Mesoporous silica-cinnamomum camphora fruit anthocyanin composite material as well as preparation method and application thereof
By using a composite material of camphor fruit anthocyanins loaded with mesoporous silica, the problem of easy degradation of camphor fruit anthocyanins under light exposure was solved, thereby improving the lightfastness and color stability of wood veneers.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NANJING FORESTRY UNIV
- Filing Date
- 2026-02-11
- Publication Date
- 2026-05-12
AI Technical Summary
The anthocyanins in camphor fruit are easily degraded under light, resulting in poor lightfastness in wood staining and limiting their application in outdoor wood products.
Mesoporous silica was used as a carrier to extract camphor fruit anthocyanins through a eutectic solvent. The camphor fruit anthocyanins were then loaded onto the surface and pores of the mesoporous silica and combined with a temperature-dependent adsorption loading reaction to form a mesoporous silica-camphor fruit anthocyanin composite material.
It significantly improves the stability and durability of anthocyanins in camphor fruit, and enhances the lightfastness and color stability of wood veneers.
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Figure CN122011840A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of functional composite materials and wood dyeing, and specifically to a composite material prepared by efficiently extracting anthocyanins from camphor fruit using a low eutectic solvent and stabilizing them with mesoporous silica as a carrier, as well as its application. This material can improve the lightfastness and color stability of wood veneers. Background Technology
[0002] With the increasing demand for natural pigments and environmentally friendly materials, the wood dyeing industry is also seeking greener and more efficient solutions. Developing functional materials with good UV protection has become a hot topic. Naphthoquinone and anthraquinone natural dyes, such as those extracted from plants like alkanet root, turmeric, madder root, henna, and mulberry, provide good UV protection for fabrics and can be used to make UV-protective products.
[0003] Studies have shown that the main components of camphor fruit anthocyanins are paeonol-3-arabinoside, paeonol-3-xyloside, and paeonol-3-glucoside, or their derivatives. These substances also possess certain UV-resistant properties. However, camphor fruit anthocyanins are easily degraded under light and other conditions, resulting in poor lightfastness in wood staining and limiting their application in outdoor wood products. Therefore, improving the stability and durability of camphor fruit anthocyanins has become a key issue in their application in wood staining.
[0004] Mesoporous silica (MSNs) are considered ideal carrier materials due to their high specific surface area, ordered pore structure, and excellent UV shielding properties. Therefore, developing a camphor fruit anthocyanin composite material based on mesoporous silica as a carrier to improve the lightfastness and color stability of anthocyanins on wood surfaces is of great significance. Summary of the Invention
[0005] In view of this, the present invention provides a mesoporous silica-camphor fruit anthocyanin composite material, its preparation method and application. The mesoporous silica-camphor fruit anthocyanin composite material provided by the present invention provides a basis for the staining of wood veneer, improving the light fastness and performance of wood veneer.
[0006] Technical solution: In order to achieve the above-mentioned objective, the present invention provides a mesoporous silica-camphor fruit anthocyanin composite material, comprising mesoporous silica and camphor fruit anthocyanins loaded on the surface and pores of the mesoporous silica; the mesoporous silica has a high specific surface area, an ordered pore structure and good ultraviolet shielding performance.
[0007] On the other hand, the present invention provides a method for preparing a mesoporous silica-camphor fruit anthocyanin composite material, comprising the following steps:
[0008] Anthocyanins were extracted from camphor fruit using a eutectic solvent as the extractant to obtain camphor fruit anthocyanin extract. The mesoporous silica carrier was mixed with the camphor fruit anthocyanin extract and subjected to an adsorption loading reaction. After the reaction was completed, the mixture was separated, washed, and dried to obtain the composite material. The eutectic solvent was composed of choline chloride and citric acid.
[0009] Furthermore, the molar ratio of choline chloride to citric acid is 1:3~4.
[0010] Furthermore, the water content of the eutectic solvent is 50% to 70%; preferably, the water content of the eutectic solvent is 60%.
[0011] Further, the ratio of camphor fruit to eutectic solvent is 0.07–0.08 g / mL. Preferably, the ratio of camphor fruit anthocyanin extract to solvent is 1:20 g / mL.
