阅读说明：本技术 一种具有仿生微/纳米分级结构SiO2的超疏水滤料、制备方法及其应用 (SiO with bionic micro/nano hierarchical structure2Super-hydrophobic filter material, preparation method and application thereof ) 是由 钱付平 董伟 周士安 李晴 吴胜华 鲁进利 韩云龙 于 2021-08-12 设计创作，主要内容包括：本发明涉及超疏水涂层制备技术领域,具体涉及一种具有仿生微/纳米分级结构SiO-(2)的超疏水滤料、制备方法及其应用；用低温溶胶-凝胶法水热技术,以正硅酸四乙酯(TEOS)为前驱体,甲基三乙氧基硅烷(MTES)为改性剂,γ-氨丙基三乙氧基硅烷(KH-550)为交联剂,在聚对苯二甲酸乙二醇酯(PET)滤料纤维基体上原位生长具有仿生微/纳米分级结构超疏水SiO-(2)粒子,形成具有类“荷叶表面”的乳突分级粗糙结构,从而赋予PET滤料超疏水性能,且改性后的超疏水PET滤料具有优异的机械稳定性和优良的自清洗性,改性的PET滤料静态综合过滤性能提升了36.96％,给PET材料提供了优异的疏水性能,且提高其静态综合过滤性能。(The invention relates to the technical field of preparation of super-hydrophobic coatings, in particular to SiO with a bionic micro/nano hierarchical structure 2 The super-hydrophobic filter material, the preparation method and the application thereof; by using a low-temperature sol-gel method hydrothermal technology, tetraethyl orthosilicate (TEOS) is taken as a precursor, Methyl Triethoxysilane (MTES) is taken as a modifier, gamma-aminopropyl triethoxysilane (KH-550) is taken as a cross-linking agent, and the super-hydrophobic SiO with the bionic micro/nano hierarchical structure grows in situ on a polyethylene glycol terephthalate (PET) filter material fiber substrate 2 Particles form a mastoid hierarchical coarse structure similar to the lotus leaf surface, so that the PET filter material is endowed with super-hydrophobic performance, the modified super-hydrophobic PET filter material has excellent mechanical stability and excellent self-cleaning performance, the static comprehensive filtering performance of the modified PET filter material is improved by 36.96%, the excellent hydrophobic performance is provided for the PET material, and the static comprehensive filtering performance is improved.)

1. SiO with bionic micro/nano hierarchical structure₂The preparation method of the super-hydrophobic filter material is characterized by comprising the following steps:

s1: adding ethanol, deionized water and ammonia water into the PET filter material, and magnetically stirring for 30min to obtain a first solution;

s2: dropping TEOS into ethanol, and magnetically stirring for 30min to obtain a second solution;

s3: dropwise adding the second solution obtained in the step S2 into the first solution obtained in the step S1, magnetically stirring for 6 hours, aging, adding ethanol, deionized water and ammonia water, and stirring for 30min to obtain a third solution;

s4: dropwise adding MTES into ethanol, and magnetically stirring for 30min to obtain a fourth solution;

s5: dropwise adding the fourth solution obtained in the step S4 into the first solution, magnetically stirring for 4 hours, and aging for 24 hours to obtain a mixed solution;

s6: dripping a silane coupling agent KH550 into the mixed solution obtained in the step S4, adjusting the pH value, hermetically stirring for 2h, aging for 24h, taking out, and drying at 60 ℃ for 2h to obtain SiO with a bionic micro/nano hierarchical structure₂The superhydrophobic filter material of (1).

2. The SiO with biomimetic micro/nano hierarchical structure of claim 1₂The preparation method of the superhydrophobic filter material is characterized in that the dropping speed in the steps S2, S3, S4, S5 and S6 is 1 drop/S.

3. The SiO with biomimetic micro/nano hierarchical structure of claim 1₂The preparation method of the super-hydrophobic filter material is characterized in that the aging time in the step S3 is 0-24 h.

