An ultra-lubricating oil and water repellent hydrogel with wrinkles and a preparation method and application thereof

Abstract

The application discloses an oil-repellent super-lubricating hydrogel with wrinkles and a preparation method and application thereof, and relates to the technical field of marine ship body oil-repellent technology.The method comprises the following steps: adding a hydrophobic polymer monomer into an organic solvent, uniformly mixing, and preparing a mixed solution; adding a synthetic emulsion containing a hydrophilic polymer, uniformly mixing, then adding a crosslinking agent and an initiator, uniformly stirring, and preparing a precursor solution; performing ultraviolet light irradiation polymerization, preparing a cured hydrogel, then performing solvent exchange, and preparing the oil-repellent super-lubricating hydrogel with wrinkles.The hydrogel is constructed by a surface entanglement double-layer structure, and a surface wrinkle morphology is introduced, so that the obtained hydrogel has excellent mechanical strength, a low friction coefficient and excellent oil-repellent performance.The application solves the problems of insufficient lubricity and poor stability in a complex marine environment of the existing hydrogel antifouling materials.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of marine hull oil-proof technology, in particular to a super-lubricating oil-proof hydrogel with wrinkles and a preparation method and application thereof. BACKGROUND

[0002] With the rapid development of shipbuilding industry and marine engineering, the hull is easily contaminated by oil pollution, microorganisms and suspended particles in the marine environment during long-term service, resulting in increased adhesion resistance, reduced speed, rising fuel consumption and increased maintenance costs, which seriously affects the service life and operating efficiency of the ship. Especially in complex marine conditions, the coating material not only needs to have good antifouling performance, but also needs to meet the comprehensive performance of high wear resistance, low friction coefficient and good service stability. Traditional antifouling coatings mostly use low surface energy materials or metal additives to reduce the adhesion of pollutants, but the coating structure is usually flat, lacks fine control of surface energy and lubrication state, and the material is prone to peeling, aging, cracking and other problems during long-term service, resulting in a decrease in antifouling ability. In addition, such materials exhibit poor oil resistance in oil-contaminated environments, making it difficult to meet the dual requirements of self-cleaning and low adhesion for marine equipment. Therefore, the development of green and environmentally friendly antifouling materials with lubricity, oil resistance and mechanical stability has become a research hotspot.

[0003] Hydrogel materials have been widely concerned in the field of marine antifouling due to their excellent hydrophilicity and lubricity. They can form a stable hydration layer in water, effectively reducing the interfacial friction and inhibiting the adhesion of pollutants. However, conventional hydrogels have problems such as insufficient lubricity, instability, and short lubrication duration in extreme environments, which limits their application in more complex service environments. Therefore, how to construct a hydrogel material with excellent mechanical properties, strong lubricity and long-term stable service in marine environment has become a key problem to be solved in the field of marine antifouling materials. SUMMARY

[0004] To solve the above technical problems, the purpose of the present application is to provide a super-lubricating oil-proof hydrogel with wrinkles and a preparation method and application thereof, to solve the problems of insufficient lubricity and poor stability of existing hydrogel antifouling materials in complex marine environments.

[0005] The technical solution of the present application to solve the above technical problems is as follows: a preparation method of a super-lubricating oil-proof hydrogel with wrinkles is provided, comprising the following steps:

[0006] (1) adding a hydrophobic polymer monomer into an organic solvent and mixing uniformly to obtain a mixed solution;

[0007] (2) adding a synthetic emulsion containing a hydrophilic polymer into the mixed solution prepared in step (1), mixing uniformly, and then adding a crosslinking agent and an initiator, and stirring uniformly to prepare a precursor solution;

[0008] (3) polymerizing the precursor solution prepared in step (2) by ultraviolet irradiation to prepare a cured hydrogel, and then performing solvent exchange to prepare a super-lubricating oil-repellent hydrogel with wrinkles.

[0009] Based on the technical scheme, the application further has the following improvements:

[0010] Further, in step (1), the hydrophobic polymer monomer is methyl acrylate, ethylene, lactic acid, caprolactam, acrylonitrile, terephthalate glycol or carbonate.

