Composite coating with bionic adhesion and flame retardant functions and preparation method thereof

Abstract

The invention provides a composite coating with bionic adhesion and flame-retardant functions and a preparation method of the composite coating. The coating is prepared from the following components in parts by weight: 10 to 20 parts of core-shell microspheres, 5 to 10 parts of PCL (Polycaprolactone) grafted hydroxyapatite, 20 to 40 parts of water-soluble acrylate resin, 10 to 20 parts of deionized water, 5 to 10 parts of ethanol, 0.1 to 0.5 part of a de-foaming agent, 0.2 to 0.8 part of a flatting agent and 0.3 to 1.0 part of a thickening agent. According to the invention, the core-shell microspheres and PCL-grafted hydroxyapatite are added into the coating, the phosphate group of phosphate acrylate in the core-shell microspheres can improve the chemical adhesive force between a substrate and a coating, and the phosphate group has a certain flame retardant effect; and the coating of the PCL hydrophobic chain reduces the surface energy of the hydroxyapatite and improves the mechanical properties of the coating.

Description

Technical Field

[0001] This invention relates to the field of coatings, specifically to a composite coating with biomimetic adhesion and flame retardant functions and its preparation method. Background Technology

[0002] In modern industry and people's lives, coatings, as core materials for substrate protection, are facing an increasingly urgent need for functional integration. Whether it's building curtain walls, transportation vehicles, or electronic device housings, coatings must simultaneously possess stable adhesion properties and reliable safety protection capabilities. Among these, flame retardancy, as a key indicator for addressing fire risks, together with adhesion, constitutes the fundamental requirements for coating applications. The micro-nano setae structure of gecko foot pads and the sticky protein components of mussel byssal silks provide natural inspiration for the development of super-adhesive materials. Biomimetic adhesion technology, by simulating biological adhesion mechanisms, can significantly improve the bonding strength and durability of coatings with different substrates, solving the problems of traditional coatings being prone to peeling and having a short lifespan.

[0003] Many coating products on the market today suffer from limited functionality: while ordinary adhesive coatings can achieve adhesion to the substrate, they lack flame retardant properties and are prone to combustion and release toxic gases in high-temperature or open-flame environments; traditional flame-retardant coatings often sacrifice adhesion, relying on large amounts of inorganic flame-retardant fillers, resulting in weak bonding between the coating and the substrate, making them prone to cracking and peeling, and unable to meet the long-term use requirements under complex working conditions. Especially in fields with extremely high safety and reliability requirements, such as new energy vehicles and high-rise buildings, single-function coatings can no longer meet the needs of these scenarios. Developing composite coatings that combine excellent biomimetic adhesive properties with highly efficient flame-retardant performance has become an inevitable trend in the industry.

[0004] Current research and development of composite functional coatings faces technical bottlenecks such as poor compatibility between adhesive and flame-retardant components and insufficient functional synergy. Some attempts to achieve functional synergy through simple physical mixing are prone to component agglomeration and uneven dispersion, leading to decreased adhesion or flame-retardant efficiency. While chemical modification methods can improve compatibility, they are often complex, costly, and may introduce new environmental pollutants. Therefore, there is an urgent need to explore a novel composite system that, through the rational design of the structure and combination of biomimetic adhesive units and flame-retardant functional units, achieves efficient synergy between adhesion and flame-retardant properties while ensuring the environmental friendliness and workability of the coating, thus filling the relevant technological gaps. Summary of the Invention

[0005] Technical problem to be solved: The present invention provides a composite coating with biomimetic adhesion and flame retardant functions and its preparation method. By adding core-shell microspheres and PCL-grafted hydroxyapatite to the coating, the coating is endowed with biomimetic adhesion and flame retardant functions.

[0006] Technical solution: A composite coating with biomimetic adhesion and flame retardant functions comprises the following components by weight: 10-20 parts of core-shell microspheres 5-10 parts PCL-grafted hydroxyapatite 100-130 parts of water-soluble acrylate resin 10-20 parts deionized water 0.1 to 0.5 parts of defoamer Leveling agent 0.2~0.8 parts Thickener 0.3~1.0 parts.

[0007] Preferably, the defoamer is polydimethylsiloxane, the leveling agent is a polyether-modified silicone leveling agent, and the thickener is hydroxyethyl cellulose.

