Intelligent antifouling paint based on pH response microcapsule and self-repairing hydrogel and preparation method of intelligent antifouling paint
Through the intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogels, the problems of uncontrollable release and self-healing failure of traditional coatings in alkaline environments are solved, and efficient antifouling effect and environmental protection performance are achieved. It is suitable for hulls and marine structures in polar and complex marine environments.
Patent Information
- Application Number
- CN202511016049.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-23
- Publication Date
- 2025-10-10
AI Technical Summary
Traditional antifouling coatings for ships have problems such as uncontrollable release of agents, poor biological targeting, and failure of self-repairing components in humid and hot environments. In particular, the environment induced by barnacle attachment in alkaline environments is not accurately utilized, the microcapsules have poor dispersion stability in the coating, and the self-repair rate is insufficient.
An intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogels is used. By designing microcapsules with a capsaicin core, a sodium alginate/chitosan core layer and a nano-SiO2 shell layer, combined with glutaraldehyde cross-linked chitosan hydrogel, pH-responsive release and self-healing capabilities are achieved, and nano-TiO2 is added to improve stability.
It achieves precise release of antifouling agents in alkaline environments, with a self-repair rate of up to 92%, reducing antifouling costs, meeting environmental protection standards, and is suitable for long-term antifouling needs in polar and complex marine environments.
Smart Images
Figure CN120758120A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of marine heavy antifouling materials, and in particular to an intelligent antifouling coating based on pH-responsive microcapsules and self-repairing hydrogels, and a preparation method thereof. Background Art
[0002] Traditional ship antifouling coatings have three major pain points: uncontrollable release of agents, poor biological targeting (broad-spectrum toxicity that harms the ecology), and difficulty in repairing mechanical damage:
[0003] 1. The alkaline environment (pH 8.7-9.2) induced by barnacle attachment is not accurately utilized;
[0004] 2. The dispersion stability of microcapsules in the coating is poor (settling rate > 30% in 6 months);
[0005] 3. The self-repairing component fails in a hot and humid environment (repair rate <50%).
[0006] Based on the above problems, it is urgent to develop smart antifouling coatings based on pH-responsive microcapsules and self-healing hydrogels. Summary of the Invention
[0007] In order to solve the above technical problems, the present invention provides an intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogels and a preparation method thereof.
[0008] To achieve the above object, the present invention is implemented according to the following technical solutions:
[0009] The first technical solution provided by the present invention is an intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogels, comprising the following components in parts by weight:
[0010] 100 parts of epoxy resin;
[0011] pH-responsive microcapsules 5-20 copies;
[0012] 10-30 parts of self-healing hydrogel;
[0013] 1-3 parts of coating dispersant.
[0014] Furthermore, the pH-responsive microcapsule consists of a capsaicin core, a sodium alginate / chitosan core layer and a nano-SiO2 shell layer from the inside to the outside.
[0015] Furthermore, the self-repairing hydrogel is made of glutaraldehyde cross-linked chitosan with a cross-linking degree of 20-40% and a swelling ratio of ≤120%.
[0016] Preferably, the coating dispersant is dispersant BYK-163.
[0017] Preferably, the particle size distribution D50 of the pH-responsive microcapsules is 10-20 μm; the thickness of the nano-SiO2 shell is 50-100 nm, and the pore size is 3-6 nm.
[0018] Furthermore, the coating also includes 4-6 parts of nano-TiO2.
[0019] Preferably, the particle size of the nano-TiO2 is 20-50 nm.
[0020] The second technical solution provided by the present invention is a method for preparing an intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogels, comprising the following steps:
[0021] S1. Preparation of pH-responsive microcapsules: 1.0 g of sodium alginate was dissolved in 100 ml of deionized water, stirred at 50°C for 2 h, 0.5 g of capsaicin and 2.0 g of chitosan were added, and high-pressure homogenization (1000 bar, 3 cycles) was performed to form an emulsion; the emulsion was added dropwise to a TEOS / ethanol solution with a molar ratio of 1:20, and then 0.1 M HCl was added to adjust the pH to 3.5. The mixture was reacted at 40°C for 6 h, and the microcapsules were collected by centrifugation at 8000 rpm for 10 min; the microcapsules were immersed in a 0.5 wt% PEG-4000 ethanol solution and then vacuum-dried at 60°C to a moisture content of <3% to obtain pH-responsive microcapsules;
[0022] S2, premixing the pH-responsive microcapsules with the self-healing hydrogel and the coating dispersant to form a premixed solution;
[0023] S3. Add epoxy resin dropwise to the premixed liquid and stir at a shear rate of 2000 rpm to obtain an intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogel.
[0024] Furthermore, in step S2, the premix is dispersed under ultrasonic conditions at a frequency of 40 kHz for 30 minutes.
