Preparation method of super-hydrophobic ultraviolet blocking fluorescent transparent wood

Abstract

The application discloses a preparation method of super-hydrophobic ultraviolet blocking fluorescent transparent wood, which comprises a wood template, carbon quantum dots and resin. The dried wood is soaked in a delignification mixed solution, and then subjected to subsequent steps such as dehydration to prepare a partially delignified wood template. The delignified wood template is immersed in a carbon quantum dot solution with different fluorescent properties, vacuum dried, immersed in resin, solidified and dried to obtain a multi-color fluorescent transparent wood. The surface of the fluorescent transparent wood is sprayed with a wet gel, and then dried to obtain the super-hydrophobic ultraviolet blocking fluorescent transparent wood. The preparation method of the super-hydrophobic ultraviolet blocking fluorescent transparent wood has the advantages of environmental friendliness, photoluminescence, heat preservation and heat insulation, and can endow the transparent wood with strong ultraviolet blocking ability and super-hydrophobic performance, thereby providing new theoretical and technical support for the research of new multifunctional wood-based composite materials and having a very wide application prospect.

Description

Technical Field

[0001] This invention relates to the field of novel wood technology, and in particular to a method for preparing superhydrophobic ultraviolet-blocking fluorescent transparent wood. Background Technology

[0002] Wood is a natural, environmentally friendly, and ubiquitous resource. Developing and processing wood-derived materials meets the needs of sustainable development. Furthermore, wood has applications in many fields due to its unique porous structure, renewability, ease of processing, and aesthetic appeal. In addition, wood can be functionalized through various methods, and with good design, many new properties can be introduced while retaining its original advantages, thereby significantly increasing its added value.

[0003] Transparent wood is a prime example of functionalized wood, possessing excellent mechanical toughness, shatter resistance, low thermal conductivity, and good light transmittance. It is primarily prepared by designing the structure of the wood cell walls and impregnating polymers with matching refractive indices.

[0004] Carbon quantum dots are a novel class of photoluminescent materials with excellent biocompatibility, high chemical stability, good water solubility, and multicolor optical properties, attracting attention in applications such as fluorescence sensing, photocatalysis, electrocatalysis, optoelectronic devices, and drug delivery. However, the UV blocking performance of fluorescent transparent wood composed of carbon quantum dots lacks evaluation, and its wetting properties are insufficient for some application scenarios.

[0005] Therefore, in order to solve the above problems, a method for preparing superhydrophobic ultraviolet-blocking fluorescent transparent wood is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide a method for preparing superhydrophobic ultraviolet-blocking fluorescent transparent wood, which endows the transparent wood with strong ultraviolet blocking ability and superhydrophobic properties, and has the advantages of being environmentally friendly, photoluminescent, and heat-insulating. This provides new theoretical and technical support for the research of novel multifunctional wood-based composite materials and has a very broad application prospect.

[0007] To achieve the above objectives, this invention provides a method for preparing superhydrophobic ultraviolet-blocking fluorescent transparent wood, the specific steps of which are as follows:

[0008] (1) Cut the wood sample longitudinally into appropriate thicknesses and dry it at 70-90℃ for 10 hours until it is completely dry, and set it aside for later use;

[0009] (2) Sodium hydroxide, disodium ethylenediaminetetraacetate and deionized water are mixed and stirred evenly to prepare a partially delignified aqueous solution. The wood sample dried in step (1) is soaked in the solution and pretreated at 70-80℃ for 10-20 min. Then magnesium sulfate and hydrogen peroxide are added and the wood sample is heated at 70-80℃ for 3-6 h for partial delignification treatment until the wood sample turns white.

[0010] (3) Take out the wood sample that has undergone partial delignification treatment in step (2), rinse it with deionized water to remove residual chemicals, and then store it in anhydrous ethanol for dehydration treatment to obtain partially delignified wood template.

