Environment-friendly water-based paint and preparation method thereof

Abstract

The invention belongs to the technical field of water-based paint preparation, and particularly relates to environment-friendly water-based paint and a preparation method thereof. The water-based paint is obtained by mixing and stirring the raw materials of the water-based acrylic resin emulsion, the self-healing capsule, the inorganic filler, the pigment filler, the defoaming agent and the flatting agent. Wherein polyether modified amino polysiloxane is used as a shell material; the self-healing capsule is prepared by taking a natural dry oil self-healing agent as a core material, and when a paint film has cracks and is impacted by external force, the capsule is broken to release the core material, so that accurate positioning repair can be realized.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of water-based paint preparation, and particularly relates to an environmentally-friendly water-based paint and a preparation method thereof. BACKGROUND

[0002] Paint, as a kind of coating, refers to a kind of liquid or solid material that is coated on the surface of an object and has a solid film with protective, decorative or special properties. Traditional paint is widely used due to its excellent performance and convenient application. However, it uses organic solvents as a dispersion medium and a diluent, which releases a large amount of volatile organic compounds during production, application and drying, causing serious environmental, health and safety problems. Therefore, water-based paint has emerged. Water-based paint uses water as the main dispersion medium and diluent, but it has shortcomings in terms of adhesion, hardness and other properties.

[0003] A modified inorganic particle doped water-based paint and a preparation method thereof are disclosed in Chinese Patent No. CN119463601B. The raw materials include water-based acrylic resin, modified inorganic particles, polyvinyl alcohol, defoaming agent, and dispersant, which are mixed and stirred to obtain the paint. The paint uses polyimide particles instead of nano-titanium dioxide as a flame-retardant component, and the polyimide particles and nano-titanium dioxide particles are treated at high temperature to enhance the flame-retardant property of polyimide. Carbon quantum dots and graphene quantum dots are generated to increase the antibacterial durability of the water-based paint. Chinese Patent No. CN118772742B discloses a rust-proof water-based paint for AGV forklifts and a preparation method thereof. The paint is prepared by mixing A component, B component and C component. The A component includes water-based epoxy resin, defoaming agent, leveling agent, wetting agent, dispersant, wear-resistant filler, rust inhibitor, anti-settling agent, and deionized water. The B component includes curing agent and water. The C component is zinc powder. The use of organosilicon polyether grafted modified epoxy resin combined with low molecular weight and low epoxy equivalent weight epoxy resin can effectively improve the toughness and low temperature resistance of the epoxy resin film. The use of spherical fillers modified by epoxy-based silane coupling agent and carboxyl benzotriazole can compensate for the loss of wear resistance of the paint film caused by the use of the aforementioned epoxy resin, achieving a balance between the toughness and hardness, low temperature resistance and wear resistance of the paint film. However, during long-term use, the paint will inevitably develop some micro-cracks, which are difficult to detect in the early stages. The continuous expansion of the cracks will directly affect the service life of the material. Therefore, how to effectively prolong the service life of the paint has become a research focus. SUMMARY

[0004] To solve at least one of the above problems, the present application provides a preparation method of an environmentally-friendly water-based paint, comprising the following steps: S100, preparing self-healing capsules from polyether modified amino polysiloxane and dry oil self-healing agent raw materials; S200, preparing inorganic fillers by using raw materials containing carboxyl-containing natural resin and inorganic carbonate; S300, mixing and stirring raw materials of water-based acrylic resin emulsion, self-healing capsules, inorganic fillers, pigments and fillers, defoaming agents and leveling agents to obtain the water-based paint.

[0005] Further, the preparation method of the polyether-modified amino polysiloxane is: A1, under inert atmosphere, octamethylcyclotetrasiloxane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and 1,1,3,3-tetramethyldisiloxane are added into a reactor, the temperature is raised to 50-55℃, mixed and stirred for 10-20min, the temperature is continuously raised to 100-105℃ and tetramethylammonium hydroxide is added, the reaction is carried out for 4-6h, after the reaction is completed, the temperature is raised to 140-150℃, the reaction is continuously carried out for 15-25min, and then hydrogen-containing amino silicone oil is obtained after vacuum treatment; A2, hydrogen-containing amino silicone oil, polyethylene glycol diacrylate and isopropyl alcohol are added into a reactor, the temperature is raised to 50-55℃, mixed and stirred for 10-20min, chloroplatinic acid-isopropyl alcohol solution is further added, the reaction is carried out for 20-40min, and then polyether-modified amino polysiloxane is obtained by reduced pressure distillation.

[0006] Further, the step S100 specifically comprises: S110, mixing the drying oil-based self-healing agent with the polyether-modified amino polysiloxane to obtain a uniform oil phase; S120, adding the oil phase into deionized water containing an emulsifier, high-speed shearing for 15-25min to form an oil-in-water emulsion, adding a crosslinking agent thereto, raising the temperature to 45-55℃, reducing the stirring speed and stirring for 2-4h, and then obtaining the self-healing capsules after centrifugation, washing and drying.

