Anti-aging foamed sponge material and preparation method thereof

Abstract

The invention relates to the technical field of sponge materials, in particular to an anti-aging foamed sponge material and a preparation method thereof.The preparation method comprises the steps that when polyvinyl alcohol serves as a raw material to prepare foamed sponge, gelatin and composite titanium dioxide are introduced, alkali lignin serves as a biological template inducer for the composite titanium dioxide, titanium dioxide composite nanoparticles are synthesized through a hydrothermal method, and lysine is grafted; the flame retardant is prepared by in-situ demethylation modification and grafting of a boron-containing Schiff base flame retardant prepared by using monoethanolamine borate and 2, 4-dihydroxybenzaldehyde as raw materials by using a catechol structure. Composite titanium dioxide, dialdehyde chitosan, modified gelatin, deionized water and acetic acid are mixed to prepare a protective impregnation liquid, and a complex cross-linked network is constructed by controlling the mass ratio of the sum of the mass of the composite titanium dioxide and the mass of the dialdehyde chitosan to the mass of the modified gelatin, so that the antibacterial, flame-retardant and anti-aging foamed sponge material is obtained.

Description

Technical Field

[0001] The invention relates to the technical field of sponge materials, in particular to an anti-aging foaming sponge material and a preparation method thereof. Background Art

[0002] Foam sponges, which can be used to create high-performance materials such as gaskets, seals, insulation, and shock absorbers, are widely used in defense, aviation, electronics, and construction. Foam sponges are typically formed from a foaming liquid. As environmental awareness grows, consumers are increasingly interested in biodegradable foam sponges, such as polyvinyl alcohol sponges, which are composed of a mesh structure formed by cross-linking numerous polymer chains.

[0003] However, traditional polyvinyl alcohol foam sponges have limited thermal stability and aging resistance, poor antibacterial and flame retardancy, and cannot meet the growing needs of consumers. Therefore, the development of a foam sponge material that has good mechanical strength, antibacterial, flame retardancy, and aging resistance has practical significance and economic value. Summary of the Invention

[0004] The purpose of the present invention is to provide an anti-aging foam sponge material and a preparation method thereof, so as to solve the problems in the prior art.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: A method for preparing an anti-aging foam sponge material comprises the following steps: S1: Prepare a foam sponge using composite titanium dioxide, gelatin, and polyvinyl alcohol as raw materials; S2: mixing composite titanium dioxide, dialdehyde chitosan, modified gelatin, deionized water, and acetic acid to obtain a protective impregnation solution; S3: cleaning and drying the foamed sponge, then immersing the foamed sponge in a protective impregnation liquid for immersion treatment, taking it out and drying it to obtain an anti-aging foamed sponge material.

[0006] Furthermore, the working conditions of the immersion treatment are: temperature of 25-30° C., and time of 2-4 minutes.

[0007] Furthermore, the preparation of the foamed sponge comprises the following steps: Mix polyvinyl alcohol and deionized water, heat to 85-95°C and keep warm for 20-30 minutes, add a mixture of gelatin and deionized water, stir for 55-65 minutes, cool to 63-67°C, add composite titanium dioxide and sulfuric acid in sequence, stir for 5-7 minutes, add emulsifier OP-10, stir and foam for 7-8 minutes, add formaldehyde solution, transfer to a mold, and keep warm at 60°C for 5-6 hours to obtain a foamed sponge.

[0008] Furthermore, the usage ratio of composite titanium dioxide, gelatin, polyvinyl alcohol and formaldehyde is 2g:5g:20g:32mL.

[0009] Furthermore, using deionized water as solvent, the composition of the protective impregnation solution is: (6-8) g / L composite titanium dioxide, 18 g / L dialdehyde chitosan, (36-39) g / L modified gelatin, and 2 g / L acetic acid.

[0010] Furthermore, the mass ratio of the sum of the mass of the composite titanium dioxide and the dialdehyde chitosan to the mass of the modified gelatin is 2:3.

