Encapsulation sun-screening agent with lasting and efficient sun-screening effect and preparation method of encapsulation sun-screening agent

Abstract

The invention discloses an embedded sun-screening agent with a lasting and efficient sun-screening effect and a preparation method thereof.The embedded sun-screening agent is prepared by polymerizing modified cellulose and methacrylic acid under the action of benzoyl peroxide and sodium thiosulfate and coating the surface of a modified inner core with the polymerized modified cellulose and methacrylic acid, and an outer shell of the embedded sun-screening agent contains octocrylene; when the sun-screening agent is smeared on the surface of skin, polydopamine embedded on a shell of the sun-screening agent is influenced by illumination to release octocrylene, the octocrylene can absorb ultraviolet rays, meanwhile, the release amount of the octocrylene is controlled along with the oxidation degree of the polydopamine, the lasting effect is achieved, an inner core is a composite material of a zinc organic framework and nano titanium dioxide, and the sun-screening agent has the advantages that the sun-screening agent can be applied to the skin; the sun-screening agent can reflect and scatter ultraviolet rays, sun-screening components are prevented from being in direct contact with the skin in an organic silicon coating and shell coating mode, the skin is prevented from absorbing inorganic substances, conjugated bonds and pi bonds contained in organic silicon can absorb the ultraviolet rays, and the sun-screening effect of the sun-screening agent is further improved.

Description

Technical Field

[0001] The invention relates to the technical field of sunscreen preparation, and in particular to an embedded sunscreen with long-lasting and high-efficiency sunscreening properties and a preparation method thereof. Background Art

[0002] Ultraviolet radiation causes damage to the skin, such as dry skin, erythema, rapid skin aging, wrinkles, and skin cancer, so ultraviolet protection has become a prominent issue facing human health. More and more people are aware of the damage of ultraviolet rays to the skin, which has led to an increase in the demand for high SPF cosmetics worldwide. In order to protect the skin exposed to ultraviolet rays, designing sunscreen products with high SPF is the most direct and effective method, and a large amount of sunscreen is usually added to the sunscreen. When the amount of sunscreen added is close to the limit dose, it will increase its toxicological risk and cause skin irritation, and the sunscreen effect of the sunscreen will disappear after a period of use. Summary of the invention

[0003] The purpose of the present invention is to provide an embedded sunscreen with long-lasting and efficient sunscreen and a preparation method thereof, which solves the problem that the sunscreen effect of the current sunscreen is not long-lasting and the sunscreen effect is poor.

[0004] The purpose of the present invention can be achieved through the following technical solutions:

[0005] A method for preparing an embedded sunscreen with long-lasting and high-efficiency sunscreen, specifically comprising the following steps:

[0006] Step A1: adding cellulose to octocrylene, ultrasonically treating for 20-30 min at a frequency of 20-30 kHz, filtering to remove the filtrate, dispersing the filter cake in Tris-HCl buffer, stirring at a speed of 150-200 r / min and a temperature of 25-30° C., adding dopamine hydrochloride, and stirring for 20-25 h to obtain pretreated cellulose;

[0007] Step A2: pretreated cellulose, acrylic acid, dicyclohexylcarbodiimide and toluene are mixed evenly, and reacted at a speed of 120-150r / min and a temperature of 60-70°C for 3-5h to obtain modified cellulose; modified cellulose, methyl methacrylate, sodium dodecyl sulfate, modified core, benzoyl peroxide, sodium thiosulfate and deionized water are mixed evenly, nitrogen is introduced for protection, and the reaction is carried out at a temperature of 30-35°C for 6-8h, and the supernatant is removed by centrifugation, and then freeze-dried to obtain an embedded sunscreen agent.

[0008] Furthermore, the dosage ratio of cellulose and octocrylene in step A1 is 1 g:8 mL, the dosage ratio of filter cake, Tris-HCl buffer and dopamine hydrochloride is 5 g:100 mL:1 g, the concentration of Tris-HCl buffer is 10 mmol / L, and the pH is 8.5.

[0009] Furthermore, the molar ratio of amino, acrylic acid and dicyclohexylcarbodiimide on the pretreated cellulose in step A2 is 1:1.2:1, and the amount ratio of modified cellulose, methyl methacrylate, sodium dodecyl sulfate, modified core, benzoyl peroxide, sodium thiosulfate and deionized water is 1g:4g:30mg:1g:3mg:3mg:20mL.

