Preparation Method of Polymer / Cotton Fiber Composite-Based Superhydrophobic / Superoleophilic Material

Abstract

The present invention relates to the technical field of superhydrophobic / superhydrophilic materials, and specifically to a preparation method of a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material. In an alcohol system dissolved with dipentaerythritol penta- / hexa-acrylate, untreated cotton fibers, short fluorocarbon chain-containing monomers, crosslinking monomers, initiators, and polyamino compounds are added. Among them, dipentaerythritol penta- / hexa-acrylate and polyamino compounds undergo a gelling effect to form a composite polymer gel system. The composite polymer gel system is placed in a high-temperature environment to promote the in-situ thermal polymerization of reactive monomers therein, thereby obtaining a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material. The material prepared by the present invention has a high specific surface area, high porosity, biodegradability, and superhydrophobic / superoleophilic properties.

Description

Technical Field

[0001] The present invention relates to the technical field of superhydrophobic / superhydrophilic materials, and specifically to a preparation method of a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material. Background Art

[0002] Currently, the commonly used methods for constructing superhydrophobic / superoleophilic materials include: femtosecond laser method, chemical etching method, sol-gel method, induced deposition method, layer-by-layer self-assembly method, etc. These methods can effectively prepare superhydrophobic / superoleophilic materials, but they all have certain limitations. The femtosecond laser method requires high-performance equipment and has a high cost; the chemical etching method also relies on special equipment but has certain hazards; the sol-gel method mainly relies on expensive surface energy reagents and perfluorinated compounds with biological toxicity; the durability of the products of the induced deposition method is poor; the layer-by-layer self-assembly method has many steps, takes a long time, and the structural stability of the products is not good. In summary, it is still challenging to prepare superhydrophobic / superoleophilic materials with excellent durability, chemical stability, and recyclability.

[0003] Compounds containing long fluorocarbon chains (the number of carbon atoms in the fluorocarbon chain ≥ 8) are persistent in the environment, will accumulate in organisms, and have the disadvantages of non-degradability and environmental pollution. Therefore, the country is gradually phasing out and banning such compounds. By introducing compounds containing short fluorocarbon chains (the number of carbon atoms in the fluorocarbon chain ≤ 6), superhydrophobic / superoleophilic materials can be constructed without polluting the environment, and the products are degradable and environmentally friendly; cotton fiber is an abundant natural degradable cellulose fiber, which has the advantages of environmental protection, low price, high oil adsorption efficiency, etc. At the same time, raw cotton is also a hydrophobic material because its surface contains low surface energy substances such as wax, and can participate in the construction of superhydrophobic / superoleophilic materials.

[0004] In-situ polymerization is a method in which monomers undergo self-polymerization or copolymerization with crosslinking monomers in-situ on a substrate, and gradually deposit and then coat on the surface of the substrate. It is expected to form a micro-nano hierarchical rough structure on the surface of the corresponding substrate, and can endow the surface energy chemical composition of the material while constructing the rough structure. It has the advantages of not relying on high-cost equipment and expensive surface energy modifiers, and good controllability. Summary of the Invention

[0005] In view of the deficiencies of the prior art, the present invention provides a method for preparing a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material, which adds untreated cotton fibers, short fluorocarbon chain-containing monomers, crosslinking monomers, initiators, and polyamino compounds to an alcohol system dissolved with dipentaerythritol penta- / hexa-acrylate, wherein dipentaerythritol penta- / hexa-acrylate and the polyamino compound undergo a gelling effect to form a composite polymer gel system; the composite polymer gel system is placed in a high-temperature environment to promote the thermal-initiated in-situ polymerization of the reactive monomers therein, thereby obtaining a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material.