[0011] Furthermore, the preparation of modified gelatin comprises the following steps: Mix gelatin and deionized water, dissolve in a 48-52°C water bath, add ε-polylysine, add microbial transglutaminase, keep warm for 11-12 hours, heat to 95°C water bath for 5-6 minutes, dialyze for 3 days, and freeze-dry to obtain modified gelatin.

[0012] Furthermore, the preparation of composite titanium dioxide comprises the following steps: 1) Anhydrous ethanol and butyl titanate were mixed, sulfuric acid solution was added, and the mixture was stirred for 20-30 minutes. A mixed solution of alkali lignin and deionized water was added, and the mixture was transferred to a reactor, kept at 118-120°C for 110-130 minutes, allowed to stand for 22-24 hours, and dried to obtain titanium dioxide composite nanoparticles; 2) Under a nitrogen atmosphere, titanium dioxide composite nanoparticles, lysine, and sodium hydroxide aqueous solution were mixed, the pH was adjusted to 11, the temperature was raised to 58-60°C, glyoxal solution and deionized water were added, the temperature was kept for 3-4 hours, the mixture was cooled to 18-25°C, the pH was adjusted to 7-7.5, the mixture was centrifuged, dialyzed for 3 days, and dried to obtain grafted titanium dioxide composite nanoparticles; 3) Under a nitrogen atmosphere, the grafted titanium dioxide composite nanoparticles and N,N-dimethylformamide are mixed, the temperature is raised to 148-150°C, iodocyclohexane is added, the temperature is kept for 11-12 hours, and the mixture is extracted 3-5 times with n-hexane as an extractant. A saturated sodium metabisulfite solution is added, and the mixture is filtered, washed, freeze-dried, and ground to obtain modified titanium dioxide composite nanoparticles; 4) The modified titanium dioxide composite nanoparticles, the boron-containing Schiff base flame retardant, and the Tris-HCl buffer were mixed, ultrasonically stirred for 1-2 hours, and heated to 30-40° C. and kept warm for 2-3 hours to obtain composite titanium dioxide.

[0013] Furthermore, the preparation of the boron-containing Schiff base flame retardant comprises the following steps: Mix monoethanolamine borate and anhydrous ethanol, add 2,4-dihydroxybenzaldehyde, stir at 18-25° C. for 11-12 hours, filter under reduced pressure, wash, and dry to obtain a boron-containing Schiff base flame retardant.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides an anti-aging foam sponge material and a preparation method thereof. By optimizing the components and the process, a foam sponge material with good mechanical strength, antibacterial properties, flame retardancy and anti-aging properties is prepared.

[0015] When preparing foam sponge with polyvinyl alcohol as raw material, the biodegradable and green biomass material gelatin is introduced to improve the mechanical strength of the matrix without affecting the pore structure of the matrix. In order to further improve the light and heat aging resistance of the sponge foam material, titanium dioxide and lignin are introduced into the foam sponge as anti-aging agents. In order to improve the uniformity of the dispersion of titanium dioxide and lignin in the foam sponge and improve the uniformity of the material, alkali lignin is used as a biological template inducer to synthesize titanium dioxide composite nanoparticles with good UV shielding properties through a hydrothermal method, and then Lysine with antibacterial properties is grafted and then in situ demethylated to obtain modified titanium dioxide composite nanoparticles with multiple functional groups such as carboxyl, aldehyde, and catechol structures. The catechol structure is then used to graft a boron-containing Schiff base flame retardant prepared with monoethanolamine borate and 2,4-dihydroxybenzaldehyde as raw materials to obtain a composite titanium dioxide containing both borate bonds and Schiff base dynamic bonds, aldehyde groups, carboxyl groups and other active sites, thereby improving the bonding strength between the composite titanium dioxide and the foam sponge and giving the sponge excellent flame retardancy and shape retention.