[0008] Preferably, the preparation of the core-shell microspheres includes the following steps: S1. PCL monomer and emulsifier are added to water and subjected to high-speed shearing to obtain core layer pre-emulsion; S2. The core layer pre-emulsion obtained in S1 is heated to 70~75℃ under nitrogen protection, then an initiator is added, and the reaction is carried out for 30~50 min to obtain the core layer seed emulsion; S3. Add phosphate ester-based acrylate, dopamine methacrylamide and emulsifier to water to obtain a shell pre-emulsified emulsion; S4. Heat the core seed emulsion obtained in S2 to 80-85℃, then add 10-20wt% of the shell pre-emulsified emulsion obtained in S3 and an initiator. After reacting for 20-40 minutes, add the remaining shell pre-emulsified emulsion and continue reacting for 2-3 hours. Then cool to room temperature, adjust the pH to 7-8, and filter to obtain core-shell microspheres.

[0009] Preferably, the method for preparing the PCL-grafted hydroxyapatite includes the following steps: S11. Dry hydroxyapatite is dispersed in anhydrous toluene, and ε-caprolactone monomer and stannous octoate are added under nitrogen protection, followed by ultrasonic dispersion to obtain a mixture. S12. The mixture obtained in S11 is heated to 110~130℃ and reacted for 10~18h. After centrifugation, PCL-grafted hydroxyapatite is obtained.

[0010] Preferably, the mass ratio of PCL monomer, emulsifier and water in S1 is 10~15:1~2:83~89; The emulsifier is any one or both of sodium dodecyl sulfate or nonylphenol polyoxyethylene ether. The shearing speed is 8000~10000 rpm, and the time is 15~20 min.

[0011] Preferably, the emulsifier in S2 is any one or both of sodium dodecyl sulfate or nonylphenol polyoxyethylene ether.

[0012] Preferably, the initiator in S2 is ammonium persulfate; And / or, the mass ratio of the core layer preemulsion to the initiator is 100:0.8~1.2.

[0013] Preferably, the mass ratio of phosphate ester acrylate, dopamine methacrylamide, emulsifier and water in S3 is 8~12:2~4:1~1.5:82.5~89; The emulsifier is sodium dodecylbenzenesulfonate.

[0014] Preferably, the mass ratio of the core seed emulsion to the shell pre-emulsified emulsion in S4 is 1:1.5~2.5.

[0015] Preferably, the mass ratio of hydroxyapatite, anhydrous toluene, ε-caprolactone monomer and stannous octoate in S11 is 1:20~30:5~8:0.05~0.1.

[0016] Beneficial effects: The present invention has the following advantages: 1. This invention prepares core-shell microspheres in which polyester lactone, as a soft, low-Tg core material, provides good elasticity and impact absorption; the hard shell formed by phosphate ester-based acrylate and dopamine methacrylamide possesses high Tg and crosslinking density, significantly improving the coating's hardness and scratch resistance. Furthermore, the soft core can deform locally under tension or impact, dispersing stress and preventing rapid crack propagation; the hard shell restricts excessive core flow, maintaining the integrity of the overall structure. 2. The phosphate groups in the phosphate-based acrylates of the core-shell microspheres in this invention can form phosphate bonds on the surface of substrates such as metals and ceramics, thereby improving the chemical adhesion between the substrate and the coating. In addition, the catechol structure of dopamine methacrylamide mimics the adhesive protein of mussels, maintaining strong adhesion even in humid or underwater environments. Furthermore, the phosphate groups themselves have a certain flame-retardant effect, and the amide chains of dopamine methacrylamide can form a cross-linked network at high temperatures, thereby improving heat resistance. The core-shell structure concentrates the flame retardant in the shell layer, forming a dense protective layer on the coating surface. 3. In this invention, PCL-grafted hydroxyapatite was prepared. Due to its high surface energy, the original hydroxyapatite nanoparticles are prone to agglomeration. The coating of PCL hydrophobic chains reduces the surface energy of hydroxyapatite, making it uniformly dispersed in the polymer matrix. Furthermore, PCL, as a flexible polymer layer, acts as a bridge between hydroxyapatite and the hydrophobic polymer matrix, reducing phase separation and improving the mechanical uniformity of the composite material. Detailed Implementation

[0017] The present invention will be further described below with reference to embodiments. These embodiments are illustrative of the present invention, but the present invention is not limited to these embodiments: Example 1

