An environmentally friendly water-based paint and its preparation method

Abstract

This invention belongs to the field of water-based paint preparation technology, and particularly relates to an environmentally friendly water-based paint and its preparation method. The water-based paint is obtained by mixing and stirring raw materials including water-based acrylic resin emulsion, self-healing capsules, inorganic fillers, pigments, defoamers, and leveling agents. Polyether-modified aminopolysiloxane is used as the shell material; a natural drying oil-based self-healing agent is used as the core material to prepare the self-healing capsule. When the paint film cracks or is subjected to external impact, the capsule ruptures and releases the core material, enabling precise positioning and repair.

Description

Technical Field

[0001] This invention belongs to the field of water-based paint preparation technology, specifically relating to an environmentally friendly water-based paint and its preparation method. Background Technology

[0002] Paint, as a type of coating, refers to a general term for liquid or solid materials that are applied to the surface of an object to form a solid film with protective, decorative, or special properties. Traditional paints are widely used due to their excellent performance and ease of application. However, because they use organic solvents as dispersion media and diluents, they release large amounts of volatile organic compounds during production, application, and drying, leading to serious environmental, health, and safety problems. Water-based paints emerged to address this issue. Water-based paints use water as the main dispersion media and diluent, but they have shortcomings in properties such as adhesion and hardness.

[0003] Chinese Patent CN119463601B discloses a modified inorganic particle-doped water-based paint and its preparation method. The paint uses raw materials including water-based acrylic resin, modified inorganic particles, polyvinyl alcohol, defoamer, and dispersant, which are mixed and stirred. It uses polyimide particles instead of nano-titanium dioxide as the flame-retardant component, and enhances the flame retardancy of the polyimide by subjecting both the polyimide particles and nano-titanium dioxide particles to high-temperature treatment; it also generates carbon quantum dots and graphene quantum dots, increasing the antibacterial durability of the water-based paint. Chinese Patent CN118772742B discloses a water-based anti-rust paint for AGV forklifts and its preparation method. The paint is composed of a mixture of components A, B, and C. Component A includes water-based epoxy resin, defoamer, leveling agent, wetting agent, dispersant, wear-resistant filler, rust inhibitor, anti-settling agent, and deionized water. Component B includes a curing agent and water. Component C contains zinc powder. By combining an organosilicon polyether-linked modified epoxy resin with a low molecular weight, low epoxy equivalent epoxy resin, the toughness and low-temperature resistance of the epoxy resin paint film can be effectively improved. The use of spherical fillers with epoxy-containing silane coupling agents and carboxybenzotriazole surface-modified fillers can compensate for the loss of wear resistance caused by the aforementioned epoxy resin, achieving a balance between paint film toughness and hardness, and low-temperature performance and wear resistance. However, paint will inevitably develop some micro-cracks during long-term use, and these cracks are difficult to detect in their early stages. The continuous expansion of these cracks will directly affect the service life of the material. Therefore, how to effectively extend the service life of paint has become a key research focus. Summary of the Invention

[0004] To address at least one of the above problems, the present invention provides an environmentally friendly method for preparing a water-based paint, comprising the following steps: S100. Self-healing capsules are prepared using polyether-modified amino polysiloxane and drying oil self-healing agents as raw materials. S200: Inorganic fillers are prepared using natural resins containing carboxyl groups and inorganic carbonates as raw materials. S300 is a water-based paint obtained by mixing and stirring water-based acrylic resin emulsion, self-healing capsules, inorganic fillers, pigments, defoamers, and leveling agents.

[0005] Furthermore, the preparation method of polyether-modified aminopolysiloxane is as follows: A1. Under an inert atmosphere, octamethylcyclotetrasiloxane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and 1,1,3,3-tetramethyldisiloxane are added to a reactor. The temperature is raised to 50-55℃, and the mixture is stirred for 10-20 min. The temperature is then raised to 100-105℃ and tetramethylammonium hydroxide is added. The reaction is carried out for 4-6 h. After the reaction is completed, the temperature is raised to 140-150℃ and the reaction is continued for 15-25 min. After vacuum treatment, hydrogen-containing amino silicone oil is obtained. A2. Add hydrogen-containing amino silicone oil, polyethylene glycol diacrylate and isopropanol to the reactor, raise the temperature to 50-55℃, mix and stir for 10-20 min, then add chloroplatinic acid-isopropanol solution and react for 20-40 min. Obtain polyether modified amino polysiloxane by vacuum distillation.

[0006] Furthermore, step S100 specifically includes: S110. A uniform oil phase is obtained by mixing a dry oil self-healing agent with a polyether-modified amino polysiloxane. S120. Add the oil phase to deionized water containing emulsifier, and shear at high speed for 15-25 min to form an oil-in-water emulsion. Add a crosslinking agent to the emulsion, raise the temperature to 45-55℃, reduce the stirring rate and stir for 2-4 h. After the reaction is completed, centrifuge, wash and dry to obtain the self-healing capsule.

[0007] Furthermore, the dry oil self-healing agent is one or a mixture of several of linseed oil, tung oil, tung oil, perilla oil, and hemp seed oil.

[0008] Furthermore, step S200 specifically includes: S210. Add calcium carbonate and dispersant to deionized water and stir at high speed for 20-40 minutes to obtain a calcium carbonate suspension. S220. Heat rosin until it melts, add triethanolamine and stir until homogeneous to obtain a mixture. Add the mixture dropwise to a calcium carbonate suspension, control the reaction temperature at 60-80℃, and stir for 1-2 hours. After the reaction is complete, filter, wash and dry to obtain rosin-modified calcium carbonate, which is the inorganic filler.