[0016] In order to further improve the antibacterial properties of the foaming sponge and solve the problem of possible residual free aldehydes during sponge foaming, the present invention prepares a protective impregnation liquid by mixing composite titanium dioxide, dialdehyde chitosan, modified gelatin, deionized water, and acetic acid. The modified gelatin uses gelatin as a raw material and glutamine transaminase as a catalyst. ε-polylysine with biocompatibility, biodegradability, and antibacterial properties is grafted onto the gelatin peptide chain to increase the free amino groups available for reaction in the gelatin molecules. By controlling the mass ratio of the sum of the mass of the composite titanium dioxide and dialdehyde chitosan to the mass of the modified gelatin, a complex cross-linked network is constructed, thereby obtaining an antibacterial, flame-retardant, and anti-aging foaming sponge material. DETAILED DESCRIPTION

[0017] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0018] It should be noted that if the embodiments of the present invention involve directional indications such as up, down, left, right, front, and back, such directional indications are only used to explain a specific posture, such as the relative position relationship between components, the movement status, etc. If the specific posture changes, the directional indication will also change accordingly. In addition, the technical solutions between the various embodiments may be combined with each other, but they must be based on the premise that they can be implemented by ordinary technicians in this field. If the combination of technical solutions is mutually inconsistent or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0019] The technical solutions of the present invention are further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely used to explain the present invention and are not intended to limit the present invention.

[0020] Example 1: A method for preparing an anti-aging foam sponge material, comprising the following steps: S1: Prepare a foam sponge using composite titanium dioxide, gelatin, and polyvinyl alcohol as raw materials; The preparation of the foaming sponge comprises the following steps: 20 g of polyvinyl alcohol and 200 mL of deionized water were mixed, heated to 85°C and kept warm for 30 min, a mixture of 5 g of gelatin and 10 mL of deionized water was added, stirred at 700 rpm for 55 min, cooled to 63°C, 2 g of composite titanium dioxide and 20 g of 8 mol / L sulfuric acid were added in sequence, stirred for 5 min, 14 mL of emulsifier OP-10 was added, stirred and foamed for 7 min, 32 mL of 37% formaldehyde solution was added, the mixture was transferred to a mold, and kept warm at 60°C for 5 h to obtain a foamed sponge; The preparation of the composite titanium dioxide comprises the following steps: 1) Mix 60 mL of anhydrous ethanol and 20 mL of butyl titanate, add 4 mL of 20% sulfuric acid solution, stir for 20 minutes, add 1 g of alkali lignin and 6 mL of deionized water, transfer to a reactor, keep warm at 118°C for 130 minutes, let it stand for 22 hours, and dry to obtain titanium dioxide composite nanoparticles; 2) Under a nitrogen atmosphere, 0.75 g of titanium dioxide composite nanoparticles, 0.6 g of lysine, and 15 mL of sodium hydroxide aqueous solution were mixed, the pH was adjusted to 11, the temperature was raised to 60°C, and a mixture of 0.5 mL of 40% glyoxal solution and 1.5 mL of deionized water was added. The mixture was kept warm for 3 h, cooled to 18°C, the pH was adjusted to 7, and the mixture was centrifuged at 10,000 rpm for 8 min. The mixture was dialyzed using a 1000 Da dialysis bag for 3 d and dried to obtain grafted titanium dioxide composite nanoparticles. 3) Under a nitrogen atmosphere, 1 g of grafted titanium dioxide composite nanoparticles and 8 g of N,N-dimethylformamide were mixed, the temperature was raised to 148°C, 4 mL of iodocyclohexane was added, and the mixture was kept warm for 11 h. The mixture was extracted three times with n-hexane, 5 mL of saturated sodium metabisulfite solution was added, and the mixture was filtered, washed, freeze-dried, and ground to obtain modified titanium dioxide composite nanoparticles. 4) 2.1 g of modified titanium dioxide composite nanoparticles, 0.8 g of boron-containing Schiff base flame retardant, and 40 mL of Tris-HCl buffer were mixed, ultrasonically stirred for 1 h, and heated to 30°C for 3 h to obtain composite titanium dioxide; The preparation of the boron-containing Schiff base flame retardant comprises the following steps: Mix 4.2 g of monoethanolamine borate and 100 mL of anhydrous ethanol, add 5.5 g of 2,4-dihydroxybenzaldehyde, stir at 18°C for 12 h, filter under reduced pressure, wash, and dry to obtain a boron-containing Schiff base flame retardant; S2: mixing composite titanium dioxide, dialdehyde chitosan, modified gelatin, deionized water, and acetic acid to obtain a protective impregnation solution; Deionized water was used as the solvent, and the composition of the protective impregnation solution was: 6 g / L composite titanium dioxide, 18 g / L dialdehyde chitosan, 36 g / L modified gelatin, and 2 g / L acetic acid; The preparation of the modified gelatin comprises the following steps: 1 g of gelatin and 100 mL of deionized water were mixed and dissolved in a 48°C water bath. 0.2 g of ε-polylysine and 10 U of microbial transglutaminase were added. The mixture was incubated for 11 h, then heated to 95°C in a water bath for 5 min. The mixture was dialyzed using a 10 KDa dialysis bag for 3 days and freeze-dried to obtain the modified gelatin. The mass ratio of the sum of the mass of composite titanium dioxide and dialdehyde chitosan to the mass of modified gelatin is 2:3; S3: The foam sponge is cleaned and dried, and then immersed in a protective impregnation liquid for immersion treatment, taken out and dried to obtain an anti-aging foam sponge material; the working conditions of the immersion treatment are: temperature 25° C., time 4 minutes.

