A reticle coating preventing normal temperature delamination and a preparation method thereof

Abstract

The application provides a temperature stratification preventing marking paint and a preparation method thereof, and belongs to the technical field of paints.The marking paint comprises the following raw materials in parts by weight: 1-2 parts of a temperature sensitive reversible crosslinking agent, 15-30 parts of an epoxy resin, 10-20 parts of an acrylic monomer, 1-2 parts of an emulsifier, 2-4 parts of temperature sensitive microcapsules, 0.5-1 part of nano titanium dioxide, 1-2 parts of inorganic asbestos fiber, 0.5-1.5 parts of high molecular fiber, 0.01-0.02 parts of an initiator, 3-4 parts of a water soluble epoxy curing agent, 2-3 parts of hollow glass microbeads, 2-4 parts of an additive, and 40-80 parts of water.The marking paint has temperature sensitive characteristics, is a weak gel network at normal temperature, inhibits filler settlement, hydrogen bonds are broken when construction is heated, the paint restores fluidity, crosslinking is recovered after temperature reduction, has relatively high strength and hardness, and the mechanical properties such as tensile strength, bending strength and hardness of the paint film are significantly improved, and the wear resistance and impact resistance are also enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of paint technology, in particular to a marking paint capable of preventing stratification at room temperature and a preparation method thereof. BACKGROUND

[0002] Traffic markings can provide the required information visually, which is conducive to guiding and controlling channelized traffic, ensuring safe and efficient operation of the entire traffic system, and protecting the safety of drivers and pedestrians. Currently, traffic marking paints can be mainly divided into hot melt type, solvent type, two-component and waterborne traffic marking paints. With the continuous enhancement of people's environmental awareness, the development of the traffic marking industry has entered a new period, and higher requirements have been put forward for traffic marking paints. On the basis of ensuring quality and performance, it is necessary to reduce the emission of volatile organic compounds (VOCs) and focus on green environmental protection.

[0003] Hot melt traffic marking paint needs to be continuously heated to 180-220℃ during use, which consumes a huge amount of energy; solvent type traffic marking paint is accompanied by a large amount of organic solvent volatilization during construction, which not only seriously endangers the health of construction personnel, but also causes serious pollution to the surrounding environment. Therefore, the traditional hot melt and solvent type traffic marking paints obviously do not meet the development needs. Waterborne traffic marking paint has obvious advantages over traditional solvent type and hot melt type paints due to its excellent practical performance and environmental protection performance as well as efficient construction performance.

[0004] According to the different base emulsions, waterborne traffic marking paints can be divided into waterborne acrylic, waterborne polyurethane, waterborne epoxy and waterborne alkyd traffic marking paints, etc. Waterborne acrylic-based paint has been widely used in the paint industry due to its good film-forming property, stability (including light, thermal and chemical stability), weather resistance, corrosion resistance and stain resistance, etc. In addition, acrylic emulsion is easy to modify. Environmentally friendly traffic marking paint represented by waterborne acrylic traffic marking paint has good durability in the whole life cycle, and is expected to replace solvent type and hot melt type traffic marking paints and become the mainstream development direction in the field of marking in the future.

[0005] In the formula of marking paint, a large amount of fillers are usually added to meet the performance in all directions. However, inorganic fillers added to organic resin systems often have problems such as easy precipitation, stratification and poor storage stability, which affect the construction operation and greatly limit the application of marking paint. SUMMARY

[0006] The present application aims to provide a marking paint capable of preventing stratification at normal temperature and a preparation method thereof, which has temperature-sensitive characteristics, is a weak gel network at normal temperature, inhibits filler settlement, breaks hydrogen bonds when heated for construction, restores the flowability of the paint, restores crosslinking after construction is completed, has high strength and hardness, and significantly improves the mechanical properties of the paint film, such as tensile strength, bending strength and hardness, and enhances the wear resistance and impact resistance of the paint, thus having a broad application prospect.

[0007] The technical scheme of the present application is implemented as follows:

[0008] The present application provides a marking paint capable of preventing stratification at normal temperature, which comprises the following raw materials in parts by weight: 1-2 parts of temperature-sensitive reversible crosslinking agent, 15-30 parts of epoxy resin, 10-20 parts of acrylic monomer, 1-2 parts of emulsifier, 2-4 parts of temperature-sensitive microcapsule, 0.5-1 part of nano-titanium dioxide, 1-2 parts of inorganic asbestos fiber, 0.5-1.5 parts of high molecular fiber, 0.01-0.02 parts of initiator, 3-4 parts of water-soluble epoxy curing agent, 2-3 parts of hollow glass microbead, 2-4 parts of additive, and 40-80 parts of water.

[0009] As a further improvement of the present application, the preparation method of the temperature-sensitive reversible crosslinking agent is as follows: polyvinyl alcohol is added into ethanol, boric acid and 1-hydroxyethyl-3-methyl imidazole chloride salt are added, stirring reaction is performed, and the solvent is removed under reduced pressure to obtain the temperature-sensitive reversible crosslinking agent.

[0010] As a further improvement of the present application, the mass ratio of the polyvinyl alcohol, boric acid and 1-hydroxyethyl-3-methyl imidazole chloride salt is 6-10:3-5:0.5-1.5, and the stirring reaction time is 2-4 h.

