An antibacterial and anti-icing coating

Abstract

This invention relates to the field of anti-icing technology. It provides a coating that combines antibacterial properties and low ice adhesion, solving the problem of antifreeze oil failing to secrete into ice in dry air, while simultaneously allowing for the continuous secretion of antibacterial substances onto the coating surface. This antibacterial, low-ice-adhesion, anti-icing coating comprises a surface layer formed by a hydrogel component and an antibacterial lubricant. The hydrogel component includes an interpenetrating double-network hydrogel formed by a zwitterionic polymer and chitosan, with chitosan forming a physically cross-linked sacrificial network. The antibacterial lubricant includes antimicrobial peptides. The hydrophilic sites of the interpenetrating double-network hydrogel formed by the zwitterionic polymer and chitosan can bind water molecules on the coating surface, forming a water-lubricating layer. The formation of this water-lubricating layer allows lubricating substances and free antimicrobial peptides from the antibacterial lubricant in the coating to be continuously released into the water-lubricating layer under osmotic pressure, achieving a continuous and stable antibacterial lubrication effect.

Description

Technical Field

[0001] This invention relates to the field of anti-icing technology, specifically to an antibacterial and anti-icing coating. Background Technology

[0002] Icing and frost formation cause significant inconvenience to people's production and daily life, and can result in substantial economic losses. This is especially true for equipment that operates in cold environments, such as wind turbine blades, aircraft propellers, and ship hulls. Once ice adheres to the surface of operating equipment, it drastically increases the equipment's weight, shifts its center of gravity during operation, and alters the surrounding airflow, severely impacting its performance and potentially causing damage and serious consequences. Furthermore, equipment exposed to the external environment must withstand various weather conditions. It not only needs anti-icing properties in cold weather but also damping and buffering capabilities against heavy rain and hail. It must also contend with iron bacteria or sulfur-oxidizing bacteria in the air and rainwater adhering to the equipment surface, affecting its anti-adhesion properties and even corroding the surface. Marine biofouling, in particular, causes enormous economic and energy losses to the shipping industry.

[0003] To address the problem of icing or frosting on equipment, various surface heating structures and surface coating materials have been proposed in existing technologies. While surface heating structures can continuously heat and defrost, they are energy-intensive, costly, and involve complex construction processes. Surface coating materials, on the other hand, utilize their hydrophobic and lubricating properties to achieve anti-icing, de-icing, reduced ice adhesion strength, and anti-frost effects on equipment surfaces. Compared to surface heating structures, they offer advantages such as lower cost, lower energy consumption, and easier implementation. Existing technologies have investigated the ice adhesion effects of some surface coating materials, such as those incorporating lubricants or antifreeze oils. However, for completely frozen surfaces, the anti-adhesion effect of lubricants is limited, failing to melt accumulated ice crystals. Furthermore, the dry surface of the coating in a completely frozen state prevents the formation of a permeability differential, hindering the proper secretion of antifreeze oil.

[0004] In addition, the current anti-icing coatings generally use inorganic nano-silver, CuO / Cu2O, ZnO and other rough components and antibacterial agents to be directly added to the hydrophobic coating. Although they can increase the hydrophobicity of the coating and give it bactericidal and bacteriostatic functions, the inorganic components and organic components have poor mutual solubility, which can easily cause particle sedimentation, delamination and even cracking. Summary of the Invention

[0005] This invention provides an anti-icing coating that combines antibacterial properties and low ice adhesion, which solves the problem that the antifreeze oil in existing low ice adhesion anti-icing coatings cannot secrete into ice in dry air, while also continuously secreting antibacterial substances onto the coating surface.

[0006] The antibacterial and low-ice-adhesion anti-icing coating comprises a surface layer formed by a composite of a hydrogel component and an antibacterial lubricant. The hydrogel component comprises an interpenetrating double-network hydrogel formed by a composite of zwitterionic polymers and chitosan, with chitosan forming a physically cross-linked sacrificial network. The antibacterial lubricant includes antimicrobial peptides.

[0007] According to the technical solution of the present invention, firstly, the hydrogel component includes an interpenetrating double-network hydrogel formed by zwitterionic polymer and chitosan, which has good antibacterial properties. Furthermore, chitosan is a physical cross-linked network that can undergo sacrificial fracture and self-repair when subjected to impact or cutting, giving the coating better damping resistance and making it suitable for harsher environments such as rainstorms, strong winds, and hail.