[0012] Furthermore, in the process of extracting anthocyanins from camphor fruit, the extraction temperature is 55–70°C and the extraction time is 60–90 min. Preferably, the extraction temperature is 62°C.
[0013] Preferably, the extraction time is 75 min.
[0014] Furthermore, the adsorption loading reaction is carried out under variable temperature conditions, with the reaction temperature varying between 40–60°C and 4°C, and the total loading time being 50–70 min. Specifically, the loading time is 20–40 min at 40–60°C and 30 min at 4°C.
[0015] Preferably, the total load time is 60 min, including 30 min of treatment at 50°C.
[0016] Preferably, the eutectic solvent has a water content of 60%.
[0017] Furthermore, the mass-to-volume ratio of the mesoporous silica carrier to the anthocyanin extract is 1:12 to 1:15 g / mL.
[0018] Preferably, the mesoporous silica has a purity of 98%, is industrial grade, has a particle size of 1000 nm, and a pore size of 10 nm.
[0019] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: the mesoporous silica anthocyanin loading rate provided by the present invention is more than 22%. Attached Figure Description
[0020] Figure 1The effect of radiation time on the color difference of dyed veneers is given, where a is the effect on the total color difference value ΔE, b is the effect on the lightness difference value ΔL, c is the effect on the chromaticity difference value Δa, and d is the effect on the chromaticity difference value Δb.
[0021] Figure 2 The effect of radiation temperature on the color difference of dyed veneer is given, where a is the effect on the total color difference value ΔE, b is the effect on the lightness difference value ΔL, c is the effect on the chromaticity difference value Δa, and d is the effect on the chromaticity difference value Δb.
[0022] Figure 3 The effect of radiation intensity on the color difference of dyed veneers is given by: a represents the effect on the total color difference ΔE, b represents the effect on the lightness difference ΔL, c represents the effect on the chromaticity difference Δa, and d represents the effect on the chromaticity difference Δb. Detailed Implementation
[0023] This invention provides a mesoporous silica-camphor fruit anthocyanin composite material, comprising mesoporous silica and camphor fruit anthocyanins loaded on the surface and pores of the mesoporous silica; the mesoporous silica has a high specific surface area, an ordered pore structure, and good ultraviolet shielding performance.
[0024] Example 1
[0025] Choline chloride and citric acid were mixed in a molar ratio of 1:3, and deionized water was added to prepare a eutectic solvent with a water content of 60%. Dried and pulverized camphor fruit raw material was added to this eutectic solvent at a material-to-liquid ratio of 1:20 g / mL, and ultrasonic-assisted extraction was performed at 62℃ for 75 minutes. After extraction, the crude extract was centrifuged, the supernatant was collected, and purified using macroporous resin to obtain a purified camphor fruit anthocyanin extract stock solution. This stock solution was diluted with deionized water or buffer solution to an anthocyanin concentration of 1.8 mg / mL as needed, and set aside. 1.4 g of mesoporous silica (particle size 1000 nm, pore size 10 nm) was weighed into 20 mL of a 1.8 mg / mL camphor fruit anthocyanin extract; the anthocyanin extract was obtained by extraction in a eutectic solvent (choline chloride:citric acid molar ratio = 1:3, water content 60%).
[0026] The mixture was stirred in a 50℃ water bath for 30 minutes, which was recorded as the first temperature change treatment. It was then transferred to a 4℃ environment and allowed to stand for 30 minutes, which was the second temperature change treatment. After the reaction was complete, the solid product was separated by centrifugation at 10000 r / min for 10 minutes, washed twice with deionized water, and then vacuum dried at 45℃ for 12 hours to obtain the mesoporous silica-camphor fruit anthocyanin composite material. The anthocyanin loading rate was determined to be 24.89%.
[0027] Example 2
[0028] The only difference from Example 1 is that the total adsorption loading reaction time was 70 minutes (40 minutes at 50°C and 30 minutes at 4°C). A composite material with an anthocyanin loading of 23.50% was ultimately obtained.
[0029] Example 3
[0030] The only difference from Example 1 is that the amount of mesoporous silica added is 1.6 g. A composite material with an anthocyanin loading of 22.10% was finally obtained.
