A bioactive sustained-release polyurethane memory foam and its preparation method

Abstract

This invention discloses a bioactive slow-release polyurethane memory foam and its preparation method, relating to the field of polyurethane memory foam technology. The bioactive slow-release polyurethane memory foam comprises the following raw materials in parts by weight: 80-90 parts polyether polyol, 4-6 parts hydroxyapatite, 0.3-0.5 parts catalyst, 0.5-1 part dispersant, 6-10 parts deionized water, 1.5-2 parts foam stabilizer, 1-2 parts antibacterial agent, 0.5-1 part anti-aging agent, and 45-55 parts diphenylmethane diisocyanate. The polyurethane memory foam prepared by this invention exhibits excellent tensile properties, anti-aging properties, antibacterial properties, far-infrared emission properties, and slow rebound properties.

Description

Technical Field

[0001] This invention relates to the field of polyurethane memory foam technology, specifically to a bioactive sustained-release polyurethane memory foam and its preparation method. Background Technology

[0002] Polyurethane memory foam, due to its excellent slow rebound properties, good conformability and support, and comfortable pressure dispersion capabilities, is widely used in functional pillows, mattresses, and medical care products in the healthy home sector. However, traditional polyurethane memory foam materials have an open pore structure and a large specific surface area, making them prone to absorbing sweat and moisture. Over long-term use, this can easily lead to bacterial and mold growth, producing odors and causing material aging, affecting hygiene and safety. Furthermore, its function is mainly limited to passive support and cushioning, lacking active health-regulating capabilities such as regulating microcirculation, relieving fatigue, and improving sleep quality, making it difficult to meet the current demand for a balance between comfort and functionality in healthy home products. In existing technologies, the antibacterial function of memory foam largely relies on physically blended antibacterial agents or inorganic silver-based materials, which suffer from problems such as short-lasting antibacterial effects, easy migration and precipitation, and insufficient stability. Far-infrared therapy functions are mostly concentrated in functional fibers or coated fabrics, which have poor compatibility with polyurethane foam systems, making it difficult to achieve integrated molding and long-term sustained-release stability with memory foam materials. Hydroxyapatite, a natural bioactive material highly similar to the composition of human bones and teeth, possesses excellent biocompatibility and far-infrared radiation capabilities. Its far-infrared emission band highly matches the absorption band of human microcirculation, and it has already found applications in functional fibers and physiotherapy materials. However, current technology has not effectively incorporated the bioactivity and far-infrared function of hydroxyapatite into polyurethane memory foam systems, and an integrated, slow-release bioactive memory foam material suitable for functional pillows and health bedding has not yet been developed. Therefore, developing a polyurethane memory foam that incorporates nano-sized hydroxyapatite into a polyurethane foam system and simultaneously possesses excellent antibacterial, anti-aging, mechanical, and slow-rebound properties has significant application value.

[0003] Chinese invention patent CN111440283A discloses an antibacterial modified polyurethane memory foam and its preparation method, which includes: mixing polyether polyol, isocyanate, foaming agent, catalyst, stabilizer and silver dispersion to obtain a first mixture; mixing silica sol finishing liquid and far-infrared additives to obtain a second mixture; and mixing the first mixture and the second mixture and injecting the mixture into a mold. While the antibacterial effect of the polyurethane memory foam is improved through the synergistic effect of nano-silver particles and far-infrared rays, its anti-aging properties are still insufficient. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a bioactive sustained-release polyurethane memory foam and its preparation method.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A bioactive, sustained-release polyurethane memory foam comprises the following raw materials in parts by weight: 80-90 parts of polyether polyol, 4-6 parts of hydroxyapatite, 0.3-0.5 parts of catalyst, 0.5-1 part of dispersant, 6-10 parts of deionized water, 1.5-2 parts of foam stabilizer, 1-2 parts of antibacterial agent, 0.5-1 part of anti-aging agent, and 45-55 parts of diphenylmethane diisocyanate; The anti-aging agent is prepared by the following method: S1: 2-Mercaptomethylbenzimidazole reacts with methyl acrylate to generate intermediate 1; the reaction equation is shown below. S2: 2-(2,5,8,11-tetraoxadodecyl)ethylene oxide reacts with 4,4'-diaminodiphenylamine to form intermediate 2; the reaction equation is shown below: S3: Intermediate 1 reacts with intermediate 2 to generate an anti-aging agent.

