A hydrophobic fabric and a method of making the same

Abstract

The application relates to the technical field of new materials, and discloses a hydrophobic fabric and a preparation method thereof.The method comprises the following steps: (1) performing ultrasonic treatment and / or low-concentration alkali liquid immersion treatment on a fabric, and obtaining a pretreated fabric after washing; (2) dissolving heptadecafluorodecyltrimethoxysilane in a solvent to obtain a heptadecafluorodecyltrimethoxysilane solution with a concentration of 0.1-10 wt%; and (3) soaking the pretreated fabric in the heptadecafluorodecyltrimethoxysilane solution, and obtaining a hydrophobic fabric after airing and drying.The method provided by the application can realize excellent hydrophobic effect by changing the chemical properties on the premise that the surface morphology of the fabric fiber does not change significantly, and finally a fiber fabric with excellent hydrophobic performance is prepared.

Description

Technical Field

[0001] This invention relates to the field of new materials technology, specifically to a hydrophobic fabric and its preparation method. Background Technology

[0002] In existing technologies, cotton fabrics are widely used in clothing and home textiles due to their natural hydrophilic properties. However, with the increasing demand for functional fabrics, hydrophobic cotton fabrics have become a research hotspot. Currently, most methods for achieving hydrophobic properties rely on altering the surface morphology of cotton fabrics, such as introducing micro / nano structures or roughening treatments. While these methods can effectively improve the hydrophobic properties of fabrics, they typically suffer from cumbersome processes and high modification costs. Therefore, methods such as impregnation are often used to reduce modification costs.

[0003] Currently, the mainstream strategy for developing hydrophobic fabric coating materials for impregnation involves impregnating hydrophobic finishing agents onto fiber materials using methods such as template methods, sol-gel hydrothermal methods, and layer-by-layer self-assembly methods. However, the low adhesion, weak mechanical strength, and limited bonding ability of hydrophobic coatings restrict the durability of their hydrophobic properties. Furthermore, the resulting hydrophobically modified fabric surface is susceptible to mechanical damage, affecting its softness and feel. Additionally, issues such as low hydrophobic durability, poor stability of hydrophobic properties, and the fabric's tendency to lose its hydrophobicity under mechanical damage persist.

[0004] Therefore, the key to solving the above problems lies in how to achieve excellent hydrophobic properties through chemical modification without significantly altering the surface morphology of cotton fabrics. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems existing in the prior art, such as the mechanical damage to the fabric surface after hydrophobic modification, the deterioration of the fabric's softness and hand feel, and the low durability and poor stability of hydrophobic properties.

[0006] To achieve the above objectives, a first aspect of the present invention provides a method for preparing a hydrophobic fabric, the method comprising the following steps:

[0007] (1) The fabric is subjected to ultrasonic treatment and / or low-concentration alkaline solution immersion treatment, and then washed to obtain the pretreated fabric.

[0008] (2) Dissolve heptadecanyltrimethoxysilane in a solvent to obtain a heptadecanyltrimethoxysilane solution with a concentration of 0.1-10 wt%.

[0009] (3) The pretreated fabric is soaked in the heptadecyltrimethoxysilane solution and dried to obtain a hydrophobic fabric.

[0010] A second aspect of the present invention provides a hydrophobic fabric prepared by the method described in the first aspect.

[0011] Compared with existing technologies, the method provided by this invention has at least the following beneficial effects:

[0012] (1) This invention pre-treats the fiber fabric and combines it with hydrophobic modification of heptadecafluorodecyltrimethoxysilane to effectively regulate the interaction between heptadecafluorodecyltrimethoxysilane and composite fiber, significantly improve the hydrophobic properties of composite fiber, and achieve excellent hydrophobic effect by changing chemical properties without significant change in the surface morphology of fabric fiber, and finally obtain fiber fabric with excellent hydrophobic properties.

[0013] Furthermore, the low-concentration alkaline solution impregnation treatment differs from the conventional alkaline etching method, which uses alkaline hydrolysis of cellulose to generate sodium cellulose salt, thereby reducing the crystallinity of cellulose and enhancing its reactivity and adsorption. The low-concentration alkaline solution impregnation treatment of this invention avoids the negative effects of high-concentration alkaline solution treatment on fibers by only partially and mildly modifying them.