4. The SiO with biomimetic micro/nano hierarchical structure of claim 1₂The preparation method of the super-hydrophobic filter material is characterized in that the mass of TEOS in the step S2 is 1-5 g, the mass of MTES in the step S4 is 1-5 g, and the total mass of TEOS and MTES is 6 g.

5. The SiO with biomimetic micro/nano hierarchical structure of claim 1₂The preparation method of the superhydrophobic filter material is characterized in that the silane coupling agent in the step S6 is KH550 with a volume ratio of 0.1 v%.

6. The SiO with biomimetic micro/nano hierarchical structure of claim 1₂The preparation method of the super-hydrophobic filter material is characterized in that,the pH is adjusted to 11 in step S6.

7. SiO with bionic micro/nano hierarchical structure prepared by the preparation method of any one of claims 1 to 6₂The superhydrophobic filter material of (1).

8. The SiO of claim 7, having a biomimetic micro/nano hierarchical structure₂The super-hydrophobic filter material is applied to a bag type dust collector in a high-humidity environment.

Technical Field

The invention relates to the technical field of preparation of super-hydrophobic coatings, in particular to SiO with a bionic micro/nano hierarchical structure₂The super-hydrophobic filter material, the preparation method and the application thereof.

Background

Industries such as iron and steel, cement, mine and the like are taken as basic prop industries of a country, and have attracted extensive attention due to the problems of high energy consumption, high pollution and the like, and particularly, air pollution caused by inhalable Particles (PM) seriously affects human health. Among them, the flue gas discharged by the pollutants in the steel industry is the key point of industrial treatment due to the fact that the types of the pollutants are multiple, the types of dust particles are multiple and the water content is high. At present, the requirement of all countries around the world on the emission of industrial pollutants is more and more strict, the traditional electrostatic dust removal technology is difficult to meet the requirement, and the traditional electrostatic dust removal technology is replaced by a bag type dust removal technology. However, the high water content in flue gas of steel, cement, mine and the like can cause the phenomena of dewing and bag pasting of the filter material of the bag type dust collector, so that the filter resistance of the bag type dust collector is increased, the energy consumption is increased, the strength of the filter bag is further reduced, and the service life is prolonged. In recent years, development of a filter material having super-hydrophobic properties, thereby improving the filtering properties thereof, has been receiving attention from researchers. The silane coupling agent modified silicon dioxide nano particles endow the PET filter material with super-hydrophobicity, and can well solve the problems of bag pasting, blockage and the like of dust when a bag type dust collector is used for treating high-humidity dust.

In view of the above-mentioned drawbacks, the inventors of the present invention have finally obtained the present invention through a long period of research and practice.

Disclosure of Invention

The invention aims to prepare a filter material with super-hydrophobic property, solve the problems of dust bag pasting and blockage of a bag type dust collector during high-humidity dust treatment, and provide a SiO with a bionic micro/nano hierarchical structure₂The super-hydrophobic filter material, the preparation method and the application thereof.

In order to realize the aim, the invention discloses SiO with a bionic micro/nano hierarchical structure₂Is disclosedThe preparation method of the hydrophobic filter material comprises the following steps:

s1: adding ethanol, deionized water and ammonia water into the PET filter material, and magnetically stirring for 30min to obtain a first solution;

s2: dropping TEOS into ethanol, and magnetically stirring for 30min to obtain a second solution;

s3: dropwise adding the second solution obtained in the step S2 into the first solution obtained in the step S1, magnetically stirring for 6 hours, aging, adding ethanol, deionized water and ammonia water, and stirring for 30min to obtain a third solution;

s4: dropwise adding MTES into ethanol, and magnetically stirring for 30min to obtain a fourth solution;

s5: dropwise adding the fourth solution obtained in the step S4 into the first solution, magnetically stirring for 4 hours, and aging for 24 hours to obtain a mixed solution;

s6: adding a silane coupling agent dropwise into the mixed solution obtained in the step S4, adjusting the pH value, hermetically stirring for 2h, aging for 24h, taking out, and drying at 60 ℃ for 2h to obtain SiO with a bionic micro/nano hierarchical structure₂The superhydrophobic filter material of (1).

