阅读说明：本技术 一种具有自修复超疏水功能柔性基底的制备方法 (Preparation method of flexible substrate with self-repairing super-hydrophobic function ) 是由 邓字巍 王会超 汪娟丽 曹静 付诺 于 2021-08-23 设计创作，主要内容包括：一种具有自修复超疏水功能柔性基底的制备方法,将作为柔性基底的布料置于稀释后的植酸水溶液中浸泡后,向该植酸水溶液中加入3-氨基丙基基团-封端的聚二甲基硅氧烷乳液并搅拌均匀,得到混合液。用该混合液继续浸泡布料。对经过浸泡后的布料冲洗烘干,得到具有自修复超疏水功能柔性基底。本发明解决了现有技术中超疏水材料制备复杂、实施工艺过程耗时、污染环境、生产成本高的问题,并且得到的超疏水材料表面具有自愈型性能。测试结果表明,本发明基材表面变得粗糙,Si元素的含量明显上升,还含有P元素,表明植酸与3-氨基丙基基团-封端的聚二甲基硅氧烷的反应物沉积到棉布表面,从而使布料具有了超疏水性。(A preparation method of a flexible substrate with a self-repairing super-hydrophobic function comprises the steps of soaking cloth serving as the flexible substrate in diluted phytic acid aqueous solution, adding 3-aminopropyl group-terminated polydimethylsiloxane emulsion into the phytic acid aqueous solution, and uniformly stirring to obtain a mixed solution. The mixed solution is used for continuously soaking the cloth. And washing and drying the soaked cloth to obtain the flexible substrate with the self-repairing super-hydrophobic function. The invention solves the problems of complex preparation of the super-hydrophobic material, time-consuming implementation process, environmental pollution and high production cost in the prior art, and the surface of the obtained super-hydrophobic material has self-healing performance. The test result shows that the surface of the base material of the invention becomes rough, the content of Si element is obviously increased, and the invention also contains P element, which shows that the reactant of phytic acid and 3-aminopropyl group-terminated polydimethylsiloxane is deposited on the surface of cotton cloth, thereby the cloth has super-hydrophobicity.)

1. A preparation method of a flexible substrate with a self-repairing super-hydrophobic function comprises the following steps of (1) preparing a flexible substrate by using pure cotton cloth, silk and polyester fiber cloth; the method is characterized by comprising the following specific processes:

step 1, diluting phytic acid aqueous solution:

mixing a phytic acid aqueous solution with the concentration of 70% and ultrapure water according to the volume ratio of 1: 80-120, uniformly mixing and stirring to obtain a diluted phytic acid aqueous solution;

step 2, preparing 3-aminopropyl group-terminated polydimethylsiloxane emulsion:

3-aminopropyl group-terminated polydimethylsiloxane and ultrapure water in a volume ratio of 3: mixing 500-2000 and uniformly dispersing by ultrasonic to obtain polydimethylsiloxane emulsion for later use;

step 3, preparing the flexible substrate with self-repairing super-hydrophobic function and super-hydrophobicity:

soaking a flexible substrate to be treated in a diluted phytic acid aqueous solution for 3-60 min to enable the flexible substrate to be completely soaked by the phytic acid aqueous solution; adding the obtained 3-aminopropyl group-terminated polydimethylsiloxane emulsion into a phytic acid aqueous solution soaked with a flexible substrate to form a mixed soaking solution, and continuously soaking the flexible substrate; the phytic acid aqueous solution comprises the following components: 3-aminopropyl group-terminated polydimethylsiloxane emulsion ═ 1: 1; during soaking, stirring at a stirring speed of 500-800 r/min for 1-15 min, and standing for 1-8 h;

after standing, taking the flexible substrate out of the mixed solution, repeatedly washing the flexible substrate twice with absolute ethyl alcohol with the concentration of more than 99.7 percent, and washing the flexible substrate twice with distilled water;

and placing the washed pure cotton cloth into a utensil, putting the utensil into an oven, and drying the utensil at the temperature of 100-130 ℃ for 0.5-1 h to obtain the self-healing flexible substrate with the super-hydrophobic function.

