Self-roughening type organic silicon super-hydrophobic finishing agent as well as preparation method and application thereof

Abstract

The invention provides a self-roughening type organosilicone super-hydrophobic finishing agent as well as a preparation method and application thereof, and belongs to the technical field of textile finishing. The preparation method comprises the following steps: mixing vinyl silicone oil with a platinum catalyst to obtain a first component; mixing vinyl silicone oil, hydrogen-containing silicone oil and an inhibitor to obtain a second component; mixing the first component and the second component with a reinforcing agent, dissolving in an organic solvent, adding water, and dispersing to obtain the finishing agent. According to the method disclosed by the invention, the finishing agent is formed by oversaturation and precipitation caused by the difference of solubility parameters of an organic silicon polymer in an organic solvent and water; when the finishing agent is used for fabric finishing, the finishing agent can be combined with heating curing treatment to promote rapid crosslinking of organic silicon liquid drops before complete diffusion on the surface of a fabric, so that construction of a self-rough surface is realized. The finishing agent can endow a fabric with an excellent hydrophobic effect, has good wear resistance, washing resistance and chemical stability, and has small influence on air permeability.

Description

Technical Field

[0001] The invention relates to the technical field of textile finishing, and in particular to a self-roughening organosilicon super-hydrophobic finishing agent and a preparation method and application thereof. Background Art

[0002] With the advancement of science and technology and the improvement of people's living standards, super-hydrophobic textiles have received more and more attention. After super-hydrophobic finishing, textiles not only have excellent super-hydrophobic properties, but also will obtain higher added value. At this stage, they have been widely used in the fields of waterproofing and antifouling, oil-water separation, self-cleaning and smart fabrics. However, the commonly used hydrophobic finishing agents on the market generally contain fluorine compounds. Although they can give fabrics a better water-repellent effect, their potential toxicity and bioaccumulation cannot be ignored. Therefore, exploring fluorine-free finishing technology and developing fluorine-free waterproof products have become a research hotspot in the direction of textile water-repellent finishing. Inspired by the special wetting phenomena of various biological surfaces in nature, there are more and more related studies on fluorine-free super-hydrophobic finishing, mainly focusing on the construction of micro / nano rough structures and the modification of low surface energy components. At present, methods such as plasma treatment, physical etching, photolithography, template-assisted deposition, etc. have been successfully applied to the construction of hydrophobic surfaces, but these methods often require complex instruments and equipment, and the process is cumbersome, the cost is high, and they are not universal and cannot be prepared on a large scale.

[0003] Organic silicon materials have the advantages of low surface energy (20-22 mN / m), high thermal stability, and excellent weather resistance, but they may not be able to give the substrate a super-hydrophobic effect when used alone. Usually, it is necessary to introduce additional inorganic nanoparticles to construct a micro / nano rough surface with low surface energy, but the wear resistance of this surface is generally poor, and during use, there is also the risk of inorganic nanoparticles peeling off and causing harm to the human body and the environment. Therefore, if a surface with a stable rough structure can be spontaneously formed based on organic silicon materials, it will show great application value in the field of fluorine-free super-hydrophobic fabric finishing.

[0004] At present, the methods for constructing self-rough surfaces based on silicone components mainly include: thermally induced phase separation, polarity induced phase separation and solvent induced phase separation. Among them, thermally induced phase separation is mainly based on the difference in solubility of polymers in the same solvent at different curing temperatures to obtain a self-rough structure, but the temperature required for this method is usually high (above 250°C), and conventional equipment is difficult to meet the process requirements. Polarity induced phase separation is mainly based on the polarity difference between polymer components, which causes phase separation to form a non-uniform structure. For example, Chinese patent CN114874697 B discloses a method for preparing a self-rough surface by polarity induced phase separation, which mainly embeds polar segments into non-polar segments, and then uses polarity differences to form phase separation during curing to obtain a self-rough surface. However, this method requires complex chemical synthesis, is time-consuming, and if fluorine-containing components are not introduced, the finished fabric cannot obtain a superhydrophobic effect. Solvent induced phase separation is based on the difference in solubility of polymers in good / bad solvents at the same temperature to form a continuous phase and a dispersed phase, and a self-rough surface is obtained after curing. Such as Chinese patent CN104790206 A discloses a kind of self-roughening porous mesh super-hydrophobic polyester fabric and preparation method thereof, mainly based on polydimethylsiloxane / polyvinyl chloride exchange induced phase separation under mixed solvent system to form self-rough surface, the full solvent system used in the method is relatively harmful to human body and environment, and polyvinyl chloride needs to be additionally introduced, and the air permeability of the fabric after finishing is not evaluated. In summary, the method for constructing a self-rough system based on phase separation is mostly to utilize the difference in solubility of polymer components under different conditions, and there are respective shortcomings, which are difficult to be applied to actual industrial production. In addition, a series of problems such as poor water washability, low stability, and large impact on air permeability existing in existing conventional super-hydrophobic finishing agents also restrict the further development of hydrophobic fabrics.