[0025] The third technical solution provided by the present invention is a method for preparing an intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogels, comprising the following steps:
[0026] S1, preparation of pH-responsive microcapsules: 1.0 g of sodium alginate was dissolved in 100 ml of deionized water at 50℃ for 2 h, 0.5 g of capsaicin and 2.0 g of chitosan were added, and an emulsion was formed by high-pressure homogenization (1000 bar, 3 cycles); the emulsion was added dropwise into a TEOS / ethanol solution with a molar ratio of 1:20, then 0.1 M HCl was added to adjust the pH to 3.5, and the reaction was carried out at 40℃ for 6 h; the microcapsules were collected by centrifugation at 8000 rpm for 10 min; the microcapsules were immersed in a 0.5wt% PEG-4000 ethanol solution and then vacuum dried at 60℃ until the water content was <3%, to obtain pH-responsive microcapsules;
[0027] S2, pre-mixing the pH-responsive microcapsules with the self-healing hydrogel, the paint dispersant and nano-TiO2 to form a pre-mixed solution;
[0028] S3, adding epoxy resin dropwise to the pre-mixed solution and stirring at a shear rate of 2000 rpm to obtain an intelligent antifouling paint based on pH-responsive microcapsules and self-healing hydrogel.
[0029] Compared with the prior art, the present application has the following beneficial effects:
[0030] 1. The paint of the present application has pH-responsive release, self-repairing ability and environmental adaptability, which is specifically embodied in the targeted triggering of the pH-responsive microcapsules: the sodium alginate / chitosan core dissolves and releases capsaicin at pH>8.5; precise controlled release: the nano-SiO2 shell layer of the pH-responsive microcapsules realizes zero-order release kinetics; dynamic hydrogen bond network: glutaraldehyde cross-linked chitosan hydrogel realizes scratch self-healing;
[0031] 2. The paint of the present application does not contain organic tin, copper and other metal toxic components, and meets the environmental protection antifouling standard; experimental results show that the paint of the present application exhibits excellent antifouling and anti-algal performance in 6-week real sea test after spraying and film forming, the 24h repair rate is >92%, the measured ship 5-year maintenance-free, the barnacle attachment area is <3%, the antifouling cost is reduced by more than 40% compared with traditional paint, and the IMO 2025 environmental protection limit requirement is met; it is especially suitable for long-term antifouling of ship hulls, marine structures, seawater pipelines and the like in polar and complex marine environments.
[0032] 3. In addition, the introduction of nano-TiO2 with ultraviolet shielding effect in the paint of the present application helps to improve the stability of the coating under long-term exposure to sunlight, delay the degradation process of functional components (such as pH-responsive microcapsules or self-healing hydrogel), and thus enhance the antifouling function and service life of the paint. BRIEF DESCRIPTION OF DRAWINGS
[0033] Figure 1 Structure profile of the pH-responsive microcapsules of Example 1.
[0034] Figure 2TEM image of the pH-responsive microcapsule of Example 1.
[0035] Figure 3 Particle size distribution graph of the pH-responsive microcapsule of Example 1.
[0036] Figure 4 pH-responsive release curve of the pH-responsive microcapsule of Example 1.
[0037] Figure 5 Self-repairing rate over time curve of the coating of Example 1.
[0038] Figure 6 Comparison chart of barnacle and algae attachment experiment images of the coating of Example 1. DETAILED DESCRIPTION
[0039] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to examples. The specific examples described herein are only used to explain the present application and do not limit the present application.
[0040] Example 1
[0041] S1, Preparation of pH-responsive microcapsule: 1.0 g of sodium alginate was dissolved in 100 ml of deionized water, stirred at 50°C for 2 h, 0.5 g of capsaicin and 2.0 g of chitosan were added, and an emulsion was formed by high-pressure homogenization (1000 bar, 3 cycles); the emulsion was added dropwise into a TEOS / ethanol solution with a molar ratio of 1:20, then 0.1 M of HCl was added to adjust the pH to 3.5, and the reaction was carried out at 40°C for 6 h; the microcapsules were collected by centrifugation at 8000 rpm for 10 min; the microcapsules were immersed in a 0.5 wt% PEG-4000 ethanol solution and then vacuum dried at 60°C until the water content was <3%, to obtain the pH-responsive microcapsule; the structure profile of the pH-responsive microcapsule prepared in this example is shown in Figure 1 , which is composed of a capsaicin core 1 (red), a sodium alginate / chitosan core layer 2 (yellow), and a nano-SiO2 shell layer 3 (gray porous structure) from inside to outside; the TEM image of the pH-responsive microcapsule is shown in Figure 2 , which shows that the nano-SiO2 shell layer of the pH-responsive microcapsule has a shell thickness of 85±5 nm; Figure 1 The capsule diameter of the pH-responsive microcapsule was determined by a laser particle size analyzer to be 15.2±1.3 μm; the pore size of the pH-responsive microcapsule was determined by a conventional BET nitrogen adsorption method to be 4.8±0.7 nm. The microcapsule particle size distribution graph of the pH-responsive microcapsule prepared in this example is shown in Figure 3 , which shows that the D50 particle size distribution microcapsule has a particle size distribution in the range of 4-6 μm, and the CV value is less than 10%, with high distribution stability. Figure 3
[0042] Furthermore, in order to test the pH response effect of the pH responsive microcapsules prepared in this embodiment, the pH response release curve was measured at 25°C under the conditions of pH = 8.7 artificial seawater. Figure 4 As shown, the release was <5% at pH 8.0 and >90% at pH 8.7 within 24 h.
