阅读说明：本技术 一种超疏水浓缩液及其应用 (Super-hydrophobic concentrated solution and application thereof ) 是由 曹传祥 高彦峰 赵郁 陈长 于 2020-04-20 设计创作，主要内容包括：本发明涉及一种超疏水浓缩液及其应用,所述超疏水浓缩液为非氟硅烷偶联剂和有机酸的混合物,所述非氟硅烷偶联剂的化学通式为(R-(1))-(n)Si(R-(2)O)-(4-n),其中R-(1)为碳原子数为3～18的烷基,R-(2)为碳原子数为1～3的烷基,n=1～2。(The invention relates to an ultra-hydrophobic concentrated solution and application thereof, wherein the ultra-hydrophobic concentrated solution is a mixture of a non-fluorosilane coupling agent and an organic acid, and the chemical general formula of the non-fluorosilane coupling agent is (R) 1 ) n Si(R 2 O) 4‑n Wherein R is 1 Is alkyl with 3-18 carbon atoms, R 2 Is an alkyl group having 1 to 3 carbon atoms, and n =1 to 2.)

1. The super-hydrophobic concentrated solution is characterized in that the super-hydrophobic concentrated solution is a mixture of a non-fluorosilane coupling agent and organic acid, and the chemical general formula of the non-fluorosilane coupling agent is (R)₁)_nSi(R₂O)_4-nWherein R is₁Is alkyl with 3-18 carbon atoms, R₂Is an alkyl group having 1 to 3 carbon atoms, and n =1 to 2.

2. The superhydrophobic concentrate of claim 1, wherein the organic acid is an acid having 2-8 carbon atoms.

3. The superhydrophobic concentrate of claim 1 or 2, wherein the mass ratio of the non-fluorosilane coupling agent to the organic acid is 1: (1-5).

4. A super-hydrophobic dispersion liquid, characterized in that the super-hydrophobic concentrated liquid described in claims 1 to 3 is dispersed in an ethanol solution, and stirred and reacted for 20 to 30 minutes at a temperature of 5 to 35 ℃ to obtain the super-hydrophobic dispersion liquid.

5. The superhydrophobic dispersion of claim 4, wherein the ethanol solution has a water content of no more than 20 wt.%, preferably no more than 5 wt.%, more preferably no more than 1 wt.%; the mass ratio of the super-hydrophobic concentrated solution to the ethanol solution is 1: (5-50).

6. A super-hydrophobic coating, characterized in that the super-hydrophobic dispersion liquid of claim 4 or 5 is coated on the surface of a substrate, reacted for 0.5-1 hour at 5-35 ℃, and then dried to obtain the super-hydrophobic coating.

7. The superhydrophobic coating of claim 6, wherein the drying parameters comprise: drying for 30-60 minutes at 60-100 ℃; or drying at 5-35 ℃ for 12-24 hours.

8. A super-hydrophobic fabric is characterized in that a fabric substrate is immersed in the super-hydrophobic dispersion liquid of claim 4 or 5 to react for 0.5 to 1 hour at the temperature of 5 to 35 ℃, and then the super-hydrophobic fabric is obtained after drying;

or spraying the super-hydrophobic dispersion liquid on the surface of a fabric substrate, reacting for 0.5-1 hour at the temperature of 5-35 ℃, and drying to obtain the super-hydrophobic fabric.

9. The superhydrophobic fabric of claim 8, wherein prior to reacting, the fabric substrate is pretreated; the pretreatment comprises the following steps: soaking the fabric substrate in ethanol for ultrasonic cleaning and drying; preferably, the power of ultrasonic cleaning is 50-100W, and the time is 20-30 minutes.

10. The superhydrophobic fabric of claim 8 or 9, wherein the drying parameters comprise: drying for 30-60 minutes at 60-100 ℃; or drying at 5-35 ℃ for 12-24 hours.

Technical Field

The invention relates to an ultra-hydrophobic concentrated solution and application thereof in fabrics, in particular to a preparation method of the ultra-hydrophobic concentrated solution, the ultra-hydrophobic dispersed solution and the ultra-hydrophobic fabrics, belonging to the technical field of ultra-hydrophobic materials.

Background

The super-hydrophobic phenomenon is also one of more interesting phenomena in nature, such as 'sludge-free and non-staining' on the surface of lotus leaves. These natural phenomena have generated a great interest to researchers, and have stimulated them to start corresponding research.

