High-stability self-repairing microcapsule with photothermal effect as well as preparation method and application of high-stability self-repairing microcapsule
By constructing a polyaniline shell and nano-TiO2 modification in the self-healing microcapsule shell and combining it with the photothermal effect, the problems of microcapsule stability and single function are solved, and high stability and multifunctionality are achieved, which is suitable for rapid heating and UV shielding of composite materials.
Patent Information
- Application Number
- CN202510816558.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-18
- Publication Date
- 2025-09-23
Smart Images
Figure CN120679439A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of self-repairing microcapsules, and in particular relates to a high-stability self-repairing microcapsule with a photothermal effect, a preparation method thereof, and an application thereof. Background Art
[0002] Among self-healing materials, microcapsules, with their unique "damage-triggered" core material release-self-repair mechanism, have become a key technology in high-value fields such as aerospace, electronic packaging, and biomedicine. However, existing self-healing microcapsule systems suffer from insufficient stability and limited functionality, severely hindering their industrial application.
[0003] Self-repair methods for microcapsules include two-component microcapsule repair, phase change repair, and external response repair. Ultraviolet light response repair has become an efficient and practical repair method due to its rapid response, environmental friendliness, and cost-effectiveness. The stability of the microcapsule greatly affects its repair effect. The stability of the microcapsule is affected by the stability of the internal core material on the one hand, and the ultraviolet light shielding ability of the external shell material on the other. Currently, the commonly used method is to modify the shell material with inorganic materials such as nano-TiO2 or ZnO to give the shell material a certain ultraviolet shielding ability, but it still cannot meet the requirements of long-term stable operation. In addition, self-repairing microcapsules only repair material damage through repair agents, and their function is single.
[0004] In summary, the development of self-healing microcapsule systems with excellent environmental stability and multifunctional properties is of great significance for promoting the application of self-healing materials in high-end fields. Summary of the Invention
[0005] In response to the above-mentioned problems existing in the prior art, the present invention provides a high-stability self-repairing microcapsule with photothermal effect, and a preparation method and application thereof, so that the microcapsule has both high stability and UV shielding ability.
[0006] To achieve the above-mentioned purpose, the technical solution provided by the present invention is as follows:
[0007] In a first aspect, the present application provides a method for preparing highly stable self-repairing microcapsules with a photothermal effect, comprising the following steps:
[0008] S1: diisocyanate, hydroxyl acrylate monomer, and isooctyl acrylate are mixed, reacted and polymerized under the action of a catalyst, and then a photoinitiator is added to the mixture to obtain a photosensitive core material;
[0009] S2: adding TDI prepolymer, the photosensitive core material, and amphiphilic TiO2 to an organic solvent and mixing to obtain an oil phase; mixing an emulsifier with water to obtain an aqueous phase, and using the oil phase as a dispersed phase and the aqueous phase as a continuous phase to obtain an oil-in-water emulsion; mixing the oil-in-water emulsion with a small molecule polyol, performing an addition reaction, filtering, and drying to obtain TiO2@polyurethane photosensitive microcapsules;
[0010] S3: dissolving an anionic surfactant in water, adding the TiO2@polyurethane photosensitive microcapsules to react at 40-50°C, and then filtering and drying to obtain anion-attached microcapsules; in situ polymerizing aniline on the surface of the anion-attached microcapsules, washing and drying to obtain the high-stability self-healing microcapsules with photothermal effect.
[0011] Optionally, the molar ratio of the diisocyanate, the hydroxy acrylate monomer, and the isooctyl acrylate is 1:1:(0.75-1.5).
[0012] Optionally, the reaction polymerization conditions in S1 include: reacting at 55-65°C for 12-24 hours.
[0013] Optionally, the diisocyanate includes isophorone diisocyanate; and the hydroxy acrylate monomer includes one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxyethyl acrylate.
[0014] Optionally, the catalyst is an organometallic catalyst.
[0015] Optionally, the catalyst includes one or more of butyl ditin dilaurate, stannous octoate and dibutyl glycol titanium diacetate.
[0016] Optionally, the photoinitiator includes one or more of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, 1-hydroxy-cyclohexyl-phenyl ketone, 2-hydroxy-2-methyl-1-naphthyl-1-propanone and benzoin dimethyl ether.
[0017] Optionally, the amount ratio of the photoinitiator added to the hydroxy acrylate monomer added is (0.01-0.03):1.
[0018] Optionally, in the oil phase, the mass ratio of TDI prepolymer, photosensitive core material, and amphiphilic TiO2 is 1:(2.5-4):(0.1-0.3).
[0019] Optionally, in S2, the conditions of the addition reaction include: reacting at 65-70°C for 0.5-2 h.