2. The method for preparing the self-healing super-hydrophobic flexible substrate according to claim 1, wherein the surface of the self-healing flexible substrate with the super-hydrophobic function is transparent.

3. The method for preparing the flexible substrate with the self-repairing superhydrophobic function according to claim 1, wherein when pure cotton cloth is adopted as the substrate, the volume ratio of the phytic acid aqueous solution to the ultrapure water is 1: 80-120 parts; when polyester is used as a substrate, the volume ratio of the phytic acid aqueous solution to ultrapure water is 1: 60-130; when silk is used as a substrate, the volume ratio of the phytic acid aqueous solution to the ultrapure water is 1: 50 to 200.

4. The method for preparing the flexible substrate with the self-repairing superhydrophobic function according to claim 1, wherein when pure cotton cloth is adopted as the substrate, the volume ratio of polydimethylsiloxane to ultrapure water is 3: 500 to 2000;

when polyester is used as the substrate, the volume ratio of the polydimethylsiloxane to the ultrapure water is 3: 500 to 2000; when silk is used as a substrate, the volume ratio of polydimethylsiloxane to ultrapure water is 3: 300 to 3000.

5. The method for preparing the flexible substrate with self-repairing superhydrophobic function according to claim 1,

when the pure cotton cloth is used as a substrate, the pure cotton cloth is soaked in the phytic acid aqueous solution for 3-15 min and is soaked in the mixed solution for 1-2 h; when the polyester fiber is used as a substrate, the polyester fiber is soaked in the phytic acid aqueous solution for 5-20 min, and the soaking time in the mixed solution is 1-4 h; when silk is used as a substrate, the silk is soaked in phytic acid aqueous solution for 10-60 min, and the soaking time in the mixed solution is 1-8 h.

6. The method for preparing the flexible substrate with the self-repairing superhydrophobic function according to claim 1, wherein when pure cotton cloth is adopted as the substrate, the drying temperature of the pure cotton cloth is 120 ℃, and the drying time is 0.5 h; when the polyester fiber is used as a substrate, the drying temperature of the polyester fiber is 100 ℃, and the drying time is 1 h; when silk is used as a substrate, the drying temperature of the silk is 130 ℃, and the drying time is 0.8 h.

Technical Field

The invention relates to the technical field of flexible substrate preparation, in particular to a preparation method of a flexible substrate with a self-repairing super-hydrophobic function.

Background

The super-hydrophobic material refers to a material of which the contact angle of the surface with water in air exceeds 150 degrees. The super-hydrophobic material has wide application potential in the fields of personal protection articles, oil-water separation, ice prevention, biological adhesion prevention and the like due to the properties of super-hydrophobicity and the like on the surface. Although preparation and application of a large amount of super-hydrophobic materials are expanded to various aspects in real life, for example, methods for preparing super-hydrophobic surfaces are proposed in inventions and creations such as CN125756A and CN1876292A, most of hydrophobic coatings which are successful in the prior art are prepared on hard substrates. In real life, the preparation of transparent hydrophobic coatings on soft substrate materials is more urgent.