The infiltration phenomenon is a phenomenon widely existing in nature, and people usually study the infiltration property of solid surface when studying the surface property of the solid. The wettability can be determined according to the size of the contact angle, when the contact angle is smaller than 90 degrees, the surface of the solid is a hydrophilic surface, and when the contact angle is smaller than 5 degrees, the surface of the solid is a super-hydrophilic surface; conversely, if the contact angle is greater than 90 °, the solid surface is a hydrophobic surface. The super-hydrophobic material is a material with a contact angle of more than 150 degrees and a rolling angle of less than 10 degrees between the surface of the material and water.

Since the advent, fabrics have been used by humans for warmth, rain, and the like. In recent years, with the continuous progress of artificial bionic technology, the heat-insulating and comfortable functions of the fabric do not meet the requirements of people any more, and the functions of water resistance, stain resistance, bacteria resistance, ultraviolet resistance and the like of the fabric are more and more brought into the vision and life of people. The super-hydrophobic fabric is widely applied to waterproof cloth, rainproof outdoor clothing, camping tents and the like due to excellent waterproof and anti-adhesion performances.

There are two main methods for preparing the super-hydrophobic material: 1) directly constructing a micro-nano rough structure on the surface of a material with low surface energy property; 2) firstly, constructing a micro-nano rough structure on the surface of a material, and then modifying the constructed rough structure by using a low-surface-energy substance. For example, patent 1 (chinese publication No. CN208812670U) discloses a novel lotus leaf effect, super-hydrophobic, bionic nano-coating structure for fabric, which makes the fabric achieve super-hydrophobic effect by preparing multiple anti-slip layers, but the preparation method is complicated; and the used water-repellent and oil-repellent layer is a fluorine-containing compound and is expensive. Patent 2 (chinese publication No. CN107880770A) discloses a method for preparing an environment-friendly multifunctional super-hydrophobic coating, which comprises mixing the prepared hydrophobic modified nano titanium dioxide with silicone resin, and coating the mixed coating on a substrate to obtain the super-hydrophobic coating, but the carbon dioxide particles introduced into the coating have an influence on the appearance of the substrate.

At present, the following preparation methods are mainly used for preparing the super-hydrophobic fabric: sol-gel method, hydrothermal method, deposition method, self-assembly method, mold method, and the like. Research on the preparation method of the super-hydrophobic fabric has been greatly advanced, but the preparation method with complex process and harsh production conditions is not enough, so that the production cost is high, and the method is not suitable for industrial production. Therefore, the research of the super-hydrophobic fabric with simple, convenient, practical, environment-friendly and durable preparation process has great significance for industrial production.

Disclosure of Invention

Aiming at the problems, the invention provides the super-hydrophobic concentrated solution and the application thereof in the fabric, the super-hydrophobic concentrated solution for the fabric is prepared by using the non-fluorosilane with low price as the raw material, and the super-hydrophobic concentrated solution is used for replacing the super-hydrophobic dispersed solution, so that the problems of large amount and difficult transportation existing in the prior storage and transportation process of the super-hydrophobic dispersed solution are effectively solved, and the preparation method of the super-hydrophobic fabric is simple and is convenient for industrial production.

In a first aspect, the present invention provides an ultrahydrophobic concentrate, which is a mixture of a non-fluorosilane coupling agent having a chemical general formula of (R) and an organic acid₁)_nSi(R₂O)_4-nWherein R is₁Is alkyl with 3-18 carbon atoms, R₂Is an alkyl group having 1 to 3 carbon atoms, and n is 1 to 2 (for example, CH)₃(CH₂)₁₅Si(OCH₃)₃、CH₃(CH₂)₁₁Si(OCH₃)₃、CH₃(CH₂)₇Si(OCH₃)₃、CH₃(CH₂)₁₅Si(OC₂H₅)₃Etc.).