[0018] A composite coating with biomimetic adhesion and flame retardant functions comprises the following components by weight: 10 portions of core-shell microspheres 5 parts PCL-grafted hydroxyapatite 100 parts of water-soluble acrylate resin 10 parts deionized water 0.1 parts of polydimethylsiloxane 0.2 parts of polyether-modified silicone leveling agent 0.3 parts hydroxyethyl cellulose The preparation of the core-shell microspheres includes the following steps: S1. PCL monomer and emulsifier (sodium dodecyl sulfate) are added to water, wherein the mass ratio of PCL monomer, emulsifier and water is 10:1:83, and the core layer pre-emulsion is obtained by high-speed shearing at 8000 rpm for 15 min. S2. The core layer pre-emulsion obtained in S1 is heated to 70°C under nitrogen protection, and then an initiator (ammonium persulfate) is added. The mass ratio of the core layer pre-emulsion to the initiator is 100:0.8. The reaction is carried out for 30 minutes to obtain the core layer seed emulsion. S3. Add phosphate ester acrylate, dopamine methacrylamide and emulsifier (sodium dodecylbenzene sulfonate) to water, wherein the mass ratio of phosphate ester acrylate, dopamine methacrylamide, emulsifier and water is 8:2:1:83, to obtain a shell pre-emulsified emulsion. S4. The core seed emulsion obtained in S2 was heated to 80°C, and then 10 wt% of the shell pre-emulsified emulsion obtained in S3 and an initiator were added. After reacting for 20 min, the remaining shell pre-emulsified emulsion was added. The total mass ratio of the core seed emulsion to the shell pre-emulsified emulsion was 1:1.5. After reacting for 2 h, the mixture was cooled to room temperature, the pH was adjusted to 7, and the core-shell microspheres were obtained by filtration. The method for preparing the PCL-grafted hydroxyapatite includes the following steps: S11. The dried hydroxyapatite is dispersed in anhydrous toluene, and ε-caprolactone monomer and stannous octoate are added under nitrogen protection, wherein the mass ratio of hydroxyapatite, anhydrous toluene, ε-caprolactone monomer and stannous octoate is 1:20:5:0.05. The mixture is then ultrasonically dispersed to obtain a mixture. S12. The mixture obtained in S11 is heated to 110℃ and reacted for 10 hours. After centrifugation, PCL-grafted hydroxyapatite is obtained. Example 2

[0019] A composite coating with biomimetic adhesion and flame retardant functions comprises the following components by weight: 10 portions of core-shell microspheres 10 parts PCL-grafted hydroxyapatite 130 parts of water-soluble acrylate resin 12 parts deionized water 0.5 parts of polydimethylsiloxane 0.8 parts of polyether-modified silicone leveling agent Hydroxyethyl cellulose 1.0 part The preparation of the core-shell microspheres includes the following steps: S1. PCL monomer and emulsifier (sodium dodecyl sulfate) are added to water, wherein the mass ratio of PCL monomer, emulsifier and water is 15:2:89, and the core layer pre-emulsion is obtained by high-speed shearing at 10000rpm for 20min. S2. The core layer pre-emulsion obtained in S1 is heated to 75°C under nitrogen protection, and then an initiator (ammonium persulfate) is added. The mass ratio of the core layer pre-emulsion to the initiator is 100:1.2. The reaction is carried out for 50 min to obtain the core layer seed emulsion. S3. Add phosphate ester acrylate, dopamine methacrylamide and emulsifier (sodium dodecylbenzene sulfonate) to water, wherein the mass ratio of phosphate ester acrylate, dopamine methacrylamide, emulsifier and water is 12:4:1.5:89, to obtain a shell pre-emulsified emulsion. S4. The core seed emulsion obtained in S2 was heated to 85°C, and then 20 wt% of the shell pre-emulsified emulsion obtained in S3 and an initiator were added. After reacting for 240 min, the remaining shell pre-emulsified emulsion was added. The total mass ratio of the core seed emulsion to the shell pre-emulsified emulsion was 1:2.5. After reacting for 3 h, the mixture was cooled to room temperature, the pH was adjusted to 8, and the mixture was filtered to obtain core-shell microspheres. The method for preparing the PCL-grafted hydroxyapatite includes the following steps: S11. The dried hydroxyapatite was dispersed in anhydrous toluene, and ε-caprolactone monomer and stannous octoate were added under nitrogen protection, wherein the mass ratio of hydroxyapatite, anhydrous toluene, ε-caprolactone monomer and stannous octoate was 1:30:8:0.1. The mixture was then ultrasonically dispersed to obtain a mixture. S12. The mixture obtained in S11 is heated to 130℃ and reacted for 18 hours. After centrifugation, PCL-grafted hydroxyapatite is obtained. Example 3

