Water-based treatment agent and preparation method thereof

Abstract

The invention relates to the technical field of treatment agents, and provides a water-based treatment agent preparation method, which comprises: S100, preparing a nanoparticle dispersion liquid: adding nanoparticles and a dispersant into deionized water, and carrying out first ultrasonic treatment to obtain the nanoparticle dispersion liquid; s200, preparing a matrix resin emulsion: adding matrix resin and a curing agent into deionized water, and carrying out first stirring treatment to obtain the matrix resin emulsion; and S300, preparing the water-based treatment agent: adding the matrix resin emulsion into the nano-particle dispersion liquid, carrying out second stirring treatment, and sequentially adding the block copolymer, the hydrophobic microspheres, the cross-linking agent and the auxiliary agent in the second stirring treatment process to obtain the water-based treatment agent. By adding the block copolymer, the problem of compatibility between the hydrophobic microspheres and the matrix resin is solved, and the adhesion contradiction between the hydrophobic microspheres and the base material is avoided, so that the water-based treatment agent is more uniform, and the surface flatness and stability are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of treatment agents, and in particular to an aqueous treatment agent and a preparation method thereof. Background Art

[0002] Water-based treatment agents are a type of environmentally friendly chemicals that are mainly used in applications such as surface treatment, coatings, paints, adhesives, etc., usually with water as the solvent. This type of treatment agent is popular due to its low volatile organic compound (VOC) content. Water-based treatment agents are widely used in many industries, especially in the fields of coatings, adhesives, leather processing and textile processing.

[0003] Modern water-based treatment agents not only pursue basic adhesion and durability, but also gradually give them multiple functions such as antibacterial, hydrophobic, wear-resistant, and chemical-resistant to meet the needs of different materials and applications. However, in many fields, water-based treatment agents need to have both excellent hydrophobicity and high adhesion, but these two are often contradictory and difficult to balance. Summary of the invention

[0004] The present invention aims to solve at least one of the above technical problems.

[0005] To this end, the first object of the present invention is to provide a method for preparing an aqueous treatment agent.

[0006] A second object of the present invention is to provide an aqueous treatment agent.

[0007] To achieve the first object of the present invention, the present invention provides a method for preparing an aqueous treatment agent, comprising:

[0008] S100, preparing a nanoparticle dispersion: adding nanoparticles and a dispersant into deionized water and performing a first ultrasonic treatment to obtain a nanoparticle dispersion;

[0009] S200, preparing a base resin emulsion: adding a base resin and a curing agent into deionized water for a first stirring treatment to obtain a base resin emulsion;

[0010] S300, preparing a water-based treatment agent: adding a base resin emulsion to a nanoparticle dispersion for a second stirring treatment, and sequentially adding a block copolymer, a hydrophobic microsphere, a crosslinking agent, and an auxiliary agent during the second stirring treatment to obtain a water-based treatment agent;

[0011] The matrix resin includes polyaspartic acid resin and modified hydroxypropyl acrylate; the hydrophobic microspheres are polydopamine microspheres loaded with hydrophobic substances.

[0012] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: the water-based treatment agent of the present invention adopts polyaspartic acid resin and modified hydroxypropyl acrylate as the matrix resin, which not only provides excellent adhesion but also enhances the flexibility of the coating; the polyaspartic acid resin gives the coating higher mechanical strength and wear resistance, and the modified hydroxypropyl acrylate enhances the flexibility and adaptability of the water-based treatment agent, and is particularly suitable for coating applications on surfaces of different materials; the dispersant and ultrasonic treatment ensure the uniform dispersion of the nanoparticles, avoid the sedimentation and agglomeration of the particles, so that the nanoparticles can improve the wear resistance, UV resistance and chemical stability of the water-based treatment agent, and still have better stability and durability under harsh conditions; by adding block copolymers, the hydrophobic microspheres and the matrix resin are solved. The compatibility problem between lipids and hydrophobic microspheres is avoided, and the adhesion conflict between hydrophobic microspheres and substrates is avoided; polydopamine microspheres loaded with hydrophobic substances are used, so that the prepared water-based treatment agent has good hydrophobic properties, which can significantly improve the water resistance of the treatment agent, reduce the possibility of surface moisture penetration and pollution, and help to extend the service life of the water-based treatment agent in a humid environment; the introduction of the cross-linking agent provides an additional cross-linking effect for the water-based treatment agent, significantly improves the structural strength and stability of the coating, and further extends the service life; the water-based treatment agent prepared by the preparation method of the water-based treatment agent of the present invention has excellent hydrophobicity, adhesion, flexibility, weather resistance and wear resistance, meets the application requirements with high requirements on coating performance, and is very suitable for long-term protection applications in humid or harsh environments.

[0013] In addition, the technical solution provided by the present invention may also have the following technical features:

[0014] In one technical solution of the present invention, the method for preparing polydopamine microspheres loaded with a hydrophobic substance comprises:

[0015] S301, preparation of alkaline buffer solution: dispersing the oil droplet template in a solvent, then dropping a surfactant emulsion, stirring evenly to obtain a first emulsion, then adding tris(hydroxymethyl)aminomethane to the first emulsion, and adding hydrochloric acid to adjust the pH to obtain an alkaline buffer solution;

[0016] S302, preparation of polydopamine microspheres: adding dopamine powder to an alkaline buffer solution, stirring evenly, and then sequentially performing a first separation treatment and a first washing treatment to obtain polydopamine microspheres;

[0017] S303, loading a hydrophobic substance onto the polydopamine microspheres: dispersing a hydrophobic oily small molecule substance in a solvent, adding the polydopamine microspheres, stirring evenly, and sequentially performing a second separation treatment, a second washing treatment, and a drying treatment to obtain polydopamine microspheres loaded with a hydrophobic substance.