[0009] Furthermore, the preparation method of the waterborne acrylic resin emulsion is as follows: B1. Add butyl acrylate, styrene, hydroxyethyl acrylate and (meth)acrylic acid to the reactor, mix them evenly at room temperature, and then add them to a solution composed of water, disodium alkyl polyoxyethylene ether succinate monosulfonate and sodium 3-allyloxy-2-hydroxypropanesulfonate. Stir and emulsify to obtain a pre-emulsified monomer. B2. Add water, disodium alkyl polyoxyethylene ether succinate monoester sulfonate, sodium 3-allyloxy-2-hydroxypropanesulfonate, and ammonium persulfate to the reactor, heat to 70-75°C, add the pre-emulsified monomer, keep the reaction at this temperature for 20-40 minutes, then add the ammonium persulfate solution, keep the reaction at this temperature for 2-4 hours after the addition is complete, cool to room temperature, adjust the pH, and filter to obtain the aqueous acrylic resin emulsion.

[0010] Further, step S300 specifically includes: adding an aqueous acrylic resin emulsion to a reactor, adding deionized water while stirring, controlling the rotation speed at 300-400 r / min, stirring for 10-20 min, then adding inorganic fillers, increasing the rotation speed to 600-800 r / min, continuing to stir for 30-40 min, then adding self-healing capsules, reducing the rotation speed to 300-400 r / min, continuing to stir for 20-30 min, then sequentially adding pigments, fillers, defoamers, and leveling agents, maintaining the rotation speed at 300-400 r / min, stirring for 15-25 min, and then adjusting the paint to a suitable viscosity to obtain the aqueous paint.

[0011] An environmentally friendly water-based paint is prepared using the environmentally friendly water-based paint preparation method described in any of the above technical solutions.

[0012] The present invention has the following beneficial effects: In the preparation of self-healing capsules, hydrogen-containing amino silicone oil and polyethylene glycol diacrylate are used as raw materials, and chloroplatinic acid is used as a catalyst to prepare polyether-modified amino polysiloxane as the shell material; natural drying oil self-healing agents are used as the core material to prepare self-healing capsules. When the paint film cracks or is subjected to external impact, the capsule ruptures and releases the core material to achieve precise positioning and repair.

[0013] In the preparation of inorganic fillers, rosin is used to modify calcium carbonate. The rosin molecular chains are adsorbed on the surface of calcium carbonate through electrostatic interaction. After modification, the rosin molecular chains on the surface of calcium carbonate form steric hindrance, which hinders the aggregation between particles and improves its dispersibility in paint.

[0014] Using butyl acrylate, styrene, hydroxyethyl acrylate, and (meth)acrylic acid as raw materials, an aqueous acrylic resin emulsion containing hydroxyl groups is obtained after emulsification and polymerization. Its molecular chain contains polar groups such as carboxyl and hydroxyl groups, which can form hydrogen bonds with the polar groups on the surface of rosin-modified calcium carbonate inorganic filler and self-healing capsule, thereby enhancing its interfacial compatibility with the resin matrix and aiding in dispersion. Detailed Implementation

[0015] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0016] Traditional paints have long dominated the market due to their superior performance, but the volatile organic compounds they contain pose certain hazards to the environment and human health. Therefore, environmentally friendly water-based paints, which use water as a diluent, are gradually gaining attention. Although water-based paints are constantly evolving, improvements are still needed in areas such as hardness, abrasion resistance, and self-healing capabilities. Therefore, this invention provides a method for preparing an environmentally friendly water-based paint, comprising the following steps: S100. Self-healing capsules are prepared using polyether-modified amino polysiloxane and drying oil self-healing agents as raw materials. S200: Inorganic fillers are prepared using natural resins containing carboxyl groups and inorganic carbonates as raw materials. S300 is a water-based paint obtained by mixing and stirring water-based acrylic resin emulsion, self-healing capsules, inorganic fillers, pigments, defoamers, and leveling agents.

[0017] The preparation method of polyether-modified amino polysiloxane is as follows: A1. Under an inert atmosphere, octamethylcyclotetrasiloxane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, and 1,1,3,3-tetramethyldisiloxane are added to a reactor. The temperature is raised to 50-55℃, and the mixture is stirred for 10-20 minutes. The temperature is then raised to 100-105℃, and tetramethylammonium hydroxide is added. The reaction is carried out for 4-6 hours. After the reaction is completed, the temperature is raised to 140-150℃, and the reaction is continued for 15-25 minutes. After vacuum treatment, hydrogen-containing amino silicone oil is obtained. The mass ratio of octamethylcyclotetrasiloxane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, 1,1,3,3-tetramethyldisiloxane, and tetramethylammonium hydroxide is 70-90:5-15:6-10:0.05-0.15. A2. Add hydrogen-containing amino silicone oil, polyethylene glycol diacrylate, and isopropanol to a reactor, raise the temperature to 50-55℃, mix and stir for 10-20 min, then add 2% chloroplatinic acid-isopropanol solution and react for 20-40 min. Obtain polyether-modified amino polysiloxane by vacuum distillation; wherein the mass ratio of hydrogen-containing amino silicone oil, polyethylene glycol diacrylate, isopropanol, and chloroplatinic acid-isopropanol solution is 50-70:10-30:20-40:0.1-0.5.

[0018] In the above steps, polysiloxane is a polymer compound with silicon-oxygen bonds as the main chain and silicon atoms linked to organic groups. It has excellent resistance to high and low temperatures, radiation, and weathering. When mixed with film-forming substances in paint, it can improve the flexibility of the coating and reduce coating cracking caused by thermal expansion and contraction of the substrate. However, it has low surface energy and is prone to agglomeration and sedimentation in polar water-based paint systems due to insufficient compatibility, resulting in uneven dispersion. Therefore, in this invention, hydrogen-containing amino silicone oil and polyethylene glycol diacrylate are used as raw materials, and chloroplatinic acid is used as a catalyst to prepare polyether-modified amino polysiloxane. Polyether groups are introduced into the side chains of the polysiloxane structure to improve its hydrophilicity and enhance its binding force with water-based acrylic resin emulsions and other substances.