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

[0008] Further, the step S200 specifically comprises: S210, adding calcium carbonate and a dispersing agent into deionized water, high-speed stirring for 20-40min to obtain a calcium carbonate suspension; S220, heating rosin to melting, adding triethanolamine and stirring uniformly to obtain a mixed solution, adding the mixed solution dropwise into the calcium carbonate suspension, controlling the reaction temperature to be 60-80℃, stirring for 1-2h, and then obtaining rosin-modified calcium carbonate, i.e. the inorganic filler, after filtration, washing and drying.

[0009] Further, the preparation method of the water-based acrylic resin emulsion is: B1, add butyl acrylate, styrene, hydroxyethyl acrylate and (meth) acrylic acid into the reactor, mix uniformly at room temperature, and then add into a solution composed of water, alkyl polyoxyethylene ether succinic acid monoester disodium sulfonate and 3-allyloxy-2-hydroxypropane sulfonic acid sodium, emulsify by stirring to obtain pre-emulsified monomers; B2, add water, alkyl polyoxyethylene ether succinic acid monoester disodium sulfonate, 3-allyloxy-2-hydroxypropane sulfonic acid sodium and ammonium persulfate into the reactor, heat to 70-75 DEG C, add pre-emulsified monomers, and react for 20-40 min, then add ammonium persulfate solution, react for 2-4 h after the addition is completed, cool to room temperature, adjust pH, and filter to obtain the aqueous acrylic resin emulsion.

[0010] Further, the step S300 specifically comprises: adding the aqueous acrylic resin emulsion into the reactor, adding deionized water under stirring, controlling the rotating speed at 300-400 r / min, stirring for 10-20 min, then adding inorganic fillers, increasing the rotating speed to 600-800 r / min, and continuing to stir for 30-40 min, then adding in self-healing capsules, reducing the rotating speed to 300-400 r / min, and continuing to stir for 20-30 min, then adding in color fillers, defoaming agent and leveling agent in sequence, maintaining the rotating speed at 300-400 r / min, stirring for 15-25 min, and then adjusting the paint to a proper viscosity to obtain the water-based paint.

[0011] The water-based paint is environmentally friendly and is prepared by the preparation method of the water-based paint.

[0012] The present application has the following advantages: In the preparation process of the self-healing capsules, hydrogen-containing amino silicone oil and polyethylene glycol diacrylate are used as raw materials, chloroplatinic acid is used as a catalyst, polyether modified amino polysiloxane is prepared as a shell material, and natural drying oil self-healing agent is used as a core material, so that the self-healing capsules are prepared.

[0013] In the preparation of the inorganic fillers, rosin is used to modify calcium carbonate, and the rosin molecular chains are adsorbed on the surface of calcium carbonate by electrostatic attraction, so that the rosin molecular chains on the surface of the modified calcium carbonate form steric hindrance, hinder the agglomeration between particles, and improve the dispersibility in the paint.

[0014] The water-based acrylic resin emulsion containing hydroxyl groups is prepared from butyl acrylate, styrene, hydroxyethyl acrylate and (methyl) acrylic acid as raw materials through emulsification and polymerization, and contains polar groups such as carboxyl and hydroxyl groups in the molecular chain, which can form hydrogen bonds and other actions with the polar groups on the surface of rosin modified calcium carbonate inorganic filler and self-healing capsules, thereby enhancing the interfacial compatibility with the resin matrix and being helpful to dispersion. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0016] Traditional paint has long occupied the market due to its good performance, but the volatile organic compounds contained therein have certain harm to the environment and human health. Therefore, environmentally friendly water-based paint gradually attracts attention because water is used as a diluent. Although water-based paint is continuously developing, it still needs to be improved in terms of hardness, wear resistance, self-repairing ability and the like. Therefore, the present application provides a preparation method of environmentally friendly water-based paint, comprising the following steps: S100, preparing self-healing capsules from raw materials of polyether modified amino polysiloxane and dry oil type self-healing agent; S200, preparing inorganic fillers from raw materials of carboxyl-containing natural resin and inorganic carbonate; S300, mixing and stirring raw materials of water-based acrylic resin emulsion, self-healing capsules, inorganic fillers, pigments and fillers, defoaming agent and leveling agent to obtain the water-based paint.

[0017] The preparation method of the polyether modified amino polysiloxane is as follows: A1, under an inert atmosphere, octamethylcyclotetrasiloxane, N-(β-aminoethyl)-γ-aminopropyl methyl dimethoxy silane and 1,1,3,3-tetramethyl disiloxane are added into a reactor, the temperature is raised to 50-55 DEG C, and mixed and stirred for 10-20 min, then the temperature is continuously raised to 100-105 DEG C, and tetramethyl ammonium hydroxide is added, and reacted for 4-6 h, after the reaction is completed, the temperature is raised to 140-150 DEG C, and the reaction is continuously carried out for 15-25 min, then vacuum treatment is carried out to obtain hydrogen-containing amino silicone oil; wherein the mass ratio of octamethylcyclotetrasiloxane, N-(β-aminoethyl)-γ-aminopropyl methyl dimethoxy silane, 1,1,3,3-tetramethyl disiloxane and tetramethyl ammonium hydroxide is 70-90:5-15:6-10:0.05-0.15; A2, hydrogen-containing amino silicone oil, polyethylene glycol diacrylate and isopropyl alcohol are added into the reactor, the temperature is raised to 50-55℃, mixed and stirred for 10-20 min, then 2% chloroplatinic acid-isopropyl alcohol solution is added and reacted for 20-40 min, and then polyether modified amino polysiloxane is obtained by reduced pressure distillation; wherein the mass ratio of hydrogen-containing amino silicone oil, polyethylene glycol diacrylate, isopropyl alcohol and chloroplatinic acid-isopropyl alcohol solution is 50-70:10-30:20-40:0.1-0.5.