The dropping speed in the steps S2, S3, S4, S5 and S6 is 1 drop/S.

The aging time in the step S3 is 0-24 h.

The mass of TEOS in the step S2 is 1-5 g, the mass of MTES in the step S4 is 1-5 g, and the total mass of TEOS and MTES is 6 g.

The silane coupling agent in step S6 is KH550 at a volume ratio of 0.1 v%.

The pH is adjusted to 11 in step S6.

The invention also discloses the SiO with the bionic micro/nano hierarchical structure prepared by the preparation method₂And the application of the super-hydrophobic filter material in a bag type dust collector in a high-humidity environment.

Compared with the prior art, the invention has the beneficial effects that: the invention relates to SiO with a bionic micro/nano hierarchical structure₂The method for preparing the super-hydrophobic filter material and the application thereof adopt a simple low-temperature sol-gel method and gamma-aminopropyl triethoxysilane (KH-550) modified bionicMicro/nano hierarchical structure SiO₂The hierarchical structure similar to the lotus leaf surface and the excellent hydrophobic property are provided, and the prepared PET filter material has the advantages of no toxicity, no pollution, super-hydrophobicity and improvement of the comprehensive filtering property.

Preparing the super-hydrophobic SiO with the micro-nano hierarchical structure by using a polyethylene terephthalate (PET) filter material as a matrix and a low-temperature sol-gel method and using tetraethyl orthosilicate (TEOS) as a precursor, Methyltriethoxysilane (MTES) as a modifier and gamma-aminopropyltriethoxysilane (KH-550) as a cross-linking agent₂The particles endow the PET filter material with super-hydrophobic performance, improve the bag pasting phenomenon of the PET filter material during high-humidity dust treatment, prolong the service life of the PET filter material and reduce the operation and maintenance cost.

The invention studies the mechanical stability of the filter material before and after modification, cuts the modified PET filter material sample to 2.5 x 2.5cm, puts the sample under a weight of 100g, pulls the sample 20cm on 800 mesh sand paper along the same direction at a speed of 1cm/s, and the process is defined as a cycle. After the total pulling distance is 5m (25 cycles), the modified PET filter material still keeps super-hydrophobicity, and shows good mechanical stability.

The super-hydrophobic surface similar to the lotus leaf surface has excellent self-cleaning performance, and the self-cleaning performance of the modified PET filter material is investigated. Cutting the modified PET filter material sample into a size of 5 multiplied by 2.5cm, uniformly coating 0.3g of dust with the humidity of 10% on the surface of the sample, inclining the sample by 10 degrees from the horizontal plane, keeping for 24 hours, dripping 50 mu L of water drops on the surface of the sample at the speed of 1 s/drop and observing the rolling behavior of the water drops. On the experimental surface, water drops on the surface of the modified PET filter material quickly roll off and take away dust, the dust on the surface of the filter material is basically stripped, the interior of a sample is not soaked, and the excellent self-cleaning characteristic is shown.

Drawings

FIG. 1 is a bionic micro/nano roughness hierarchical structure SiO₂Schematic diagram of modified super-hydrophobic PET filter material;

FIG. 2 is SiO₂Schematic diagram of in-situ hydrophobization and KH550 crosslinking;

FIG. 3 is the surface microtopography of PET before and after modification, wherein a and b are original PET; c. d is TMK-PET-1; e. f is TMK-PET-2; g. h is TMK-PET-3; i. j is TMK-PET-4; k. l is TMK-PET-5;

FIG. 4SiO₂The particle size and distribution ratio of the nanoparticles are (a) TEOS @ MTES, (b) TEOS @ MTES @ KH550

FIG. 5 shows the contact angle (WCA) and water loss angle (WSA) (a), water droplet morphology on PET surface (b), water droplet morphology on modified PET surface (c) for different PET samples;

FIG. 6 shows the evaluation parameters of filtration performance, (a) is the filtration efficiency (. eta.) and the pressure drop (. DELTA.P), and (b) is the quality factor (Q)_F)

FIG. 7 is a sandpaper wear test chart, (a) is a single sandpaper wear test of a self-made abrasive tool; (b) WCA after each abrasion test; (c) is the static contact angle morphology of the water drop after the 25 th cycle abrasion.