In the disclosure, the non-fluorosilane coupling agent contains 2-3 methoxy groups (CH) in the molecule₃O-), ethoxy (C)₂H₅O-) or propoxy (C)₃H₇O-) and the like, which can be easily hydrolyzed in an aqueous environment to generate silicon hydroxyl, and the hydrolysis reaction can be accelerated under the promotion action of the non-fluorosilane coupling agent organic acid; the silicon hydroxyl groups formed by hydrolysis are further condensed with each other to form a linear or three-dimensional network structure, and then are combined with alkyl R with hydrophobic effect₁So that the super-hydrophobic concentrated solution has excellent super-hydrophobic performance in subsequent application. Meanwhile, under the anhydrous condition (namely, only the non-fluorosilane coupling agent and the organic acid), the organic acid can effectively inhibit the non-fluorosilaneThe self-polycondensation reaction of the coupling agent enables the non-fluorosilane coupling agent to realize long-term stability at room temperature (the non-fluorosilane coupling agent can be stored at room temperature for at least two months), and the non-fluorosilane coupling agent is convenient for early-stage transportation due to small volume. That is, no chemical reaction occurs between the non-fluorosilane coupling agent and the organic acid. In addition, the concentrated solution can be further expanded into a large amount of super-hydrophobic dispersion liquid.

Preferably, the organic acid is an acid having 2 to 8 carbon atoms, such as at least one of caprylic acid (caprylic acid), glacial acetic acid, valeric acid, oleic acid (propionic acid), caproic acid (caproic acid), and the like.

Preferably, the mass ratio of the non-fluorosilane coupling agent to the organic acid is 1: (1-5).

In a second aspect, the invention also provides a super-hydrophobic dispersion liquid, wherein the super-hydrophobic concentrated liquid is dispersed in an ethanol solution, and is stirred and reacted for 20-30 minutes at the temperature of 5-35 ℃ to obtain the super-hydrophobic dispersion liquid.

In the method, the super-hydrophobic concentrated solution is dispersed in ethanol, stirred and reacted for 20-30 minutes at the temperature of 5-35 ℃, and in the process, methoxyl (CH) in non-fluorine silane coupling agent molecules₃O-), ethoxy (C)₂H₅O-) or propoxy (C)₃H₇O-) and the like, and the partial hydrolysis is carried out to generate silicon hydroxyl, and the obtained silicon hydroxyl can be mutually condensed into a linear or three-dimensional network structure under the action of organic acid to form a compound. In the invention, the silane coupling agent is only limited to the ethanol solution, and the silane coupling agent and the ethanol solution are mutually soluble. For cost reasons, it is sufficient to use a common ethanol solution (having a water content of not more than 20% by weight). If water is directly added or excessive water is added, the problem that the hydrolysis of silane methoxyl is too fast exists, and silane and water are not mutually soluble, so that the layering phenomenon is easy to generate. The preparation process of the super-hydrophobic dispersion liquid is substantially partial methoxyl and ethoxyl (C) of the silane coupling agent₂H₅O-) or propoxy (C)₃H₇O-) and the like into a hydroxyl group.

Preferably, the mass ratio of the super-hydrophobic concentrated solution to the ethanol solution is 1: (5-50).

Preferably, the stirring mode is magnetic stirring by adopting magnetons, and the rotating speed of the magnetons is 800-1000 r/min.

In a third aspect, the invention provides a super-hydrophobic coating, wherein the super-hydrophobic dispersion is coated on the surface of a base material, and the super-hydrophobic dispersion reacts for 0.5-1 hour at the temperature of 5-35 ℃, and then is dried to obtain the super-hydrophobic coating.

In the present disclosure, the super-hydrophobic dispersion is stirred and reacted for 0.5-1 min at 5-35 ℃, and in the process, methoxyl (CH) in non-fluorine silane coupling agent molecule₃O-), ethoxy (C)₂H₅O-) or propoxy (C)₃H₇O-) and the like, and the obtained silicon hydroxyl groups can be mutually condensed into a linear or three-dimensional network structure under the promotion action of organic acid to form a compound.

Preferably, the drying parameters include: drying for 30-60 minutes at 60-100 ℃; or drying at 5-35 deg.C for 12-24 hr.

In a fourth aspect, the invention provides a super-hydrophobic fabric, a fabric substrate is immersed in the super-hydrophobic dispersion liquid to react for 0.5-1 hour at the temperature of 5-35 ℃, and then the super-hydrophobic fabric is obtained after drying; or spraying the super-hydrophobic dispersion liquid on the surface of a fabric substrate, reacting for 0.5-1 hour at the temperature of 5-35 ℃, and drying to obtain the super-hydrophobic fabric.

