阅读说明：本技术 一种水性无氟稳定超疏水织物的制备方法 (Preparation method of water-based fluorine-free stable super-hydrophobic fabric ) 是由 张俊平 田宁 刘克静 曹晓君 李步成 李凌霄 杨燕飞 于 2020-04-24 设计创作，主要内容包括：本发明公开了一种水性无氟稳定超疏水织物的制备方法,是先以水为溶剂,无机酸为催化剂,烷基硅烷和硅烷偶联剂共水解缩合反应,制得具有Janus分子结构的有机硅烷聚合物悬浮液；再将有机硅烷聚合物悬浮液稀释浸泡清洗过的织物,压滤去除多余液体后在120~180℃下固化处理,即得水性无氟稳定超疏水织物。本发明利用烷基硅烷和硅烷偶联剂协同效应制得具有Janus分子结构的有机硅烷聚合物水性,该有机硅烷聚合物同时含有疏水链和偶联链,疏水链可赋予织物超疏水性,偶联链可将有机硅烷聚合物牢固键合于织物表面,从而赋予超疏水织物优异的超疏热水性、防水性和稳定性,且制备工艺绿色环保、简单、成本低廉,可进行规模化生产。(The invention discloses a preparation method of an aqueous fluorine-free stable super-hydrophobic fabric, which comprises the steps of firstly, taking water as a solvent, taking inorganic acid as a catalyst, and carrying out cohydrolysis condensation reaction on alkyl silane and a silane coupling agent to prepare an organosilane polymer suspension with a Janus molecular structure; and diluting the organosilane polymer suspension, soaking the cleaned fabric, performing filter pressing to remove redundant liquid, and curing at 120-180 ℃ to obtain the water-based fluorine-free stable super-hydrophobic fabric. According to the invention, the organosilane polymer with the Janus molecular structure is prepared by utilizing the synergistic effect of the alkyl silane and the silane coupling agent, the organosilane polymer simultaneously contains a hydrophobic chain and a coupling chain, the hydrophobic chain can endow the fabric with super-hydrophobicity, and the coupling chain can firmly bond the organosilane polymer on the surface of the fabric, so that the super-hydrophobic fabric is endowed with excellent super-hydrophobic hot-water-based property, water resistance and stability, and the preparation process is green, environment-friendly, simple and low in cost, and can be used for large-scale production.)

1. A preparation method of an aqueous fluorine-free stable super-hydrophobic fabric comprises the following process steps:

(1) preparation of organosilane polymer suspension of Janus molecular structure: using water as a solvent and inorganic acid as a catalyst, and carrying out cohydrolysis condensation reaction on alkyl silane and a silane coupling agent to prepare an organosilane polymer suspension with a Janus molecular structure;

(2) preparing a fluorine-free stable super-hydrophobic fabric: diluting the organosilane polymer suspension with the Janus molecular structure by 1-20 times, and soaking the cleaned fabric in the organosilane polymer suspension for 4-300 seconds; and (3) carrying out filter pressing to remove redundant liquid, and then carrying out curing treatment at 120-180 ℃ for 2-8 minutes to obtain the water-based fluorine-free stable super-hydrophobic fabric.

2. The method for preparing the aqueous fluorine-free stable super-hydrophobic fabric according to claim 1, wherein the method comprises the following steps: the alkyl silane is at least one of methyltrimethoxy silane, dodecyl trimethoxy silane, hexadecyl trimethoxy silane and octadecyl trimethoxy silane, and the mass fraction of the alkyl silane in the reaction system is 0.6-12%.

3. The method for preparing the aqueous fluorine-free stable super-hydrophobic fabric according to claim 1, wherein the method comprises the following steps: the silane coupling agent is at least one of gamma-aminopropyltrimethoxysilane, gamma- (2, 3-epoxypropoxy) propyltrimethoxysilane and gamma-methacryloxypropyltrimethoxysilane, and the mass fraction of the silane coupling agent in a reaction system is 0.1-6%.

