Preparation method and application of hydrogel coating constructed based on shell powder

Abstract

The invention discloses a preparation method and application of a hydrogel coating constructed based on shell powder, the preparation method comprises the following steps: S1, uniformly mixing shell powder, polyvinyl alcohol and water to obtain a mixed solution, coating the surface of a base material with the mixed solution, then spraying a tannic acid solution to the surface of the base material, and then drying to obtain a modified base material; s2, the modified base material obtained in the step S1 is immersed in a precursor solution for a reaction, and a hydrogel coating can be prepared on the surface of the base material; the precursor solution is prepared from glucolactone, sodium alginate and water. The raw materials used in the preparation method are environment-friendly and free of post-treatment process requirements, the reaction conditions are mild, the precursor solution does not need to be filled with nitrogen, the preparation method is suitable for base materials of various materials and shapes, and the thickness of the prepared hydrogel coating is controllable.

Description

Technical Field

[0001] This invention belongs to the field of hydrogel materials technology, specifically relating to a method for preparing a hydrogel coating based on shell powder and its application. Background Technology

[0002] Marine shellfish account for over 70% of global aquaculture production, but only 30%–40% of them are used in food production, while the remaining 60%–70% are discarded as waste or byproducts. Therefore, improving the utilization rate of shellfish waste is crucial for global sustainable development. The main chemical component of shellfish waste is calcium carbonate, which decomposes into calcium ions under acidic conditions. Typically, it is ground into shellfish powder. Shellfish powder is commonly used as a food additive for calcium supplementation. Furthermore, it can be used as a filler to improve the mechanical properties of polymer materials.

[0003] Currently, the preparation of hydrogel coatings is limited by monomers, substrates, substrate shape, and reaction conditions. Furthermore, polymers such as epoxy resins and poly(vinyl acetate) are often used to modify the surface of the substrate to prepare hydrogel coatings on the modified substrate. However, the volatile substances generated during the production and use of these polymers are environmentally and human-harmful. Therefore, there is an urgent need for new, green methods for preparing hydrogel coatings to meet market demands. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a method for preparing a hydrogel coating based on shell powder. The raw materials used in this preparation method are environmentally friendly, require no post-processing, the reaction conditions are mild, and there is no need to purge the precursor solution with nitrogen. It is suitable for substrates of various materials and shapes, and the thickness of the prepared hydrogel coating is controllable.

[0005] The present invention also proposes a hydrogel coating prepared by the above preparation method.

[0006] The present invention also proposes a coating product.

[0007] The present invention also proposes an application.

[0008] According to a first aspect of the present invention, a method for preparing a hydrogel coating based on shell powder is provided, the method comprising the following steps:

[0009] S1: Mix shell powder, polyvinyl alcohol and water to obtain a mixture, apply the mixture to the surface of the substrate, spray tannic acid solution onto the surface of the substrate, and then dry to obtain a modified substrate.

[0010] S2: The modified substrate obtained in step S1 is immersed in the precursor solution for reaction, and a hydrogel coating can be prepared on the surface of the substrate.

[0011] The precursor solution comprises gluconolactone, sodium alginate, and water.

[0012] In some embodiments of the present invention, the shell powder in step S1 is derived from at least one of oyster shells, clam shells, scallop shells and mussel shells.

[0013] In some embodiments of the present invention, the method for preparing the shell powder includes: putting waste shells into a crusher for grinding, and then putting the ground coarse product into an ultrasonic pulverizer for ultrasonic treatment to obtain shell powder.

[0014] In some embodiments of the present invention, the concentration of shell powder in the mixture is 1 to 20 mg / mL.

[0015] In some embodiments of the present invention, the concentration of shell powder in the mixture is 5 to 15 mg / mL.

[0016] In some embodiments of the present invention, the mass percentage of polyvinyl alcohol in the mixture is 5% to 10%.

[0017] In some embodiments of the present invention, the mass percentage of polyvinyl alcohol in the mixture is 6% to 8%.