[0006] To achieve the above object, the technical solution provided by the present invention is a method for preparing a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material, which includes the following steps: Weigh dipentaerythritol penta- / hexa-acrylate, and completely dissolve the dipentaerythritol penta- / hexa-acrylate in absolute ethanol; add 1H,1H,2H,2H-hexafluorobutyl methacrylate, and mix evenly; add divinylbenzene to make it fully dissolved; add azobisisobutyronitrile to make it fully dissolved; add raw cotton to make the raw cotton evenly dispersed in the reaction liquid phase; add ethylenediamine-capped polyethyleneimine to make it fully dissolved, and ensure that the raw cotton is evenly dispersed in the reaction liquid phase, let it stand, and after the reaction is completed, a polymer / cotton fiber composite gel system is formed; the polymer / cotton fiber composite gel system product is placed in a high-temperature environment for in-situ polymerization reaction to obtain a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material.

[0007] Preferably, the mass ratio of 1H,1H,2H,2H-hexafluorobutyl methacrylate to dipentaerythritol penta- / hexa-acrylate is 33-67:100.

[0008] Preferably, the mass ratio of divinylbenzene to dipentaerythritol penta- / hexa-acrylate is 6-33:100.

[0009] Preferably, the mass ratio of azobisisobutyronitrile to dipentaerythritol penta- / hexa-acrylate is 6:100.

[0010] Preferably, the raw cotton is Xinjiang upland cotton, and the mass ratio of the raw cotton to dipentaerythritol penta- / hexa-acrylate is 2.6:100.

[0011] Preferably, the mass ratio of ethylenediamine-capped polyethyleneimine to dipentaerythritol penta- / hexa-acrylate is 13-20:100.

[0012] Preferably, when adding ethylenediamine-capped polyethyleneimine, the reaction temperature is controlled at room temperature and the reaction time is 12 h.

[0013] Preferably, the reaction temperature for the in-situ polymerization reaction is controlled at 80 °C and the reaction time is 4 h.

[0014] A polymer / cotton fiber composite superhydrophobic / superoleophilic material, which is prepared by using the preparation method of the polymer / cotton fiber composite superhydrophobic / superoleophilic material described in any one of the above.

[0015] Use of a polymer / cotton fiber composite superhydrophobic / superoleophilic material, wherein the polymer / cotton fiber composite superhydrophobic / superoleophilic material is applied to oil-water separation.

[0016] The preparation method of the above polymer / cotton fiber composite superhydrophobic / superoleophilic material is as follows: First, untreated cotton fibers, short fluorocarbon chain monomers, crosslinking monomers, initiators and polyamino compounds are added to an alcohol system dissolved with dipentaerythritol penta- / hexa-acrylate, wherein dipentaerythritol penta- / hexa-acrylate and polyamino compounds undergo gelation to form a composite polymerization gel system; the composite polymerization gel system is placed in a high-temperature environment to promote the thermal-initiated in-situ polymerization of the reactive monomers therein, thereby obtaining a polymer / cotton fiber composite superhydrophobic / superoleophilic material. For this polymer / cotton fiber composite superhydrophobic / superoleophilic material, its different special wetting behaviors exhibited towards the water phase and the oil phase are further explored; the application stability of the polymer / cotton fiber composite superhydrophobic / superoleophilic material is evaluated through cyclic oil removal experiments; the oil-water separation application of the polymer / cotton fiber composite superhydrophobic / superoleophilic material is demonstrated by performing oil removal tests on the polymer / cotton fiber composite superhydrophobic / superoleophilic material for oil-water mixtures.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The method of the present invention uses the environmentally friendly biomass material cotton fiber as the base, which is inexpensive and easy to obtain; and uses compounds containing short fluorocarbon chains, which are green and environmentally friendly and easy to promote on a large scale.

[0019] The present invention provides a preparation method of a polymer / cotton fiber composite superhydrophobic / superoleophilic material, which is inspired by the superwetting phenomenon in nature, uses the environmentally friendly biomass material cotton fiber as the base, combines the gelation of dipentaerythritol penta- / hexa-acrylate and polyamino compounds, and then endows the material with superhydrophobic and superoleophilic properties through in-situ polymerization. Compared with other materials, it has the advantages of low cost, convenience, environmental protection, greenness, biodegradability, etc., and has excellent practical significance.