[0019] Specifically, step S100 includes: S110. A uniform oil phase is obtained by mixing a drying oil self-healing agent with a polyether-modified amino polysiloxane; wherein the mass ratio of the drying oil self-healing agent to the polyether-modified amino polysiloxane is 3-5:1. S120. Add the oil phase to deionized water containing emulsifier, and shear at high speed for 15-25 min to form an oil-in-water emulsion. Add a crosslinking agent to the emulsion, raise the temperature to 45-55℃, reduce the stirring rate and stir for 2-4 h. After the reaction is completed, centrifuge, wash and dry to obtain the self-healing capsule. The mass ratio of oil phase, emulsifier, deionized water and crosslinking agent is 10:0.5-1.5:30-50:0.05-0.15.

[0020] In the above steps, during long-term use, the paint will inevitably develop microcracks due to wear and aging. These microcracks are difficult to detect in time, and their continuous expansion will directly affect the material's service life. Therefore, this invention incorporates a self-healing agent during the preparation process to endow it with a certain self-repair capability. Under environmentally friendly conditions, this invention uses renewable natural plant oil resources as the self-healing agent. However, if drying oil-based self-healing agents are directly added as one of the raw materials during paint preparation, premature oxidation may occur due to trace amounts of oxygen in the system, leading to paint layering or even gelation. Furthermore, without any constraints during repair, the self-healing agent may flow too quickly, exceeding the crack area and causing waste. Therefore, this invention uses polyether-modified aminopolysiloxane as the shell material and drying oil self-healing agent as the core material to prepare a self-healing capsule. After being encapsulated, the shell material isolates the self-healing agent from external oxygen, moisture, and other active components, preventing premature oxidation. Furthermore, when the self-healing agent is encapsulated within the shell, the capsule only ruptures to release the core material when the paint film cracks or is subjected to external impact, achieving precise positioning and repair. Additionally, the shell material is prepared using polyether-modified aminopolysiloxane. Compared to preparation using polysiloxane, this allows the self-healing capsules to be stably dispersed in an aqueous medium, reducing defects such as pinholes and shrinkage caused by uneven distribution. Simultaneously, the flexible structure of the polyether segments reduces interfacial stress between the shell and core material, making the self-healing capsules more stable during storage and transportation.

[0021] The drying oil self-healing agent is one or a mixture of several of linseed oil, tung oil, tung oil, perilla oil, and hemp seed oil. Preferably, the drying oil self-healing agent is a mixture of tung oil and linseed oil in a mass ratio of 2-5:1.

[0022] In the above steps, the tung oil contains tung oil triglyceride, which is easily hydrolyzed into tung oil acid. Tung oil acid contains multiple conjugated double bonds and has a strong polymerization ability. The polymer formed after polymerization with oxygen can repair the matrix, but the cured film is brittle and prone to secondary cracking due to stress shrinkage. Linseed oil contains a large amount of unsaturated fatty acids, among which carbon-carbon double bonds are easily oxidized. The substances formed after oxidation form a new protective film that can repair damaged areas. Although it has a moderate curing speed and good flexibility, its initial repair efficiency is low. Therefore, this invention uses a mixture of tung oil and linseed oil as a self-healing agent. The rapid cross-linking of tung oil fills the initially formed cracks, while the slow polymerization of linseed oil relieves internal stress through molecular chain entanglement, making the repair layer less brittle.

[0023] Specifically, step S200 includes: S210. Add calcium carbonate and dispersant to deionized water and stir at high speed for 20-40 minutes to obtain a calcium carbonate suspension; wherein the mass ratio of deionized water, calcium carbonate and dispersant is 10-18:10:0.05-0.12. S220. Heat rosin until it melts, add triethanolamine and stir until homogeneous to obtain a mixture. Add the mixture dropwise to a calcium carbonate suspension, control the reaction temperature at 60-80℃, and stir for 1-2 hours. After the reaction is complete, filter, wash and dry to obtain rosin-modified calcium carbonate, which is the inorganic filler. The mass ratio of rosin, triethanolamine and calcium carbonate suspension is 5-8:0.2-0.6:8-11.

[0024] In the above steps, calcium carbonate is used as an inorganic filler, which is inexpensive, widely available, and harmless to the human body. In paint applications, it can form a skeletal support in the paint film, improving hardness and wear resistance. However, it is hydrophilic and oleophobic, with a relatively large surface energy, making it difficult to disperse evenly in paint. Therefore, rosin is used to modify its surface. Rosin molecular chains are adsorbed onto the calcium carbonate surface through electrostatic interaction. After modification, the rosin molecular chains on the calcium carbonate surface form steric hindrance, preventing particle aggregation and improving its dispersibility in paint. At the same time, it enhances its compatibility with water-based resins, thereby improving the stability and film performance of water-based paints.