[0011] (4) Weigh chitosan and add it to glacial acetic acid solution and mix evenly. Place it in a reaction vessel lined with polytetrafluoroethylene and heat it in an oven at 170-190℃ for 11-12 hours. Take out the mixed solution in the reaction vessel and place it in a centrifuge for solid-liquid separation. Filter the supernatant obtained by centrifugation through a filter membrane to remove insoluble substances. Then, use a dialysis bag to dialyze the filtered solution. Freeze-dry the dialysate to obtain powder and redissolve it in anhydrous ethanol to prepare carbon quantum dot impregnation solution A with blue fluorescence.

[0012] Chitosan was weighed and dispersed evenly in phosphoric acid. The mixture was placed in a reaction vessel lined with polytetrafluoroethylene and heated in an oven at 170-190℃ for 6-8 hours. The mixed solution in the reaction vessel was filtered through a filter membrane to remove insoluble substances. The filtered solution was dialyzed, and the dialysate was freeze-dried to obtain powder. The powder was then redissolved in anhydrous ethanol to prepare carbon quantum dot impregnation solution B with yellow fluorescence.

[0013] Weigh o-phenylenediamine and add it to sulfuric acid. Mix well and place it in a reaction vessel lined with polytetrafluoroethylene. Heat in an oven at 180-220℃ for 4-6 hours. Filter the mixed solution in the reaction vessel through a filter membrane to remove insoluble substances. Dialyze the filtered solution and freeze-dry the dialysate to obtain powder. Redissolve the powder in anhydrous ethanol to obtain carbon quantum dot impregnation solution C with red fluorescence.

[0014] (5) The partially delignified wood templates obtained in step (3) are respectively immersed in carbon quantum dot impregnation solution A, carbon quantum dot impregnation solution B and carbon quantum dot impregnation solution C prepared in step (4), and placed in a vacuum drying oven for 0.5-1.5h.

[0015] (6) Take out the partially delignified wood template impregnated with carbon quantum dot impregnation liquid obtained in step (5), re-impregnate it in resin, and perform vacuum negative pressure treatment. Take out the impregnated wood and place it in an oven at 60-80℃ to cure and dry to obtain multicolor fluorescent transparent wood.

[0016] (7) Mix methanol, methyltrimethoxysilane and oxalic acid and stir evenly. Add ammonia and deionized water dropwise. Continue stirring evenly and let stand at room temperature for 36-48 hours to obtain wet gel.

[0017] (8) Disperse the wet gel obtained in step (7) in a methanol solution, spray the dispersion onto the surface of fluorescent transparent wood with a spray gun, and then dry the fluorescent transparent wood in an oven at 60-70℃ to obtain superhydrophobic UV-blocking fluorescent transparent wood.

[0018] Preferably, in step (1), the wood sample is either balsa wood or birch, and the thickness is 0.4 to 1 mm.

[0019] Preferably, in step (2), the volume ratio of the wood sample to the partially delignified aqueous solution is (1-4):(5-8), and the concentration of sodium hydroxide aqueous solution in the partially delignified aqueous solution is 3wt%, the concentration of disodium ethylenediaminetetraacetate aqueous solution is 0.1wt%, the concentration of magnesium sulfate aqueous solution is 0.1wt%, and the concentration of hydrogen peroxide aqueous solution is 4wt%.

[0020] Preferably, in step (4), the solid-liquid ratio of the chitosan to the glacial acetic acid solution is (1-4):(200-400), and the concentration of the glacial acetic acid solution is 1 wt%.

[0021] Preferably, in step (4), the solid-liquid ratio of the chitosan to the phosphoric acid solution is (1-4):(100-200), and the concentration of the phosphoric acid solution is 20wt%.

[0022] Preferably, in step (4), the solid-liquid ratio of the o-phenylenediamine to the sulfuric acid solution is (1-4):(100-200), and the concentration of the sulfuric acid solution is 20 wt%.

[0023] Preferably, in step (4), the solid-liquid separation treatment conditions are a centrifugation speed of 8000-10000 r / min and a centrifugation time of 10-15 min, the dialysis treatment uses a dialysis bag with a molecular weight cutoff of 1000 Da and a dialysis time of 48-72 h, and the mass-volume ratio of the powder to anhydrous ethanol is (1-3):(100-200).