[0018] In the above steps, the polysiloxane is a high molecular compound with siloxane bond as the main chain and silicon atom connected with organic groups, which has excellent high and low temperature resistance, radiation resistance and weather resistance, and can improve the flexibility of the coating and reduce the cracking of the coating caused by thermal expansion and cold contraction of the substrate after being mixed with the film-forming material in the paint. However, its surface energy is low, and it is easy to agglomerate and settle in the polar water-based paint system due to insufficient compatibility, resulting in uneven dispersion. Therefore, in the present application, 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. The polyether group is introduced into the side chain of the polysiloxane structure to improve its hydrophilicity and enhance its binding force with water-based acrylic resin emulsion and other substances.

[0019] Specifically, step S100 includes: S110, mixing the dry oil-based self-healing agent with the polyether modified amino polysiloxane to obtain a uniform oil phase; wherein the mass ratio of the dry oil-based self-healing agent to the polyether modified amino polysiloxane is 3-5:1; S120, adding the oil phase to deionized water containing an emulsifier, high-speed shearing for 15-25 min to form an oil-in-water emulsion, adding a crosslinking agent thereto, raising the temperature to 45-55℃, reducing the stirring speed and stirring for 2-4 h, and then centrifuging, washing and drying to obtain the self-healing capsule; wherein the mass ratio of the oil phase, the emulsifier, the deionized water and the crosslinking agent is 10:0.5-1.5:30-50:0.05-0.15.

[0020] In the above steps, the paint will inevitably have some micro-cracks during long-term use due to wear, aging and other problems, and these micro-cracks are difficult to be found in time, and the continuous expansion of the cracks will directly affect the service life of the material, so in the present application, a self-healing agent is added during preparation to give it certain self-repairing ability. Under the premise of environmental friendliness, renewable natural plant oil resources are used as self-healing agents in the present application. However, if the dry oil self-healing agent is directly added as one of the raw materials during the preparation of the paint, the oxidation may be triggered in advance due to the trace amount of oxygen in the system, resulting in the separation of the paint or even gelation, and the self-healing agent may flow too fast when repairing, which may cause waste beyond the crack range. Therefore, in the present application, polyether-modified amino polysiloxane is used as the shell material, and the dry oil self-healing agent is used as the core material to prepare self-healing capsules. After the capsules are prepared, the shell material can isolate the self-healing agent from the contact with the external oxygen, moisture and other active components, thereby avoiding premature oxidation, and when the self-healing agent is wrapped in the shell material, the capsules will only be broken to release the core material when the paint film has cracks or is impacted by external force, thereby achieving precise positioning repair. In addition, the shell material is prepared by using polyether-modified amino polysiloxane, which makes the prepared self-healing capsules stably dispersed in the aqueous medium, and can reduce the defects such as shrinkage holes and pinholes caused by uneven distribution. At the same time, the flexible structure of the polyether segment can reduce the interfacial stress between the shell material and the core material, so that the self-healing capsules are more stable during storage and transportation.

[0021] The dry oil self-healing agent is one or a mixture of several of linseed oil, tung oil, catalpa oil, perilla oil and hemp seed oil.

[0022] In the above steps, the tung oil acid triglyceride component in tung oil is easily hydrolyzed into tung oil acid, which contains multiple conjugated double bonds and has strong polymerization ability. The polymer formed by the polymerization of tung oil acid and oxygen can repair the substrate, but the cured paint film is brittle and easy to produce secondary cracks due to stress shrinkage. Linseed oil contains a large amount of unsaturated fatty acids, and the carbon-carbon double bond is easy to be oxidized. The substance formed after oxidation forms a new protective film to repair the damaged area. Although the curing speed is moderate and the flexibility is good, the initial repair efficiency is low. Therefore, the present application uses a mixture of tung oil and linseed oil as a self-healing agent. The rapid crosslinking of tung oil fills the initially formed cracks, and the slow polymerization of linseed oil relieves the internal stress by molecular chain entanglement, so that the repair layer is not easy to be brittle.

[0023] The step S200 specifically comprises: S210, adding calcium carbonate and dispersant in deionized water, stirring at high speed for 20-40 min to obtain calcium carbonate suspension; wherein the mass ratio of deionized water, calcium carbonate and dispersant is 10-18:10:0.05-0.12; S220, heating rosin to melt, adding triethanolamine to stir uniformly to obtain a mixture, adding the mixture dropwise into the calcium carbonate suspension, controlling the reaction temperature to be 60-80℃, stirring for 1-2h, after the reaction is completed, filtering, washing and drying to obtain rosin modified calcium carbonate, which is the inorganic filler; wherein 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 inorganic filler, which is low in cost, widely available and harmless to human body; in the application of paint, it can form a skeleton support in the paint film to improve hardness and wear resistance. However, it has hydrophilicity and oleophobicity, and the surface energy is relatively large, so it is difficult to disperse uniformly in paint. Therefore, the surface of calcium carbonate is modified by rosin, and the rosin molecular chain is adsorbed on the surface of calcium carbonate by electrostatic attraction. The rosin molecular chain on the surface of modified calcium carbonate forms steric hindrance, which hinders the agglomeration between particles, improves the dispersibility in paint, and enhances the compatibility with water-based resin, thereby improving the stability and film performance of water-based paint.