FIG. 8 shows a dust self-cleaning process with a surface humidity of 10%, wherein (a) is PET and (b) is modified PET.

Detailed Description

The above and further features and advantages of the present invention are described in more detail below with reference to the accompanying drawings.

Example 1

Bionic micro/nano hierarchical coarse structure SiO₂The preparation schematic diagram of the modified super-hydrophobic TEOS @ MTES @ [email protected] PET (TMK @ PET) filter material is shown in figure 1.

The method comprises the following steps: pretreatment of PET filter material

Before sample preparation, the PET filter material is ultrasonically cleaned for 3 times by ethanol, and dried for 2 hours in a drying oven at the temperature of 60 ℃;

step two: preparation of SiO₂Sol gel

(1) Solution (I): placing the pretreated PET filter material into a beaker under a room temperature environment, adding 50mL of ethanol, 20mL of deionized water and 2mL of ammonia water, and placing the mixture into a water bath magnetic stirrer to stir for 30 min;

(2) solution II: adding 10mL of ethanol into another beaker, dropwise adding 1g of TEOS into the beaker at a rate of 1 drop/s, and placing the beaker in a water bath magnetic stirrer to stir for 30 min;

(3) solution (c): adding the solution dropwise into the solution IStirring in a water bath magnetic stirrer for 6h, aging for 24h, adding 50mL ethanol, 20mL deionized water and 2mL ammonia water, and stirring for 30min to obtain SiO₂And (3) sol.

Step three: preparation of hydrophobically modified SiO₂Sol gel

(1) Solution (iv): adding 10mL of ethanol into a beaker, dropwise adding 5g of MTES into the beaker at 1 drop/s, and stirring for 30min by a water bath magnetic stirrer;

(2) solution fifth: dropwise adding the solution IV into the solution III, and stirring for 4 hours in a water bath magnetic stirrer; aging for 24h to obtain hydrophobically modified SiO₂And (3) sol.

Step four: preparation of KH550 modified bionic micro/nano hierarchical structure SiO₂Sol gel

Adding KH550 with volume ratio of 0.1 v% into the solution at 1 drop/s drop by drop (v), adjusting pH to 11, stirring for 2h under sealed condition, aging for 24h, taking out PET filter material, and drying in 60 deg.C oven for 2h to obtain bionic micro-nano hierarchical coarse structure SiO₂The modified hydrophobic TEOS @ MTES @ [email protected] PET-1(TMK @ PET-1) filter material.

Example 2

The method comprises the following steps: pretreatment of PET filter material

Before sample preparation, the PET filter material is ultrasonically cleaned for 3 times by ethanol, and dried for 2 hours in a drying oven at the temperature of 60 ℃;

step two: preparation of SiO₂Sol gel

(1) Solution (I): placing the pretreated PET filter material into a beaker under a room temperature environment, adding 50mL of ethanol, 20mL of deionized water and 2mL of ammonia water, and placing the mixture into a water bath magnetic stirrer to stir for 30 min;

(2) solution II: adding 10mL of ethanol into another beaker, dropwise adding 2g of TEOS into the beaker at a rate of 1 drop/s, and placing the beaker in a water bath magnetic stirrer to stir for 30 min;

(3) solution (c): dropwise adding the solution II into the solution I, placing the solution I in a water bath magnetic stirrer to stir for 6 hours, aging the solution for 24 hours, adding 50mL of ethanol, 20mL of deionized water and 2mL of ammonia water to stir for 30 minutes to obtain SiO₂And (3) sol.

Step three: preparation of hydrophobically modified SiO₂Sol gel

(1) Solution (iv): adding 10mL of ethanol into a beaker, dropwise adding 4g of MTES into the beaker at 1 drop/s, and placing the beaker in a water bath magnetic stirrer to stir for 30 min;

(2) solution fifth: dropwise adding the solution IV into the solution III, and stirring for 4 hours in a water bath magnetic stirrer; aging for 24h to obtain hydrophobically modified SiO₂And (3) sol.