[0014] (2) The heptadecafluorodecyltrimethoxysilane hydrophobic agent used in this invention has a faster hydrolysis rate and higher efficiency than commonly used ethoxylated fluorosilanes. By treating cotton fabrics with perfluorosilane, the fluorine element in the perfluorosilane is introduced into the surface of the cotton fibers through a chemical reaction. Due to the extremely high electronegativity and extremely low polarizability of the fluorine element in perfluorosilane, the hydrophobic properties of the cotton fabrics are effectively improved. At the same time, the CF bond in the perfluorosilane exhibits high chemical inertness, symmetry, and smoothness, which can significantly reduce the free energy of the cotton fiber surface, thereby inhibiting the wetting effect of water molecules on the surface. In addition, the perfluorosilane reacts with the hydroxyl groups (-OH) on the fiber surface through covalent bonding and hydrogen bonding to form a stable chemical shielding layer, which masks the hydrophilic functional groups of the fiber and further enhances the hydrophobicity. Moreover, the active silanols produced after hydrolysis can chemically bond with the hydroxyl groups on the surface of the cotton fiber fabric and the oxygen-containing groups produced by alkaline etching, and the resulting coating has more durable hydrophobicity.

[0015] (3) The method of the present invention is applicable to the soaking of most fabrics, such as nylon fabrics, vinylon fabrics, polyester fabrics, polypropylene fabrics, spandex fabrics, polyethylene fiber fabrics, and cotton fiber fabrics.

[0016] (4) The method of the present invention has a wide range of raw material sources, simple preparation process, low cost and high efficiency, and has good prospects for industrial application. Attached Figure Description

[0017] Figure 1 This is a photograph of a hydrophobic fabric loaded with water droplets prepared in a preferred embodiment of the present invention.

[0018] Figure 2This is a physical effect image of a hydrophobic fabric loaded with water droplets prepared in another preferred embodiment of the present invention;

[0019] Figure 3 This is a scanning electron microscope image of a hydrophobic fabric prepared in a preferred embodiment of the present invention;

[0020] Figure 4 This is a scanning electron microscope image of the hydrophobic fabric prepared in Comparative Example 2 of the present invention. Detailed Implementation

[0021] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0022] As mentioned above, the first aspect of the present invention provides a method for preparing a hydrophobic fabric, the method comprising the following steps:

[0023] (1) The fabric is subjected to ultrasonic treatment and / or low-concentration alkaline solution immersion treatment, and then washed to obtain the pretreated fabric.

[0024] (2) Dissolve heptadecanyltrimethoxysilane in a solvent to obtain a heptadecanyltrimethoxysilane solution with a concentration of 0.1-10 wt%.

[0025] (3) The pretreated fabric is soaked in the heptadecyltrimethoxysilane solution and dried to obtain a hydrophobic fabric.

[0026] In a preferred embodiment, in step (1), the fabric is subjected to the ultrasonic treatment and the low-concentration alkaline solution immersion treatment in sequence, and then washed to obtain a pretreated fabric. In this preferred embodiment, it is more advantageous to maintain the original morphology of the fabric while improving its hydrophobic properties.

[0027] Preferably, in step (1), the fabric is selected from at least one of recycled polyester fiber fabric, nylon fabric, vinylon fabric, polyester fabric, polypropylene fabric, spandex fabric, polyethylene fiber fabric, and cotton fiber fabric.

[0028] More preferably, the method of the present invention further includes: in step (1), the fabric is immersed in a beaker containing distilled water for ultrasonic treatment, and the conditions of the ultrasonic treatment are at least: ultrasonic power of 30-50KHz and time of 5-25min.

[0029] Preferably, in step (1), the conditions for the low-concentration alkaline solution impregnation treatment are at least: the alkaline solution concentration is 0.1-0.3 wt%, and the time is 0.1-2 h. Under this preferred condition, partial modification of cellulose can be achieved, resulting in reduced crystallinity and increased surface roughness, without causing excessive fiber depolymerization, swelling, or breakage.

[0030] According to a preferred embodiment, in step (1), the alkaline solution is selected from at least one of sodium hydroxide solution, potassium hydroxide solution and sodium carbonate solution.

[0031] Preferably, in step (1), the washing includes rinsing the fabric treated with the low-concentration alkaline solution 3-5 times with distilled water.

