A long-acting antioxidant intelligent targeted nano antifouling agent and its preparation method

Abstract

The present invention discloses a long-acting antioxidant intelligent targeted nano antifouling agent and a preparation method thereof, belonging to the field of marine biofouling protection. Through electrostatic interaction, a fouling-sensitive responsive polymer is self-assembled onto the surface of an inorganic nano-functional core. The fouling-sensitive responsive polymer is sodium polyacrylate and polyarginine, and the surface of the inorganic nano-functional core is metal oxide nanoparticles. Sodium polyacrylate and polyarginine are alternately self-assembled on the surface of the metal oxide nanoparticles. Each time sodium polyacrylate and polyamino acid are alternately self-assembled, a layer of fouling-sensitive responsive polymer is coated on the inorganic nano-functional core until a complete fouling-sensitive polymer shell is formed on the surface of the inorganic nano-functional core. The preparation process of the present invention is simple, fast, safe and non-toxic, meeting the development requirements of environmental friendliness; for biological fouling, the nano antifouling agent of the present invention has intelligent targeted release, with short-term recognition and long-acting bactericidal functions.

Description

Technical Field

[0001] The invention belongs to the field of marine biofouling protection, and specifically relates to a long-acting antioxidant intelligent targeted nano antifouling agent and a preparation method thereof. Background Art

[0002] As an important part of my country's shipping, the carrying capacity and navigation speed of ships play a key role in the development of the national economy. However, due to the anchoring of ships in shallow waters and the long-term navigation in offshore waters, marine organisms with strong adhesion in the marine environment, such as native spores, bacteria, seaweed and mussels, will firmly attach to the outer surface of the ship. On the one hand, the attachment of marine biological fouling will increase the friction resistance of the ship's navigation, shorten the life of the ship's hardware, increase fuel consumption, and cause environmental damage; on the other hand, the biofilm formed on the metal surface of the ship can absorb electrons through the extracellular electron transport chain, causing serious oxidative corrosion to the ship and other underwater buildings and facilities. In order to avoid the above negative behaviors, the main solution at this stage is to apply antifouling paint to prevent biological fouling.

[0003] Based on its efficient bactericidal and antifouling effects, the antifouling agent-releasing antifouling coating has won the favor of a large number of users. The most common nano antifouling agents at present include metal nanoparticles (such as Ag, Au, Cu2O, Ti2O, and ZnO), inorganic nano substances (such as carbon quantum dots, halloysite nanotubes, and carbon nanotubes), and biomass nano substances (such as lignin and cellulose). However, due to the poor component compatibility between substances with different physical and chemical properties, nano antifouling agents usually exhibit significant aggregation and "burst release" phenomena in the polymer matrix, which will have an adverse impact on the ecosystem and environmental safety. To solve the above problems, the use of surface and interface engineering technology to modify the surface of nano substances can significantly improve the integrity, durability, and long-term antifouling performance of antifouling coatings. The article "Preparation and properties of polyvinylpyrrolidone-cuprous oxide microcapsule antifouling coating" published by T. MAO, G. Lu, C. Xu, etc. in 《Progress in Organic Coatings》(2020, 141) discloses the synthesis of polyvinylpyrrolidone-Cu2O microcapsules by the single-step concentration method of sodium sulfate reduction. Secondly, a hydrophilic polyurethane / epoxy resin (PU / EP) coating is grafted and prepared by a two-step polymerization method using 2,4-toluene diisocyanate, polyethylene glycol monomethyl ether, and epoxy resin as raw materials. Among them, the polyvinylpyrrolidone-Cu2O microcapsules are used as antifouling agents, and the PU / EP coating is used as the coating matrix. Thanks to the effective coating of the polar substance polyvinylpyrrolidone on the Cu2O nanoparticles, the prepared composite antifouling coating has good colloidal particle dispersibility and system stability, and the release rate of its antifouling agent is reduced to 11.5 μg·cm -2 ·d -1 . The panel test in the shallow sea area shows that the polyvinylpyrrolidone-Cu2O-PU / EP coating has an extended antifouling time. Chinese Patent CN114806371A discloses that the sodium zirconium phosphate inorganic antibacterial agent loaded with Ag NPs is uniformly dispersed in organic resins such as silicone resin, fluorocarbon resin, styrene-acrylic emulsion, silicone-acrylic emulsion, and polyurethane. Based on the good component compatibility of the inorganic antibacterial agent and the resin matrix, the prepared antibacterial coating can form a uniform film on the surface of various substrates and has excellent adhesion strength. Sodium zirconium phosphate has a large specific surface area and has good adsorption and loading rates for Ag NPs. Based on the above structural characteristics, Ag ions can maintain a slow and stable release rate in the solution medium and have excellent and lasting antibacterial properties against both Gram-negative bacteria and Gram-positive bacteria. The mechanical strength of the coating is significantly improved due to the introduction of the sodium zirconium phosphate inorganic antibacterial agent.