[0031] Example 4
[0032] The only difference from Example 1 is that the water content of the anthocyanin extract is 50%, the ratio of camphor fruit to eutectic solvent is 1:15 g / mL, the extraction temperature is 55℃ during the extraction of anthocyanins from camphor fruit, and the total adsorption loading reaction time is 50 minutes (20 minutes at 40℃ and 30 minutes at 4℃).
[0033] Example 5
[0034] The only difference from Example 1 is that the water content of the anthocyanin extract is 70%, the ratio of camphor fruit to eutectic solvent is 1:25 g / mL, the extraction temperature is 70℃ during the extraction of anthocyanins from camphor fruit, and the total adsorption loading reaction time is 50 minutes (20 minutes at 40℃ and 30 minutes at 4℃).
[0035] Comparative Example 1
[0036] The only difference from Example 1 is that the adsorption loading reaction was carried out under isothermal conditions, with stirring at 25°C for 60 minutes. The final result was a composite material with an anthocyanin loading of 18.60%.
[0037] Comparative Example 2
[0038] The only difference from Example 1 is that the mass-to-volume ratio of mesoporous silica support to anthocyanin extract is 1:10 g / mL (i.e., 2.0 g MSNs added to 20 mL of solution). A composite material with an anthocyanin loading of 19.85% was ultimately obtained.
[0039] Comparative Example 3
[0040] The only difference from Example 3 is that the amount of mesoporous silica added is 1.6 g. A composite material with an anthocyanin loading of 22.10% was finally obtained.
[0041] Table 1. Anthocyanin loading rate under different process conditions
[0042]
[0043] As shown in Table 1, the optimized preparation process provided by this invention (Example 1) achieves the highest anthocyanin loading rate. Compared with the unoptimized isothermal process (Comparative Example 1) or the inappropriate material ratio (Comparative Example 2), the loading rate is significantly improved, fully demonstrating the excellent effect of the method of this invention in improving loading efficiency.
[0044] Example 6
[0045] To verify the application effect of the composite material of this invention in the field of wood dyeing, a single-factor test on the sun resistance of wood veneer dyed with anthocyanin composite dye was conducted. The test materials were all cedar veneers and oak veneers with a moisture content of 12% and a size of 40 mm × 40 mm × 3 mm (length × width × thickness), without defects.
[0046] The mesoporous silica-camphor fruit anthocyanin complex material obtained in Example 1 was dissolved in an ethanol-water mixture (volume ratio 1:1) to prepare a dye solution with a concentration of 1.0 mg / mL. The control group used an extract of camphor fruit anthocyanins at the same concentration.
[0047] Several oak and cedar veneers were immersed in two different dye solutions for 30 min each, then removed and dried in hot air at 60 ℃ for 20 min to obtain four groups of dyed samples, named Group A (oak stained with mesoporous silica-camphor fruit anthocyanin complex), Group B (cedar stained with mesoporous silica-camphor fruit anthocyanin complex), Group C (oak stained with camphor fruit anthocyanin), and Group D (cedar stained with camphor fruit anthocyanin), with three pieces in each group.
[0048] Each group of samples was placed in a UV aging chamber and subjected to a single-factor test for lightfastness using a xenon lamp source. Radiation time, radiation temperature, and radiation intensity were considered as factors. The color retention rate and lightfastness of the treated samples were measured, and the test results are as follows: Figure 1 , Figure 2 , Figure 3 As shown.
[0049] (1) Effect of radiation time on the light fastness of oak and cedar veneers
[0050] The changes in lightness difference ΔL*, chroma difference Δa*, Δb*, and total color difference (ΔE*) of oak and cedar veneers stained with camphor fruit anthocyanins and mesoporous silica-camphor fruit anthocyanin complex after xenon light irradiation for 0–120 h are shown in the figure. Figure 1 As irradiation time increased, ΔE* for all samples showed a trend of first increasing sharply and then leveling off slightly.
[0051] Under the same irradiation time, the color changes (ΔE*, ΔL*, Δa*, Δb*) of the mesoporous silica-camphor fruit anthocyanin-stained wood veneer were consistently less than those of the camphor fruit anthocyanin-stained wood veneer, indicating that the addition of MSNs has a certain improvement in UV resistance.
