1. Based on polypyrrole/nanometer TiO₂The preparation method of the super-hydrophobic material is characterized by comprising the following steps:

(1) pulverizing the base material to particle size of 20-40 mesh, soaking in anhydrous ethanol, and cleaningDrying, soaking the treated base material in pyrrole solution, stirring for reaction for 2-5h, and adding FeCl₃Uniformly mixing the solution, standing for 1-5h at 5 ℃, filtering, and drying at 50 ℃;

(2) adding tetrabutyl titanate into absolute ethyl alcohol to form a solution A, simultaneously mixing deionized water, acetic acid and the absolute ethyl alcohol to form a solution B, and respectively and simultaneously placing the solutions A and B in an ultrasonic oscillator to oscillate for 5 min;

(3) adding the straws treated in the step (1) into the solution B prepared in the step (2) under the condition of water bath at 30 ℃, then slowly dropwise adding the solution A into the solution B while stirring, after dropwise adding, continuously stirring the mixed liquid at 30 ℃ for reacting for 24 hours until the mixed solution gradually becomes light blue, and then filtering to dry the straws at 60 ℃ to obtain the straws/polypyrrole/titanium dioxide;

(4) uniformly mixing absolute ethyl alcohol, a modifier and deionized water, adding glacial acetic acid, stirring at normal temperature, reacting for 3-8h, soaking the straw/polypyrrole/titanium dioxide obtained in the step (3) in the mixture, standing for 4h, filtering and drying to obtain the super-hydrophobic material.

2. The polypyrrole/nano TiO-based material according to claim 1₂The preparation method of the super-hydrophobic material is characterized in that the concentration of the pyrrole solution in the step (1) is 0.4mol/L, FeCl is added₃The concentration of the solution is 0.15mol/L, the pyrrole solution and FeCl₃The volume ratio of the solution was 1: 1.

3. The polypyrrole/nano TiO-based material according to claim 1₂The preparation method of the super-hydrophobic material is characterized in that the mass-volume ratio of tetrabutyl titanate to absolute ethyl alcohol in the solution A in the step (2) is 10g/35 mL.

4. The polypyrrole/nano TiO-based material according to claim 1₂The preparation method of the super-hydrophobic material is characterized in that the mass ratio of the deionized water to the acetic acid to the absolute ethyl alcohol in the solution B in the step (2) is 1:1: 3.5.

5. The polypyrrole/nano TiO-based material according to claim 1₂The method for preparing a superhydrophobic material of (1), wherein the dropping speed of the solution a in the step (3) is 1 drop/second.

6. The polypyrrole/nano TiO-based material according to claim 1₂The preparation method of the super-hydrophobic material is characterized in that the volume ratio of absolute ethyl alcohol in the step (4): modifying agent: deionized water: glacial acetic acid 2000:40:5: 1.

7. A polypyrrole/nano TiO based material according to claim 1 or 6₂The preparation method of the super-hydrophobic material is characterized in that the modifier is one of hexadecyl trimethoxy silane, octadecyl trimethoxy silane, methyl trimethoxy silane, propyl trimethoxy silane, phenyl trimethoxy silane, stearic acid, 1H,2H, 2H-perfluorodecyl triethoxy silane or trimethoxy (1H,1H,2H, 2H-heptadecafluorodecyl) silane.

8. The polypyrrole/nano TiO-based material according to claim 1₂The preparation method of the super-hydrophobic material is characterized in that the base material is corn straw, wood chips, cotton cloth or sponge.

9. Polypyrrole/nano TiO based material according to claims 1-8₂The super-hydrophobic material is applied to oil-water separation and oil adsorption.

Background

Under the advocation of the green development concept, some achievements are achieved in the aspect of environmental control in recent years, but the situation of water pollution control is still severe. According to relevant research reports, at least over 3000 million tons of oil are discharged into water bodies through various channels every year. The oily wastewater not only reduces the photosynthesis of underwater algae, but also causes the dissolved oxygen in water to be rapidly reduced, even causes the death of organisms in water, and destroys the ecological balance of a water system. Meanwhile, the oily wastewater has complex components and is difficult to degrade, and many components are toxic and harmful, and are accumulated in a human body through biological chain enrichment, so that the human health is harmed. The super-hydrophobic super-oleophilic material can selectively absorb oil from an oil-water mixture, and has obvious advantages when being used for removing oil pollution and recovering the oil.

At present, metal nets, inorganic nano particles, sponges, porous ceramics and the like are mostly used as matrixes in research, and many problems exist in practical application, such as difficult construction of rough structures on the surfaces of the metal nets and strict experimental requirements; inorganic nano-particles and porous ceramics have unstable structures and are easy to fall off, and once the inorganic nano-particles and the porous ceramics fall into oil products and water, the health of human beings and other organisms is threatened; the hydrophobic modification with the fluorine-containing organic compound having low surface energy causes environmental pollution and is not favorable for mass production.