[0021] Example 2: A method for preparing an anti-aging foam sponge material, comprising the following steps: S1: Prepare a foam sponge using composite titanium dioxide, gelatin, and polyvinyl alcohol as raw materials; The preparation of the foaming sponge comprises the following steps: 20 g of polyvinyl alcohol and 200 mL of deionized water were mixed, heated to 90°C and kept warm for 25 min, a mixture of 5 g of gelatin and 10 mL of deionized water was added, stirred at 700 rpm for 60 min, cooled to 65°C, 2 g of composite titanium dioxide and 20 g of 8 mol / L sulfuric acid were added in sequence, stirred for 6 min, 14 mL of emulsifier OP-10 was added, stirred and foamed for 7.5 min, 32 mL of formaldehyde solution with a mass concentration of 37% was added, the mixture was transferred to a mold, and kept warm at 60°C for 5.5 h to obtain a foamed sponge; The preparation of the composite titanium dioxide comprises the following steps: 1) Mix 60 mL of anhydrous ethanol and 20 mL of butyl titanate, add 4 mL of 20% sulfuric acid solution, stir for 25 minutes, add 1 g of alkali lignin and 6 mL of deionized water, transfer to a reactor, keep warm at 119°C for 120 minutes, let stand for 23 hours, and dry to obtain titanium dioxide composite nanoparticles; 2) Under a nitrogen atmosphere, 0.75 g of titanium dioxide composite nanoparticles, 0.6 g of lysine, and 15 mL of sodium hydroxide aqueous solution were mixed, the pH was adjusted to 11, the temperature was raised to 59°C, and a mixture of 0.5 mL of 40% glyoxal solution and 1.5 mL of deionized water was added. The mixture was kept warm for 3.5 h, cooled to 20°C, the pH was adjusted to 7.2, and the mixture was centrifuged at 10,000 rpm for 9 min. The mixture was dialyzed using a 1000 Da dialysis bag for 3 d and dried to obtain grafted titanium dioxide composite nanoparticles. 3) Under a nitrogen atmosphere, 1 g of grafted titanium dioxide composite nanoparticles and 8 g of N,N-dimethylformamide were mixed, the temperature was raised to 149°C, 4 mL of iodocyclohexane was added, and the mixture was kept warm for 11.5 h. The mixture was extracted four times with n-hexane, 5 mL of saturated sodium metabisulfite solution was added, and the mixture was filtered, washed, freeze-dried, and ground to obtain modified titanium dioxide composite nanoparticles. 4) 2.1 g of modified titanium dioxide composite nanoparticles, 0.8 g of boron-containing Schiff base flame retardant, and 40 mL of Tris-HCl buffer were mixed, ultrasonically stirred for 1.5 h, and heated to 35 °C for 2.5 h to obtain composite titanium dioxide; The preparation of the boron-containing Schiff base flame retardant comprises the following steps: Mix 4.2 g of monoethanolamine borate and 100 mL of anhydrous ethanol, add 5.5 g of 2,4-dihydroxybenzaldehyde, stir at 20° C. for 11.5 h, filter under reduced pressure, wash, and dry to obtain a boron-containing Schiff base flame retardant; S2: mixing composite titanium dioxide, dialdehyde chitosan, modified gelatin, deionized water, and acetic acid to obtain a protective impregnation solution; Using deionized water as solvent, the composition of the protective impregnation solution is: 7g / L composite titanium dioxide, 18g / L dialdehyde chitosan, 37.5g / L modified gelatin, and 2g / L acetic acid; The preparation of the modified gelatin comprises the following steps: 1 g of gelatin and 100 mL of deionized water were mixed and dissolved in a 50°C water bath. 0.2 g of ε-polylysine and 10 U of microbial transglutaminase were added. The mixture was incubated for 11.5 h, heated to 95°C in a water bath for 5.5 min, dialyzed using a 10 KDa dialysis bag for 3 days, and freeze-dried to obtain modified gelatin. The mass ratio of the sum of the mass of composite titanium dioxide and dialdehyde chitosan to the mass of modified gelatin is 2:3; S3: The foam sponge is cleaned and dried, and then immersed in a protective impregnation liquid for immersion treatment, taken out and dried to obtain an anti-aging foam sponge material; the working conditions of the immersion treatment are: temperature 28° C., time 3 minutes.