The traditional method mainly involves two preparation processes: (1) introducing a multilevel structure on the surface of a substrate material, and introducing some low-surface-energy substances on the surface of the multilevel structure through chemical modification to finally form a flexible substrate material with a super-hydrophobic coating surface; for example: in the article of Fabric of high throughput Hydrophobic Coatings from Hollow silicon Nanoparticles, Transparent, Hydrophobic Surfaces from One-Step Spin Coating of Hydrophobic Nanoparticles, A Self-textured Ethyl to Surface-core silicon Nanoparticles for Hydrophobic Coatings, a sol-gel Route was used to form some of the inorganic Nanoparticles SiO on the woven fabric₂Or TiO₂And forming a multi-level structure on the surface of the substrate, introducing some low-surface substances on the surface of the multi-level structure through chemical vapor deposition or other chemical modification, and finally forming the substrate material with the super-hydrophobic characteristic. (2) The super-hydrophobic material is formed by directly constructing a base material by adopting a low-surface-energy substance. For example: electrospun ports StrucIn the tube fibre Film with High Oil addition Capacity, Wu et al directly use the electrostatic spinning method to form the super-hydrophobic fiber or porous membrane material from some substances with lower surface energy. There are many reports of the methods for preparing super-hydrophobic coatings on flexible substrates disclosed in the patent application, for example, in CN100595373C, the method of the invention adopts chloroauric acid and citric acid to prepare super-hydrophobic pure cotton cloth from cotton cloth containing 80-100% of fibers, and then adopts dodecyl mercaptan to prepare the super-hydrophobic pure cotton cloth, so that the surface of the super-hydrophobic pure cotton cloth has super-hydrophobic characteristics. Although the hydrophilic cotton cloth is prepared into the super-hydrophobic cotton cloth, the super-hydrophobic cotton cloth is expensive due to the use of precious metals, and the prepared pure cotton cloth has no self-repairing characteristic and cannot be recovered after the super-hydrophobicity on the surface is damaged, so that the waste of resources is caused.

To achieve the functionality of superhydrophobic surface self-healing, researchers have done a great deal of work in this regard, such as: in the bioinsed self-healing super-hydrophobic coatings article, Li et al use Chemical Vapor Deposition (CVD) to deposit hydrophobic materials in porous polymers to make superhydrophobic surfaces, and when the surfaces are damaged, low surface energy materials in the middle of the polymer spontaneously aggregate to the damaged sites to restore the hydrophobic character; in addition to strategies for repairing surface chemical constituents, Manna U et al in the Self-Healing and Recovery of Damaged cosmetic Features aid by an Unlikely Source article can achieve the goal of Self-Healing by reconstructing the micro-roughness of the surface. Currently, methods based on shape memory materials and chemical methods have been developed to restore their surface structure and thus their hydrophobicity. Although various methods for preparing self-healing superhydrophobic surfaces have been successfully developed, these methods suffer from time consuming, complex operation, high production costs, and environmental unfriendliness. Therefore, researchers urgently need to develop a method for constructing a super-hydrophobic surface, which is efficient, rapid, environment-friendly and has a self-repairing capability, and can be widely applied in practice.

Disclosure of Invention

In order to overcome the defects of complex operation, high production cost and environmental pollution in the prior art, the invention provides a preparation method of a flexible substrate with a self-repairing super-hydrophobic function.

The flexible substrate is made of pure cotton cloth, silk and polyester fiber cloth.

The specific process of the invention is as follows:

step 1: diluting the phytic acid aqueous solution:

mixing a phytic acid aqueous solution with the concentration of 70% and ultrapure water according to the volume ratio of 1: 80-120, and uniformly mixing and stirring to obtain the diluted phytic acid aqueous solution.

When pure cotton cloth is adopted as a substrate, the volume ratio of the phytic acid aqueous solution to the ultrapure water is 1: 80-120 parts; when polyester is used as a substrate, the volume ratio of the phytic acid aqueous solution to ultrapure water is 1: 60-130; when silk is used as a substrate, the volume ratio of the phytic acid aqueous solution to the ultrapure water is 1: 50 to 200.

Step 2: preparing 3-aminopropyl group-terminated polydimethylsiloxane emulsion:

3-aminopropyl group-terminated polydimethylsiloxane and ultrapure water in a volume ratio of 3: and (3) mixing 500-2000, and uniformly dispersing by using ultrasonic waves to obtain the polydimethylsiloxane emulsion for later use.