[0006] The reaction equation is shown below: In step S1, the molar ratio of 2-mercaptomethylbenzimidazole to methyl acrylate is 1:(1.02-1.04).

[0007] In step S2, the molar ratio of 2-(2,5,8,11-tetraoxadodecyl)ethylene oxide to 4,4'-diaminodiphenylamine is (2.01-2.03):1.

[0008] In step S3, the molar ratio of intermediate 1 to intermediate 2 is (2.03-2.05):1.

[0009] The antibacterial agent is prepared by the following method: N1: 9-Octadecan-1-amine reacts with 4,5-dihydroxyphthalic acid to generate acetylated intermediate A; the reaction equation is shown below. N2: Acetylated intermediate A reacts with m-chloroperoxybenzoic acid to form acetylated intermediate B; the reaction equation is shown below. N3: Acetylated intermediate B reacts with 1-methyl-3-(3-aminopropyl)-3-chloroimidazolium to generate acetylated intermediate C; the reaction equation is shown below. N4: The acetylated intermediate C reacts with 4-[5-(methylsulfonyl)-1,3,4-oxadiazol-2-yl]benzoic acid to generate an antibacterial agent.

[0010] The reaction equation is shown below: In step N1, the molar ratio of 9-octadecene-1-amine to 4,5-dihydroxyphthalic acid is 2.05:1; in step N2, the molar ratio of acetylation intermediate A to m-chloroperoxybenzoic acid is 1:2.2; in step N3, the molar ratio of acetylation intermediate B to 1-methyl-3-(3-aminopropyl)-3-chloroimidazolium is 1:2.01; in step N4, the molar ratio of acetylation intermediate C to 4-[5-(methylsulfonyl)-1,3,4-oxadiazol-2-yl]benzoic acid is 1:2.1.

[0011] The catalyst is dibutyltin dilaurate.

[0012] The dispersant is modified silicone oil.

[0013] The foam stabilizer is DC-193 foam stabilizer.

[0014] A method for preparing a bioactive sustained-release polyurethane memory foam includes the following steps: (1) Weigh out the following by weight: 80-90 parts of polyether polyol, 4-6 parts of hydroxyapatite, 0.3-0.5 parts of catalyst, 0.5-1 parts of dispersant, 6-10 parts of deionized water, 1.5-2 parts of foam stabilizer, 1-2 parts of antibacterial agent, 0.5-1 parts of anti-aging agent, and 45-55 parts of diphenylmethane diisocyanate; (2) Mix polyether polyol, hydroxyapatite, catalyst, dispersant, deionized water, foam stabilizer, antibacterial agent and anti-aging agent, add diphenylmethane diisocyanate, stir, quickly pour into mold, and cure at room temperature to obtain bioactive slow-release polyurethane memory foam.

[0015] Due to the adoption of the above technical solutions, the beneficial effects of the present invention include: The polyurethane memory foam prepared by this invention exhibits excellent tensile properties, anti-aging properties, antibacterial properties, far-infrared emission properties, and slow rebound properties. The anti-aging agents added to the components used in preparing the polyurethane memory foam enhance its tensile and anti-aging properties through the synergistic effect of hindered amines, benzimidazoles, thioesters, and flexible ether chain multifunctional structural units. The added antibacterial agents contain imidazolium cations, long-chain alkyl groups, benzoxazole sulfones, catechol, and secondary amine structures, forming a synergistic antibacterial system. Attached Figure Description

[0016] Figure 1 The image shows the proton NMR spectrum of the anti-aging agent prepared in Example 1.

[0017] Figure 2 The image shows a high-resolution mass spectrum of the anti-aging agent prepared in Example 1.

[0018] Figure 3 The image shows the proton NMR spectrum of the antibacterial agent prepared in Example 4.