[0005] Therefore, how to prepare a fluorine-free / nanoparticle-free superhydrophobic finishing agent in an efficient and simple manner, and to achieve the finishing of superhydrophobic fabrics with wear resistance, wash resistance and chemical resistance based on simple operations is a technical difficulty that needs to be urgently solved in this field. Summary of the invention

[0006] The purpose of the present invention is to provide a self-roughening organosilicon super-hydrophobic finishing agent and a preparation method and application thereof. The self-roughening organosilicon super-hydrophobic finishing agent is fluorine-free and avoids the use of inorganic nanoparticles. It has high storage stability and requires a low curing temperature. It can give the fabric an excellent hydrophobic effect and has good wear resistance, wash resistance and chemical resistance, while having little effect on air permeability.

[0007] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions: The present invention provides a method for preparing a self-roughening organosilicon super-hydrophobic finishing agent, comprising the following steps: Mixing vinyl silicone oil with a platinum catalyst to obtain a first component; Mixing vinyl silicone oil, hydrogen silicone oil and inhibitor to obtain a second component; The first component, the second component and the reinforcing agent are mixed to perform an addition reaction, the obtained silicone polymer component is dissolved in an organic solvent, and water is added to obtain a self-roughening silicone super hydrophobic finishing agent through dispersion; The polarity of the organic solvent is less than that of water.

[0008] Preferably, the vinyl silicone oil comprises vinyl-terminated polydimethylsiloxane and / or vinyl-terminated polymethylvinylsiloxane; and the viscosity of the vinyl silicone oil is 1000-100000 mPa·s.

[0009] Preferably, the mass ratio of the vinyl silicone oil to the platinum catalyst in the first component is 100.5-110.5:1.

[0010] Preferably, the hydrogen content of the hydrogen-containing silicone oil is 1.2-1.6%; the hydrogen-containing silicone oil is one or both of end-chain hydrogen-containing silicone oil and side-chain hydrogen-containing silicone oil; the inhibitor includes 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane, 1-ethynyl-1-cyclohexanol, 2-methyl-3-butyn-2-ol or 3,7,11-trimethyldodecyn-3-ol.

[0011] Preferably, the mass ratio of vinyl silicone oil, hydrogen-containing silicone oil and inhibitor in the second component is 10.5-13.5:6-8:1.

[0012] Preferably, the reinforcing agent comprises vinyl MQ silicone resin; the M / Q ratio of the vinyl MQ silicone resin is 0.5 to 1.5; The vinyl MQ silicone resin includes methyl vinyl MQ silicone resin and / or vinyl phenyl MQ silicone resin; The mass ratio of the first component, the second component and the reinforcing agent is 1:1:0.25-5.3.

[0013] Preferably, the organic solvent includes one or more of tetrahydrofuran, ethyl acetate, n-hexane, dichloromethane and chloroform.

[0014] Preferably, the mass ratio of water to organic solvent is 1-4:1; the ratio of the mass of the silicone polymer component to the total mass of organic solvent and water is 1-1.5:100; the stirring speed of the dispersion is 2000-10000 r / min, and the dispersion time is 5-30 min.

[0015] The present invention provides application of a self-roughening organosilicon super-hydrophobic finishing agent prepared by the preparation method described in the above technical scheme in waterproof finishing of fabrics.

[0016] Preferably, the self-roughening organosilicon super-hydrophobic finishing agent is used for fabric finishing by spraying or dipping, and then cured by heating to form a self-roughening structure on the fabric surface.

[0017] The invention provides a method for preparing a self-roughening organosilicon super-hydrophobic finishing agent, comprising mixing vinyl silicone oil with a platinum catalyst to obtain a first component; mixing vinyl silicone oil, hydrogen-containing silicone oil and an inhibitor to obtain a second component; mixing the first and second components with a reinforcing agent, dissolving them in an organic solvent, adding water, and dispersing to obtain a finishing agent. The obtained finishing agent is used for fabric finishing, and after heating and curing, a self-roughening structure with low surface energy can be formed on the surface of the fabric.