When pure cotton cloth is adopted as a substrate, the volume ratio of the polydimethylsiloxane to the ultrapure water is 3: 500 to 2000; when polyester is used as the substrate, the volume ratio of the polydimethylsiloxane to the ultrapure water is 3: 500 to 2000; when silk is used as a substrate, the volume ratio of polydimethylsiloxane to ultrapure water is 3: 300 to 3000.

And step 3: preparing the super-hydrophobic flexible substrate with the self-repairing super-hydrophobic function.

And (3) placing the flexible substrate to be treated in the diluted phytic acid aqueous solution for soaking for 3-60 min, so that the flexible substrate is completely soaked by the phytic acid aqueous solution. Adding the obtained 3-aminopropyl group-terminated polydimethylsiloxane emulsion into a phytic acid aqueous solution soaked with a flexible substrate to form a mixed soaking solution, and continuously soaking the flexible substrate; the phytic acid aqueous solution comprises the following components: 3-aminopropyl group-terminated polydimethylsiloxane emulsion ═ 1: 1. and during soaking, stirring at a stirring speed of 500-800 r/min for 1-15 min, and standing for 1-8 h.

And after standing, taking the flexible substrate out of the mixed solution, repeatedly washing twice with absolute ethyl alcohol with the concentration of more than 99.7 percent, and washing twice with distilled water.

When the pure cotton cloth is used as a substrate, the pure cotton cloth is soaked in the phytic acid aqueous solution for 3-15 min and is soaked in the mixed solution for 1-2 h; when the polyester fiber is used as a substrate, the polyester fiber is soaked in the phytic acid aqueous solution for 5-20 min, and the soaking time in the mixed solution is 1-4 h; when silk is used as a substrate, the silk is soaked in phytic acid aqueous solution for 10-60 min, and the soaking time in the mixed solution is 1-8 h.

And placing the washed pure cotton cloth into a utensil, putting the utensil into an oven, and drying the utensil at the temperature of 100-130 ℃ for 0.5-1 h to obtain the self-healing flexible substrate with the super-hydrophobic function.

When the pure cotton cloth is used as the substrate, the drying temperature of the pure cotton cloth is 120 ℃, and the drying time is 0.5 h; when the polyester fiber is used as a substrate, the drying temperature of the polyester fiber is 100 ℃, and the drying time is 1 h; when silk is used as the substrate, the drying temperature of the silk is 130 ℃, and the drying time is 0.8h

The surface of the obtained self-healing flexible substrate with the super-hydrophobic function is transparent.

The invention adopts phytic acid with six reactive groups to construct a multilevel structure, and introduces 3-aminopropyl group-terminated polydimethylsiloxane as a low surface energy substance to realize the efficient, rapid, environment-friendly and self-repairing super-hydrophobic surface construction.

In order to achieve the purpose, the flexible substrate is soaked in an aqueous phytic acid solution, the phytic acid is enabled to act with active groups such as hydroxyl groups in the flexible substrate, the phytic acid is fixed on the surface of the flexible substrate, then the 3-aminopropyl group-terminated polydimethylsiloxane is dispersed into uniform emulsion by an ultrasonic cell crusher and added into the aqueous phytic acid solution soaked with the flexible substrate, and the amino group of the 3-aminopropyl group-terminated polydimethylsiloxane is subjected to condensation reaction with the phosphate group of the phytic acid on the flexible substrate so as to be deposited on the surface of the flexible substrate and enable the flexible substrate to be super-hydrophobic. The self-repairing characteristic is that after the flexible substrate is subjected to plasma treatment, the surface superhydrophobicity is destroyed, the surface free energy is increased, 3-aminopropyl group-terminated polydimethylsiloxane hydrophobic molecules below the damaged surface of the flexible substrate have the tendency of spontaneously migrating to the surface so as to reduce the surface free energy, and meanwhile, hydrophilic polar groups are hidden inside the flexible substrate. Heating accelerates this process, causing the surface of the flexible substrate to be refilled with low surface energy 3-aminopropyl group-terminated polydimethylsiloxane molecules, resulting in a significant reduction in the surface free energy of the flexible substrate, eventually restoring its superhydrophobicity.

