High-biological-activity lignin and preparation method thereof
阅读说明：本技术 一种高生物活性木质素及其制备方法 (High-biological-activity lignin and preparation method thereof ) 是由 毛志慧 齐国闯 马丕明 杨伟军 于 2021-08-06 设计创作，主要内容包括：本发明提供了一种以纳米木质素(LNP)为原料制备胺化改性高生物活性木质素的方法。所述原料中纳米木质素10～50份,胺基化合物10～50份,醛基化合物10～50份,二氧化钛(TiO-(2))0.1～2份。该方法将木质素和胺基化合物按一定比例混合,常温下磁力搅拌,然后将醛基化合物与TiO-(2)/水分散以滴加的方式混合均匀,在60～100℃和惰性气体保护等条件下进行曼尼希反应；本方法工艺简单、制备周期短、产率高。本发明使用木质素制备得到的胺化改性高活性木质素,与商业抗氧化剂相比,其清除自由基性能得到显著提升,且兼具优异的协同紫外屏蔽性能和抗菌活性,可应用于在化妆品、个人护理用品、生物制药、聚合物复合材料等领域。(The invention provides a method for preparing amination modified high-bioactivity lignin by taking nano Lignin (LNP) as a raw material. The raw materials comprise 10-50 parts of nano lignin, 10-50 parts of amino compounds, 10-50 parts of aldehyde compounds and titanium dioxide (TiO) 2 ) 0.1-2 parts. The method comprises mixing lignin and amino compound at a certain ratio, magnetically stirring at room temperature, and mixing aldehyde compound with TiO 2 Uniformly mixing the water dispersion in a dropwise manner, and carrying out Mannich reaction at the temperature of 60-100 ℃ under the protection of inert gas and the like; the method has simple process, short preparation period and high yield. Compared with commercial antioxidants, the aminated modified high-activity lignin prepared from lignin has the advantages that the performance of scavenging free radicals is remarkably improved, and the aminated modified high-activity lignin has excellent synergistic ultraviolet shielding performance and antibacterial activity, and can be applied to the fields of cosmetics, personal care products, biopharmaceuticals, polymer composite materials and the like.)
1. The method for preparing the modified lignin is characterized in that the method is implemented by an amine compound, an aldehyde compound and TiO2And modifying the nano lignin.
2. The method according to claim 1, wherein the components in the modification process comprise, by weight, 50-100 parts of nano lignin, 10-50 parts of an amino compound, 10-50 parts of an aldehyde compound, and 0.1-2 parts of TiO2。
3. The method according to claim 1, wherein the method comprises the steps of uniformly mixing 0.1-5 w/v% of nano lignin dispersion liquid and an amine compound, and then adding an aldehyde compound and TiO2And (3) uniformly mixing the dispersion liquid, reacting under the protection of inert gas, and dialyzing after the reaction is finished to obtain the modified lignin.
4. The method of claim 1, wherein the nano lignin is one or more of alkali lignin, organosolv lignin, lignosulfonate, and kraft lignin.
5. The method of claim 1, wherein the aldehyde is one of formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, furfural, dialdehyde, and unsaturated aldehyde.
6. The method of claim 1, wherein the amine is one of a linear or branched alkylamine, a cyclic amine, a polyamine, a hydroxyalkylamine, and an amino acid.
7. The method according to claim 3, wherein the aldehyde compound and TiO are slowly added dropwise at 60-100 ℃2And (3) dispersing the mixture.
8. The method according to any one of claims 1 to 7, wherein the amount of the aldehyde compound and the amine compound is 1:0.4 to 2.5 in terms of molar ratio of CHO to NH.
9. A modified lignin prepared by the method of any one of claims 1 to 8.
10. Use of a modified lignin according to claim 9 in the fields of cosmetics, personal care products, biopharmaceuticals, coatings, polymer composites.
Technical Field
The invention belongs to the field of environment-friendly natural high polymer materials, and relates to lignin with high oxidation resistance, broad-spectrum antibiosis and ultraviolet resistance and a preparation method thereof.