[0008] Secondly, antimicrobial peptides are used as antimicrobial fillers. Antimicrobial peptides can be polyamino acid polypeptides containing basic amino acids, such as arginine, histidine, lysine, and ornithine. Antimicrobial peptides have good compatibility with hydrogels, can be uniformly dispersed in the coating, and can interact with microbial cell membranes through electrostatic forces, causing physical damage to bacterial morphology, creating pores, leading to the outflow of bacterial nutrients, and thus causing bacterial death. This has a highly efficient and broad-spectrum sterilization effect.

[0009] Finally, the hydrophilic sites of the interpenetrating double-network hydrogel formed by the zwitterionic polymer and chitosan can bind water molecules on the coating surface, forming confined water, lowering the freezing point, and still forming a water-lubricating layer at low temperatures. The formation of the water-lubricating layer allows the lubricating substances in the antibacterial lubricant in the coating and free antibacterial peptides to be continuously released into the water-lubricating layer under the action of osmotic pressure, achieving a continuous and stable antibacterial lubrication effect. This enables the coating surface to maintain a low ice adhesion strength in low-temperature environments and maintain good antibacterial performance in the equipment operating environment.

[0010] As a preferred technical solution, the zwitterionic polymer is prepared by free radical copolymerization of zwitterionic monomers and terminal carboxyl monomers.

[0011] According to the preferred technical solution, the zwitterionic polymer formed by zwitterionic and terminal carboxyl monomers has hydrophilic sites that can bind water molecules on the coating surface to form confined water, thereby lowering the freezing point of water on the coating surface. Thus, even if there is already an accumulated ice layer on the surface, the contact surface between the ice and the coating is melted by lowering the freezing point of water on the contact surface to form a water-lubricating layer. The water-lubricating layer can reduce the adhesion between the ice and the coating surface, thereby allowing the ice to be easily removed from the surface.

[0012] As a preferred technical solution, the zwitterionic monomer is one or more combinations of dodecyl ethoxysulfonate betaine, carboxylate betaine methacrylate, and 2-methacryloyloxyethyl phosphorylcholine, and the terminal carboxyl monomer is one or more combinations of methacrylic acid, acrylic acid, and undecenoic acid.

[0013] According to this preferred technical solution, a terminal carboxyl monomer with carbon-carbon double bonds is used, which can undergo free radical polymerization with zwitterionic monomers to generate zwitterionic hydrogel copolymers, making the coating structure more stable and having good hydrophilicity.

[0014] As a preferred technical solution, the zwitterionic monomer can be dodecyl ethoxysulfonate betaine, the terminal carboxyl monomer can be acrylic acid, and the free radical initiator can be azobisisobutyronitrile.

[0015] According to this preferred technical solution, dodecyl ethoxysulfonate betaine and acrylic acid undergo free radical polymerization to generate dodecyl ethoxysulfonate betaine acrylic acid copolymer. Acrylic acid also forms a small number of chemical bonds with chitosan, which makes the hydrogel network more stable. At the same time, the hydrophilic sites can bind water molecules to form confined water, which is more conducive to lowering the freezing point of water on the coating surface. It can also better store antibacterial lubricant, so that the antibacterial peptides and small molecule lubricating substances in the antibacterial lubricant can be released slowly and continuously.

[0016] As a preferred technical solution, the antibacterial lubricant also includes antifreeze oil, which is one or more combinations of glycerin, ethylene glycol, and derivatives of glycerin or ethylene glycol.

[0017] According to this preferred technical solution, antifreeze oil can significantly reduce the freezing point of water on the coating surface through synergistic action with the hydrogel component. A coating with only injected antifreeze oil needs to contact ice to lower the freezing point of water at the ice contact surface, melting some of the ice and thus reducing the adhesion between the ice and the coating surface, achieving de-icing. Furthermore, because the hydrophilic sites of the hydrogel component can bind to water molecules on the coating surface, forming confined water and lowering the freezing point, a water-lubricating layer is always maintained on the coating surface. Additionally, the antifreeze oil and antimicrobial peptides are continuously released into the water-lubricating layer. Therefore, a lubricating layer with anti-icing and antibacterial properties is always present on the coating surface, greatly improving the anti-icing performance of the coating surface.