[0018] The method of the present invention first synthesizes a silicone polymer component, and then utilizes the difference in solubility parameters of the silicone polymer in organic solvents of different polarities and water to cause supersaturation and precipitation, thereby forming a finishing agent. When the finishing agent is used for fabric finishing, it can be combined with a heating and curing treatment to promote the rapid cross-linking of silicone droplets before they are completely diffused on the fabric surface, so as to achieve the construction of a self-rough surface. The finishing agent is fluorine-free and avoids the use of inorganic nanoparticles. It has high storage stability and requires a low curing temperature. It can give the fabric an excellent hydrophobic effect (the water contact angle can reach up to 158°) and has good wear resistance, washability and chemical resistance, while having little effect on air permeability.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention can realize the construction of a self-rough structure on the surface of the fabric only based on the low surface energy organic silicon material, without the need to introduce additional inorganic nanoparticles, thus avoiding the harm to the human body and the environment caused by easy peeling of inorganic nanoparticles.

[0020] Different from the method of using polydimethylsiloxane / polyvinyl chloride to perform phase separation in a mixed solvent system in the prior art, the present invention only constructs a water-rich dispersion system based on organic silicon materials and realizes the formation of a self-roughening surface through rapid heating treatment (promoting cross-linking and curing), which effectively reduces the use of volatile solvents. At the same time, the finishing agent has excellent storage stability (no sedimentation after storage at room temperature for 3 months); compared with the high baking temperature (≥130°C) required for traditional hydrophobic finishing agents for fabric finishing, the self-roughening finishing agent provided by the present invention can achieve cross-linking and curing at a relatively low temperature (80°C), with low energy consumption, and can give the fabric a super-hydrophobic effect (the water contact angle can reach up to 158°, and the water-wetting level can reach level 5), with little effect on air permeability.

[0021] Furthermore, due to the introduction of vinyl MQ silicone resin, it can be used as a reinforcing agent to increase the degree of cross-linking of the system, and can effectively improve the mechanical strength of the self-roughening organic silicone superhydrophobic finishing agent and the fabric, thereby showing excellent wear resistance, wash resistance and chemical resistance.

[0022] The self-roughening organosilicon super-hydrophobic finishing agent provided by the present invention does not contain fluorine, thereby avoiding its potential toxicity and bioaccumulation; the present invention does not require complex chemical synthesis, has a simple preparation process, mild reaction conditions, strong operability, high practical value, and is suitable for large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a morphology picture of the self-roughening organosilicon super hydrophobic finishing agent prepared in Example 1; Figure 2 The self-roughening type organosilicon super hydrophobic finishing agent prepared in Example 1 is taken before and after storage; Figure 3 The scanning electron microscope images of the aramid fabric before and after finishing with the self-roughening organosilicon super-hydrophobic finishing agent in Example 1; Figure 4 The hydrophobic effect of different droplets on aramid fabric treated with self-rough silicone super hydrophobic finishing agent; Figure 5 The contact angles of the aramid fabric after treatment in Example 1 before and after the washing resistance, abrasion resistance and chemical resistance stability tests. DETAILED DESCRIPTION

[0024] In the present invention, unless otherwise specified, the required raw materials or reagents are commercially available products well known to those skilled in the art.

[0025] The present invention provides a method for preparing a self-roughening organosilicon super-hydrophobic finishing agent, comprising the following steps: Mixing vinyl silicone oil with a platinum catalyst to obtain a first component; Mixing vinyl silicone oil, hydrogen silicone oil and inhibitor to obtain a second component; The first component, the second component and the reinforcing agent are mixed to perform an addition reaction, the obtained silicone polymer component is dissolved in an organic solvent, and water is added to obtain a self-roughening silicone super hydrophobic finishing agent through dispersion; The polarity of the organic solvent is less than that of water.

[0026] In the present invention, the vinyl silicone oil preferably includes vinyl-terminated polydimethylsiloxane and / or vinyl-terminated polymethylvinylsiloxane; the viscosity of the vinyl silicone oil is preferably 1000-100000 mPa·s. When the vinyl silicone oil is any of the above two types, the present invention has no special restrictions on the ratio of different types of vinyl silicone oils, and any ratio is acceptable.

[0027] The present invention has no particular limitation on the source and specific type of the platinum catalyst, and any commercially available product known in the art may be used. In an embodiment of the present invention, the platinum catalyst is specifically a Custer platinum catalyst (5000ppm, Dongguan Zhongxin Silicone Material Co., Ltd.).