Step four: preparation of KH550 modified bionic micro/nano hierarchical structure SiO₂Sol gel

Adding KH550 with volume ratio of 0.1 v% into the solution at 1 drop/s drop by drop (v), adjusting pH to 11, stirring for 2h under sealed condition, aging for 24h, taking out PET filter material, and drying in 60 deg.C oven for 2h to obtain bionic micro-nano hierarchical coarse structure SiO₂The modified super-hydrophobic TEOS @ MTES @ [email protected] PET-2(TMK @ PET-2) filter material.

Example 3

The method comprises the following steps: pretreatment of PET filter material

Before sample preparation, the PET filter material is ultrasonically cleaned for 3 times by ethanol, and dried for 2 hours in a drying oven at the temperature of 60 ℃;

step two: preparation of SiO₂Sol gel

(1) Solution (I): placing the pretreated PET filter material into a beaker under a room temperature environment, adding 50mL of ethanol, 20mL of deionized water and 2mL of ammonia water, and placing the mixture into a water bath magnetic stirrer to stir for 30 min;

(2) solution II: adding 10mL of ethanol into another beaker, dropwise adding 3g of TEOS into the beaker at a rate of 1 drop/s, and placing the beaker in a water bath magnetic stirrer to stir for 30 min;

(3) solution (c): dropwise adding the solution II into the solution I, placing the solution I in a water bath magnetic stirrer to stir for 6 hours, aging the solution for 24 hours, adding 50mL of ethanol, 20mL of deionized water and 2mL of ammonia water to stir for 30 minutes to obtain SiO₂And (3) sol.

Step three: preparation of hydrophobically modified SiO₂Sol gel

(1) Solution (iv): adding 10mL of ethanol into a beaker, dropwise adding 3g of MTES into the beaker at 1 drop/s, and stirring for 30min by a water bath magnetic stirrer;

(2) solution fifth: dropwise adding the solution IV into the solution III, and stirring for 4 hours in a water bath magnetic stirrer; aging of the mixtureObtaining hydrophobic modified SiO after 24 hours₂And (3) sol.

Step four: preparation of KH550 modified bionic micro/nano hierarchical structure SiO₂Sol gel

Adding KH550 with volume ratio of 0.1 v% into the solution at 1 drop/s drop by drop (v), adjusting pH to 11, stirring for 2h under sealed condition, aging for 24h, taking out PET filter material, and drying in 60 deg.C oven for 2h to obtain bionic micro-nano hierarchical coarse structure SiO₂The modified super-hydrophobic TEOS @ MTES @ [email protected] PET-3(TMK @ PET-3) filter material.

Example 4

The method comprises the following steps: pretreatment of PET filter material

Before sample preparation, the PET filter material is ultrasonically cleaned for 3 times by ethanol, and dried for 2 hours in a drying oven at the temperature of 60 ℃;

step two: preparation of SiO₂Sol gel

(1) Solution (I): placing the pretreated PET filter material into a beaker under a room temperature environment, adding 50mL of ethanol, 20mL of deionized water and 2mL of ammonia water, and placing the mixture into a water bath magnetic stirrer to stir for 30 min;

(2) solution II: adding 10mL of ethanol into another beaker, dropwise adding 4g of TEOS into the beaker at a rate of 1 drop/s, and placing the beaker in a water bath magnetic stirrer to stir for 30 min;

(3) solution (c): dropwise adding the solution II into the solution I, placing the solution I in a water bath magnetic stirrer to stir for 6 hours, aging the solution for 24 hours, adding 50mL of ethanol, 20mL of deionized water and 2mL of ammonia water to stir for 30 minutes to obtain SiO₂And (3) sol.

Step three: preparation of hydrophobically modified SiO₂Sol gel

(1) Solution (iv): adding 10mL of ethanol into a beaker, dropwise adding 2g of MTES into the beaker at 1 drop/s, and stirring for 30min by a water bath magnetic stirrer;

(2) solution fifth: dropwise adding the solution IV into the solution III, and stirring for 4 hours in a water bath magnetic stirrer; aging for 24h to obtain hydrophobically modified SiO₂And (3) sol.