Background
With the improvement of quality of life, antioxidants play an increasingly important role in human dietary life. The addition of antioxidant functional substances such as dibutyl hydroxy toluene (BHT), tert-butyl p-hydroxy anisole (BHA), etc. can delay aging rate and promote health. Medical research shows that the primary generation of human chronic diseases is caused by the robbing of cell electrons, and free radicals enter a human body and then easily rob the cell electrons, so that the resistance of cells is reduced, the body is easily infected by germs, and even carcinogenic substances are formed. Therefore, the antioxidation and the elimination of free radicals are always the research hotspots at home and abroad.
With the increasing health awareness of people, the use of some natural antioxidants is gradually replacing commercial antioxidants, which is of great significance for reducing the cost and efficiently using the antioxidants. As a natural polyphenol polymer with a three-dimensional network structure, the lignin has quite diversified properties: such as oxidation resistance, antibiosis, innocuity, ultraviolet resistance, etc. However, currently most of the lignin is disposed of as industrial waste or fuel; and when the lignin is used as a natural antioxidant, the antioxidant and antibacterial activities of the lignin are low, and the ultraviolet shielding efficiency is not high enough. Therefore, the improvement of the comprehensive biological activity of the lignin has great significance for expanding the application of the lignin and promoting the sustainable utilization of resources. Documents Ind.Crops prod.2019,128, 177-185, ACS Sustainable chem.Eng.2018,6(2), 2591-doped 2595 and Ind.Crops prod.2017,95, 512-doped 520 respectively improve the oxidation resistance of lignin by depolymerization by a hydrothermal method, lacquer mold and ionic liquid modification, but the ultraviolet shielding performance and the antibacterial activity are not substantially improved; the document Green chem, 2020,22,6357-6371 reports that arginine, histidine and lysine are grafted onto the surface of lignin, so that the antibacterial activity of lignin is improved, the modified lignin product has selective antibacterial effect on gram-positive bacteria and gram-negative bacteria but does not have broad-spectrum antibacterial function, and the antioxidant capacity and ultraviolet shielding capacity of lignin are not substantially improved.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides a novel method for preparing lignin with excellent antioxidant, antibacterial and ultraviolet resistant functions by using a lignin two-step method. The invention can improve the specific surface area of lignin and increase antioxidant active groups. The prepared antioxidant nano lignin has excellent functions of antioxidation, synergistic broad-spectrum antibiosis, ultraviolet shielding and the like. The method has the advantages of simple synthesis process, easily obtained raw materials and environmental protection.
In order to achieve the purpose, the invention is realized by the following technical scheme:
the first object of the invention is a modified lignin and a preparation method thereof, which is characterized in that the modified lignin is prepared from raw materials comprising the following components:
in an embodiment of the present invention, the components in the modification process include, by weight, 50 to 100 parts of nano lignin, 10 to 50 parts of an amino compound, 10 to 50 parts of an aldehyde compound, and TiO20.1-2 parts.
In one embodiment of the invention, the modified lignin and the preparation method thereof are characterized in that 0.1-5 w/v% of nano lignin dispersion liquid and an amino compound are uniformly mixed according to a certain proportion, and then an aldehyde compound and TiO are added2And (3) uniformly mixing the dispersion liquid, reacting under the protection of inert gas, and dialyzing after the reaction is finished to obtain the modified lignin.
In one embodiment of the invention, the nano lignin is one or more of alkali lignin, organic solvent lignin, lignosulfonate and kraft lignin.
In one embodiment of the present invention, the aldehyde is one of formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, furfural, dialdehyde, and unsaturated aldehyde.
In one embodiment of the present invention, the number of carbons of the linear or branched alkylamine is 1 to 8.
In one embodiment of the present invention, the amine is one of linear or branched alkylamine, cyclic amine, polyamine, hydroxyalkylamine, and amino acid.
In one embodiment of the invention, the aldehyde compound and TiO are slowly dropped at 60-100 DEG C2And (3) dispersing the mixture.
In one embodiment of the invention, the nano lignin dispersion and TiO2The solvent of the dispersion is water. In one embodiment of the present invention, the TiO is2In an amount of0.1 to 2 portions
In one embodiment of the present invention, the dialysis time is 1 to 12 hours.
In one embodiment of the invention, the nano-lignin and amine-based compound are added to a bottle, N2As protective gas, slowly dripping aldehyde compound and TiO at 60-100 DEG C2And (3) carrying out Mannich reaction in a compounding way, and dialyzing after the reaction is finished for 1-12h to obtain the aminated modified lignin. The obtained product has excellent oxidation resistance, antibacterial and ultraviolet shielding functions
In one embodiment of the present invention, the Mannich reaction is carried out under heating, preferably under anhydrous conditions at 50 to 100 ℃.