Therefore, how to provide a preparation method of a super-hydrophobic material with simple operation, low cost and environmental friendliness is a problem to be solved by those skilled in the art.

Disclosure of Invention

In view of the above, the invention provides a preparation method of a super-hydrophobic/super-oleophylic coating, which solves the problems of high cost and easy pollution in the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme:

based on polypyrrole/nanometer TiO₂The preparation method of the super-hydrophobic material comprises the following steps:

(1) crushing the base material to 20-40 meshes, soaking and cleaning the base material by absolute ethyl alcohol, drying the base material, soaking the treated base material in a pyrrole solution, stirring the base material to react for 2-5 hours, and adding FeCl₃Mixing the solutions, standing at 5 deg.C for 60-300min, filtering, and oven drying at 50 deg.C;

(2) adding tetrabutyl titanate into absolute ethyl alcohol to form a solution A, simultaneously mixing deionized water, acetic acid and the absolute ethyl alcohol to form a solution B, and respectively and simultaneously placing the solutions A and B in an ultrasonic oscillator to oscillate for 5 min;

(3) adding the straws treated in the step (1) into the solution B prepared in the step (2) under the condition of water bath at 30 ℃, then slowly dropwise adding the solution A into the solution B while stirring, after dropwise adding, continuously stirring the mixed liquid at 30 ℃ for reacting for 24 hours until the mixed solution gradually becomes light blue, and then filtering to dry the straws at 60 ℃ to obtain the straws/polypyrrole/titanium dioxide;

(4) uniformly mixing absolute ethyl alcohol, a modifier and deionized water, adding glacial acetic acid, stirring at normal temperature, reacting for 3-8h, soaking the straw/polypyrrole/titanium dioxide obtained in the step (3) in the mixture, standing for 4h, filtering and drying to obtain the super-hydrophobic material.

Preferably, the concentration of the pyrrole solution in the step (1) is 0.4mol/L, and FeCl is adopted₃The concentration of the solution is 0.15mol/L, the pyrrole solution and FeCl₃The volume ratio of the solution was 1: 1.

Preferably, the mass-to-volume ratio of tetrabutyl titanate to absolute ethyl alcohol in the solution A in the step (2) is 10g/35 mL.

Preferably, the mass ratio of the deionized water to the acetic acid to the absolute ethyl alcohol in the solution B in the step (2) is 1:1: 3.5.

Preferably, the dropping speed of the solution A in the step (3) is 1 drop/second.

Preferably, the volume ratio of the absolute ethyl alcohol in the step (4): modifying agent: deionized water: glacial acetic acid 2000:40:5: 1.

Preferably, the modifier is one of hexadecyl trimethoxy silane, octadecyl trimethoxy silane, methyl trimethoxy silane, propyl trimethoxy silane, phenyl trimethoxy silane, stearic acid, 1H,2H, 2H-perfluorodecyl triethoxy silane or trimethoxy (1H,1H,2H, 2H-heptadecafluorodecyl) silane.

Preferably, the base material is corn straw, wood chips, cotton cloth or sponge.

The invention also provides application of the material prepared by the scheme, namely application in oil-water separation and oily material adsorption.

According to the technical scheme, compared with the prior art, the polypyrrole/nano TiO based material is disclosed and provided₂The preparation method and the application of the super-hydrophobic material have the following beneficial effects:

the polypyrrole is coated on the surface of the straw by adopting an in-situ polymerization method, TiO2 sol is prepared by a sol-gel method, and nano TiO is directly modified on the surface of the polypyrrole₂And finally, modifying the particles by using a low-surface-energy substance hexadecyl trimethoxy silane to obtain the novel super-hydrophobic super-oleophylic straw material. The super-hydrophobic straw material can effectively adsorb and separate oil stains and organic solvents such as soybean oil, ethyl acetate, benzene, engine oil and the like in water, has good chemical stability and mechanical properties, and can be repeatedly used. The method has the advantages of high efficiency, low cost, environmental protection and the like, and has important significance for treating oil-containing pollutants.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a diagram showing a state of a corn stalk substrate material, super-hydrophobic/super-oleophilic corn stalks and water drops on the super-hydrophobic/super-oleophilic corn stalks;

FIG. 2 is a scanning electron microscope image of a corn stalk substrate and super-hydrophobic/super-oleophilic corn stalks;

FIG. 3 is an infrared spectrum of a corn stover substrate and super-hydrophobic/super-oleophilic corn stover;

FIG. 4 is a graph showing the measurement of the hydrophobic angle of a corn stalk substrate and super-hydrophobic/super-oleophilic corn stalks;