[0018] As a preferred technical solution, the antimicrobial peptide includes: a fixed antimicrobial peptide and a free antimicrobial peptide, wherein the fixed antimicrobial peptide is coupled with chitosan; and the free antimicrobial peptide is dispersed in antifreeze oil.

[0019] According to this preferred technical solution, by adjusting the doping amount of antimicrobial peptides, the content of free antimicrobial peptides in the antifreeze oil can be adjusted. The free antimicrobial peptides in the antifreeze oil can continuously precipitate into the water lubrication layer on the coating surface along with the antifreeze oil. Meanwhile, the fixed antimicrobial peptides are coupled with the unreacted amino groups on the chitosan through the carboxyl groups on the antimicrobial peptides. This increases the antimicrobial properties of the hydrogel component, so that even after the free antimicrobial peptides are depleted, the coating can still maintain good antimicrobial properties.

[0020] As a preferred technical solution, the antibacterial and low-ice-adhesion anti-icing coating also includes modified nanoparticles, which are made by combining inorganic nanoparticles with biohydrophobic materials, including rosin or rosin derivatives.

[0021] According to the preferred technical solution, nanoparticles can make the coating surface have a certain size of nano-roughness, thereby forming a superhydrophobic surface. The nanoparticles modified with rosin or rosin derivatives can have both hydrophobicity and environmental friendliness, and can also improve the antibacterial properties of the coating.

[0022] As a preferred technical solution, zwitterionic polymers and chitosan are mixed to form a hydrogel precursor solution, and the hydrogel precursor solution is subjected to multiple freeze-thaw cycles to form a double-network hydrogel component.

[0023] According to the preferred technical solution, after the reactants are mixed, the zwitterionic monomers in the mixture are first polymerized and crosslinked, and then the mixture is subjected to multiple freeze-thaw cycles. During the freeze-thaw process, the chitosan in the mixture is physically crosslinked in a way that it is interspersed in the zwitterionic polymer crosslinking network, thereby realizing the construction of the chitosan sacrificial network.

[0024] As a preferred technical solution, antimicrobial peptides are dispersed in antifreeze oil to form an antimicrobial lubricant, and the surface layer is prepared by immersing the hydrogel component in the antimicrobial lubricant and allowing it to stand for at least 24 hours.

[0025] According to this preferred technical solution, the antibacterial lubricant penetrates into the coating through the gaps in the dual network structure of the hydrogel component, and after standing for more than 24 hours, it can better fill the gaps in the dual network structure of the hydrogel component, so that the antifreeze oil and antibacterial peptides in the antibacterial lubricant can be stably precipitated into the water lubrication layer on the surface of the coating for a long time. Attached Figure Description

[0026] Figure 1 This is a bar graph showing the plate test results of the sample coating-1 and the control sample prepared in the embodiments of the present invention;

[0027] Figure 2 This is a line graph showing the relationship between the ice sliding angle and temperature for sample coating-1 and sample coating-2 prepared in the embodiments of the present invention;

[0028] Figure 3 The tanδ-T of the sample coating-1 prepared in the embodiments of the present invention is... g A line graph showing the relationship between the two. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] This embodiment provides an antibacterial and low-ice-adhesion anti-icing coating, which includes a surface layer formed by a composite of a hydrogel component and an antibacterial lubricant.

[0031] [Hydrogel Components]

[0032] The hydrogel component includes at least an interpenetrating double-network hydrogel formed by a combination of zwitterionic polymers and chitosan.

[0033] Chitosan can be any commercially available chitosan, and a sacrificial network is formed through physical cross-linking. The method of physical cross-linking is not limited. Preferably, multiple freeze-thaw cycles can be used to allow chitosan to directly generate cross-linked hydrogen bonds. Since the temperature difference in the environment where the operating equipment is located is large, the hydrogen bonds generated by freeze-thaw can achieve self-recovery cross-linking with the temperature difference between day and night.