[0018] In some embodiments of the present invention, the tannic acid solution in step S1 is an aqueous solution of tannic acid with a mass percentage of 10% to 30%.

[0019] In some embodiments of the present invention, the tannic acid solution in step S1 is an aqueous solution of tannic acid with a mass percentage of 15% to 25%.

[0020] In some embodiments of the present invention, the drying temperature in step S1 is 60°C to 80°C.

[0021] In some embodiments of the present invention, the drying temperature in step S1 is 65°C to 75°C.

[0022] In some embodiments of the present invention, the drying time in step S1 is 40 to 80 minutes.

[0023] In some embodiments of the present invention, the drying time in step S1 is 50 to 70 minutes.

[0024] In some embodiments of the present invention, the material of the substrate in step S1 is selected from at least one of plastic, metal, alloy and glass.

[0025] In some embodiments of the present invention, the concentration of gluconolactone in the precursor solution is 20–60 mg / mL.

[0026] In some embodiments of the present invention, the mass percentage of sodium alginate in the precursor solution is 1.5% to 2.5%.

[0027] In some embodiments of the present invention, the precursor solution in step S2 further includes acrylamide monomer, crosslinking agent and photoinitiator.

[0028] In some embodiments of the present invention, the precursor solution in step S2 further includes zwitterionic monomers.

[0029] In some embodiments of the present invention, the acrylamide monomer includes at least one of N-hydroxyethylacrylamide, N,N-dimethylacrylamide, acrylamide, and N-isopropylacrylamide.

[0030] In some embodiments of the present invention, the zwitterionic monomer includes sulfonated betaine methacrylate.

[0031] In some embodiments of the present invention, the concentration of acrylamide monomer in the precursor solution is 21.3 to 213 mg / mL.

[0032] In some embodiments of the present invention, the molar concentration of the N-isopropylacrylamide (NIPAM) monomer is 0.3 to 1 mol / L.

[0033] In some embodiments of the present invention, the molar concentration of the N-hydroxyethylacrylamide (HEAA) is 1 to 1.5 mol / L.

[0034] In some embodiments of the present invention, the molar concentration of N,N-dimethylacrylamide (DMAA) is 1 to 1.5 mol / L.

[0035] In some embodiments of the present invention, the molar concentration of the sulfonate betaine methacrylate (SBMA) is 1 to 1.5 mol / L.

[0036] In some embodiments of the present invention, the molar concentration of the acrylamide (AM) is 1 to 3 mol / L.

[0037] In some embodiments of the present invention, the crosslinking agent includes at least one selected from N,N-methylbisacrylamide, polyethylene glycol diacrylate, hexamethylenebisacrylamide, ethylene glycol diacrylate, and dipropylene glycol diacrylate.

[0038] In some embodiments of the present invention, the photoinitiator includes at least one selected from 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone, 1-hydroxy-cyclohexyl-phenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and 2,2'-azobisisobutylamidine dihydrochloride.

[0039] In some embodiments of the present invention, the concentration of the crosslinking agent in the precursor solution is 0.463 to 0.935 mg / mL.

[0040] In some embodiments of the present invention, the concentration of the photoinitiator in the precursor solution is 13.46 to 26.92 mg / mL.

[0041] In some embodiments of the present invention, the molar concentration of the crosslinking agent in the precursor solution is 0.1% to 0.2% of the molar concentration of the acrylamide monomer.

[0042] In some embodiments of the present invention, the molar concentration of the photoinitiator in the precursor solution is 2% to 4% of the molar concentration of the acrylamide monomer.

[0043] In some embodiments of the present invention, step S2 further includes: removing excess solution after the reaction and irradiating with an ultraviolet lamp.

[0044] In some embodiments of the present invention, the reaction time is 3 to 10 minutes.

[0045] In some embodiments of the present invention, the reaction time is 3 to 7 minutes.

[0046] In some embodiments of the present invention, the irradiation time of the ultraviolet lamp is 2 to 5 hours.