Preferably, the fabric substrate is pretreated prior to the reaction; the pretreatment comprises the following steps: soaking the fabric substrate in ethanol for ultrasonic cleaning and drying; preferably, the power of ultrasonic cleaning is 50-100W, and the time is 20-30 minutes.

Preferably, the drying parameters include: drying for 30-60 minutes at 60-100 ℃; or drying at 5-35 deg.C for 12-24 hr.

Has the advantages that:

according to the invention, the super-hydrophobic concentrated solution is used for replacing the super-hydrophobic dispersion solution, so that the problems of large super-hydrophobic dispersion solution amount and difficulty in transportation are effectively solved, and the preparation method of the super-hydrophobic fabric is simple and is convenient for industrial production.

Drawings

FIG. 1 is a graph of the contact angle of the fabric of example 1 before and after treatment;

FIG. 2 is a graph of the contact angle of the fabric of example 2 before and after treatment;

FIG. 3 is a graph of the contact angle of the fabric of example 3 before and after treatment;

FIG. 4 is a graph of the wet out performance of the fabric of example 3 before and after treatment;

FIG. 5 is a graph of contact and rolling angles of the treated fabric of example 3 versus the number of wash cycles;

figure 6 is a graph of contact and rolling angles versus number of rubbing cycles for the fabric of example 3 after treatment.

Detailed Description

The present invention is further illustrated by the following examples, which are to be understood as merely illustrative and not restrictive.

In the present disclosure, the general formula (R) is₁)nSi(R₂O)_4-nThe non-fluorosilane and the organic acid are mixed according to a proper proportion to obtain the super-hydrophobic concentrated solution (which can be called as concentrated solution for short). Wherein, the general formula is R₁nSi(R₂O)_4-nIn the non-fluorosilane of (2)₁Is alkyl with 3-18 carbon atoms, R₂Is alkyl with 1-3 carbon atoms, and n is 1-2. The mixing conditions include: can be uniformly mixed by magnetic stirring or manual stirring at room temperature. In the invention, organic-inorganic hybrid molecules are not formed between the non-fluorosilane coupling agent and the organic acid in the components of the super-hydrophobic concentrated solution, and only the non-fluorosilane coupling agent and the organic acid are physically mixed.

In an alternative embodiment, the organic acid is an acid having 2 to 8 carbon atoms, such as caprylic acid (n-caprylic acid), glacial acetic acid, valeric acid, caproic acid (propionic acid), caproic acid (caproic acid), and the like. Wherein the organic acid functions as: the silane coupling agent does not directly react with organic acid.

As a preferred example, the mass ratio of the non-fluorosilane coupling agent and the organic acid may be in the range of 1: 1 to 5. Within the above range, the resulting superhydrophobic property is excellent. In the present invention, the mixed solution of the non-fluorosilane coupling agent and the fatty acid is referred to as a concentrated solution, and the ratio of the two is used for analyzing and comparing the effective period of the concentrated solution, i.e., the shelf life. In the present invention, the term "shelf life" is understood to mean: the maximum storage time of the super-hydrophobic concentrated solution without obvious turbidity and flocculent precipitate can be kept at room temperature. However, in the actual "shelf life" test, due to time limitations, the maximum observed shelf life of the ultrahydrophobic concentrates obtained in the present invention was only 2 months, and it can be seen that the shelf life of the concentrates was at least 2 months or more. On one hand, if the content of the organic acid is low, the organic acid is difficult to inhibit the self-polycondensation reaction of the silane coupling agent, the shelf life of the obtained concentrated solution is shortened, and when the super-hydrophobic dispersion liquid is prepared subsequently by using the organic acid self-polycondensation reaction preparation method, a small amount of concentrated solution of the organic acid is added, and an ethanol solution is added to the concentrated solution of the organic acid, so that the pH value of the dispersion liquid is difficult to be reduced to 3-5, and the non-fluorosilane coupling agent is subjected to too fast polycondensation, and a turbid and flocculent precipitation state is generated when the non-fluorosilane coupling agent is not applied in time. On the other hand, when the organic acid is excessive, the cost is high, so the cost problem needs to be controlled by regulating and controlling the proportion of the organic acid on the premise of ensuring the long shelf life of the concentrated solution.