[0011] Further, in step (1), the hydrophobic polymer monomer is methyl acrylate.

[0012] Further, in step (1), the organic solvent is dimethyl sulfoxide or N,N-dimethylformamide.

[0013] Further, in step (1), the organic solvent is dimethyl sulfoxide.

[0014] Further, in step (1), the volume ratio of the hydrophobic polymer monomer to the mixed solution is 2-6 mL: 10 mL.

[0015] Further, in step (1), the volume ratio of the hydrophobic polymer monomer to the mixed solution is 2 mL: 10 mL.

[0016] Further, in step (1), the magnetic stirring is performed at 20-60 ℃ for 30-60 min, and the mixture is uniformly mixed.

[0017] Further, in step (1), the magnetic stirring is performed at 25 ℃ for 40 min, and the mixture is uniformly mixed.

[0018] Further, the rotating speed of the magnetic stirring is 100-2000 r / min.

[0019] Further, the rotating speed of the magnetic stirring is 1000 r / min.

[0020] Further, in step (2), the hydrophilic polymer in the synthetic emulsion containing a hydrophilic polymer is a mixture of 2-acrylamide-2-methylpropane sulfonic acid and any two of the following four substances: polyacrylic acid, polyvinyl alcohol, polyphthalamide and polyacrylamide.

[0021] Further, in step (2), the synthetic emulsion containing a hydrophilic polymer is water-in-oil type.

[0022] Further, in step (2), the synthetic emulsion containing the hydrophilic polymer is a water-in-oil emulsion containing the hydrophilic polymer.

[0023] Further, in step (2), the synthetic emulsion containing the hydrophilic polymer is prepared by the following method: S1: reacting CBA and OA to prepare a surfactant;

[0024] S2: sequentially adding the hydrophilic polymer monomer and the surfactant prepared in step S1 into deionized water, stirring, adjusting the pH value, adding white oil, and mixing uniformly to prepare a monomer emulsion;

[0025] S3: performing a reverse emulsion polymerization reaction on the monomer emulsion prepared in step S2 to prepare the synthetic emulsion containing the hydrophilic polymer.

[0026] Further, in step (2), the crosslinking agent is at least one of 2-acrylamido-2-methylpropanesulfonic acid sodium salt, divinyl acid ester, ethylene glycol dimethacrylate, trimethylpropane trimethacrylate, methylene bisacrylamide, and N,N-methylene bisacrylamide.

[0027] Further, in step (2), the crosslinking agent is N,N-methylene bisacrylamide.

[0028] Further, in step (2), the initiator is 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone or lithium phenyl-2,4,6-trimethylbenzoylphosphinate.

[0029] Further, in step (2), the initiator is 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone.

[0030] Further, in step (2), the volume-to-mass ratio of the mixed solution, the synthetic emulsion containing the hydrophilic polymer, the crosslinking agent, and the initiator is 10 mL: 0.1-0.5 g: 2-5 mg: 5-10 mg.

[0031] Further, in step (2), the volume-to-mass ratio of the mixed solution, the synthetic emulsion containing the hydrophilic polymer, the crosslinking agent, and the initiator is 10 mL: 0.4 g: 5 mg: 10 mg.

[0032] Further, in step (2), the mixed solution is uniformly mixed by magnetic stirring at 20-60°C for 30-180 min.

[0033] Further, in step (2), the mixed solution is uniformly mixed by magnetic stirring at 25°C for 120 min.

[0034] Further, in step (3), the polymerization is performed for 2-6 h.

[0035] Further, in step (3), the solidified hydrogel is soaked in deionized water for solvent exchange.

[0036] Further, the deionized water is replaced at 1h, 3h, 6h, 11h, 23h, 47h, 71h, 95h, 119h, 143h, 167h.

[0037] Further, the deionized water is replaced at 1h, 3h, 6h, 11h, 23h.

[0038] Further, the deionized water is replaced at 1h, 3h, 6h, 11h, 23h, 47h.

[0039] Further, in step (3), the thickness of the super-lubricating oil-repellent hydrogel with wrinkles is 0.5-3mm.