[0019] Figure 4 The image shows a high-resolution mass spectrum of the antibacterial agent prepared in Example 4. Detailed Implementation

[0020] The following description, in conjunction with specific embodiments, provides further details, but the present invention is not limited to these embodiments.

[0021] Example 1: Preparation of Anti-aging Agent S1: Under nitrogen protection, 150 ml of anhydrous tetrahydrofuran, 0.1 mol of 2-mercaptomethylbenzimidazole, 0.102 mol of methyl acrylate, and 0.5 g of 2,2-dimethoxy-2-phenylacetophenone were stirred and mixed. The mixture was then irradiated at 100 W under 365 nm UV light for 30 min at room temperature, followed by vacuum distillation at 40 °C for 2 h. 100 ml of cold anhydrous diethyl ether was added, and the mixture was stirred to precipitate. The precipitate was filtered, washed with 50 ml of cold anhydrous diethyl ether, and dried under vacuum at 40 °C for 12 h to obtain intermediate 1. Its 1H NMR spectrum is as follows: 1 H NMR (400 MHz, DMSO-d6) δ 12.25 (s, 1H), 7.52 (d, J = 5.5 Hz, 1H), 7.40 (d, J = 6.1 Hz, 1H), 7.19 (d, J = 7.8 Hz, 2H), 3.82 (s, 2H), 3.66 (s, 3H), 3.04-2.81 (m, 2H), 2.62(t, J = 6.8 Hz, 2H); HRMS (m / z):251.0781[M+H] + ; S2: Under nitrogen protection, 400 ml of anhydrous ethanol, 0.1 mol of 4,4'-diaminodiphenylamine, 0.201 mol of 2-(2,5,8,11-tetraoxadodecyl)ethylene oxide, and 0.205 mol of triethylamine were stirred and mixed. The mixture was heated to 55 °C and reacted for 6 h. After cooling to room temperature, the mixture was filtered, and then distilled under reduced pressure at 50 °C for 1 h. 250 ml of cold n-hexane was added and stirred to precipitate the solid. The precipitate was filtered, and the filter cake was washed with cold n-hexane (3 × 50 ml). The solid was then dried under vacuum at 50 °C for 8 h to obtain intermediate 2. Its 1H NMR data are as follows: 1H NMR (400 MHz, Chloroform-d) δ 7.05 (s, 1H), 7.02-6.95 (m, 4H), 6.60-6.52 (m, 4H), 5.14 (d,J = 5.6 Hz, 2H), 3.99 (d, J = 5.0 Hz, 2H), 3.85 HRMS (m / z):640.3735[M+H] + ; S3: Under nitrogen protection, 550 ml of xylene, 0.203 mol of intermediate 1, 0.1 mol of intermediate 2, and 0.02 mol of dibutyltin oxide were stirred and mixed, and the mixture was refluxed for 8 h (methanol was removed using a water separator during the reaction). After cooling to room temperature, the mixture was washed with saturated brine (3 × 150 ml), dried with 30 g of anhydrous magnesium sulfate, filtered, distilled under reduced pressure at 70 °C for 1 h, and dried under vacuum at 70 °C for 12 h to obtain the anti-aging agent; its proton NMR spectrum is shown below. Figure 1 As shown, the proton NMR data are as follows: 1 ¹H NMR (400 MHz, DMSO-d⁶) δ 12.25 (s, 2H), 8.28 (s, 1H), 7.52 (d, J = 5.5 Hz, 2H), 7.40 (d, J = 5.6 Hz, 2H), 7.19 (d, J = 11.8 Hz, 4H), 7.06–6.98 (m, 4H), 6.68–6.60 (m, 4H), 5.74 (s, 2H), 4.75 (s, 2H), 3.84–3.33 (m, 36H), 3.30 (s, 6H), 2.98–2.81 (m, 4H), 2.65–2.53 (m, 4H); its high-resolution mass spectrum is shown below. Figure 2 As shown, the mass spectrometry data are as follows: HRMS (m / z): 1076.4756 [M+H] + .