[0025] The preparation method of the waterborne acrylic resin emulsion is as follows: B1. Add butyl acrylate, styrene, hydroxyethyl acrylate, and (meth)acrylic acid to a reactor, mix thoroughly at room temperature, and then add to a solution composed of water, disodium alkyl polyoxyethylene ether succinate monosulfonate, and sodium 3-allyloxy-2-hydroxypropanesulfonate. Stir and emulsify to obtain a pre-emulsified monomer; wherein the mass ratio of butyl acrylate, styrene, hydroxyethyl acrylate, (meth)acrylic acid, water, disodium alkyl polyoxyethylene ether succinate monosulfonate, and sodium 3-allyloxy-2-hydroxypropanesulfonate is 50-70:20-40:2-5:1-5:100-150:1-3:1-2. B2. Add water, disodium alkyl polyoxyethylene ether succinate monosulfonate, sodium 3-allyloxy-2-hydroxypropanesulfonate, and ammonium persulfate to a reactor, heat to 70-75℃, add pre-emulsified monomer, maintain the temperature for 20-40 min, then add 10% ammonium persulfate solution, maintain the temperature for 2-4 h after the addition, cool to room temperature, adjust the pH, and filter to obtain the aqueous acrylic resin emulsion; wherein the mass ratio of water, disodium alkyl polyoxyethylene ether succinate monosulfonate, sodium 3-allyloxy-2-hydroxypropanesulfonate, ammonium persulfate, pre-emulsified monomer, and ammonium persulfate solution is 80-120:0.5-1.2:0.3-0.8:0.15-0.35:150-180:1.8-3.2.

[0026] In the above steps, butyl acrylate, styrene, hydroxyethyl acrylate, and (meth)acrylic acid are used as raw materials. After adding a composite emulsifier, the mixture is stirred and emulsified to obtain a pre-emulsified monomer, which is then subjected to a polymerization reaction to obtain a waterborne acrylic resin emulsion containing hydroxyl groups.

[0027] Specifically, step S300 includes: adding an aqueous acrylic resin emulsion to the reactor, adding deionized water while stirring, controlling the rotation speed at 300-400 r / min, stirring for 10-20 min, then adding inorganic filler, increasing the rotation speed to 600-800 r / min, continuing to stir for 30-40 min, then adding self-healing capsules, reducing the rotation speed to 300-400 r / min, continuing to stir for 20-30 min, then sequentially adding pigments, fillers, defoamers, and leveling agents, maintaining the rotation speed at 300-400 r / min, stirring for 15-25 min, and then adjusting... Adjust the paint to a suitable viscosity to obtain the water-based paint; wherein the mass ratio of water-based acrylic resin emulsion, deionized water, inorganic filler, self-healing capsule, pigments and fillers, defoamer and leveling agent is 100:20-50:18-25:5-15:15-28:0.1-0.5:0.2-0.8; wherein the pigments and fillers are one or a mixture of several of titanium dioxide, iron oxide red, iron oxide yellow, carbon black, phthalocyanine blue, and phthalocyanine green; the defoamer is one or a mixture of several of fatty alcohols, fatty acid esters, organosilicon, and mineral oil; and the leveling agent is one or a mixture of several of acrylate copolymers, organosilicon, and fluoroalkyl esters.

[0028] In step S300, during the mixing and preparation process, the aqueous acrylic resin emulsion serves as the continuous phase in the system, and its molecular chains contain polar groups such as carboxyl and hydroxyl groups. The carboxyl groups and other groups on the surface of the rosin-modified calcium carbonate inorganic filler can bind to it through hydrogen bonds and other forces, enhancing the interfacial compatibility between the filler and the resin matrix, effectively preventing filler agglomeration, and ensuring its uniform dispersion in the resin system. The rosin-modified calcium carbonate inorganic filler fills the spaces between the resin molecular chains, forming a network-like support structure through the aforementioned interfacial interaction, which can improve the hardness, wear resistance, and other mechanical properties of the paint film. The resin, by encapsulating the filler to form a continuous film, ensures the integrity of the paint film. The wall material of the self-healing capsule is polyether-modified aminopolysiloxane, whose polyether segments have good compatibility with the aqueous resin, reducing the interfacial tension between the self-healing capsule and the resin matrix, allowing the capsule to be uniformly dispersed in the continuous resin phase. The amino groups on the capsule wall material and the carboxyl groups and other groups on the aqueous acrylic resin molecular chains can form weak interactions such as hydrogen bonds, preventing the capsule from settling in the system.

[0029] An environmentally friendly water-based paint is prepared using the environmentally friendly water-based paint preparation method described in any of the above technical solutions.

[0030] In this invention: octamethylcyclotetrasiloxane (purity ≥99.9%), N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane (purity ≥96%), 1,1,3,3-tetramethyldisiloxane (purity ≥99.9%), tetramethylammonium hydroxide (pentahydrate, 97%), polyethylene glycol diacrylate (PEGDA-600, 96%), chloroplatinic acid (AR, Pt≥37.5%), calcium carbonate (heavy calcium carbonate, particle size 1-5μm, analytical grade), rosin (containing more than 90% abietic acid, carboxyl content about 4.5mmol / g), butyl acrylate (analytical grade), styrene (analytical grade), hydroxyethyl acrylate (analytical grade), (meth)acrylic acid (analytical grade), disodium alkyl polyoxyethylene ether succinate monoester sulfonate (industrial grade), sodium 3-allyloxy-2-hydroxypropanesulfonate (industrial grade), ammonium persulfate (analytical grade), all reagents are commercially available.

[0031] Preparation Example 1-1 The preparation method of polyether-modified amino polysiloxane is as follows: A1. Under a nitrogen atmosphere, 80 parts by weight of octamethylcyclotetrasiloxane, 12 parts by weight of N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and 8 parts by weight of 1,1,3,3-tetramethyldisiloxane were added to a reactor. The temperature was raised to 55°C, and the mixture was stirred for 15 min. The temperature was then raised to 105°C and 0.08 parts by weight of tetramethylammonium hydroxide were added. The reaction was carried out for 5 h. After the reaction was completed, the temperature was raised to 145°C and the reaction was carried out for 20 min. After vacuum treatment for 2 h, hydrogen-containing amino silicone oil was obtained. A2. Add 60 parts by weight of hydrogen-containing amino silicone oil, 20 parts by weight of polyethylene glycol diacrylate and 30 parts by weight of isopropanol to the reactor, raise the temperature to 55°C, mix and stir for 15 min, then add 0.3 parts by weight of 2% chloroplatinic acid-isopropanol solution and react for 30 min. Obtain polyether-modified amino polysiloxane by vacuum distillation.