[0040] The application also provides the super-lubricating oil-repellent hydrogel with wrinkles prepared by the above method.

[0041] The application also provides the application of the super-lubricating oil-repellent hydrogel with wrinkles in ship body oil-proofing.

[0042] The application has the following beneficial effects:

[0043] 1、The hydrogel of the application has excellent mechanical strength, low friction coefficient and excellent oil-repellent performance by constructing a surface entanglement double-layer structure and introducing a surface wrinkle morphology, and is suitable for long-term antifouling, oil-proofing and drag reduction of ship body surface. The material has the advantages of stable structure and wide environmental adaptability, and can effectively improve the service life and service performance of ship body coating.

[0044] 2、The method of the application can control the polymerization and crosslinking time by selecting appropriate initiators and suitable synthetic emulsion content and polymerization temperature, so that the prepared hydrogel has good performance, and the production cost can be controlled by selecting hydrophobic polymers with low cost and wide source.

[0045] 3、The raw materials for preparing the hydrogel include a synthetic emulsion, a hydrophobic polymer monomer, an initiator, a crosslinking agent, an organic solvent and water. Since the density of the synthetic emulsion is less than the density of the solvent, the synthetic emulsion after solvent exchange will be demulsified on the surface of the hydrophobic polymer network to release the hydrophilic polymer chains in the water phase. In this process, the hydrophilic polymer chains are interpenetrated and entangled on the surface of the hydrophobic polymer network. Since the hydrophilic groups (amide groups, carboxyl groups, hydroxyl groups, etc.) in the hydrophilic polymer chains interact with water molecules, a super strong hydration layer is formed, so that the upper surface of the hydrogel has super hydrophilic performance, and a super low lubrication coefficient is obtained. At the same time, the mechanical properties of the hydrogel are enhanced due to the entanglement. And due to the swelling difference between the hydrophilic chains and the hydrophobic polymer network, wrinkles are formed on the upper surface of the obtained hydrogel. Therefore, the synergistic effect of hydrophilicity and wrinkles makes the hydrogel have a super low friction coefficient and super strong lubricating performance, which is suitable for ship body oil-proofing. The super-lubricating surface can completely block the adhesion of oil stains.

[0046] 4、Compared with the traditional method, such as grafting polymer to form a hydration layer or introducing lipids to release lubricants by etching, the grafted layer is easy to fall off in repeated shearing, and the lipid system is complex to prepare and has poor repeatability. The hydrophobic polymer is used as the skeleton to form a flexible and stable gel network. After demulsification, the hydrophilic polymer chains are released and form an entangled layer on the surface, which constitutes the basis of the lubricating structure, and a high-performance lubricating interface is constructed through the phase separation behavior in the demulsification process. The one-step entangled layer strategy proposed in the application has significant advantages in structural stability and preparation process. Not only does it avoid multi-step processing, but it also maintains the stability of the lubricating layer in dynamic shearing, realizes low friction coefficient, and improves reliability and service life. The application solves the problem of lubrication failure caused by the falling of grafted brushes due to repeated shearing or harsh environment (high load). BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 The upper surface of the hydrogel prepared for Example 6 and Comparative Example 1 is compared;

[0048] Figure 2 The tensile stress curve of the hydrogel prepared for Example 6 and Comparative Example 1 is shown in the figure;

[0049] Figure 3 The friction coefficient (COF) of the hydrogel prepared for Example 6 and Comparative Example 1 is shown in the figure;

[0050] Figure 4 The hydrogel prepared for Example 6 is shown in the figure. DETAILED DESCRIPTION

[0051] The principles and features of the present application are described below in conjunction with the accompanying drawings, which are presented only for the purpose of illustrating the present application and are not intended to limit the scope of the present application. The specific conditions not specified in the examples are carried out according to the conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments used are not specified by the manufacturer, but are conventional products that can be purchased on the market.