[0025] The preparation method of the water-based acrylic resin emulsion is as follows: B1, adding butyl acrylate, styrene, hydroxyethyl acrylate and (meth) acrylic acid into a reactor, mixing uniformly at room temperature, and then adding into a solution composed of water, alkyl polyoxyethylene ether succinic acid monoester disodium sulfonate and 3-allyloxy-2-hydroxypropane sulfonic acid sodium, stirring and emulsifying to obtain a pre-emulsified monomer; wherein the mass ratio of butyl acrylate, styrene, hydroxyethyl acrylate, (meth) acrylic acid, water, alkyl polyoxyethylene ether succinic acid monoester disodium sulfonate and 3-allyloxy-2-hydroxypropane sulfonic acid sodium is 50-70:20-40:2-5:1-5:100-150:1-3:1-2; B2, adding water, alkyl polyoxyethylene ether succinic acid monoester disodium sulfonate, 3-allyloxy-2-hydroxypropane sulfonic acid sodium and ammonium persulfate into a reactor, heating to 70-75℃, adding the pre-emulsified monomer, and keeping the temperature for 20-40 min, then adding 10% ammonium persulfate solution, keeping the temperature for 2-4h after the addition is completed, cooling to room temperature, adjusting the pH, and filtering to obtain the water-based acrylic resin emulsion; wherein the mass ratio of water, alkyl polyoxyethylene ether succinic acid monoester disodium sulfonate, 3-allyloxy-2-hydroxypropane sulfonic acid sodium, ammonium persulfate, pre-emulsified monomer, 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, (meth)acrylic acid are used as raw materials, a pre-emulsified monomer is obtained by stirring and emulsifying after adding a composite emulsifier, and then an aqueous acrylic resin emulsion containing hydroxyl groups is obtained by polymerization.

[0027] In the step S300, the aqueous acrylic resin emulsion is added into the reactor, deionized water is added under stirring, the stirring speed is controlled at 300-400 r / min, stirring is performed for 10-20 min, then the inorganic filler is added, the stirring speed is increased to 600-800 r / min, and stirring is continued for 30-40 min, then the self-healing capsule is added, the stirring speed is reduced to 300-400 r / min, and stirring is continued for 20-30 min, then the color filler, defoaming agent and leveling agent are added in sequence, the stirring speed is maintained at 300-400 r / min, stirring is performed for 15-25 min, then the paint is adjusted to the appropriate viscosity, and the aqueous paint is obtained; the mass ratio of the aqueous acrylic resin emulsion, deionized water, inorganic filler, self-healing capsule, color filler, defoaming agent and leveling agent is 100:20-50:18-25:5-15:15-28:0.1-0.5:0.2-0.8; the color filler is one or a mixture of several of titanium dioxide, red iron oxide, yellow iron oxide, carbon black, phthalocyanine blue and phthalocyanine green; the defoaming agent is one or a mixture of several of fatty alcohol, fatty acid ester, silicone and mineral oil; and the leveling agent is one or a mixture of several of acrylate copolymer, silicone and fluoroalkyl ester.

[0028] In the mixing preparation process of the step S300, the aqueous acrylic resin emulsion is the continuous phase in the system, and contains polar groups such as carboxyl and hydroxyl in the molecular chain. The carboxyl and other groups contained on the surface of the rosin modified calcium carbonate inorganic filler can be combined with the resin matrix through hydrogen bonds and other forces, which enhances the interfacial compatibility of the filler and the resin matrix, effectively avoids the agglomeration of the filler, and ensures the uniform dispersion of the filler in the resin system. The rosin modified calcium carbonate inorganic filler is filled between the resin molecular chains, and forms a network-like support structure on the resin through the above-mentioned interfacial action, which can improve the mechanical properties such as hardness and wear resistance of the paint film. The resin forms a continuous film by wrapping the filler, which ensures the integrity of the paint film. The wall material of the self-healing capsule is polyether modified amino polysiloxane, which has good compatibility with the aqueous resin, can reduce the interfacial tension between the self-healing capsule and the resin matrix, and makes the capsule uniformly dispersed in the resin continuous phase; the amino groups on the capsule wall material can form hydrogen bonds and other weak interactions with the carboxyl groups and other groups on the molecular chain of the aqueous acrylic resin, which avoids the sedimentation of the capsule in the system.

[0029] An environmentally friendly aqueous paint is prepared by the preparation method of the environmentally friendly aqueous paint according to any one of the above technical solutions.