The invention overcomes and solves the problems of complex preparation, time-consuming implementation process, environmental pollution and high production cost of the super-hydrophobic material in the prior art, and the surface of the obtained super-hydrophobic material has self-healing performance.

In order to verify the effect of the invention, the microstructure, the performance and the effect of the obtained flexible substrate with the super-hydrophobic function are tested, and the test process and the test result are as follows:

the microstructure of the prepared cotton cloth is characterized by a scanning electron microscope, and fig. 1(a \ b) is a scanning image of the cotton cloth which is not prepared and the cotton cloth which is prepared respectively, so that the surface of the base material can be seen to be rougher, the content of Si element can be seen to be obviously increased from the energy spectrum of fig. 2, and the appearance of P element shows that reactants of phytic acid and 3-aminopropyl group-terminated polydimethylsiloxane are deposited on the surface of the cotton cloth, so that the material is hydrophobic. From the scanned graph of fig. 3, it can be seen that the topography of the substrate surface after the plasma treatment and the self-recovery is not changed, but from the energy spectrum of fig. 4, it can be seen that the content of the Si element is reduced after the plasma treatment and the content of the Si element is increased after the self-recovery, and the recovery of the hydrophobic property of the flexible substrate depends on the migration of the hydrophobic silane to the material surface.

In addition, the prepared pure cotton cloth is also subjected to hydrophobic property, self-repairing property and air permeability test:

1. and (3) hydrophobic property test:

video optical contact angle measuring instrument (Dataphysics OCA 20): the method is used for testing the wettability of the surface of the material. And randomly selecting 5 different positions on the surface of the sample to measure the contact angle of the material, and then averaging to obtain the contact angle of the material, wherein the volume of the water drop in the measurement process is 3L.

As shown in figure 1, the prepared cotton cloth, polyester fiber and silk have the hydrophobic angle of more than 150 degrees, which indicates that the prepared flexible substrate is super-hydrophobic.

2. Test for air permeability

The prepared pink cotton cloth was subjected to air permeability test, and the test data are shown in table 1 below, which indicates that the prepared sample is more air permeable.

TABLE 1

Sample (I)	Air permeability ml/(cm)3·h)
		Pink original sample	7369.498
Pink prepared sample	27906.977

The air permeability of the flexible substrate prepared according to the results of table 1 was superior to that of the original flexible substrate.

3. Self-healing feature

Treating the super-hydrophobic surface by adopting an air plasma etching method:

air plasma etching: A1X 1cm superhydrophobic sample was cut. The sample was placed in an air atmosphere and etched for 5min using an air plasma with a power of 100W. And measuring the contact angle of the treated substrate by using a video optical contact angle measuring instrument. And (3) placing the treated substrate in a 120 ℃ oven for 0.5h, taking out, carrying out multiple plasma etching-illumination repair tests on the same sample, and recording the water contact angle, the final recyclable times and the heating time of the sample after each repair. From the test results, it can be seen that the surface of the prepared cotton cloth becomes hydrophilic after the treatment, regains the super-hydrophobic property after the heating and can be repeated 10 times.

Characterization of the prepared flexible substrate is carried out, fig. 4(a, b) are scanned drawings of an unprepared flexible substrate and a prepared flexible substrate respectively, it can be seen that the surface of the base material becomes rougher, the content of Si element can be seen to be obviously increased from the energy spectrum of fig. 5, and the appearance of P element shows that reactants of phytic acid and 3-aminopropyl group-terminated polydimethylsiloxane are deposited on the surface of the flexible substrate, so that the flexible substrate is hydrophobic.