[0022] Example 3: A method for preparing an anti-aging foam sponge material, comprising the following steps: S1: Prepare a foam sponge using composite titanium dioxide, gelatin, and polyvinyl alcohol as raw materials; The preparation of the foaming sponge comprises the following steps: 20 g of polyvinyl alcohol and 200 mL of deionized water were mixed, heated to 95°C and kept warm for 20 min, a mixture of 5 g of gelatin and 10 mL of deionized water was added, stirred at 700 rpm for 65 min, cooled to 67°C, 2 g of composite titanium dioxide and 20 g of 8 mol / L sulfuric acid were added in sequence, stirred for 7 min, 14 mL of emulsifier OP-10 was added, stirred and foamed for 8 min, 32 mL of 37% formaldehyde solution was added, the mixture was transferred to a mold, and kept warm at 60°C for 6 h to obtain a foamed sponge; The preparation of the composite titanium dioxide comprises the following steps: 1) Mix 60 mL of anhydrous ethanol and 20 mL of butyl titanate, add 4 mL of 20% sulfuric acid solution, stir for 30 minutes, add 1 g of alkali lignin and 6 mL of deionized water, transfer to a reactor, keep at 120°C for 110 minutes, let it stand for 24 hours, and dry to obtain titanium dioxide composite nanoparticles; 2) Under nitrogen atmosphere, 0.75 g titanium dioxide composite nanoparticles, 0.6 g lysine, and 15 mL sodium hydroxide aqueous solution were mixed, the pH was adjusted to 11, the temperature was raised to 60°C, 0.5 mL of 40% glyoxal solution and 1.5 mL of deionized water were added, the mixture was kept warm for 4 h, cooled to 25°C, the pH was adjusted to 7.5, centrifuged at 10,000 rpm for 10 min, dialyzed with a 1000 Da dialysis bag for 3 d, and dried to obtain grafted titanium dioxide composite nanoparticles; 3) Under a nitrogen atmosphere, 1 g of grafted titanium dioxide composite nanoparticles and 8 g of N,N-dimethylformamide were mixed, the temperature was raised to 150°C, 4 mL of iodocyclohexane was added, and the mixture was kept warm for 12 h. The mixture was extracted five times with n-hexane, 5 mL of saturated sodium metabisulfite solution was added, and the mixture was filtered, washed, freeze-dried, and ground to obtain modified titanium dioxide composite nanoparticles. 4) 2.1 g of modified titanium dioxide composite nanoparticles, 0.8 g of boron-containing Schiff base flame retardant, and 40 mL of Tris-HCl buffer were mixed, ultrasonically stirred for 2 h, and heated to 40 °C for 2 h to obtain composite titanium dioxide; The preparation of the boron-containing Schiff base flame retardant comprises the following steps: Mix 4.2 g of monoethanolamine borate and 100 mL of anhydrous ethanol, add 5.5 g of 2,4-dihydroxybenzaldehyde, stir at 25°C for 11 h, filter under reduced pressure, wash, and dry to obtain a boron-containing Schiff base flame retardant; S2: mixing composite titanium dioxide, dialdehyde chitosan, modified gelatin, deionized water, and acetic acid to obtain a protective impregnation solution; Deionized water was used as the solvent, and the composition of the protective impregnation solution was: 8 g / L composite titanium dioxide, 18 g / L dialdehyde chitosan, 39 g / L modified gelatin, and 2 g / L acetic acid; The preparation of the modified gelatin comprises the following steps: 1 g of gelatin and 100 mL of deionized water were mixed and dissolved in a 52°C water bath. 0.2 g of ε-polylysine and 10 U of microbial transglutaminase were added. The mixture was incubated for 12 h, then heated to 95°C in a water bath for 6 min. The mixture was dialyzed using a 10 KDa dialysis bag for 3 days and freeze-dried to obtain the modified gelatin. The mass ratio of the sum of the mass of composite titanium dioxide and dialdehyde chitosan to the mass of modified gelatin is 2:3; S3: The foam sponge is cleaned and dried, and then immersed in a protective impregnation liquid for immersion treatment, taken out and dried to obtain an anti-aging foam sponge material; the working conditions of the immersion treatment are: temperature 30° C., time 2 minutes.