[0011] As a further improvement of the present application, the preparation method of the temperature-sensitive microcapsule is as follows:

[0012] S1. Preparation of branched polyester: pentaerythritol, catalyst are added into N,N-dimethylformamide, temperature is raised, stirring reaction is performed until the acid value is constant, the solvent is removed under reduced pressure, washing and drying are performed to obtain the branched polyester;

[0013] S2. Preparation of intercalated montmorillonite powder: montmorillonite powder is added into water, the branched polyester is added, stirring reaction is performed for intercalation, filtration, washing and drying are performed to obtain the intercalated montmorillonite powder;

[0014] S3. Preparation of modified fumed silica: fumed silica is added into Tris-HCl solution, tannic acid is added, heating and stirring reaction are performed, filtration, washing and drying are performed to obtain the modified fumed silica;

[0015] S4. Preparation of thixotropic agent: modified fumed silica and intercalated montmorillonite powder are added to water, stirred and reacted, filtered, washed, dried, and the thixotropic agent is prepared;

[0016] S5. Preparation of temperature-sensitive microcapsules: glycerol monostearate is dissolved in ethanol, konjac gum is added, heated and stirred to mix uniformly to obtain an ethanol phase; the thixotropic agent and emulsifier are added to water, stirred and mixed uniformly to obtain an aqueous phase, which is added dropwise to the ethanol phase, stirred and mixed, placed in an ice water bath, filtered, washed, dried, and the temperature-sensitive microcapsules are prepared.

[0017] As a further improvement of the present application, the molar ratio of trimellitic anhydride, trimethylolpropane, and catalyst in step S1 is 2-4:1:0.1-0.15, the catalyst is p-toluenesulfonic acid, and the temperature of the heated and stirred reaction is 120-140℃; in step S2, the mass ratio of montmorillonite powder and branched polyester is 10:1.5-2.5, and the temperature of the stirred and intercalated reaction is 35-45℃ for 0.5-1.5h.

[0018] As a further improvement of the present application, in step S3, the pH value of the Tris-HCl solution is 8.5-9.5, the mass ratio of fumed silica and tannic acid is 8-10:2-3, the temperature of the heated and stirred reaction is 40-50℃ for 3-5h; in step S4, the mass ratio of modified fumed silica and intercalated montmorillonite powder is 3-5:6-8; in step S5, the mass ratio of glycerol monostearate, konjac gum, thixotropic agent, and emulsifier is 6-8:2-4:3-5:0.5-1, the emulsifier is selected from at least one of Tween-20, Tween-40, Tween-60, Tween-80, and Tween-85, and the heating temperature is 40-50℃.

[0019] As a further improvement of the present application, the acrylic monomer includes methyl methacrylate, butyl acrylate, acrylamide, styrene, and 1-allyl-3-methyl imidazole tetrafluoroborate, and the mass ratio is 3-5:4-6:2-4:1-2:2-4.

[0020] The introduction of the rigid styrene monomer with benzene ring structure in the monomer can obviously improve the hardness and mechanical strength of the coating, meanwhile, the introduction of 1-allyl-3-methyl imidazole tetrafluoroborate can improve the thermal stability of the coating, reduce the occurrence of thermal degradation, meanwhile, improve the flame retardant performance and antibacterial performance, enhance the chemical corrosion resistance, the 1-allyl-3-methyl imidazole tetrafluoroborate monomer contains active double bond and imidazole ring structure, and can be crosslinked with other monomers or polypropylene resin molecular chain under appropriate conditions. The double bond in the molecule can be copolymerized or grafted with the unsaturated group in the polypropylene resin, and the active hydrogen on the imidazole ring can also be crosslinked and cured with some compounds containing active groups, so that a three-dimensional crosslinked network structure is formed, and the crosslinking density and performance of the material are improved.

[0021] As a further improvement of the present application, the high molecular fiber is selected from at least one of polyester fiber, polyethylene fiber, polypropylene fiber and nylon fiber; the emulsifier is selected from at least one of Tween-20, Tween-40, Tween-60, Tween-80 and Tween-85; the initiator is selected from at least one of sodium persulfate, potassium persulfate and ammonium persulfate; the hollow glass microbead comprises hollow glass microbeads with an average particle size of 40-50 microns and hollow glass microbeads with an average particle size of 100-150 microns, and the mass ratio is 3-5:7-10.

[0022] The hollow glass microbeads with different particle sizes are selected to form a density gradient buffer layer with the resin base material, so that the sedimentation path of the inorganic matter is blocked, and the storage period is prolonged.

[0023] The present application further protects a preparation method of the above-mentioned reticle coating capable of preventing normal temperature delamination, comprising the following steps:

[0024] (1) uniformly mix water and an emulsifier to prepare a pre-emulsion;

[0025] (2) add epoxy resin and acrylic monomer to the pre-emulsion and uniformly stir and mix to prepare an emulsion;

[0026] (3) add temperature-sensitive microcapsules, nano-titanium dioxide, hollow glass microbeads, inorganic asbestos fibers, high molecular fibers to the emulsion and uniformly stir and mix, add an initiator and a water-soluble epoxy curing agent, heat and stir to react, add a temperature-sensitive reversible crosslinking agent and an additive, uniformly stir and mix to prepare the reticle coating capable of preventing normal temperature delamination.

[0027] The present application has the following beneficial effects:

[0028] The application prepares a temperature-sensitive reversible crosslinking agent, which is mainly borate ester bond formed by crosslinking polyvinyl alcohol and boric acid, and is a dynamic reversible covalent bond. Under heating condition, the borate ester bond will be broken due to sufficient energy, so that the crosslinking structure is disintegrated, and the polyvinyl alcohol restores fluidity. The application also adds 1-hydroxyethyl-3-methyl imidazole chloride with hydroxyl structure, which can increase the flexibility and fluidity of polyvinyl alcohol molecular chain, so that the borate ester bond is more easily broken when heated, and the reversibility of crosslinking is promoted. By adding the temperature-sensitive reversible crosslinking agent, the coating forms a weak gel network at room temperature (<25℃), and the filler settlement is inhibited; when heated (>60℃), the hydrogen bond is broken, the coating restores fluidity, and after coating, it is cooled and re-crosslinked, so that the required coating is prepared.