[0020] Optionally, in S2, the organic solvent includes one or more of chlorobenzene, cyclohexane and toluene.
[0021] Optionally, the small molecule polyol includes 1,4-butanediol, and the oil-in-water emulsion and the small molecule polyol are mixed according to a mass ratio of TDI prepolymer to small molecule polyol of 4.5:(3.2-3.8).
[0022] Optionally, the emulsifier is gum arabic, sodium alginate or polyvinyl alcohol, and the mass volume ratio of the emulsifier to water in the aqueous phase is (7-8):100 g / mL.
[0023] Optionally, in S3, the ratio of the amount of aniline to the mass of the anion-attached microcapsules is (0.01-0.02) mol:10 g.
[0024] Optionally, the anionic surfactant includes one or more of sodium dodecylbenzenesulfonate, sodium lauryl sulfate and sodium alkylbenzenesulfonate.
[0025] In a second aspect, the present application provides a high-stability self-repairing microcapsule with photothermal effect prepared by the method described in the first aspect.
[0026] In a third aspect, the present application provides an application of the high-stability self-repairing microcapsules with photothermal effect described in the second aspect in a composite material.
[0027] Compared with the prior art, this application has at least the following beneficial effects:
[0028] The present invention modifies the shell with inorganic materials to obtain ultraviolet shielding ability, and then constructs a polyaniline shell layer with high ultraviolet shielding ability to increase the stability of its internal core material. The ultraviolet light absorption of its outer shell is significantly increased. Long-term tests show that under natural light environment, the core material loss does not exceed 3% after two months.
[0029] The microcapsules of this invention possess excellent photothermal conversion capabilities, enabling rapid non-contact heating (rapidly heating to 106.4°C within 40 seconds). The carbonyl groups (C=O) in the polyurethane molecular chain and the imine groups (-NH) in polyaniline form strong hydrogen bonds, which not only enhance the adhesion of polyaniline to the polyurethane surface but also promote the uniform deposition of the polyaniline layer. Combined with surface modification of sulfonic acid groups, a dense and continuous polyaniline shell can be formed. By combining polyaniline with a variety of thermoplastic materials, the microcapsules not only exhibit excellent stability but also have a wider range of applications.
[0030] By adding a certain amount of isooctyl acrylate to the photosensitive core material, the viscosity of the reaction system is reduced, ensuring that the highly active -NCO group in IPDI fully reacts with the hydroxyl group, preventing the viscosity of the polyurethane oligomer from being too high and affecting the repair effect. BRIEF DESCRIPTION OF THE DRAWINGS
[0031] Figure 1 Schematic diagram of the preparation process;
[0032] Figure 2 is the morphology of the microcapsules;
[0033] Figure 3 is the particle size distribution of microcapsules;
[0034] Figure 4 is the light absorbance test result of the microcapsules;
[0035] Figure 5 is the temperature change of microcapsules under infrared light irradiation;
[0036] Figure 6 The broken state of microcapsules after being irradiated by ultraviolet light;
[0037] Figure 7 This is a statistical chart showing the changes in the content of microcapsule core material. DETAILED DESCRIPTION
[0038] The present invention is described in further detail below with reference to the accompanying drawings:
[0039] Unless otherwise specified, the experimental methods used in the embodiments of the present invention are conventional methods.
[0040] The reagents and materials used in this example can be purchased conventionally. The quantitative experiments involved in the examples were repeated at least three times, and the results were averaged.
[0041] Source of raw materials:
[0042] TDI prepolymer L-75 was purchased from Bayer Technology, with a TDI monomer content of <5% and an NCO content of 13.3 ± 0.4%;
[0043] Amphiphilic TiO2 was nanoscale and purchased from MacLean Biotechnology, with a particle size of 60 nm, CAS: 13463-67-7;
[0044] Gum arabic, powder, pharmaceutical grade, was purchased from Aladdin Biotech;
[0045] E51 epoxy resin: purchased from Suzhou Qicaishi Composite Materials, with an epoxy equivalent weight of 185-200 g / eq;
[0046] Polyetheramine: purchased from Kunshan Lvxun Chemical, with an amine value (KOH / g) of 380-470 mg.
[0047] Example 1
[0048] First, isophorone diisocyanate IPDI is reacted with hydroxyethyl methacrylate HEMA to generate an active monomer, as shown in the following process: Figure 1 (1) As shown. IPDI, HEMA, 2-ethylhexyl acrylate, and butyl ditin dilaurate (DBTDL) were weighed and added to a three-necked flask, wherein the molar mass ratio of IPDI:HEMA:2-EHA was 1:1:1. DBTDL was used as a catalyst, and the added mass was 0.01 g per 50 g of core material. The mixture was heated in a water bath at 60°C and stirred for more than 12 h. Subsequently, the photoinitiator 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) was added and stirred evenly to obtain a photosensitive core material, wherein the molar ratio of TPO to HEMA was TPO:HEMA = 0.02:1.