[0018] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: the polydopamine microspheres have a large specific surface area, can load more hydrophobic oily small molecules, and can release the hydrophobic oily small molecules when the aqueous treatment agent is damaged to repair the hydrophobic properties of the aqueous treatment agent; the oily droplet template formed by the emulsion method can make the particle size of the polydopamine microspheres uniform, which is conducive to forming a stable dispersion system in the aqueous treatment agent; by loading the hydrophobic substance on the surface of the polydopamine microspheres, the microspheres have excellent hydrophobic properties, so that the prepared aqueous treatment agent is suitable for the application of various waterproof coatings.

[0019] In one technical solution of the present invention, the pH of the alkaline buffer solution is 8-9; and / or the concentration of the alkaline buffer solution is 2 mg / mL-3 mg / mL; and / or the first separation treatment is a centrifugal separation treatment; and / or the first washing treatment is repeated 2-3 times; and / or the second washing treatment is repeated 3-5 times; and / or the second separation treatment is a centrifugal separation treatment.

[0020] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: the pH value of the alkaline buffer solution is set within the above range, which can promote the oxidative polymerization reaction of dopamine and form a microsphere structure; the concentration of the buffer solution is within the above range, which helps to provide a sufficient alkaline environment in the solution to maintain the polymerization rate and stability of dopamine; centrifugal separation is used as the first separation treatment and the second separation treatment to ensure that the microspheres are effectively separated during the washing process and the hydrophobic substance loading process; the first washing treatment and the second washing treatment are repeated the above number of times, and the by-products and unreacted components in the dopamine polymerization process are effectively removed through multiple washings to ensure the purity of the microspheres.

[0021] In one technical solution of the present invention, the amount of nanoparticles used is 1wt.%-16wt.% of the base resin; and / or the amount of curing agent used is 30wt.%-50wt.% of the base resin; and / or the amount of block copolymer used is 8wt.%-20wt.% of the base resin; and / or the amount of polydopamine microspheres loaded with hydrophobic substances is 1wt.%-6wt.% of the base resin; and / or the amount of cross-linking agent used is 10wt.%-30wt.% of the base resin; and / or the amount of auxiliary agent used is 1.5wt.%-5wt.% of the base resin.

[0022] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: when the dosage of nanoparticles is within the above range, an appropriate amount of nanoparticles can enhance the mechanical strength and wear resistance of the coating, while avoiding the agglomeration problem caused by excessively high concentration; when the dosage of the curing agent is within the above range, it is ensured that the curing agent effectively acts during the crosslinking and curing process, and the strength of the water-based treatment agent is ensured while taking into account the flexibility; when the dosage of the block copolymer is within the above range, it can enhance the compatibility between the hydrophobic microspheres and the matrix resin, and can alleviate the adhesion contradiction; when the dosage of the polydopamine microspheres loaded with hydrophobic substances is controlled within the above range, the uniform distribution of the hydrophobic microspheres is ensured; when the dosage of the crosslinking agent is within the above range, it can provide a moderate crosslinking density for the coating, and further enhance the structural strength and chemical resistance of the water-based treatment agent; when the dosage of the auxiliary agent is within the above range, the rheological properties, defoaming properties and other properties of the water-based treatment agent can be improved, which is helpful to improve the smoothness of the construction operation and ensure the stable quality of the water-based treatment agent.

[0023] In one technical solution of the present invention, the nanoparticles include nano zinc oxide particles, nano cerium oxide particles and nano titanium oxide particles; and / or the curing agent includes water-based isocyanate; and / or the block copolymer includes a copolymer containing a fluorine structure or a copolymer containing a siloxane structure; and / or the cross-linking agent includes at least one of water-based isocyanate, water-based amino resin, epoxy resin, diethylaminopropylamine and polycarbodiimide; and / or the auxiliary agent includes at least one of a wetting agent, a leveling agent, a thickener, a defoaming agent and a photoinitiator.

[0024] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: the use of the above-mentioned types of nanoparticles can enhance its ability to resist ultraviolet light degradation and extend the service life of the water-based treatment agent; water-based isocyanate is used as a curing agent and a cross-linking agent, which can form a tightly cross-linked network structure with the base resin, thereby enhancing the chemical resistance of the coating; the introduction of a block copolymer containing siloxane or fluoride can, on the one hand, adhere well to the substrate, and on the other hand, have a small amount of hydrophobic groups, which can buffer the adhesion contradiction between the hydrophobic surface layer and the substrate; the cross-linking agent is selected from the above-mentioned types, which can form a high-density cross-linking network with the base resin, thereby enhancing the adhesion and flexibility of the water-based treatment agent; by selecting the above-mentioned types of additives, the water-based treatment agent can be evenly spread on the substrate to prevent the generation of bubbles, sagging or surface defects.

[0025] In one technical solution of the present invention, the frequency of the first ultrasonic treatment is 20kHz-40kHz; and / or the rotation speed of the first stirring treatment is 1200r / min-1800r / min; and / or the rotation speed of the second stirring treatment is 100r / min-400r / min.