[0032] Preparation Examples 1-2 The preparation method of polyether-modified amino polysiloxane is as follows: A1. Under a nitrogen atmosphere, 70 parts by weight of octamethylcyclotetrasiloxane, 5 parts by weight of N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and 6 parts by weight of 1,1,3,3-tetramethyldisiloxane were added to a reactor. The temperature was raised to 50°C and stirred for 10 min. The temperature was then raised to 100°C and 0.05 parts by weight of tetramethylammonium hydroxide were added. The reaction was carried out for 4 h. After the reaction was completed, the temperature was raised to 140°C and the reaction was continued for 15 min. After vacuum treatment for 2 h, hydrogen-containing amino silicone oil was obtained. A2. Add 50 parts by weight of hydrogen-containing amino silicone oil, 10 parts by weight of polyethylene glycol diacrylate and 20 parts by weight of isopropanol to the reactor, raise the temperature to 50°C, mix and stir for 10 min, then add 0.1 parts by weight of 2% chloroplatinic acid-isopropanol solution and react for 20 min. Obtain polyether-modified amino polysiloxane by vacuum distillation.

[0033] Preparation Examples 1-3 The preparation method of polyether-modified amino polysiloxane is as follows: A1. Under a nitrogen atmosphere, 90 parts by weight of octamethylcyclotetrasiloxane, 15 parts by weight of N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and 10 parts by weight of 1,1,3,3-tetramethyldisiloxane were added to a reactor. The temperature was raised to 55°C and stirred for 20 min. The temperature was then raised to 105°C and 0.15 parts by weight of tetramethylammonium hydroxide were added. The reaction was carried out for 6 h. After the reaction was completed, the temperature was raised to 150°C and the reaction was continued for 25 min. After vacuum treatment for 2 h, hydrogen-containing amino silicone oil was obtained. A2. Add 70 parts by weight of hydrogen-containing amino silicone oil, 30 parts by weight of polyethylene glycol diacrylate and 40 parts by weight of isopropanol to the reactor, raise the temperature to 55°C, mix and stir for 20 min, then add 0.5 parts by weight of 2% chloroplatinic acid-isopropanol solution and react for 40 min. Obtain polyether-modified amino polysiloxane by vacuum distillation.

[0034] Preparation Examples 1-4 The preparation method of polyether-modified amino polysiloxane is as follows: A1. Under a nitrogen atmosphere, 85 parts by weight of octamethylcyclotetrasiloxane, 14 parts by weight of N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and 9 parts by weight of 1,1,3,3-tetramethyldisiloxane were added to a reactor. The temperature was raised to 55°C, and the mixture was stirred for 15 min. The temperature was then raised to 105°C and 0.12 parts by weight of tetramethylammonium hydroxide were added. The reaction was carried out for 5 h. After the reaction was completed, the temperature was raised to 145°C and the reaction was continued for 20 min. After vacuum treatment for 2 h, hydrogen-containing amino silicone oil was obtained. A2. Add 65 parts by weight of hydrogen-containing amino silicone oil, 25 parts by weight of polyethylene glycol diacrylate and 35 parts by weight of isopropanol to the reactor, raise the temperature to 55°C, mix and stir for 15 min, then add 0.35 parts by weight of 2% chloroplatinic acid-isopropanol solution and react for 30 min. Obtain polyether-modified amino polysiloxane by vacuum distillation.

[0035] Preparation Example 2-1 The preparation method of waterborne acrylic resin emulsion is as follows: B1. Add 60 parts by weight of butyl acrylate, 30 parts by weight of styrene, 3 parts by weight of hydroxyethyl acrylate and 3 parts by weight of (meth)acrylic acid to a reactor, mix evenly at room temperature, and then add to a solution composed of 120 parts by weight of water, 2 parts by weight of disodium alkyl polyoxyethylene ether succinate monosulfonate and 1.5 parts by weight of sodium 3-allyloxy-2-hydroxypropanesulfonate. Stir and emulsify to obtain a pre-emulsified monomer. B2. Add 100 parts by weight of water, 0.8 parts by weight of disodium alkyl polyoxyethylene ether succinate monoester sulfonate, 0.5 parts by weight of sodium 3-allyloxy-2-hydroxypropanesulfonate, and 0.2 parts by weight of ammonium persulfate to a reactor. Heat to 75°C, add 160 parts by weight of pre-emulsified monomer, and keep the reaction at this temperature for 30 minutes. Then, add 2 parts by weight of 10% ammonium persulfate solution dropwise. After the addition is complete, keep the reaction at this temperature for 3 hours. Cool to room temperature, adjust the pH to 6.5 with ammonia water, and filter through a 200-mesh sieve to obtain the aqueous acrylic resin emulsion.