[0020] The polymer / cotton fiber composite superhydrophobic / superoleophilic material prepared by the method of the present invention has a high specific surface area, high porosity, biodegradability and superhydrophobic / superoleophilic properties.

[0021] The polymer / cotton fiber composite superhydrophobic / superoleophilic material prepared by the present invention has good superhydrophobicity and excellent stability.

[0022] The polymer / cotton fiber composite-based superhydrophobic / superoleophilic material prepared by the present invention has good oil-phase absorption performance.

[0023] The polymer / cotton fiber composite-based superhydrophobic / superoleophilic material prepared by the present invention has excellent oil-water separation performance. Description of the Drawings

[0024] Figure 1 Optical photograph of the polymerization gel system of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention;

[0025] Figure 2 Optical photograph of the polymerization gel system after in-situ polymerization of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention;

[0026] Figure 3 Schematic diagram of the appearance of the air layer when the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention is immersed in water;

[0027] Figure 4 Schematic diagram of the dynamic anti-wetting process of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention;

[0028] Figure 5 Schematic diagram of the dynamic oil absorption process of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention;

[0029] Figure 6 Schematic diagram of the static stability of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention;

[0030] Figure 7 Schematic diagram of the maximum oil absorption capacity of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention;

[0031] Figure 8 Schematic diagram of the cyclic maximum oil absorption capacity (n-hexane) of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention;

[0032] Figure 9 Schematic diagram of the wetting performance (n-hexane) during the test of the cyclic maximum oil absorption capacity of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention;

[0033] Figure 10 Schematic diagram of the cyclic maximum oil absorption capacity (dichloromethane) of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention;

[0034] Figure 11Schematic diagram of the wetting performance (dichloromethane) during the test of the maximum oil absorption of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention;

[0035] Figure 12 Schematic diagram of the dynamic anti-wetting property of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention after five cycles of maximum oil absorption test for n-hexane;

[0036] Figure 13 Schematic diagram of the dynamic anti-fouling property of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention after five cycles of maximum oil absorption test for n-hexane;

[0037] Figure 14 Schematic diagram of the self-cleaning property of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention after five cycles of maximum oil absorption test for n-hexane;

[0038] Figure 15 Schematic diagram of the dynamic anti-wetting property of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention after five cycles of maximum oil absorption test for dichloromethane;

[0039] Figure 16 Schematic diagram of the dynamic anti-fouling property of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention after five cycles of maximum oil absorption test for dichloromethane;

[0040] Figure 17 Schematic diagram of the self-cleaning property of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention after five cycles of maximum oil absorption test for dichloromethane;

[0041] Figure 18 Dynamic process of light oil-water separation during the oil-water separation application of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention;

[0042] Figure 19 Dynamic process of heavy oil-water separation during the oil-water separation application of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material in Example 1 of the present invention. Detailed implementation mode

[0043] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following provides a detailed description of the specific embodiments of the present invention with reference to the accompanying drawings. Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0044] Example 1

[0045] The present invention provides a method for preparing a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material, which includes the following steps:

[0046] Step 1: Weigh 1.5 g of dipentaerythritol penta- / hexa-acrylate and add it to a glass container. Then add 10 ml of anhydrous ethanol to the glass container to completely dissolve the dipentaerythritol penta- / hexa-acrylate in the anhydrous ethanol.

[0047] Step 2: Add 1 g of hexafluorobutyl methacrylate with a short fluorocarbon chain (the number of carbon atoms in the fluorocarbon chain is 4) to the glass container in which the dipentaerythritol penta- / hexa-acrylate is completely dissolved in Step 1, and mix them evenly.

[0048] Step 3: Add 0.2 g of divinylbenzene to the container in Step 2 and dissolve it fully.