[0030] In the present application: 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 1-5 μm, analytical pure), rosin (containing more than 90% abietic acid, carboxyl content about 4.5 mmol / g), butyl acrylate (analytical pure), styrene (analytical pure), hydroxyethyl acrylate (analytical pure), (methyl) acrylic acid (analytical pure), alkyl polyoxyethylene ether succinate monoester disodium sulfonate (industrial grade), 3-allyloxy-2-hydroxypropane sulfonic acid sodium (industrial grade), ammonium persulfate (analytical pure), all reagents are ordinary commercially available.

[0031] Preparation Example 1-1 The preparation method of the polyether-modified aminosilicone is as follows: A1, under 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 into a reactor, the temperature was raised to 55°C, mixed and stirred for 15 min, the temperature was continuously raised to 105°C and 0.08 parts by weight of tetramethylammonium hydroxide was added, reacted for 5 h, after the reaction was completed, the temperature was raised to 145°C and reacted for another 20 min, after vacuum treatment for 2 h, hydrogen-containing aminosilicone oil was obtained; A2, 60 parts by weight of hydrogen-containing aminosilicone oil, 20 parts by weight of polyethylene glycol diacrylate and 30 parts by weight of isopropyl alcohol were added into a reactor, the temperature was raised to 55°C, mixed and stirred for 15 min, 0.3 parts by weight of 2% chloroplatinic acid-isopropyl alcohol solution was added and reacted for 30 min, polyether-modified aminosilicone was obtained by vacuum distillation.

[0032] Preparation Example 1-2 The preparation method of the polyether-modified aminosilicone is as follows: A1, under 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 into a reactor, the temperature was raised to 50°C, mixed and stirred for 10 min, the temperature was continuously raised to 100°C and 0.05 parts by weight of tetramethylammonium hydroxide was added, reacted for 4 h, after the reaction was completed, the temperature was raised to 140°C and reacted for another 15 min, after vacuum treatment for 2 h, hydrogen-containing aminosilicone oil was obtained; A2, in a reactor, 50 parts by weight of the hydrogen-containing amino silicone oil, 10 parts by weight of polyethylene glycol diacrylate and 20 parts by weight of isopropyl alcohol were added, the temperature was raised to 50°C, mixed and stirred for 10 min, then 0.1 parts by weight of 2% chloroplatinic acid-isopropyl alcohol solution was added and reacted for 20 min, and then polyether-modified amino polysiloxane was obtained by vacuum distillation.

[0033] Preparation Example 1-3 The preparation method of the polyether-modified amino polysiloxane is as follows: A1, under 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 in a reactor, the temperature was raised to 55°C, mixed and stirred for 20 min, then the temperature was raised to 105°C and 0.15 parts by weight of tetramethylammonium hydroxide was added, reacted for 6 h, after the reaction was completed, the temperature was raised to 150°C, and continued to react for 25 min, then vacuum treatment was carried out for 2 h to obtain a hydrogen-containing amino silicone oil; A2, in a reactor, 70 parts by weight of the hydrogen-containing amino silicone oil, 30 parts by weight of polyethylene glycol diacrylate and 40 parts by weight of isopropyl alcohol were added, the temperature was raised to 55°C, mixed and stirred for 20 min, then 0.5 parts by weight of 2% chloroplatinic acid-isopropyl alcohol solution was added and reacted for 40 min, and then polyether-modified amino polysiloxane was obtained by vacuum distillation.

[0034] Preparation Example 1-4 The preparation method of the polyether-modified amino polysiloxane is as follows: A1, under 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 in a reactor, the temperature was raised to 55°C, mixed and stirred for 15 min, then the temperature was raised to 105°C and 0.12 parts by weight of tetramethylammonium hydroxide was added, reacted for 5 h, after the reaction was completed, the temperature was raised to 145°C, and continued to react for 20 min, then vacuum treatment was carried out for 2 h to obtain a hydrogen-containing amino silicone oil; A2, in a reactor, 65 parts by weight of the hydrogen-containing amino silicone oil, 25 parts by weight of polyethylene glycol diacrylate and 35 parts by weight of isopropyl alcohol were added, the temperature was raised to 55°C, mixed and stirred for 15 min, then 0.35 parts by weight of 2% chloroplatinic acid-isopropyl alcohol solution was added and reacted for 30 min, and then polyether-modified amino polysiloxane was obtained by vacuum distillation.

[0035] Preparation Example 2-1 The preparation method of the water-based acrylic resin emulsion is as follows: B1, 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 were added into a reactor, mixed uniformly at room temperature, and then added into a solution composed of 120 parts by weight of water, 2 parts by weight of alkyl polyoxyethylene ether succinate monosulfonic acid disodium and 1.5 parts by weight of 3-allyloxy-2-hydroxypropane sulfonic acid sodium, emulsified by stirring to obtain pre-emulsified monomers; B2, 100 parts by weight of water, 0.8 parts by weight of alkyl polyoxyethylene ether succinate monosulfonic acid disodium, 0.5 parts by weight of 3-allyloxy-2-hydroxypropane sulfonic acid sodium and 0.2 parts by weight of ammonium persulfate were added into a reactor, heated to 75°C, 160 parts by weight of pre-emulsified monomers were added, and reacted for 30 min, then 2 parts by weight of 10% ammonium persulfate solution was added dropwise, reacted for 3 h after the addition was completed, cooled to room temperature, adjusted to pH 6.5 with ammonia water, and filtered with a 200-mesh sieve to obtain the aqueous acrylic resin emulsion.