[0029] The application further prepares a temperature-sensitive microcapsule, which takes a thixotropic agent as core material and a temperature-sensitive polymer as shell layer. Glycerol monostearate is used as the wall material of the microcapsule to protect the core material, but the microcapsule with glycerol monostearate as the wall material has problems such as low encapsulation rate and easy leakage of the core material when encountering water. The main component of konjac gum is konjac glucomannan, which has strong gelation and film formation, and is conducive to improving the encapsulation rate and stability of the microcapsule. The prepared capsule is complete at room temperature, and the thixotropic agent is not released; when heated, the shell layer softens, and the thixotropic agent is slowly released into the system. In the process of high-speed stirring, it quickly changes into a low-viscosity fluid under the action of shear force (stirring, brushing, etc.), to ensure the smoothness of construction, and restores to a high-viscosity state after the external force is removed, so as to balance the storage stability and construction performance.

[0030] In the preparation process of the thixotropic agent, the branched polyester intercalated montmorillonite is first prepared. When the intercalated montmorillonite is fully dispersed in the organic resin system, the intercalated montmorillonite layers are easily bridged by hydrogen bonds, forming a thixotropic gel body with a card layer house structure, thereby improving the viscosity, thixotropy, film formation and other properties of the material. At the same time, the branched polyester not only can separate the interlayer distance of the montmorillonite and improve the thixotropy, but also can support and wrap the filler particles with the network structure, so that the filler particles are difficult to aggregate and settle. A large number of active functional groups such as carboxyl groups can react with active groups in the polyacrylic acid resin to form a chemically bonded crosslinked network structure, promote the curing reaction process of the coating, improve the crosslinking density and performance of the coating, and the branched polyester also has good compatibility with the polyacrylic acid resin, thereby improving the dispersibility of the material.

[0031] In addition, the montmorillonite intercalated by the branched polyester itself has high strength and hardness. Through the crosslinking reaction with the polyacrylic acid resin, the mechanical properties of the branched polyester are transferred to the coating system, so that the tensile strength, bending strength and hardness and other mechanical properties of the paint film are significantly improved, thereby enhancing the wear resistance and impact resistance of the coating.

[0032] The surface of fumed silica usually contains a small amount of silanol groups. When the particles are close to each other, hydrogen bonds are easily formed between the hydroxyl groups on the silanol, so that the particles are connected to each other through weak bond interaction, thereby further forming a three-dimensional network structure. This three-dimensional network structure hinders the movement of other substances in the system, thereby increasing the viscosity of the system, and thus having thixotropy. After the surface tannic acid is modified by polymerization, on the one hand, it can be well bonded with intercalated montmorillonite powder, thereby preparing a composite thixotropic agent, and on the other hand, the structure of tannic acid can also play a similar function of branched polyester, thereby improving the crosslinking property, mechanical property and preventing precipitation of the coating, etc.

[0033] The marking paint prepared by the present application has temperature-sensitive properties. At room temperature, it is a weak gel network, which inhibits the settling of fillers. When heated during construction, the hydrogen bonds are broken, the paint restores fluidity, and after the construction is completed, it restores crosslinking, has high strength and hardness, and significantly improves the mechanical properties such as tensile strength, bending strength and hardness of the paint film, also enhances the wear resistance and impact resistance of the paint, and has a broad application prospect. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be clearly and completely described below. 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.

[0035] Preparation of temperature-sensitive reversible crosslinking agent

[0036] The method is as follows: 6g of polyvinyl alcohol is added to ethanol, 3g of boric acid and 0.5g of 1-hydroxyethyl-3-methyl imidazole chloride salt are added, stirring is carried out for 2h, and the solvent is removed under reduced pressure to prepare the temperature-sensitive reversible crosslinking agent.

[0037] Preparation of temperature-sensitive reversible crosslinking agent

[0038] The method is as follows: 10g of polyvinyl alcohol is added to ethanol, 5g of boric acid and 1.5g of 1-hydroxyethyl-3-methyl imidazole chloride salt are added, stirring is carried out for 4h, and the solvent is removed under reduced pressure to prepare the temperature-sensitive reversible crosslinking agent.

[0039] Preparation of temperature-sensitive reversible crosslinking agent

[0040] The method is as follows: 8g of polyvinyl alcohol is added to ethanol, 4g of boric acid and 1g of 1-hydroxyethyl-3-methyl imidazole chloride salt are added, stirring is carried out for 3h, and the solvent is removed under reduced pressure to prepare the temperature-sensitive reversible crosslinking agent.

[0041] Comparative Preparation Example 1

[0042] The difference compared with Preparation Example 3 is that 1-hydroxyethyl-3-methyl imidazole chloride salt is not added.

[0043] The method is as follows: 9 g of polyvinyl alcohol is added into ethanol, 4 g of boric acid is added, stirring is carried out for 3 h, and the solvent is removed under reduced pressure to prepare the temperature-sensitive reversible crosslinking agent.