[0028] In the present invention, the mass ratio of the vinyl silicone oil to the platinum catalyst in the first component is preferably 100.5-110.5:1, more preferably 100.5-105.5:1.

[0029] The present invention has no particular limitation on the conditions for mixing the vinyl silicone oil and the platinum catalyst. The materials can be uniformly mixed according to a process well known in the art. In the embodiment of the present invention, the mixing is carried out under mechanical stirring at a speed of 1200 r / min for 15 min.

[0030] In the present invention, the hydrogen content of the hydrogen-containing silicone oil is preferably 1.2-1.6%; the hydrogen-containing silicone oil is preferably one or two of end-chain hydrogen-containing silicone oil and side-chain hydrogen-containing silicone oil; when the hydrogen-containing silicone oil is the above two, the present invention has no special limitation on the ratio of different types of hydrogen-containing silicone oils, and any ratio is acceptable.

[0031] In the present invention, the inhibitor preferably includes 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane (CAS No. 2554-06-5), 1-ethynyl-1-cyclohexanol, 2-methyl-3-butyn-2-ol or 3,7,11-trimethyldodecyn-3-ol.

[0032] In the present invention, the mass ratio of the vinyl silicone oil, the hydrogen-containing silicone oil and the inhibitor in the second component is preferably 10.5-13.5:6-8:1, and more preferably 11.5-12.5:6-8:1.

[0033] The present invention has no particular limitation on the mixing conditions of the vinyl silicone oil, hydrogenated silicone oil and inhibitor, and the materials can be uniformly mixed according to a process well known in the art; in the embodiment of the present invention, the mechanical stirring is carried out at a speed of 1200 r / min for 15 min.

[0034] In the present invention, the reinforcing agent preferably includes vinyl MQ silicone resin; the vinyl MQ silicone resin preferably includes methyl vinyl MQ silicone resin and / or vinyl phenyl MQ silicone resin; the M / Q ratio of the vinyl MQ silicone resin is 0.5 to 1.5. When the vinyl MQ silicone resin is any of the above two types, the present invention has no special restrictions on the ratio of different types of vinyl MQ silicone resins, and any ratio is acceptable.

[0035] In the present invention, the mass ratio of the first component, the second component and the reinforcing agent is preferably 1:1:0.25-5.3, more preferably 1:1:0.6-5.3, and further preferably 1:1:0.86-2.

[0036] In the present invention, vinyl silicone oil reacts with hydrogen-containing silicone oil under the action of a catalyst, and the second component can be stably stored due to the presence of an inhibitor, and the first component (containing a catalyst) and the second component are mixed to undergo a polymerization reaction to form a polymer; at the same time, the reinforcing agent vinyl MQ silicone resin and the vinyl silicone oil both contain double bonds, which will undergo an addition reaction with the silicon-hydrogen bond in the hydrogen-containing silicone oil. In the present invention, the introduction of a reinforcing agent into the organosilicon polymer can increase the stability of the self-roughening structure, thereby making the performance of the finishing agent better.

[0037] In the present invention, the organic solvent preferably includes one or more of tetrahydrofuran, ethyl acetate, n-hexane, dichloromethane and chloroform; when the organic solvent is two or more of the above, the present invention has no special limitation on the ratio of different types of organic solvents, and any ratio is acceptable.

[0038] In the present invention, the mass ratio of water to organic solvent is preferably 1-4:1, more preferably 2.33-4:1; the ratio of the mass of the silicone polymer component to the total mass of organic solvent and water is preferably 1-1.5:100, more preferably 1.03-1.43:100, further preferably 1.03-1.33:100.

[0039] The present invention has no particular limitation on the conditions for mixing the first component, the second component and the reinforcing agent. The materials can be uniformly mixed according to a process well known in the art. In the embodiment of the present invention, the mixing is specifically carried out at 1200 r / min for 30 seconds.

[0040] In the present invention, the mixture obtained by mixing the first component, the second component and the reinforcing agent is preferably dissolved in an organic solvent, and water is added to disperse. In the present invention, the stirring speed of the dispersion is preferably 2000-10000 r / min, more preferably 4000-5000 r / min, and the dispersion time is preferably 5-30 min, more preferably 8-10 min.

[0041] The present invention provides application of a self-roughening organosilicon super-hydrophobic finishing agent prepared by the preparation method described in the above technical scheme in waterproof finishing of fabrics.

[0042] In the present invention, the self-roughening organosilicon super-hydrophobic finishing agent is preferably used for fabric finishing by spraying or dipping, and then cured by heating to form a self-roughening structure on the fabric surface.