From the scan of fig. 6, the topography of the substrate surface after plasma treatment and self-healing did not change, but from the energy spectrum of fig. 7, it is seen that the content of Si element decreased after plasma treatment and increased after self-healing, and it can be seen that the recovery of the hydrophobic property of the material depends on the migration of hydrophobic silane to the surface of the flexible substrate. The self-healing mechanism is presumed as: the surface appearance of the flexible substrate after air plasma treatment and heating repair is not changed greatly, the surface is still rough, but the surface element composition and wettability are changed greatly, and the characteristic peak of Si is reduced after plasma cleaning, because 3-aminopropyl group-terminated polydimethylsiloxane hydrophobic molecules on the surface are cleaned after plasma treatment. In addition, after plasma treatment, high-activity polar groups (such as hydroxyl, amino and carbonyl) are introduced into the surface of the coating, so that the surface free energy is greatly increased, and the rough surface is combined with higher surface energy, thereby finally enabling the surface to have super-hydrophilicity. After the flexible substrate treated by the plasma is self-repaired, the characteristic peak of Si is increased, and the contact angle of water is also increased to more than 150 degrees, so that the super-hydrophobic property is recovered. This is because the surface free energy is increased after the plasma treatment, and 3-aminopropyl group-terminated polydimethylsiloxane hydrophobic molecules under the damaged surface of the flexible substrate have a tendency to spontaneously migrate toward the surface to lower the surface free energy, while hydrophilic polar groups are hidden inside the flexible substrate. Heating accelerates this process, causing the surface of the flexible substrate to be refilled with the low surface energy molecules of the 3-aminopropyl group-terminated polydimethylsiloxane, resulting in a significant reduction in the surface free energy of the flexible substrate, eventually restoring its superhydrophobicity.

4. Color difference

The pink flexible substrates before and after the preparation were subjected to color difference test, and the test data are shown in table 2 below, wherein Δ L, Δ a, and Δ b are differences between lightness L and chroma indexes a, b between the prepared sample and the blank sample, and Δ E indicates that the measurement shows that the color difference between the prepared sample and the blank sample is 0.68, and the color difference is small and cannot be distinguished by naked eyes.

TABLE 2

Number of times	△L*	△a*	△b*	△E*
					1	-0.70	-0.50	0.16	0.88
2	0.18	-0.39	0.30	0.52
					3	-0.32	-0.13	0.62	0.71
4	-0.17	-0.33	0.12	0.39
					5	-0.81	-0.21	0.34	0.90
Mean value of	--	--	--	0.68

The results shown in Table 2 indicate that the color difference of the modified flexible substrate is below 1 and cannot be distinguished by naked eyes.

Drawings

FIG. 1 is a schematic representation of the hydrophobicity of a self-healing superhydrophobic functional flexible substrate as determined by a video optical contact angle determinator; wherein, figure 1a is the cotton cloth at the video optical contact angle of 152.0 + -1.8 deg. hydrophobicity, figure 1b is the polyester fiber at the video optical contact angle of 151.5 + -1.0 deg. hydrophobicity, figure 1c is the silk at the video optical contact angle of 151.8 + -1.4 deg. hydrophobicity.

FIG. 2 is a mapping graph of cotton cloth after preparation, wherein a is a scanning graph of cotton cloth, b is an element distribution graph of C element, C is an element distribution graph of N element, d is an element distribution graph of O element, e is an element distribution graph of Si element, and f is an element distribution graph of P element.

FIG. 3 is a graph of cotton cloth plasma self-repair after preparation, wherein a is an antenna graph of cotton cloth video optical contact angle after preparation of 152.0 +/-1.8 degrees, b is a contact angle graph of cotton cloth video optical contact angle after air plasma treatment of 0 degrees, c is a contact angle graph of cotton cloth video optical contact angle after self-repair of 153.9 +/-2.7 degrees, and d is a graph of cotton cloth plasma treatment and self-repair cycle of 10 times, wherein the abscissa represents the number of times of self-repair and the ordinate represents the angle after self-repair and plasma treatment.