[0049] Secondly, microcapsules were obtained by interfacial polymerization, as shown in the following process: Figure 1 (2) As shown. 4.5 g of TDI prepolymer L-75, 13.5 g of photosensitive core material, 8 g of chlorobenzene PhCl, and 1 g of amphiphilic TiO2 were added to a beaker and mixed evenly as the oil phase. 8 g of gum arabic GA was added to 100 mL of deionized water and stirred thoroughly at 55 °C as the aqueous phase. The oil phase was used as the dispersed phase and the aqueous phase as the continuous phase to obtain an O / W emulsion by microfluidics. Finally, 3.5 g of 1,4-butanediol BDO was added to the above emulsion, heated in a water bath at 65 °C and slowly stirred for 1 h, filtered, and dried to obtain TiO2@polyurethane photosensitive microcapsules.
[0050] Finally, high-stability self-repairing microcapsules with photothermal effect were prepared by in situ polymerization. Figure 1 (3) As shown. 1.0 g of sodium dodecylbenzenesulfonate (SDBS) was added to a three-necked flask filled with 100 mL of deionized water. A mechanical stirrer was used to stir at 200 rpm at room temperature for 1 h to ensure that SDBS was fully hydrolyzed. Subsequently, 10 g of TiO2@polyurethane microcapsules were added. The mixture was heated in a water bath at 40 °C and stirred at 100 rpm for 2 h to allow negatively charged sulfonate ions (SO3 -), filtered, and dried to obtain anion-attached microcapsules. Next, 0.93 g of aniline (AN) and 100 mL of 1 mol / L hydrochloric acid were added to a three-necked flask and stirred at 200 rpm for 6 h at room temperature to form an aniline acid solution. The anion-attached microcapsules were then added to the aniline acid solution, with 0.01 mol of aniline added per 10 g of microcapsules. Finally, 2.28 g of APS, 0.05 g of CoSO4·7H2O, and 50 mL of 1 mol / L hydrochloric acid were added to a beaker and stirred at 300 rpm for 1 h. After the solid was completely dissolved in the hydrochloric acid, the solution was added to the three-necked flask and heated in a water bath at 40°C with stirring at 200 rpm for 24 h. The mixture was filtered, washed, and dried to obtain highly stable self-healing microcapsules with photothermal effects.
[0051] Comparative Example 1
[0052] The difference between this comparative example and Example 1 is that only TiO2@polyurethane photosensitive microcapsules were prepared without subsequent aniline coating.
[0053] Comparative Example 2
[0054] The difference between this comparative example and Example 1 is that amphiphilic TiO2 is not added during the preparation process.
[0055] The microcapsules obtained in Example 1 and Comparative Example 1 were tested using SEM, and the results were as follows: Figure 2 As shown in (a). As can be seen in the figure, the surface of the TiO2@polyurethane photosensitive microcapsules obtained in Comparative Example 1 is relatively smooth, and the morphology of the high-stability self-repairing microcapsules with photothermal effect obtained in Example 1 is as follows Figure 2 As shown in (b), due to the in-situ deposition of PANI, the high stability self-healing microcapsules with photothermal effect are rougher. The particle size distribution analysis results are shown in Figure 3 As shown in Figure 4, the particle size of the highly stable self-healing microcapsules with photothermal effect is mainly concentrated between 190 and 220 μm, with an average particle size of 210.9 μm. Light absorbance tests were conducted on the TiO2@polyurethane photosensitive microcapsules and the highly stable self-healing microcapsules with photothermal effect, with the results shown in Figure 4. As can be seen from the figure, the prepared highly stable self-healing microcapsules with photothermal effect have excellent light absorbance across the entire wavelength range of 250-1400 nm, endowing the microcapsule shell with excellent UV light shielding and photothermal conversion capabilities, thereby ensuring the stability of the photosensitive core material and the multifunctionality of the microcapsules themselves.
[0056] In order to verify the photothermal conversion ability of the prepared high-stability self-healing microcapsules with photothermal effect, E51 epoxy resin and polyetheramine curing agent were evenly mixed in a mass ratio of 10:3, and 2wt% of high-stability self-healing microcapsules with photothermal effect were added. After ultrasonic dispersion, vacuum degassing was carried out, and the mixture was poured into a specific mold and cured at 50°C for 24 hours.
[0057] Pass 808 nm, light intensity 8.57 w / cm 2 When the composite material sample was irradiated with an infrared laser, the material heated up to 106.4 °C within 40 s, proving that the prepared high-stability self-healing microcapsules with photothermal effect had good photothermal conversion ability.