[0023] Comparative Example 1: Taking Example 3 as the control group, titanium dioxide composite nanoparticles were used to replace composite titanium dioxide, and other processes were normal.

[0024] Comparative Example 2: Taking Example 3 as the control group, the mass ratio of the sum of the mass of composite titanium dioxide and dialdehyde chitosan to the modified gelatin is 2:2, that is, the modified gelatin is 26 g / L, and other processes are normal.

[0025] In the embodiments and comparative examples: The preparation of dialdehyde chitosan comprises the following steps: Mix 2.5 g of chitosan and 100 mL of 1% glacial acetic acid solution, stir for 3 h, add 1.6 g of sodium periodate, stir in the dark for 3 h, add 10 mL of 0.1 mol / L ethylene glycol solution, pour into a dialysis bag, dialyze with deionized water for 3 days, and freeze-dry to obtain dialdehyde chitosan.

[0026] Sources of raw materials used (for demonstration purposes only): Alkali lignin 471003: Sigma-Aldrich (Shanghai) Trading Co., Ltd.; ε-polylysine (99%): Shandong Pingju Biotechnology Co., Ltd.; Monoethanolamine borate (99%): Nantong Runfeng Petrochemical Co., Ltd.; Lysine S20049: Shanghai Yuanye Biotechnology Co., Ltd.; Chitosan C105799, Gelatin G108394, Polyvinyl alcohol P139540, Ethylene glycol E103319, Emulsifier OP-10O304931 , formaldehyde F111939, butyl titanate T104104, glyoxal G299082, iodocyclohexane I157579, Tris-HCl buffer T301507, 2,4-dihydroxybenzaldehyde D106474, gelatin G108394, transglutaminase T777729: Aladdin reagent; sulfuric acid, anhydrous ethanol, sodium hydroxide, N,N-dimethylformamide, n-hexane, sodium periodate, sodium metabisulfite, acetic acid, analytical grade, commercially available.