[0004] The above technologies can achieve the uniform dispersion of antifouling agents in coatings. The excellent interfacial encapsulation effect can effectively delay the release rate of antifouling agents in antifouling coatings. However, the synthesis of the above nano-antifouling agents usually adopts traditional wet chemical synthesis processes, which are cumbersome and complex, and are not conducive to the efficient preparation and popularization of nano-antifouling agents. On the other hand, the release mechanism of the current slow-release technology mainly relies on diffusion. After the prepared composite nano-antifouling coating is placed in a water medium, this process has a weak correlation with external factors such as the pH, temperature, and degree of marine biofouling in the local area. With the extension of the service time, the nano-antifouling agent will still be exhausted, resulting in the failure of the coating. At present, China is mass-producing large ships with long maintenance intervals and high navigation efficiency, so the coatings used need to have many advantages such as excellent mechanical strength, intelligent responsiveness, and long-term antifouling. However, the release rate of the antifouling agent in the currently prepared antifouling coatings has a poor correlation with the growth level of fouling organisms in the marine environment. Even in seasons or sea areas where there is no or slight marine biofouling, the antifouling agent still continuously releases from the coating, without strict controllability. Serious raw material waste results in the fact that the antifouling coating cannot meet the current long-term controlled release requirements of the antifouling agent. Summary of the Invention

[0005] Aiming at the urgent need of ships and many underwater functional structures for the prevention and control efficiency of marine biofouling, and problems such as the weak long-term antifouling efficacy of the antifouling agent in the currently prepared antifouling coatings and the cumbersome and complex process steps, the research purpose of the present invention is to provide a long-term antioxidant intelligent targeted nano-antifouling agent and its preparation method. The biomass protease secreted by marine biofouling can efficiently catalyze and decompose polyamino acid substances such as polylysine, polyglycine, and polyarginine. Polyamino acid substances can be instantaneously decomposed in the fouling environment and remain stable in ordinary seawater media, with sensitive fouling recognition responsiveness and targeted functionality, achieving the regulation effect of the release rate of the antifouling agent adaptively with seasonal changes in biofouling attachment, increasing the antifouling efficiency and service life of the antifouling coating, and realizing long-term antifouling during the actual sea service process.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention provides a preparation method of a long-term antioxidant intelligent targeted nano-antifouling agent. By electrostatic interaction, a fouling-sensitive responsive polymer is self-assembled onto the surface of an inorganic nano-functional core. The fouling-sensitive responsive polymer is sodium polyacrylate and polyarginine, and the surface of the inorganic nano-functional core is metal oxide nanoparticles. Sodium polyacrylate and polyarginine are alternately self-assembled on the surface of the metal oxide nanoparticles. Each time sodium polyacrylate and polyamino acid are alternately self-assembled, a layer of fouling-sensitive responsive polymer is coated on the inorganic nano-functional core until a complete fouling-sensitive polymer shell is formed on the surface of the inorganic nano-functional core.

[0008] Furthermore, for the preparation method of the long-acting antioxidant intelligent targeted nano antifouling agent, a dry grinding process is adopted. Sodium polyacrylate and polyarginine are alternately added to the metal oxide nanoparticle powder, and ground and mixed evenly. The surface of the metal oxide nanoparticles is alternately self-assembled to cover with a sodium polyacrylate and polyarginine shell, obtaining the long-acting antioxidant intelligent targeted nano antifouling agent.

[0009] Furthermore, the metal oxide nanoparticles are Cu2O, and the average particle size of the Cu2O nanoparticles is 50±5.5 nm.

[0010] Furthermore, the average molecular weight of sodium polyacrylate is 3000 - 5000, and the average molecular weight of polyarginine is 30000 - 35000.

[0011] Furthermore, the addition amount of sodium polyacrylate and polyarginine each time is 6% - 10% of the mass of the metal oxide nanoparticles.

[0012] Furthermore, the number of grinding times for alternately adding sodium polyacrylate and polyarginine is 4 - 6 times.

[0013] Furthermore, each time sodium polyacrylate and polyarginine are added, they are ground for 8 - 12 minutes respectively.

[0014] The present invention also provides a long-acting antioxidant intelligent targeted nano antifouling agent, which is prepared by using the preparation method of the long-acting antioxidant intelligent targeted nano antifouling agent. The antifouling agent is a composite inorganic-organic nano antifouling agent with a core-shell structure, and is composed of an inorganic nano-functional core and a fouling-sensitive polymer shell coating it;

[0015] The inorganic nano-functional core is Cu2O nanoparticles;

[0016] The fouling-sensitive polymer shell is alternately composed of sodium polyacrylate and polyarginine.

[0017] Furthermore, the average particle size of the long-acting antioxidant intelligent targeted nano antifouling agent is 55.1±0.7 nm - 60.3±0.8 nm. After being uniformly dispersed in water, the hydrodynamic radius distribution range is 255±2.7 nm - 333±6.4 nm, and the Zeta potential distribution range is 19.51 eV - 34.63 eV.

[0018] The present invention also provides an application of the long-acting antioxidant intelligent targeted nano antifouling agent in marine equipment, which is used as an antifouling coating for marine engineering equipment to meet the long-term service requirements.