[0043] The present invention has no particular limitation on the specific composition of the spraying or dipping. The self-roughening organic silicon super hydrophobic finishing agent can be directly used for fabric finishing in a spraying or dipping manner well known in the art.

[0044] In the present invention, the number of heating and curing preferably corresponds to the number of spraying or dipping, and heating and curing are performed after each spraying or dipping. The temperature of each heating and curing is independently preferably 60-90°C, more preferably 70-80°C, and the time is preferably 30 minutes. After all spraying or dipping is completed, the time for continuing heating and curing is preferably 2 hours. The present invention promotes the volatilization of solvents and water by heating to achieve cross-linking and curing of the self-roughening organosilicon finishing agent.

[0045] In the present invention, the fabric is preferably pure cotton, cotton-polyester, aramid, polyimide or a blended fabric thereof. The present invention has no particular limitation on the specific specifications and sources of the fabric, and any corresponding fabric known in the art can be used.

[0046] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0047] In the following examples, the vinyl-terminated polydimethylsiloxane is derived from Zhejiang Xin'an Chemical Industry Group Co., Ltd. (XHG-206), the platinum catalyst is a Custer platinum catalyst (5000 ppm, Dongguan Zhongxin Silicone Material Co., Ltd.); the hydrogen-containing silicone oil is derived from Zhejiang Xin'an Chemical Industry Group Co., Ltd. (XHG-202), the inhibitor (2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane) is derived from Shanghai Aladdin Biochemical Technology Co., Ltd. (≥97%), and the methyl vinyl MQ silicone resin is derived from Zhejiang Xin'an Chemical Industry Group Co., Ltd. (Wynca-5325); and the aramid fabric is derived from Beijing Bangwei Putai Protective Textile Co., Ltd. (M53610A).

[0048] Example 1 The method for preparing the self-roughening organosilicon super-hydrophobic finishing agent provided in this embodiment comprises the following steps: At room temperature, 50.25 g of vinyl-terminated polydimethylsiloxane (viscosity 1000 mPa·s) and 0.5 g of platinum catalyst (5000 ppm) were weighed into a beaker, and mechanically stirred at a speed of 1200 r / min for 15 min until the mixture was uniformly mixed to obtain a first component; 37.75 g of vinyl-terminated polydimethylsiloxane (viscosity of 100,000 mPa·s), 18 g of hydrogenated silicone oil (hydrogen content of 1.6%) and 3 g of inhibitor (2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane) were placed in a beaker and stirred at a speed of 1200 r / min for 15 min to obtain a second component; Construction of water-rich system: weigh 10 g of the first component and the second component in a mass ratio of 1:1, add 3.3 g of methyl vinyl MQ silicone resin (M / Q ratio is 0.71) and stir at 1200 r / min for 30 seconds, and dissolve the resulting mixture in 300 g of tetrahydrofuran; take another 700 g of deionized water and inject it into the above mixture under high-speed stirring conditions (4000 r / min), disperse for 10 minutes, and obtain a self-roughening type silicone super hydrophobic finishing agent; The self-roughening organic silicon super hydrophobic finishing agent prepared in Example 1 was sprayed onto the aramid fabric. The conditions for each spraying were as follows: spraying pressure 0.1 bar, distance from the spray gun to the fabric 10 cm, spraying amount 0.2 mL / cm 2 , sprayed 4 times in total, cured at 80℃ for 30min immediately after each spraying, and the last drying time was extended to 2h to obtain the finished fabric.

[0049] Example 2 The method for preparing the self-roughening organosilicon super-hydrophobic finishing agent provided in this embodiment specifically comprises the following steps: The preparation methods of the first component and the second component are the same as those of Example 1; 10 g of the first component and the second component were weighed in a mass ratio of 1:1, and then 1.3 g of methyl vinyl MQ silicone resin (M / Q ratio is 0.71) was added and stirred at 1200 r / min for 30 seconds, and the resulting mixture was dissolved in 300 g of tetrahydrofuran; 700 g of deionized water was injected into the above mixture under high-speed stirring conditions (4000 r / min), and dispersed for 10 minutes to obtain a self-roughening type organic silicon super hydrophobic finishing agent; The self-roughening organic silicon super hydrophobic finishing agent is sprayed onto the aramid fabric, and the spraying method is the same as that in Example 1.