[0024] Preferably, in step (6), the resin is polyvinyl alcohol and epoxy resin AB glue, the concentration of polyvinyl alcohol is 5 to 10 wt%, the mass ratio of epoxy resin AB glue is (5:2) to (3:1), and the vacuum negative pressure treatment condition is 0.05 MPa.

[0025] Preferably, in step (7), the volume ratio of methanol, methyltrimethoxysilane and oxalic acid is (330-340):(65-70):(34-37), and the volume ratio of ammonia water to deionized water is (12-16):(3-9).

[0026] Preferably, in step (8), the solid-liquid ratio of the wet gel to methanol is (1-2):(10-25).

[0027] The advantages and positive effects of the preparation method of the superhydrophobic ultraviolet-blocking fluorescent transparent wood described in this invention are as follows:

[0028] 1. This invention uses chitosan and o-phenylenediamine as carbon sources to prepare multicolor carbon quantum dots that emit blue, yellow, and red light, and disperses them in partially delignified wood. Finally, resin encapsulation is used to achieve solid-state luminescence of carbon quantum dots through wood, giving the wood excellent ultraviolet light blocking ability and good fluorescence properties. It also improves the transmittance and haze of visible light, and effectively solves the problem of transparent wood easily oxidizing and yellowing in the air.

[0029] 2. This invention modifies fluorescent transparent wood to make its surface wettability superhydrophobic (static contact angle with water greater than 150°), which has a good waterproof effect and enhances the environmental adaptability of fluorescent transparent wood. It can be used as an assembly element in the production of green decoration, lighting, sensors and other products.

[0030] 3. The superhydrophobic ultraviolet-blocking fluorescent transparent wood prepared by this invention can rapidly heat up its surface when exposed to sunlight in a relatively cold environment and transfer the heat to the internal environment, thereby causing the internal temperature to rise rapidly. After the sunlight is removed, it can maintain the temperature for a period of time and can be used as a building material with thermal insulation function.

[0031] 4. The superhydrophobic ultraviolet-blocking fluorescent transparent wood prepared by this invention has better mechanical properties than transparent wood without carbon quantum dots, with the addition of carbon quantum dots. It has better compressive strength, bending strength and shock resistance, and is not easy to break. Moreover, its haze characteristics can avoid strong glare, which meets the needs of light-transmitting windows. It has many potential applications in the fields of construction, furniture, automobiles, and aircraft.

[0032] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0033] Figure 1 This is a flowchart of the preparation method of the superhydrophobic ultraviolet-blocking fluorescent transparent wood of the present invention;

[0034] Figure 2Transparency images of the superhydrophobic ultraviolet-blocking fluorescent transparent wood prepared according to the present invention are shown in (a) for unobstructed transparency, (b) for blue light transparent wood, (c) for yellow light transparent wood, and (d) for red light transparent wood.

[0035] Figure 3 The following are water contact angle diagrams of wood samples during the preparation of superhydrophobic ultraviolet-blocking fluorescent transparent wood in this invention: (a) is the water contact angle diagram of the original wood, (b) is the water contact angle diagram of the partially delignified wood template, (c) is the water contact angle diagram of blue light transparent wood, (d) is the water contact angle diagram of superhydrophobic blue light transparent wood, (e) is the water contact angle diagram of yellow light transparent wood, (f) is the water contact angle diagram of superhydrophobic yellow light transparent wood, (g) is the water contact angle diagram of red light transparent wood, and (h) is the water contact angle diagram of superhydrophobic red light transparent wood.

[0036] Figure 4 The images shown are scanning electron microscope (SEM) images of wood samples prepared from balsa wood using balsa wood as the wood sample in this invention. (a) is a scanning electron microscope image of the original balsa wood, (b) is a scanning electron microscope image of the fully delignified wood template, (c) is a scanning electron microscope image of the partially delignified wood template, (d) is a scanning electron microscope image of the transparent wood, (e) is a scanning electron microscope image of the yellow light transparent wood, (e1) is a magnified view of the inner frame of e, (f) is a scanning electron microscope image of the red light transparent wood, and (f1) is a magnified view of the inner frame of f.