[0022] Example 2 Preparation of Anti-aging Agent S1: Under nitrogen protection, 150 ml of anhydrous tetrahydrofuran, 0.1 mol of 2-mercaptomethylbenzimidazole, 0.103 mol of methyl acrylate, and 0.5 g of 2,2-dimethoxy-2-phenylacetophenone were stirred and mixed. The mixture was then irradiated with 100 W of 365 nm ultraviolet light for 30 min at room temperature, followed by vacuum distillation at 40 °C for 2 h. 100 ml of cold anhydrous diethyl ether was added, and the mixture was stirred to precipitate the precipitate. The precipitate was filtered, washed with 50 ml of cold anhydrous diethyl ether, and dried under vacuum at 40 °C for 12 h to obtain intermediate 1. S2: Under nitrogen protection, 400 ml of anhydrous ethanol, 0.1 mol of 4,4'-diaminodiphenylamine, 0.202 mol of 2-(2,5,8,11-tetraoxadodecyl)ethylene oxide, and 0.205 mol of triethylamine were stirred and mixed. The mixture was heated to 60 °C and reacted for 5 h. After cooling to room temperature, the mixture was filtered and distilled under reduced pressure at 50 °C for 1 h. 250 ml of cold n-hexane was added and stirred to precipitate the precipitate. The precipitate was filtered, washed with cold n-hexane (3 × 50 ml), and dried under vacuum at 50 °C for 8 h to obtain intermediate 2. S3: Under nitrogen protection, 550 ml of xylene, 0.204 mol of intermediate 1, 0.1 mol of intermediate 2, and 0.02 mol of dibutyltin oxide were stirred and mixed, and the mixture was refluxed for 8 h (methanol was removed by a water separator during the reaction). After cooling to room temperature, the mixture was washed with saturated brine (3 × 150 ml), dried with 30 g of anhydrous magnesium sulfate, filtered, distilled under reduced pressure at 70 °C for 1 h, and dried under vacuum at 70 °C for 12 h to obtain the anti-aging agent.

[0023] Example 3 Preparation of Anti-aging Agent S1: Under nitrogen protection, 150 ml of anhydrous tetrahydrofuran, 0.1 mol of 2-mercaptomethylbenzimidazole, 0.104 mol of methyl acrylate, and 0.5 g of 2,2-dimethoxy-2-phenylacetophenone were stirred and mixed. The mixture was then irradiated with 100 W of 365 nm ultraviolet light for 30 min at room temperature, followed by vacuum distillation at 40 °C for 2 h. 100 ml of cold anhydrous diethyl ether was added, and the mixture was stirred to precipitate the precipitate. The precipitate was filtered, washed with 50 ml of cold anhydrous diethyl ether, and dried under vacuum at 40 °C for 12 h to obtain intermediate 1. S2: Under nitrogen protection, 400 ml of anhydrous ethanol, 0.1 mol of 4,4'-diaminodiphenylamine, 0.203 mol of 2-(2,5,8,11-tetraoxadodecyl)ethylene oxide, and 0.205 mol of triethylamine were stirred and mixed. The mixture was heated to 65 °C and reacted for 4 h. After cooling to room temperature, the mixture was filtered and distilled under reduced pressure at 50 °C for 1 h. 250 ml of cold n-hexane was added and stirred to precipitate the precipitate. The precipitate was filtered, washed with cold n-hexane (3 × 50 ml), and dried under vacuum at 50 °C for 8 h to obtain intermediate 2. S3: Under nitrogen protection, 550 ml of xylene, 0.205 mol of intermediate 1, 0.1 mol of intermediate 2, and 0.02 mol of dibutyltin oxide were stirred and mixed, and the mixture was refluxed for 8 h (methanol was removed by a water separator during the reaction). After cooling to room temperature, the mixture was washed with saturated brine (3 × 150 ml), dried with 30 g of anhydrous magnesium sulfate, filtered, distilled under reduced pressure at 70 °C for 1 h, and dried under vacuum at 70 °C for 12 h to obtain the anti-aging agent.