[0036] Preparation Example 2-2 The preparation method of the aqueous acrylic resin emulsion is as follows: B1, 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 were added into a reactor, mixed uniformly at room temperature, and then added into a solution composed of 100 parts by weight of water, 1 part by weight of alkyl polyoxyethylene ether succinate monosulfonic acid disodium and 1 part by weight of 3-allyloxy-2-hydroxypropane sulfonic acid sodium, emulsified by stirring to obtain pre-emulsified monomers; B2, 80 parts by weight of water, 0.5 parts by weight of alkyl polyoxyethylene ether succinate monosulfonic acid disodium, 0.3 parts by weight of 3-allyloxy-2-hydroxypropane sulfonic acid sodium and 0.15 parts by weight of ammonium persulfate were added into a reactor, heated to 70°C, 150 parts by weight of pre-emulsified monomers were added, and reacted for 20 min, then 1.8 parts by weight of 10% ammonium persulfate solution was added dropwise, reacted for 2 h after the addition was completed, cooled to room temperature, adjusted to pH 6.5 with ammonia water, and filtered with a 200-mesh sieve to obtain the aqueous acrylic resin emulsion.

[0037] Preparation Example 2-3 The preparation method of the aqueous acrylic resin emulsion is as follows: B1, 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 were added into a reactor, mixed uniformly at room temperature, and then added into a solution composed of 150 parts by weight of water, 3 parts by weight of alkyl polyoxyethylene ether succinate monosulfonic acid disodium and 2 parts by weight of 3-allyloxy-2-hydroxypropane sulfonic acid sodium, emulsified by stirring to obtain pre-emulsified monomers; B2, add 120 parts by weight of water, 1.2 parts by weight of alkyl polyoxyethylene ether succinic acid monoester disodium sulfonate, 0.8 parts by weight of 3-allyloxy-2-hydroxypropane sulfonic acid sodium and 0.35 parts by weight of ammonium persulfate in the reactor, heat to 75℃, add 180 parts by weight of pre-emulsified monomers, keep reaction for 40 min, then add 3.2 parts by weight of 10% ammonium persulfate solution dropwise, keep reaction for 4h after the addition is completed, cool to room temperature, adjust pH to 6.5 with ammonia water, filter with a 200 mesh screen to obtain the water-based acrylic resin emulsion.

[0038] Preparation Example 2-4 The preparation method of the water-based 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 in the reactor, mix uniformly at room temperature, then add to a solution composed of 135 parts by weight of water, 2.5 parts by weight of alkyl polyoxyethylene ether succinic acid monoester disodium sulfonate and 1.8 parts by weight of 3-allyloxy-2-hydroxypropane sulfonic acid sodium, emulsify by stirring to obtain pre-emulsified monomers; B2, add 110 parts by weight of water, 1 part by weight of alkyl polyoxyethylene ether succinic acid monoester disodium sulfonate, 0.6 parts by weight of 3-allyloxy-2-hydroxypropane sulfonic acid sodium and 0.25 parts by weight of ammonium persulfate in the reactor, heat to 75℃, add 170 parts by weight of pre-emulsified monomers, keep reaction for 30 min, then add 2.5 parts by weight of 10% ammonium persulfate solution dropwise, keep reaction for 3h after the addition is completed, cool to room temperature, adjust pH to 6.5 with ammonia water, filter with a 200 mesh screen to obtain the water-based acrylic resin emulsion.

[0039] Example One 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 aminosilicone prepared in Preparation Example 1-1 to obtain a uniform 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 a speed of 1500 rpm for 20 min to form an oil-in-water emulsion, add 0.1 parts by weight of tetraethyl orthosilicate, increase the temperature to 50℃, reduce the stirring speed to 500 rpm and stir for 3h, then centrifuge, wash with deionized water for 3 times and dry at 40℃ for 4h to obtain self-healing capsules. S2, 10 parts by weight of calcium carbonate and 0.1 part by weight of sodium hexametaphosphate were added into 15 parts by weight of deionized water, and stirred at a speed of 2000 rpm for 20-40 min to obtain a calcium carbonate suspension; 6 parts by weight of rosin was heated to melt, 0.4 parts by weight of triethanolamine was added and stirred to obtain a mixture, which was added dropwise into 10 parts by weight of the calcium carbonate suspension, and the reaction temperature was controlled at 70°C, and the reaction was stirred for 2 h, after the reaction was completed, filtration was performed, deionized water was used for washing 3 times, and drying was performed at 40°C for 4 h to obtain rosin modified calcium carbonate, which was the inorganic filler; S3, 100 parts by weight of the water-based acrylic resin emulsion prepared in Preparation Example 2-1 was added into a reactor, 30 parts by weight of deionized water was added under stirring, the stirring speed was controlled at 400 r / min, and stirring was performed for 15 min, then 20 parts by weight of the inorganic filler was added, the stirring speed was increased to 700 r / min, and stirring was continued for 40 min, then 10 parts by weight of the self-healing capsule was added, the stirring speed was reduced to 400 r / min, and stirring was continued for 30 min, then 18 parts by weight of titanium white, 0.3 parts by weight of octanol and 0.5 parts by weight of dihydroxy trifluoro acrylate were added in sequence, the stirring speed was maintained at 400 r / min, and stirring was performed for 20 min, then hydroxyethyl cellulose was used to adjust the paint to a suitable viscosity, and a water-based paint was obtained.