[0020] A composite coating with biomimetic adhesion and flame retardant functions comprises the following components by weight: 18 portions of core-shell microspheres 8 parts PCL-grafted hydroxyapatite 110 parts of water-soluble acrylate resin 15 parts deionized water 0.4 parts of polydimethylsiloxane 0.6 parts of polyether-modified silicone leveling agent 0.7 parts hydroxyethyl cellulose The preparation of the core-shell microspheres includes the following steps: S1. PCL monomer and emulsifier (sodium dodecyl sulfate) are added to water, wherein the mass ratio of PCL monomer, emulsifier and water is 12:1:83, and the core layer pre-emulsion is obtained by high-speed shearing at 8000 rpm for 15 min. S2. The core layer pre-emulsion obtained in S1 is heated to 70°C under nitrogen protection, and then an initiator (ammonium persulfate) is added. The mass ratio of the core layer pre-emulsion to the initiator is 100:0.8. The reaction is carried out for 35 minutes to obtain the core layer seed emulsion. S3. Add phosphate ester acrylate, dopamine methacrylamide and emulsifier (sodium dodecylbenzene sulfonate) to water, wherein the mass ratio of phosphate ester acrylate, dopamine methacrylamide, emulsifier and water is 10:3:1:85, to obtain a shell pre-emulsified emulsion. S4. The core seed emulsion obtained in S2 was heated to 85°C, and then 15 wt% of the shell pre-emulsified emulsion obtained in S3 and an initiator were added. After reacting for 25 min, the remaining shell pre-emulsified emulsion was added. The total mass ratio of the core seed emulsion to the shell pre-emulsified emulsion was 1:2.5. After reacting for 3 h, the mixture was cooled to room temperature, the pH was adjusted to 8, and the mixture was filtered to obtain core-shell microspheres. The method for preparing the PCL-grafted hydroxyapatite includes the following steps: S11. The dried hydroxyapatite was dispersed in anhydrous toluene, and ε-caprolactone monomer and stannous octoate were added under nitrogen protection, wherein the mass ratio of hydroxyapatite, anhydrous toluene, ε-caprolactone monomer and stannous octoate was 1:25:6:0.08. The mixture was then ultrasonically dispersed to obtain a mixture. S12. The mixture obtained in S11 is heated to 120℃ and reacted for 15 hours. After centrifugation, PCL-grafted hydroxyapatite is obtained.

[0021] Example 4 A composite coating with biomimetic adhesion and flame retardant functions comprises the following components by weight: 15 portions of core-shell microspheres 5 parts PCL-grafted hydroxyapatite 100 parts of water-soluble acrylate resin 10 parts deionized water 0.1 parts of polydimethylsiloxane 0.3 parts of polyether-modified silicone leveling agent 0.3 parts hydroxyethyl cellulose The preparation of the core-shell microspheres includes the following steps: S1. PCL monomer and emulsifier (sodium dodecyl sulfate) are added to water, wherein the mass ratio of PCL monomer, emulsifier and water is 10:1:83, and the core layer pre-emulsion is obtained by high-speed shearing at 8000 rpm for 15 min. S2. The core layer pre-emulsion obtained in S1 is heated to 70°C under nitrogen protection, and then an initiator (ammonium persulfate) is added. The mass ratio of the core layer pre-emulsion to the initiator is 100:0.8. The reaction is carried out for 40 min to obtain the core layer seed emulsion. S3. Add phosphate ester-based acrylate, dopamine methacrylamide and emulsifier (sodium dodecylbenzene sulfonate) to water, wherein the mass ratio of phosphate ester-based acrylate, dopamine methacrylamide, emulsifier and water is 9:2:1:82.5, to obtain a shell pre-emulsified emulsion. S4. Heat the core seed emulsion obtained in S2 to 80℃, then add 10wt% of the shell pre-emulsified emulsion obtained in S3 and the initiator. After reacting for 20 min, continue to add the remaining shell pre-emulsified emulsion, wherein the total mass ratio of the core seed emulsion and the shell pre-emulsified emulsion is 1:1.5. Continue to react for 2 h, then cool to room temperature, adjust the pH to 8, and filter to obtain core-shell microspheres. The method for preparing the PCL-grafted hydroxyapatite includes the following steps: S11. The dried hydroxyapatite was dispersed in anhydrous toluene, and ε-caprolactone monomer and stannous octoate were added under nitrogen protection, wherein the mass ratio of hydroxyapatite, anhydrous toluene, ε-caprolactone monomer and stannous octoate was 1:30:8:0.1. The mixture was then ultrasonically dispersed to obtain a mixture. S12. The mixture obtained in S11 is heated to 110℃ and reacted for 10 hours. After centrifugation, PCL-grafted hydroxyapatite is obtained.