[0024] Example 4 Preparation of antibacterial agent N1: Mix 100 ml acetic anhydride, 4 ml pyridine, and 0.1 mol 4,5-dihydroxyphthalic acid. Stir and react at room temperature for 24 h in the dark. Distill under reduced pressure at 50 °C for 3 h. Add 60 ml deionized water, allow to stand to precipitate, filter, wash the filter cake with ice water (3 × 10 ml), and then dilute with a mixture of 100 ml ethyl acetate and n-hexane (V... 乙酸乙酯 :V 正己烷 Recrystallization of acetylated 4,5-dihydroxyphthalic acid (1:5) was performed, followed by vacuum drying at 60°C for 12 h to obtain acetylated 4,5-dihydroxyphthalic acid. Under nitrogen protection, 750 ml of anhydrous dichloromethane, 0.1 mol of acetylated 4,5-dihydroxyphthalic acid, 45.8 g of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, and 25.2 g of N-hydroxysuccinimide were stirred and mixed. 0.205 mol of 9-octadecene-1-amine was added, and the mixture was reacted at room temperature for 12 h. After filtration, the mixture was distilled under reduced pressure at 30°C for 1 h. The crude product was purified by silica gel chromatography (V... 二氯甲烷 :V 甲醇 The ratio of the distillation solution to that of intermediate A was 10:1. The intermediate was distilled under reduced pressure at 30°C for 1 hour to obtain acetylated intermediate A. Its 1H NMR data are as follows: 1 H NMR (400 MHz, DMSO-d6) δ 8.36 (s, 2H), 7.47 (s,2H), 5.37 (t, J = 5.1 Hz, 4H), 3.29 (d, J = 5.6 Hz, 4H), 2.30 (s, 6H), 2.00(m, 8H), 1.59 (m, 4H), 1.36-1.25 (m, 44H), 0.89 (t, J = 6.3 Hz, 6H); HRMS (m / z):781.6014[M+H] + ; Under nitrogen protection, 500 ml of anhydrous dichloromethane and 0.1 mol of acetylation intermediate A were stirred and mixed thoroughly. Under ice bath conditions, 0.22 mol of m-chloroperoxybenzoic acid was added, and the mixture was stirred for 30 min. The temperature was then raised to 25 °C and reacted for 4 h. The reaction solution was washed successively with 200 ml of saturated sodium sulfite solution and 200 ml of saturated sodium bicarbonate solution, dried over 30 g of anhydrous magnesium sulfate, filtered, and distilled under reduced pressure at 30 °C for 1 h to obtain acetylation intermediate B. Its 1H NMR data are as follows: 1 H NMR (400 MHz, DMSO-d6) δ 8.36 (s, 2H),7.47 (s, 2H), 3.41 (m, 4H), 3.29 (dd, J = 2.9, 3.5 Hz, 4H), 2.30 (s, 6H),1.76 (d, J = 12.4 Hz, 4H), 1.65-1.57 (m, 8H), 1.41-1.25 (m, 44H), 0.89 (t, J= 6.4 Hz, 6H); HRMS (m / z):813.5917[M+H] + ; N3: Under nitrogen protection, 600 ml of anhydrous toluene, 0.1 mol of acetylated intermediate B, and 0.201 mol of 