[0036] Preparation Example 2-2 The preparation method of waterborne acrylic resin emulsion is as follows: B1. Add 50 parts by weight of butyl acrylate, 20 parts by weight of styrene, 2 parts by weight of hydroxyethyl acrylate and 1 part by weight of (meth)acrylic acid to the reactor, mix evenly at room temperature, and then add to a solution composed of 100 parts by weight of water, 1 part by weight of disodium alkyl polyoxyethylene ether succinate monosulfonate and 1 part by weight of sodium 3-allyloxy-2-hydroxypropanesulfonate, stir and emulsify to obtain a pre-emulsified monomer. B2. Add 80 parts by weight of water, 0.5 parts by weight of disodium alkyl polyoxyethylene ether succinate monoester sulfonate, 0.3 parts by weight of sodium 3-allyloxy-2-hydroxypropanesulfonate, and 0.15 parts by weight of ammonium persulfate to a reactor. Heat to 70°C, add 150 parts by weight of pre-emulsified monomer, and keep the reaction at this temperature for 20 minutes. Then, add 1.8 parts by weight of 10% ammonium persulfate solution dropwise. After the addition is complete, keep the reaction at this temperature for 2 hours. Cool to room temperature, adjust the pH to 6.5 with ammonia water, and filter through a 200-mesh sieve to obtain the aqueous acrylic resin emulsion.

[0037] Preparation Examples 2-3 The preparation method of waterborne acrylic resin emulsion is as follows: B1. Add 70 parts by weight of butyl acrylate, 40 parts by weight of styrene, 5 parts by weight of hydroxyethyl acrylate and 5 parts by weight of (meth)acrylic acid to the reactor, mix evenly at room temperature, and then add to a solution composed of 150 parts by weight of water, 3 parts by weight of disodium alkyl polyoxyethylene ether succinate monosulfonate and 2 parts by weight of sodium 3-allyloxy-2-hydroxypropanesulfonate, stir and emulsify to obtain a pre-emulsified monomer. B2. Add 120 parts by weight of water, 1.2 parts by weight of disodium alkyl polyoxyethylene ether succinate monoester sulfonate, 0.8 parts by weight of sodium 3-allyloxy-2-hydroxypropanesulfonate, and 0.35 parts by weight of ammonium persulfate to a reactor, heat to 75°C, add 180 parts by weight of pre-emulsified monomer, keep the reaction at this temperature for 40 min, then add 3.2 parts by weight of 10% ammonium persulfate solution dropwise, keep the reaction at this temperature for 4 h after the addition is complete, cool to room temperature, adjust the pH to 6.5 with ammonia water, and filter through a 200-mesh sieve to obtain the aqueous acrylic resin emulsion.

[0038] Preparation Examples 2-4 The preparation method of waterborne acrylic resin emulsion is as follows: B1. Add 65 parts by weight of butyl acrylate, 35 parts by weight of styrene, 4 parts by weight of hydroxyethyl acrylate and 3.5 parts by weight of (meth)acrylic acid to a reactor, mix evenly at room temperature, and then add to a solution composed of 135 parts by weight of water, 2.5 parts by weight of disodium alkyl polyoxyethylene ether succinate monoester sulfonate and 1.8 parts by weight of sodium 3-allyloxy-2-hydroxypropanesulfonate. Stir and emulsify to obtain a pre-emulsified monomer. B2. Add 110 parts by weight of water, 1 part by weight of disodium alkyl polyoxyethylene ether succinate monoester sulfonate, 0.6 parts by weight of sodium 3-allyloxy-2-hydroxypropanesulfonate, and 0.25 parts by weight of ammonium persulfate to a reactor. Heat to 75°C, add 170 parts by weight of pre-emulsified monomer, and keep the reaction at this temperature for 30 minutes. Then, add 2.5 parts by weight of 10% ammonium persulfate solution dropwise. After the addition is complete, keep the reaction at this temperature for 3 hours. Cool to room temperature, adjust the pH to 6.5 with ammonia water, and filter through a 200-mesh sieve to obtain the aqueous acrylic resin emulsion.

[0039] Example 1 S1. Mix 30 parts by weight of tung oil, 10 parts by weight of linseed oil and 10 parts by weight of the polyether-modified amino polysiloxane prepared in Preparation Example 1-1 to obtain a homogeneous oil phase; add 10 parts by weight of the oil phase to 40 parts by weight of deionized water containing 1 part by weight of Tween-80, stir at 1500 rpm for 20 min to form an oil-in-water emulsion, add 0.1 parts by weight of tetraethyl orthosilicate, raise the temperature to 50°C, reduce the stirring speed to 500 rpm and stir for 3 h. After the reaction is completed, centrifuge, wash 3 times with deionized water, and dry at 40°C for 4 h to obtain a self-healing capsule. S2. Add 10 parts by weight of calcium carbonate and 0.1 parts by weight of sodium hexametaphosphate to 15 parts by weight of deionized water, and stir at 2000 rpm for 20-40 min to obtain a calcium carbonate suspension; heat 6 parts by weight of rosin until melted, add 0.4 parts by weight of triethanolamine and stir evenly to obtain a mixed solution, add it dropwise to 10 parts by weight of calcium carbonate suspension, control the reaction temperature at 70℃, stir and react for 2 h, filter after the reaction, wash 3 times with deionized water, and dry at 40℃ for 4 h to obtain rosin-modified calcium carbonate, which is the inorganic filler; S3. Add 100 parts by weight of the aqueous acrylic resin emulsion prepared in Preparation Example 2-1 to the reactor. Add 30 parts by weight of deionized water while stirring. Control the rotation speed at 400 r / min and stir for 15 min. Then add 20 parts by weight of inorganic filler and increase the rotation speed to 700 r / min. Continue stirring for 40 min. Then add 10 parts by weight of self-healing capsules and decrease the rotation speed to 400 r / min. Continue stirring for 30 min. Then add 18 parts by weight of titanium dioxide, 0.3 parts by weight of octanol and 0.5 parts by weight of dihydroxytrifluoroacrylate in sequence. Maintain the rotation speed at 400 r / min and stir for 20 min. Then use hydroxyethyl cellulose to adjust the paint to a suitable viscosity to obtain the aqueous paint.