[0047] In some embodiments of the present invention, the wavelength of the ultraviolet lamp irradiation is 340–400 nm.

[0048] In some embodiments of the present invention, the power of the ultraviolet lamp irradiation is 5 to 100W.

[0049] According to a second aspect of the present invention, a hydrogel coating prepared by the preparation method described in the first aspect of the present invention is provided.

[0050] The shell powder in the hydrogel coating decomposes into calcium ions under the action of gluconolactone. The calcium ions undergo a complexation reaction with sodium alginate to form a first cross-linked network. Acrylamide monomer and zwitterionic monomer (sulfonate betaine methacrylate) form a second cross-linked network through free radical polymerization under the action of photoinitiator and cross-linking agent. The first and second cross-linked networks interpenetrate to form a green and universal dual-network hydrogel coating.

[0051] According to a third aspect of the present invention, a coating product is provided, the coating product comprising a substrate and a hydrogel coating coated on the surface of the substrate, the hydrogel coating being prepared by the preparation method described in the first aspect of the present invention.

[0052] According to a fourth aspect of the present invention, the application of the preparation method described in the first aspect of the present invention in the preparation of antifouling and / or lubricating products is proposed.

[0053] The present invention has at least the following beneficial effects:

[0054] (1) The method for preparing hydrogel coating provided by the present invention uses waste seashells to prepare hydrogel coating, which is in line with the concept of green environmental protection and achieves the purpose of turning waste into treasure;

[0055] (2) The tannic acid used in this invention can be extracted from grape skins, and sodium alginate can be extracted from algae. The sources are natural and environmentally friendly. Both gluconolactone and sodium alginate can be used as food additives. Polyvinyl alcohol is a non-toxic polymer raw material. It can be seen that the raw materials are environmentally friendly and do not require post-processing.

[0056] (3) The preparation method provided by the present invention can flexibly control the thickness of the hydrogel coating, thereby achieving the controllability of the coating;

[0057] (4) The preparation method provided by the present invention has mild reaction conditions and can be carried out in an open environment at room temperature. It does not require nitrogen filling of the precursor solution and is suitable for a variety of substrates and shapes.

[0058] (5) The hydrogel coating prepared by the present invention has excellent anti-fouling and lubrication properties, and can be practically applied to the production of anti-fouling / lubricating products. It has a wide range of applications and the preparation steps are simple. Attached Figure Description

[0059] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0060] Figure 1 The figures show the thickness test results of hydrogel coatings prepared on different substrates in the experimental examples of this invention;

[0061] Figure 2 The figures show the adhesion results of the hydrogel coating on substrates of different shapes in the experimental examples of this invention;

[0062] Figure 3 This is a cross-sectional SEM image of the hydrogel coating in the experimental example of this invention;

[0063] Figure 4 The image shows the test results of the lubrication performance of the hydrogel coating in the experimental examples of this invention;

[0064] Figure 5 The image shows the test results of the antifouling performance of the hydrogel coating in the experimental examples of this invention;

[0065] Figure 6 The graph shows the test results of the adhesion performance of the hydrogel coating in the experimental examples of this invention.

[0066] Figure 7 This is a graph showing the adhesion strength test results of the hydrogel coating in the experimental examples of this invention. Detailed Implementation

[0067] The following will clearly and completely describe the concept and technical effects of the present invention in conjunction with the embodiments to fully understand the purpose, features and effects of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0068] Example 1

[0069] This embodiment provides a method for preparing a hydrogel coating based on seashell powder, specifically including the following steps:

[0070] 1) By weight, 1 part of shell powder and 64.4 parts of water are mixed evenly and sonicated at 100W for 30 minutes. Then, 34.6 parts of a 20% polyvinyl alcohol aqueous solution are added (to make the final concentration of polyvinyl alcohol in the mixed solution 7wt%), and stirred evenly to obtain a mixed solution. 0.5 mL of the mixed solution is evenly coated onto the surface of a glass substrate (7.6 cm × 2.5 cm). Then, 1 mL of a 20wt% tannic acid aqueous solution is evenly sprayed onto the surface of the glass substrate. The substrate is then dried in a 70℃ oven for 60 minutes to obtain a modified substrate. The above method for preparing shell powder is as follows: waste scallop shells are ground into powder using a crusher, and then ultrasonically pulverized to obtain more uniformly dispersed shell powder with a particle size of 782 nm.