[0026] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: the first ultrasonic treatment is carried out at the above frequency, and the nanoparticle agglomerates can be effectively broken up by ultrasonic vibration, so that the nanoparticles are more evenly dispersed in the solution; the rotation speed of the first stirring treatment is within a relatively high range, which can ensure that the base resin and the curing agent are evenly mixed in the water to form a stable emulsion; the second stirring treatment adopts a relatively low rotation speed, which helps to avoid the introduction of bubbles during the mixing process and reduce the re-aggregation of particles.

[0027] In a technical solution of the present invention, in S300, after the second stirring process, the following steps are further performed:

[0028] S310, performing a second ultrasonic treatment on the mixed solution after the second stirring treatment;

[0029] S320, adding the crosslinking agent emulsion to the mixed solution subjected to the second ultrasonic treatment, and stirring evenly.

[0030] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: performing a second ultrasonic treatment after the second stirring treatment helps to further refine the particles and improve the uniformity of dispersion; further adding a low-cost cross-linking agent emulsion after the second ultrasonic treatment helps to form a stable emulsion and prevent stratification.

[0031] In one technical solution of the present invention, the frequency of the second ultrasonic treatment is 40kHz-60kHz; and / or the amount of the crosslinking agent emulsion is 0.2wt.%-1wt.% of the mixed solution subjected to the second ultrasonic treatment.

[0032] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: using the above-mentioned frequency for the second ultrasonic treatment helps to further deagglomerate the remaining tiny particles in the mixed liquid and evenly distribute them in the matrix, effectively reducing the agglomeration phenomenon between the particles; using an appropriate amount of cross-linking agent to participate in the reaction avoids side reactions or environmental impacts that may be caused by excessive addition, and also helps to reduce production costs.

[0033] In one technical solution of the present invention, the auxiliary agent also includes: an adhesion promoter and / or an environmental stabilizer; the adhesion promoter includes at least one of 1,2-bis(trimethoxysilyl)ethane, hydroxyethyl methacrylate phosphate, and N,N-dimethyl-3-aminopropyltrimethoxysilane; the environmental stabilizer includes poly(4-hydroxy-2,2,6,6-tetramethyl-1-piperidinol) succinate.

[0034] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: in the process of preparing the water-based treatment agent, the adhesion promoter can significantly improve the adhesion between the water-based treatment agent and the coated surface, ensure the stability and durability of the water-based treatment agent during use, and reduce peeling and shedding phenomena; the environmental stabilizer can effectively enhance the coating's resistance to environmental influences, and by forming a stable network structure, improve the water-based treatment agent's resistance to temperature, humidity and ultraviolet rays, thereby extending the service life of the water-based treatment agent.

[0035] To achieve the second purpose of the present invention, the present invention provides an aqueous treatment agent, which is prepared by the preparation method of any one of the above technical solutions.

[0036] The aqueous treatment agent of the present invention can realize the control method of the aqueous treatment agent of any technical solution of the present invention. The aqueous treatment agent of the present invention has all the beneficial effects of the control method of the aqueous treatment agent of any technical solution of the present invention, which will not be repeated here.

[0037] After adopting the technical solution of the present invention, the following technical effects can be achieved:

[0038] 1. The aqueous treatment agent prepared by the preparation method of the aqueous treatment agent of the present invention has excellent hydrophobicity, adhesion, flexibility, weather resistance and abrasion resistance, meets the application requirements with high requirements on coating performance, and is very suitable for long-term protection applications in humid or harsh environments;

[0039] 2. The oily droplet template formed by the emulsion method can make the particle size of the prepared polydopamine microspheres loaded with hydrophobic substances uniform, which is conducive to forming a stable dispersion system in the aqueous treatment agent, making the aqueous treatment agent uniform, smooth in appearance and without obvious granularity;

[0040] 3. The water-based treatment agent of the present invention uses polyaspartic acid resin and modified hydroxypropyl acrylate as the base resin, which not only provides excellent adhesion but also enhances the flexibility of the coating, and is particularly suitable for coating applications on surfaces of different materials;

[0041] 4. By adding block copolymers, the compatibility problem between the hydrophobic microspheres and the matrix resin is solved, the adhesion conflict between the hydrophobic microspheres and the substrate is avoided, the water-based treatment agent is made more uniform, and the surface is ensured to be smooth and stable. DETAILED DESCRIPTION

[0042] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] In the related art, water-based treatment agents need to have both excellent hydrophobicity and high adhesion, but the two are often contradictory and difficult to balance. In view of this, the present invention provides a water-based treatment agent, which balances the hydrophobicity and adhesion of the water-based treatment agent by adding a block polymer, so that the water-based treatment agent has good hydrophobicity and high adhesion.

[0044] Specifically, an embodiment of the present invention provides a method for preparing an aqueous treatment agent, comprising:

[0045] S100, preparing a nanoparticle dispersion: adding nanoparticles and a dispersant into deionized water and performing a first ultrasonic treatment to obtain a nanoparticle dispersion;

[0046] S200, preparing a base resin emulsion: adding a base resin and a curing agent into deionized water for a first stirring treatment to obtain a base resin emulsion;

[0047] S300, preparing a water-based treatment agent: adding a base resin emulsion to a nanoparticle dispersion for a second stirring treatment, and sequentially adding a block copolymer, a hydrophobic microsphere, a crosslinking agent, and an auxiliary agent during the second stirring treatment to obtain a water-based treatment agent;

[0048] The matrix resin includes polyaspartic acid resin and modified hydroxypropyl acrylate; the hydrophobic microspheres are polydopamine microspheres loaded with hydrophobic substances.