[0010] Further, the modified kernel is prepared by the following steps:

[0011] Step B1: p-Hydroxybenzaldehyde, 3-chloropropyltrimethoxysilane, anhydrous aluminum chloride and DMF are mixed evenly, nitrogen is introduced for protection, and the reaction is carried out for 3-5 hours at a speed of 120-150 r / min and a temperature of 80-85° C. to obtain intermediate 1; diethyl malonate, potassium hydroxide and ethanol are mixed evenly, nitrogen is introduced for protection, and glacial acetic acid is added under stirring at a speed of 150-200 r / min and a temperature of 20-25° C. to react for 30-40 minutes; intermediate 1, proline and tripotassium phosphate are added, the temperature is raised to 70-75° C., and the reaction is carried out for 10-15 hours to obtain intermediate 2;

[0012] Step B2: The intermediate 2, isooctyl alcohol, p-toluenesulfonic acid and toluene are uniformly mixed, nitrogen is introduced for protection, and the reaction is carried out for 5-7 hours at a speed of 120-150 r / min and a temperature of 110-115° C. to obtain a modifier, 2-aminobenzimidazole is dissolved in DMF, and sodium hydroxide is added under stirring at a speed of 120-150 r / min and a temperature of 25-30° C., and the mixture is stirred for 10-15 minutes, zinc nitrate hexahydrate is added, and the mixture is stirred for 10-15 minutes, and the temperature is raised to 150-155° C. and the reaction is carried out for 20-25 hours to obtain a zinc organic framework;

[0013] Step B3: Mix the zinc organic framework, tetrabutyl titanate and DMF, stir and add hydrofluoric acid and deionized water at a speed of 300-500 r / min and a temperature of 40-50°C, heat to 180-185°C, perform hydrothermal reaction for 20-25h, adjust the pH value to 7.5-8, and obtain a precursor. Disperse the precursor in toluene, introduce nitrogen protection, stir and add isocyanate propyl triethoxysilane at a speed of 60-80 r / min and a temperature of 20-25°C, and react for 1-1.5h to obtain a modified precursor;

[0014] Step B4: Mix the modified precursor, modifier, dimethyldiethoxysilane, methyltriethoxysilane and DMF evenly, introduce nitrogen protection, stir and add deionized water and hydrochloric acid solution at a speed of 120-150r / min and a temperature of 65-70°C, react for 3-5h, heat to 120-130°C, react for 2-3h, and obtain a modified core.

[0015] Furthermore, the molar ratio of p-hydroxybenzaldehyde, 3-chloropropyltrimethoxysilane and anhydrous aluminum chloride described in step B1 is 1:1.2:1, and the usage ratio of diethyl malonate, potassium hydroxide, ethanol, glacial acetic acid, intermediate 1, proline and tripotassium phosphate is 16mmol:16mmol:60mL:16mmol:10mmol:3mmol:0.5mmol.

[0016] Furthermore, the molar ratio of the intermediate 2 and isooctyl alcohol in step B2 is 1:4, the amount of p-toluenesulfonic acid used is 10% of the mass of the intermediate 2, and the molar ratio of 2-aminobenzimidazole, sodium hydroxide and zinc nitrate hexahydrate is 2:1:1.

[0017] Furthermore, the dosage ratio of the zinc organic framework, tetrabutyl titanate, DMF, hydrofluoric acid and deionized water described in step B3 is 5g:15mL:80mL:2mL:3mL, and the molar ratio of amino group and isocyanatepropyltriethoxysilane on the precursor is 1:1.

[0018] Furthermore, the amount ratio of the modified precursor, modifier, dimethyldiethoxysilane, methyltriethoxysilane, DMF, deionized water and hydrochloric acid solution described in step B4 is 5g:1g:8mL:10mL:60mL:10mL:10mL, and the mass fraction of the hydrochloric acid solution is 10%.