1-methyl-3-(3-aminopropyl)-3-chloroimidazolium were stirred and mixed, and the mixture was heated to 80 °C and reacted for 6 h. The mixture was washed with deionized water (2 × 150 ml), dried with 30 g of anhydrous magnesium sulfate, filtered, and distilled under reduced pressure at 60 °C for 1 h. The final product was obtained by distillation using a mixed solution of dichloromethane and n-hexane (V... 二氯甲烷 :V 正己烷 Recrystallize (7:3 ratio), filter, and dry under vacuum at 50°C for 8 hours to obtain acetylated intermediate C; its 1H NMR data are as follows: 1H NMR (400 MHz, Chloroform-d) δ 9.54 (s, 2H), 7.99 (d, J = 7.6 Hz,4H), 7.50 (s, 2H), 7.41 (s, 2H), 4.38 (m, 4H), 3.90 (s, 6H), 3.55 (s, 2H),3.53 (s, 2H), 3.32 (m, 4H), 3.04 (d, J = 5.5 Hz, 2H), 2.85-2.73 (m, 4H), 2.72(d, J = 6.5 Hz, 2H), 2.38 (s, 6H), 2.27 (d, J = 4.9 Hz, 4H), 1.61-1.24 (m,56H), 0.90 (t, J = 6.3 Hz, 6H); HRMS (m / z):546.4143[M-2Cl] 2+ ; Under nitrogen protection, 1000 ml of anhydrous tetrahydrofuran, 0.21 mol of 4-[5-(methylsulfonyl)-1,3,4-oxadiazol-2-yl]benzoic acid, 0.21 mol of dicyclohexylcarbodiimide, and 0.04 mol of 4-dimethylaminopyridine were mixed and stirred for 15 min. 0.1 mol of acetylated intermediate C was added, and the mixture was reacted at 25 °C for 18 h. After filtration, 200 ml of saturated sodium bicarbonate solution was added and stirred for 30 min. Then, 100 ml of 20 wt% ammonia in methanol solution was added, and the mixture was reacted at room temperature for 12 h. The mixture was then distilled under reduced pressure at 40 °C for 2 h. 650 ml of cold diethyl ether was added, and the mixture was stirred to precipitate the precipitate. After filtration, the precipitate was washed with ice water (3 × 80 ml) and then with a mixture of 600 ml of ethyl acetate and n-hexane (V... 乙酸乙酯 :V 正己烷 Recrystallization of a 1:5 mixture was performed, followed by vacuum drying at 60°C for 12 hours to obtain the antibacterial agent; its proton NMR spectrum is shown below. Figure 3 As shown, the proton NMR data are as follows: 1H NMR (400 MHz, Chloroform-d) δ 9.54 (s, 2H), 8.19-8.11 (m,4H), 8.09-8.02 (m, 4H), 8.00 (s, 2H), 7.92 (d, J = 5.6 Hz, 2H), 7.72 (s, 2H),7.50 (s, 2H), 5.25 (s, 2H), 4.71 (s, 2H), 4.38 (s, 4H), 3.90 (s, 6H), 3.39(d, J = 6.5 Hz, 2H), 3.36 (s, 6H), 3.32 (s, 4H), 2.88 (d, J = 5.5 Hz, 2H),2.79 (qd, J = 12.4, 4.5 Hz, 4H), 2.27 (d, J = 4.9 Hz, 4H), 1.89–1.71 (m, 4H), 1.62–1.26 (m, 52H), 0.90 (t, J = 6.5 Hz, 6H); its high-resolution mass spectrum is shown below. Figure 4 The mass spectrometry data are as follows: HRMS (m / z): 754.4086 [M-2Cl] 2+ .