[0044] Preparation of temperature-sensitive microcapsules

[0045] The method is as follows:

[0046] S1. Preparation of branched polyester: 0.2 mol of trimellitic anhydride, 0.1 mol of trimethylolpropane and 0.01 mol of p-toluenesulfonic acid are added into 200 mL of N,N-dimethylformamide, the temperature is raised to 120°C, stirring is carried out until the acid value is constant, the solvent is removed under reduced pressure, washing is carried out, and drying is carried out to prepare the branched polyester;

[0047] S2. Preparation of intercalated montmorillonite powder: 10 g of montmorillonite powder is added into 200 mL of water, 1.5 g of the branched polyester is added, stirring is carried out at 35°C for 0.5 h of intercalation, filtration is carried out, washing is carried out, and drying is carried out to prepare the intercalated montmorillonite powder;

[0048] S3. Preparation of modified fumed silica: 8 g of fumed silica is added into 150 mL of Tris-HCl solution with a pH value of 8.5, 2 g of tannic acid is added, heating is carried out to 40°C, stirring is carried out for 3 h, filtration is carried out, washing is carried out, and drying is carried out to prepare the modified fumed silica;

[0049] S4. Preparation of thixotropic agent: 3 g of the modified fumed silica and 6 g of the intercalated montmorillonite powder are added into 150 mL of water, stirring is carried out for 30 min, filtration is carried out, washing is carried out, and drying is carried out to prepare the thixotropic agent;

[0050] S5. Preparation of temperature-sensitive microcapsules: 6 g of glyceryl monostearate is dissolved in 200 mL of ethanol, 2 g of konjac gum is added, heating is carried out to 40°C, and stirring is carried out until the mixture is uniform to obtain an ethanol phase; 3 g of the thixotropic agent and 0.5 g of Tween-85 are added into 100 mL of water, stirring is carried out until the mixture is uniform to obtain an aqueous phase, the aqueous phase is added dropwise into the ethanol phase, stirring is carried out for 30 min, an ice water bath is used, filtration is carried out, washing is carried out, and drying is carried out to prepare the temperature-sensitive microcapsules.

[0051] Preparation of temperature-sensitive microcapsules

[0052] The method is as follows:

[0053] S1. Preparation of branched polyester: 0.4 mol of trimellitic anhydride, 0.1 mol of trimethylolpropane and 0.015 mol of p-toluenesulfonic acid are added into 200 mL of N,N-dimethylformamide, the temperature is raised to 140°C, stirring is carried out until the acid value is constant, the solvent is removed under reduced pressure, washing is carried out, and drying is carried out to prepare the branched polyester;

[0054] S2. Preparation of intercalated montmorillonite powder: 10 g of montmorillonite powder was added to 200 mL of water, 2.5 g of branched polyester was added, and the reaction was intercalated by stirring at 45°C for 1.5 h, filtered, washed, and dried to obtain the intercalated montmorillonite powder;

[0055] S3. Preparation of modified fumed silica: 10 g of fumed silica was added to 150 mL of Tris-HCl solution with a pH value of 9.5, 3 g of tannic acid was added, heated to 50°C, and stirred for 5 h, filtered, washed, and dried to obtain the modified fumed silica;

[0056] S4. Preparation of thixotropic agent: 5 g of modified fumed silica and 8 g of intercalated montmorillonite powder were added to 150 mL of water, stirred for 30 min, filtered, washed, and dried to obtain the thixotropic agent;

[0057] S5. Preparation of temperature-sensitive microcapsules: 8 g of glyceryl monostearate was dissolved in 200 mL of ethanol, 4 g of konjac gum was added, heated to 50°C, and stirred to mix uniformly to obtain an ethanol phase; 5 g of thixotropic agent and 1 g of Tween-60 were added to 100 mL of water, stirred to mix uniformly to obtain an aqueous phase, the aqueous phase was added dropwise to the ethanol phase, stirred for 30 min, placed in an ice water bath, filtered, washed, and dried to obtain the temperature-sensitive microcapsules.

[0058] Preparation of temperature-sensitive microcapsules

[0059] The method is as follows:

[0060] S1. Preparation of branched polyester: 0.3 mol of trimellitic anhydride, 0.1 mol of trimethylolpropane, and 0.012 mol of p-toluenesulfonic acid were added to 200 mL of N,N-dimethylformamide, heated to 130°C, and stirred until the acid value was constant, the solvent was removed under reduced pressure, washed, and dried to obtain the branched polyester;

[0061] S2. Preparation of intercalated montmorillonite powder: 10 g of montmorillonite powder was added to 200 mL of water, 2 g of branched polyester was added, and the reaction was intercalated by stirring at 40°C for 1 h, filtered, washed, and dried to obtain the intercalated montmorillonite powder;

[0062] S3. Preparation of modified fumed silica: 9 g of fumed silica was added to 150 mL of Tris-HCl solution with a pH value of 9, 2.5 g of tannic acid was added, heated to 45°C, and stirred for 4 h, filtered, washed, and dried to obtain the modified fumed silica;

[0063] S4. Preparation of thixotropic agent: 4 g of modified fumed silica and 7 g of intercalated montmorillonite powder were added to 150 mL of water, stirred for 30 min, filtered, washed, and dried to obtain the thixotropic agent;

[0064] S5. Preparation of temperature-sensitive microcapsules: 7 g of glycerol monostearate was dissolved in 200 mL of ethanol, 3 g of konjac gum was added, heated to 45°C, stirred and mixed uniformly to obtain an ethanol phase; 4 g of thixotropic agent and 0.7 g of Tween-80 were added to 100 mL of water, stirred and mixed uniformly to obtain an aqueous phase, the aqueous phase was added dropwise to the ethanol phase, stirred and mixed for 30 min, placed in an ice water bath, filtered, washed, and dried to obtain temperature-sensitive microcapsules.