[0049] Preferably, the water-based treatment agent of the present invention uses polyaspartic acid resin and modified hydroxypropyl acrylate as matrix resins, which not only provide excellent adhesion but also enhance the flexibility of the coating. The polyaspartic acid resin can form a denser cross-linked structure, giving the coating higher mechanical strength and wear resistance. The modified hydroxypropyl acrylate can further enhance the flexibility and adaptability of the water-based treatment agent, and is particularly suitable for coating applications on surfaces of different materials. The preferred mass ratio of the polyaspartic acid resin and the modified hydroxypropyl acrylate is (1-2): 1; the nanoparticles are ultrasonically treated together with the dispersant in deionized water. The dispersant and the ultrasonic treatment ensure uniform dispersion of the nanoparticles, so that the nanoparticles can improve the wear resistance, UV resistance and chemical stability of the water-based treatment agent, so that it can still be used under harsh conditions. The invention has better stability and durability, and the dispersant is preferably polyoxyethylene ether or acrylic copolymer; by adding block copolymer, the compatibility problem between hydrophobic microspheres and matrix resin is solved, and the adhesion conflict between hydrophobic microspheres and substrate is avoided, so that the water-based treatment agent can form a uniform film, ensuring the surface flatness and stability; the use of polydopamine microspheres loaded with hydrophobic substances can form a super-hydrophobic structure, making it difficult for water and dirt to adhere, so that the prepared water-based treatment agent has good hydrophobic properties, which can significantly improve the water resistance of the treatment agent, reduce the possibility of surface moisture penetration and pollution, and help to extend the service life of the water-based treatment agent in a humid environment; the introduction of the cross-linking agent provides an additional cross-linking effect for the water-based treatment agent, significantly improves the structural strength and stability of the coating, and further extends the service life.

[0050] Preferably, the aqueous treatment agent prepared by the preparation method of the aqueous treatment agent of the present invention has excellent hydrophobicity, adhesion, flexibility, weather resistance and abrasion resistance, meets the application requirements for higher coating performance, and is very suitable for long-term protection applications in humid or harsh environments.

[0051] Furthermore, in S300, after the second stirring process, the following steps are further performed:

[0052] S310, performing a second ultrasonic treatment on the mixed solution after the second stirring treatment;

[0053] S320, adding the crosslinking agent emulsion to the mixed solution subjected to the second ultrasonic treatment, and stirring evenly.

[0054] Preferably, the frequency of the second ultrasonic treatment is 40kHz-60kHz, and the time is 5min-10min, which helps to further refine the particles and improve the dispersion uniformity; the amount of the crosslinker emulsion is 0.2wt.%-1wt.% of the mixed solution after the second ultrasonic treatment, which helps to form a stable emulsion and prevent stratification.

[0055] Preferably, the preparation method of polydopamine microspheres loaded with hydrophobic substances comprises:

[0056] S301, preparation of alkaline buffer solution: dispersing the oil droplet template in a solvent, then dropping a surfactant emulsion, stirring evenly to obtain a first emulsion, then adding tris(hydroxymethyl)aminomethane to the first emulsion, and adding hydrochloric acid to adjust the pH to obtain an alkaline buffer solution;

[0057] S302, preparation of polydopamine microspheres: adding dopamine powder to an alkaline buffer solution, stirring evenly, and then sequentially performing a first separation treatment and a first washing treatment to obtain polydopamine microspheres;

[0058] S303, loading a hydrophobic substance onto the polydopamine microspheres: dispersing a hydrophobic oily small molecule substance in a solvent, adding the polydopamine microspheres, stirring evenly, and sequentially performing a second separation treatment, a second washing treatment, and a drying treatment to obtain polydopamine microspheres loaded with a hydrophobic substance.

[0059] Preferably, polydopamine is a biocompatible material polymerized from the natural amino acid dopamine, has low toxicity and is environmentally friendly, and polydopamine microspheres are used to load hydrophobic substances, so that the water-based treatment agent is more in line with environmental protection requirements; polydopamine microspheres are used as carriers to evenly disperse hydrophobic substances in the coating, which helps to construct a micro-nano rough structure and form a significant hydrophobic effect on the surface; and polydopamine microspheres have a large specific surface area and can load more hydrophobic oily small molecules, and can release hydrophobic oily small molecules when the water-based treatment agent is damaged to repair the hydrophobic properties of the water-based treatment agent.

[0060] Preferably, the oily droplet template formed by the emulsion method can make the particle size of the polydopamine microspheres uniform, which is conducive to forming a stable dispersion system in the aqueous treatment agent, making the aqueous treatment agent uniform, smooth in appearance and without obvious granularity. In addition, this method is relatively simple in process and is easy to produce a hydrophobic, highly adhesive and environmentally stable aqueous treatment agent, which is suitable for industrial applications and helps to reduce production costs and improve efficiency.