[0019] Compared with the prior art, the long-acting antioxidant intelligent targeted nano antifouling agent and its preparation method of the present invention have the following beneficial effects:

[0020] The present invention realizes the alternate layer-by-layer self-assembly of sodium polyacrylate and polyarginine on the surface of metal oxide nanoparticles through a dry grinding process, and efficiently prepares metal oxide nanoparticles@sodium polyacrylate / polyarginine, namely a composite long-acting antioxidant intelligent targeted nano antifouling agent. The preparation process is simple and fast, safe and non-toxic, meeting the requirements of environmentally friendly development. Due to the electrostatic attraction between the polymer and the inorganic nano antifouling agent, the present invention does not require a cross-linking agent. Based on the full protection of the metal oxide nanoparticles by the sodium polyacrylate / polyarginine composite polymer shell, the nano antifouling agent of the present invention has good antioxidant properties, stability and durability. Based on the biological protease catalytic decomposition characteristics of the polyarginine shell, the nano antifouling agent of the present invention has sensitive and efficient intelligent targeted release of biological fouling, ensuring the short-term recognition and long-term bactericidal function of the nano antifouling agent. Therefore, the nano antifouling agent of the present invention can make targeted release rate regulation according to the change law of marine biological fouling degree with the off-season / peak season, realizing the intelligent and controllable release of the nano antifouling agent according to the external environment changes (pH, temperature and biological adhesion degree), and prolonging the antifouling coating period. Based on the alternate self-assembly layers of sodium polyacrylate / polyarginine, the nano antifouling agent of the present invention has good dispersibility, stability and antibacterial properties. Brief Description of the Drawings

[0021] Figure 1 It is a schematic diagram of the preparation and action principle of a long-acting antioxidant intelligent targeted nano antifouling agent of the present invention;

[0022] Figure 2 It is a TEM morphology diagram of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in Example 1 of the present invention after being uniformly dispersed in an aqueous solution and tested by transmission electron microscopy (TEM);

[0023] Figure 3 It is a hydrodynamic particle size distribution diagram of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in Example 1 of the present invention after being uniformly dispersed in an aqueous solution;

[0024] Figure 4 It is a Zeta potential diagram of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in Example 1 of the present invention after being uniformly dispersed in an aqueous solution;

[0025] Figure 5 It is a diagram of the real-time tracking of the self-assembly process of the polymer on the outer surface of Cu2O nanoparticles by a quartz microelectromechanical balance (QCM) in Example 2 of the present invention;

[0026] Figure 6 It is a TEM morphology diagram of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in Example 2 of the present invention after being uniformly dispersed in an aqueous solution and tested by transmission electron microscopy (TEM);

[0027] Figure 7Hydrodynamic particle size distribution diagram of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in Example 2 of the present invention after being uniformly dispersed in an aqueous solution;

[0028] Figure 8 Zeta potential diagram of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in Example 2 of the present invention after being uniformly dispersed in an aqueous solution;

[0029] Figure 9 TEM morphology diagram of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in Example 3 of the present invention after being uniformly dispersed in an aqueous solution and tested by transmission electron microscopy (TEM);

[0030] Figure 10 Hydrodynamic particle size distribution diagram of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in Example 3 of the present invention after being uniformly dispersed in an aqueous solution;

[0031] Figure 11 Zeta potential diagram of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in Example 3 of the present invention after being uniformly dispersed in an aqueous solution;

[0032] Figure 12 TEM morphology diagram of Cu2O nanoparticles in Comparative Example 1 of the present invention after being uniformly dispersed in an aqueous solution and tested by transmission electron microscopy (TEM). Detailed implementation manners

[0033] The present invention will be described in detail below with reference to the embodiments.

[0034] To further elaborate on the technical means and related effects adopted by the present invention to achieve the predetermined invention purpose, the following describes in detail the specific implementation process, morphological structure, physical and chemical properties, and actual effects of the present invention application with reference to the preferred embodiments and the corresponding drawings.

[0035] The experimental methods without specific conditions are usually carried out under conventional conditions, such as those described in textbooks and experimental guides, or according to the conditions recommended by the manufacturer, which are well-known or easily accessible to those of ordinary skill in the art. The following embodiments are only the preferred embodiments of the present invention and do not limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

[0036] The embodiments of the present invention provide a preparation method of a long-acting antioxidant intelligent targeted nano antifouling agent, including the following steps:

[0037] Adopt a dry grinding process, and self-assemble the fouling-sensitive responsive polymers (sodium polyacrylate and polyarginine) onto the surface of the inorganic nano-functional core (Cu2O nanoparticles) through electrostatic interaction. Alternately self-assemble sodium polyacrylate and polyarginine on the surface of the Cu2O nanoparticles. Each time sodium polyacrylate and polyamino acid are alternately self-assembled, a layer of fouling-sensitive responsive polymer is coated on the inorganic nano-functional core until a complete fouling-sensitive responsive polymer shell is formed on the surface of the inorganic nano-functional core, obtaining a long-acting antioxidant intelligent targeted nano antifouling agent; Subsequently, the successfully prepared nano antifouling agent is placed in a vacuum sealing bag, and after evacuating the air, it is sealed and stored. As Figure 1 shown, in the present invention, due to sodium polyacrylate being negatively charged, polyarginine being positively charged, and Cu2O nanoparticles being positively charged, sodium polyacrylate and polyarginine are alternately self-assembled onto the surface of the Cu2O nanoparticles through electrostatic interaction to prepare a long-acting antioxidant intelligent targeted nano antifouling agent. After the nano antifouling agent is dispersed in an aqueous solution, under the action of extracellular protease, the polyarginine component undergoes hydrolysis, resulting in the cleavage of the polymer shell of the nano antifouling agent, triggering the controllable release of Cu 2+ in the solution and playing an antifouling role. In the present invention, the metal oxide nanoparticles used as the inorganic nano-functional core can also be extended to ZnO or Sn2O, etc.