[0037] Figure 5 These are scanning electron microscope (SEM) images of wood samples at various stages in the preparation of superhydrophobic ultraviolet-blocking fluorescent transparent wood using birch as the wood sample in this invention. (a, a1, a2) are SEM images of the original birch cross section gradually magnified; (b, b1, b2) are SEM images of the original birch longitudinal section gradually magnified; (c, c1, c2) are SEM images of the blue light transparent wood cross section gradually magnified; and (d, d1, d2) are SEM images of the blue light transparent wood longitudinal section gradually magnified.

[0038] Figure 6 The following are demonstration diagrams of the thermal insulation performance of superhydrophobic ultraviolet-blocking fluorescent transparent wood prepared by the present invention using balsa wood as a wood sample: (a) is a schematic diagram of the self-made hot box, (b) is an infrared thermal image under a certain solar intensity, (c) is a heating curve, and (d) is a cooling curve. Detailed Implementation

[0039] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0040] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0041] Example 1

[0042] A method for preparing superhydrophobic, ultraviolet-blocking, fluorescent transparent wood, the specific steps of which are as follows:

[0043] (1) Cut birch wood samples with a thickness of 0.4 mm longitudinally and dry them at 75℃ for 10 hours until they are completely dry for later use.

[0044] (2) The wood dried in step (1) was immersed in an aqueous solution of sodium hydroxide (3wt%) and disodium ethylenediaminetetraacetate (0.1wt%), with a volume ratio of wood sample to aqueous solution of 2:5. The wood was heated at 70°C for 10 min, and then magnesium sulfate (0.1wt%) and hydrogen peroxide (4.0wt%) were added and the wood was heated at 70°C for 6 h until the wood turned completely white to obtain partially delignified wood.

[0045] (3) Take out the wood sample that has undergone partial delignification in step (2), rinse it with deionized water and store it in anhydrous ethanol for dehydration treatment to obtain partially delignified wood template.

[0046] (4) Weigh 0.5g of chitosan and stir for 48h to dissolve it in glacial acetic acid solution (100mL, 1wt%). Place it in a reaction vessel lined with polytetrafluoroethylene and heat it in an oven to 180℃ for 12h. After cooling to room temperature, centrifuge the solution after reaction at 10000r / min for 15min to separate solid and liquid. Then filter the supernatant through a 0.22μm filter membrane to remove insoluble substances. Then dialyze the filtered liquid with a dialysis bag (1000Da) for 48h. After freeze-drying the obtained dialysate, obtain powder. Take 0.02g of freeze-dried powder and dissolve it in 20mL of anhydrous ethanol to prepare carbon quantum dot impregnation solution A with blue fluorescence.

[0047] (5) The partially delignified wood template obtained in step (3) is immersed in the impregnation solution A prepared in step (4) and placed in a vacuum drying oven for 1 hour.

[0048] (6) Take out the partially delignified wood impregnated with carbon quantum dot impregnation solution A obtained in step (5), re-impregnate it in 10 mL of 10 wt% polyvinyl alcohol aqueous solution, and repeatedly treat it 4 times under vacuum negative pressure of 0.05 MPa for 30 min each time. Then, cure and dry the impregnated wood in an oven at 60 °C to obtain ultraviolet-blocking fluorescent transparent wood.

[0049] (7) Methanol (67.2 mL), methyltrimethoxysilane (13.62 mL) and oxalic acid (7.1 mL) were added to an Erlenmeyer flask at room temperature and stirred magnetically for 24 h. Ammonia (7.3 mL) and deionized water (2.5 mL) were added dropwise. After stirring magnetically for 15 min, the mixture was allowed to stand at room temperature for 48 h to obtain a wet gel.

[0050] (8) Take 5g of wet gel into a beaker, add methanol (50mL), and sonicate for 3min to obtain an alcohol gel dispersion. Spray the dispersion onto the surface of UV-blocking fluorescent transparent wood with a spray gun, and then dry it in a 60℃ oven to obtain superhydrophobic UV-blocking fluorescent transparent wood.

[0051] Example 2

[0052] A method for preparing superhydrophobic, ultraviolet-blocking, fluorescent transparent wood, the specific steps of which are as follows:

[0053] (1) Cut out a 1 mm thick sample of balsa wood longitudinally and dry it at 75℃ for 10 h until it is completely dry for later use.