[0040] Example 2 This embodiment differs from Embodiment 1 in the following ways: In step S1, 25 parts by weight of tung oil, 5 parts by weight of linseed oil and 10 parts by weight of the polyether-modified amino polysiloxane prepared in Preparation Examples 1-2 are mixed to obtain a homogeneous oil phase; 10 parts by weight of the oil phase are added to 30 parts by weight of deionized water containing 0.5 parts by weight of Tween-80 to form an oil-in-water emulsion, and 0.1 parts by weight of tetraethyl orthosilicate are added thereto. In step S2, 10 parts by weight of calcium carbonate and 0.05 parts by weight of sodium hexametaphosphate are added to 10 parts by weight of deionized water to obtain a calcium carbonate suspension; 5 parts by weight of rosin are heated to melt, and 0.2 parts by weight of triethanolamine are added and stirred evenly to obtain a mixture, which is then added dropwise to 8 parts by weight of calcium carbonate suspension. In step S3, 100 parts by weight of the aqueous acrylic resin emulsion prepared in Preparation Example 2-2 are added to the reactor, 20 parts by weight of deionized water are added while stirring, 18 parts by weight of inorganic filler are added, 5 parts by weight of self-healing capsules are added, and then 15 parts by weight of titanium dioxide, 0.1 parts by weight of octanol and 0.2 parts by weight of dihydroxytrifluoroacrylate are added in sequence.

[0041] Example 3 This embodiment differs from Embodiment 1 in the following ways: In step S1, 40 parts by weight of tung oil, 10 parts by weight of linseed oil and 10 parts by weight of the polyether-modified amino polysiloxane prepared in Preparation Examples 1-3 are mixed to obtain a homogeneous oil phase; 10 parts by weight of the oil phase are added to 50 parts by weight of deionized water containing 1.5 parts by weight of Tween-80 to form an oil-in-water emulsion, and 0.15 parts by weight of tetraethyl orthosilicate are added thereto. In step S2, 10 parts by weight of calcium carbonate and 0.12 parts by weight of sodium hexametaphosphate are added to 18 parts by weight of deionized water to obtain a calcium carbonate suspension; 8 parts by weight of rosin are heated to melt, and 0.6 parts by weight of triethanolamine are added and stirred evenly to obtain a mixture, which is then added dropwise to 11 parts by weight of calcium carbonate suspension. In step S3, 100 parts by weight of the aqueous acrylic resin emulsion prepared in Preparation Examples 2-3 are added to the reactor, 50 parts by weight of deionized water are added while stirring, 25 parts by weight of inorganic filler are added, 15 parts by weight of self-healing capsules are added, and then 28 parts by weight of titanium dioxide, 0.5 parts by weight of octanol and 0.8 parts by weight of dihydroxytrifluoroacrylate are added in sequence.

[0042] Example 4 This embodiment differs from Embodiment 1 in the following ways: In step S1, 30 parts by weight of tung oil, 10 parts by weight of linseed oil and 10 parts by weight of the polyether-modified amino polysiloxane prepared in Preparation Examples 1-4 are mixed to obtain a homogeneous oil phase; 10 parts by weight of the oil phase are added to 45 parts by weight of deionized water containing 1.3 parts by weight of Tween-80 to form an oil-in-water emulsion, and 0.12 parts by weight of tetraethyl orthosilicate are added thereto. In step S2, 10 parts by weight of calcium carbonate and 0.11 parts by weight of sodium hexametaphosphate are added to 16 parts by weight of deionized water to obtain a calcium carbonate suspension; 7 parts by weight of rosin are heated to melt, and 0.5 parts by weight of triethanolamine are added and stirred evenly to obtain a mixture, which is then added dropwise to 9 parts by weight of calcium carbonate suspension. In step S3, 100 parts by weight of the aqueous acrylic resin emulsion prepared in Preparation Examples 2-4 are added to the reactor, 40 parts by weight of deionized water are added while stirring, 22 parts by weight of inorganic filler are added, 12 parts by weight of self-healing capsules are added, and then 22 parts by weight of titanium dioxide, 0.4 parts by weight of octanol and 0.6 parts by weight of dihydroxytrifluoroacrylate are added in sequence.

[0043] Comparative Example 1 Compared with Example 1, in step S1, the polyether-modified aminopolysiloxane prepared in Preparation Example 1-1 was replaced with polysiloxane.

[0044] Comparative Example 2 Compared with Example 1, in step S3, the aqueous acrylic resin emulsion prepared in Preparation Example 2-1 was replaced with a commercially available aqueous acrylic emulsion (BASF, acrylic emulsion, Joncryl PRO 1552).

[0045] Comparative Example 3 Compared with Example 1, in step S1, the polyether-modified amino polysiloxane prepared in Preparation Example 1-1 was replaced with polysiloxane; in step S3, the aqueous acrylic resin emulsion prepared in Preparation Example 2-1 was replaced with a commercially available aqueous acrylic emulsion.

[0046] Comparative Example 4 Compared with Example 1, this comparative example does not modify calcium carbonate; instead, calcium carbonate is used directly as an inorganic filler.

[0047] Comparative Example 5 Compared with Example 1, this comparative example does not include the addition of self-healing capsules during the preparation process in step S3.

[0048] Comparative Example 6 Compared with Example 1, this comparative example does not modify calcium carbonate, but directly uses calcium carbonate as an inorganic filler; in step S3, the aqueous acrylic resin emulsion prepared in Example 2-1 is replaced with a commercially available aqueous acrylic emulsion; and no self-healing capsules are added during the preparation process.

[0049] The water-based paints prepared in Examples 1 to 4 and Comparative Examples 1 to 6 were subjected to relevant performance tests: Self-healing performance test: The test results are shown in Table 1, according to the method specified in GB / T1743-89.