[0038] The present invention is further illustrated by the following specific examples:

[0039] Example 1

[0040] A preparation method of a long-acting antioxidant intelligent targeted nano antifouling agent of the present invention includes the following steps:

[0041] Weigh 0.1 g of Cu2O nanoparticle powder with a particle size of 50 ± 5.5 nm and place it in a crucible as the raw material. Add sodium polyacrylate (average molecular weight: 3000) accounting for 8% by mass of the Cu2O nanoparticles to the crucible containing the Cu2O nanoparticle powder and grind for 12 min to make the Cu2O nanoparticle powder and the sodium polyacrylate powder evenly mixed; Subsequently, add polyarginine powder (average relative molecular weight: 30000) accounting for 8% by mass of the Cu2O nanoparticles to the mixture and grind for 12 min to make the above powder mixture evenly mixed. This process is regarded as modifying a layer of fouling-sensitive responsive polymer shell on the surface of the Cu2O nanoparticles. Alternately cover sodium polyacrylate and polyarginine 4 times to prepare an orange-yellow Cu2O nanoparticle@ sodium polyacrylate / polyarginine composite nano antifouling agent containing 4 layers of fouling-sensitive responsive polymers, that is, a long-acting antioxidant intelligent targeted nano antifouling agent.

[0042] Performance analysis:

[0043] Analyze the dispersibility, stability, antioxidant property, and intelligent targeting property of the long-acting antioxidant intelligent targeting nano antifouling agent in this embodiment;

[0044] (1) Dispersibility analysis:

[0045] Add the powder of the long-acting antioxidant intelligent targeting nano antifouling agent prepared in this embodiment into water, use water as the dispersant, and form a uniform and stable orange-yellow nano colloidal solution through ultrasonic dispersion;

[0046] Drop 20 μL of the prepared orange-yellow nano colloidal solution onto the surface of a molybdenum grid, place it in an oven at 50 °C for 1 h to prepare a TEM sample, and conduct TEM morphology detection. Compared with the apparent characteristics of inorganic nanoparticles, as Figure 2 shown, the surface blackness of the nano antifouling agent prepared in this embodiment decreases and is scattered in the field of view. It can be seen that the sodium polyacrylate-polyarginine polymer shell has been successfully coated on the outside of the Cu2O nanoparticles, and the prepared nano antifouling agent is uniformly dispersed in water; use Image J software for statistics, and the average particle size of the long-acting antioxidant intelligent targeting nano antifouling agent of the present invention is 55.5 ± 1.5 nm;

[0047] Test the particle size distribution (DLS) of the nano antifouling agent in the orange-yellow nano colloidal solution by a nano particle size analyzer, as Figure 3 shown, the measured hydrodynamic average radius is 260 ± 5.4 nm, further indicating that the long-acting antioxidant intelligent targeting nano antifouling agent of the present invention has good hydration and dispersibility in the water medium.

[0048] (2) Antioxidant property and stability analysis:

[0049] Add the powder of the long-acting antioxidant intelligent targeting nano antifouling agent prepared in this embodiment into water, use water as the dispersant, and form a uniform and stable orange-yellow nano colloidal solution through ultrasonic dispersion;

[0050] Conduct Zeta potential test on the uniform and stable orange-yellow nano colloidal solution, as Figure 4 shown, the Zeta potential is 34.63 eV, indicating that the long-acting antioxidant intelligent targeting nano antifouling agent of the present invention has good stability;

[0051] Let the uniform and stable orange-yellow nano colloidal solution stand in the air environment for 7 days, observe the change of the apparent morphology, and find that the colloidal solution system is still uniformly dispersed and the color remains the initial orange-yellow, indicating that the long-acting antioxidant intelligent targeting nano antifouling agent of the present invention has good stability, which is mainly due to the protection of the polymer shell.

[0052] (3) Intelligent targeting property analysis:

[0053] Analyze the intelligent targeting property of the long-acting antioxidant intelligent targeting nano antifouling agent prepared in this example through a normal liquid environment and a simulated biofouling environment;

[0054] The normal liquid environment medium refers to culturing Escherichia coli with an initial bacterial concentration of 10 6 CFU / mL in 2216E liquid medium at a temperature of 37°C; the simulated biofouling environment medium is to co-culture Escherichia coli with an initial bacterial concentration of 10 6 CFU / mL and protease in 2216E liquid medium at a temperature of 37°C, because marine biofouling secretes biogenic protease;

[0055] Add the long-acting antioxidant intelligent targeting nano antifouling agent prepared in this example to the normal liquid environment medium and the simulated biofouling environment medium respectively. Among them, the polyarginine shell can be specifically catalytically decomposed when contacting with protease, so it can accelerate the release rate of its internal Cu 2+ . After detection by inductively coupled plasma spectrometer (ICP), the concentration of Cu 2+ in the normal liquid environment medium is about 81±3 mg / L, while the concentration of Cu 2+ in the simulated biofouling environment medium is about 185±2 mg / L; on the other hand, in microbiological research, OD 600nm can usually reflect the bacterial concentration of bacteria. It can be measured by ultraviolet spectrophotometer that the OD 600nm in the supernatant drops from 0.58 in the normal liquid environment medium to 0.52 in the simulated fouling environment; from the above test results, it can be seen that due to the introduction of biogenic protease, polyarginine decomposes immediately in the biofouling environment, promoting the release of more Cu 2+ , achieving a more excellent antibacterial effect; on the contrary, the polyarginine shell remains stable in the normal liquid environment, and the release concentration of Cu 2+ is relatively small. Therefore, the nano antifouling agent of the present invention has sensitive fouling recognition responsiveness and targeting functionality. Utilizing the intelligent response release effect of the nano antifouling agent of the present invention can ensure the maintenance of its long-acting antifouling performance and provide a key functional component for the development of intelligent long-acting antifouling and anticorrosion coatings in marine engineering.