[0049] Step 4: Add 0.1 g of azobisisobutyronitrile to the container in Step 3 and dissolve it fully.

[0050] Step 5: Add 0.04 g of raw cotton to the container in Step 4 to uniformly disperse the raw cotton in the reaction liquid phase.

[0051] Step 6: Add 0.23 g of ethylenediamine-terminated polyethyleneimine to the container in Step 5 and dissolve it fully, ensuring that the raw cotton remains uniformly dispersed in the reaction liquid phase. Then, without moving the glass container, let it stand. After the reaction is completed, a uniform and stable milky white polymer / cotton fiber composite gel system is formed.

[0052] Step 7: Place the well-formed milky white polymer / cotton fiber composite gel system product in Step 6 in a high-temperature environment for in-situ polymerization reaction to obtain a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material.

[0053] Example 2

[0054] The present invention provides a method for preparing a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material, which includes the following steps:

[0055] Step 1: Weigh 1.5 g of dipentaerythritol penta- / hexa-acrylate and add it to a glass container. Then add 10 ml of absolute ethanol to the glass container to completely dissolve the dipentaerythritol penta- / hexa-acrylate in the absolute ethanol;

[0056] Step 2: Add 0.8 g of hexafluorobutyl methacrylate with a short fluorocarbon chain (the number of carbon atoms in the fluorocarbon chain is 4) to the glass container in which the dipentaerythritol penta- / hexa-acrylate is completely dissolved in Step 1, and mix them evenly;

[0057] Step 3: Add 0.2 g of divinylbenzene to the container in Step 2 and dissolve it completely;

[0058] Step 4: Add 0.1 g of azobisisobutyronitrile to the container in Step 3 and dissolve it completely;

[0059] Step 5: Add 0.04 g of raw cotton to the container in Step 4 to evenly disperse the raw cotton in the reaction liquid phase;

[0060] Step 6: Add 0.2 g of ethylenediamine-terminated polyethyleneimine to the container in Step 5 and dissolve it completely, and ensure that the raw cotton is still evenly dispersed in the reaction liquid phase. Let it stand still and do not move the glass container. After the reaction is completed, a uniform and stable milky white polymer / cotton fiber composite gel system is formed;

[0061] Step 7: Place the well-shaped milky white polymer / cotton fiber composite gel system product in Step 6 in a high-temperature environment for in-situ polymerization reaction to obtain a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material.

[0062] Example 3

[0063] The present invention provides a preparation method of a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material, which includes the following steps:

[0064] Step 1: Weigh 1.5 g of dipentaerythritol penta- / hexa-acrylate and add it to a glass container. Then add 10 ml of absolute ethanol to the glass container to completely dissolve the dipentaerythritol penta- / hexa-acrylate in the absolute ethanol;

[0065] Step 2: Add 1 g of hexafluorobutyl methacrylate with a short fluorocarbon chain (the number of carbon atoms in the fluorocarbon chain is 4) to the glass container in which the dipentaerythritol penta- / hexa-acrylate is completely dissolved in Step 1, and mix them evenly;

[0066] Step 3: Add 0.1 g of divinylbenzene to the container in Step 2 and dissolve it completely;

[0067] Step 4: Add 0.1 g of azobisisobutyronitrile to the container in Step 3 and dissolve it completely;

[0068] Step Five: Add 0.04 g of raw cotton into the container in Step Four to evenly disperse the raw cotton in the reaction liquid phase;

[0069] Step Six: Add 0.25 g of ethylene diamine-terminated polyethyleneimine into the container in Step Five, dissolve it completely, and ensure that the raw cotton remains evenly dispersed in the reaction liquid phase. Let it stand still and do not move the glass container anymore. After the reaction is completed, a uniform and stable milky white polymer / cotton fiber composite gel system is formed;

[0070] Step Seven: Place the well-formed milky white polymer / cotton fiber composite gel system product in Step Six in a high-temperature environment for in-situ polymerization reaction to obtain a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material.