[0043] S2. Premix 15 g of pH-responsive microcapsules with 20 g of glutaraldehyde-crosslinked chitosan (crosslinking degree 30%) and 1.5 g of coating dispersant BYK-163 to form a premixed solution;
[0044] S3. Add 100 g of epoxy resin E-44 dropwise to the premixed solution and stir at a shear rate of 2000 rpm to obtain an intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogel.
[0045] When in use, the coating slurry is applied to the surface of a steel plate substrate or other substrate, dried and solidified to form an antifouling coating.
[0046] 1. Antifouling performance test (according to ISO 11306 "Evaluation of coating performance in seawater environment")
[0047] The smart antifouling coating based on pH-responsive microcapsules and self-healing hydrogels of this embodiment was sprayed to a film thickness of 200±10 μm (GB / T 13452.2). The antifouling performance test was conducted in accordance with ISO 11306 "Evaluation of Coating Performance in Seawater Environments". During the test, the commercially available Econea coating (certified by the International Maritime Organization) was used as a comparison. The test results are shown in Tables 1 and Figure 6 shown.
[0048] Table 1
[0049] Test items The present invention Comparative Example (Econea) Test standards Barnacle attachment density <![CDATA[2.1个 / 100cm 2 ]]> <![CDATA[32.7个 / 100cm 2 ]]> ASTM D6990 Algal coverage ＜5％ 45％ ISO 10253 Bacterial biofilm thickness 1.8 μm 15.4 μm CLSM observation
[0050] From Table 1 and Figure 6 It can be seen that the barnacle attachment area of the smart antifouling coating based on pH-responsive microcapsules and self-healing hydrogel in this embodiment is less than 3%, which reduces the antifouling cost by more than 40% compared with traditional coatings.
[0051] 2. Self-repair performance verification, the test results are shown in Table 2 and Figure 5 shown.
[0052]
[0053]
[0054] From Table 2 and Figure 5 It can be seen that the 24-hour repair rate of the smart antifouling coating based on pH-responsive microcapsules and self-healing hydrogel in this embodiment is greater than 92%.
[0055] In summary, the intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogels of the present invention breaks through the industry difficulties of "uncontrollable release" and "damage failure" through the bionic intelligent response + self-healing synergistic mechanism, providing a new generation of antifouling solutions for green ships, which is suitable for the long-term antifouling needs of hulls, marine structures, seawater pipelines, etc. in polar and complex marine environments.
[0056] Example 2
[0057] The difference from Example 1 is that nano-TiO2 with UV shielding effect is introduced into the coating. The specific preparation process is as follows:
[0058] S1. Preparation of pH-responsive microcapsules: 1.0 g of sodium alginate was dissolved in 100 ml of deionized water, stirred at 50°C for 2 h, 0.5 g of capsaicin and 2.0 g of chitosan were added, and high-pressure homogenization (1000 bar, 3 cycles) was performed to form an emulsion; the emulsion was added dropwise to a TEOS / ethanol solution with a molar ratio of 1:20, and then 0.1 M HCl was added to adjust the pH to 3.5. The mixture was reacted at 40°C for 6 h, and the microcapsules were collected by centrifugation at 8000 rpm for 10 min; the microcapsules were immersed in a 0.5 wt% PEG-4000 ethanol solution and then vacuum-dried at 60°C to a moisture content of <3% to obtain pH-responsive microcapsules;
[0059] S2, premixing 15 g of pH-responsive microcapsules with 20 g of glutaraldehyde-crosslinked chitosan (crosslinking degree 30%), 1.5 g of coating dispersant BYK-163, and 15 g of nano-TiO2 (particle size 30 nm) to form a premixed solution;
[0060] S3. Add 100 g of epoxy resin E-44 dropwise to the premixed solution and stir at a shear rate of 2000 rpm to obtain an intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogel.