[0056] Example 2

[0057] Weigh 1 g of Cu2O nanoparticle powder with a particle size of 50 ± 5.5 nm and place it in a crucible as the raw material. Add sodium polyacrylate (average molecular weight: 5000) accounting for 10% by mass of the Cu2O nanoparticles to the crucible containing the Cu2O nanoparticle powder, and grind for 10 min to uniformly mix the Cu2O nanoparticle powder and the sodium polyacrylate powder. Subsequently, add polyarginine powder (average relative molecular weight: 35000) accounting for 10% by mass of the Cu2O nanoparticles to the mixture, and grind for 10 min to uniformly mix the above powder mixture. This process is regarded as modifying 1 layer of fouling-sensitive responsive polymer shell. Alternately cover sodium polyacrylate and polyarginine 6 times to prepare Cu2O nanoparticles@ sodium polyacrylate / polyarginine composite nano antifouling agent containing 6 layers of fouling-sensitive responsive polymer, that is, a long-acting antioxidant intelligent targeted nano antifouling agent.

[0058] As Figure 5 shown, in this example, a quartz crystal microbalance (QCM) is used to analyze and study the specific process of the alternate layer-by-layer self-assembly of sodium polyacrylate and polyarginine on the surface of Cu2O nanoparticles 6 times; it can be seen from the figure that whenever the deposition step of sodium polyacrylate or polyarginine is carried out, the fundamental frequency will decrease significantly. In the QCM test, the decrease in the fundamental frequency usually indicates that a substance is deposited on the crystal surface; thus, it can be known that sodium polyacrylate and polyarginine have been successfully deposited on the surface of Cu2O nanoparticles, and this layer-by-layer change mode effectively reflects the typical characteristics of the layer-by-layer self-assembly process;

[0059] Using the Sauerbrey equation, not only can the deposition mass of sodium polyacrylate and polyarginine be quantitatively analyzed each time, but also the frequency change is related to the mass change per unit area. According to the Sauerbrey equation, the change in the crystal frequency is proportional to the deposition mass, and the change in the deposited mass (Δ m ) can be calculated by the following formula:

[0060] ;

[0061] where, Δ f is the frequency change (in Hz), C is the constant in the Sauerbrey equation (for a 5 MHz AT-cut quartz crystal, its value is approximately 17 ng / (cm²·Hz)), n is the harmonic number (for the fundamental frequency, n = 1);

[0062] In this invention, it is assumed that the harmonic number is 1, and the change in the deposited mass is calculated by the following formula:

[0063] ;

[0064] It can be calculated that in a single deposition step, the mass change of polylysine is approximately 354 ng / cm²; the mass change of sodium polyacrylate in a single deposition step is approximately 230.1 ng / cm². These values not only accurately reflect the mass change of sodium polyacrylate and polylysine, but also indirectly reflect their successful deposition on the nanoparticle surface.

[0065] Performance analysis:

[0066] Add the long-acting antioxidant intelligent targeted nano antifouling agent powder prepared in this example to water, use water as a dispersant, and form a uniform and stable orange-yellow nano colloid by ultrasonic dispersion;

[0067] Drop 20 μL of the prepared orange-yellow nano colloid onto the surface of a molybdenum grid, place it in an oven at 50 °C for 1 h to prepare a TEM sample, and perform TEM morphology detection. As Figure 6 shown, it can be seen that the long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example can be uniformly dispersed in water, has good dispersibility, and is statistically analyzed using Image J software to obtain the average particle size of the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention as 60.3 ± 0.8 nm;

[0068] Test the particle size distribution (DLS) of the nano antifouling agent in the orange-yellow nano colloid by a nano particle size analyzer. As Figure 7 shown, the measured hydrodynamic average radius is 333 ± 6.4 nm, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good hydration and dispersibility;

[0069] Perform Zeta potential test on the prepared orange-yellow nano colloid. As Figure 8 shown, the Zeta potential is 19.51 eV, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good stability;

[0070] The intelligent targeting principle of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example is the same as the intelligent targeting analysis in Example 1.