In one embodiment of the present invention, a solvent may be added to the superhydrophobic concentrate and mixed uniformly to prepare a superhydrophobic dispersion (which may be referred to as a dispersion for short). The solvent used may be an ethanol solution having a water content of not more than 20% by weight, preferably an ethanol solution having a water content of not more than 5% by weight, more preferably an ethanol solution having a water content of not more than 1% by weight. The reaction mechanism of the invention is that partial methoxyl groups and other groups in the non-fluorosilane coupling agent form hydroxyl groups under the hydrolysis action, a linear or three-dimensional network structure is formed through dehydration condensation among the hydroxyl groups, and long-chain alkyl plays a role in hydrophobicity. As a detailed example, the prepared super-hydrophobic concentrated solution is dispersed in the ethanol solution at room temperature, and after reaction for 20-30 minutes by magnetic stirring (the rotation speed of a magneton is 800-1000 r/min), the corresponding super-hydrophobic dispersed solution is obtained. However, if the reaction time is too long, the silane coupling agent causes irreversible excessive crosslinking, and does not exert a good hydrophobic effect. If the reaction time is too short, the reaction is incomplete, and the super-hydrophobic property is affected.

As a preferable example, the mass ratio of the superhydrophobic concentrated solution to the ethanol solution can be 1 (5-50), so that the pH of the obtained superhydrophobic dispersion can be stabilized between 3-5. Specifically, the non-fluorosilane coupling agent is hydrolyzed to form hydroxyl silane, and the speed of the polycondensation reaction of the hydroxyl silane is slowest under the condition that the pH value is 3-5, so that the preparation of a subsequent super-hydrophobic coating or super-hydrophobic fabric is facilitated. In the super-hydrophobic dispersion liquid, organic and inorganic hybrid molecules cannot be formed between the non-fluorosilane coupling agent and the organic acid combination, and only the functional groups such as the methoxy group in the non-fluorosilane coupling agent are hydrolyzed to generate hydroxyl, so that the hydroxyl is subjected to condensation polymerization to form a compound with a linear or three-dimensional network structure. The difference of the ethanol dosage in the range is only the difference of the dilution ratio of the concentrated solution, the cost problem is controlled by increasing the dilution ratio, and the super-hydrophobic performance is not obviously influenced. It should be noted that if the ethanol solution is excessive in excess of a certain dilution ratio, the pH increases so that the silane coupling agent cannot be sufficiently hydrolyzed and reacted in a weak acid environment, eventually resulting in a decrease in the superhydrophobic performance of the resulting dispersion.

Application of super hydrophobic condensed liquid.

Pretreating the fabric substrate, and ultrasonically cleaning the fabric substrate by using solvents such as acetone, ethanol, deionized water and the like to remove dust, grease and other impurities. Then drying the mixture at high temperature. The fabric base material can be cotton, terylene, wool, non-woven fabric and blended fabric thereof. Wherein, the power of ultrasonic cleaning can be 50-100W, and the time can be 20-30 minutes. In this step, the high-temperature drying may be performed at 60 ℃ to 100 ℃ for 30 minutes.

And (3) dipping the pretreated fabric substrate into the super-hydrophobic dispersion liquid, and reacting for 20-30 minutes at room temperature (5-35 ℃), so that a layer of super-hydrophobic coating is formed on the surface of the fiber in the fabric substrate. And then drying the fabric for 30 to 60 minutes at a high temperature of between 60 and 100 ℃ to obtain the super-hydrophobic fabric. The drying condition can also be room temperature, and the super-hydrophobic fabric can be obtained after drying for 12-24 hours at room temperature.

Alternatively, the super-hydrophobic dispersion is sprayed on the fabric substrate and reacted at room temperature (5 to 35 ℃) for 0.5 to 1 hour (for example, 0.5 hour), thereby forming a super-hydrophobic coating on the surface of the fibers in the fabric substrate. And then drying the fabric for 30 to 60 minutes at a high temperature of between 60 and 100 ℃ to obtain the super-hydrophobic fabric. The drying condition can also be room temperature, and the super-hydrophobic fabric can be obtained after drying for 12-24 hours at room temperature.

In the preparation process of the super-hydrophobic fabric, if the reaction time is too short, the reaction is incomplete, and the hydrophobic performance is influenced.

In another embodiment of the invention, the selected substrate can be the surface of glass, ceramic, silicon wafer, plastic and other substrates, and the super-hydrophobic coating is obtained due to the surface smoothness. The reaction temperature, the reaction time and the drying condition can be referred to the preparation process of the super-hydrophobic fabric.