[0071] 2) Take 93.9 parts water, 3.8 parts gluconolactone, and 2.3 parts sodium alginate by weight, stir evenly to obtain a precursor solution; then immerse the modified substrate obtained in step 1) into the precursor solution and react at room temperature for 5 minutes. After 5 minutes, scrape off the excess solution on the modified substrate to prepare a hydrogel coating on the substrate surface.

[0072] Example 2

[0073] This embodiment provides a method for preparing a hydrogel coating based on shell powder. The only difference between this method and Example 1 is that the glass substrate is replaced with an acrylic substrate, while the other steps are the same as in Example 1.

[0074] Example 3

[0075] This embodiment provides a method for preparing a hydrogel coating based on shell powder. The only difference between this method and Example 1 is that the glass substrate is replaced with a polyethylene terephthalate (PET) substrate, while the other steps are the same as in Example 1.

[0076] Example 4

[0077] This embodiment provides a method for preparing a hydrogel coating based on shell powder. The only difference between this method and Example 1 is that the glass substrate is replaced with a polytetrafluoroethylene (PTFE) substrate, while the other steps are the same as in Example 1.

[0078] Example 5

[0079] This embodiment provides a method for preparing a hydrogel coating based on shell powder. The only difference between this method and Example 1 is that the glass substrate is replaced with a titanium substrate, while the other steps are the same as in Example 1.

[0080] Example 6

[0081] This embodiment provides a method for preparing a hydrogel coating based on shell powder. The only difference between this method and Example 1 is that the glass substrate is replaced with an iron substrate, while the other steps are the same as in Example 1.

[0082] Example 7

[0083] This embodiment provides a method for preparing a hydrogel coating based on seashell powder, specifically including the following steps:

[0084] 1) By weight, 1 part of shell powder and 65.03 parts of water are mixed evenly and sonicated at 100W for 30 minutes. Then, 34.97 parts of polyvinyl alcohol solution are added (to make the final concentration of polyvinyl alcohol in the mixed solution 7wt%), and stirred evenly to obtain a mixed solution. 0.5 mL of the mixed solution is evenly coated onto the surface of a glass substrate (7.6 cm × 2.5 cm). Then, 1 mL of 20wt% tannic acid solution is evenly sprayed onto the surface of the glass substrate. The substrate is then dried in a 70℃ oven for 60 minutes to obtain a modified substrate. The above-mentioned shell powder preparation method is as follows: waste scallop shells are ground into powder using a crusher, and then ultrasonically pulverized to obtain more uniformly dispersed shell powder with a particle size of 782 nm.

[0085] 2) By weight, take 77.4 parts water, 3.10 parts gluconolactone, 1.94 parts sodium alginate, 0.039 parts N,N-methylbisacrylamide, 1.04 parts 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone (IR2959), and 16.49 parts acrylamide and stir until homogeneous to obtain a precursor solution; then immerse the modified substrate obtained in step 1) in the precursor solution and react at room temperature for 5 minutes. After 5 minutes, scrape off the excess solution on the modified substrate; irradiate with a UV lamp at a wavelength of 365 nm and 18 W for 3 hours to prepare a hydrogel coating on the substrate surface.

[0086] Example 8

[0087] This embodiment provides a method for preparing a hydrogel coating based on shell powder. The only difference between this method and Example 7 is that the precursor solution formulation in step 2) is replaced with 81.83 parts water, 3.27 parts gluconolactone, 2.05 parts sodium alginate, 0.02 parts N,N-methylbisacrylamide, 0.55 parts 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone (IR2959), and 12.27 parts N,N-dimethylacrylamide (DMAA). All other steps are the same as in Example 1.