Step four: preparation of KH550 modified bionic micro/nano hierarchical structure SiO₂Sol gel

Adding KH550 with volume ratio of 0.1 v% into the solution drop by drop at 1 drop/s, adjustingThe pH value of the agent is 11, the mixture is hermetically stirred for 2h, aged for 24h, taken out of the PET filter material and dried in a 60 ℃ oven for 2h to obtain the bionic micro-nano hierarchical coarse structure SiO₂The modified super-hydrophobic TEOS @ MTES @ [email protected] PET-4(TMK @ PET-4) filter material.

Example 5

The method comprises the following steps: pretreatment of PET filter material

Before sample preparation, the PET filter material is ultrasonically cleaned for 3 times by ethanol, and dried for 2 hours in a drying oven at the temperature of 60 ℃;

step two: preparation of SiO₂Sol gel

(1) Solution (I): placing the pretreated PET filter material into a beaker under a room temperature environment, adding 50mL of ethanol, 20mL of deionized water and 2mL of ammonia water, and placing the mixture into a water bath magnetic stirrer to stir for 30 min;

(2) solution II: adding 10mL of ethanol into another beaker, dropwise adding 5g of TEOS into the beaker at a rate of 1 drop/s, and placing the beaker in a water bath magnetic stirrer to stir for 30 min;

(3) solution (c): dropwise adding the solution II into the solution I, placing the solution I in a water bath magnetic stirrer to stir for 6 hours, aging the solution for 24 hours, adding 50mL of ethanol, 20mL of deionized water and 2mL of ammonia water to stir for 30 minutes to obtain SiO₂And (3) sol.

Step three: preparation of hydrophobically modified SiO₂Sol gel

(1) Solution (iv): adding 10mL of ethanol into a beaker, dropwise adding 1g of MTES into the beaker at a rate of 1 drop/s, and stirring for 30min by using a water bath magnetic stirrer;

(2) solution fifth: dropwise adding the solution IV into the solution III, and stirring for 4 hours in a water bath magnetic stirrer; aging for 24h to obtain hydrophobically modified SiO₂And (3) sol.

Step four: preparation of KH550 modified bionic micro/nano hierarchical structure SiO₂Sol gel

Adding KH550 with volume ratio of 0.1 v% into the solution at 1 drop/s drop by drop (v), adjusting pH to 11, stirring for 2h under sealed condition, aging for 24h, taking out PET filter material, and drying in 60 deg.C oven for 2h to obtain bionic micro-nano hierarchical coarse structure SiO₂A modified hydrophobic TEOS @ MTES @ [email protected] PET-5(TMK @ PET-5) filter material.

The samples obtained in examples 1 to 5The sample surface micro-topography was analyzed with a field emission scanning electron microscope as shown in fig. 3. FIGS. 3(a) and (b) show that the original PET fibers have smooth and flat surfaces, are randomly interlaced and staggered with each other, and have fine gaps among the fibers. As can be seen from FIGS. 3(c) and (d), a small amount of micro-nano SiO is deposited on the surface of the TMK @ PET-1 filter material₂Microspheres, which are unevenly distributed on the surface of the filter material and are partially SiO₂The microspheres are agglomerated into micron-sized microspheres, and a plurality of nano-scale SiO appears on the surfaces of the microspheres₂The microsphere antenna has irregular multi-level micro-nano rough appearance on the surface of the fiber. As can be seen from FIGS. 3(e), (g), (i) and (k), increasing the TEOS/MTES mass ratio results in SiO loading on the fiber surface₂The number of nanoparticles is gradually increased. As can be seen from FIGS. 3(f), (h), (j) and (l), increasing the TEOS/MTES mass ratio results in SiO loading on the fiber surface₂The particle size range of the nano particles is gradually increased and then is close to uniformity. In FIGS. 3(i) and (j), the surface of the TMK @ PET-4 fiber is coated with SiO of different particle sizes₂The microspheres are wrapped, and the shapes of multi-stage folds and concave-convex parts which are more uniformly distributed appear, so that the thickness of the surface of the filter material is increased. However, in FIGS. 3(k) and (l), the TMK @ PET-5 fiber surface is almost uniformly sized SiO₂The microspheres are coated because the mass ratio of TEOS/MTES is too large, resulting in excessive hydrolysis of TEOS to form SiO₂The nano particles can not be condensed and modified by a small amount of MTES/KH550, so that the rough appearance of a multilevel structure is less on the surface of the filter material, and simultaneously SiO₂Too much amount of microspheres will increase the filtration resistance of the filter material.