[0040] Example Two Compared with Example One, the differences of the present example are as follows: 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 Example 1-2 were mixed to obtain a uniform oil phase; 10 parts by weight of the oil phase was added into 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 was added; In step S2, 10 parts by weight of calcium carbonate and 0.05 parts by weight of sodium hexametaphosphate were added into 10 parts by weight of deionized water to obtain a calcium carbonate suspension; 5 parts by weight of rosin was heated to melt, 0.2 parts by weight of triethanolamine was added and stirred to obtain a mixture, which was added dropwise into 8 parts by weight of the calcium carbonate suspension; In step S3, 100 parts by weight of the water-based acrylic resin emulsion prepared in Preparation Example 2-2 was added into a reactor, 20 parts by weight of deionized water was added under stirring, then 18 parts by weight of the inorganic filler was added, then 5 parts by weight of the self-healing capsule was added, and then 15 parts by weight of titanium white, 0.1 parts by weight of octanol and 0.2 parts by weight of dihydroxy trifluoro acrylate were added in sequence.

[0041] Example Three Compared with Example One, the differences of the present example are as follows: 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 aminopolysiloxane prepared in Preparation Example 1-3 were mixed to obtain a uniform oil phase; 10 parts by weight of the oil phase was 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 was added thereto; In step S2, 10 parts by weight of calcium carbonate and 0.12 parts by weight of sodium hexametaphosphate were added to 18 parts by weight of deionized water to obtain a calcium carbonate suspension; 8 parts by weight of rosin was heated to melt, 0.6 parts by weight of triethanolamine was added and stirred to obtain a mixture, which was added dropwise to 11 parts by weight of the calcium carbonate suspension; In step S3, 100 parts by weight of the aqueous acrylic resin emulsion prepared in Preparation Example 2-3 was added to a reactor, 40 parts by weight of deionized water was added under stirring, 22 parts by weight of inorganic filler was further added, 12 parts by weight of self-healing capsules was further added, and then 22 parts by weight of titanium dioxide, 0.4 parts by weight of octanol and 0.6 parts by weight of dihydroxy trifluoro acrylate were sequentially added.

[0042] Example Four Compared with Example One, the present example has the following differences: 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 aminopolysiloxane prepared in Preparation Example 1-3 were mixed to obtain a uniform oil phase; 10 parts by weight of the oil phase was 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 was added thereto; In step S2, 10 parts by weight of calcium carbonate and 0.12 parts by weight of sodium hexametaphosphate were added to 18 parts by weight of deionized water to obtain a calcium carbonate suspension; 8 parts by weight of rosin was heated to melt, 0.6 parts by weight of triethanolamine was added and stirred to obtain a mixture, which was added dropwise to 11 parts by weight of the calcium carbonate suspension; In step S3, 100 parts by weight of the aqueous acrylic resin emulsion prepared in Preparation Example 2-3 was added to a reactor, 40 parts by weight of deionized water was added under stirring, 22 parts by weight of inorganic filler was further added, 12 parts by weight of self-healing capsules was further added, and then 22 parts by weight of titanium dioxide, 0.4 parts by weight of octanol and 0.6 parts by weight of dihydroxy trifluoro acrylate were sequentially added.

[0043] Comparative Example One Compared with Example One, the present example has the following differences:

[0044] Comparative Example Two Comparative Example 2 is the same as Example 1 except that the aqueous acrylic resin emulsion prepared in Preparation Example 2-1 is replaced by a commercially available aqueous acrylic emulsion (BASF, Joncryl PRO 1552) in step S3.

[0045] Comparative Example 3 Comparative Example 3 is the same as Example 1 except that the polyether-modified aminopolysiloxane prepared in Preparation Example 1-1 is replaced by polysiloxane in step S1; and the aqueous acrylic resin emulsion prepared in Preparation Example 2-1 is replaced by a commercially available aqueous acrylic emulsion in step S3.

[0046] Comparative Example 4 Comparative Example 4 is the same as Example 1 except that the calcium carbonate is not modified and is directly used as the inorganic filler.

[0047] Comparative Example 5 Comparative Example 5 is the same as Example 1 except that the self-healing capsules are not added in the preparation process in step S3.

[0048] Comparative Example 6 Comparative Example 6 is the same as Example 1 except that the calcium carbonate is not modified and is directly used as the inorganic filler; the aqueous acrylic resin emulsion prepared in Preparation Example 2-1 is replaced by a commercially available aqueous acrylic emulsion in the preparation process in step S3; and the self-healing capsules are not added in the preparation process.

[0049] The aqueous paint prepared in Examples 1 to 4 and Comparative Examples 1 to 6 is subjected to relevant performance tests: Self-repairing performance test: the test result is shown in Table 1 according to the method specified in GB / T 1743-89.