[0022] Example 5 A composite coating with biomimetic adhesion and flame retardant functions comprises the following components by weight: 10 portions of core-shell microspheres 10 parts PCL-grafted hydroxyapatite 120 parts of water-soluble acrylate resin 20 parts deionized water 0.5 parts of polydimethylsiloxane 0.8 parts of polyether-modified silicone leveling agent 0.5 parts hydroxyethyl cellulose The preparation of the core-shell microspheres includes the following steps: S1. PCL monomer and emulsifier (sodium dodecyl sulfate) are added to water, wherein the mass ratio of PCL monomer, emulsifier and water is 12:1:83, and the core layer pre-emulsion is obtained by high-speed shearing at 80000rpm for 15min. S2. The core layer pre-emulsion obtained in S1 is heated to 72°C under nitrogen protection, and then an initiator (ammonium persulfate) is added. The mass ratio of the core layer pre-emulsion to the initiator is 100:0.8. The reaction is carried out for 50 min to obtain the core layer seed emulsion. S3. Add phosphate ester acrylate, dopamine methacrylamide and emulsifier (sodium dodecylbenzene sulfonate) to water, wherein the mass ratio of phosphate ester acrylate, dopamine methacrylamide, emulsifier and water is 8:2:1:84, to obtain a shell pre-emulsified emulsion. S4. The core seed emulsion obtained in S2 was heated to 82°C, and then 10 wt% of the shell pre-emulsified emulsion obtained in S3 and an initiator were added. After reacting for 30 min, the remaining shell pre-emulsified emulsion was added. The total mass ratio of the core seed emulsion to the shell pre-emulsified emulsion was 1:2. After reacting for 2 h, the mixture was cooled to room temperature, the pH was adjusted to 7, and the core-shell microspheres were obtained by filtration. The method for preparing the PCL-grafted hydroxyapatite includes the following steps: S11. The dried hydroxyapatite is dispersed in anhydrous toluene, and ε-caprolactone monomer and stannous octoate are added under nitrogen protection, wherein the mass ratio of hydroxyapatite, anhydrous toluene, ε-caprolactone monomer and stannous octoate is 1:20:5:0.05. The mixture is then ultrasonically dispersed to obtain a mixture. S12. The mixture obtained in S11 is heated to 115℃ and reacted for 18 hours. After centrifugation, PCL-grafted hydroxyapatite is obtained. Example 6