Nano SiO in the range of 0.4 nm-10 microns is measured by a nano particle size analyzer₂The size of the microspheroidal particles and their size distribution are shown in FIGS. 4(a) and 4 (b). Among them, in FIG. 4(a), it can be found that SiO is present when the TEOS/MTES mass ratio is 1/5₂The particle size of the nano particles is normally distributed, the average particle size is 1106.0nm, the main particle size is 396.1-1106.0 nm, and the particle size distribution is uniform. SiO with increasing TEOS/MTES mass ratio₂The particle size distribution of the nano particles is wider, the average particle size is gradually increased, then slowly decreased and then sharply decreased, and more particle size peak values are generated, particularlyWhen the mass ratio of TEOS/MTES is 4/2, three peaks with large difference of particle size appear, and the particle size distribution is 220.0 nm-5560.0 nm. When the mass ratio of TEOS/MTES is 5/1, the average particle size is only 198.2nm, but the particle size distribution range is the widest, and is from 58.8nm to 5560.0 nm. FIG. 4(b), which shows SiO after KH550 was added to a TEOS/MTES solution having a mass ratio of 1/5₂The average particle size of the nano particles is increased from 1106.0nm to 3816.0nm, the particle size distribution is 7.6 nm-1718.0 nm, and the range is expanded compared with that without adding KH 550. KH550 modified SiO with increasing TEOS/MTES mass ratio₂The average particle size of the nanoparticles gradually decreases and then decreases, and the particle size distribution tends to gradually decrease and then expand and decrease. Particularly, when the mass ratio of TEOS/MTES is 4/2, SiO after KH500 is added₂The average particle size of the nanoparticles increased in a small range, but the particle size distribution increased to 105.7nm to 5560.0nm, which is the largest in all samples, with three peaks of large differences in particle size. SiO with increasing TEOS/MTES mass ratio₂The particle size distribution of the nano particles is gradually increased, the average particle size is gradually increased, then slowly decreased and then sharply decreased, and simultaneously, more particle size peak values are generated. KH550 modified SiO₂The particle size distribution of the nano particles is greatly increased, and when the mass ratio of TEOS/MTES is 1/5-4/2, SiO is₂The uniformity and range of the distribution of the nano particles are gradually improved to present bimodal normal distribution, so that the micro-nano multilevel roughness of the surface of the PET fiber can be better increased, and the possibility of super-hydrophobic preparation is created.

The contact angle (WCA) and the rolling angle (WSA) of water on the surface of the filter material were measured using a contact angle measuring instrument, the dropping amount was 5. mu.L/drop, and the number of measurement points was 5 for each sample, and the average values were taken, as shown in FIGS. 5(a), (b), and (c). Wherein the WCA of the original PET is 127.7 + -3.6 degrees, the WSA is 38.6 + -4.5 degrees, the WCA of TEOS @ MTES @ [email protected] PET-1 is increased to 144.5 + -3.2 degrees, and the increase of WCA is due to SiO after TEOS hydrolysis₂The nanoparticles increase the coarsening of the surface morphology of the fiber and the MTES @ KH550 decreases the surface free energy. The WCA increases with increasing TEOS/MTES mass ratio, and reaches 4/2160.9 + -2.8 deg., and then continue to increase the TEOS/MTES mass ratio, there is a sharp decrease in WCA. In addition, when TEOS @ MTES @ KH550 was modified, the angle of run off (WSA) was below 10 °, with the lowest WSA being as low as 5.9. + -. 2.5 °, showing excellent superhydrophobicity. When the mass ratio of TEOS/MTES was 5/1, a large amount of SiO had-OH₂The nanoparticles tend to be uniform in size, with some reduction in roughness, while not having enough MTES @ KH550 to reduce the surface free energy, resulting in a sharp reduction in WCA at the fiber surface.