[0052] The synthetic emulsion containing the hydrophilic polymer in the following examples is prepared by the following method:

[0053] S1: CBA (4-carboxybenzaldehyde) is added to ethanol (solvent), stirred to completely dissolve, and then OA (oleylamine) is added in a 1:1 molar ratio in equal proportions, magnetically stirred at room temperature for 4 h, and the solvent in the product is evaporated after sufficient reaction to obtain a dynamic covalent surfactant OA-CBA;

[0054] S2: AMPS, hydrophilic polymer monomer 1, and hydrophilic polymer monomer 2 (polyacrylic acid and polyvinyl alcohol in examples 1-6) are added in a 9:5:3 molar ratio in deionized water solution, dissolved by magnetic stirring, then OA-CBA is added, the pH value of the aqueous solution is adjusted, and then mixed with 5# white oil to form a monomer emulsion at room temperature.

[0055] S3: Reverse emulsion polymerization of the monomer emulsion: the stable monomer emulsion is maintained at room temperature, nitrogen is continuously introduced into the emulsion system, and mechanical stirring is maintained to maintain system stability. Subsequently, 0.01% of an oxidizing agent and a reducing agent based on the total weight of the monomers are added to the emulsion to initiate polymerization. The system is continuously heated to 40°C. The polymerization reaction is carried out under the conditions of nitrogen blowing and stirring, and finally the required water-in-oil emulsion is obtained.

[0056] Example 1:

[0057] A super-lubricating oil-repellent water-repellent hydrogel with wrinkles, the preparation method comprising the following steps:

[0058] (1) Hydrophobic polymer monomer (2 mL of methyl acrylate (MA)) is added to an organic solvent (8 mL of dimethyl sulfoxide (DMSO)), magnetically stirred at 25°C for 40 min, the stirring speed is 1000 r / min, and a mixed solution is prepared;

[0059] (2) adding a synthetic emulsion containing hydrophilic polymer (0.1 g of 2-acrylamide-2-methylpropane sulfonic acid, polyacrylic acid and polyvinyl alcohol) into the mixed solution prepared in step (1), magnetically stirring at 40°C for 60 min at a stirring speed of 1000 r / min, mixing uniformly, then adding a crosslinking agent (2 mg of N,N-methylene bisacrylamide) and an initiator (5 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (I2959)), stirring uniformly, to prepare a precursor solution;

[0060] (3) pouring the precursor solution prepared in step (2) into a square mold, placing under an ultraviolet lamp, performing ultraviolet irradiation polymerization for 2 h, to prepare a cured hydrogel, then performing solvent exchange, replacing deionized water at 1 h, 3 h, 6 h, 11 h, 23 h, to prepare an ultra-lubricating oil-repellent hydrogel with wrinkles.

[0061] Example 2:

[0062] An ultra-lubricating oil-repellent hydrogel with wrinkles, a preparation method thereof comprising the following steps:

[0063] (1) adding a hydrophobic polymer monomer (3 mL of ethylene) into an organic solvent (7 mL of dimethyl sulfoxide (DMSO)), magnetically stirring at 30°C for 35 min at a stirring speed of 1000 r / min, mixing uniformly, to prepare a mixed solution;

[0064] (2) adding a synthetic emulsion containing hydrophilic polymer (0.5 g of 2-acrylamide-2-methylpropane sulfonic acid, polyacrylic acid and polyvinyl alcohol) into the mixed solution prepared in step (1), magnetically stirring at 35°C for 35 min at a stirring speed of 1000 r / min, mixing uniformly, then adding a crosslinking agent (3 mg of 2-acrylamide-2-methylpropane sulfonic acid sodium salt) and an initiator (6 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone), stirring uniformly, to prepare a precursor solution;

[0065] (3) pouring the precursor solution prepared in step (2) into a square mold, placing under an ultraviolet lamp, performing ultraviolet irradiation polymerization for 2 h, to prepare a cured hydrogel, then performing solvent exchange, replacing deionized water at 1 h, 3 h, 6 h, 11 h, 23 h, 47 h, 71 h, to prepare an ultra-lubricating oil-repellent hydrogel with wrinkles.