[0023] A composite coating with biomimetic adhesion and flame retardant functions comprises the following components by weight: 10 portions of core-shell microspheres 5 parts PCL-grafted hydroxyapatite 100 parts of water-soluble acrylate resin 20 parts deionized water 0.5 parts of polydimethylsiloxane 0.8 parts of polyether-modified silicone leveling agent Hydroxyethyl cellulose 1.0 part The preparation of the core-shell microspheres includes the following steps: S1. PCL monomer and emulsifier (sodium dodecyl sulfate) are added to water, wherein the mass ratio of PCL monomer, emulsifier and water is 10:1:89, and the core layer pre-emulsion is obtained by high-speed shearing at 10000rpm for 20min. S2. The core layer pre-emulsion obtained in S1 is heated to 75°C under nitrogen protection, and then an initiator (ammonium persulfate) is added. The mass ratio of the core layer pre-emulsion to the initiator is 100:1.2. The reaction is carried out for 50 min to obtain the core layer seed emulsion. S3. Add phosphate ester acrylate, dopamine methacrylamide and emulsifier (sodium dodecylbenzene sulfonate) to water, wherein the mass ratio of phosphate ester acrylate, dopamine methacrylamide, emulsifier and water is 12:4:1.5:89, to obtain a shell pre-emulsified emulsion. S4. The core seed emulsion obtained in S2 was heated to 84℃, and then 15wt% of the shell pre-emulsified emulsion obtained in S3 and an initiator were added. After reacting for 28 min, the remaining shell pre-emulsified emulsion was added. The total mass ratio of the core seed emulsion to the shell pre-emulsified emulsion was 1:1.5. After reacting for 2 h, the mixture was cooled to room temperature, the pH was adjusted to 8, and the mixture was filtered to obtain core-shell microspheres. The method for preparing the PCL-grafted hydroxyapatite includes the following steps: S11. The dried hydroxyapatite was dispersed in anhydrous toluene, and ε-caprolactone monomer and stannous octoate were added under nitrogen protection, wherein the mass ratio of hydroxyapatite, anhydrous toluene, ε-caprolactone monomer and stannous octoate was 1:30:8:0.1. The mixture was then ultrasonically dispersed to obtain a mixture. S12. The mixture obtained in S11 is heated to 120℃ and reacted for 15 hours. After centrifugation, PCL-grafted hydroxyapatite is obtained.

[0024] Example 7 A composite coating with biomimetic adhesion and flame retardant functions comprises the following components by weight: 10 portions of core-shell microspheres 8 parts PCL-grafted hydroxyapatite 100 parts of water-soluble acrylate resin 10 parts deionized water 0.1 parts of polydimethylsiloxane 0.2 parts of polyether-modified silicone leveling agent 0.3 parts hydroxyethyl cellulose The preparation of the core-shell microspheres includes the following steps: S1. PCL monomer and emulsifier (sodium dodecyl sulfate) are added to water, wherein the mass ratio of PCL monomer, emulsifier and water is 15:1:83, and the core layer pre-emulsion is obtained by high-speed shearing at 8000 rpm for 20 min. S2. The core layer pre-emulsion obtained in S1 is heated to 75°C under nitrogen protection, and then an initiator (ammonium persulfate) is added. The mass ratio of the core layer pre-emulsion to the initiator is 100:1.2. The reaction is carried out for 50 min to obtain the core layer seed emulsion. S3. Add phosphate ester acrylate, dopamine methacrylamide and emulsifier (sodium dodecylbenzene sulfonate) to water, wherein the mass ratio of phosphate ester acrylate, dopamine methacrylamide, emulsifier and water is 12:4:1:89, to obtain a shell pre-emulsified emulsion. S4. The core seed emulsion obtained in S2 was heated to 85°C, and then 18 wt% of the shell pre-emulsified emulsion obtained in S3 and an initiator were added. After reacting for 20 min, the remaining shell pre-emulsified emulsion was added. The total mass ratio of the core seed emulsion to the shell pre-emulsified emulsion was 1:1.5. After reacting for 2 h, the mixture was cooled to room temperature, the pH was adjusted to 7, and the core-shell microspheres were obtained by filtration. The method for preparing the PCL-grafted hydroxyapatite includes the following steps: S11. The dried hydroxyapatite was dispersed in anhydrous toluene, and ε-caprolactone monomer and stannous octoate were added under nitrogen protection, wherein the mass ratio of hydroxyapatite, anhydrous toluene, ε-caprolactone monomer and stannous octoate was 1:20:6:0.08. The mixture was then ultrasonically dispersed to obtain a mixture. S12. The mixture obtained in S11 is heated to 110℃ and reacted for 10 hours. After centrifugation, PCL-grafted hydroxyapatite is obtained.

[0025] Comparative Example 1 The difference between this comparative example and Example 7 is that core-shell microspheres were not added.

[0026] Comparative Example 2 The difference between this comparative example and Example 7 is that PCL-grafted hydroxyapatite was not added.

[0027] Comparative Example 3 The difference between this comparative example and Example 7 is that PCL-grafted hydroxyapatite was not added and core-shell microspheres were not added.

[0028] Comparative Example 4 The difference between this comparative example and Example 7 is that PCL was not grafted onto the surface of hydroxyapatite, but hydroxyapatite was added directly.

[0029] Comparative Example 5 The difference between this comparative example and Example 7 is that phosphate ester acrylate was not added in S3.