[0071] Example 3

[0072] Weigh 0.5 g of Cu2O nanoparticle powder with a particle size of 50 ± 5.5 nm and place it in a crucible as the raw material. Add sodium polyacrylate (average molecular weight: 4000) accounting for 6% by mass of the Cu2O nanoparticles to the crucible containing the Cu2O nanoparticle powder, and grind for 10 min to uniformly mix the Cu2O nanoparticle powder and the sodium polyacrylate powder. Subsequently, add polyarginine powder (average relative molecular weight: 33000) accounting for 6% by mass of the Cu2O nanoparticles to the mixture, and grind for 10 min to uniformly mix the above powder mixture. This process is regarded as modifying 1 layer of fouling-sensitive responsive polymer shell. Alternately cover sodium polyacrylate and polyarginine 5 times to prepare Cu2O nanoparticles @ sodium polyacrylate / polyarginine composite nano antifouling agent containing 5 layers of fouling-sensitive responsive polymer, that is, a long-acting antioxidant intelligent targeted nano antifouling agent.

[0073] Add the long-acting antioxidant intelligent targeted nano antifouling agent powder prepared in this example to water, use water as a dispersant, and form a uniform and stable orange-yellow nano colloid by ultrasonic dispersion;

[0074] Drop 20 μL of the prepared orange-yellow nano colloid onto the surface of a molybdenum grid, place it in an oven at 50 °C for 1 h to prepare a TEM sample, and conduct TEM morphology detection. As Figure 9 shown, it can be seen that the long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example can be uniformly dispersed in water, has good dispersibility, and is statistically analyzed using image J software to obtain the average particle size of the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention as 55.1 ± 0.7 nm.

[0075] Test the particle size distribution (DLS) of the nano antifouling agent in the orange-yellow nano colloid by a nano particle size analyzer. As Figure 10 shown, the measured hydrodynamic average radius is 255 ± 2.7 nm, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good hydration and dispersibility;

[0076] Conduct Zeta potential test on the prepared orange-yellow nano colloid. As Figure 11 shown, the Zeta potential is 30.25 eV, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good stability;

[0077] The intelligent targeting principle of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example is the same as the intelligent targeting analysis in Example 1.

[0078] Example 4

[0079] Weigh 0.4 g of Cu2O nanoparticle powder with a particle size of 50 ± 5.5 nm and place it in a crucible as the raw material. Add sodium polyacrylate (average molecular weight: 3500) with a mass ratio of 6% of the Cu2O nanoparticles to the crucible containing the Cu2O nanoparticle powder, and grind for 8 min to uniformly mix the Cu2O nanoparticle powder and the sodium polyacrylate powder. Subsequently, add polyarginine powder (average relative molecular weight: 32000) with a mass ratio of 6% of the Cu2O nanoparticles to the mixture, and grind for 8 min to uniformly mix the above powder mixture. This process is regarded as coating 1 layer of fouling-sensitive responsive polymer shell. Alternately cover sodium polyacrylate and polyarginine 6 times to prepare Cu2O nanoparticles@ sodium polyacrylate / polyarginine composite nano antifouling agent containing 6 layers of fouling-sensitive responsive polymer, that is, long-acting antioxidant intelligent targeted nano antifouling agent.

[0080] Add the long-acting antioxidant intelligent targeted nano antifouling agent powder prepared in this example to water, use water as a dispersant, and form a uniform and stable orange-yellow nano colloid by ultrasonic dispersion;

[0081] Drop 20 μL of the prepared orange-yellow nano colloid onto the surface of a molybdenum grid, place it in an oven at 50 °C for 1 h to prepare a TEM sample, and conduct TEM morphology detection. The long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example can be uniformly dispersed in water, has good dispersibility, and is statistically analyzed using Image J software. The average particle size of the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention is 56.2 ± 2.5 nm.

[0082] Test the particle size distribution (DLS) of the nano antifouling agent in the orange-yellow nano colloid by a nano particle size analyzer. The measured hydrodynamic average radius is 283 ± 1.2 nm, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good hydration and dispersibility;

[0083] Perform Zeta potential test on the prepared orange-yellow nano colloid. The Zeta potential is 27.3 eV, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good stability;

[0084] The intelligent targeting principle of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example is the same as the intelligent targeting analysis in Example 1.

[0085] Example 5

[0086] Weigh 0.2 g of Cu2O nanoparticle powder with a particle size of 50 ± 5.5 nm and place it in a crucible as the raw material. Add sodium polyacrylate (average molecular weight: 4000) accounting for 7% by mass of the Cu2O nanoparticles to the crucible containing the Cu2O nanoparticle powder, and grind for 11 min to uniformly mix the Cu2O nanoparticle powder and the sodium polyacrylate powder. Subsequently, add polyarginine powder (average relative molecular weight: 34000) accounting for 7% by mass of the Cu2O nanoparticles to the mixture, and grind for 11 min to uniformly mix the above powder mixture. This process is regarded as modifying 1 layer of fouling-sensitive responsive polymer shell. Alternately cover sodium polyacrylate and polyarginine 5 times to prepare Cu2O nanoparticles @ sodium polyacrylate / polyarginine composite nano antifouling agent containing 5 layers of fouling-sensitive responsive polymer, that is, a long-acting antioxidant intelligent targeted nano antifouling agent.

[0087] Add the long-acting antioxidant intelligent targeted nano antifouling agent powder prepared in this example to water, use water as a dispersant, and form a uniform and stable orange-yellow nano colloid by ultrasonic dispersion;

[0088] Drop 20 μL of the prepared orange-yellow nano colloid onto the surface of a molybdenum grid, place it in an oven at 50 °C for 1 h to prepare a TEM sample, and conduct TEM morphology detection. The long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example can be uniformly dispersed in water, has good dispersibility, and is statistically analyzed using Image J software. The average particle size of the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention is 55.8 ± 3.4 nm.