[0019] The beneficial effects of the present invention are as follows: the embedded sunscreen with long-lasting and high-efficiency sunscreen prepared by the present invention uses cellulose as a raw material, cellulose is soaked in octocrylene, the cellulose contains a large number of voids and channels that can absorb octocrylene, polydopamine is coated on the surface to obtain pretreated cellulose, the pretreated cellulose is reacted with acrylic acid, the amino groups on the pretreated cellulose and the carboxyl groups on the acrylic acid are dehydrated to obtain modified cellulose, the modified cellulose, methacrylic acid, sodium dodecyl sulfate, a modified inner core, benzoyl peroxide and sodium thiosulfate are mixed, the modified cellulose and methacrylic acid are polymerized under the action of benzoyl peroxide and sodium thiosulfate, and the modified cellulose and methacrylic acid are coated on the surface of the modified inner core to obtain the embedded sunscreen.

[0020] The modified core is prepared by using p-hydroxybenzaldehyde and 3-chloropropyltrimethoxysilane as raw materials. Under the action of anhydrous aluminum chloride, the hydroxyl group on p-hydroxybenzaldehyde reacts with the chlorine atom site on 3-chloropropyltrimethoxysilane to obtain intermediate 1. Diethyl malonate is reacted with intermediate 1 to condense the aldehyde group on intermediate 1 with the dimethyl group on diethyl malonate to obtain intermediate 2. Intermediate 2 is reacted with isooctyl alcohol to exchange the ester group on intermediate 2 with the alcohol hydroxyl group on isooctyl alcohol to obtain a modifier. 2 is reacted with diethyl malonate to obtain intermediate 1. -aminobenzimidazole is reacted with zinc nitrate hexahydrate to obtain a zinc organic framework, nano-titanium dioxide is then loaded in the pores of the zinc organic framework to obtain a precursor, the precursor is reacted with isocyanate propyl triethoxysilane, so that the amino group on the precursor reacts with the isocyanate on the isocyanate propyl triethoxysilane to obtain a modified precursor, the modified precursor, the modifier, dimethyl diethoxy silane and methyl triethoxy silane are hydrolyzed and condensed to form an organic silicon coating on the surface of the modified precursor to obtain a modified core.

[0021] The shell of the embedded sunscreen contains octocrylene. When the sunscreen is applied to the skin surface, the polydopamine on the shell of the embedded sunscreen releases octocrylene under the influence of light. Octocrylene can absorb ultraviolet rays and reduce the generation of free radicals, thereby protecting skin cells from oxidative stress. At the same time, as the degree of oxidation of polydopamine increases, the release amount of octocrylene is controlled to achieve a lasting effect. Octocrylene is non-toxic and will not harm the skin. The core is a composite material of zinc organic framework and nano-titanium dioxide, which can reflect and scatter ultraviolet rays and prevent them from penetrating the surface of the skin, thereby reducing damage to the skin. The organic silicon coating and the shell coating prevent the sunscreen ingredients from directly contacting the skin and avoiding the skin from absorbing inorganic substances. The organic silicon contains conjugated bonds and π bonds that can absorb ultraviolet rays, further improving the sunscreen effect of the sunscreen. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Example 1

[0024] A method for preparing an embedded sunscreen with long-lasting and high-efficiency sunscreen, specifically comprising the following steps:

[0025] Step A1: adding cellulose to octocrylene, ultrasonically treating for 20 min at a frequency of 20 kHz, filtering to remove the filtrate, dispersing the filter cake in Tris-HCl buffer, stirring at a speed of 150 r / min and a temperature of 25° C., adding dopamine hydrochloride, and stirring for 20 h to obtain pretreated cellulose;

[0026] Step A2: Pretreated cellulose, acrylic acid, dicyclohexylcarbodiimide and toluene are mixed evenly, and reacted at a speed of 120 r / min and a temperature of 60°C for 3 hours to obtain modified cellulose; modified cellulose, methyl methacrylate, sodium dodecyl sulfate, modified core, benzoyl peroxide, sodium thiosulfate and deionized water are mixed evenly, nitrogen is introduced for protection, and the reaction is carried out at a temperature of 30°C for 6 hours, and then the supernatant is removed by centrifugation, and then freeze-dried to obtain an embedded sunscreen agent.

[0027] The dosage ratio of cellulose and octocrylene in step A1 is 1 g:8 mL, the dosage ratio of filter cake, Tris-HCl buffer and dopamine hydrochloride is 5 g:100 mL:1 g, the concentration of Tris-HCl buffer is 10 mmol / L, and the pH is 8.5.