In one embodiment of the present invention, the required amount of the aldehydes and amines is 1: 0.4-2.5 in terms of molar ratio of CHO to NH.
In one embodiment of the present invention, the aldehyde may be, but is not limited to, one of formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, furfural, dialdehyde (such as glutaraldehyde, glyoxal, etc.), unsaturated aldehyde (such as acrolein, crotonaldehyde, etc.).
In one embodiment of the present invention, the amine is one of linear or branched alkylamine, cyclic amine, polyamine (such as ethylenediamine, hexamethylenediamine, diethyltriamine, triethyltetramine, tetraethylpentamine, etc.), hydroxyalkyl amine (such as hydroxyethylprimary amine, dihydroxyethylamine, triethanolamine, aminoethylethanolamine, etc.), amino acid (such as lysine, sarcosine, glycine, iminodiacetic acid, tyrosine, aspartic acid, etc.).
In one embodiment of the present invention, the solvent may be at least one of water, acetone, Dimethylformamide (DMF), Dimethylacetamide (DMAC), Tetrahydrofuran (THF), and dioxane.
The invention also provides modified lignin by utilizing the method.
The second purpose of the invention is to provide the application of the modified lignin in the fields of cosmetics, personal care products, biomedicine, coatings and polymer composite materials.
Compared with the prior art, the invention has the following advantages and beneficial effects:
1. the lignin raw material provided by the invention is wide in source, renewable, environment-friendly and biodegradable, and low in cost. Meanwhile, the surface of the nano lignin is high in activity, and compared with a commercial antioxidant, the aminated modified nano lignin disclosed by the invention is more excellent in environmental friendliness; the antioxidant has excellent antioxidant performance, and the capacity of scavenging free radicals of Diphenyl Picryl Phenylhydrazine (DPPH) after 6 hours reaches 98.0%, and the effect is superior to that of a commercial antioxidant of dibutyl hydroxy toluene (BHT).
2. The aminated lignin is safe and nontoxic, has excellent antibacterial performance, and the antibacterial efficiency of gram-positive bacteria and gram-negative bacteria exceeds 50 percent and exceeds the antibacterial efficiency of lignin per se (less than 20 percent).
3. The T-LNP has a more excellent ultraviolet shielding function, and compared with lignin, the ultraviolet shielding performance is improved by more than 35%.
4. The modified T-LNP of the invention can be used in the fields of cosmetics, personal care products, biopharmaceuticals, polymer composites and the like.
Detailed Description
Although the present invention has been described in detail, the present invention is not limited thereto, and those skilled in the art can modify the principle of the present invention, and thus, various modifications made in accordance with the principle of the present invention should be understood to fall within the scope of the present invention.
And (3) testing antioxidant activity: preparing a sample to be detected into a 0.01g/mL aqueous solution, mixing 2.0mL of the 0.01g/mL solution with 2.0mL of a 50mg/L DPPH solution, carrying out free radical capture reaction for 1, 3 and 6 hours, detecting and fitting a peak area at 517nm by using an ultraviolet spectrophotometer, and calculating to obtain the intensity of the removed free radicals, wherein the peak area of a blank sample at 517nm is 22.5.
And (3) testing the bacteriostatic activity: preparing the obtained lignin sample to 1.0g/L concentration, mixing 10 μ L with 180 μ L bacterial suspension, and applying the mixture to the culture mediumIrradiating the agar plate with ultraviolet light at 37 deg.C for 3 hr, culturing in culture medium for 24 hr, observing and counting bacterial colony number, wherein the bacterial colony number of the lignin-free blank gram-positive bacteria (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli) is 1.5 × 107CFU/mL and 1.3X 107CFU/mL。
And (3) testing ultraviolet shielding performance: and fully mixing the obtained lignin sample with PVA (polyvinyl alcohol) in an aqueous solution, pouring to form a film, wherein the lignin content is 1.0%, the film thickness is 200 micrometers, testing the transparency (500nm) and the ultraviolet shielding performance (320nm) of the PVA composite material film by using an ultraviolet spectrophotometer, and the light transmittances of the pure PVA film at 500nm and 320nm are respectively 92% and 85%.