[0027] Performance testing: Performance test: The sponges prepared in the examples and comparative examples were subjected to performance tests: Compressive Strength: Compression testing was conducted at 25°C using a universal testing machine. Cylindrical specimens with a diameter of 20 mm and a thickness of 10 mm were cut and compressed at a rate of 2 mm / min. The test was stopped when the specimens were compressed to 15% of their original height. Flame Retardancy: UL-94 vertical burning rating testing was performed. Antibacterial Properties: The oscillation method in GB / T20944-2008 was used for determination. Staphylococcus aureus was selected as the test bacteria. The sponges were washed with standard water 10 times and then dried before testing. Aging Resistance: The compressive strength was tested again after irradiation with 365 nm ultraviolet light for 72 hours. The compressive strength was then compared to the unirradiated sponge. Sponges with a compressive strength change rate of less than 1% (inclusive) were considered qualified; otherwise, they were considered unqualified. The results are shown in Table 1. Table 1

[0028] The present invention provides an anti-aging foam sponge material and a preparation method thereof. By optimizing the composition and process, a foam sponge material with good mechanical strength, antibacterial properties, flame retardancy, and anti-aging properties is prepared. In Table 1, / indicates that the item was not tested.

[0029] By comparing Example 3 with Comparative Example 1, it can be seen that when preparing the foam sponge with polyvinyl alcohol as the raw material, the degradable and green biomass material gelatin is introduced to improve the mechanical strength of the matrix without affecting the pore structure of the matrix. In order to further improve the light and heat aging resistance of the sponge foaming material, titanium dioxide and lignin are introduced into the foam sponge as anti-aging agents. In order to improve the uniformity of the dispersion of titanium dioxide and lignin in the foam sponge and improve the uniformity of the material, alkali lignin is used as a biological template inducer to synthesize titanium dioxide composite nanoparticles with good UV shielding properties by a hydrothermal method. The particles are then grafted with lysine with antibacterial properties through the Mannich reaction, and then subjected to in-situ demethylation modification to obtain modified titanium dioxide composite nanoparticles with multiple functional groups having carboxyl, aldehyde, and catechol structures. The catechol structure is then used to graft a boron-containing Schiff base flame retardant prepared with monoethanolamine borate and 2,4-dihydroxybenzaldehyde as raw materials to obtain a composite titanium dioxide containing both borate bonds and Schiff base dynamic bonds, aldehyde groups, carboxyl groups and other multiple active sites, thereby improving the bonding strength between the composite titanium dioxide and the foam sponge and giving the sponge excellent flame retardancy and shape retention.

[0030] By comparing Example 3 with Comparative Example 2, it can be seen that in order to further improve the antibacterial property of the foamed sponge and solve the problem of possible residual free aldehyde during sponge foaming, the present invention prepares a protective impregnation solution by mixing composite titanium dioxide, dialdehyde chitosan, modified gelatin, deionized water, and acetic acid, wherein the modified gelatin uses gelatin as a raw material and glutamine transaminase as a catalyst, and grafts ε-polylysine with biocompatibility, biodegradability, and antibacterial properties onto the gelatin peptide chain to increase the free amino groups available for reaction in the gelatin molecules. By controlling the mass ratio of the sum of the masses of composite titanium dioxide and dialdehyde chitosan to the modified gelatin, a complex cross-linked network is constructed to obtain an antibacterial, flame retardant, and anti-aging foamed sponge material.

[0031] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structural transformations made using the present invention specification under the inventive concept of the present invention, or any direct / indirect application in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A method for preparing an anti-aging foam sponge material, characterized in that: The following steps are involved: S1: Prepare a foam sponge using composite titanium dioxide, gelatin, and polyvinyl alcohol as raw materials; S2: mixing composite titanium dioxide, dialdehyde chitosan, modified gelatin, deionized water, and acetic acid to obtain a protective impregnation solution; S3: cleaning and drying the foamed sponge, then immersing the foamed sponge in a protective impregnation liquid for immersion treatment, taking it out and drying it to obtain an anti-aging foamed sponge material.

2. The method for preparing an anti-aging foam sponge material according to claim 1, characterized in that: The working conditions of the immersion treatment are: temperature of 25-30°C and time of 2-4 minutes.