[0034] Zwitterionic polymers are prepared by free radical copolymerization of zwitterionic monomers and carboxyl-terminated monomers. For example, zwitterions may include one or more combinations of dodecylethoxysulfonate betaine, carboxylate betaine methacrylate, and 2-methacryloyloxyethylphosphorylcholine. Carboxyl-terminated monomers may include one or more combinations of methacrylic acid, acrylic acid, and undecenoic acid. Free radical initiators may include one or more combinations of azobisisobutyronitrile, azobisisoheptanenitrile, cumene hydroperoxide, tert-butyl hydroperoxide, and benzoyl. The zwitterionic polymers formed from zwitterions and carboxyl-terminated monomers have hydrophilic sites capable of binding water molecules, forming confined water, and lowering the freezing point of water on the coating surface. Therefore, even if an accumulated ice layer already exists on the surface, a water-lubricating layer is formed at the contact surface between the ice and the coating by lowering the freezing point of water at the contact surface.

[0035] Preferably, the zwitterionic monomer is dodecyl ethoxysulfonate betaine, the carboxyl-terminated monomer is acrylic acid, and the free radical initiator is azobisisobutyronitrile (AIBN). Dodecyl ethoxysulfonate betaine and acrylic acid undergo free radical polymerization in an ACBN to generate a dodecyl ethoxysulfonate betaine acrylic acid copolymer. Acrylic acid also forms a small number of chemical bonds with chitosan, which makes the hydrogel network more stable and allows for the binding of more confined water, thus lowering the freezing point of water on the coating surface. It also better stores the antibacterial lubricant, enabling the slow and continuous release of antimicrobial peptides and small molecule lubricants from the antibacterial lubricant.

[0036] [Antibacterial Lubricant]

[0037] Antimicrobial lubricants can be any substance containing antimicrobial peptides and having a lubricating effect. The antimicrobial peptides can be polyamino acid polypeptides containing basic amino acids, and the basic amino acids are one or more combinations of arginine, histidine, lysine and ornithine, which are not limited here.

[0038] Preferably, the antibacterial lubricant includes antifreeze oil and antimicrobial peptides. The antifreeze oil can be one or more combinations of glycerol, ethylene glycol, and derivatives of glycerol or ethylene glycol. In a preferred embodiment, glycerol is used as the antifreeze oil. Glycerol has a stabilizing effect on the structure of the antimicrobial peptides, which helps the antimicrobial peptides maintain high antibacterial activity. The antifreeze oil can significantly reduce the freezing point of water on the coating surface by working synergistically with the hydrogel components. A coating with simply injected antifreeze oil needs to come into contact with ice to lower the freezing point of water on the ice contact surface, melting part of the ice, thereby reducing the adhesion between the ice and the coating surface and achieving de-icing. Since the hydrophilic sites of the hydrogel components can bind water molecules in the air, lowering the freezing point of water, a water-lubricating layer is formed on the coating surface. This ensures that the coating surface always has a water-lubricating layer, and the antifreeze oil and antimicrobial peptides can be continuously released into the water-lubricating layer. Therefore, the coating surface always has a lubricating layer with anti-icing and antibacterial properties, greatly improving the anti-icing performance of the coating surface.

[0039] For example, antimicrobial peptides can include: fixed antimicrobial peptides and free antimicrobial peptides. The fixed antimicrobial peptides are coupled with chitosan. The free antimicrobial peptides are dispersed in antifreeze oil. By adjusting the doping amount of antimicrobial peptides, the content of free antimicrobial peptides in the antifreeze oil can be adjusted. For example, when cecropin is selected as the antimicrobial peptide, the molar ratio of antimicrobial peptides to chitosan is 1:1-3:1, and the molar ratio between antifreeze oil and antimicrobial peptides is 5:1-2:1. This ensures that both fixed and free antimicrobial peptides exist in the coating. The free antimicrobial peptides in the antifreeze oil can continuously precipitate into the water-lubricated layer on the surface of the coating along with the antifreeze oil. The fixed antimicrobial peptides are coupled with the unreacted amino groups on the chitosan through the carboxyl groups on the antimicrobial peptides. This increases the antimicrobial properties of the hydrogel component, so that the coating can still maintain good antimicrobial properties even after the free antimicrobial peptides are depleted.

[0040] It should be noted that this embodiment exemplifies the use of cephalosporin as an antimicrobial peptide, but the present invention is not limited thereto. Those skilled in the art will understand that other antimicrobial peptides may be selected to replace cephalosporin depending on the specific scenario or the required antimicrobial flora, which also falls within the scope of protection of the present invention.