[0032] Preferably, in step (2), the solvent is anhydrous ethanol.

[0033] In a preferred embodiment, in step (2), the dissolution is carried out under stirring conditions, and at least the following conditions are met: temperature is 20-28°C, rotation speed is 200-1000 rpm, and time is 5-15 min.

[0034] More preferably, in step (3), the soaking is carried out by standing or stirring at a speed of less than 2000 rpm for 0.1-6 hours.

[0035] As previously stated, a second aspect of the present invention provides a hydrophobic fabric prepared by the method described in the first aspect.

[0036] The present invention will be described in detail below through examples. Unless otherwise specified, the raw materials used are all commercially available products.

[0037] Solvent: Anhydrous ethanol;

[0038] Alkaline solution: is a sodium hydroxide solution;

[0039] Fabric:

[0040] Fabric I: is a cotton fiber fabric;

[0041] Fabric II: is a recycled polyester fiber fabric.

[0042] Example 1

[0043] This embodiment illustrates that the method for preparing hydrophobic fabrics provided by the present invention is carried out according to the following steps:

[0044] (1) First, immerse the fabric (fabric I) in a beaker containing distilled water, and then sonicate it together with the beaker in an ultrasonic device for 20 minutes at an ultrasonic power of 40 kHz to obtain the first fabric; then immerse the first fabric in a low-concentration alkaline solution of 0.3 wt% for 0.25 h to obtain the second fabric; then rinse the second fabric three times with distilled water to obtain the pretreated fabric;

[0045] (2) Heptadecafluorodecyltrimethoxysilane was dissolved in a solvent for 10 min at 25°C and 600 rpm to obtain a 4 wt% heptadecafluorodecyltrimethoxysilane solution.

[0046] (3) The pretreated fabric was soaked in the heptadecyltrimethoxysilane solution at a speed of 300 rpm for 0.5 h, and then dried to obtain a hydrophobic fabric, named P1.

[0047] Figure 1 The image shows the actual effect of P1 loading water droplets.

[0048] Example 2

[0049] This embodiment illustrates that the method for preparing hydrophobic fabrics provided by the present invention is carried out according to the following steps:

[0050] (1) First, immerse the fabric (fabric II) in a beaker containing distilled water, and then sonicate it together with the beaker in an ultrasonic device for 20 minutes at an ultrasonic power of 40 kHz to obtain the first fabric; then immerse the first fabric in a low-concentration alkaline solution of 0.1 wt% for 0.25 h to obtain the second fabric; then rinse the second fabric three times with distilled water to obtain the pretreated fabric;

[0051] (2) Heptadecafluorodecyltrimethoxysilane was dissolved in a solvent for 10 min at 25°C and 800 rpm to obtain a 6 wt% heptadecafluorodecyltrimethoxysilane solution.

[0052] (3) The pretreated fabric was soaked in the heptadecyltrimethoxysilane solution at a speed of 500 rpm for 1 hour, and then dried to obtain a hydrophobic fabric, named P2.

[0053] Figure 2 The image shows the actual effect of P2 loading water droplets.

[0054] Example 3

[0055] This embodiment uses a method similar to that of Embodiment 1, except that in step (1), a low-concentration alkaline solution impregnation treatment is not performed, and the fabric is only subjected to ultrasonic treatment to obtain the pretreated fabric.

[0056] Ultimately, a hydrophobic fabric was obtained and named P3.

[0057] Example 4

[0058] This embodiment uses a method similar to that of Embodiment 1. The difference is that ultrasonic treatment is not performed in step (1). Instead, the fabric is soaked in a low-concentration alkaline solution and then washed to obtain the pretreated fabric.

[0059] Ultimately, a hydrophobic fabric was obtained, named P4.

[0060] Comparative Example 1

[0061] This comparative example was conducted using a method similar to that of Example 1, except that the operation in step (1) was omitted, and the fabric was directly soaked, specifically including:

[0062] S1. Heptadecafluorodecyltrimethoxysilane was dissolved in a solvent for 10 min at 25℃ and 600 rpm to obtain a 4 wt% heptadecafluorodecyltrimethoxysilane solution.

[0063] S2. Then, the fabric is immersed in the heptadecafluorodecyltrimethoxysilane solution at a speed of 300 rpm for 0.5 h, and after drying, a hydrophobic fabric is obtained.

