrophobic surface according to claim 1, wherein the fluorine-silicon-modified acrylate emulsion in step (1) is prepared from the following components, and the specific steps are as follows: (a) The parts by weight of the components of the fluorosilicon-modified acrylate emulsion are: (b) Weigh the above-mentioned components according to the number of components, mix alkyl methacrylate and alkyl acrylate to make monomer I, hydroxyalkyl acrylate or hydroxyalkyl methacrylate, organic Siloxane, fluorine-containing alkyl acrylate or fluorine-containing alkyl methacrylate are mixed to form monomer II; (c) Add 55%~75% of water, 50%~80% of emulsifier, 60%~85% of initiator and pH regulator into the reaction kettle, stir for 10~20 minutes and then heat up to 75 ~80 ℃, take 10%~20% of the monomer I and add it to the reaction kettle for 15~30 minutes, after the dropwise addition is completed, keep it warm for 15~30 minutes, and then add 50%~70% of the monomer I at 2.5 Add dropwise to the reaction kettle within ~4 hours, after the dropwise addition, keep warm for 15~30 minutes to obtain the emulsion; (d) Dissolve the remaining emulsifier and initiator in the remaining water to make a mixed solution, add the monomer II to the monomer I dropwise and keep stirring while mixing the mixture of the above monomer I and monomer II and the remaining The mixed solution made of water, emulsifier and initiator is continuously added dropwise to the emulsion obtained in step (c) within 0.5~1.5 hours; after the dropwise addition, react for 0.5~1 hour, and then heat up to 80~85°C Keep it warm for 1-2 hours, then lower the temperature to 40-50°C, filter and discharge the material to obtain a fluorosilicon-modified acrylate polymer emulsion. 3. the preparation method of a kind of glass superhydrophobic surface according to claim 2, is characterized in that, in each component of described fluorosilicon modified acrylate emulsion: Described alkyl methacrylate is selected from methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, pentyl methacrylate, hexyl methacrylate, methacrylic acid One or several mixtures in any proportion of isooctyl esters; The alkyl acrylate is selected from methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, hexyl acrylate, isooctyl acrylate or a mixture of several in any proportion; The organosiloxane is selected from vinyltrimethoxysilane, vinyltriethoxysilane, vinyltributoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methoxysilane Acryloyloxypropyltriethoxysilane or a mixture of several in any proportion; Described hydroxyalkyl acrylate or hydroxyalkyl methacrylate is selected from 2-hydroxyethyl acrylate, 3-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 5-hydroxypentyl acrylate, A mixture of one or more of 6-hydroxyhexyl acrylate, 2-hydroxyethyl methacrylate, and 3-hydroxypropyl methacrylate in any proportion; The fluorine-containing alkyl acrylate or fluorine-containing alkyl methacrylate is selected from hexafluorobutyl acrylate, hexafluorobutyl methacrylate, trifluoroethyl acrylate, trifluoroethyl methacrylate, Difluoroheptyl, dodecafluoroheptyl methacrylate, tridecafluorooctylethyl acrylate, tridecafluorooctylethyl methacrylate, hexafluorobutyl acrylate, hexafluorobutyl methacrylate, decafluorooctyl acrylate One of trifluorooctyl, trifluorooctyl methacrylate, dodecafluoroheptyl acrylate, and dodecafluoroheptyl methacrylate; Described initiator is selected from persulfate system; The emulsifier is a compound of an anionic emulsifier and a reactive emulsifier, and the reactive emulsifier is 1 to 4 times the mass of the anionic emulsifier, wherein the anionic emulsifier is selected from disodium dodecyl diphenyl ether sulfonate, Sodium dodecylbenzene sulfonate, sodium lauryl sulfate, or a mixture of several in arbitrary proportions; the reactive emulsifier is selected from 2-acrylamido-2-methyl-propylsulfonic acid sodium salt, 2-Acrylamido-2-methyl-propyl ammonium sulfonate, sodium 1-allyloxy-2-hydroxypropyl sulfonate, sodium 2-acrylamido tetradecane sulfonate, methacrylic acid One or several mixtures in any proportion of sodium hydroxypropanesulfonate; The pH regulator is selected from sodium bicarbonate, potassium bicarbonate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, or a mixture of several in any proportion; Described water is deionized water. 4. A method for preparing a glass superhydrophobic surface according to claim 2, wherein the mass ratio of monomer I to monomer II in step (b) during the preparation of the fluorosilicon-modified acrylate emulsion is 2 ~4:1, step (d) measure the pH value of the reaction system every 20-40 minutes during the reaction process, and adjust the pH value between 6.0 and 7.0. In this step, use the same substance as the pH regulator to adjust the pH of the reaction system value. 5. the preparation method of a kind of superhydrophobic surface of glass according to claim 1, is characterized in that, in step (2), modified _SiO sol is prepared from the following components, and the specific steps of preparation are as follows, (a) The parts by weight of the components of the modified SiO _sol are:

(b) Weigh the above-mentioned components according to the number of each component, add the alkyl orthosilicate dropwise into the mixed solution composed of water, alkaline catalyst and alcohol, and hydrolyze it at 50-70°C for 1-6 hours to prepare into hydrolyzate A; (c) Add methyltrialkoxysilane dropwise to the above-mentioned hydrolyzate A, and then hydrolyze for 1~6h to make hydrolyzate B; (d) Add long-chain alkyltrialkoxysilane or long-chain fluorine-containing alkyltrialkoxysilane into hydrolyzate B, then hydrolyze for 1~6h, keep warm for 12~24h, then cool down to room temperature to obtain modified SiO ₂ sol. The room temperature is 25°C. 6. the preparation method of a kind of glass superhydrophobic surface according to claim 4, is characterized in that, described modified _SiO In each component of sol: The alkyl orthosilicate is selected from one of methyl orthosilicate, ethyl orthosilicate, and butyl orthosilicate; Described alcohol is selected from the one in methanol, ethanol, butanol; The methyltrialkoxysilane is selected from one of methyltrimethoxysilane, methyltriethoxysilane and methyltributoxysilane; The long-chain alkyltrialkoxysilane or long-chain fluorine-containing alkyltrialkoxysilane is selected from octyltrimethoxysilane, dodecyltrimethoxysilane, tridecafluorooctyltrimethoxy Silane, Hexadecyltrimethoxysilane, Octadecyltrimethoxysilane, Perfluorooctyltrimethoxysilane, Heptadecylfluorodecyltrimethoxysilane, Octyltriethoxysilane, Dodecane Triethoxysilane, Tridecafluorooctyltriethoxysilane, Hexadecyltriethoxysilane, Octadecyltriethoxysilane, Perfluorooctyltriethoxysilane, Seventeen One or more of fluorodecyltriethoxysilane; Described basic catalyst is selected from the one in ammoniacal liquor, tetramethylammonium hydroxide, tetraethylammonium hydroxide; Described water is deionized water. 7. according to the preparation method of a kind of glass superhydrophobic surface described in claim 5 or 6, it is characterized in that, described modified _SiO In each component of sol: in described alcohol and alkyl orthosilicate The alcohol with the same alkyl part, the methyltrialkoxysilane is the same as the alkyl part in the alcohol. 8. the preparation method of a kind of glass superhydrophobic surface according to claim 5, is characterized in that, described modified SiO _sol preparation process whole process system keeps stirring. 9 . The method for preparing a glass superhydrophobic surface according to claim 1 , wherein the preparation of the glass superhydrophobic surface in step (3) adopts a spin coating method or a dipping and pulling method.