[0065] Comparative Preparation Example 2

[0066] Compared with Preparation Example 6, the difference is that steps S1 and S2 are not performed.

[0067] Specifically as follows:

[0068] S1. Preparation of modified fumed silica: 9 g of fumed silica was added to 150 mL of Tris-HCl solution with a pH value of 9, 2.5 g of tannic acid was added, heated to 45°C, stirred and reacted for 4 h, filtered, washed, and dried to obtain modified fumed silica;

[0069] S2. Preparation of thixotropic agent: 4 g of modified fumed silica and 7 g of montmorillonite powder were added to 150 mL of water, stirred and reacted for 30 min, filtered, washed, and dried to obtain thixotropic agent;

[0070] S3. Preparation of temperature-sensitive microcapsules: 7 g of glycerol monostearate was dissolved in 200 mL of ethanol, 3 g of konjac gum was added, heated to 45°C, stirred and mixed uniformly to obtain an ethanol phase; 4 g of thixotropic agent and 0.7 g of Tween-80 were added to 100 mL of water, stirred and mixed uniformly to obtain an aqueous phase, the aqueous phase was added dropwise to the ethanol phase, stirred and mixed for 30 min, placed in an ice water bath, filtered, washed, and dried to obtain temperature-sensitive microcapsules.

[0071] Comparative Preparation Example 3

[0072] Compared with Preparation Example 6, the difference is that step S3 is not performed.

[0073] Specifically as follows:

[0074] S1. Preparation of branched polyester: 0.3 mol of trimellitic anhydride, 0.1 mol of trimethylolpropane, and 0.012 mol of p-toluenesulfonic acid were added to 200 mL of N,N-dimethylformamide, heated to 130°C, and stirred and reacted until the acid value was constant, the solvent was removed under reduced pressure, washed, and dried to obtain branched polyester;

[0075] S2. Preparation of intercalated montmorillonite powder: 10 g of montmorillonite powder was added to 200 mL of water, 2 g of branched polyester was added, and stirred and reacted for intercalation at 40°C for 1 h, filtered, washed, and dried to obtain intercalated montmorillonite powder;

[0076] S3. Preparation of the thixotropic agent: 4 g of fumed silica and 7 g of intercalated montmorillonite powder were added to 150 mL of water, stirred for 30 min, filtered, washed, and dried to obtain the thixotropic agent;

[0077] S4. Preparation of the temperature-sensitive microcapsule: 7 g of glyceryl monostearate was dissolved in 200 mL of ethanol, 3 g of konjac gum was added, heated to 45 °C, and stirred to obtain an ethanol phase; 4 g of the thixotropic agent and 0.7 g of Tween-80 were added to 100 mL of water, stirred to obtain an aqueous phase, and the aqueous phase was added dropwise to the ethanol phase, stirred for 30 min, placed in an ice water bath, filtered, washed, and dried to obtain the temperature-sensitive microcapsule.

[0078] Comparative Preparation Example 4

[0079] Compared with Preparation Example 6, the difference is that no modified fumed silica is added in step S4.

[0080] Specifically as follows:

[0081] S1. Preparation of the branched polyester: 0.3 mol of trimellitic anhydride, 0.1 mol of trimethylolpropane, and 0.012 mol of p-toluenesulfonic acid were added to 200 mL of N,N-dimethylformamide, heated to 130 °C, and stirred until the acid value was constant, then the solvent was removed under reduced pressure, washed, and dried to obtain the branched polyester;

[0082] S2. Preparation of the intercalated montmorillonite powder: 10 g of montmorillonite powder was added to 200 mL of water, 2 g of the branched polyester was added, and stirred at 40 °C for 1 h to intercalate, then filtered, washed, and dried to obtain the intercalated montmorillonite powder, which is the thixotropic agent;

[0083] S3. Preparation of the temperature-sensitive microcapsule: 7 g of glyceryl monostearate was dissolved in 200 mL of ethanol, 3 g of konjac gum was added, heated to 45 °C, and stirred to obtain an ethanol phase; 4 g of the thixotropic agent and 0.7 g of Tween-80 were added to 100 mL of water, stirred to obtain an aqueous phase, and the aqueous phase was added dropwise to the ethanol phase, stirred for 30 min, placed in an ice water bath, filtered, washed, and dried to obtain the temperature-sensitive microcapsule.

[0084] Comparative Preparation Example 5

[0085] Compared with Preparation Example 6, the difference is that no intercalated montmorillonite powder is added in step S4.

[0086] Specifically as follows:

[0087] S1. Preparation of modified fumed silica: 9 g of fumed silica was added to 150 mL of Tris-HCl solution with pH value of 9, 2.5 g of tannic acid was added, heated to 45℃, stirred for 4 h, filtered, washed, dried, and modified fumed silica was prepared, which was a thixotropic agent;

[0088] S2. Preparation of temperature-sensitive microcapsules: 7 g of glyceryl monostearate was dissolved in 200 mL of ethanol, 3 g of konjac gum was added, heated to 45℃, stirred and mixed uniformly to obtain an ethanol phase; 4 g of thixotropic agent and 0.7 g of Tween-80 were added to 100 mL of water, stirred and mixed uniformly to obtain an aqueous phase, the aqueous phase was added dropwise to the ethanol phase, stirred and mixed for 30 min, placed in an ice water bath, filtered, washed, and dried to prepare temperature-sensitive microcapsules.

[0089] Comparative Preparation Example 6

[0090] Compared with Preparation Example 6, the difference is that step S5 is not performed.