[0050] Example 3 The method for preparing the self-roughening organosilicon super-hydrophobic finishing agent provided in this embodiment specifically comprises the following steps: The preparation methods of the first component and the second component are the same as those of Example 1; 10 g of the first component and the second component were weighed in a mass ratio of 1:1, and then 3.3 g of methyl vinyl MQ silicone resin (MQ ratio is 0.71) was added and stirred at 1200 r / min for 30 seconds, and further dissolved in 500 g of tetrahydrofuran; 500 g of deionized water was injected into the above mixture under high-speed stirring conditions (4000 r / min), and dispersed for 10 minutes to obtain a self-roughening type organic silicon super hydrophobic finishing agent; The self-roughening organic silicon super hydrophobic finishing agent is sprayed onto the aramid fabric, and the spraying method is the same as that in Example 1.

[0051] Example 4 The method for preparing the self-roughening organosilicon super-hydrophobic finishing agent provided in this embodiment specifically comprises the following steps: The preparation methods of the first component and the second component and the construction method of the water-rich system are the same as in Example 1; The self-roughening organosilicon super-hydrophobic finishing agent was sprayed onto the aramid fabric according to the spraying conditions of Example 1 for a total of 4 times. After each spraying, the fabric was immediately cured at 60° C. for 30 minutes. The last drying time was extended to 2 hours to obtain the finished fabric.

[0052] Example 5 The method for preparing the self-roughening organosilicon super-hydrophobic finishing agent provided in this embodiment specifically comprises the following steps: The preparation methods of the first component and the second component and the construction method of the water-rich system are the same as in Example 1; The self-roughening organosilicon super-hydrophobic finishing agent was sprayed onto the aramid fabric according to the spraying conditions of Example 1 for a total of 6 times. After each spraying, the fabric was immediately cured at 80° C. for 30 minutes. The last drying time was extended to 2 hours to obtain the finished fabric.

[0053] Example 6 The method for preparing the self-roughening organosilicon super-hydrophobic finishing agent provided in this embodiment specifically comprises the following steps: The preparation methods of the first component and the second component are the same as those of Example 1; 10 g of the first component and the second component were weighed in a mass ratio of 1:1, and then 4.3 g of methyl vinyl MQ silicone resin (M / Q ratio is 1.0) was added and stirred at 1200 r / min for 30 seconds, and the resulting mixture was dissolved in 300 g of ethyl acetate; 700 g of deionized water was injected into the above mixture under high-speed stirring conditions (5000 r / min), and dispersed for 8 minutes to obtain a self-roughening type organic silicon super hydrophobic finishing agent; The self-roughening organic silicon super hydrophobic finishing agent is sprayed onto the aramid fabric, and the spraying method is the same as that in Example 1.

[0054] Example 7 The method for preparing the self-roughening organosilicon super-hydrophobic finishing agent provided in this embodiment specifically comprises the following steps: At room temperature, 55.25 g of vinyl-terminated polydimethylsiloxane (3000 mPa·s) and 0.5 g of platinum catalyst (5000 ppm) were weighed into a beaker, and mechanically stirred at a speed of 1200 r / min for 15 min until the mixture was uniformly mixed to obtain a first component; 32.75 g of vinyl-terminated polydimethylsiloxane (50000 mPa·s), 24 g of hydrogenated silicone oil (hydrogen content 1.2%) and 3 g of inhibitor (2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane) were placed in a beaker, and stirred at a speed of 1200 r / min for 15 min until the mixture was uniformly mixed, to obtain a second component; The method for constructing the water-rich system is the same as in Example 1; The aramid fabric was immersed in the self-roughening organosilicon super hydrophobic finishing agent in Example 7 for 30 min. The drying temperature was 80° C. and the fabric was first dried for 2 h and then dried for another 2 h.

[0055] Characterization and testing 1) The morphology of the self-roughening organosilicon super hydrophobic finishing agent prepared in Example 1 was observed by metallographic polarizing microscope. Figure 1 It can be seen that the dispersed droplets are uniformly spherical and have no agglomeration phenomenon.

[0056] 2) Figure 2 The self-roughening type organic silicon super hydrophobic finishing agent prepared in Example 1 is a real photo before and after storage. Figure 2 It can be seen that after 3 months of storage at room temperature, the appearance of the self-roughened organosilicon super-hydrophobic finishing agent is almost consistent with its initial state, with no sedimentation, indicating that it has good storage stability.