FIG. 5 is a drawing of an oil-water separation experiment of super-hydrophobic/super-oleophylic corn stalks;

FIG. 6 is a graph showing the adsorption performance of a corn stalk substrate and super-hydrophobic/super-oleophilic corn stalks;

FIG. 7 is a diagram showing the state of wood chip base material, super-hydrophobic/super-oleophilic wood chips and water drops on super-hydrophobic/super-oleophilic wood chips;

FIG. 8 is a graph showing the measurement of the hydrophobic angle of super-hydrophobic/super-oleophilic wood chips;

FIG. 9 is a diagram showing the state of cotton substrate material and water drops on super-hydrophobic/super-oleophilic cotton;

FIG. 10 is a graph showing the measurement of the hydrophobic angle of superhydrophobic/superoleophilic cotton;

FIG. 11 is a diagram showing a state of a cotton cloth base material, super-hydrophobic/super-oleophilic cotton cloth and water drops on the super-hydrophobic/super-oleophilic cotton cloth;

FIG. 12 is a graph showing the measurement of the hydrophobic angle of superhydrophobic/superoleophilic cotton.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Based on polypyrrole/nano TiO₂The preparation method of the super-hydrophobic material comprises the following steps:

(1) pulverizing corn stalks to a particle size of 20-40 meshes, soaking and cleaning the corn stalks by absolute ethyl alcohol, drying the corn stalks, soaking the treated base material in 0.4mol/L pyrrole solution, magnetically stirring the base material for reaction for 2 hours, and adding 0.15mol/L FeCl which has the same volume with the pyrrole solution₃Uniformly mixing the solution, standing for 80min at 5 ℃, filtering, and drying in a 50 ℃ oven;

(2) adding 10g of tetrabutyl titanate into 35mL of absolute ethyl alcohol to form a solution A, simultaneously mixing 10g of deionized water, 10g of acetic acid and 35g of absolute ethyl alcohol to form a solution B, and respectively and simultaneously placing the solutions A and B in an ultrasonic oscillator to oscillate for 5min so as to uniformly mix the solutions A and B;

(3) adding the straws treated in the step (1) into the solution B prepared in the step (2) under the condition of water bath at 30 ℃, then slowly dropwise adding the solution A into the solution B at the speed of 1 drop/second while stirring, after dropwise adding, continuously stirring the mixed liquid at 30 ℃ for reacting for 24 hours, wherein the mixed solution gradually becomes light blue, and then filtering to dry the straws at 60 ℃ to obtain the straws/polypyrrole/titanium dioxide;

(4) adding 100mL of absolute ethyl alcohol and hexadecyl trimethoxy silane C₁₉H₄₂SiO₃Placing 2mL and 0.25mL of deionized water in a beaker, magnetically stirring for 10min, uniformly mixing, adding 0.05mL of glacial acetic acid, stirring at normal temperature for reaction for 4h (the cup mouth is covered by a film to prevent ethanol from volatilizing in the stirring process), soaking the straw/polypyrrole/titanium dioxide obtained in the step (3) in the solution, standing for 4h, filtering and drying to obtain the super-hydrophobic material represented as PPy/TiO₂/HDTMS。

Test examples

Observation and comparison of the raw base material and the material prepared in example 1, as shown in FIG. 1, wherein FIG. 1a is raw corn stover, FIG. 1b is super-hydrophobic/super-oleophilic corn stover, and FIG. 1c is a state diagram of water drops on the super-hydrophobic/super-oleophilic corn stover, PPy/TiO prepared₂the/HDTMS surface is black due to the black color of the surface-coated polypyrrole, as shown in FIG. 1c, the water drops are in PPy/TiO₂The surface of HDTMS corn stalk can keep spherical water bead shape.

Scanning electron microscopy was used to determine the material obtained in example 1 and the original substrateAnalyzing the micro-morphology of the rice straw, wherein the result is shown in figure 2, the original straw is composed of cellulose and lignin, the surface structure of the original straw is smooth, and is shown in figure 2 a; after the polypyrrole/titanium dioxide is modified, the roughness of the surface of the straw is increased, and a large amount of nano TiO is modified on the surface of the straw₂Particles of PPy/TiO₂The micro-morphology of the corn straw modified by HDTMS is obviously changed, as shown in FIG. 2b, the rough structure of the surface and the modification of the low surface energy substance HDTMS jointly promote the realization of the super-hydrophobic property.