[0041] Furthermore, the surface layer is prepared by immersing the hydrogel component in an antibacterial lubricant and allowing it to stand for at least 24 hours. The antibacterial lubricant penetrates into the coating through the gaps in the double network structure of the hydrogel component. After standing for more than 24 hours, it can better fill the gaps in the double network structure of the hydrogel component, so that the antifreeze oil and antibacterial peptides in the antibacterial lubricant can be stably precipitated into the water lubrication layer on the surface of the coating for a long time.

[0042] For example, the method for preparing the antibacterial and low-ice-adhesion anti-icing coating in this embodiment can be as follows:

[0043] A zwitterionic monomer (one or more combinations of dodecyl ethoxysulfonate betaine, carboxylate betaine methacrylate, and 2-methacryloyloxyethyl phosphorylcholine), a carboxyl-terminated monomer (one or more combinations of methacrylic acid, acrylic acid, and undecenoic acid), a free radical initiator, and chitosan were sequentially added to a solution and mixed thoroughly. The mixture was then irradiated with UV light to obtain a hydrogel precursor. The hydrogel precursor was frozen in a freezer and then thawed at room temperature with stirring. This freeze-thaw process was repeated at least twice until a double-network hydrogel was finally obtained.

[0044] Antifreeze oil and antimicrobial peptides are prepared in proportion and stirred evenly to obtain an antimicrobial lubricant. The hydrogel component is applied to the surface of the substrate and dried. The substrate is then completely immersed in the antimicrobial lubricant and left to stand for at least 24 hours to allow the lubricant to fully penetrate into the hydrogel component, resulting in an antimicrobial and low-ice-adhesion anti-icing coating.

[0045] Preferably, the antibacterial and low-ice-adhesion anti-icing coating may further include modified nanoparticles, which are made by combining inorganic nanoparticles with biohydrophobic materials, including rosin or rosin derivatives. The nanoparticles enable the coating surface to have a certain size of nanoscale roughness, thereby forming a superhydrophobic surface. Furthermore, the nanoparticles modified with rosin or rosin derivatives possess both hydrophobicity and environmental friendliness, and can also enhance the antibacterial properties of the coating.

[0046] In this embodiment, firstly, the hydrogel component comprises an interpenetrating double-network hydrogel formed by zwitterionic polymers and chitosan, exhibiting excellent antibacterial properties. Furthermore, the chitosan, being a physically cross-linked network, can undergo sacrificial fracture and self-repair upon impact or cutting, imparting better damping resistance to the coating and making it suitable for harsher environments such as heavy rain, strong winds, and hail. Secondly, antimicrobial peptides are used as antimicrobial fillers. These peptides can be polyamino acid polypeptides containing basic amino acids, specifically one or more combinations of arginine, histidine, lysine, and ornithine. The antimicrobial peptides exhibit good compatibility with the hydrogel, allowing for uniform dispersion within the coating. They can also interact with microbial cell membranes through electrostatic forces, causing physical damage to bacterial morphology, creating pores, and leading to the outflow of bacterial nutrients, ultimately resulting in bacterial death. This provides a highly efficient and broad-spectrum sterilization effect. Finally, the hydrophilicity of the interpenetrating double-network hydrogel formed by the zwitterionic polymer and chitosan can absorb small molecule water vapor and lock it in the coating surface, forming a water-lubricating layer. The formation of the water-lubricating layer allows the lubricating substances and free antimicrobial peptides in the antibacterial lubricant in the coating to be continuously released into the water-lubricating layer under the action of osmotic pressure, achieving a continuous and stable antibacterial lubrication effect. This enables the coating surface to maintain a low ice adhesion strength and good antibacterial performance in low-temperature environments.

[0047] The following specific material characterization experiments further demonstrate the performance of the antibacterial and low-ice-adhesion anti-icing coating provided in this embodiment.

[0048] 1. Material preparation

[0049] 1.1 Preparation of modified micro / nanoparticles

[0050] Hydroxylation of nano-silica particles: Nano-silica particles are treated with sulfuric acid solution, then washed and dried to form hydroxylated nano-silica particles.

[0051] Surface treatment of nano-silica particles: Rosin was dissolved in an ethanol solution, the pH was adjusted to be close to 8, hydroxylated nano-silica particles were added, stirred for 1 hour, washed, dried and ground to obtain modified micro- and nano-particles.