[0052] (2) Effect of radiation temperature on the light fastness of oak and cedar veneers
[0053] The changes in lightness difference ΔL*, chroma difference Δa*, Δb*, and total color difference (ΔE*) of oak and cedar veneers stained with camphor fruit anthocyanins and mesoporous silica-camphor fruit anthocyanins after xenon light irradiation at different temperatures (30-70 ℃) are shown in the figure. Figure 2 .
[0054] As the radiation temperature increased, the ΔE* value of all samples showed an upward trend, indicating that the total color difference increased.
[0055] Among them, the ΔE* value of cedarwood stained with camphor fruit anthocyanins showed the largest increase, especially at temperatures exceeding 60℃. With increasing radiant temperature, the Δa* and Δb* values of cedarwood stained with camphor fruit anthocyanins and cedarwood stained with mesoporous silica-camphor fruit anthocyanin complex showed increasing and decreasing trends, respectively, indicating a greater shift in color towards green and yellow. The Δa* and Δb* values of oak stained with camphor fruit anthocyanins and oak stained with mesoporous silica-camphor fruit anthocyanin complex changed less at low temperatures, but showed a greater trend at high temperatures (60℃ and above).
[0056] (3) Effect of radiation intensity on the light fastness of oak and cedar veneers
[0057] The changes in lightness difference ΔL*, chromaticity difference Δa*, Δb*, and total chromaticity difference ΔE* of oak and cedar veneers stained with camphor fruit anthocyanins and mesoporous silica-camphor fruit anthocyanins after xenon light irradiation at different intensities (0-2.0 W / m·nm⁻¹) are shown in the figure. Figure 3 .
[0058] As shown in the figure, with the increase of radiation intensity, the ΔE* of the samples all showed a trend of first increasing significantly and then stabilizing. This indicates that radiation intensity has a significant impact on the color stability of stained wood, and when the radiation intensity reaches a certain value (2.0 W / m·nm⁻¹), ΔE* no longer changes significantly. Compared with stained wood veneer alone, the mesoporous silica-camphor fruit anthocyanin-stained wood veneer has a certain improvement in UV resistance. This shows that the addition of mesoporous silica has a certain effect on the UV resistance of wood, especially on cedar veneer, where it has a better UV resistance effect.
[0059] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A mesoporous silica-camphor fruit anthocyanin composite material, characterized in that, The composite material includes mesoporous silica and camphor fruit anthocyanins loaded on the surface and within the pores of the mesoporous silica.
2. A method for preparing a mesoporous silica-camphor fruit anthocyanin composite material, characterized in that, Includes the following steps: Anthocyanins were extracted from camphor fruit using a eutectic solvent as the extractant to obtain camphor fruit anthocyanin extract. The mesoporous silica carrier was mixed with the camphor fruit anthocyanin extract and subjected to an adsorption loading reaction. After the reaction was completed, the mixture was separated, washed, and dried to obtain the composite material. The eutectic solvent was composed of choline chloride and citric acid.
3. The preparation method of the mesoporous silica-camphor fruit anthocyanin composite material according to claim 2, characterized in that, In the eutectic solvent, the molar ratio of choline chloride to citric acid is 1:3~4.
4. The preparation method of the mesoporous silica-camphor fruit anthocyanin composite material according to claim 2, characterized in that, The water content of the eutectic solvent is 50% to 70%.
5. The preparation method of the mesoporous silica-camphor fruit anthocyanin composite material according to claim 2, characterized in that, The ratio of camphor fruit to eutectic solvent is 1:15 to 1:25 g / mL.
6. The method for preparing the mesoporous silica-camphor fruit anthocyanin composite material according to claim 2, characterized in that, During the extraction of anthocyanins from camphor fruit, the extraction temperature is 55–70℃ and the extraction time is 60–90 min.
7. The method for preparing the mesoporous silica-camphor fruit anthocyanin composite material according to claim 2, characterized in that, The adsorption loading reaction was carried out under variable temperature conditions, with the reaction temperature varying between 40–60°C and 4°C, and the total loading time being 50–70 min.
8. The method for preparing the mesoporous silica-camphor fruit anthocyanin composite material according to claim 2, characterized in that, The mass-to-volume ratio of the mesoporous silica carrier to the anthocyanin extract is 0.07–0.08 g / mL.
9. The application of the mesoporous silica-camphor fruit anthocyanin composite material according to claim 1 in wood staining.