[0091] The specific process is as follows:

[0092] S1. Preparation of branched polyester: 0.3 mol of trimellitic anhydride, 0.1 mol of trimethylolpropane, and 0.012 mol of p-toluenesulfonic acid were added to 200 mL of N,N-dimethylformamide, heated to 130℃, and stirred until the acid value was constant, then the solvent was removed under reduced pressure, washed, and dried to prepare branched polyester;

[0093] S2. Preparation of intercalated montmorillonite powder: 10 g of montmorillonite powder was added to 200 mL of water, 2 g of branched polyester was added, and stirred at 40℃ for 1 h to intercalate, then filtered, washed, and dried to prepare intercalated montmorillonite powder;

[0094] S3. Preparation of modified fumed silica: 9 g of fumed silica was added to 150 mL of Tris-HCl solution with pH value of 9, 2.5 g of tannic acid was added, heated to 45℃, stirred for 4 h, filtered, washed, dried, and modified fumed silica was prepared;

[0095] S4. Preparation of thixotropic agent: 4 g of modified fumed silica and 7 g of intercalated montmorillonite powder were added to 150 mL of water, stirred for 30 min, filtered, washed, and dried to prepare thixotropic agent.

[0096] Example 1

[0097] This example provides a reticle coating capable of preventing delamination at room temperature.

[0098] Raw material composition (parts by weight): temperature-sensitive reversible crosslinking agent 1 part prepared in Preparation Example 1, epoxy resin (NPEL 128, Nanya Resin) 15 parts, acrylic monomer 10 parts, emulsifier 1 part, temperature-sensitive microcapsule 2 parts prepared in Preparation Example 4, nano-titanium dioxide 0.5 part, inorganic asbestos fiber 1 part, polyester fiber 0.5 part, ammonium persulfate 0.01 part, water-soluble epoxy curing agent (BANCO 901, BANG & CHEMICAL (CHINA) CO., LTD.) 3 parts, hollow glass microbead 2 parts, auxiliary agent 2 parts, water 40 parts. The auxiliary agent includes dipropylene glycol butyl ether, dispersant (BYK-190, BYK CHEMICAL), defoaming agent (TEGO Airex 902W, DEGUSSA DICO), 2-amino-2-methyl-1-propanol, mass ratio of 1:0.2:0.1:0.5. The acrylic monomer includes methyl methacrylate, butyl acrylate, acrylamide, styrene and 1-allyl-3-methyl imidazole tetrafluoroborate, mass ratio of 3:4:2:1:2.

[0099] The preparation method includes the following steps:

[0100] (1) Mix water and emulsifier, stir and mix at 800 r / min for 20 min to prepare a pre-emulsion;

[0101] (2) Add epoxy resin and acrylic monomer to the pre-emulsion, stir and mix at 800 r / min for 30 min to prepare an emulsion;

[0102] (3) Add temperature-sensitive microcapsule, nano-titanium dioxide, hollow glass microbead, inorganic asbestos fiber and polyester fiber to the emulsion, stir and mix at 800 r / min for 20 min, add ammonium persulfate and water-soluble epoxy curing agent, heat to 60℃, continue to stir and react for 2 h, add temperature-sensitive reversible crosslinking agent and auxiliary agent, continue to stir and react for 1 h at constant temperature to prepare the temperature-sensitive reversible crosslinking agent.

[0103] Example 2

[0104] The present embodiment provides a temperature-sensitive reversible crosslinking agent for preventing temperature stratification.

[0105] Raw material composition (parts by weight): temperature-sensitive reversible crosslinking agent 2 parts prepared in Preparation Example 2, epoxy resin (NPEL 128, Nan Ya Resin) 30 parts, acrylic monomer 20 parts, emulsifier 2 parts, temperature-sensitive microcapsule 4 parts prepared in Preparation Example 5, nano-titanium dioxide 1 part, inorganic asbestos fiber 2 parts, polypropylene fiber 1.5 parts, potassium persulfate 0.02 parts, water-soluble epoxy curing agent (BANCO 901, BANGCHEM (CHINA) CO., LTD.) 4 parts, hollow glass microbead 3 parts, auxiliary agent 4 parts, and water 80 parts. The auxiliary agent includes dipropylene glycol butyl ether, dispersant (BYK-190, BYK CHEMICAL), defoaming agent (TEGO Airex 902W, DEGUSSA DICO), 2-amino-2-methyl-1-propanol, and the mass ratio is 1:0.2:0.1:0.5. The acrylic monomer includes methyl methacrylate, butyl acrylate, acrylamide, styrene, and 1-allyl-3-methylimidazolium tetrafluoroborate, and the mass ratio is 5:6:4:2:4.

[0106] The preparation method includes the following steps:

[0107] (1) Mix water and emulsifier, and stir and mix at 800 r / min for 20 min to prepare a pre-emulsion;

[0108] (2) Add epoxy resin and acrylic monomer to the pre-emulsion, and stir and mix at 800 r / min for 30 min to prepare an emulsion;

[0109] (3) Add temperature-sensitive microcapsule, nano-titanium dioxide, hollow glass microbead, inorganic asbestos fiber, and polypropylene fiber to the emulsion, and stir and mix at 800 r / min for 20 min, add potassium persulfate and water-soluble epoxy curing agent, heat to 80℃, continue to stir and react for 3 h, add temperature-sensitive reversible crosslinking agent and auxiliary agent, and continue to stir and react for 3 h at constant temperature to prepare the marking paint capable of preventing stratification at room temperature.

[0110] Example 3

[0111] The present embodiment provides a marking paint capable of preventing stratification at room temperature.