[0052] 1.2 Preparation of hydrogel components

[0053] Amphoteric monomers (dodecyl ethoxysulfonate betaine), carboxyl-terminated monomers (acrylic acid), free radical initiators (azobisisobutyronitrile), and quaternary ammonium chitosan were sequentially added to an ethanol-water solution. The reaction environment was a nitrogen atmosphere, the reaction temperature was 70°C, and the mixture was stirred continuously for 4 hours. The mixture was then irradiated with UV light to obtain the hydrogel component precursor.

[0054] The hydrogel component precursor was frozen in a freezer at -40°C for 3 hours and then thawed and stirred at room temperature. The freezing-thawing process was repeated 3 times to finally obtain the double-network hydrogel component-1.

[0055] Amphoteric monomers (dodecyl ethoxysulfonate betaine), carboxyl-terminated monomers (acrylic acid), free radical initiators (azobisisobutyronitrile), quaternary ammonium chitosan, and modified micro / nanoparticles were sequentially added to an ethanol-water solution. The reaction environment was a nitrogen atmosphere, the reaction temperature was 70°C, and the mixture was stirred continuously for 4 hours. The mixture was then irradiated with UV light to obtain the hydrogel component precursor.

[0056] The hydrogel component precursor was frozen in a freezer at -40°C for 3 hours and then thawed and stirred at room temperature. This freezing-thawing process was repeated 3 times to finally obtain hydrogel component-2, which is a dual-network doped with modified nanoparticles.

[0057] 1.3 Preparation of an antibacterial and low-ice-adhesion anti-icing coating

[0058] Antifreeze oil (glycerin) and antimicrobial peptide (cephalosporin) were mixed in proportion and stirred for 4 hours to obtain an antimicrobial lubricant.

[0059] A dual-network hydrogel component was applied to the substrate surface and dried. The substrate was then completely immersed in an antibacterial lubricant and allowed to stand for 48 hours to allow the lubricant to fully penetrate the hydrogel component, resulting in an antibacterial and low-ice-adhesion anti-icing coating. Subsequently, before testing, the substrate was held at a 45° angle to the horizontal for several minutes to remove excess lubricant from the surface, yielding sample coating-1 and sample coating-2 doped with modified nanoparticles.

[0060] 2. Material Characterization

[0061] 2.1 Antibacterial properties of the sample coating

[0062] Using an uncoated substrate surface as a control sample, contact plate experiments were conducted on the control sample and sample coating-1 with Bacillus ferrooxidans and Bacillus thiooxidans. Figure 1 This is a bar chart of the coating experiment results. The chart shows that coating-1 has a strong antibacterial effect against both *Bacillus ferrooxidans* and *Bacillus thiooxidans*, effectively and continuously killing corrosive bacteria on the substrate surface, inhibiting bacterial growth, and protecting the substrate from bacterial corrosion.

[0063] 2.2 Hydrophobic and anti-icing adhesion properties of the sample coating

[0064] A water droplet adhesion experiment was conducted on sample coating-2, and the morphology and adhesion of water droplets on the sample coating surface were recorded by video observation.

[0065] In the water droplet adhesion experiment, the hydrostatic contact angle and roll-off angle of sample coating-2 were approximately 152° and 4.9°, respectively, indicating superhydrophobicity. When a needle was used to contact a water droplet on the surface of the sample coating, the water droplet was easily carried away by the needle and did not adhere to the coating surface. This shows that the modified nanoparticles of sample coating-2 prepared in this embodiment can form superhydrophobic micro-nano structures on the coating surface, thereby preventing the adhesion of surface water droplets and thus inhibiting ice crystal adhesion.

[0066] Sample coating-1, sample coating-2, and an uncoated substrate were placed in a temperature-controlled container and then cooled to 0℃, -10℃, -20℃, -30℃, and -40℃, respectively. Specifically, a liftable platform was placed in the temperature-controlled container to hold the substrate, and liquid nitrogen was placed below the platform for cooling. The temperature was controlled by adjusting the distance between the lifting platform and the liquid nitrogen device. After adjusting the lifting platform to a suitable height and waiting for the substrate on the platform to reach the same temperature as the surrounding environment, an ice block of the same size (10mm*10mm*10mm) was placed on the substrate and held for 10 minutes. Then, the lifting platform was slowly tilted to one side, and the angle of tilt of the platform when the ice block slid was recorded as the sliding angle.