[0088] Example 9

[0089] This embodiment provides a method for preparing a hydrogel coating based on shell powder. The only difference between this method and Example 7 is that the precursor solution formulation in step 2) is replaced with 86.24 parts water, 3.45 parts gluconolactone, 2.16 parts sodium alginate, 0.011 parts N,N-methylbisacrylamide, 0.32 parts 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone (IR2959), and 7.81 parts N-isopropylacrylamide (NIPAM). All other steps are the same as in Example 1.

[0090] Example 10

[0091] This embodiment provides a method for preparing a hydrogel coating based on shell powder. The only difference between this method and Example 7 is that the precursor solution formulation in step 2) is replaced with 67.06 parts water, 2.68 parts gluconolactone, 1.68 parts sodium alginate, 0.017 parts N,N-methylbisacrylamide, 0.45 parts 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone (IR2959), and 28.11 parts sulfonated betaine methacrylate (SBMA). All other steps are the same as in Example 1.

[0092] Example 11

[0093] This embodiment provides a method for preparing a hydrogel coating based on shell powder. The only difference between this method and Example 7 is that the precursor solution formulation in step 2) is replaced with 80.35 parts water, 3.21 parts gluconolactone, 2.01 parts sodium alginate, 0.02 parts N,N-methylbisacrylamide, 0.54 parts 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone (IR2959), and 13.86 parts N-hydroxyethylacrylamide (HEAA). All other steps are the same as in Example 1.

[0094] Example 12

[0095] This embodiment provides a method for preparing a hydrogel coating based on shell powder. The only difference between this method and Example 7 is that the precursor solution formulation in step 2) is replaced with 77.4 parts water, 3.10 parts gluconolactone, 1.94 parts sodium alginate, 0.039 parts N,N-methylbisacrylamide, 1.04 parts 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone (IR2959), and 16.49 parts acrylamide (AM). All other steps are the same as in Example 1.

[0096] Comparative Example 1

[0097] This comparative example provides a method for preparing a hydrogel coating, specifically including the following steps:

[0098] 1) By weight, 65.03 parts of water and 34.97 parts of polyvinyl alcohol solution (to make the final concentration of polyvinyl alcohol in the mixed solution 7wt%) were stirred evenly to obtain a mixed solution; 0.5 mL of the mixed solution was evenly applied to the surface of a glass substrate (7.6 cm × 2.5 cm), and then 1 mL of 20 wt% tannic acid aqueous solution was sprayed on the surface of the glass substrate. Then, it was placed in a 70℃ oven and dried for 60 min to obtain a modified substrate.

[0099] 2) Take 93.9 parts water, 3.8 parts gluconolactone, and 2.3 parts sodium alginate by weight, stir evenly to obtain a precursor solution; then immerse the modified substrate obtained in step 1) into the precursor solution and react at room temperature for 5 minutes. After 5 minutes, scrape off the excess solution on the modified substrate.

[0100] Test example

[0101] This experiment tested various properties of the hydrogel coatings prepared in Examples 1-12 and Comparative Example 1. The specific experimental methods and results are as follows:

[0102] 1. The Influence of Different Substrate Materials on the Thickness of Hydrogel Coatings

[0103] The only difference between the hydrogel coatings based on shell powder provided in Examples 1-6 is that they were prepared on substrates of different materials. The thickness of the six groups of hydrogel coatings was measured using a polarizing microscope, and the results are as follows: Figure 1 As shown.

[0104] Depend on Figure 1 It is understood that the method for preparing hydrogel coatings based on shell powder provided by the present invention is universal and can generate hydrogel coatings in situ on the surfaces of glass, metal, alloy and plastic. The coating thickness ranges from 200μm to 536μm, and the thickness of the hydrogel coating can be adjusted by changing the material of the substrate.

[0105] 2. Evaluate the growth of hydrogel coatings on complex three-dimensional structural surfaces.