[0061] Preferably, the pH of the alkaline buffer solution is 8-9, so that dopamine molecules undergo polymerization reaction in an alkaline environment to form polydopamine microspheres. This moderate pH range can not only promote the oxidative polymerization reaction of dopamine to form a microsphere structure, but also avoid the instability caused by an overly alkaline environment, thereby improving the morphology and size uniformity of the microspheres.

[0062] Preferably, the concentration of the alkaline buffer solution is 2 mg / mL-3 mg / mL, which helps to provide a sufficient alkaline environment in the solution to maintain the polymerization speed and stability of dopamine. A moderate concentration can prevent the agglomeration problem caused by too fast polymerization, thereby obtaining uniformly dispersed and uniformly sized microspheres.

[0063] Furthermore, the first separation treatment is a centrifugal separation treatment, the first washing treatment is repeated 2-3 times, the second washing treatment is repeated 3-5 times, and the second separation treatment is a centrifugal separation treatment, which ensures that the microspheres are effectively separated during the washing process and the hydrophobic substance loading process, reduces the residual impurities and unreacted products, and improves the product purity. Repeated washing is beneficial to the loading uniformity and firmness of the hydrophobic substance. The clean microsphere surface can increase the binding efficiency of the hydrophobic substance, thereby improving the hydrophobic performance and stability of the microspheres finally obtained.

[0064] Preferably, the amount of nanoparticles is 1wt.%-16wt.% of the matrix resin. An appropriate amount of nanoparticles can enhance the mechanical strength and wear resistance of the coating, while avoiding the agglomeration problem caused by excessively high concentrations, making the surface of the water-based treatment agent smoother and more uniform; the amount of curing agent is 30wt.%-50wt.% of the matrix resin, which ensures that the curing agent effectively acts during the crosslinking and curing process, ensuring the strength of the water-based treatment agent while taking into account flexibility; the amount of block copolymer is 8wt.%-20wt.% of the matrix resin, which can not only enhance the compatibility between the hydrophobic microspheres and the matrix resin, but also alleviate the contradiction between the hydrophobicity and adhesion of the water-based treatment agent, ensuring that the water-based treatment agent can be on the matrix resin. The surface of the material is uniformly and stably film-formed; the dosage of polydopamine microspheres loaded with hydrophobic substances is 1wt.%-6wt.% of the base resin, which not only ensures the uniform distribution of the hydrophobic microspheres, but also avoids excessive influence on the flexibility of the coating; the dosage of the cross-linking agent is 10wt.%-30wt.% of the base resin, which can provide a moderate cross-linking density for the water-based treatment agent, thereby enhancing the structural strength and chemical resistance, improving the tolerance of the coating in high temperature, humid or corrosive environments, and extending its service life; the dosage of the auxiliary agent is 1.5wt.%-5wt.% of the base resin, which can improve the rheological properties, defoaming properties and other properties of the water-based treatment agent, help improve the smoothness of the construction operation, and ensure the stable quality of the water-based treatment agent.

[0065] Preferably, the nanoparticles include nano zinc oxide particles, nano cerium oxide particles and nano titanium oxide particles. Nano zinc oxide and nano titanium oxide have excellent ultraviolet absorption characteristics, which can effectively reduce light aging and extend the life of the coating. Nano cerium oxide helps to improve the antioxidant performance and enhance the corrosion resistance of the coating. The mass ratio of nano zinc oxide particles, nano cerium oxide particles and nano titanium oxide particles is (0.3-1): (0.05-0.5): (0.03-0.1); the curing agent includes water-based isocyanate. As a curing agent, water-based isocyanate can be cured at a lower temperature, improve the adhesion and chemical resistance of the coating, and make the coating more stable and firm; the block copolymer includes a copolymer containing a fluorine structure or a copolymer containing a siloxane structure. The block copolymer containing siloxane or fluoride is introduced. On the one hand, it has good adhesion to the substrate, and on the other hand, it has a small amount of hydrophobic groups, which can buffer the adhesion conflict between the hydrophobic surface layer and the substrate; the cross-linking agent includes water-based isocyanate, water-based amino resin, epoxy resin At least one of epoxy resin, diethylaminopropylamine and polycarbodiimide, these cross-linking agents help to form a stable three-dimensional network structure in the coating, so that the coating exhibits good mechanical properties and chemical stability after curing, wherein water-based isocyanate and water-based amino resin enhance adhesion and chemical resistance, epoxy resin increases hardness and toughness, diethylaminopropylamine improves heat resistance, and polycarbodiimide enhances moisture resistance and wear resistance of the coating; the auxiliary agent includes at least one of a wetting agent, a leveling agent, a thickener, a defoaming agent and a photoinitiator, the wetting agent and the leveling agent can optimize the construction performance of the coating, reduce surface defects such as brush marks and sagging, and make the coating more flat and smooth, the thickener adjusts the viscosity of the coating, improves the fluidity and construction performance of the coating, and adapts it to different construction processes, the defoaming agent can eliminate bubbles in the coating, improve the transparency and aesthetics of the coating, and avoid the strength reduction caused by bubbles, the photoinitiator can quickly initiate curing under ultraviolet light, facilitates rapid curing applications, and is suitable for efficient and rapid construction needs.

[0066] Furthermore, the additives also include: adhesion promoters and / or environmental stabilizers. The adhesion promoters can significantly improve the adhesion between the water-based treatment agent and the coated surface, ensure the stability and durability of the water-based treatment agent during use, and reduce peeling and shedding phenomena; the environmental stabilizers can effectively enhance the coating's resistance to environmental influences, and by forming a stable network structure, improve the water-based treatment agent's resistance to temperature, humidity and ultraviolet rays, thereby extending the service life of the water-based treatment agent.