[0071] Example 4

[0072] The present invention provides a preparation method of a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material, which includes the following steps:

[0073] Step One: Weigh 1.5 g of dipentaerythritol penta- / hexa-acrylate and add it into a glass container. Then add 10 ml of absolute ethanol into the glass container to completely dissolve dipentaerythritol penta- / hexa-acrylate in the absolute ethanol;

[0074] Step Two: Add 0.5 g of hexafluorobutyl methacrylate containing a short fluorocarbon chain (the number of carbon atoms in the fluorocarbon chain is 4) into the glass container in which dipentaerythritol penta- / hexa-acrylate is completely dissolved in Step One, and mix them evenly;

[0075] Step Three: Add 0.5 g of divinylbenzene into the container in Step Two and dissolve it completely;

[0076] Step Four: Add 0.1 g of azobisisobutyronitrile into the container in Step Three and dissolve it completely;

[0077] Step Five: Add 0.04 g of raw cotton into the container in Step Four to evenly disperse the raw cotton in the reaction liquid phase;

[0078] Step Six: Add 0.3 g of ethylene diamine-terminated polyethyleneimine into the container in Step Five, dissolve it completely, and ensure that the raw cotton remains evenly dispersed in the reaction liquid phase. Let it stand still and do not move the glass container anymore. After the reaction is completed, a uniform and stable milky white polymer / cotton fiber composite gel system is formed;

[0079] Step Seven: Place the well-formed milky white polymer / cotton fiber composite gel system product in Step Six in a high-temperature environment for in-situ polymerization reaction to obtain a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material.

[0080] Example 5

[0081] The present invention provides a method for preparing a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material, which comprises the following steps:

[0082] Step 1: Weigh 1.5 g of dipentaerythritol penta- / hexa-acrylate and add it to a glass container. Then add 10 ml of absolute ethanol to the glass container to completely dissolve the dipentaerythritol penta- / hexa-acrylate in the absolute ethanol;

[0083] Step 2: Add 0.9 g of hexafluorobutyl methacrylate with a short fluorocarbon chain (the number of carbon atoms in the fluorocarbon chain is 4) to the glass container in which the dipentaerythritol penta- / hexa-acrylate is completely dissolved in Step 1, and mix them evenly;

[0084] Step 3: Add 0.2 g of divinylbenzene to the container in Step 2 and dissolve it fully;

[0085] Step 4: Add 0.1 g of azobisisobutyronitrile to the container in Step 3 and dissolve it fully;

[0086] Step 5: Add 0.04 g of raw cotton to the container in Step 4 to evenly disperse the raw cotton in the reaction liquid phase;

[0087] Step 6: Add 0.2 g of ethylene diamine-terminated polyethyleneimine to the container in Step 5 and dissolve it fully, ensuring that the raw cotton remains evenly dispersed in the reaction liquid phase. Let it stand still without moving the glass container. After the reaction is completed, a uniform and stable milky white polymer / cotton fiber composite gel system is formed;

[0088] Step 7: Place the well-formed milky white polymer / cotton fiber composite gel system product in Step 6 in a high-temperature environment for in-situ polymerization reaction to obtain a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material.

[0089] Table 1 is a summary table of the masses of the added materials in Examples 1 to 5;

[0090]

[0091] It should be noted that the step operations of Examples 1 to 5 are basically the same, only the ratios of some reagents are different. The wetting characteristics, oil phase absorption performance, determination of the maximum cyclic oil absorption, stability of the absorbed oil, anti-pollution performance, anti-wet absorption of light oil, and anti-wet absorption of heavy oil of the products of Examples 1 to 5 are respectively measured. The product characteristics are not very different. The following takes the test process of the product of Example 1 as an example for illustration.