Fig. 4 is a scan, wherein a is a scan of an original cotton cloth and b is a scan of a cotton cloth after preparation.

Fig. 5 is a spectrum diagram, a is a spectrum diagram of an original cotton cloth, b is a spectrum diagram of a cotton cloth after preparation, wherein the abscissa represents an X-ray energy unit in KeV and the ordinate represents an X-ray count.

Fig. 6 is a scan, a is a scan of cotton after preparation, b is a scan of cotton after air plasma treatment, and c is a scan of cotton after self-repair.

FIG. 7 is an energy spectrum, a is an energy spectrum of cotton cloth after preparation, b is an energy spectrum of cotton cloth after air plasma treatment, and c is an energy spectrum of cotton cloth after self-repairing, wherein the abscissa represents the energy unit of X-ray KeV and the ordinate represents the X-ray count.

Fig. 8 is a flow chart of the present invention.

Detailed Description

The invention relates to a preparation method of a flexible substrate with a self-repairing super-hydrophobic function. The flexible substrate is pure cotton cloth, silk and polyester fiber cloth. The present invention will be described in detail with reference to various embodiments.

When a pure cotton cloth is used as the substrate:

step 1: diluting the phytic acid aqueous solution:

mixing a phytic acid aqueous solution with the concentration of 70% and ultrapure water according to the volume ratio of 1: 80-120, and uniformly mixing and stirring to obtain the diluted phytic acid aqueous solution.

TABLE 3 volume ratio of phytic acid aqueous solution to ultrapure water in each example

Step 2: preparing 3-aminopropyl group-terminated polydimethylsiloxane emulsion:

3-aminopropyl group-terminated polydimethylsiloxane and ultrapure water in a volume ratio of 3: 500-2000, and ultrasonically dispersing uniformly by using a JY92-IIDN ultrasonic cell crusher to obtain the polydimethylsiloxane emulsion for later use.

TABLE 4 volume ratio of polydimethylsiloxane to ultrapure water in each example

And step 3: preparing a flexible substrate with self-repairing super-hydrophobic function and super-hydrophobicity:

the method comprises the following steps of preparing a pure cotton fabric into a super-hydrophobic silk flexible substrate, and specifically, soaking the pure cotton fabric to be treated in a diluted phytic acid aqueous solution for 3-15 min to enable the pure cotton fabric to be completely soaked by the phytic acid aqueous solution. Adding the obtained 3-aminopropyl group-terminated polydimethylsiloxane emulsion into a phytic acid aqueous solution in which pure cotton cloth is soaked to form a mixed soaking solution, and continuously soaking the pure cotton cloth; the phytic acid aqueous solution comprises the following components: 3-aminopropyl group-terminated polydimethylsiloxane emulsion ═ 1: 1. and during soaking, stirring at a stirring speed of 500r/min for 3-15 min, and standing for 1-2 h.

And after standing, taking out the pure cotton cloth from the mixed solution, repeatedly washing the pure cotton cloth twice by using absolute ethyl alcohol with the concentration of more than 99.7 percent, and washing the pure cotton cloth twice by using distilled water.

And placing the washed pure cotton cloth in a utensil, placing the utensil in an oven, and drying the utensil at 120 ℃ for 0.5h to obtain the transparent self-healing pure cotton cloth with the super-hydrophobic function.

TABLE 5 Process parameters for preparing a superhydrophobic silk flexible substrate from a pure cotton cloth

When polyester fiber cloth is used as a substrate:

step 1: diluting the phytic acid aqueous solution:

mixing a phytic acid aqueous solution with the concentration of 70% and ultrapure water according to the volume ratio of 1: 60-130, and uniformly mixing and stirring to obtain the diluted phytic acid aqueous solution.