[0067] Preferably, the adhesion promoter includes at least one of 1,2-bis(trimethoxysilyl)ethane, hydroxyethyl methacrylate phosphate, and N,N-dimethyl-3-aminopropyltrimethoxysilane, which can form a strong bond with the surface of the substrate through chemical reaction or physical adsorption, and can significantly improve the adhesion between the water-based treatment agent and the coated surface, ensuring the stability and durability of the water-based treatment agent during use.

[0068] Preferably, the environmental stabilizer includes poly(4-hydroxy-2,2,6,6-tetramethyl-1-piperidinylethanol) succinate, which forms a stable network structure to improve the resistance of the aqueous treatment agent to temperature, humidity and ultraviolet rays, thereby extending the service life of the aqueous treatment agent.

[0069] Preferably, the frequency of the first ultrasonic treatment is 20kHz-40kHz. High-frequency ultrasonic vibration can effectively break up nanoparticle agglomerates and make the nanoparticles more evenly dispersed in the solution, which helps to improve the uniform distribution of nanoparticles in the aqueous treatment agent and enhance the wear resistance, UV resistance and corrosion resistance of the treatment agent; the rotation speed of the first stirring treatment is 1200r / min-1800r / min, which can ensure that the base resin and the curing agent are evenly mixed in water to form a stable emulsion. The stirring treatment at a higher speed not only improves the stability of the emulsion, but also promotes the uniform film-forming effect of the coating, ensuring the smoothness and adhesion of the final coating; the rotation speed of the second stirring treatment is 100r / min-400r / min, which helps to avoid the introduction of bubbles during the mixing process and reduce the re-aggregation of particles. The low-speed stirring ensures that components such as block copolymers, hydrophobic microspheres and additives are evenly dispersed in the treatment agent, so that the aqueous treatment agent has better surface smoothness and structural stability.

[0070] Embodiment 1

[0071] This embodiment provides an aqueous treatment agent, and the preparation method thereof adopts the following steps:

[0072] S100, adding nano zinc oxide particles, nano cerium oxide particles and nano titanium oxide particles in a mass ratio of 0.3:0.05:0.03 together with polyoxyethylene ether into deionized water, and performing a first ultrasonic treatment at a frequency of 20 kHz to obtain a nano particle dispersion;

[0073] S200, adding polyaspartic acid resin and modified hydroxypropyl acrylate in a mass ratio of 1:1 and aqueous isocyanate into deionized water, and performing a first stirring treatment at a rotation speed of 1200 r / min to obtain a base resin emulsion;

[0074] S300, adding the matrix resin emulsion to the nanoparticle dispersion, performing a second stirring treatment at a rotation speed of 100 r / min, and sequentially adding a fluorine-containing block copolymer, polydopamine microspheres loaded with a hydrophobic substance, an aqueous isocyanate, and an auxiliary agent during the second stirring treatment to obtain an aqueous treatment agent;

[0075] Among them, the amount of polyoxyethylene ether in S100 is 1wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, the amount of aqueous isocyanate in S200 is 30wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, and in S300, the amount of fluorine-containing block copolymer is 8wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, the amount of polydopamine microspheres loaded with hydrophobic substances is 1wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, the amount of aqueous isocyanate is 10wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, and the amount of auxiliary agent is 1.5wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, and the auxiliary agent is a defoaming agent;

[0076] The preparation method of polydopamine microspheres loaded with hydrophobic substances comprises:

[0077] S301, dispersing the oily droplet template in a solvent, then dropping a surfactant emulsion, stirring evenly to obtain a first emulsion, then adding tris(hydroxymethyl)aminomethane to the first emulsion, adding hydrochloric acid to adjust the pH to 8, and obtaining an alkaline buffer solution with a concentration of 2 mg / mL;

[0078] S302, adding dopamine powder to the alkaline buffer solution, stirring evenly, performing centrifugal separation, and then performing a first washing process, and repeating the first washing process twice to obtain polydopamine microspheres;

[0079] S303, loading hydrophobic substances on polydopamine microspheres: disperse hydrophobic oily small molecule substances in a solvent, add polydopamine microspheres, stir evenly, perform centrifugal separation treatment, and then perform a second washing treatment and drying treatment. Repeat the second washing treatment 3 times to obtain polydopamine microspheres loaded with hydrophobic substances.

[0080] Embodiment 2

[0081] This embodiment provides an aqueous treatment agent, and the preparation method thereof adopts the following steps:

[0082] S100, adding nano zinc oxide particles, nano cerium oxide particles and nano titanium oxide particles together with an acrylic copolymer in a mass ratio of 1:0.5:0.1 into deionized water, and performing a first ultrasonic treatment at a frequency of 40 kHz to obtain a nano particle dispersion;

[0083] S200, adding polyaspartic acid resin and modified hydroxypropyl acrylate in a mass ratio of 2:1 and aqueous isocyanate into deionized water, and performing a first stirring treatment at a rotation speed of 1800 r / min to obtain a base resin emulsion;