With respect to TiO2Dispersion liquid: 1.0g of TiO was taken2Dispersed in 100mL of water to prepare 0.01g/mL of TiO2The dispersion was prepared in one portion of 1.0mL of the dispersion.
Regarding the ZnO dispersion: 1.0g of ZnO was dispersed in 100mL of water to prepare a 0.01g/mL ZnO dispersion, and 1.0mL of the dispersion was used as one portion.
Example 1:
adding nano lignin (100 parts by mass, 0.01 g) and ethylenediamine (10 parts) into a reaction flask, N2As protective gas, formaldehyde (10 parts) and TiO are slowly added dropwise at 60 DEG C2Performing Mannich reaction on the dispersion (0.1 part) and dialyzing after 10h reaction to obtain aminated modified lignin, wherein the product is T-LNP1 for short, and the antioxidant activity, the antibacterial activity and the ultraviolet shielding performance of the aminated modified lignin are shown in the following tables 1, 2 and 3 respectively.
Example 2:
adding nano lignin (100 parts) and ethylenediamine (50 parts) into a reaction bottle, and adding N2As protective gas, formaldehyde (50 parts) and TiO were slowly added dropwise at 100 deg.C2Performing Mannich reaction on the dispersion (0.5 part) and dialyzing after 1h reaction to obtain aminated modified lignin, wherein the product is T-LNP2 for short, and the antioxidant activity, the antibacterial activity and the ultraviolet shielding performance of the aminated modified lignin are shown in the following tables 1, 2 and 3 respectively.
Example 3:
adding nano lignin (100 parts) and dihydroxyethylamine (50 parts) into a reaction flask, N2As protective gas, glutaraldehyde (50 parts) and TiO were slowly added dropwise at 100 ℃2And (3) carrying out Mannich reaction on the dispersion liquid (2 parts), and dialyzing after 1h of reaction to obtain aminated modified lignin, wherein a product is T-LNP3 for short, and the antioxidant activity, the antibacterial activity and the ultraviolet shielding performance of the aminated modified lignin are shown in the table 1 and the antibacterial activity and the ultraviolet shielding performance of the aminated modified lignin are shown in the table 2 and 3 respectively.
Example 4:
adding nano lignin (100 parts) and lysine (10 parts) into a reaction bottle, and adding N2As protective gas, formaldehyde (10 parts) and TiO are slowly added dropwise at 60 DEG C2Performing Mannich reaction on the dispersion (0.5 part), dialyzing after 12h reaction to obtain aminated modified lignin, wherein a product is T-LNP4 for short, and the antioxidant activity, the antibacterial activity and the ultraviolet shielding performance of the aminated modified lignin are shown in the table 1, the antibacterial activity and the ultraviolet shielding performance of the aminated modified lignin are shown in the table 2 and 3 respectively.
Example 5:
adding nano lignin (80 parts) and hexamethylene diamine (20 parts) into a reaction bottle, and adding N2As protective gas, furfural (20 parts) and TiO were slowly dropped at 70 deg.C2And (3) carrying out Mannich reaction on the dispersion liquid (1 part), and dialyzing after 8h reaction to obtain aminated modified lignin, namely a product T-LNP5 for short, wherein the antioxidant activity is shown in Table 1, the antibacterial activity is shown in Table 2, and the ultraviolet shielding property is shown in Table 3.
Example 6:
adding nano lignin (50 parts) and aspartic acid (50 parts) into a reaction bottle, N2As protective gas, acrolein (50 parts) and TiO were slowly added dropwise at 100 ℃2And (3) carrying out Mannich reaction on the dispersion liquid (2 parts), and dialyzing after 6h of reaction to obtain aminated modified lignin, wherein a product is T-LNP6 for short, and the antioxidant activity, the antibacterial activity and the ultraviolet shielding performance of the aminated modified lignin are shown in the table 1, the antibacterial activity and the ultraviolet shielding performance are shown in the table 2 and 3.