[0028] The molar ratio of amino, acrylic acid and dicyclohexylcarbodiimide on the pretreated cellulose in step A2 is 1:1.2:1, and the amount ratio of modified cellulose, methyl methacrylate, sodium dodecyl sulfate, modified core, benzoyl peroxide, sodium thiosulfate and deionized water is 1g:4g:30mg:1g:3mg:3mg:20mL.

[0029] The modified core is prepared by the following steps:

[0030] Step B1: p-Hydroxybenzaldehyde, 3-chloropropyltrimethoxysilane, anhydrous aluminum chloride and DMF were mixed evenly, nitrogen was introduced for protection, and the reaction was carried out for 3 hours at a speed of 120 r / min and a temperature of 80°C to obtain intermediate 1. Diethyl malonate, potassium hydroxide and ethanol were mixed evenly, nitrogen was introduced for protection, and glacial acetic acid was added under stirring at a speed of 150 r / min and a temperature of 20°C, and the reaction was carried out for 30 minutes. Intermediate 1, proline and tripotassium phosphate were added, the temperature was raised to 70°C, and the reaction was carried out for 10 hours to obtain intermediate 2;

[0031] Step B2: The intermediate 2, isooctyl alcohol, p-toluenesulfonic acid and toluene are uniformly mixed, nitrogen is introduced for protection, and the reaction is carried out for 5 hours at a speed of 120 r / min and a temperature of 110° C. to obtain a modifier, 2-aminobenzimidazole is dissolved in DMF, and sodium hydroxide is added under stirring at a speed of 120 r / min and a temperature of 25-30° C., and the mixture is stirred for 10 minutes, zinc nitrate hexahydrate is added, and the mixture is stirred for 10 minutes, and the temperature is raised to 150° C. and the reaction is carried out for 20 hours to obtain a zinc organic framework;

[0032] Step B3: Mix the zinc organic framework, tetrabutyl titanate and DMF, stir and add hydrofluoric acid and deionized water at a speed of 300 r / min and a temperature of 40°C, heat to 180°C, perform hydrothermal reaction for 20 hours, adjust the pH value to 7.5, and obtain a precursor. Disperse the precursor in toluene, introduce nitrogen protection, stir and add isocyanate propyl triethoxysilane at a speed of 60 r / min and a temperature of 20°C, and react for 1 hour to obtain a modified precursor;

[0033] Step B4: Mix the modified precursor, modifier, dimethyldiethoxysilane, methyltriethoxysilane and DMF evenly, introduce nitrogen protection, stir and add deionized water and hydrochloric acid solution at a speed of 120r / min and a temperature of 65°C, react for 3h, heat to 120°C, react for 2h, and obtain a modified core.

[0034] The molar ratio of p-hydroxybenzaldehyde, 3-chloropropyltrimethoxysilane and anhydrous aluminum chloride described in step B1 is 1:1.2:1, and the usage ratio of diethyl malonate, potassium hydroxide, ethanol, glacial acetic acid, intermediate 1, proline and tripotassium phosphate is 16mmol:16mmol:60mL:16mmol:10mmol:3mmol:0.5mmol.

[0035] The molar ratio of the intermediate 2 and isooctyl alcohol described in step B2 is 1:4, the amount of p-toluenesulfonic acid used is 10% of the mass of the intermediate 2, and the molar ratio of 2-aminobenzimidazole, sodium hydroxide and zinc nitrate hexahydrate is 2:1:1.

[0036] The amount ratio of the zinc organic framework, tetrabutyl titanate, DMF, hydrofluoric acid and deionized water described in step B3 is 5g:15mL:80mL:2mL:3mL, and the molar ratio of amino group and isocyanate propyltriethoxysilane on the precursor is 1:1.

[0037] The amount ratio of the modified precursor, modifier, dimethyldiethoxysilane, methyltriethoxysilane, DMF, deionized water and hydrochloric acid solution described in step B4 is 5g:1g:8mL:10mL:60mL:10mL:10mL, and the mass fraction of the hydrochloric acid solution is 10%.