TABLE 6 volume ratio of phytic acid aqueous solution to ultrapure water in each example

Step 2: preparing 3-aminopropyl group-terminated polydimethylsiloxane emulsion:

3-aminopropyl group-terminated polydimethylsiloxane and ultrapure water in a volume ratio of 3: 500-2000, and ultrasonically dispersing uniformly by using a JY92-IIDN ultrasonic cell crusher to obtain the polydimethylsiloxane emulsion for later use.

TABLE 7 volume ratio of polydimethylsiloxane to ultrapure water in each example

And step 3: preparing a flexible substrate with self-repairing super-hydrophobic function and super-hydrophobicity:

the preparation method comprises the following steps of preparing polyester fiber cloth into a super-hydrophobic silk flexible substrate, and specifically, soaking the polyester fiber cloth to be treated in diluted phytic acid aqueous solution for 5-20 min to enable the polyester fiber cloth to be completely soaked by the phytic acid aqueous solution. Adding the obtained 3-aminopropyl group-terminated polydimethylsiloxane emulsion into a phytic acid aqueous solution in which a polyester fiber cloth is soaked to form a mixed soaking solution, and continuously soaking the polyester fiber cloth; the phytic acid aqueous solution comprises the following components: 3-aminopropyl group-terminated polydimethylsiloxane emulsion ═ 1: 1. and during soaking, stirring at a stirring speed of 600r/min for 1-10 min, and standing for 1-4 h.

And after standing, taking the polyester fiber cloth out of the mixed solution, repeatedly washing the polyester fiber cloth twice by using absolute ethyl alcohol with the concentration of more than 99.7 percent, and washing the polyester fiber cloth twice by using distilled water.

And (3) placing the washed polyester fiber cloth in a utensil, placing the utensil in an oven, and drying the utensil at 100 ℃ for 1h to obtain the transparent self-healing polyester fiber cloth with the super-hydrophobic function.

TABLE 8 Process parameters for preparing polyester fiber cloth into super-hydrophobic silk flexible substrate

When silk is used as the substrate:

step 1: diluting the phytic acid aqueous solution:

mixing a phytic acid aqueous solution with the concentration of 70% and ultrapure water according to the volume ratio of 1: and (3) mixing and stirring uniformly by 50-200 to obtain the diluted phytic acid aqueous solution.

TABLE 9 volume ratio of phytic acid aqueous solution to ultrapure water in each example

Step 2: preparing 3-aminopropyl group-terminated polydimethylsiloxane emulsion:

3-aminopropyl group-terminated polydimethylsiloxane and ultrapure water in a volume ratio of 3: 300-3000, and ultrasonically dispersing uniformly by using a JY92-IIDN ultrasonic cell crusher to obtain the polydimethylsiloxane emulsion for later use.

TABLE 10 volume ratio of polydimethylsiloxane to ultrapure water in each example

And step 3: preparing a flexible substrate with self-repairing super-hydrophobic function and super-hydrophobicity:

the silk is prepared into a super-hydrophobic silk flexible substrate, and specifically, the silk to be treated is placed in a diluted phytic acid aqueous solution to be soaked for 10-60 min, so that the silk is completely soaked by the phytic acid aqueous solution. Adding the obtained 3-aminopropyl group-terminated polydimethylsiloxane emulsion into a phytic acid aqueous solution soaked with silk to form a mixed soaking solution, and continuously soaking the silk; the phytic acid aqueous solution comprises the following components: 3-aminopropyl group-terminated polydimethylsiloxane emulsion ═ 1: 1. and during soaking, stirring at the stirring speed of 800r/min for 1-10 min, and standing for 1-8 h.

And after standing, taking the silk out of the mixed solution, repeatedly washing the silk twice by using absolute ethyl alcohol with the concentration of more than 99.7 percent, and washing the silk twice by using distilled water.

And placing the washed silk into a utensil, placing the utensil in an oven, and drying the utensil at 130 ℃ for 1h to obtain the transparent self-healing silk flexible substrate with the super-hydrophobic function.

TABLE 11 Process parameters for preparing a superhydrophobic silk flexible substrate from silk