[0066] Example 3:

[0067] An ultra-lubricating oil-repellent hydrogel with wrinkles, a preparation method thereof comprising the following steps:

[0068] (1) hydrophobic polymer monomer (4 mL lactic acid (LA)) was added to an organic solvent (6 mL N,N-dimethylformamide (DMF)), and stirred at 25°C for 40 min at a magnetic stirring speed of 1000 r / min, and mixed uniformly to obtain a mixed solution;

[0069] (2) the mixed solution obtained in step (1) was added with a synthetic emulsion containing hydrophilic polymers (0.2 g 2-acrylamide-2-methyl propane sulfonic acid, polyacrylic acid and polyvinyl alcohol), and stirred at 45°C for 50 min at a magnetic stirring speed of 1000 r / min, and mixed uniformly, and then a crosslinking agent (4 mg divinyl acid ester) and an initiator (6 mg lithium phenyl-2,4,6-trimethyl benzoyl phosphonic acid salt) were added and stirred uniformly to obtain a precursor solution;

[0070] (3) the precursor solution obtained in step (2) was poured into a square mold, and subjected to ultraviolet light irradiation polymerization under a UV lamp for 2 h to obtain a cured hydrogel, and then solvent exchange was performed, and deionized water was replaced at 1 h, 3 h, 6 h, 11 h, 23 h and 47 h to obtain an ultra-lubricating oil-repellent hydrogel with wrinkles.

[0071] Example 4:

[0072] An ultra-lubricating oil-repellent hydrogel with wrinkles was prepared by the following steps:

[0073] (1) hydrophobic polymer monomer (3 mL caprolactam) was added to an organic solvent (7 mL dimethyl sulfoxide (DMSO)), and stirred at 40°C for 40 min at a magnetic stirring speed of 1000 r / min, and mixed uniformly to obtain a mixed solution;

[0074] (2) the mixed solution obtained in step (1) was added with a synthetic emulsion containing hydrophilic polymers (0.4 g 2-acrylamide-2-methyl propane sulfonic acid, polyacrylic acid and polyvinyl alcohol), and stirred at 50°C for 90 min at a magnetic stirring speed of 1000 r / min, and mixed uniformly, and then a crosslinking agent (5 mg ethylene glycol dimethyl acrylate) and an initiator (8 mg 2-hydroxy-4'-(2-hydroxyethoxy)-2-methyl propiophenone) were added and stirred uniformly to obtain a precursor solution;

[0075] (3) the precursor solution obtained in step (2) was poured into a square mold, and subjected to ultraviolet light irradiation polymerization under a UV lamp for 5 h to obtain a cured hydrogel, and then solvent exchange was performed, and deionized water was replaced at 1 h, 3 h, 6 h, 11 h, 23 h, 47 h, 71 h and 95 h to obtain an ultra-lubricating oil-repellent hydrogel with wrinkles.

[0076] Example 5:

[0077] A super-lubricity oil-proof hydrogel with wrinkles, the preparation method comprising the following steps:

[0078] (1) hydrophobic polymer monomer (5 mL of acrylonitrile (AN)) is added to an organic solvent (5 mL of N,N-dimethylformamide (DMF)), and magnetic stirring is carried out at 25°C for 40 min, the stirring speed is 1000 r / min, and mixing is uniform, so as to prepare a mixed solution;

[0079] (2) the mixed solution prepared in step (1) is added with a synthetic emulsion containing hydrophilic polymers (0.3 g of 2-acrylamide-2-methylpropane sulfonic acid, polyacrylic acid and polyvinyl alcohol), and magnetic stirring is carried out at 35°C for 120 min, the stirring speed is 1000 r / min, and mixing is uniform, then a crosslinking agent (3 mg of trimethylpropane trimethyl acrylate) and an initiator (7 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methyl benzopropenone) are added and stirred uniformly, so as to prepare a precursor solution;

[0080] (3) the precursor solution prepared in step (2) is poured into a square mold, and ultraviolet light irradiation polymerization is carried out under a UV lamp for 3 h, so as to prepare a cured hydrogel, then solvent exchange is carried out, and deionized water is replaced at 1 h, 3 h, 6 h, 11 h, 23 h, 47 h, 71 h, 95 h and 119 h, so as to prepare a super-lubricity oil-proof hydrogel with wrinkles.