[0089] Test the particle size distribution (DLS) of the nano antifouling agent in the orange-yellow nano colloid by a nano particle size analyzer. The measured hydrodynamic average radius is 276 ± 5.3 nm, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good hydration and dispersibility;

[0090] Conduct a Zeta potential test on the prepared orange-yellow nano colloid. The Zeta potential is 29.37 eV, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good stability;

[0091] The intelligent targeting principle of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example is the same as the intelligent targeting analysis in Example 1.

[0092] Example 6

[0093] Weigh 0.75 g of Cu2O nanoparticle powder with a particle size of 50 ± 5.5 nm and place it in a crucible as the raw material. Add sodium polyacrylate (average molecular weight: 4500) accounting for 9% by mass of the Cu2O nanoparticles to the crucible containing the Cu2O nanoparticle powder, and grind for 10 min to uniformly mix the Cu2O nanoparticle powder and the sodium polyacrylate powder. Subsequently, add polyarginine powder (average relative molecular weight: 31000) accounting for 9% by mass of the Cu2O nanoparticles to the mixture, and grind for 10 min to uniformly mix the above powder mixture. This process is regarded as modifying 1 layer of fouling-sensitive responsive polymer shell. Alternately cover sodium polyacrylate and polyarginine 6 times to prepare Cu2O nanoparticles@ sodium polyacrylate / polyarginine composite nano antifouling agent containing 6 layers of fouling-sensitive responsive polymer, that is, a long-acting antioxidant intelligent targeted nano antifouling agent.

[0094] Add the long-acting antioxidant intelligent targeted nano antifouling agent powder prepared in this example to water, use water as a dispersant, and form a uniform and stable orange-yellow nano colloid by ultrasonic dispersion;

[0095] Drop 20 μL of the prepared orange-yellow nano colloid onto the surface of a molybdenum grid, place it in an oven at 50 °C for 1 h to prepare a TEM sample, and conduct TEM morphology detection. The long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example can be uniformly dispersed in water, has good dispersibility, and is statistically analyzed using image J software. The average particle size of the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention is 59.1 ± 1.6 nm.

[0096] Test the particle size distribution (DLS) of the nano antifouling agent in the orange-yellow nano colloid by a nano particle size analyzer. The measured hydrodynamic average radius is 324 ± 7.4 nm, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good hydration and dispersibility;

[0097] Conduct a Zeta potential test on the prepared orange-yellow nano colloid. The Zeta potential is 21.03 eV, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good stability;

[0098] Analyze the intelligent targeting principle of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example in the same way as the intelligent targeting analysis in Example 1.

[0099] Example 7

[0100] Weigh 0.6 g of Cu2O nanoparticle powder with a particle size of 50 ± 5.5 nm and place it in a crucible as the raw material. Add sodium polyacrylate (average molecular weight: 3800) accounting for 7.5% by mass of the Cu2O nanoparticles to the crucible containing the Cu2O nanoparticle powder, and grind for 9 min to uniformly mix the Cu2O nanoparticle powder and the sodium polyacrylate powder. Subsequently, add polyarginine powder (average relative molecular weight: 30000) accounting for 7.5% by mass of the Cu2O nanoparticles to the mixture, and grind for 9 min to uniformly mix the above powder mixture. This process is regarded as modifying 1 layer of fouling-sensitive responsive polymer shell. Alternately cover sodium polyacrylate and polyarginine 5 times to prepare Cu2O nanoparticles @ sodium polyacrylate / polyarginine composite nano antifouling agent containing 5 layers of fouling-sensitive responsive polymer, that is, a long-acting antioxidant intelligent targeted nano antifouling agent.

[0101] Add the long-acting antioxidant intelligent targeted nano antifouling agent powder prepared in this example to water, use water as the dispersant, and form a uniform and stable orange-yellow nano colloid solution by ultrasonic dispersion;

[0102] Drop 20 μL of the prepared orange-yellow nano colloid solution onto the surface of a molybdenum grid, place it in an oven at 50 °C for 1 h to prepare a TEM sample, and conduct TEM morphology detection. The long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example can be uniformly dispersed in water, has good dispersibility, and is statistically analyzed using image J software to obtain the average particle size of the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention as 56.4 ± 1.6 nm.

[0103] Test the particle size distribution (DLS) of the nano antifouling agent in the orange-yellow nano colloid solution by a nano particle size analyzer. The hydrodynamic average radius measured is 292 ± 4.6 nm, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good hydration and dispersibility;

[0104] Conduct a Zeta potential test on the prepared orange-yellow nano colloid solution. The Zeta potential is 26.42 eV, indicating that the long-acting antioxidant intelligent targeted nano antifouling agent of the present invention has good stability;

[0105] The intelligent targeting principle of the long-acting antioxidant intelligent targeted nano antifouling agent prepared in this example is the same as the intelligent targeting analysis in Example 1.