[0061] It helps to improve the stability of the coating under long-term exposure to sunlight and delay the degradation process of functional components (such as pH-responsive microcapsules or self-healing hydrogels), thereby enhancing the antifouling function and service life of the coating.
[0062] The technical solution of the present invention is not limited to the above-mentioned specific embodiments. Any technical variations made according to the technical solution of the present invention fall within the protection scope of the present invention.
Claims
1. An intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogels, characterized in that: The composition comprises the following components in parts by weight: 100 parts of epoxy resin; pH-responsive microcapsules 5-20 copies; 10-30 parts of self-healing hydrogel; 1-3 parts of coating dispersant.
2. The smart antifouling coating based on pH-responsive microcapsules and self-healing hydrogel according to claim 1, characterized in that: The pH-responsive microcapsule consists of a capsaicin core, a sodium alginate / chitosan core layer and a nano-SiO2 shell layer in sequence from the inside to the outside.
3. The smart antifouling coating based on pH-responsive microcapsules and self-healing hydrogel according to claim 1, characterized in that: The self-repairing hydrogel is made of glutaraldehyde cross-linked chitosan with a cross-linking degree of 20-40% and a swelling ratio of ≤120%.
4. The smart antifouling coating based on pH-responsive microcapsules and self-healing hydrogel according to claim 1, characterized in that: The coating dispersant is dispersant BYK-163.
5. The smart antifouling coating based on pH-responsive microcapsules and self-healing hydrogel according to claim 2, characterized in that: The particle size distribution D50 of the pH-responsive microcapsule is 10-20 μm; the thickness of the nano-SiO2 shell is 50-100 nm, and the pore size is 3-6 nm.
6. The smart antifouling coating based on pH-responsive microcapsules and self-healing hydrogel according to any one of claims 1 to 5, characterized in that: The coating also includes 4-6 parts of nano-TiO2.
7. The smart antifouling coating based on pH-responsive microcapsules and self-healing hydrogel according to claim 6, characterized in that: The particle size of the nano-TiO2 is 20-50nm.
8. A method for preparing an intelligent antifouling coating based on pH-responsive microcapsules and self-repairing hydrogel according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Preparation of pH-responsive microcapsules: 1.0 g of sodium alginate was dissolved in 100 ml of deionized water and stirred at 50°C for 2 h. 0.5 g of capsaicin and 2.0 g of chitosan were added and homogenized under high pressure (1000 bar, 3 cycles) to form an emulsion. The emulsion was then added dropwise to a TEOS / ethanol solution with a molar ratio of 1:
20. 0.1 M HCl was then added to adjust the pH to 3.
5. The mixture was reacted at 40°C for 6 h and centrifuged at 8000 rpm for 10 min to collect the microcapsules. The microcapsules were immersed in a 0.5 wt% PEG-4000 ethanol solution and then vacuum dried at 60°C until the moisture content was less than 3% to obtain pH-responsive microcapsules. S2, premixing the pH-responsive microcapsules with the self-healing hydrogel and the coating dispersant to form a premixed solution; S3. Add epoxy resin dropwise to the premixed liquid and stir at a shear rate of 2000 rpm to obtain an intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogel.
9. The method for preparing the smart antifouling coating based on pH-responsive microcapsules and self-repairing hydrogel according to claim 8, characterized in that: In step S2, the premix is dispersed under ultrasonic conditions at a frequency of 40 kHz for 30 minutes.
10. A method for preparing an intelligent antifouling coating based on pH-responsive microcapsules and self-repairing hydrogels according to claim 6 or 7, characterized in that: The following steps are involved: S1. Preparation of pH-responsive microcapsules: 1.0 g of sodium alginate was dissolved in 100 ml of deionized water and stirred at 50°C for 2 h. 0.5 g of capsaicin and 2.0 g of chitosan were added and homogenized under high pressure (1000 bar, 3 cycles) to form an emulsion. The emulsion was then added dropwise to a TEOS / ethanol solution with a molar ratio of 1:
20. 0.1 M HCl was then added to adjust the pH to 3.
5. The mixture was reacted at 40°C for 6 h and centrifuged at 8000 rpm for 10 min to collect the microcapsules. The microcapsules were immersed in a 0.5 wt% PEG-4000 ethanol solution and then vacuum dried at 60°C until the moisture content was less than 3% to obtain pH-responsive microcapsules. S2, premixing the pH-responsive microcapsules with the self-healing hydrogel, the coating dispersant and nano-TiO2 to form a premixed solution; S3. Add epoxy resin dropwise to the premixed liquid and stir at a shear rate of 2000 rpm to obtain an intelligent antifouling coating based on pH-responsive microcapsules and self-healing hydrogel.