Example 7:
adding nano lignin (100 parts) and aspartic acid (25 parts) into a reaction bottle, N2As protective gas, acrolein (25 parts) and TiO were slowly added dropwise at 65 ℃2Dispersion (1 part) was subjected to MannichAnd (3) after the reaction is finished for 12 hours, dialyzing to obtain aminated modified lignin, wherein a product is T-LNP7 for short, the antioxidant activity of the aminated modified lignin is shown in a table 1, the antibacterial activity of the aminated modified lignin is shown in a table 2, and the ultraviolet shielding performance of the aminated modified lignin is shown in a table 3.
Example 8:
adding nano lignin (100 parts) and tyrosine (25 parts) into a reaction bottle, N2As protective gas, formaldehyde (25 parts) and TiO were slowly added dropwise at 100 deg.C2And (3) carrying out Mannich reaction on the dispersion (1.5 parts), and dialyzing after 2h of reaction to obtain aminated modified lignin, wherein a product is T-LNP8 for short, and the antioxidant activity, the antibacterial activity and the ultraviolet shielding performance of the aminated modified lignin are shown in the table 1, the antibacterial activity and the ultraviolet shielding performance of the aminated modified lignin are shown in the table 2 and 3 respectively.
Comparative example 1:
100 parts of common lignin is taken, acidolysis nanocrystallization and amination modification treatment are not carried out on the common lignin, only the raw material is ground, and the micrometer lignin is obtained by a 120-mesh screen, wherein the antioxidant activity, the bacteriostatic activity and the ultraviolet shielding performance of the micrometer lignin are shown in the table 1 and the table 2 respectively.
Comparative example 2:
adding nano lignin (100 parts, 0.01g in one part) into a reaction bottle, and slowly dripping TiO at 60 DEG C2After the completion of the dispersion (0.1 part), dialysis was performed to obtain comparative sample 2, whose antioxidant activity, antibacterial activity and ultraviolet shielding properties are shown in tables 1, 2 and 3, respectively.
Comparative example 3:
referring to comparative example 2, TiO2The dispersion was replaced with an equivalent amount of ZnO dispersion, and the other was not changed to prepare a comparative sample 3, whose antioxidant activity is shown in table 1, antibacterial activity is shown in table 2, and ultraviolet shielding property is shown in table 3.
Comparative example 4:
100 parts of a commercial antioxidant BHT (dibutylhydroxytoluene) purchased from Merlan corporation was used as a comparative sample 4, and its antioxidant activity, bacteriostatic activity and ultraviolet shielding performance are shown in tables 1, 2 and 3, respectively.
Comparative example 5:
the aminated modified lignin was prepared by taking 100 parts of ordinary lignin and preparing the aminated modified lignin under the conditions of example 1, and comparative sample 5 was prepared, the antioxidant activity of which is shown in table 1, the bacteriostatic activity of which is shown in table 2, and the ultraviolet shielding property of which is shown in table 3.
Comparative example 6:
referring to example 1, TiO2The dispersion liquid is changed into an equivalent ZnO dispersion liquid, the other conditions are not changed, a comparison sample 6 is prepared, the antioxidant activity, the antibacterial activity and the ultraviolet shielding performance of the prepared aminated modified lignin are shown in the table 1 and the table 2 respectively.
Comparative example 7:
with reference to example 1, no TiO was added2Comparison sample 7 of aminated modified lignin was prepared, and its antioxidant activity, bacteriostatic activity and ultraviolet screening properties are shown in tables 1, 2 and 3, respectively.
TABLE 1 comparison table of antioxidant activity of each sample
Description of the drawings: antioxidant efficiency Q1(22.5-x)/22.5, wherein x represents the fitting area at 517nm of the ultraviolet spectrophotometer at different times;
according to the above test results: compared with the comparative examples 1 and 2, the oxidation resistance of the examples 1-8 in different time periods is obviously improved; compared with the comparative example 3, the oxidation resistance of the examples 1-8 is even higher than that of a commercial antioxidant BHT after the radical capture reaction is carried out for 3 hours, because the content of phenolic hydroxyl groups of lignin can be increased through the Mannich reaction, and the generated amine groups enable the lignin to form more stable phenoxy free radicals, so that hydrogen protons can be separated from the lignin to react with DPPH radicals more easily, and the oxidation resistance is improved; nano-lignin is more active than micro-lignin because the specific surface area of small size lignin is increased and more phenolic hydroxyl groups are exposed. In contrast, comparative example 4, which did not treat lignin, had a small specific surface area, a low degree of amination reaction, and an antioxidant activity that was not as effective as the commercial antioxidant BHT.