[0054] (2) The dried wood from step (1) was immersed in an aqueous solution of sodium hydroxide (3 wt%) and disodium ethylenediaminetetraacetate (0.1 wt%), with a volume ratio of wood sample to aqueous solution of 2:5, and heated at 70°C for 10 min. Subsequently, magnesium sulfate (0.1 wt%) and hydrogen peroxide (4.0 wt%) were added, and the mixture was further heated at 70°C for 6 h until the wood turned completely white to obtain partially delignified wood;

[0055] (3) Take out the wood sample that has undergone partial delignification in step (2), rinse it with deionized water and store it in anhydrous ethanol for dehydration treatment to obtain partially delignified wood template.

[0056] (4) Weigh 0.2g of chitosan, and disperse it evenly in 20mL of phosphoric acid (20%) solution by mixing, stirring and ultrasonic treatment for 5min. Then transfer the mixture to a polytetrafluoroethylene-lined reactor and place it in an oven at 180℃ for 6h. After cooling to room temperature, filter the obtained liquid through a 0.22mm filter membrane to remove larger particles. Then dialyze the filtered liquid with a 1000Da dialysis bag for 24h. After freeze-drying the obtained dialysate, obtain powder. Take 0.02g of freeze-dried powder and dissolve it in 20mL of anhydrous ethanol to prepare carbon quantum dot impregnation solution B with yellow fluorescence.

[0057] (5) The partially delignified wood template obtained in step (3) is immersed in the impregnation solution B prepared in step (4) and placed in a vacuum drying oven for 1 hour;

[0058] (6) Take out the partially delignified wood impregnated with carbon quantum dot impregnation solution B obtained in step (5), re-impregnate it in 10 mL of epoxy resin AB glue prepared at a volume ratio of 1:3, and repeatedly treat it under vacuum negative pressure of 0.05 MPa 4 times, 30 min each time. Then, cure and dry the impregnated wood in an oven at 60℃ to obtain ultraviolet blocking fluorescent transparent wood.

[0059] (7) Methanol (67.2 mL), methyltrimethoxysilane (13.62 mL) and oxalic acid (7.1 mL) were added to an Erlenmeyer flask at room temperature and stirred magnetically for 24 h. Ammonia (7.3 mL) and deionized water (2.5 mL) were added dropwise. After stirring magnetically for 15 min, the mixture was allowed to stand at room temperature for 48 h to obtain a wet gel.

[0060] (8) Take 5g of wet gel into a beaker, add methanol (50mL), and sonicate for 3min to obtain alcohol gel dispersion; spray the dispersion onto the surface of UV-blocking fluorescent transparent wood with a spray gun, and dry it in a 60℃ oven to obtain superhydrophobic UV-blocking fluorescent transparent wood.

[0061] Example 3

[0062] A method for preparing superhydrophobic, ultraviolet-blocking, fluorescent transparent wood, the specific steps of which are as follows:

[0063] (1) Cut out a 1 mm thick sample of balsa wood longitudinally and dry it at 75℃ for 10 h until it is completely dry for later use.

[0064] (2) The wood dried in step (1) was immersed in an aqueous solution of sodium hydroxide (3wt%) and disodium ethylenediaminetetraacetate (0.1wt%), with a volume ratio of wood sample to aqueous solution of 2:5. The wood was heated at 70°C for 10 min, and then magnesium sulfate (0.1wt%) and hydrogen peroxide (4.0wt%) were added. The wood was then heated at 70°C for 6 h until it turned completely white to obtain partially delignified wood.

[0065] (3) Take out the wood sample that has undergone partial delignification in step (2), rinse it with deionized water and store it in anhydrous ethanol for dehydration treatment to obtain partially delignified wood template.