3. The method for preparing an anti-aging foam sponge material according to claim 1, characterized in that: The preparation of the foaming sponge comprises the following steps: Mix polyvinyl alcohol and deionized water, heat to 85-95°C and keep warm for 20-30 minutes, add a mixture of gelatin and deionized water, stir for 55-65 minutes, cool to 63-67°C, add composite titanium dioxide and sulfuric acid in sequence, stir for 5-7 minutes, add emulsifier OP-10, stir and foam for 7-8 minutes, add formaldehyde solution, transfer to a mold, and keep warm at 60°C for 5-6 hours to obtain a foamed sponge.

4. The method for preparing an anti-aging foam sponge material according to claim 3, characterized in that: The usage ratio of composite titanium dioxide, gelatin, polyvinyl alcohol and formaldehyde is 2g:5g:20g:32mL.

5. The method for preparing an anti-aging foam sponge material according to claim 1, characterized in that: Deionized water was used as the solvent, and the composition of the protective impregnation solution was: (6-8) g / L composite titanium dioxide, 18 g / L dialdehyde chitosan, (36-39) g / L modified gelatin, and 2 g / L acetic acid.

6. The method for preparing an anti-aging foam sponge material according to claim 1, characterized in that: In the protective impregnation solution, the mass ratio of the sum of the mass of composite titanium dioxide and dialdehyde chitosan to the mass of modified gelatin is 2:

3.

7. The method for preparing an anti-aging foam sponge material according to claim 1, characterized in that: The preparation of the modified gelatin comprises the following steps: Mix gelatin and deionized water, dissolve in a 48-52°C water bath, add ε-polylysine, add transglutaminase, keep warm for 11-12 hours, heat to 95°C water bath for 5-6 minutes, dialyze for 3 days, and freeze-dry to obtain modified gelatin.

8. The method for preparing an anti-aging foam sponge material according to claim 1, characterized in that: The preparation of the composite titanium dioxide comprises the following steps: 1) Anhydrous ethanol and butyl titanate were mixed, sulfuric acid solution was added, and the mixture was stirred for 20-30 minutes. A mixed solution of alkali lignin and deionized water was added, and the mixture was transferred to a reactor, kept at 118-120°C for 110-130 minutes, allowed to stand for 22-24 hours, and dried to obtain titanium dioxide composite nanoparticles; 2) Under a nitrogen atmosphere, titanium dioxide composite nanoparticles, lysine, and a sodium hydroxide aqueous solution were mixed, the pH was adjusted to 11, the temperature was raised to 58-60°C, a mixture of glyoxal solution and deionized water was added, the temperature was kept for 3-4 hours, the mixture was cooled to 18-25°C, the pH was adjusted to 7-7.5, the mixture was centrifuged, dialyzed for 3 days, and dried to obtain grafted titanium dioxide composite nanoparticles; 3) Under a nitrogen atmosphere, the grafted titanium dioxide composite nanoparticles and N,N-dimethylformamide are mixed, the temperature is raised to 148-150°C, iodocyclohexane is added, the temperature is kept for 11-12 hours, and the mixture is extracted 3-5 times with n-hexane as an extractant. A saturated sodium metabisulfite solution is added, and the mixture is filtered, washed, freeze-dried, and ground to obtain modified titanium dioxide composite nanoparticles; 4) The modified titanium dioxide composite nanoparticles, the boron-containing Schiff base flame retardant, and the Tris-HCl buffer were mixed, ultrasonically stirred for 1-2 hours, and heated to 30-40° C. and kept warm for 2-3 hours to obtain composite titanium dioxide.

9. The method for preparing an anti-aging foam sponge material according to claim 8, characterized in that: The preparation of the boron-containing Schiff base flame retardant comprises the following steps: Mix monoethanolamine borate and anhydrous ethanol, add 2,4-dihydroxybenzaldehyde, stir at 18-25° C. for 11-12 hours, filter under reduced pressure, wash, and dry to obtain a boron-containing Schiff base flame retardant.

10. An anti-aging foam sponge material, characterized in that: Prepared according to the preparation method according to any one of claims 1 to 9.

Images