TABLE 2 comparison table of bacteriostatic effect of each sample
Description of the drawings: bacteriostatic efficiency Q2(a-y)/a or (b-y)/b, wherein a is 1.5 × 107CFU/mL；b＝1.3×107CFU/mL, y represents the number of bacteria in different samples;
according to the above test results: compared with the comparative examples 1, 2, 3 and 4, the antibacterial efficiency of the examples 1 to 8 is obviously improved and exceeds 30 percent; compared with the comparative example 1, the nano lignin of the comparative example 2 has slightly improved bacteriostatic efficiency, the bacteriostatic efficiency of staphylococcus aureus is 20.0%, the bacteriostatic efficiency of escherichia coli is 13.8%, the antibacterial and antioxidant mechanisms of lignin are similar, namely the antioxidant performance is improved, the general antibacterial activity is improved to a certain extent, the nano lignin with small particle size can effectively inhibit the bacterial growth, BHT (example 3) also has certain antibacterial performance, the bacteriostatic efficiency of staphylococcus aureus is 24.0%, and the bacteriostatic efficiency of escherichia coli is 16.9%. Compared with comparative example 1, the amination modified lignin of comparative example 4 has obviously improved bacteriostatic efficiency, but is still at a lower level because the lignin used in comparative example 4 has large size and small specific surface area, so that amination reaction can not graft more amine groups on the lignin.
Also, in various embodiments, with TiO2The principle is that titanium dioxide decomposes bacteria under the action of photocatalysis to achieve an antibacterial effect, and aminated lignin and titanium dioxide show a synergistic antibacterial effect, for example, in example 6, the antibacterial efficiency of staphylococcus aureus of the prepared modified lignin reaches 93.3%, and the antibacterial efficiency of escherichia coli bacteria reaches 93.1%, which exceeds the antibacterial efficiency of all other samples. The experimental results show that the compound is reacted with TiO2The product obtained by Mannich reaction after compounding shows the ultraviolet light catalysis synergistic broad-spectrum antibacterial effect.
TABLE 3 ultraviolet and visible light transmittance of PVA composite films of each component
Test specimen
320nm transmittance (%)
500nm transmittance (%)
Example 1
6.5
70.4
Example 2
3.6
70.8
Example 3
1.5
73.5
Example 4
4.6
65.6
Example 5
2.5
69.2
Example 6
1.0
71.5
Example 7
3.4
68.2
Example 8
2.4
72.1
Comparative example 1
30.2
82.4
Comparative example 2
10.4
83.1
Comparative example 3
78.3
84.6
Comparative example 4
80.4
92.0
Comparative example 5
20.6
60.4
Comparative example 6
77.4
88.3
Comparative example 7
15.8
66.6
According to the above test results: compared with comparative examples 1, 2, 3 and 4, the ultraviolet shielding performance of the examples 1 to 8 is obviously improved, but certain transparent performance is sacrificed; also in each of examples and comparative example 5, with TiO2Increased content, improved light transparency, and UV shielding propertyCan be further improved. Compared with the comparative example 1, the ultraviolet shielding capability of the nano lignin in the comparative example 2 is higher, because the nano lignin with small particle size can be uniformly distributed in PVA, and the ultraviolet shielding performance is improved; meanwhile, BHT is colorless and transparent after being dissolved in water, so that the uvioresistant performance of the PVA film is not improved; comparative example 4 aminated modified lignin the ultraviolet transmittance was reduced to 20.6%, but the visible light transmittance after amination was also reduced to 60.4%; by reaction with TiO2The ultraviolet shielding capability of the product obtained by Mannich amination modification after compounding is further improved, in example 6, the ultraviolet shielding performance at 320nm reaches 99.0%, and the light transparency at 500nm is kept at a level of 72.1%, so that the product has higher optical transparency and excellent ultraviolet shielding function, and compared with the example, the ultraviolet shielding performance is improved by more than 35%.
In conclusion, the lignin with high oxidation resistance, antibacterial property and ultraviolet resistance prepared by the invention can be used in the fields of cosmetics, personal care products, biopharmaceuticals, polymer-based composite materials and the like.
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