[0081] Example 6:

[0082] A super-lubricity oil-proof hydrogel with wrinkles, the preparation method comprising the following steps:

[0083] (1) hydrophobic polymer monomer (2 mL of methyl acrylate (MA)) is added to an organic solvent (8 mL of dimethyl sulfoxide (DMSO)), and magnetic stirring is carried out at 25°C for 40 min, the stirring speed is 1000 r / min, and mixing is uniform, so as to prepare a mixed solution;

[0084] (2) the mixed solution prepared in step (1) is added with a synthetic emulsion containing hydrophilic polymers (0.4 g of 2-acrylamide-2-methylpropane sulfonic acid, polyacrylic acid and polyvinyl alcohol), and magnetic stirring is carried out at 25°C for 120 min, the stirring speed is 1000 r / min, and mixing is uniform, then a crosslinking agent (5 mg of N,N-methylene bisacrylamide) and an initiator (10 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methyl benzopropenone) are added and stirred uniformly, so as to prepare a precursor solution;

[0085] (3) The precursor solution prepared in step (2) is poured into a square mold, and placed under a UV lamp for UV irradiation polymerization for 3 h to prepare a cured hydrogel, and then solvent exchange is performed, and deionized water is replaced at 1 h, 3 h, 6 h, 11 h, 23 h, 47 h, 71 h, 95 h, 119 h, 143 h, and 167 h to prepare a super-lubricating and oil-repellent hydrogel with wrinkles.

[0086] Example 7

[0087] A super-lubricating and oil-repellent hydrogel with wrinkles is prepared by the following steps:

[0088] (1) Hydrophobic polymer monomers (2 mL of ethylene glycol terephthalate) are added to an organic solvent (8 mL of N,N-dimethylformamide (DMSO)), and magnetically stirred at 25°C for 40 min at a stirring speed of 1000 r / min, and mixed uniformly to prepare a mixed solution;

[0089] (2) The mixed solution prepared in step (1) is added with a synthetic emulsion containing hydrophilic polymers (0.1 g of 2-acrylamide-2-methylpropane sulfonic acid, polyacrylic acid, and polyacrylamide), and magnetically stirred at 40°C for 60 min at a stirring speed of 1000 r / min, and mixed uniformly, and then added with a crosslinking agent (2 mg of methylene bisacrylamide) and an initiator (5 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylbenzophenone), and stirred uniformly to prepare a precursor solution;

[0090] (3) The precursor solution prepared in step (2) is poured into a square mold, and placed under a UV lamp for UV irradiation polymerization for 2 h to prepare a cured hydrogel, and then solvent exchange is performed, and deionized water is replaced at 1 h, 3 h, 6 h, 11 h, and 23 h to prepare a super-lubricating and oil-repellent hydrogel with wrinkles.

[0091] Example 8

[0092] A super-lubricating and oil-repellent hydrogel with wrinkles is prepared by the following steps:

[0093] (1) Hydrophobic polymer monomers (2 mL of ethylene glycol terephthalate) are added to an organic solvent (8 mL of N,N-dimethylformamide (DMSO)), and magnetically stirred at 25°C for 40 min at a stirring speed of 1000 r / min, and mixed uniformly to prepare a mixed solution;

[0094] (2) adding a synthetic emulsion containing a hydrophilic polymer (0.1 g of 2-acrylamide-2-methylpropane sulfonic acid, polyvinyl alcohol, and polyphthalamide) to the mixed solution prepared in step (1), magnetically stirring at 20°C for 180 min at a stirring speed of 100 r / min, uniformly mixing, then adding a crosslinking agent (2 mg of divinyl adipate) and an initiator (5 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (I2959)), uniformly stirring, and preparing a precursor solution;

[0095] (3) pouring the precursor solution prepared in step (2) into a square mold, performing ultraviolet irradiation polymerization under a UV lamp for 2 h, preparing a cured hydrogel, then performing solvent exchange, replacing deionized water at 1 h, 3 h, 6 h, 11 h, and 23 h, and preparing an ultra-lubricating oil-repellent hydrogel with wrinkles.