The hydrophobic concentrated solution for the fabric has the advantages of simple preparation method, mild treatment conditions, high efficiency and low energy consumption, and is suitable for industrial production. The prepared super-hydrophobic fabric has good hydrophobic effect, long coating surface durability and good washability and wear resistance.

In the present disclosure, the contact angle of the resulting superhydrophobic fabric was tested using an optical contact angle measuring instrument. And (3) testing the rolling angle of the obtained super-hydrophobic fabric by adopting a Zimmermann measuring method. In the present invention, the difference in the contact angles obtained is subject to instrumental measurement errors, typically between 1 and 2 degrees.

The present invention will be described in detail by way of examples. It is also to be understood that the following examples are illustrative of the present invention and are not to be construed as limiting the scope of the invention, and that certain insubstantial modifications and adaptations of the invention by those skilled in the art may be made in light of the above teachings. The specific process parameters and the like of the following examples are also only one example of suitable ranges, i.e., those skilled in the art can select the appropriate ranges through the description herein, and are not limited to the specific values exemplified below. In the following examples and comparative examples, unless otherwise specified, an ethanol solution was used which was 99.7% by mass of absolute ethanol having a water content of 0.3% by weight.

Example 1

A preparation method and application of a super-hydrophobic concentrated solution for fabrics comprise the following steps:

1) preparing an ultra-hydrophobic concentrated solution: under the condition of room temperature, silane coupling agent CG-1631 and caprylic acid are mixed according to the mass ratio of 1: 3, mixing, and stirring at the speed of 600r/min to obtain the super-hydrophobic concentrated solution; the shelf life of the obtained super-hydrophobic concentrated solution is at least 2 months;

2) application of the super-hydrophobic concentrated solution: preparing a silane coupling agent super-hydrophobic dispersion liquid, namely dispersing the concentrated solution prepared in the step 2) in an ethanol solution at room temperature (25 ℃), wherein the mass ratio of the concentrated solution to the ethanol solution is 1: 5, stirring at 1000r/min, reacting for half an hour to obtain a silane coupling agent CG-1631 super-hydrophobic dispersion liquid with the pH value of 3.5;

3) application of the super-hydrophobic concentrated solution: pretreating a fabric substrate, ultrasonically cleaning the fabric substrate for 30 minutes by using ethanol (the ultrasonic power is 100w), and then drying the fabric substrate for 30 minutes at the temperature of between 60 and 100 ℃;

4) soaking the fabric dried in the step 3) in the super-hydrophobic dispersion liquid prepared in the step 2), reacting for half an hour at room temperature (25 ℃), and then drying for 30 minutes at 60-100 ℃ to obtain the super-hydrophobic fabric. The hydrophobic angle of the surface of the obtained super-hydrophobic fabric is 145 degrees, and the rolling angle is 8 degrees.

Example 2

A preparation method and application of a super-hydrophobic concentrated solution for fabrics comprise the following steps:

1) preparing an ultra-hydrophobic concentrated solution: under the condition of room temperature, silane coupling agent CG-1631 and caprylic acid are mixed according to the mass ratio of 1: 3, mixing, and stirring at the speed of 600r/min to obtain the super-hydrophobic concentrated solution;

2) application of the super-hydrophobic concentrated solution: preparing a silane coupling agent super-hydrophobic dispersion liquid, namely dispersing the concentrated solution prepared in the step 2) in an ethanol solution at room temperature (25 ℃), wherein the mass ratio of the concentrated solution to the ethanol solution is 1: 25, stirring at 1000r/min, reacting for half an hour to obtain a silane coupling agent CG-1631 super-hydrophobic dispersion liquid with the pH value of 3.9;

3) application of the super-hydrophobic concentrated solution: pretreating a fabric substrate, ultrasonically cleaning the fabric substrate for 30 minutes by using ethanol (the ultrasonic power is 100w), and then drying the fabric substrate for 30 minutes at the temperature of between 60 and 100 ℃;

4) soaking the fabric dried in the step 3) in the super-hydrophobic dispersion liquid prepared in the step 2), reacting for half an hour at room temperature (25 ℃), and then drying for 30 minutes at 60-100 ℃ to obtain the super-hydrophobic fabric. The surface of the obtained super-hydrophobic fabric has a hydrophobic angle of 150 degrees and a rolling angle of 10 degrees.