[0092] I. Conduct the wetting characteristic determination of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material. Refer to Figures 1-6 which shows the schematic diagram of the wetting characteristics of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material;

[0093] Among them, referring to Figure 1 and Figure 2 are the product images of Step 6 and Step 7 in the invention content;

[0094] As Figure 3 shown, when the polymer / cotton fiber composite superhydrophobic / superoleophilic material is immersed in deionized water, an obvious air layer can be clearly observed between the deionized water and the product; it floats naturally and finally floats on the surface of the deionized water. The part exposed to the air is not wetted, and the part under the deionized water still maintains good anti-wetting performance.

[0095] Referring to Figure 4 shown, when the prepared polymer / cotton fiber composite superhydrophobic / superoleophilic material is placed on a 10° angle platform and water droplets are dropped onto its surface, it can be observed that there is no wetting on the surface of the product after anti-wetting on the 10° angle platform; 10 μL of deionized water is extruded using a microinjector and placed statically on the polymer / cotton fiber composite superhydrophobic / superoleophilic material, and the contact angle between the water droplet and the product is measured to be 158°.

[0096] Referring to Figure 5 , when the polymer / cotton fiber composite superhydrophobic / superoleophilic material is placed flat on the test bench and n-hexane is dropped, the n-hexane is quickly absorbed, indicating that the product has excellent oleophilic performance;

[0097] Referring to Figure 6 , 10 μL of deionized water is extruded using a microinjector and placed statically on the polymer / cotton fiber composite superhydrophobic / superoleophilic material, and the whole process is recorded and observed until the water droplet completely evaporates. From left to right, the states of the polymer / cotton fiber composite superhydrophobic / superoleophilic material at 20 min, 40 min, 60 min, 80 min, and 95 min are shown. The contact angle is measured every five minutes during the whole process. The whole process lasts for 1 h 40 min. After the water droplet completely evaporates, it can be observed that the product still maintains a good anti-wetting state, and there is no residual water stain or small water droplet on the surface. Thus, it can be shown that the product has good superhydrophobicity and excellent stability.

[0098] II. Conduct the oil phase absorption performance test of the polymer / cotton fiber composite superhydrophobic / superoleophilic material. Referring to Figures 7-11 , which shows the oil phase absorption performance of the polymer / cotton fiber composite superhydrophobic / superoleophilic material.

[0099] Referring to Figure 7 , for the determination of the maximum oil absorption amount of the polymer / cotton fiber composite superhydrophobic / superoleophilic material, the specific determination method includes:

[0100] S1. The maximum oil absorption of the polymer / cotton fiber composite superhydrophobic / superoleophilic material was tested using three different light oils and three different heavy oils, including n-hexane, kerosene, and petroleum ether; dichloromethane, chloroform, and benzyl chloride.

[0101] S2. Measure the dry weight of the polymer / cotton fiber composite superhydrophobic / superoleophilic material;

[0102] S3. Place the dry polymer / cotton fiber composite superhydrophobic / superoleophilic material into a container filled with an appropriate amount of oil, gently squeeze it, and turn it over repeatedly to completely expel the air bubbles until the product is saturated with oil absorption;

[0103] S4. Take out the polymer / cotton fiber composite superhydrophobic / superoleophilic material from the container, weigh it, and record the mass of the product after being saturated with oil absorption;

[0104] S5. Use the ratio of the difference between the dry weight before oil absorption and the mass after oil absorption to the dry weight before oil absorption to represent the overall oleophilic ability of the polymer / cotton fiber composite superhydrophobic / superoleophilic material, that is, the maximum oil absorption per unit mass.

[0105] See Figure 8 、 Figure 10 , for the determination of the cyclic maximum oil absorption of the polymer / cotton fiber composite superhydrophobic / superoleophilic material, the specific determination method includes:

[0106] H1. Respectively use light oil (n-hexane) and heavy oil (dichloromethane) as the oils for testing the cyclic maximum oil absorption of the polymer / cotton fiber composite superhydrophobic / superoleophilic material to represent the different absorption situations of the product for light oil and heavy oil.