[0057] 3) Figure 3 The scanning electron microscope images of the aramid fabric before and after finishing with the self-roughening organic silicon super hydrophobic finishing agent in Example 1 are shown in FIG. Figure 3 It can be found that compared with the unfinished aramid fabric, the fiber surface of the finished aramid fabric has an irregular rough structure, indicating that the silicone finishing agent has been successfully loaded on the fabric surface. Combined with the low surface energy characteristics of the silicone component and the construction of the self-rough surface, the finished aramid fabric will show a good superhydrophobic effect.

[0058] 4) Figure 4 The hydrophobic effect diagram of different droplets on aramid fabric treated with a self-rough type organic silicon super hydrophobic finishing agent; wherein, the tea is white hair silver needle tea, the juice is commercially available Huiyuan orange juice, the milk is commercially available Mengniu pure milk, the coffee is commercially available Nestle coffee brewing liquid, the cola is commercially available Coca-Cola, and the water is tap water; Figure 4 It can be seen that various droplets can stably remain on the aramid fabric treated with the self-roughening silicone superhydrophobic finishing agent without spreading, indicating that the hydrophobic properties of the finished fabric are excellent.

[0059] 5) Perform performance tests on the finished fabrics: The contact angle of the finished fabric was tested according to GB / T 42694-2023; the moisture resistance of the finished fabric was tested according to GB / T 4745-2012; the finished fabric was washed according to GB / T 8629-2017; the air permeability of the finished fabric was tested according to GB / T 5453-1997.

[0060] The wear resistance of the finished aramid fabric was tested. The test conditions were as follows: the sample was placed on 800-mesh sandpaper, a 100g weight was placed on the upper surface of the fabric, and then the fabric was moved 15cm horizontally along the sandpaper at a speed of 7.5cm / s, and then moved to the starting point in the opposite direction, which was recorded as one cycle.

[0061] The chemical stability of the finished aramid fabric was tested under the following test conditions: the samples were immersed in acid (HCl, pH=1), alkali (NaOH, pH=12), and salt (NaCl, pH=7) solutions for 24 h.

[0062] Figure 5 The contact angles of the aramid fabric after treatment in Example 1 before and after the washing resistance, abrasion resistance and chemical resistance stability tests.

[0063] The test results show that: The water contact angle of the aramid fabric after treatment in Example 1 is 158° ( Figure 5 ), the surface water level is level 5; after 10 washes, the water contact angle is 151°, and the surface water level is level 4~5, indicating that it has good superhydrophobic effect, anti-wetting and washing resistance; the air permeability of aramid fabric before and after finishing is 435mm / s and 394mm / s respectively, indicating that the self-roughening silicone finishing agent has little effect on the air permeability of the fabric.

[0064] The water contact angle of the finished fabric sample in Example 1 after 400 friction cycles is 152°, indicating that it has good wear resistance.

[0065] Even in a harsh acid or alkaline environment, the finished fabric sample in Example 1 still exhibits a relatively high water contact angle (acid -150°, alkali -152°, salt -153°), indicating that it has excellent chemical resistance and stability.

[0066] Compared with Example 1, the aramid fabric in Example 2 still has a super-hydrophobic effect after finishing (water contact angle is 156°), but after 10 washes, the water contact angle drops to 125°, and the surface water level drops to level 3; in addition, after the wear resistance and chemical stability tests, the water contact angle of the sample also drops significantly (the water contact angle is less than 140°). This is mainly because the methyl vinyl MQ silicone resin can be used as a reinforcing agent, which can participate in the addition reaction between the terminal vinyl polydimethylsiloxane and the hydrogen-containing silicone oil to increase the degree of crosslinking, thereby effectively improving the mechanical firmness of the self-roughening type silicone finishing agent. However, the amount of methyl vinyl MQ silicone resin introduced in Example 2 is relatively low, and the degree of crosslinking of the system is insufficient, resulting in decreased wear resistance and chemical stability.

[0067] Although the aramid fabric after finishing in Example 3 still has a superhydrophobic effect (water contact angle of 151°), it is lower than that in Example 1. This is because one of the construction mechanisms of the self-roughening system is due to the difference in solubility parameters of polysiloxane segments in water and non-polar solvents. When only non-polar solvents are used as dispersants, the organosilicon component can be well dispersed; and with the addition of deionized water, the solubility of the solution to the organosilicon component decreases, and it precipitates due to supersaturation, and finally disperses to form a finishing agent dispersion. The mass ratio of deionized water to tetrahydrofuran in Example 1 is 7:3, while the mass ratio of deionized water to tetrahydrofuran in Example 3 is reduced to 1:1. Since the proportion of deionized water in Example 3 is relatively small and the degree of supersaturation is insufficient, the number of droplets in the dispersion is small and the particle size is small, which is not conducive to the formation of a rough surface, thereby affecting the superhydrophobic performance.