[0066] (4) Weigh 108 mg of o-phenylenediamine and dissolve it in 10 mL of sulfuric acid solution (20%). After stirring the mixture evenly, transfer it to a high-pressure reactor lined with polytetrafluoroethylene and place it in an oven at 200 °C for 5 h. After cooling to room temperature, filter the solution obtained from the reaction using a 0.22 mm filter membrane to remove insoluble substances and relatively large particles. Then dialyze the filtered liquid with a 1000 Da dialysis bag for 48 h. After freeze-drying the obtained dialysate, obtain powder. Take 0.02 g of the freeze-dried powder and dissolve it in 20 mL of anhydrous ethanol to prepare carbon quantum dot impregnation solution C with red fluorescence.

[0067] (5) The partially delignified wood template obtained in step (3) is immersed in the impregnation solution C prepared in step (4) and placed in a vacuum drying oven for 1 hour;

[0068] (6) Take out the partially delignified wood impregnated with carbon quantum dot impregnation liquid C obtained in step (5), re-impregnate it in 10 mL of epoxy resin AB glue prepared at a volume ratio of 1:3, and repeatedly treat it under vacuum negative pressure of 0.05 MPa for 4 times, each time for 30 min. Then, cure and dry the impregnated wood in an oven at 60°C to obtain ultraviolet blocking fluorescent transparent wood.

[0069] (7) Methanol (67.2 mL), methyltrimethoxysilane (13.62 mL) and oxalic acid (7.1 mL) were added to an Erlenmeyer flask at room temperature and stirred magnetically for 24 h. Ammonia (7.3 mL) and deionized water (2.5 mL) were added dropwise. After stirring magnetically for 15 min, the mixture was allowed to stand at room temperature for 48 h to obtain a wet gel.

[0070] (8) Take 5g of wet gel into a beaker, add methanol (50mL), and sonicate for 3min to obtain alcohol gel dispersion; spray the dispersion onto the surface of UV-blocking fluorescent transparent wood with a spray gun, and dry it in a 60℃ oven to obtain superhydrophobic UV-blocking fluorescent transparent wood.

[0071] Test case

[0072] The performance of the superhydrophobic UV-blocking fluorescent transparent wood prepared in Examples 1-3 was tested respectively, and the test results are shown in Table 1.

[0073] Table 1 Performance Test Results

[0074]

[0075]

[0076] The superhydrophobic, UV-blocking, fluorescent transparent wood produced by this invention exhibits optical transmittance exceeding 69% and haze within the range of 70-80%. Upon UV excitation, it emits fluorescence of different colors, achieving a blocking rate of over 80% for 365nm UV light and over 69% for both 280-320nm and 320-400nm UV light. After hydrophobic modification, the contact angle approaches 144° or higher. The carbon quantum dots exhibit stable quantum fluorescence properties and excellent UV blocking and photothermal conversion effects. The wood's layered structure is well-preserved, the process is simple and environmentally friendly, and the resulting material is lightweight with significantly improved mechanical properties compared to raw wood and pure resin.