[0084] S300, adding the matrix resin emulsion to the nanoparticle dispersion, performing a second stirring treatment at a speed of 400 r / min, sequentially adding a block copolymer containing a siloxane structure, polydopamine microspheres loaded with a hydrophobic substance, an epoxy resin, and an auxiliary agent during the second stirring treatment, performing an ultrasonic treatment at 40 kHz after the second stirring treatment, adding 1 wt.% of a cross-linking agent to the mixed solution subjected to the second ultrasonic treatment after the ultrasonic treatment, stirring evenly, and obtaining an aqueous treatment agent;

[0085] Among them, the amount of polyoxyethylene ether in S100 is 16wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, the amount of aqueous isocyanate in S200 is 50wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, and in S300, the amount of block copolymer containing siloxane structure is 20wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, the amount of polydopamine microspheres loaded with hydrophobic substance is 6wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, the amount of epoxy resin is 30wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, and the amount of auxiliary agent is 5wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, and the auxiliary agent is a defoamer and a photoinitiator;

[0086] The preparation method of polydopamine microspheres loaded with hydrophobic substances comprises:

[0087] S301, dispersing the oily droplet template in a solvent, then dropping a surfactant emulsion, stirring evenly to obtain a first emulsion, then adding tris(hydroxymethyl)aminomethane to the first emulsion, adding hydrochloric acid to adjust the pH to 9, and obtaining an alkaline buffer solution with a concentration of 3 mg / mL;

[0088] S302, adding dopamine powder to the alkaline buffer solution, stirring evenly, performing centrifugal separation, and then performing a first washing process, and repeating the first washing process 3 times to obtain polydopamine microspheres;

[0089] S303, loading hydrophobic substances on polydopamine microspheres: disperse hydrophobic oily small molecule substances in a solvent, add polydopamine microspheres, stir evenly, perform centrifugal separation treatment, and then perform a second washing treatment and drying treatment. Repeat the second washing treatment 5 times to obtain polydopamine microspheres loaded with hydrophobic substances.

[0090] Embodiment 3

[0091] This embodiment provides an aqueous treatment agent, and the preparation method thereof adopts the following steps:

[0092] S100, adding nano zinc oxide particles, nano cerium oxide particles and nano titanium oxide particles in a mass ratio of 0.8:0.2:0.07 together with an acrylic copolymer into deionized water, and performing a first ultrasonic treatment at a frequency of 35 kHz to obtain a nano particle dispersion;

[0093] S200, adding polyaspartic acid resin and modified hydroxypropyl acrylate in a mass ratio of 2:1 and aqueous isocyanate into deionized water, and performing a first stirring treatment at a rotation speed of 1500 r / min to obtain a base resin emulsion;

[0094] S300, adding the matrix resin emulsion to the nanoparticle dispersion, performing a second stirring treatment at a rotation speed of 200 r / min, sequentially adding a block copolymer containing a siloxane structure, polydopamine microspheres loaded with a hydrophobic substance, a water-based amino resin, and an auxiliary agent during the second stirring treatment, performing an ultrasonic treatment at 60 kHz after the second stirring treatment, adding 0.2 wt.% of a cross-linking agent to the mixed solution subjected to the second ultrasonic treatment after the ultrasonic treatment, stirring evenly, and obtaining an aqueous treatment agent;

[0095] Among them, the amount of polyoxyethylene ether in S100 is 10wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, the amount of aqueous isocyanate in S200 is 40wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, and in S300, the amount of block copolymer containing siloxane structure is 12wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, the amount of polydopamine microspheres loaded with hydrophobic substance is 3wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, the amount of aqueous amino resin is 20wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate, and the amount of auxiliary agent is 3wt.% of the total mass of polyaspartic acid resin and modified hydroxypropyl acrylate. The auxiliary agents are defoaming agent, photoinitiator, and adhesion promoter;

[0096] The preparation method of polydopamine microspheres loaded with hydrophobic substances comprises:

[0097] S301, dispersing the oily droplet template in a solvent, then dropping a surfactant emulsion, stirring evenly to obtain a first emulsion, then adding tris(hydroxymethyl)aminomethane to the first emulsion, adding hydrochloric acid to adjust the pH to 9, and obtaining an alkaline buffer solution with a concentration of 3 mg / mL;

[0098] S302, adding dopamine powder to the alkaline buffer solution, stirring evenly, performing centrifugal separation, and then performing a first washing process, and repeating the first washing process 3 times to obtain polydopamine microspheres;

[0099] S303, loading hydrophobic substances on polydopamine microspheres: disperse hydrophobic oily small molecule substances in a solvent, add polydopamine microspheres, stir evenly, perform centrifugal separation treatment, and then perform a second washing treatment and drying treatment. Repeat the second washing treatment 5 times to obtain polydopamine microspheres loaded with hydrophobic substances.

[0100] Performance Testing

[0101] The aqueous treatment agents of Examples 1-3 were applied to leather surfaces to form coatings, and the samples were tested. The test results are shown in Table 1.

[0102] Adhesion test: The samples were tested using the cross-cut method according to ASTM D3359;

[0103] Water resistance test: immerse the sample in water for 24 hours and observe the changes in the sample;

[0104] Wear resistance test: Use an abrasion tester to rotate the grinding wheel on the sample surface 1000 times and record the weight change;

[0105] Hydrophobicity test: The water contact angle on the sample surface is measured by a contact angle meter;

[0106] Weathering test: After 500 hours of UV irradiation, the changes in the surface are evaluated.