[0038] Example 2

[0039] A method for preparing an embedded sunscreen with long-lasting and high-efficiency sunscreen, specifically comprising the following steps:

[0040] Step A1: adding cellulose to octocrylene, ultrasonically treating for 25 min at a frequency of 25 kHz, filtering to remove the filtrate, dispersing the filter cake in Tris-HCl buffer, stirring at a speed of 150 r / min and a temperature of 30° C., adding dopamine hydrochloride, and stirring for 20 h to obtain pretreated cellulose;

[0041] Step A2: Pretreated cellulose, acrylic acid, dicyclohexylcarbodiimide and toluene are mixed evenly, and reacted at a speed of 120 r / min and a temperature of 65°C for 4 hours to obtain modified cellulose; modified cellulose, methyl methacrylate, sodium dodecyl sulfate, modified core, benzoyl peroxide, sodium thiosulfate and deionized water are mixed evenly, nitrogen is introduced for protection, and the reaction is carried out at a temperature of 35°C for 7 hours, and then the supernatant is removed by centrifugation, and then freeze-dried to obtain an embedded sunscreen agent.

[0042] The dosage ratio of cellulose and octocrylene in step A1 is 1 g:8 mL, the dosage ratio of filter cake, Tris-HCl buffer and dopamine hydrochloride is 5 g:100 mL:1 g, the concentration of Tris-HCl buffer is 10 mmol / L, and the pH is 8.5.

[0043] The molar ratio of amino, acrylic acid and dicyclohexylcarbodiimide on the pretreated cellulose in step A2 is 1:1.2:1, and the amount ratio of modified cellulose, methyl methacrylate, sodium dodecyl sulfate, modified core, benzoyl peroxide, sodium thiosulfate and deionized water is 1g:4g:30mg:1g:3mg:3mg:20mL.

[0044] The modified core is prepared by the following steps:

[0045] Step B1: p-Hydroxybenzaldehyde, 3-chloropropyltrimethoxysilane, anhydrous aluminum chloride and DMF were mixed evenly, nitrogen was introduced for protection, and the reaction was carried out for 4 hours at a speed of 150 r / min and a temperature of 83°C to obtain intermediate 1. Diethyl malonate, potassium hydroxide and ethanol were mixed evenly, nitrogen was introduced for protection, and glacial acetic acid was added under stirring at a speed of 150 r / min and a temperature of 25°C, and the reaction was carried out for 35 minutes. Intermediate 1, proline and tripotassium phosphate were added, the temperature was raised to 75°C, and the reaction was carried out for 10 hours to obtain intermediate 2;

[0046] Step B2: The intermediate 2, isooctyl alcohol, p-toluenesulfonic acid and toluene are uniformly mixed, nitrogen is introduced for protection, and the reaction is carried out for 6 hours at a speed of 150 r / min and a temperature of 110° C. to obtain a modifier, 2-aminobenzimidazole is dissolved in DMF, and sodium hydroxide is added under stirring at a speed of 120 r / min and a temperature of 30° C., and the mixture is stirred for 10 minutes, zinc nitrate hexahydrate is added, and the mixture is stirred for 15 minutes, and the temperature is raised to 150° C. and the reaction is carried out for 25 hours to obtain a zinc organic framework;

[0047] Step B3: Mix the zinc organic framework, tetrabutyl titanate and DMF, stir and add hydrofluoric acid and deionized water at a speed of 500 r / min and a temperature of 45°C, heat to 185°C, perform hydrothermal reaction for 25 hours, adjust the pH value to 7.5, and obtain a precursor. Disperse the precursor in toluene, introduce nitrogen protection, stir and add isocyanate propyl triethoxysilane at a speed of 60 r / min and a temperature of 25°C, and react for 1.3 hours to obtain a modified precursor;

[0048] Step B4: Mix the modified precursor, modifier, dimethyldiethoxysilane, methyltriethoxysilane and DMF evenly, introduce nitrogen protection, stir and add deionized water and hydrochloric acid solution at a speed of 150r / min and a temperature of 65°C, react for 4 hours, heat to 125°C, react for 3 hours, and obtain a modified core.