[0106] Comparative Example 1

[0107] Only use Cu2O nanoparticles (particle size of 50 ± 5.5 nm) as the antifouling agent without modifying the polymer shell. Add it to water, use water as the dispersant, and form a uniform and stable orange-yellow nano colloid solution system by ultrasonic dispersion;

[0108] Drop 20 μL of the nano-glue solution onto the surface of the molybdenum grid, place it in an oven at 50 °C for 1 h to prepare a TEM sample, and perform TEM detection. As Figure 12 shown, it was found that the Cu2O nanoparticles underwent large-area aggregation. The overall appearance of the aggregates was black, and the dispersibility was poor.

[0109] After the nano-latex solution system was left static in the air environment for 7 days, the apparent morphological changes were observed. It was found that precipitation occurred completely at the bottom of the Cu2O nano-glue solution system, and the precipitate was black, further proving its poor antioxidant and stability.

[0110] Comparative Example 2

[0111] Use the Cu2O@polyvinylpyrrolidone nano-antifouling agent to perform intelligent targeting analysis through normal liquid environment and simulated biofouling environment;

[0112] The normal liquid environment medium refers to culturing Escherichia coli with an initial bacterial concentration of 10 6 CFU / mL in 2216E liquid medium at a temperature of 37 °C; the simulated biofouling environment medium is to co-culture Escherichia coli with an initial bacterial concentration of 10 6 CFU / mL and protease in 2216E liquid medium at a temperature of 37 °C because marine biofouling secretes biogenic protease;

[0113] Detected by inductively coupled plasma spectrometer (ICP), the Cu 2+ concentration in the normal liquid environment medium was about 78 ± 4 mg / L, and the Cu 2+ concentration in the simulated biofouling environment medium was about 76 ± 4 mg / L. On the other hand, in microbiological research, OD 600nm usually can reflect the bacterial concentration of bacteria. It was measured by ultraviolet spectrophotometer that OD 600nm The OD 600nm in the supernatant of the normal liquid environment medium and the simulated fouling environment were 0.60 and 0.61 respectively; the above test results showed no significant differences, indicating that the initial Cu2O@polyvinylpyrrolidone nano-antifouling agent did not have intelligent antifouling efficacy.

Claims

1. A method for preparing a long-lasting antioxidant intelligent targeted nano antifouling agent, characterized in that: The contamination-sensitive responsive polymer is self-assembled onto the surface of the inorganic nano-functional core through electrostatic interaction, wherein the contamination-sensitive responsive polymer is sodium polyacrylate and polyarginine, and the surface of the inorganic nano-functional core is metal oxide nanoparticles, and sodium polyacrylate and polyarginine are alternately self-assembled on the surface of the metal oxide nanoparticles, and each time sodium polyacrylate and polyarginine are alternately self-assembled, a layer of contamination-sensitive responsive polymer is coated on the inorganic nano-functional core until a complete contamination-sensitive polymer shell is formed on the surface of the inorganic nano-functional core; The metal oxide nanoparticles are Cu2O, and the average particle size of the Cu2O nanoparticles is 50±5.5 nm.

2. The method for preparing a long-acting antioxidant intelligent targeted nano antifouling agent according to claim 1, characterized in that: By using a dry grinding process, sodium polyacrylate and polyarginine are alternately added to the metal oxide nanoparticle powder, and the mixture is ground and mixed evenly. The surface of the metal oxide nanoparticles is alternately self-assembled to cover the sodium polyacrylate and polyarginine shells, thereby obtaining a long-lasting antioxidant intelligent targeted nano antifouling agent.

3. The method for preparing a long-acting antioxidant intelligent targeted nano antifouling agent according to claim 1, characterized in that: The average molecular weight of sodium polyacrylate is 3000-5000, and the average molecular weight of polyarginine is 30000-35000.

4. The method for preparing a long-acting antioxidant intelligent targeted nano antifouling agent according to claim 1, characterized in that: The amount of sodium polyacrylate and polyarginine added each time is 6%-10% of the mass of the metal oxide nanoparticles.

5. The method for preparing a long-acting antioxidant intelligent targeted nano antifouling agent as claimed in claim 4, characterized in that: The grinding times of alternately adding sodium polyacrylate and polyarginine are 4 to 6 times.

6. The method for preparing a long-acting antioxidant intelligent targeted nano antifouling agent according to claim 4, characterized in that: Sodium polyacrylate and polyarginine were added each time and ground for 8-12 minutes respectively.

7. A long-acting antioxidant intelligent targeted nano antifouling agent, prepared by the method for preparing a long-acting antioxidant intelligent targeted nano antifouling agent according to claim 1, characterized in that: The antifouling agent is a composite inorganic-organic nano antifouling agent with a core-shell structure, which is composed of an inorganic nano functional core and a fouling sensitive polymer shell coating the core; the inorganic nano functional core is Cu2O nanoparticles; the fouling sensitive polymer shell is composed of sodium polyacrylate and polyarginine alternately.

8. A long-acting antioxidant intelligent targeted nano antifouling agent as claimed in claim 7, characterized in that: The average particle size of the long-lasting antioxidant intelligent targeted nano antifouling agent is 55.1±0.7nm-60.3±0.8nm. After being uniformly dispersed in water, the hydrodynamic radius distribution range is 255±2.7nm-333±6.4nm, and the Zeta potential distribution range is 19.51eV-34.63eV.

9. An application of the long-acting antioxidant intelligent targeted nano antifouling agent according to any one of claims 7-8 in marine equipment, characterized in that: Used as antifouling coating for marine engineering equipment that meets long-term service requirements.

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