[0050] Table 1 Self-healing performance test results Adhesion test: The test results are shown in Table 2, according to the method specified in GB / T 9286-1998.

[0051] Hardness test: The test results are shown in Table 2, according to the method specified in GB / T 6739-2006.

[0052] Abrasion resistance test: The test results are shown in Table 2, according to the method specified in GB / T 1768-2006.

[0053] Table 2 Results of Adhesion, Hardness, and Abrasion Resistance Tests The test results above show that the water-based paint prepared by this invention has good self-healing properties, strong adhesion, and high wear resistance.

[0054] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0055] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing an environmentally friendly water-based paint, characterized by, Includes the following steps: S100: A self-healing capsule is prepared by using polyether-modified aminopolysiloxane as the shell material and a drying oil self-healing agent as the core material. S200: Inorganic fillers are prepared using natural resins containing carboxyl groups and inorganic carbonates as raw materials. S300: The water-based paint is obtained by mixing and stirring water-based acrylic resin emulsion, self-healing capsules, inorganic fillers, pigments, defoamers, and leveling agents; wherein the mass ratio of water-based acrylic resin emulsion, inorganic fillers, self-healing capsules, pigments, defoamers, and leveling agents is 100:18-25:5-15:15-28:0.1-0.5:0.2-0.

8. The preparation method of polyether-modified amino polysiloxane is as follows: A1. Under an inert atmosphere, octamethylcyclotetrasiloxane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and 1,1,3,3-tetramethyldisiloxane are added to a reactor. The temperature is raised to 50-55℃, and the mixture is stirred for 10-20 min. The temperature is then raised to 100-105℃ and tetramethylammonium hydroxide is added. The reaction is carried out for 4-6 h. After the reaction is completed, the temperature is raised to 140-150℃ and the reaction is continued for 15-25 min. After vacuum treatment, hydrogen-containing amino silicone oil is obtained. A2. Add hydrogen-containing amino silicone oil, polyethylene glycol diacrylate and isopropanol to the reactor, raise the temperature to 50-55℃, mix and stir for 10-20 min, then add chloroplatinic acid-isopropanol solution and react for 20-40 min. Obtain polyether modified amino polysiloxane by vacuum distillation. The drying oil self-healing agent is obtained by mixing tung oil and linseed oil in a mass ratio of 2-5:

1.

2. The method for preparing an environmentally friendly water-based paint according to claim 1, characterized in that, Step S100 specifically includes: S110. A uniform oil phase is obtained by mixing a dry oil self-healing agent with a polyether-modified amino polysiloxane. S120. Add the oil phase to deionized water containing emulsifier, and shear at high speed for 15-25 min to form an oil-in-water emulsion. Add a crosslinking agent to the emulsion, raise the temperature to 45-55℃, reduce the stirring rate and stir for 2-4 h. After the reaction is completed, centrifuge, wash and dry to obtain the self-healing capsule.

3. The method of claim 1, wherein the water-based paint is prepared by adding the water-based paint base material, the water-based paint additive, and the water-based paint additive to the water-based paint base material, and stirring the mixture. Step S200 specifically includes: S210. Add calcium carbonate and dispersant to deionized water and stir at high speed for 20-40 minutes to obtain a calcium carbonate suspension. S220. Heat rosin until it melts, add triethanolamine and stir until homogeneous to obtain a mixture. Add the mixture dropwise to a calcium carbonate suspension, control the reaction temperature at 60-80℃, and stir for 1-2 hours. After the reaction is complete, filter, wash and dry to obtain rosin-modified calcium carbonate, which is the inorganic filler.

4. The method of claim 1, wherein the water-based paint is prepared by adding 0.1 to 1.0 parts by weight of the compound of formula (1) to 100 parts by weight of the water-based paint. The preparation method of waterborne acrylic resin emulsion is as follows: B1. Add butyl acrylate, styrene, hydroxyethyl acrylate and (meth)acrylic acid to the reactor, mix them evenly at room temperature, and then add them to a solution composed of water, disodium alkyl polyoxyethylene ether succinate monosulfonate and sodium 3-allyloxy-2-hydroxypropanesulfonate. Stir and emulsify to obtain a pre-emulsified monomer. B2. Add water, disodium alkyl polyoxyethylene ether succinate monoester sulfonate, sodium 3-allyloxy-2-hydroxypropanesulfonate, and ammonium persulfate to the reactor, heat to 70-75°C, add the pre-emulsified monomer, keep the reaction at this temperature for 20-40 minutes, then add the ammonium persulfate solution, keep the reaction at this temperature for 2-4 hours after the addition is complete, cool to room temperature, adjust the pH, and filter to obtain the aqueous acrylic resin emulsion.

5. The method of claim 1, wherein the water-based paint is prepared by adding 0.1 to 1.0 parts by weight of the compound of formula (1) to 100 parts by weight of the water-based paint. Step S300 specifically includes: adding water-based acrylic resin emulsion to the reactor, adding deionized water while stirring, controlling the rotation speed at 300-400 r / min, stirring for 10-20 min, then adding inorganic filler, increasing the rotation speed to 600-800 r / min, continuing to stir for 30-40 min, then adding self-healing capsules, reducing the rotation speed to 300-400 r / min, continuing to stir for 20-30 min, then adding pigments, fillers, defoamers, and leveling agents in sequence, maintaining the rotation speed at 300-400 r / min, stirring for 15-25 min, and then adjusting the paint to a suitable viscosity to obtain the water-based paint.

6. An environmentally friendly water-based paint, characterized by, It is prepared using the environmentally friendly water-based paint preparation method as described in any one of claims 1-5.

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