[0050] Table 1 Self-repairing performance test result Adhesion test: the test result is shown in Table 2 according to the method specified in GB / T 9286-1998.

[0051] Hardness test: the test result is shown in Table 2 according to the method specified in GB / T 6739-2006.

[0052] Abrasion resistance test: the test result is shown in Table 2 according to the method specified in GB / T 1768-2006.

[0053] Table 2 Adhesion, hardness, and abrasion resistance test result It can be seen from the above test results that the aqueous paint prepared in the present application has good self-repairing performance, strong adhesion, and high abrasion resistance.

[0054] It is to be understood that the terminology used herein such as first and second, and the like, is only used to distinguish one entity or action from another entity or action, and does not necessarily require or imply any such actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0055] While the embodiments of the application have been shown and described herein, it is to be understood that the application is not limited to these embodiments and that various changes, modifications, substitutions and alterations can be made thereto without departing from the principles and spirit of the 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 in that: The following steps are involved: S100, preparing self-healing capsules using polyether-modified aminopolysiloxane and dry oil self-healing agent as raw materials; S200, preparing an inorganic filler using carboxyl-containing natural resin and inorganic carbonate raw materials; S300, mixing and stirring water-based acrylic resin emulsion, self-healing capsules, inorganic fillers, pigments and fillers, defoaming agents, and leveling agents to obtain the water-based paint.

2. The method for preparing an environmentally friendly water-based paint according to claim 1, characterized in that: 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 were added to a reactor, the temperature was raised to 50-55°C, mixed and stirred for 10-20 minutes, the temperature was further raised to 100-105°C and tetramethylammonium hydroxide was added, and the reaction was carried out for 4-6 hours. After the reaction was completed, the temperature was raised to 140-150°C, the reaction was continued for 15-25 minutes, and hydrogenated amino silicone oil was obtained after vacuum treatment; A2. Add hydrogenated amino silicone oil, polyethylene glycol diacrylate and isopropyl alcohol into the reactor, raise the temperature to 50-55°C, mix and stir for 10-20 minutes, then add chloroplatinic acid-isopropyl alcohol solution and react for 20-40 minutes, and obtain polyether-modified aminopolysiloxane by vacuum distillation.

3. The method for preparing an environmentally friendly water-based paint according to claim 1, characterized in that: Step S100 specifically includes: S110, mixing a drying oil self-healing agent and a polyether-modified aminopolysiloxane to obtain a uniform oil phase; S120, adding the oil phase to deionized water containing an emulsifier, high-speed shearing for 15-25 minutes to form an oil-in-water emulsion, adding a crosslinking agent thereto, raising the temperature to 45-55° C., reducing the stirring rate and stirring the reaction for 2-4 hours, and after the reaction is completed, centrifuging, washing, and drying to obtain the self-healing capsules.

4. The method for preparing an environmentally friendly water-based paint according to claim 1, characterized in that: The dry oil self-healing agent is one of linseed oil, tung oil, catalpa oil, perilla oil and hempseed oil, or a mixture of several of them.

5. The method for preparing an environmentally friendly water-based paint according to claim 1, characterized in that: Step S200 specifically includes: S210, adding calcium carbonate and a dispersant to deionized water, stirring at high speed for 20-40 minutes to obtain a calcium carbonate suspension; S220, heating rosin until it is melted, adding triethanolamine and stirring evenly to obtain a mixed solution, adding the mixed solution dropwise to the calcium carbonate suspension, controlling the reaction temperature to 60-80° C., stirring and reacting for 1-2 hours, and filtering, washing, and drying after the reaction to obtain rosin-modified calcium carbonate, which is the inorganic filler.

6. The method for preparing an environmentally friendly water-based paint according to claim 1, characterized in that: The preparation method of water-based acrylic resin emulsion is: B1. Add butyl acrylate, styrene, hydroxyethyl acrylate and (meth)acrylic acid into a reactor, mix them evenly at room temperature, and then add them to a solution consisting of water, disodium alkyl polyoxyethylene ether succinate monoester sulfonate and sodium 3-allyloxy-2-hydroxypropanesulfonate, and 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 into a reactor, heat to 70-75° C., add pre-emulsified monomer, keep warm and react for 20-40 minutes, then add ammonium persulfate solution, keep warm and react for 2-4 hours after the addition is completed, cool to room temperature, adjust the pH, and filter to obtain the aqueous acrylic resin emulsion.

7. The method for preparing an environmentally friendly water-based paint according to claim 1, characterized in that: Step S300 specifically includes: adding a water-based acrylic resin emulsion to a reactor, adding deionized water while stirring, controlling the speed at 300-400 r / min, stirring for 10-20 minutes, then adding an inorganic filler thereto, increasing the speed to 600-800 r / min, continuing to stir for 30-40 minutes, then adding a self-healing capsule thereto, reducing the speed to 300-400 r / min, continuing to stir for 20-30 minutes, then adding pigments, fillers, defoaming agents and leveling agents in sequence, maintaining the speed at 300-400 r / min, stirring for 15-25 minutes, and then adjusting the paint to a suitable viscosity to obtain the water-based paint.

8. An environmentally friendly water-based paint, characterized in that: The environmentally friendly water-based paint is prepared by the preparation method of any one of claims 1 to 7.

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