[0077] Therefore, the present invention adopts the above-mentioned method for preparing superhydrophobic ultraviolet-blocking fluorescent transparent wood, which endows the transparent wood with strong ultraviolet blocking ability and superhydrophobic properties, and has the advantages of environmental friendliness, photoluminescence, and thermal insulation. It provides new theoretical and technical support for the research of novel multifunctional wood-based composite materials and has a very broad application prospect.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing superhydrophobic ultraviolet-blocking fluorescent transparent wood, characterized in that, The specific steps are as follows: (1) Cut balsa wood or birch wood longitudinally into pieces with a thickness of 0.4-1 mm, and dry them at 70-90℃ for 10 hours until they are completely dry, and set aside for later use; (2) Sodium hydroxide, disodium ethylenediaminetetraacetate, and deionized water are mixed and stirred evenly to prepare a partially delignified aqueous solution. The wood sample dried in step (1) is immersed in the solution and pretreated at 70-80℃ for 10-20 min. Then magnesium sulfate and hydrogen peroxide are added and the solution is heated at 70-80℃ for 3-6 h for partial delignification treatment until the wood sample turns white. The concentration of sodium hydroxide aqueous solution in the partially delignified aqueous solution is 3 wt%, the concentration of disodium ethylenediaminetetraacetate aqueous solution is 0.1 wt%, the concentration of magnesium sulfate aqueous solution is 0.1 wt%, and the concentration of hydrogen peroxide aqueous solution is 4 wt%. (3) Take out the wood sample that has undergone partial delignification treatment in step (2), rinse it with deionized water to remove residual chemicals, and then store it in anhydrous ethanol for dehydration treatment to obtain partially delignified wood template. (4) Weigh chitosan and add it to 20wt% phosphoric acid and disperse it evenly. Place it in a reaction vessel lined with polytetrafluoroethylene and heat it in an oven at 170-190℃ for 6-8 hours. Filter the mixed solution in the reaction vessel through a filter membrane to remove insoluble substances. Dialyze the filtered solution and freeze-dry the dialysate to obtain powder. Redissolve the powder in anhydrous ethanol to obtain carbon quantum dot impregnation solution B with yellow fluorescence. Weigh o-phenylenediamine and add it to 20wt% sulfuric acid and mix well. Place the mixture in a reaction vessel lined with polytetrafluoroethylene and heat it in an oven at 180-220℃ for 4-6 hours. Filter the mixed solution in the reaction vessel through a filter membrane to remove insoluble substances. Dialyze the filtered solution and freeze-dry the dialysate to obtain a powder. Redissolve the powder in anhydrous ethanol to obtain carbon quantum dot impregnation solution C with red fluorescence. (5) The partially delignified wood templates obtained in step (3) are respectively immersed in carbon quantum dot impregnation solution B and carbon quantum dot impregnation solution C prepared in step (4), and placed in a vacuum drying oven for 0.5-1.5h. (6) Take out the partially delignified wood template impregnated with carbon quantum dot impregnation solution obtained in step (5), and re-impregnate it in resin, which is polyvinyl alcohol and epoxy resin AB glue, and perform vacuum negative pressure treatment at 0.05MPa. Take out the impregnated wood and place it in an oven at 60-80℃ for curing and drying to obtain multi-color fluorescent transparent wood; the concentration of polyvinyl alcohol is 5-10wt%, and the mass ratio of epoxy resin AB glue is 5:2-3:

1. (7) Mix methanol, methyltrimethoxysilane and oxalic acid and stir evenly. Add ammonia and deionized water dropwise. Continue stirring evenly and let stand at room temperature for 36-48 hours to obtain wet gel. (8) Disperse the wet gel obtained in step (7) in a methanol solution, spray the dispersion onto the surface of fluorescent transparent wood with a spray gun, and then dry the fluorescent transparent wood in an oven at 60-70℃ to obtain superhydrophobic UV-blocking fluorescent transparent wood.

2. The method for preparing a superhydrophobic ultraviolet-blocking fluorescent transparent wood according to claim 1, characterized in that: In step (2), the volume ratio of the wood sample to the partial delignification aqueous solution is 1-4:5-8.

3. The method for preparing a superhydrophobic ultraviolet-blocking fluorescent transparent wood according to claim 1, characterized in that: In step (4), the solid-liquid ratio of chitosan to phosphoric acid solution is 1-4:100-200.

4. The method for preparing a superhydrophobic ultraviolet-blocking fluorescent transparent wood according to claim 1, characterized in that: In step (4), the solid-liquid ratio of the o-phenylenediamine to the sulfuric acid solution is 1-4:100-200.

5. The method for preparing a superhydrophobic ultraviolet-blocking fluorescent transparent wood according to claim 1, characterized in that: In step (4), the dialysis treatment uses a dialysis bag with a molecular weight cutoff of 1000 Da, the dialysis time is 48-72 h, and the mass-volume ratio of the powder to anhydrous ethanol is 1-3:100-200.

6. The method for preparing a superhydrophobic ultraviolet-blocking fluorescent transparent wood according to claim 1, characterized in that: In step (7), the volume ratio of methanol, methyltrimethoxysilane and oxalic acid is 330-340:65-70:34-37, and the volume ratio of ammonia water to deionized water is 12-16:3-9.

7. The method for preparing a superhydrophobic ultraviolet-blocking fluorescent transparent wood according to claim 1, characterized in that: In step (8), the solid-liquid ratio of the wet gel to methanol is 1-2:10-25.

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