Example 3

A preparation method and application of a super-hydrophobic concentrated solution for fabrics comprise the following steps:

1) preparing an ultra-hydrophobic concentrated solution: under the condition of room temperature, silane coupling agent CG-1631 and caprylic acid are mixed according to the mass ratio of 1: 1, mixing, and stirring at 600r/min to obtain super-hydrophobic concentrated solution; (ii) a The shelf life of the obtained super-hydrophobic concentrated solution is at least 2 months;

2) application of the super-hydrophobic concentrated solution: preparing a silane coupling agent super-hydrophobic dispersion liquid, namely dispersing the concentrated solution prepared in the step 2) in an ethanol solution at room temperature (25 ℃), wherein the mass ratio of the concentrated solution to the ethanol solution is 1: 50, stirring at 1000r/min, reacting for half an hour to obtain the silane coupling agent CG-1631 super-hydrophobic dispersion liquid with pH of 4.1;

3) application of the super-hydrophobic concentrated solution: pretreating a fabric substrate, ultrasonically cleaning the fabric substrate for 30 minutes by using ethanol (the ultrasonic power is 100w), and then drying the fabric substrate for 30 minutes at the temperature of between 60 and 100 ℃;

4) soaking the fabric dried in the step 3) in the super-hydrophobic dispersion liquid prepared in the step 2), reacting for half an hour at room temperature (25 ℃), and then drying for 30 minutes at 60-100 ℃ to obtain the super-hydrophobic fabric. The surface of the obtained super-hydrophobic fabric has a hydrophobic angle of 150 degrees and a rolling angle of 10 degrees.

Example 4

The process for preparing a superhydrophobic fabric in this example 4 is referenced to example 2, with the only difference that: in the step 1), the mass ratio of the silane coupling agent CG-1631 to the caprylic acid is 1: 5. the shelf life of the resulting superhydrophobic concentrate is at least 2 months long. The pH of the resulting superhydrophobic dispersion was 3.8. The hydrophobic angle of the surface of the obtained super-hydrophobic fabric is 148 degrees, and the rolling angle is 9 degrees.

Example 5

The process for preparing a superhydrophobic fabric in this example 5 is referenced to example 2, with the only difference that: in the step 1), the mass ratio of the silane coupling agent CG-1631 to the caprylic acid is 1: 1. the shelf life of the resulting superhydrophobic concentrate is at least 2 months long. The pH of the resulting superhydrophobic dispersion was 3.6. The hydrophobic angle of the surface of the obtained super-hydrophobic fabric is 150 degrees, and the rolling angle is 8 degrees.

Example 6

The process for preparing a superhydrophobic fabric in this example 6 is referenced to example 2, with the only difference that: the mass ratio of the concentrated solution to the ethanol solution in the step 2) is 1: 50. the pH of the resulting superhydrophobic dispersion was 4.5. The hydrophobic angle of the surface of the obtained super-hydrophobic fabric is 145 degrees, and the rolling angle is 8 degrees.

Example 7

The process for making a superhydrophobic fabric in this example 7 was referenced to example 2, except that: in the step 1), the silane coupling agent is dodecyl trimethoxy silane, and the used acid is caprylic acid. The mass ratio of the silane coupling agent to the organic acid is 1: 1. the shelf life of the resulting superhydrophobic concentrate is at least 2 months long. The pH of the resulting superhydrophobic dispersion was 4.3. The hydrophobic angle of the surface of the obtained super-hydrophobic fabric is 145 degrees, and the rolling angle is 10 degrees.

Example 8

The process for making a superhydrophobic fabric in this example 7 was referenced to example 2, except that: in the step 1), the silane coupling agent is dodecyl trimethoxy silane, and the used acid is glacial acetic acid. The mass ratio of the silane coupling agent to the organic acid is 1: 3. the shelf life of the resulting superhydrophobic concentrate is at least 2 months long. The pH of the resulting superhydrophobic dispersion was 4.1. The hydrophobic angle of the surface of the obtained super-hydrophobic fabric is 148 degrees, and the rolling angle is 10 degrees.

Comparative example 1

The process for the preparation of "superhydrophobic fabric" in this comparative example 1 refers to example 2, with the only difference that: the mass ratio of the concentrated solution to the ethanol solution in the step 2) is 1: 60. the pH of the resulting superhydrophobic dispersion was up to 6.2. The hydrophobic angle of the surface of the obtained super-hydrophobic fabric is only 130 degrees, the rolling angle is only 18 degrees, and the super-hydrophobic fabric does not have the super-hydrophobic characteristic.