[0112] Raw material composition (parts by weight): 1.5 parts of temperature-sensitive reversible crosslinking agent prepared in Preparation Example 3, 22 parts of epoxy resin (NPEL 128, Nanya Resin), 15 parts of acrylic monomer, 1.5 parts of emulsifier, 3 parts of temperature-sensitive microcapsule prepared in Preparation Example 6, 0.7 parts of nano-titanium dioxide, 1.5 parts of inorganic asbestos fiber, 1 part of polyester fiber, 0.015 parts of sodium persulfate, 3.5 parts of water-soluble epoxy curing agent (BANCO 901, BANCO (China) Co., Ltd.), 2.5 parts of hollow glass microbead, 3 parts of auxiliary agent, and 60 parts of water. The auxiliary agent includes dipropylene glycol butyl ether, dispersant (BYK-190, BYK-Chemie), defoaming agent (TEGO Airex 902W, Evonik), 2-amino-2-methyl-1-propanol, and the mass ratio is 1:0.2:0.1:0.5. The acrylic monomer includes methyl methacrylate, butyl acrylate, acrylamide, styrene, and 1-allyl-3-methylimidazolium tetrafluoroborate, and the mass ratio is 4:5:3:1.5:3.

[0113] The preparation method includes the following steps:

[0114] (1) Mix water and emulsifier, and stir and mix at 800 r / min for 20 min to prepare a pre-emulsion;

[0115] (2) Add epoxy resin and acrylic monomer to the pre-emulsion, and stir and mix at 800 r / min for 30 min to prepare an emulsion;

[0116] (3) Add temperature-sensitive microcapsule, nano-titanium dioxide, hollow glass microbead, inorganic asbestos fiber, and polyester fiber to the emulsion, and stir and mix at 800 r / min for 20 min. Add sodium persulfate and water-soluble epoxy curing agent, heat to 70°C, and continue to stir and react for 2.5 h. Add temperature-sensitive reversible crosslinking agent and auxiliary agent, and continue to stir and react for 2 h to prepare a mark coating capable of preventing stratification at room temperature.

[0117] Comparative Example 1

[0118] Compared with Example 3, the difference is that the temperature-sensitive reversible crosslinking agent is prepared in Comparative Preparation Example 1.

[0119] Comparative Example 2

[0120] Compared with Example 3, the difference is that the temperature-sensitive reversible crosslinking agent is not added.

[0121] Comparative Example 3

[0122] Compared with Example 3, the difference is that the temperature-sensitive microcapsule is prepared in Comparative Preparation Example 2.

[0123] Comparative Example 4

[0124] The difference compared with Example 3 is that the temperature-sensitive microcapsules are prepared from Comparative Preparation Example 3.

[0125] Comparative Example 5

[0126] The difference compared with Example 3 is that the temperature-sensitive microcapsules are prepared from Comparative Preparation Example 4.

[0127] Comparative Example 6

[0128] The difference compared with Example 3 is that the temperature-sensitive microcapsules are prepared from Comparative Preparation Example 5.

[0129] Comparative Example 7

[0130] The difference compared with Example 3 is that the temperature-sensitive microcapsules are replaced by thixotropic agents prepared from Comparative Preparation Example 6.

[0131] Comparative Example 8

[0132] The difference compared with Example 3 is that no temperature-sensitive microcapsules are added.

[0133] Comparative Example 9

[0134] The difference compared with Example 3 is that 1-allyl-3-methylimidazolium tetrafluoroborate is not added in the acrylic monomer. The acrylic monomer includes methyl methacrylate, butyl acrylate, acrylamide and styrene, and the mass ratio is 4:5:3:1.5.

[0135] Comparative Example 10

[0136] The difference compared with Example 3 is that styrene is not added in the acrylic monomer. The acrylic monomer includes methyl methacrylate, butyl acrylate, acrylamide and 1-allyl-3-methylimidazolium tetrafluoroborate, and the mass ratio is 4:5:3:3.

[0137] Test Example 1

[0138] The reticle coatings prepared in Examples 1-3 and Comparative Examples 1-10 are tested for performance, and the results are shown in Table 1.

[0139] The adhesion is detected according to the method of GB / T 9286-2021;

[0140] The pencil hardness is detected according to the method of GB / T 6739-2022;

[0141] The water resistance is detected according to the method of GB / T 1733-1993;

[0142] The wear resistance is detected according to the method of GB / T 1768-2006;

[0143] The detection method of the compressive strength is as follows: 3 pieces of 20mm*20mm*20mm paint compression test blocks are cast, and the compression test is carried out after being placed at room temperature for 24 hours; the precision of the electronic universal material testing machine is not less than 0.5 level, the pre-load is 10N, the loading speed is 30mm / min, and the compressive strength of the paint is tested.

[0144] Table 1

[0145]

[0146]

[0147] It can be seen from the above table that the reticle paint prepared by examples 1-3 of the present application has good comprehensive performance for preventing stratification at room temperature.

[0148] Test Example 2

[0149] The reticle paint prepared by examples 1-3 and comparative examples 1-10 for preventing stratification at room temperature is placed at room temperature for 6 months and 12 months, and the precipitation change is observed, and the results are shown in Table 2.

[0150] Table 2

[0151]

[0152]

[0153] It can be seen from the above table that the reticle paint prepared by examples 1-3 of the present application will not produce precipitation after being placed at room temperature for 12 months or more, and has good storage performance.