[0049] The molar ratio of p-hydroxybenzaldehyde, 3-chloropropyltrimethoxysilane and anhydrous aluminum chloride described in step B1 is 1:1.2:1, and the usage ratio of diethyl malonate, potassium hydroxide, ethanol, glacial acetic acid, intermediate 1, proline and tripotassium phosphate is 16mmol:16mmol:60mL:16mmol:10mmol:3mmol:0.5mmol.

[0050] The molar ratio of the intermediate 2 and isooctyl alcohol described in step B2 is 1:4, the amount of p-toluenesulfonic acid used is 10% of the mass of the intermediate 2, and the molar ratio of 2-aminobenzimidazole, sodium hydroxide and zinc nitrate hexahydrate is 2:1:1.

[0051] The amount ratio of the zinc organic framework, tetrabutyl titanate, DMF, hydrofluoric acid and deionized water described in step B3 is 5g:15mL:80mL:2mL:3mL, and the molar ratio of amino group and isocyanate propyltriethoxysilane on the precursor is 1:1.

[0052] The amount ratio of the modified precursor, modifier, dimethyldiethoxysilane, methyltriethoxysilane, DMF, deionized water and hydrochloric acid solution described in step B4 is 5g:1g:8mL:10mL:60mL:10mL:10mL, and the mass fraction of the hydrochloric acid solution is 10%.

[0053] Example 3

[0054] A method for preparing an embedded sunscreen with long-lasting and high-efficiency sunscreen, specifically comprising the following steps:

[0055] Step A1: adding cellulose to octocrylene, ultrasonically treating for 30 min at a frequency of 30 kHz, filtering to remove the filtrate, dispersing the filter cake in Tris-HCl buffer, stirring at a speed of 200 r / min and a temperature of 30° C., adding dopamine hydrochloride, and stirring for 25 h to obtain pretreated cellulose;

[0056] Step A2: Pretreated cellulose, acrylic acid, dicyclohexylcarbodiimide and toluene are mixed evenly, and reacted at a speed of 150 r / min and a temperature of 70°C for 5 hours to obtain modified cellulose; modified cellulose, methyl methacrylate, sodium dodecyl sulfate, modified core, benzoyl peroxide, sodium thiosulfate and deionized water are mixed evenly, nitrogen is introduced for protection, and the reaction is carried out at a temperature of 35°C for 8 hours, and then the supernatant is removed by centrifugation, and then freeze-dried to obtain an embedded sunscreen agent.

[0057] The dosage ratio of cellulose and octocrylene in step A1 is 1 g:8 mL, the dosage ratio of filter cake, Tris-HCl buffer and dopamine hydrochloride is 5 g:100 mL:1 g, the concentration of Tris-HCl buffer is 10 mmol / L, and the pH is 8.5.

[0058] The molar ratio of amino, acrylic acid and dicyclohexylcarbodiimide on the pretreated cellulose in step A2 is 1:1.2:1, and the amount ratio of modified cellulose, methyl methacrylate, sodium dodecyl sulfate, modified core, benzoyl peroxide, sodium thiosulfate and deionized water is 1g:4g:30mg:1g:3mg:3mg:20mL.

[0059] The modified core is prepared by the following steps:

[0060] Step B1: p-Hydroxybenzaldehyde, 3-chloropropyltrimethoxysilane, anhydrous aluminum chloride and DMF were mixed evenly, nitrogen was introduced for protection, and the reaction was carried out at a speed of 150 r / min and a temperature of 85°C for 5 hours to obtain intermediate 1. Diethyl malonate, potassium hydroxide and ethanol were mixed evenly, nitrogen was introduced for protection, and glacial acetic acid was added under stirring at a speed of 200 r / min and a temperature of 25°C, and the reaction was carried out for 40 minutes. Intermediate 1, proline and tripotassium phosphate were added, the temperature was raised to 75°C, and the reaction was carried out for 15 hours to obtain intermediate 2;

[0061] Step B2: The intermediate 2, isooctyl alcohol, p-toluenesulfonic acid and toluene are uniformly mixed, nitrogen is introduced for protection, and the reaction is carried out for 7 hours at a speed of 150 r / min and a temperature of 115° C. to obtain a modifier, 2-aminobenzimidazole is dissolved in DMF, and sodium hydroxide is added under stirring at a speed of 150 r / min and a temperature of 30° C., and the mixture is stirred for 15 minutes, zinc nitrate hexahydrate is added, and the mixture is stirred for 15 minutes, and the temperature is raised to 155° C. and the reaction is carried out for 25 hours to obtain a zinc organic framework;