[0107] H2. Measure the dry weight of the polymer / cotton fiber composite superhydrophobic / superoleophilic material;

[0108] H3. Place the dry polymer / cotton fiber composite superhydrophobic / superoleophilic bulk material into a container filled with an appropriate amount of oil, gently squeeze it, and turn it over repeatedly to completely expel the air bubbles until the product is saturated with oil absorption;

[0109] H4. Take out the polymer / cotton fiber composite superhydrophobic / superoleophilic material from the container, weigh it, and record the mass of the polymer / cotton fiber composite superhydrophobic / superoleophilic material after being saturated with oil absorption;

[0110] H5. After weighing, dry the polymer / cotton fiber composite superhydrophobic / superoleophilic material to its dry weight under standard temperature and humidity;

[0111] H6. Repeat steps H1 - H5 five times. Use the ratio of the difference between the dry weight before each oil absorption and the mass after oil absorption to the dry weight before oil absorption to represent the maximum oil absorption per unit mass of the polymer / cotton fiber composite superhydrophobic / superoleophilic material.

[0112] Test the maximum oil absorption, cyclic maximum oil absorption, and wetting performance during the process of the polymer / cotton fiber composite superhydrophobic / superoleophilic material. The results are as Figures 7-11 :

[0113] The average maximum oil absorption of the polymer / cotton fiber composite superhydrophobic / superoleophilic material for light oil is 1.219 (g / g), and for heavy oil is 2.514 (g / g). The maximum oil absorption for heavy oil is approximately twice that of light oil.

[0114] The cyclic maximum oil absorption of the polymer / cotton fiber composite superhydrophobic / superoleophilic material for n - hexane slightly decreases with the increase in the number of cycles. However, overall, the number of cycles has little effect, indicating that the product has good sustainability and can be recycled multiple times.

[0115] The cyclic maximum oil absorption of the polymer / cotton fiber composite superhydrophobic / superoleophilic material for dichloromethane slightly increases with the increase in the number of cycles. However, overall, the number of cycles has little effect, indicating that the product has good sustainability and can be recycled multiple times.

[0116] After the cyclic maximum oil absorption test of the polymer / cotton fiber composite superhydrophobic / superoleophilic material for n - hexane, the measured contact angles are all greater than 153°, and the rolling angle is equal to 1°. After the cyclic maximum oil absorption test for dichloromethane, the measured contact angles are all greater than 159°, and the rolling angle is equal to 1°. This shows that the product has good stability and still maintains good superhydrophobicity after multiple cycles of oil absorption.

[0117] III. Test the stability of the polymer / cotton fiber composite superhydrophobic / superoleophilic bulk material for absorbing oil and its anti - pollution performance: Place the product after cyclic oil absorption on a 10° angle platform. See Figures 12-17 As shown, first, the product still has good superhydrophobicity after five cycles of oil absorption, indicating that it can be recycled and has a high reuse rate. Second, after five cycles of oil absorption, the product still maintains good stability, anti - pollution ability, and wear - resistance and other characteristics.

[0118] It should be noted that all the reagents used in the above examples are of analytical purity.

[0119] IV. See Figure 18 and Figure 19 for the oil - water separation application of the polymer / cotton fiber composite superhydrophobic / superoleophilic material

[0120] See specifically Figure 18 for the anti-wetting and light oil absorption performance test. The specific steps are as follows:

[0121] K1. Add deionized water to the container until the entire container is filled;

[0122] K2. See Figure 18 and suck up a drop of peanut oil dyed with oil-soluble blue dye, and drop it in the center of the container filled with deionized water;

[0123] K3. Clamp a polymer / cotton fiber composite superhydrophobic / superoleophilic material in the center of the container to suck up the dyed peanut oil until the dyed peanut oil is completely sucked up;

[0124] K4. Take out the polymer / cotton fiber composite superhydrophobic / superoleophilic material that has sucked up the dyed peanut oil and observe the wetting state of its surface.