4. The method for preparing the aqueous fluorine-free stable super-hydrophobic fabric according to claim 1, wherein the method comprises the following steps: the inorganic acid is at least one of hydrochloric acid, sulfuric acid, acetic acid and oxalic acid, and the mass fraction of the inorganic acid in the reaction system is 0.08-6%.

5. The method for preparing the aqueous fluorine-free stable super-hydrophobic fabric according to claim 1, wherein the method comprises the following steps: the cohydrolysis condensation reaction is carried out at 20-60 ℃ for 4-27 hours.

Technical Field

The invention relates to a preparation method of a super-hydrophobic fabric, in particular to a preparation method of a water-based fluorine-free stable super-hydrophobic fabric, and belongs to the technical field of crossing of a bionic surface interface material and a functional textile.

Background

The super-hydrophobic surface has a very high water contact angle and a very low water rolling angle, has received great attention in recent years, and has great application prospects in the aspects of self-cleaning, corrosion prevention, icing prevention and the like. It is generally believed that the preparation of superhydrophobic surfaces benefits from the synergistic effect of low surface energy substances with micro-nano roughness structures. For the fabric, it is advantageous for it to form a superhydrophobic surface due to its inherent degree of roughness. The preparation method of the super-hydrophobic fabric is many, but most methods adopt fluorine-containing materials or adopt a preparation process involving organic solvents. Chinese patent CN102965910A uses perfluoro long chain silane to match with the roughness generated by alkaline solution etching, and obtains the contact angle larger than 150^oThe polyester fabric. CN04911918B prepared from fluoropolyether and having a contact angle of 165^oThe superhydrophobic fabric of (1). Although the super-hydrophobic fabric prepared by the methods has better super-hydrophobic performance, fluorine-containing materials such as perfluoro long-chain silane, fluoropolyether and the like are adopted. Because the long-carbon-chain fluorine-containing compound has good stability, but is difficult to naturally degrade and has certain bioaccumulation, the long-carbon-chain fluorine-containing compound has potential serious threats to the health and the natural environment of human beings, and the perfluorooctanoic acid (PFOA) and perfluorooctylsulfonyl compounds (PFOS) are also causedZ L201710388112.2 is used for soaking the fabric in a toluene solution containing polydimethylsiloxane prepolymer and curing agent thereof, and then the fabric is cured by a heat treatment mode to obtain the fluorine-free super-hydrophobic fabric, Z L201210561344.0 takes alcohol as a solvent and prepares a super-hydrophobic fabric finishing agent by silane hydrolysis, however, the methods have certain defects that (1) a large amount of volatile organic solvents such as ethanol and toluene are used in the preparation process, the organic solvents are harmful to human bodies and pollute the environment, unsafe factors and production cost in production are increased, more importantly, the method is not in accordance with the actual processing technology of a dye house, the method cannot be applied in large scale, the finishing process of the fabric of the dye house is carried out under an open system, so that (2) the used water-based super-hydrophobic fabric finishing agent only has the effect of water-based super-hydrophobic coating under normal temperature, and the super-hydrophobic fabric finishing agent has no easy damage to the normal temperature or super-hydrophobic coating and the super-hydrophobic fabric surface adhesion is easy to damage due to the micro-nano-water-based super-hydrophobic coating or super-hydrophobic fabric-water-based super-resistant coating.