[0068] Although the aramid fabric after finishing in Example 4 still has a high hydrophobic effect (water contact angle of 145°, surface water level of 4), it is significantly reduced compared with Example 1. This is because the construction of the self-roughening system is due to the formation of micro / nano droplets in the water-rich system on the one hand, and on the other hand, it is necessary to promote the rapid cross-linking of silicone droplets at a relatively high temperature, so that the droplets are cured on the fiber surface before they are completely diffused to form a self-roughening structure. Compared with Example 1, the curing temperature of Example 4 is relatively low (60°C), which is not conducive to the rapid cross-linking and curing of the droplets, thereby affecting the construction of the rough surface and reducing the hydrophobic effect.

[0069] In Example 5, the water contact angle of the aramid fabric after treatment was 157°, and the surface water level was 5. After washing 10 times, the water contact angle was 153°, and the surface water level was 4-5. This was mainly due to the increase in the number of spraying times, which improved the washing resistance.

[0070] In Example 6, the water contact angle of the aramid fabric after treatment was 158°, and the surface water wetting grade was 5. After washing 10 times, the water contact angle was 152°, and the surface water wetting grade was 4-5, which was similar to the test results of Example 1.

[0071] In Example 7, the water contact angle of the aramid fabric after finishing was 155°, and the surface water level was 5. After washing 10 times, the water contact angle was 150°, and the surface water level was 4-5, indicating that the finishing method of immersion can also give the fabric a good hydrophobic effect.

[0072] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a self-roughening organosilicon super-hydrophobic finishing agent, characterized in that: The following steps are involved: Mixing vinyl silicone oil with a platinum catalyst to obtain a first component; Mixing vinyl silicone oil, hydrogen silicone oil and inhibitor to obtain a second component; The first component, the second component and the reinforcing agent are mixed to perform an addition reaction, the obtained silicone polymer component is dissolved in an organic solvent, and water is added to obtain a self-roughening silicone super hydrophobic finishing agent through dispersion; The polarity of the organic solvent is less than that of water.

2. The preparation method according to claim 1, characterized in that: The vinyl silicone oil comprises vinyl-terminated polydimethylsiloxane and / or vinyl-terminated polymethylvinylsiloxane; the viscosity of the vinyl silicone oil is 1000-100000 mPa·s.

3. The preparation method according to claim 1, characterized in that: The mass ratio of the vinyl silicone oil to the platinum catalyst in the first component is 100.5-110.5:

1.

4. The preparation method according to claim 1, characterized in that: The hydrogen content of the hydrogen-containing silicone oil is 1.2-1.6%; the hydrogen-containing silicone oil is one or both of end-chain hydrogen-containing silicone oil and side-chain hydrogen-containing silicone oil; the inhibitor includes 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane, 1-ethynyl-1-cyclohexanol, 2-methyl-3-butyn-2-ol or 3,7,11-trimethyldodecyn-3-ol.

5. The preparation method according to claim 1 or 4, characterized in that: The mass ratio of vinyl silicone oil, hydrogen-containing silicone oil and inhibitor in the second component is 10.5-13.5:6-8:

1.

6. The preparation method according to claim 5, characterized in that: The reinforcing agent includes vinyl MQ silicone resin; the M / Q ratio of the vinyl MQ silicone resin is 0.5 to 1.5; The vinyl MQ silicone resin includes methyl vinyl MQ silicone resin and / or vinyl phenyl MQ silicone resin; The mass ratio of the first component, the second component and the reinforcing agent is 1:1:0.25-5.

3.

7. The preparation method according to claim 1, characterized in that: The organic solvent includes one or more of tetrahydrofuran, ethyl acetate, n-hexane, dichloromethane and chloroform.

8. The preparation method according to claim 1 or 7, characterized in that: The mass ratio of water to organic solvent is 1-4:1; the ratio of the mass of the silicone polymer component to the total mass of organic solvent and water is 1-1.5:100; the stirring speed of the dispersion is 2000-10000 r / min, and the dispersion time is 5-30 min.

9. A self-roughening organosilicon super-hydrophobic finishing agent prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the self-roughening organosilicon super hydrophobic finishing agent according to claim 9 in fabric waterproof finishing, wherein the self-roughening organosilicon super hydrophobic finishing agent is used for fabric finishing by spraying or dipping, and then cured by heating to form a self-roughening structure on the fabric surface.

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