[0096] Example 9:

[0097] An ultra-lubricating oil-repellent hydrogel with wrinkles, the preparation method comprising the following steps:

[0098] (1) adding a hydrophobic polymer monomer (2 mL of polylactic acid (PLA)) to an organic solvent (8 mL of N,N-dimethylformamide (DMF)), magnetically stirring at 60°C for 30 min at a stirring speed of 2000 r / min, uniformly mixing, and preparing a mixed solution;

[0099] (2) adding a synthetic emulsion containing a hydrophilic polymer (0.1 g of 2-acrylamide-2-methylpropane sulfonic acid, polyphthalamide, and polyacrylamide) to the mixed solution prepared in step (1), magnetically stirring at 60°C for 30 min at a stirring speed of 2000 r / min, uniformly mixing, then adding a crosslinking agent (2 mg of ethylene glycol dimethacrylate) and an initiator (5 mg of lithium phenyl-2,4,6-trimethylbenzoyl phosphonate), uniformly stirring, and preparing a precursor solution;

[0100] (3) pouring the precursor solution prepared in step (2) into a square mold, performing ultraviolet irradiation polymerization under a UV lamp for 2 h, preparing a cured hydrogel, then performing solvent exchange, replacing deionized water at 1 h, 3 h, 6 h, 11 h, and 23 h, and preparing an ultra-lubricating oil-repellent hydrogel with wrinkles.

[0101] Comparative Example 1:

[0102] A hydrogel, the preparation method comprising the following steps:

[0103] In step (2), no synthetic emulsion containing a hydrophilic polymer is added, and the rest is the same as in Example 6.

[0104] Test Example

[0105] Figures 1-3 In particular, 0% synthetic emulsion is Comparative Example 1, and 4% synthetic emulsion is Example 6.

[0106] I. Morphology

[0107] The upper surface of the hydrogel prepared by Example 6 and Comparative Example 1 was compared, and the results are shown in Figure 1 .

[0108] As can be seen from Figure 1 , the surface of the hydrogel with 4% synthetic emulsion content has changed significantly compared to the hydrogel with 0% synthetic emulsion content. This is because the entanglement degree of the top layer and the main body of the hydrogel is different during the preparation of the hydrogel, which makes the surface form ordered wrinkles, which is beneficial to the storage of water in the hydrogel and can effectively reduce the contact area when rubbing to obtain a lower friction coefficient.

[0109] II. Tensile stress and elongation at break

[0110] The hydrogels prepared by Example 6 and Comparative Example 1 were tested for tensile properties in accordance with the national standard “GB / T 528-2009”. The tensile stress is the reaction force per unit area of an object to an external force that tends to stretch the object. The greater the tensile stress, the higher the strength of the sample. The elongation at break is the percentage of the increase in length of the effective marking portion when the flat wire is stretched to the point of rupture to the initial length of the effective marking portion. The greater the elongation at break, the higher the flexibility and elasticity of the sample.

[0111] The specific test method is as follows: the hydrogel is made into a cuboid sample with a thickness of 4.0±0.2 mm, a length of 50±0.5 mm, and a width of 10±0.5 mm. The sample is stretched at room temperature, and the spring scale reading and the sample length when the sample is broken are recorded. The tensile stress and the elongation at break are calculated by the following formula:

[0112] Tensile stress: σ = P / (b×d);

[0113] Wherein: σ is the tensile strength or tensile strength, unit Pa; P is the spring scale reading, unit N; b is the sample width, unit mm; d is the sample thickness, unit mm;

[0114] Elongation at break: ε = [(L-L0) / L0]×100%;

[0115] Wherein: ε is the elongation at break, unit %; L is the length of the sample when it is broken, unit mm; L0 is the initial length of the sample, unit mm;

[0116] The results are shown in Figure 2 .

[0117] As can be seen from Figure 2 The hydrogel prepared in Example 6 has good flexibility and toughness, and the tensile strength can reach 137.5 kpa.