At present, although there are some reports of aqueous fluorine-free super-hydrophobic coatings, the reports of the aqueous fluorine-free super-hydrophobic coatings applied to fabrics are few, and some problems exist. For example, CN108517154A reports an aqueous fluorine-free super-hydrophobic coating and a preparation method thereof, by adding an aqueous emulsion, inorganic nanoparticles, a low surface energy coupling agent, an organic solvent and water, an aqueous fluorine-free super-hydrophobic coating is prepared. The method still needs to add 1-10% of organic solvent and a certain amount of emulsifier to prevent the reaction system from phase separation. In addition, the stability of the obtained coating is not evaluated, and 2-30% of nanoparticles are added to change the color, flexibility and hand feeling of the fabric. CN105970610A is prepared by mixing silica hydrosol with dimethyl siloxane and long-chain alkyl silane coupling agent, emulsifying and dispersing the compound wax emulsion, and finally performing thermal treatment to hydrolyze and condense hydroxyl silicone oil and silane coupling agent with silica to prepare super-hydrophobic solution, thereby obtaining the stable super-hydrophobic fabric. However, this reaction requires heating at 80 to 95 ℃ for emulsification, which is disadvantageous for production. CN109518468A although stable superhydrophobic fabrics were obtained by adding silicone and organosilane to alkaline alcohol-water solution. However, the ethanol solvent is still used in the system, and cannot be used in a dye house due to safety reasons. At present, no relevant reports and application precedent exist for preparing super-hydrophobic fabrics with excellent super-hydrophobicity, super-hydrophobic hot-water property, water resistance and stability by adopting an aqueous fluorine-free method.

Disclosure of Invention

The invention aims to provide a preparation method of an aqueous fluorine-free stable super-hydrophobic fabric aiming at the problems of stable super-hydrophobic fabric prepared by the prior art.

Preparation of water-based fluorine-free stable super-hydrophobic fabric

(1) Preparation of organosilane polymer suspension of Janus molecular structure: water is used as a unique solvent, inorganic acid is used as a catalyst, and alkyl silane and a silane coupling agent are subjected to cohydrolysis condensation reaction to prepare the organosilane polymer suspension with the Janus molecular structure.

The alkyl silane is at least one of methyltrimethoxy silane, dodecyl trimethoxy silane, hexadecyl trimethoxy silane and octadecyl trimethoxy silane, and the mass fraction of the alkyl silane in the reaction system is 0.6-12%.

The silane coupling agent is at least one of gamma-aminopropyltrimethoxysilane, gamma- (2, 3-epoxypropoxy) propyltrimethoxysilane and gamma-methacryloxypropyltrimethoxysilane, and the mass fraction of the silane coupling agent in a reaction system is 0.1-6%.

The acid is at least one of hydrochloric acid, sulfuric acid, acetic acid and oxalic acid, and the mass fraction of the acid in the reaction system is 0.08-6%.

The cohydrolysis condensation reaction is carried out at 20-60 ℃ for 4-27 hours.

FIG. 1 is a Fourier spectrum of a powder obtained by drying a suspension of an organosilane polymer having a Janus molecular structure. In the figure, 2956 cm^-1And 2919 cm^-1In the hydrophobic chain being-CH₃and-CH₂Absorption peak of-group, 1020-1094 cm^-1The absorption peak is shown as Si-O-Si in the coupling chain, which indicates that the organosilane polymer has a Janus molecular structure and simultaneously contains a hydrophobic chain and a coupling chain.

(2) Preparing a fluorine-free stable super-hydrophobic fabric: diluting the organosilane polymer suspension with the Janus molecular structure by 1-20 times, and soaking the cleaned fabric in the organosilane polymer suspension for 4-300 seconds; and (3) carrying out filter pressing to remove redundant liquid, and then carrying out curing treatment at 120-180 ℃ for 2-8 minutes to obtain the water-based fluorine-free stable super-hydrophobic fabric.

Performance of two, super hydrophobic fabrics

1. Super hydrophobic property

FIG. 2 (a) shows the bouncing process of 10 mu L water drops on the super-hydrophobic fabric of the invention, (b) and (c) show the instant and infrared imaging of boiling water poured on the super-hydrophobic fabric of the invention, and (d) show the rolling angles of hot water at different temperatures on the super-hydrophobic fabric of the invention, and it can be known from FIG. 2 that the super-hydrophobic fabric prepared by the invention has excellent super-hydrophobic performance, the rolling angle of 10 mu L water drops is less than 10 degrees, the super-hydrophobic performance is excellent, the rolling angle of boiling water is less than 15 degrees, and the water resistance is excellent, and the water resistance grade is close to 5 grade.