[0067] Figure 2 This is a line graph showing the relationship between the ice cube sliding angle of the sample coating and temperature. Since the uncoated substrate could not slide at -20°C, it was not included in the calculation. Figure 2 Enter the data of the substrate without a coating.

[0068] like Figure 2 As shown, the sliding angles of both sample coating-1 and sample coating-2 increase as the temperature decreases. However, the minimum sliding angles of sample coating-1 and sample coating-2 are also smaller than those of the uncoated substrate (about 5 degrees). This is because the water-lubricating layer formed on the surface of the sample coating, which has a lower freezing point, can work synergistically with the antifreeze oil to reduce ice adhesion. Therefore, ice blocks are easier to slide off the surface of the sample coating.

[0069] Furthermore, the sliding angles of sample coating-1 and sample coating-2 increased at a relatively slow rate, and even when the ambient temperature reached -40°C, the rate of increase in the sliding angle of sample coating-1 and sample coating-2 actually decreased, and the ice did not adhere to the surface of the sample coating. This is because the hydrogel component in the sample coating prepared in this embodiment and the precipitated antifreeze oil synergistically lower the freezing point of water on the coating surface, continuously generating a water-lubricating layer on the contact surface between the ice and the coating, inhibiting ice adhesion, and maintaining excellent anti-icing performance at low temperatures.

[0070] 2.3 Damping performance

[0071] The sample coating-1 was clamped in a dynamic thermomechanical analyzer, with a test frequency of 1 Hz, a heating rate of 3 ℃ / min, and a temperature range of -30 ℃ to 40 ℃.

[0072] Figure 3 The tanδ-T of the sample coating-1 obtained in the experiment is... g A line graph showing the relationship. For example... Figure 3 As shown, the tanδ of sample coating-1 max =0.80, tanδ max The corresponding T g Its temperature is -12.1℃. It can maintain high damping absorption performance even in low-temperature environments.

[0073] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An antibacterial and anti-icing coating, characterized in that, The product includes a surface layer composed of a hydrogel component and an antimicrobial lubricant. The hydrogel component comprises an interpenetrating double-network hydrogel composed of a zwitterionic polymer and chitosan, wherein the chitosan forms a physically cross-linked sacrificial network, and the antimicrobial lubricant includes antimicrobial peptides. The zwitterionic polymer is prepared by free radical copolymerization of zwitterionic monomers and carboxyl-terminated monomers. The antibacterial lubricant also includes antifreeze oil, which is one or more of glycerin, ethylene glycol, and derivatives of glycerin or ethylene glycol. The antimicrobial peptides include: Immobilize the antimicrobial peptide and couple it to the chitosan; Free antimicrobial peptides are dispersed in the antifreeze oil; The zwitterionic polymer and chitosan are mixed to form a hydrogel precursor solution, which is then subjected to multiple freeze-thaw cycles to form a double-network hydrogel component. The antimicrobial peptide is cephalosporin, and the molar ratio of the antimicrobial peptide to the chitosan is 1:1-3:

1. The molar ratio of the antifreeze oil to the antimicrobial peptide is 5:1-2:

1.

2. The antibacterial and anti-icing coating as described in claim 1, characterized in that, The zwitterionic monomer is one or more of dodecyl ethoxysulfonate betaine, carboxylate betaine methacrylate, and 2-methacryloyloxyethyl phosphorylcholine, and the terminal carboxyl monomer is one or more of methacrylic acid, acrylic acid, and undecenoic acid.

3. The antibacterial and anti-icing coating as described in claim 2, characterized in that, The zwitterionic monomer is dodecyl ethoxysulfonate betaine, the terminal carboxyl monomer is acrylic acid, and the free radical initiator is azobisisobutyronitrile.

4. The antibacterial and anti-icing coating as described in claim 1, characterized in that, It also includes modified nanoparticles, which are made by combining inorganic nanoparticles with biohydrophobic materials, wherein the biohydrophobic materials include rosin or rosin derivatives.

5. The antibacterial and anti-icing coating as described in claim 1, characterized in that, The antimicrobial peptide is dispersed in the antifreeze oil to form an antimicrobial lubricant, and the surface layer is prepared by immersing the hydrogel component in the antimicrobial lubricant and allowing it to stand for at least 24 hours.

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