[0125] The anti-wetting and heavy oil absorption performance test is also carried out. The specific steps are as follows:

[0126] E1. Add deionized water to the container;

[0127] E2. See Figure 19 and suck up dichloromethane dyed with oil-soluble red dye, insert it underwater, and squeeze out a drop;

[0128] E3. Clamp a polymer / cotton fiber composite superhydrophobic / superoleophilic material and slowly extend it to the bottom of the container to suck up the dyed dichloromethane until the dyed dichloromethane is completely absorbed by the product;

[0129] E4. Take out the dyed polymer / cotton fiber composite superhydrophobic / superoleophilic material from the container and observe the wetting state of the product surface.

[0130] The results are as Figure 18 shown. The surface of the polymer / cotton fiber composite superhydrophobic / superoleophilic material that has sucked up the peanut oil dyed with oil-soluble blue dye still remains in a good dry state;

[0131] As Figure 19 shown, during the process of putting the polymer / cotton fiber composite superhydrophobic / superoleophilic material into the container to suck up dichloromethane dyed with oil-soluble red, there is an obvious air layer between the polymer / cotton fiber composite superhydrophobic / superoleophilic material and deionized water, and the surface still remains in a good dry state when taken out of the container later. In summary, this product has good anti-wetting and oil absorption performance and can be widely applied in the field of oil-water separation.

[0132] All the reagents used in this example are of analytical purity.

Claims

1. Preparation method of polymer / cotton fiber composite-based superhydrophobic / superoleophilic material, characterized in that It includes the following steps: Weigh dipentaerythritol penta- / hexa-acrylate, and completely dissolve the dipentaerythritol penta- / hexa-acrylate in absolute ethanol; add hexafluorobutyl methacrylate and mix evenly; add divinylbenzene to make it fully dissolved; add azobisisobutyronitrile to make it fully dissolved; add raw cotton to make the raw cotton evenly dispersed in the reaction liquid phase; add ethylenediamine-terminated polyethyleneimine to make it fully dissolved and ensure that the raw cotton is evenly dispersed in the reaction liquid phase, then let it stand. After the reaction is completed, a polymer / cotton fiber composite gel system is formed; place the polymer / cotton fiber composite gel system product in a high-temperature environment for in-situ polymerization reaction to obtain a polymer / cotton fiber composite-based superhydrophobic / superoleophilic material.

2. The preparation method of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material according to claim 1, characterized in that: The mass ratio of the hexafluorobutyl methacrylate to the dipentaerythritol penta- / hexa-acrylate is 33-67:

100.

3. The preparation method of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material according to claim 1, characterized in that: The mass ratio of the divinylbenzene to the dipentaerythritol penta- / hexa-acrylate is 6-33:

100.

4. The preparation method of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material according to claim 1, characterized in that: The mass ratio of the azobisisobutyronitrile to the dipentaerythritol penta- / hexa-acrylate is 6:

100.

5. The preparation method of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material according to claim 1, characterized in that: The raw cotton is Xinjiang upland cotton, and the mass ratio of the raw cotton to the dipentaerythritol penta- / hexa-acrylate is 2.6:

100.

6. The preparation method of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material according to claim 1, characterized in that: The mass ratio of the ethylenediamine-terminated polyethyleneimine to the dipentaerythritol penta- / hexa-acrylate is 13-20:

100.

7. The preparation method of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material according to claim 1, characterized in that: When adding the ethylenediamine-terminated polyethyleneimine, control the reaction temperature at room temperature and the reaction time at 12 h.

8. The preparation method of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material according to claim 1, characterized in that: Control the reaction temperature for the in-situ polymerization reaction at 80 °C and the reaction time at 4 h.

9. Polymer / cotton fiber composite-based superhydrophobic / superoleophilic material, characterized in that: It is prepared by using the preparation method of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material described in any one of claims 1-8.

10. The use of the polymer / cotton fiber composite-based superhydrophobic / superoleophilic material according to claim 9, characterized in that, The polymer / cotton fiber composite-based superhydrophobic / superoleophilic material is applied to oil-water separation.

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