2. Evaluation of stability

In order to prove that the super-hydrophobic fabric prepared by the invention has excellent stability, the stability of the super-hydrophobic fabric is systematically evaluated, including machine washing stability, abrasion stability and hot water stability, after various stability tests, the stability of the super-hydrophobic fabric is evaluated through the change of a rolling angle and a waterproof grade of 10 mu L water drops, and the stability is better when the change of the rolling angle and the waterproof grade of the water drops is smaller.

According to AATCC-20062A, placing 5cm × 15cm size fabric into a 1200m L container, simultaneously adding 50 steel balls with the diameter of 6mm, 150m L distilled water and 0.225g of laundry detergent, and washing at the constant temperature of 49 ℃ for 45 minutes each time, wherein the washing is equivalent to 5 times of washing in a household washing machine, and after 150 times of machine washing, the rolling angle of 10 mu L water drops is less than 15 degrees, and the waterproof grade is 3 (see figure 3 a).

And (3) according to ASTM D4966, testing by using a Martindale abrasion instrument, wherein the test load is 12kPa, after 10000 times of abrasion, the rolling angle of 10 mu L water drops is less than 20 degrees, and the waterproof grade is 3 grades (figure 3 b).

And (3) hot water stability, namely placing the fabric in boiling water for a certain time, and testing the change of the super-hydrophobicity and the water-proof performance, wherein after the fabric is boiled in the boiling water for 226 minutes, the rolling angle of 10 mu L water drops is less than 15 degrees, and the water-proof grade is greater than 4 grade (figure 3 c).

3. Detection of fluorine-containing conditions

The detection method comprises the following steps: STANDARD 100 by OEKO-TEX ()2018 test, certification and approval for ecological textile Standard 100 conditions.

Detecting items: perfluoro and polyfluoro compounds

And (3) testing results: see table 1:

。

in summary, compared with the prior art, the invention has the following advantages:

(1) according to the invention, through the synergistic effect of alkyl silane and a silane coupling agent and the control of co-hydrolysis condensation reaction parameters, the organosilane polymer suspension with the Janus molecular structure is prepared, the organosilane polymer simultaneously contains a hydrophobic chain and a coupling chain, the hydrophobic chain can endow the fabric with super-hydrophobicity, and the coupling chain can firmly bond the organosilane polymer on the surface of the fabric, so that the super-hydrophobic fabric is endowed with excellent super-hydrophobic hot-water property, water resistance and stability. The super-hydrophobic fabric can be made into functional clothes, and can keep lasting self-cleaning, prevent liquid pollution, prevent hot liquid from permeating and prevent scalding accidents; the self-cleaning umbrella can also be used for preparing a self-cleaning umbrella, can be dried instantly after being used, and is convenient for people to live;

(2) according to the invention, water is used as the only solvent, the use of organic solvents, emulsifiers, fluorine-containing materials and the like is completely avoided, the prepared super-hydrophobic fabric does not contain perfluoro and polyfluoro compounds, the process is green and environment-friendly, and the production safety is improved;

(3) the preparation method is simple in preparation process and low in cost, is completely suitable for the processing conditions of common dye factories, can be used for large-scale production of the water-based fluorine-free stable super-hydrophobic fabric, and is expected to be widely applied.

Drawings

FIG. 1 is a Fourier spectrum of a powder obtained by drying a suspension of an organosilane polymer having a Janus molecular structure.

FIG. 2 (a) shows the bouncing process of 10 mu L water drops on the inventive superhydrophobic fabric, (b) and (c) show the instant and infrared imaging of boiling water poured onto the inventive superhydrophobic fabric, and (d) show the rolling angles of hot water at different temperatures on the inventive superhydrophobic fabric.

Fig. 3 (a) is a graph showing the variation of the rolling angle and the waterproof grade of the superhydrophobic fabric by the number of random washings. (b) The rolling angle and the waterproof grade of the super-hydrophobic fabric change along with the abrasion times; (c) the rolling angle and the waterproof grade of the super-hydrophobic fabric change along with the soaking time in boiling water.

Detailed Description

The preparation method and performance of the aqueous fluorine-free stable super-hydrophobic fabric of the invention are further illustrated by the following specific examples.