[0062] Step B3: Mix the zinc organic framework, tetrabutyl titanate and DMF, stir and add hydrofluoric acid and deionized water at a speed of 500 r / min and a temperature of 50°C, heat to 185°C, perform hydrothermal reaction for 25 hours, adjust the pH value to 8, and obtain a precursor. Disperse the precursor in toluene, introduce nitrogen protection, stir and add isocyanate propyl triethoxysilane at a speed of 80 r / min and a temperature of 25°C, and react for 1.5 hours to obtain a modified precursor.

[0063] Step B4: Mix the modified precursor, modifier, dimethyldiethoxysilane, methyltriethoxysilane and DMF evenly, introduce nitrogen protection, stir and add deionized water and hydrochloric acid solution at a speed of 150r / min and a temperature of 70°C, react for 5h, heat to 130°C, react for 3h, and obtain a modified core.

[0064] The molar ratio of p-hydroxybenzaldehyde, 3-chloropropyltrimethoxysilane and anhydrous aluminum chloride described in step B1 is 1:1.2:1, and the usage ratio of diethyl malonate, potassium hydroxide, ethanol, glacial acetic acid, intermediate 1, proline and tripotassium phosphate is 16mmol:16mmol:60mL:16mmol:10mmol:3mmol:0.5mmol.

[0065] The molar ratio of the intermediate 2 and isooctyl alcohol described in step B2 is 1:4, the amount of p-toluenesulfonic acid used is 10% of the mass of the intermediate 2, and the molar ratio of 2-aminobenzimidazole, sodium hydroxide and zinc nitrate hexahydrate is 2:1:1.

[0066] The amount ratio of the zinc organic framework, tetrabutyl titanate, DMF, hydrofluoric acid and deionized water described in step B3 is 5g:15mL:80mL:2mL:3mL, and the molar ratio of amino group and isocyanate propyltriethoxysilane on the precursor is 1:1.

[0067] The amount ratio of the modified precursor, modifier, dimethyldiethoxysilane, methyltriethoxysilane, DMF, deionized water and hydrochloric acid solution described in step B4 is 5g:1g:8mL:10mL:60mL:10mL:10mL, and the mass fraction of the hydrochloric acid solution is 10%.

[0068] Comparative Example 1

[0069] Compared with Example 1, this comparative example did not add modified cellulose, and the remaining steps were the same.

[0070] Comparative Example 2

[0071] Compared with Example 1, no modifier was added in this comparative example, and the remaining steps were the same.

[0072] Comparative Example 3

[0073] Compared with Example 1, this comparative example uses a precursor instead of the modified core, and the remaining steps are the same.

[0074] Comparative Example 4

[0075] Compared with Example 1, this comparative example uses nano titanium dioxide to replace the modified core, and the other steps are the same.

[0076] The embedded sunscreens prepared in Examples 1-3 and Comparative Examples 1-4 were dispersed in double distilled water, and their absorption of ultraviolet rays within the wavelength range of 260nm, 300nm, 350nm and 400nm was detected by UV-visible absorption spectrometer to detect light protection. The test results are shown below.

[0077]

[0078] This shows that the present invention has a good sun protection effect.

[0079] The above contents are merely examples and explanations of the concept of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A method for preparing an embedded sunscreen with long-lasting and efficient sunscreen, characterized in that: The specific steps include: Step A1: adding cellulose to octocrylene, ultrasonically treating, filtering to remove the filtrate, dispersing the filter cake in Tris-HCl buffer, stirring and adding dopamine hydrochloride, stirring for 20-25 hours, to obtain pretreated cellulose; Step A2: pretreated cellulose, acrylic acid, dicyclohexylcarbodiimide and toluene are mixed and reacted to obtain modified cellulose, and the modified cellulose, methyl methacrylate, sodium dodecyl sulfate, modified core, benzoyl peroxide, sodium thiosulfate and deionized water are mixed evenly, nitrogen is introduced for protection, and after the reaction, the supernatant is removed by centrifugation, and then freeze-dried at low temperature to obtain an embedded sunscreen agent.