NaCl (1.0 wt%) aerosol particles simulating dust particles are emitted by a filter material comprehensive performance test bench, and the filter performance (Quality Factor, Q) of the filter material is evaluated through a filter efficiency (eta) and a pressure drop curve (delta P) under the conditions that the filter air speed is 5.33cm/s, the system flow is 32L/min and the dust emission flow is 6L/min_F) As shown in fig. 6(a) and (b). The filtration efficiency eta of the original PET filter material to NaCl aerosol particles with PM0.3 is 93.15%, the pressure loss delta P is 45Pa, the filtration efficiency is obviously increased along with the increase of the mass ratio of TEOS/MTES, the pressure loss is also increased, the increase amplitude of other samples is not large (about 10Pa or less is increased) except that the pressure loss of TMK @ PET-5 is obviously increased, because the TMK @ PET-5 is coated with SiO₂The amount of nanoparticles increased, and the TMK @ PET-5 sample gave the best filtration efficiency and the greatest filtration pressure loss compared to all samples. According to the results of fig. 6, the removal efficiency for PM0.3 is in order: PET<[email protected]<[email protected]<[email protected]<[email protected]<TMK @ PET-5, the pressure loss for filtering PM0.3 is as follows in sequence: PET<[email protected]<[email protected]<[email protected]<[email protected]<[email protected]。Q_FIn the order of size of PET<[email protected]<[email protected]<[email protected]<[email protected]<TMK @ PET-4. It is worth noting that the TMK @ PET-4 filter material has the best overall filtering efficiency (eta: 99.12%, delta P: 58Pa, Q) on PM0.3_F: 0.0816) which is about 36.96 percent higher than that of the original PET filter material.

And (3) wear testing: the modified TMK @ PET-4 filter material sample was cut to a size of 2.5 × 2.5cm, placed on 800 mesh sandpaper having a mass of 100g, and then pulled at a speed of 1cm/s for 20cm in the direction of the scale, which was defined as one cycle, as shown in fig. 7(a), (b), and (c). After 5 cycles, the WCA remained essentially unchanged (with a tendency to increase locally), indicating that the wear did not change its roughness. As the number of abrasions increased, there was a more pronounced decrease in WCA for the sample due to structural damage to the filter material. Furthermore, it was observed that after a total pull distance of 5m (25 cycles), the water contact angle of the sample was 151 ± 1.6 °, still maintaining superhydrophobicity.

Self-cleaning experiments: 0.3g of dust having a humidity of 10% was uniformly coated on the surface of a sample of a PET filter material, the sample was inclined at 10 ℃ from the horizontal plane and kept for 24 hours, and then 50. mu.L of water droplets were dropped on the surface of the sample at a speed of 1 s/drop and the rolling behavior thereof was observed, as shown in FIGS. 8(a) and (b). Water drops on the surface of an original PET filter material sample roll slowly or stop, dust basically remains on the surface, the water drops enter the fibers, and the wetting behavior is obvious. And water drops on the surface of the TMK @ PET-4 filter material quickly roll off and take away dust, the dust on the surface of the filter material is basically stripped completely, the interior of a sample is not soaked, and the excellent self-cleaning characteristic is shown. The TMK @ PET-4 filter material sample after the self-cleaning test is dried in an oven at 60 ℃, and then the WCA of the sample is measured to be 157.1 +/-2.3 degrees, and the super-hydrophobic characteristic is still maintained.

The foregoing is merely a preferred embodiment of the invention, which is intended to be illustrative and not limiting. It will be understood by those skilled in the art that various changes, modifications and equivalents may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.