[0154] The above only describes the preferred embodiments of the present application, and is not used to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A reticle coating for preventing ambient temperature delamination, characterized by, The raw materials include the following weight parts: 1-2 parts of temperature-sensitive reversible crosslinking agent, 15-30 parts of epoxy resin, 10-20 parts of acrylic monomer, 1-2 parts of emulsifier, 2-4 parts of temperature-sensitive microcapsule, 0.5-1 part of nano titanium dioxide, 1-2 parts of inorganic asbestos fiber, 0.5-1.5 parts of high molecular fiber, 0.01-0.02 parts of initiator, 3-4 parts of water-soluble epoxy curing agent, 2-3 parts of hollow glass microbead, 2-4 parts of auxiliary agent, and 40-80 parts of water; the preparation method of the temperature-sensitive reversible crosslinking agent is as follows: polyvinyl alcohol is added into ethanol, boric acid and 1-hydroxyethyl-3-methyl imidazole chloride salt are added, stirring reaction is conducted, and the solvent is removed under reduced pressure to obtain the temperature-sensitive reversible crosslinking agent; The preparation method of the temperature-sensitive microcapsule is as follows: S1. Preparation of branched polyester: trimellitic anhydride, trimethylolpropane and catalyst are added into N,N-dimethylformamide, temperature is raised for stirring reaction until the acid value is constant, the solvent is removed under reduced pressure, and then washing, drying are conducted to obtain the branched polyester; S2. Preparation of intercalated montmorillonite powder: montmorillonite powder is added into water, and then the branched polyester is added for stirring reaction intercalation, filtration, washing and drying to obtain the intercalated montmorillonite powder; S3. Preparation of modified fumed silica: fumed silica is added into Tris-HCl solution, and then tannic acid is added for heating stirring reaction, filtration, washing and drying to obtain the modified fumed silica; S4. Preparation of thixotropic agent: the modified fumed silica and the intercalated montmorillonite powder are added into water for stirring reaction, filtration, washing and drying to obtain the thixotropic agent; S5. Preparation of temperature-sensitive microcapsule: glycerol monostearate is dissolved in ethanol, konjac gum is added, heating stirring is conducted for uniform mixing to obtain the ethanol phase; the thixotropic agent and the emulsifier are added into water for stirring mixing to obtain the water phase, the water phase is added dropwise into the ethanol phase, stirring is conducted, and then the mixture is placed in an ice water bath for filtration, washing and drying to obtain the temperature-sensitive microcapsule; The acrylic monomer includes methyl methacrylate, butyl acrylate, acrylamide, styrene and 1-allyl-3-methyl imidazole tetrafluoroborate, and the mass ratio is 3-5:4-6:2-4:1-2:2-4.

2. The demixing at ambient temperature preventing reticle coating according to claim 1, characterized in that, The mass ratio of the polyvinyl alcohol, boric acid and 1-hydroxyethyl-3-methyl imidazole chloride salt is 6-10:3-5:0.5-1.5, and the stirring reaction time is 2-4 h.

3. The demixing at ambient temperature preventing reticle coating according to claim 1, characterized in that, In step S1, the molar ratio of the trimellitic anhydride, trimethylolpropane and catalyst is 2-4:1:0.1-0.15, the catalyst is p-toluenesulfonic acid, and the temperature of the temperature-raising stirring reaction is 120-140 DEG C; in step S2, the mass ratio of the montmorillonite powder and the branched polyester is 10:1.5-2.5, and the temperature of the stirring reaction intercalation is 35-45 DEG C for 0.5-1.5 h.

4. The demixing at ambient temperature preventing reticle coating according to claim 1, characterized in that, The pH value of the Tris-HCl solution in step S3 is 8.5-9.5, the mass ratio of the fumed silica and tannic acid is 8-10:2-3, the temperature of the heated stirring reaction is 40-50℃, and the time is 3-5h; in step S4, the mass ratio of the modified fumed silica and intercalated montmorillonite powder is 3-5:6-8; in step S5, the mass ratio of the glycerol monostearate, konjac gum, thixotropic agent and emulsifier is 6-8:2-4:3-5:0.5-1, the emulsifier is selected from at least one of Tween-20, Tween-40, Tween-60, Tween-80 and Tween-85, and the temperature of the heating is 40-50℃.

5. The demixing at ambient temperature preventing reticle coating according to claim 1, characterized in that, The high molecular fiber is selected from at least one of polyester fiber, polyethylene fiber, polypropylene fiber and nylon fiber; the emulsifier is selected from at least one of Tween-20, Tween-40, Tween-60, Tween-80 and Tween-85; the initiator is selected from at least one of sodium persulfate, potassium persulfate and ammonium persulfate; the hollow glass microbead comprises hollow glass microbeads with an average particle size of 40-50μm and hollow glass microbeads with an average particle size of 100-150μm, and the mass ratio is 3-5:7-10.

6. A method for preparing a reticle coating for preventing ambient temperature delamination according to any one of claims 1 to 5, characterized in that, The method comprises the following steps: (1) uniformly mixing water and an emulsifier to prepare a pre-emulsion; (2) adding epoxy resin and acrylic monomer to the pre-emulsion and stirring to mix uniformly to prepare an emulsion; (3) adding temperature-sensitive microcapsules, nano-titanium dioxide, hollow glass microbeads, inorganic asbestos fibers and high molecular fibers to the emulsion and stirring to mix uniformly, adding an initiator and a water-soluble epoxy curing agent, heating and stirring to react, adding a temperature-sensitive reversible crosslinking agent and an additive, and stirring to mix uniformly to prepare a temperature-resistant marking paint.

7. The preparation method according to claim 6, characterized in that, The temperature of the heating is 50-80℃.

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