2. The method for preparing a sunscreen with long-lasting and high-efficiency sunscreen according to claim 1, characterized in that: The usage ratio of cellulose and octocrylene in step A1 is 1 g:8 mL, and the usage ratio of filter cake, Tris-HCl buffer and dopamine hydrochloride is 5 g:100 mL:1 g.

3. The method for preparing a long-lasting and highly effective sunscreen embedded sunscreen according to claim 1, characterized in that: The molar ratio of amino, acrylic acid and dicyclohexylcarbodiimide on the pretreated cellulose in step A2 is 1:1.2:1, and the amount ratio of modified cellulose, methyl methacrylate, sodium dodecyl sulfate, modified core, benzoyl peroxide, sodium thiosulfate and deionized water is 1g:4g:30mg:1g:3mg:3mg:20mL.

4. The method for preparing a sunscreen with long-lasting and high-efficiency sunscreen according to claim 1, characterized in that: The modified core is prepared by the following steps: Step B1: p-Hydroxybenzaldehyde, 3-chloropropyltrimethoxysilane, anhydrous aluminum chloride and DMF are mixed evenly, nitrogen is introduced for protection, and the mixture is reacted to obtain intermediate 1; diethyl malonate, potassium hydroxide and ethanol are mixed evenly, nitrogen is introduced for protection, glacial acetic acid is added with stirring, and the mixture is reacted; intermediate 1, proline and tripotassium phosphate are added, and the mixture is heated for reaction to obtain intermediate 2; Step B2: The intermediate 2, isooctyl alcohol, p-toluenesulfonic acid and toluene are uniformly mixed, nitrogen is introduced for protection, and a reaction is carried out to obtain a modifier, 2-aminobenzimidazole is dissolved in DMF, and sodium hydroxide is added after stirring, and zinc nitrate hexahydrate is added after stirring, and the temperature is raised to react to obtain a zinc organic framework; Step B3: Mix and stir the zinc organic framework, tetrabutyl titanate and DMF, add hydrofluoric acid and deionized water, heat up for hydrothermal reaction, adjust the pH value to be alkaline, prepare a precursor, disperse the precursor in toluene, introduce nitrogen for protection, stir and add isocyanate propyl triethoxysilane, react, and prepare a modified precursor; Step B4: uniformly mix the modified precursor, the modifier, dimethyldiethoxysilane, methyltriethoxysilane and DMF, introduce nitrogen protection, stir and add deionized water and hydrochloric acid solution to react to obtain a modified core.

5. The method for preparing a sunscreen with long-lasting and high-efficiency sunscreen according to claim 4, characterized in that: The molar ratio of p-hydroxybenzaldehyde, 3-chloropropyltrimethoxysilane and anhydrous aluminum chloride described in step B1 is 1:1.2:1, and the dosage ratio of diethyl malonate, potassium hydroxide, ethanol, glacial acetic acid, intermediate 1, proline and tripotassium phosphate is 16mmo l:16mmo l:60mL:16mmo l:10mmo l:3mmo l:0.5mmo l.

6. The method for preparing a long-lasting and highly effective sunscreen embedded sunscreen according to claim 4, characterized in that: The molar ratio of intermediate 2 and isooctyl alcohol described in step B2 is 1:4, and the molar ratio of 2-aminobenzimidazole, sodium hydroxide and zinc nitrate hexahydrate is 2:1:

1.

7. The method for preparing a long-lasting and highly effective sunscreen embedded sunscreen according to claim 4, characterized in that: The amount ratio of the zinc organic framework, tetrabutyl titanate, DMF, hydrofluoric acid and deionized water described in step B3 is 5g:15mL:80mL:2mL:3mL, and the molar ratio of amino group and isocyanate propyltriethoxysilane on the precursor is 1:

1.

8. The method for preparing a sunscreen with long-lasting and high-efficiency sunscreen according to claim 1, characterized in that: The amount ratio of the modified precursor, modifier, dimethyldiethoxysilane, methyltriethoxysilane, DMF, deionized water and hydrochloric acid solution described in step B4 is 5g:1g:8mL:10mL:60mL:10mL:10mL.

9. An embedded sunscreen with long-lasting and efficient sunscreen, characterized in that: Prepared according to any one of claims 1 to 8.

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