[0058] In order to verify the UV shielding ability of the highly stable self-repairing microcapsules with photothermal effect, a UV light with a wavelength of 365 nm and an UV intensity of 1700 mW / cm 2 The microcapsules obtained in Example 1 and Comparative Example 2 were irradiated with an ultraviolet lamp for 60 s, and then crushed with a cover glass and observed under an optical microscope. The results are as follows: Figure 6 As shown in (a) and (b), it can be clearly seen that the broken microcapsules of Example 1 still have the repair agent flowing out, while the core material of the microcapsules of Comparative Example 2 has already solidified, proving that the high-stability self-healing microcapsules with photothermal effect prepared in this work have good UV shielding properties.
[0059] TiO2@polyurethane microcapsules (Comparative Example 1) and high-stability self-repairing microcapsules with photothermal effect (Example 1) of equal mass were placed under natural light for 60 days. A portion of each was taken every 15 days to measure the core material content of the microcapsules by extraction method. The specific method was as follows: the dried microcapsules were placed on an electronic balance to obtain their initial mass, and then they were placed in a mortar and ground to completely break them. The broken microcapsules were washed with acetone, filtered and dried, and then the remaining mass was measured. The core material content percentage was obtained by (initial mass-remaining mass) / initial mass. The changes in the core material content ratio of the two microcapsules are shown in Figure 2. Figure 7 As shown, the core material loss of the high-stability self-repairing microcapsules with photothermal effect (Example 1) is significantly less than that of the TiO2@polyurethane microcapsules (Comparative Example 1), which proves that the prepared microcapsules have high stability.
[0060] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.
[0061] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.
Claims
1. A method for preparing high-stability self-repairing microcapsules with photothermal effect, characterized in that: The steps include: S1: diisocyanate, hydroxyl acrylate monomer, and isooctyl acrylate are mixed, reacted and polymerized under the action of a catalyst, and then a photoinitiator is added to the mixture to obtain a photosensitive core material; S2: adding TDI prepolymer, the photosensitive core material, and amphiphilic TiO2 to an organic solvent and mixing to obtain an oil phase; mixing an emulsifier with water to obtain an aqueous phase, and using the oil phase as a dispersed phase and the aqueous phase as a continuous phase to obtain an oil-in-water emulsion; mixing the oil-in-water emulsion with a small molecule polyol, performing an addition reaction, filtering, and drying to obtain TiO2@polyurethane photosensitive microcapsules; S3: dissolving an anionic surfactant in water, adding the TiO2@polyurethane photosensitive microcapsules to react at 40-50°C, and then filtering and drying to obtain anion-attached microcapsules; in situ polymerizing aniline on the surface of the anion-attached microcapsules, washing and drying to obtain the high-stability self-healing microcapsules with photothermal effect.
2. The method for preparing high-stability self-repairing microcapsules with photothermal effect according to claim 1, characterized in that: The molar ratio of the diisocyanate, the hydroxyl acrylate monomer and the isooctyl acrylate is 1:1:(0.75-1.5).
3. The method for preparing high-stability self-repairing microcapsules with photothermal effect according to claim 1, characterized in that: The reaction polymerization conditions described in S1 include: reaction at 55-65°C for 12-24 hours.
4. The method for preparing high-stability self-repairing microcapsules with photothermal effect according to claim 1, characterized in that: The diisocyanate includes isophorone diisocyanate; the hydroxy acrylate monomer includes one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate and hydroxyethyl acrylate.
5. The method for preparing high-stability self-repairing microcapsules with photothermal effect according to claim 1, characterized in that: The amount ratio of the photoinitiator added to the hydroxy acrylate monomer added is (0.01-0.03):
1.
6. The method for preparing high-stability self-repairing microcapsules with photothermal effect according to claim 1, characterized in that: In the oil phase, the mass ratio of TDI prepolymer, photosensitive core material and amphiphilic TiO2 is 1:(2.5-4):(0.1-0.3).
7. The method for preparing high-stability self-repairing microcapsules with photothermal effect according to claim 1, characterized in that: In S2, the conditions of the addition reaction include: reaction at 65-70° C. for 0.5-2 h; and the small molecule polyol includes 1,4-butanediol.
8. The method for preparing high-stability self-repairing microcapsules with photothermal effect according to claim 1, characterized in that: In S3, the ratio of the amount of aniline to the mass of the anion-attached microcapsules is (0.01-0.02) mol:10 g.
9. A high-stability self-repairing microcapsule with photothermal effect prepared according to the method according to any one of claims 1 to 8.
10. Use of the highly stable self-repairing microcapsules with photothermal effect as claimed in claim 9 in composite materials.