[0107] Table 1

[0108]

[0109] It can be seen from Table 1 that the aqueous treatment agent prepared by the preparation method of the aqueous treatment agent of the present invention has good adhesion, hydrophobicity, water resistance, wear resistance and weather resistance, especially the aqueous treatment agents in Example 2 and Example 3. This may be because they are ultrasonically treated again after the second stirring treatment and the crosslinking agent emulsion is added dropwise, so that the particles in the aqueous treatment agent are further refined and more stable.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing an aqueous treatment agent, characterized in that: include: S100, preparing a nanoparticle dispersion: adding nanoparticles and a dispersant into deionized water and performing a first ultrasonic treatment to obtain a nanoparticle dispersion; S200, preparing a base resin emulsion: adding a base resin and a curing agent into deionized water for a first stirring treatment to obtain the base resin emulsion; S300, preparing an aqueous treatment agent: adding the base resin emulsion to the nanoparticle dispersion for a second stirring treatment, and sequentially adding a block copolymer, hydrophobic microspheres, a crosslinking agent, and an auxiliary agent during the second stirring treatment to obtain the aqueous treatment agent; Wherein, the base resin includes polyaspartic acid resin and modified hydroxypropyl acrylate; The hydrophobic microspheres are polydopamine microspheres loaded with hydrophobic substances.

2. The preparation method according to claim 1, characterized in that: The preparation method of the polydopamine microspheres loaded with a hydrophobic substance comprises: S301, preparation of an alkaline buffer solution: dispersing an oily droplet template in a solvent, then dropping a surfactant emulsion, stirring evenly to obtain a first emulsion, then adding tris(hydroxymethyl)aminomethane to the first emulsion, and adding hydrochloric acid to adjust the pH to obtain the alkaline buffer solution; S302, preparation of polydopamine microspheres: adding dopamine powder to the alkaline buffer solution, stirring evenly, and then sequentially performing a first separation treatment and a first washing treatment to obtain polydopamine microspheres; S303, loading a hydrophobic substance onto the polydopamine microspheres: dispersing a hydrophobic oily small molecule substance in a solvent, adding the polydopamine microspheres, stirring evenly, and sequentially performing a second separation treatment, a second washing treatment, and a drying treatment to obtain the polydopamine microspheres loaded with the hydrophobic substance.

3. The preparation method according to claim 2, characterized in that: The pH of the alkaline buffer solution is 8-9; and / or The concentration of the alkaline buffer solution is 2 mg / mL-3 mg / mL; and / or The first separation process is a centrifugal separation process; and / or The first washing treatment is repeated 2 to 3 times; and / or The second washing treatment is repeated 3 to 5 times; and / or The second separation process is a centrifugal separation process.

4. The preparation method according to claim 1, characterized in that: The amount of the nanoparticles is 1wt.%-16wt.% of the base resin; and / or The amount of the curing agent is 30wt.%-50wt.% of the base resin; and / or The block copolymer is used in an amount of 8wt.%-20wt.% of the base resin; and / or The amount of the polydopamine microspheres loaded with hydrophobic substances is 1wt.%-6wt.% of the base resin; and / or The amount of the cross-linking agent is 10wt.%-30wt.% of the base resin; and / or The amount of the auxiliary agent used is 1.5wt.%-5wt.% of the base resin.

5. The preparation method according to claim 4, characterized in that: The nanoparticles include nano zinc oxide particles, nano cerium oxide particles and nano titanium oxide particles; and / or The curing agent comprises water-based isocyanate; and / or The block copolymer includes a copolymer containing a fluorine structure or a copolymer containing a siloxane structure; and / or The cross-linking agent comprises at least one of water-based isocyanate, water-based amino resin, epoxy resin, diethylaminopropylamine and polycarbodiimide; and / or The auxiliary agent includes at least one of a wetting agent, a leveling agent, a thickener, a defoaming agent and a photoinitiator.

6. The preparation method according to claim 1, characterized in that: The frequency of the first ultrasonic treatment is 20kHz-40kHz; and / or The rotation speed of the first stirring treatment is 1200r / min-1800r / min; and / or The rotation speed of the second stirring treatment is 100 r / min-400 r / min.

7. The preparation method according to claim 1, characterized in that: In the S300, after the second stirring process, the following further comprises: S310, performing a second ultrasonic treatment on the mixed solution after the second stirring treatment; S320, adding the crosslinking agent emulsion to the mixed solution subjected to the second ultrasonic treatment, and stirring the mixture evenly.

8. The preparation method according to claim 7, characterized in that: The frequency of the second ultrasonic treatment is 40kHz-60kHz; and / or The amount of the cross-linking agent emulsion used is 0.2wt.%-1wt.% of the mixed solution subjected to the second ultrasonic treatment.

9. The preparation method according to claim 5, characterized in that: The auxiliary agent also includes: an adhesion promoter and / or an environmental stabilizer; The adhesion promoter includes at least one of 1,2-bis(trimethoxysilyl)ethane, hydroxyethyl methacrylate phosphate, and N,N-dimethyl-3-aminopropyltrimethoxysilane; The environmental stabilizer includes poly(4-hydroxy-2,2,6,6-tetramethyl-1-piperidinylethanol) succinate.

10. An aqueous treatment agent, characterized in that The aqueous treatment agent is prepared by the method for preparing an aqueous treatment agent according to any one of claims 1 to 9.

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