The chemical components of the material were analyzed by fourier transform infrared spectroscopy (FTIR), and the results are shown in fig. 3, wherein C ═ N, C ═ C, C-C, and C-N stretching vibration peaks of the pyrrole ring were 1632cm in length, respectively^-1,1540cm^-1,1453cm^-1And 1380cm^-1And successfully modifying the polypyrrole on the surface of the corn straw. In addition, at 2922 and 2851cm^-1Two small peaks at (A) are-CH in hexadecyl₃And- (CH)₂)_n-The C-H stretching vibration peak proves that silane is successfully grafted on the surface of the corn straw after HDTMS modification; the stretching vibration peak of Si-O-Si (located at 1100-800 cm)^-1Between ranges) is superposed with the C-O stretching vibration peak of the straw in the map.

The larger the hydrophobic angle of the water drop on the surface of the material, the stronger the hydrophobic property of the material. As shown in FIG. 4, when the hydrophobic angle of the raw corn stalks is measured, the surface contact angle is 0 degrees and the hydrophobic angle of the super-hydrophobic super-oleophilic stalks is 152 degrees when the liquid drops are dropped on the surfaces of the stalks.

Oil-water separation test:

and (3) setting up a test device to perform an oil-water separation test, as shown in the attached figure 5. Mixing 20mL of carbon tetrachloride dyed with Sudan 3 and 20mL of water dyed with methylene blue in equal volume, pouring the oil-water mixture into a separation device, and judging PPy/TiO according to separation effect₂HDTMS separation effect on oil-water mixture. As shown in figure 5a, red carbon tetrachloride completely passes through the super-hydrophobic super-oleophilic straw, while blue water cannot pass through, so that oil-water separation is realized. PPy/TiO₂The HDTMS can realize the rapid separation of an oil-water mixture.

As shown in FIG. 5b, Sudan 3-dyed liquid paraffin was added to distilled water, and PPy/TiO was added₂After HDTMS, the liquid paraffin was quickly absorbed and the material was filtered off to give clear water. The prepared super-hydrophobic super-oleophilic PPy/TiO₂The HDTMS material can be used for oil-water separation of heavy oil and can also be used for oil-water separation of light oil.

And (3) measuring saturated oil absorption:

under the laboratory conditions, 5 kinds of oil including liquid ethyl acetate, paraffin, benzene, engine oil and corn oil are respectively prepared, a plurality of corn straw raw materials to be detected and the PPy/TiO prepared in example 1 are prepared₂HDTMS material, the quality of each group is controlled to be 0.3g, and the adsorption capacity of the straw to which oil is the largest is researched.

In the experimental determination process, the oil products in the above 5 are respectively added into a prepared clean beaker, then the materials are respectively put into the oil product beakers, soaked for three minutes, filtered by a colander for taking out, and weighed by an analytical balance. In order to study the change of the hydrophobic property of the corn stalks before and after hydrophobic modification, the adsorption property of the corn stalks before and after modification was analyzed, and the results are shown in table 1 and figure 6.

TABLE 1 comparison of oil absorption Capacity before and after modification of corn stover (g/g)

According to experimental data, compared with the original straw, the modified maize straw PPy/TiO₂The HDTMS material greatly enhances the adsorption capacity of various oils, and is expected to be applied to the treatment of oily wastewater to realize the recovery of oil products.

In addition, in this experiment, the corn stalk substrate was replaced with the wood chip substrate, and the comparative graph of the prepared material and the raw wood chips and the state graph of water drops on the surface of the hydrophobic material are shown in fig. 7, wherein fig. 7a is the raw wood chip graph, fig. 7b is the hydrophobic oleophilic material graph prepared by the method of example 1 with the wood chips as the substrate, and fig. 7c is the state graph of water drops on the surface of the hydrophobic material. As shown in the attached figure 8, the hydrophobic angle of the super-hydrophobic super-oleophilic material of the wood chip substrate is 168 degrees by measurement.

In this test, the corn stalk substrate was replaced with cotton, and a comparison graph of the prepared material and cotton and a state graph of water droplets on the surface of the hydrophobic material are shown in fig. 9, in which fig. 9a is a raw cotton graph, and fig. 7b is a state graph of water droplets on the surface of the hydrophobic material. As shown in the attached figure 10, the hydrophobic angle of the super-hydrophobic and super-oleophilic material of the cotton substrate is 157 degrees.

In this test, the corn stalk substrate was replaced with cotton cloth, and the comparative graph of the prepared material and the original cloth and the state graph of water beads on the surface of the hydrophobic material are shown in FIG. 11, in which FIG. 11a is the original cotton flower graph, FIG. 11b is the hydrophobic oleophylic material prepared by the method of example 1 using cotton cloth as the substrate, and FIG. 11c is the state graph of water beads on the surface of the hydrophobic material. As shown in figure 12, the hydrophobic angle of the super-hydrophobic and super-oleophilic material of the cotton substrate is 162 degrees.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.