Comparative example 2

The process for the preparation of "superhydrophobic fabrics" in this comparative example 2 refers to example 2, with the only difference that: the reaction time in step 2) was short, only 5 minutes. The hydrophobic angle of the surface of the obtained super-hydrophobic fabric is only 125 degrees, the rolling angle is only 48 degrees, and the super-hydrophobic fabric does not have the super-hydrophobic characteristic.

Comparative example 3

The process for the preparation of "superhydrophobic fabrics" in this comparative example 3 refers to example 2, with the only difference that: the reaction time in step 2) is as long as 120 minutes, causing excessive crosslinking of the silane coupling agent. Flocculent crystals appear in the obtained super-hydrophobic dispersion liquid, and obvious precipitates appear on the surface of the obtained super-hydrophobic fabric.

Table 1 shows the raw material ratios and performance parameters of the superhydrophobic fabrics prepared in accordance with the present invention:

FIG. 4 is a graph of the wetting performance of the fabric in example 3 before and after treatment, and it can be seen from FIG. 4 (a) that the fabric without superhydrophobic treatment has no superhydrophobic performance, and the liquid drops spread on the fabric; while the fabric treated in example 3 is shown in fig. 4 (b), the soy sauce, cola, water and milk droplets do not infiltrate the contaminated fabric.

Fig. 5 is a graph of the relationship between the contact angle and the rolling angle of the treated fabric in example 3 and the number of washing cycles, and it can be seen from the graph that as the number of washing cycles increases, the contact angle of the hydrophobic fabric shows a tendency of increasing a small amount and then decreasing a small amount, because at a certain number of washing cycles, the fiber surface shows micro cilia due to the friction of steel balls on the fibers of the fabric surface, and as the washing continues, the silane left on the fabric is less and less, which is not beneficial to the maintenance of the hydrophobic property. As for the roll angle, the roll angle becomes gradually larger, and the hydrophobic property shows a tendency to be weakened.

Fig. 6 is a graph showing the relationship between the contact angle and the rolling angle of the treated fabric in example 3 and the number of rubbing cycles, and it can be seen that the rolling angle tends to increase with the increase of the number of rubbing cycles, and the static contact angle tends to decrease with the increase of the number of rubbing cycles. The data show that excellent rub resistance is maintained over a range, although the superhydrophobicity of the fabric surface decreases with increasing number of rubs. After 21000 times of abrasion resistance tests of the Martindale abrasion resistance instrument, the hydrophobic state is still kept, because on one hand, under the abrasion action, the fabric fibers generate micro cilia due to the abrasion action, and the micro cilia have a certain action equivalent to the construction of a micro-nano structure on the fibers, so that the hydrophobic effect is favorably generated; on the other hand, when the silane coupling agent is soaked in the solution method, besides a large amount of silane coupling agent exists on the surface of the fabric, the silane coupling agent also partially penetrates into gaps of fibers of the fabric, so that in an abrasion test, although the surface structure is partially peeled off, a large part of the silane coupling agent is still retained inside the fabric.

The invention needs to strictly control the dispersion mixing reaction time of the super-hydrophobic dispersion liquid. If the reaction time is too long, the silane coupling agent causes irreversible excessive crosslinking, and does not exert a good superhydrophobic effect. If the reaction time is too short, the reaction does not occur completely, affecting the superhydrophobic performance. According to the invention, the super-hydrophobic concentrated solution is used for replacing the super-hydrophobic dispersion solution, so that the problems of large super-hydrophobic dispersion solution amount and difficulty in transportation are effectively solved, and the preparation method of the super-hydrophobic fabric is simple and is convenient for industrial production. In addition, the storage shelf life of the super-hydrophobic concentrated solution can reach more than two months, and the super-hydrophobic fabric prepared by using the super-hydrophobic concentrated solution also has excellent washability and wear resistance.

The above-mentioned embodiments are merely descriptions of the preferred embodiments of the present invention, and do not limit the concept and scope of the present invention, and various modifications and improvements made to the technical solutions of the present invention by those skilled in the art should fall into the protection scope of the present invention without departing from the design concept of the present invention, and the technical contents of the present invention as claimed are all described in the technical claims.