[0030] Comparative Example 6 The difference between this comparative example and Example 7 is that dopamine methacrylamide was not added in S3.

[0031] Performance testing Performance tests were conducted on Examples 1-7 and Comparative Examples 1-6 obtained in this invention, and the results are shown in the table below.

[0032] Table 1

[0033] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A composite coating with biomimetic adhesion and flame retardant functions, characterized in that: By weight, it contains the following components: 10-20 parts of core-shell microspheres 5-10 parts PCL-grafted hydroxyapatite 100-130 parts of water-soluble acrylate resin 10-20 parts deionized water 0.1 to 0.5 parts of defoamer Leveling agent 0.2~0.8 parts Thickener 0.3~1.0 parts.

2. The method for preparing the composite coating with biomimetic adhesion and flame retardant functions according to claim 1, characterized in that: The defoamer is polydimethylsiloxane, the leveling agent is polyether-modified silicone leveling agent, and the thickener is hydroxyethyl cellulose.

3. The method for preparing the composite coating with biomimetic adhesion and flame retardant functions according to claim 1, characterized in that: The preparation of the core-shell microspheres includes the following steps: S1. PCL monomer and emulsifier are added to water and subjected to high-speed shearing to obtain core layer pre-emulsion; S2. The core layer pre-emulsion obtained in S1 is heated to 70~75℃ under nitrogen protection, then an initiator is added, and the reaction is carried out for 30~50 min to obtain the core layer seed emulsion; S3. Add phosphate ester-based acrylate, dopamine methacrylamide and emulsifier to water to obtain a shell pre-emulsified emulsion; S4. Heat the core seed emulsion obtained in S2 to 80-85℃, then add 10-20wt% of the shell pre-emulsified emulsion obtained in S3 and an initiator. After reacting for 20-40 minutes, add the remaining shell pre-emulsified emulsion and continue reacting for 2-3 hours. Then cool to room temperature, adjust the pH to 7-8, and filter to obtain core-shell microspheres.

4. The method for preparing the composite coating with biomimetic adhesion and flame retardant functions according to claim 1, characterized in that: The method for preparing the PCL-grafted hydroxyapatite includes the following steps: S11. Dry hydroxyapatite is dispersed in anhydrous toluene, and ε-caprolactone monomer and stannous octoate are added under nitrogen protection, followed by ultrasonic dispersion to obtain a mixture. S12. The mixture obtained in S11 is heated to 110~130℃ and reacted for 10~18h. After centrifugation, PCL-grafted hydroxyapatite is obtained.

5. The method for preparing the composite coating with biomimetic adhesion and flame retardant functions according to claim 3, characterized in that: The mass ratio of PCL monomer, emulsifier and water in S1 is 10~15:1~2:83~89; And / or, the emulsifier is any one or both of sodium dodecyl sulfate or nonylphenol polyoxyethylene ether; And / or, the shearing speed is 8000~10000 rpm, and the time is 15~20 min.

6. The method for preparing the composite coating with biomimetic adhesion and flame retardant functions according to claim 3, characterized in that: The emulsifier in S2 is any one or both of sodium dodecyl sulfate or nonylphenol polyoxyethylene ether.

7. The method for preparing the composite coating with biomimetic adhesion and flame retardant functions according to claim 3, characterized in that: The initiator in S2 is ammonium persulfate; And / or, the mass ratio of the core layer preemulsion to the initiator is 100:0.8~1.

2.

8. The method for preparing the composite coating with biomimetic adhesion and flame retardant functions according to claim 3, characterized in that: The mass ratio of phosphate ester acrylate, dopamine methacrylamide, emulsifier and water in S3 is 8~12:2~4:1~1.5:82.5~89; And / or, the emulsifier is sodium dodecylbenzenesulfonate.

9. The method for preparing the composite coating with biomimetic adhesion and flame retardant functions according to claim 3, characterized in that: The mass ratio of the core seed emulsion to the shell pre-emulsified emulsion in S4 is 1:1.5~2.

5.

10. The method for preparing the composite coating with biomimetic adhesion and flame retardant functions according to claim 3, characterized in that: The mass ratio of hydroxyapatite, anhydrous toluene, ε-caprolactone monomer, and stannous octoate in S11 is 1:20~30:5~8:0.05~0.1.

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