[0118] III. Coefficient of friction

[0119] The hydrogel prepared in Example 6 and Comparative Example 1 was subjected to coefficient of friction detection. The coefficient of friction of the hydrogel under different conditions was obtained by a multifunctional friction and wear ball-on-disc reciprocating friction and wear tester. The test was carried out under the conditions of a sliding speed of 0.1 mm / s and a normal load of 0.5 N, the counter-attacking material was a stainless steel ball with a diameter of 10 mm, deionized water was used as a lubricant, and each test involved a reciprocating linear motion with a stroke length of 10 mm. The results are shown in Figure 3 .

[0120] As can be seen from Figure 3 The hydrogel prepared in Example 6 has an ultra-low coefficient of friction on the upper surface after adding the synthetic emulsion, and the upper surface of the hydrogel has ultra-high lubricating performance. It can form a stable super-strong hydration layer in a water environment, prevent the adhesion of oil stains, and thus is suitable for oil-proofing in marine environments.

[0121] IV. Oil-proofing function

[0122] The hydrogel prepared in Example 6 was subjected to oil-proofing function detection. The specific detection method was as follows: the hydrogel (MEDH4) was adhered to the surface of wood, a layer of oil phase was coated on the surface of the wood and the hydrogel, the material was placed in deionized water, and after slight shaking, it was found that the oil phase on the surface of the gel body was completely ineffective, while the oil phase on the surface of the wood itself remained. The results are shown in Figure 4 . Figure 4 , where the left image is the state without shaking, and the right image is the state after slight shaking.

[0123] As can be seen from Figure 4 The oil phase on the surface of the hydrogel after washing in water was completely removed, while the oil phase on the surface of the wood remained, which was due to the strong hydration layer on the surface of the hydrogel providing ultra-low friction, so that the adhesion ability of the oil phase to it was extremely weak.

[0124] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing a super-lubricating oil and water repellent hydrogel with wrinkles, characterized in that, The method comprises the following steps: (1) adding hydrophobic polymer monomers into an organic solvent and mixing uniformly to obtain a mixed solution; (2) adding a synthetic emulsion containing hydrophilic polymers into the mixed solution obtained in step (1) and mixing uniformly, then adding a crosslinking agent and an initiator and stirring uniformly to obtain a precursor solution; (3) performing ultraviolet irradiation polymerization on the precursor solution obtained in step (2) to obtain a cured hydrogel, and then performing solvent exchange to obtain a super-lubricating oil-repellent hydrogel with wrinkles; In step (2), the synthetic emulsion containing hydrophilic polymers is a water-in-oil emulsion containing hydrophilic polymers. In step (3), the solvent exchange is performed by immersing the cured hydrogel in deionized water.

2. The method for preparing super-lubricating oil and water repellent hydrogel with wrinkle according to claim 1, characterized in that, In step (1), the hydrophobic polymer monomers are methyl acrylate.

3. The method of preparing super-lubricating oil and water repellent hydrogel with wrinkles according to claim 1, characterized in that, In step (1), the organic solvent is dimethyl sulfoxide or N,N-dimethylformamide.

4. The method of preparing super-lubricating oil and water repellent hydrogel with wrinkles according to claim 1, characterized in that, In step (2), the crosslinking agent is at least one of divinyl ester, dimethyl glycol acrylate, trimethylolpropane triacrylate and N,N-methylene bisacrylamide.

5. The method of preparing super-lubricating oil and water repellent hydrogel with wrinkles according to claim 1, characterized in that, In step (2), the initiator is 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone or lithium phenyl-2,4,6-trimethylbenzoyl phosphinate.

6. The method of preparing super-lubricating oil and water repellent hydrogel with wrinkles according to claim 1, wherein, In step (3), the polymerization is performed for 2-6 h.

7. The method of preparing super-lubricating oil and water repellent hydrogel with wrinkles according to claim 1, wherein, In step (3), the super-lubricating oil-repellent hydrogel with wrinkles has a thickness of 0.5-3 mm.

8. A super-lubricating, oil and water repellent hydrogel having a pleat, characterized by, The hydrogel is prepared by the method for preparing the super-lubricating oil-repellent hydrogel with wrinkles according to any one of claims 1-7.

9. Use of the super-lubricating oil-repellent hydrogel with wrinkles according to claim 8 in ship hull oil-proofing.

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