[0106] Based on the preparation method provided in Example 1, 0.005 g of Rhodamine B was added to the precursor solution in step 2) for visual staining. Medical catheters, threaded metal, and fan blades were selected as substrates. The staining of the substrates was observed, and the results are as follows: Figure 2 As shown.

[0107] Depend on Figure 2 It is known that the method for preparing hydrogel coating based on shell powder provided by the present invention can generate hydrogel coating in situ on the surface of three-dimensional objects including medical catheters, threaded metal and fan blades. The resulting hydrogel coating has a smooth and flat surface, and the coating can still be clearly observed on the threaded surface of the threaded metal, indicating that the hydrogel coating can grow on complex structural surfaces such as threads.

[0108] 3. Scanning electron microscopy (SEM) observation of the hydrogel coating

[0109] The microstructure of the hydrogel coating prepared in Example 7 was observed using scanning electron microscopy. The hydrogel coating prepared in Example 7 was extracted with liquid nitrogen, broken, and then freeze-dried for 12 hours. The cross-sectional micromorphology was observed using SEM, and the results are as follows. Figure 3 As shown.

[0110] Depend on Figure 3 It can be seen that the hydrogel coating generated in situ on the substrate surface adheres tightly to the substrate, indicating that there is a good bond between the hydrogel coating and the substrate.

[0111] 4. Evaluate the lubricity of the hydrogel coating.

[0112] Tilt a glass substrate at a 5° angle and place a 50g weight on its lifting side (see...). Figure 4 In (a) of the example, weights are adhered to the substrate surface. The lubricity of the coating is tested by sliding a weight onto the glass substrate after the hydrogel coating prepared in Example 7 is applied. The results are as follows: Figure 4 As shown in (b).

[0113] Depend on Figure 4 It can be seen that a 50g weight can slide off the surface of the hydrogel coating on the substrate, indicating that the hydrogel coating provided by the present invention has good lubrication ability.

[0114] 5. Evaluate the antifouling performance of the hydrogel coating.

[0115] Red pigment was dropped onto the surface of the hydrogel coating prepared in Example 7, and a blank glass was used as a blank control to test the antifouling performance of the hydrogel coating. The results are as follows. Figure 5 As shown.

[0116] Depend on Figure 5 It can be seen that when red pigment is dropped onto the surface of the hydrogel coating, shaken in water and then taken out, there is almost no pigment residue on the coating surface, while a large amount of red pen ink remains on the blank glass surface without coating. This indicates that the hydrogel coating prepared by the present invention has good anti-fouling ability.

[0117] 6. Investigate the role of shell powder in hydrogel coatings.

[0118] Comparative Example 1 differs from Example 1 only in that it omits the shell powder component; the final product obtained in Comparative Example 1 is as follows: Figure 6 As shown.

[0119] Depend on Figure 6 It can be seen that after omitting the key component of shell powder, the modified substrate does not form a hydrogel coating on its surface after reacting with the precursor solution, indicating that shell powder is an indispensable key component in the hydrogel coating provided by this invention.

[0120] 7. Evaluate the adhesion strength of the hydrogel.

[0121] The adhesion strength of the hydrogels prepared in Examples 8-12 to the substrate was tested using a 90° peel test. The adhesion strength of the hydrogels was characterized using an Instron 5565 electronic universal testing machine (USA) at a peel speed of 30 mm / min. The average load / width at a peel displacement of 10 mm-50 mm was used as the test result. A hydrogel coating was grown in situ on a substrate (76 mm × 25 mm × 1 mm) under UV light for 3 hours. With 15 minutes remaining in the irradiation time, the glass mold was opened, and a layer of gauze coated with the corresponding reaction solution was placed over the surface of the hydrogel in the mold. Irradiation continued for another 15 minutes. The gauze served as a backing in the 90° peel test. The test sample size was 76 mm × 25 mm. The control group, SA-Gel, was a single-network hydrogel coating prepared from sodium alginate, GDL, and water (i.e., Comparative Example 1). The results are as follows: Figure 7 As shown.