[0064] Ultimately, a hydrophobic fabric was obtained, named DP1.

[0065] Comparative Example 2

[0066] This comparative example was carried out using a method similar to that of Example 1, except that in step (1), the concentration of the alkali solution in the alkali immersion treatment was 10 wt%.

[0067] Ultimately, a hydrophobic fabric was obtained, named DP2.

[0068] Comparative Example 3

[0069] This comparative example was carried out using a method similar to that of Example 1. The difference is that in step (1), ultrasonic treatment was not performed, and the fabric was only subjected to alkaline immersion treatment, and the concentration of alkaline solution in the alkaline immersion treatment was 10wt%.

[0070] Ultimately, a hydrophobic fabric was obtained, named DP3.

[0071] Comparative Example 4

[0072] This comparative example was carried out using a method similar to that of Example 1, except that in step (2), an equal mass of tridecafluorooctyltriethoxysilane was used instead of heptadecafluorodecyltrimethoxysilane for dissolution;

[0073] Ultimately, a hydrophobic fabric was obtained, named DP4.

[0074] Comparative Example 5

[0075] This comparative example was carried out using a method similar to that of Example 1, except that in step (2), an equal mass of heptadecafluorodecyltriethoxysilane was used instead of heptadecafluorodecyltrimethoxysilane for dissolution;

[0076] Ultimately, a hydrophobic fabric was obtained, named DP5.

[0077] Test Example 1

[0078] This test example applies the following tests to the hydrophobic fabrics prepared in the above examples:

[0079] Characterization of microstructure using scanning electron microscopy, among which, Figure 3 An electron microscope image of the hydrophobic fabric P1 is shown; Figure 4 Electron micrographs of the hydrophobic fabric DP2 prepared in Comparative Example 2 are shown; from Figure 3 and Figure 4 It can be seen that when the concentration of alkali solution is too high, it will cause obvious damage to the surface of the fabric.

[0080] Tensile strength was measured using a universal testing machine.

[0081] The water contact angle is measured using a water contact angle meter;

[0082] The results for tensile strength and water contact angle are shown in Table 1.

[0083] Table 1

[0084] project P1 P2 P3 P4 DP1 DP2 DP3 DP4 DP5 Tensile strength (MPa) 18.2 18.2 18.3 18.2 18.3 12.0 12.8 18.2 18.3 Water contact angle (°) 145 141 131 128 95 125 112 93 0

[0085] The results above show that the method provided by this invention achieves excellent hydrophobic effects by changing chemical properties without significantly altering the surface morphology of the fabric fibers, ultimately producing fiber fabrics with excellent hydrophobic properties. Moreover, the preparation process is simple, low-cost, and highly efficient, showing good prospects for industrial application.

[0086] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing hydrophobic fabrics, characterized in that, The method includes the following steps: (1) The fabric is subjected to ultrasonic treatment and low-concentration alkaline solution immersion treatment in sequence, and then washed to obtain pretreated fabric; the conditions of the low-concentration alkaline solution immersion treatment are at least: the alkaline solution concentration is 0.1-0.3wt%, and the time is 0.1-2h; (2) Dissolve heptadecanyltrimethoxysilane in a solvent to obtain a heptadecanyltrimethoxysilane solution with a concentration of 0.1-10 wt%; (3) The pretreated fabric is soaked in the heptadecyltrimethoxysilane solution and dried to obtain a hydrophobic fabric.

2. The method according to claim 1, characterized in that, The method further includes: in step (1), immersing the fabric in a beaker containing distilled water for the ultrasonic treatment, and the conditions of the ultrasonic treatment are at least: ultrasonic power of 30-50KHz and time of 5-25min.

3. The method according to claim 1 or 2, characterized in that, In step (1), the alkaline solution is selected from at least one of sodium hydroxide solution, potassium hydroxide solution and sodium carbonate solution.

4. The method according to claim 1 or 2, characterized in that, In step (2), the dissolution is carried out under stirring conditions, and at least the following conditions are met: temperature is 20°C, rotation speed is 200-1000 rpm, and time is 5-15 min.

5. The method according to claim 1 or 2, characterized in that, In step (3), the soaking is carried out by standing or stirring at a speed of less than 2000 rpm for 0.1-6 hours.

6. A hydrophobic fabric prepared by the method according to any one of claims 1-5.

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