[0122] Depend on Figure 7 It can be seen that the adhesion of the single-network hydrogel coating SA-Gel in the control group is lower than that of the double-network hydrogel coating provided by the present invention. This is because the addition of acrylamide monomer and zwitterionic monomer generates a double-network hydrogel coating, which improves the mechanical properties of the coating. In addition, the adhesion of the double-network hydrogel coating prepared by AM is higher than that of the double-network hydrogel coating prepared by other second monomers. This is because the double-network hydrogel coating prepared by AM has good toughness, which improves the cohesion of the coating.

[0123] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A method for preparing a hydrogel coating based on seashell powder, characterized in that, The preparation method includes the following steps: S1: Mix shell powder, polyvinyl alcohol and water to obtain a mixture, apply the mixture to the surface of the substrate, spray tannic acid solution onto the surface of the substrate, and then dry to obtain a modified substrate. S2: The modified substrate obtained in step S1 is immersed in the precursor solution for reaction, and a hydrogel coating can be prepared on the surface of the substrate. The precursor solution comprises gluconolactone, sodium alginate, and water.

2. The preparation method according to claim 1, characterized in that, The shell powder mentioned in step S1 is derived from at least one of oyster shells, clam shells, scallop shells, and mussel shells; Preferably, the concentration of shell powder in the mixture is 1–20 mg / mL; Preferably, the mass percentage of polyvinyl alcohol in the mixture is 5% to 10%.

3. The preparation method according to claim 1, characterized in that, The tannic acid solution mentioned in step S1 is an aqueous solution of tannic acid with a mass percentage of 10% to 30%. Preferably, the drying temperature in step S1 is 60°C to 80°C; Preferably, the material of the substrate in step S1 is selected from at least one of plastic, metal, alloy and glass.

4. The preparation method according to claim 1, characterized in that, The concentration of gluconolactone in the precursor solution is 20–60 mg / mL; And / or, the precursor solution contains 1.5% to 2.5% sodium alginate by mass.

5. The preparation method according to claim 1, characterized in that, The precursor solution in step S2 further includes acrylamide monomer, crosslinking agent and photoinitiator; Preferably, the precursor solution further includes a zwitterionic monomer; Preferably, the acrylamide monomer includes at least one selected from N-hydroxyethylacrylamide, N,N-dimethylacrylamide, acrylamide, and N-isopropylacrylamide; Preferably, the zwitterionic monomer comprises betaine sulfonate methacrylate; Preferably, the crosslinking agent includes at least one selected from N,N-methylbisacrylamide, polyethylene glycol diacrylate, hexamethylenebisacrylamide, ethylene glycol diacrylate, and dipropylene glycol diacrylate. Preferably, the photoinitiator comprises at least one selected from 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone, 1-hydroxy-cyclohexyl-phenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and 2,2'-azobisisobutylamidine dihydrochloride.

6. The preparation method according to claim 5, characterized in that, The concentration of acrylamide monomer in the precursor solution is 21.3–213 mg / mL; Preferably, the concentration of the crosslinking agent in the precursor solution is 0.463–0.935 mg / mL; Preferably, the concentration of the photoinitiator in the precursor solution is 13.46–26.92 mg / mL.

7. The preparation method according to claim 5, characterized in that, Step S2 further includes: removing excess solution after the reaction and irradiating with an ultraviolet lamp; Preferably, the reaction time is 3 to 10 minutes; Preferably, the irradiation time of the ultraviolet lamp is 2 to 5 hours; Preferably, the wavelength of the ultraviolet lamp irradiation is 340–400 nm; Preferably, the power of the ultraviolet lamp is 15-20W.

8. The hydrogel coating prepared by the preparation method according to any one of claims 1 to 7.

9. A coated product, characterized in that, The coated product includes a substrate and a hydrogel coating coated on the surface of the substrate, wherein the hydrogel coating is prepared by the preparation method described in any one of claims 1 to 7.

10. The use of the preparation method according to any one of claims 1 to 7 in the preparation of antifouling and / or lubricating products.

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