[0025] Example 5: Preparation of Bioactive Sustained-Release Polyurethane Memory Foam (1) Weigh the following by weight: 80g polyether polyol, 4g hydroxyapatite, 0.3g catalyst (dibutyltin dilaurate), 0.5g dispersant (modified silicone oil), 6g deionized water, 1.5g foam stabilizer (DC-193 foam stabilizer), 1g antibacterial agent (prepared in Example 4), 0.5g antiaging agent (prepared in Example 1), and 45g diphenylmethane diisocyanate; (2) Mix polyether polyol, hydroxyapatite, catalyst, dispersant, deionized water, foam stabilizer, antibacterial agent and anti-aging agent, stir at 2000 rpm for 30 min, add diphenylmethane diisocyanate, stir at 3000 rpm for 10 s, quickly pour into a mold (size is 200mm×200mm×100mm), and place at room temperature for 48 h to obtain bioactive slow-release polyurethane memory foam.

[0026] Example 6: Preparation of Bioactive Sustained-Release Polyurethane Memory Foam (1) Weigh the following by weight: 85g polyether polyol, 5g hydroxyapatite, 0.4g catalyst (dibutyltin dilaurate), 0.8g dispersant (modified silicone oil), 8g deionized water, 1.8g foam stabilizer (DC-193 foam stabilizer), 1.5g antibacterial agent (prepared in Example 4), 0.8g antiaging agent (prepared in Example 2), and 50g diphenylmethane diisocyanate; (2) Mix polyether polyol, hydroxyapatite, catalyst, dispersant, deionized water, foam stabilizer, antibacterial agent and anti-aging agent, stir at 2000 rpm for 30 min, add diphenylmethane diisocyanate, stir at 3000 rpm for 10 s, quickly pour into a mold (size is 200mm×200mm×100mm), and place at room temperature for 48 h to obtain bioactive slow-release polyurethane memory foam.

[0027] Example 7 Preparation of Bioactive Sustained-Release Polyurethane Memory Foam (1) Weigh the following by weight: 90g polyether polyol, 6g hydroxyapatite, 0.5g catalyst (dibutyltin dilaurate), 1g dispersant (modified silicone oil), 10g deionized water, 2g foam stabilizer (DC-193 foam stabilizer), 2g antibacterial agent (prepared in Example 4), 1g antiaging agent (prepared in Example 3), and 55g diphenylmethane diisocyanate; (2) Mix polyether polyol, hydroxyapatite, catalyst, dispersant, deionized water, foam stabilizer, antibacterial agent and anti-aging agent, stir at 2000 rpm for 30 min, add diphenylmethane diisocyanate, stir at 3000 rpm for 10 s, quickly pour into a mold (size is 200mm×200mm×100mm), and place at room temperature for 48 h to obtain bioactive slow-release polyurethane memory foam.

[0028] Comparative Example 1 The raw material composition and preparation method of the bioactive sustained-release polyurethane memory foam are basically the same as those in Example 6, except that the anti-aging agent is replaced with an equal weight of an anti-aging agent prepared by the following method: The preparation method of the anti-aging agent is basically the same as that in Example 2, except that the 2-mercaptomethylbenzimidazole in step S1 is replaced with an equimolar amount of 2-mercapto-5-methylbenzimidazole.

[0029] Comparative Example 2 The raw material composition and preparation method of the bioactive sustained-release polyurethane memory foam are basically the same as those in Example 6, except that the anti-aging agent is replaced with an equal weight of an anti-aging agent prepared by the following method: The preparation method of the anti-aging agent is basically the same as that in Example 2, except that 2-(2,5,8,11-tetraoxadodecyl)ethylene oxide in step S2 is replaced with an equimolar amount of dodecyl glycidyl ether.

[0030] Comparative Example 3 The raw material composition and preparation method of the bioactive sustained-release polyurethane memory foam are basically the same as those in Example 6, except that the anti-aging agent is replaced with an equal weight of an anti-aging agent prepared by the following method: The preparation method of the anti-aging agent is basically the same as that in Example 2, except that 4,4'-diaminodiphenylamine in step S2 is replaced with an equimolar amount of 4,4'-diaminodiphenylmethane.

[0031] Comparative Example 4 The raw material composition and preparation method of the bioactive sustained-release polyurethane memory foam are basically the same as those in Example 6, except that the anti-aging agent is replaced with an equal weight of an anti-aging agent prepared by the following method: Under nitrogen protection, 750 ml of anhydrous tetrahydrofuran, 0.204 mol of benzimidazole-2-acetic acid, 0.21 mol of dicyclohexylcarbodiimide, and 0.04 mol of 4-dimethylaminopyridine were mixed and stirred for 15 min. Then, 0.1 mol of intermediate 2 (prepared in step S2 of Example 2) was added, and the mixture was reacted at 25 °C for 18 h. After filtration, the mixture was concentrated under reduced pressure at 40 °C for 2 h. The crude product was purified by silica gel column chromatography (V... 石油醚 :V 乙酸乙酯 The anti-aging agent was obtained by distillation at 40℃ under reduced pressure for 1 hour (ratio = 1:1).

[0032] Comparative Example 5 The raw material composition and preparation method of the bioactive sustained-release polyurethane memory foam are basically the same as those in Example 6, except that the antibacterial agent is replaced with an equal weight of an antibacterial agent prepared by the following method: The preparation method of the antibacterial agent is basically the same as that in Example 4, except that 9-octadecene-1-amine in step N1 is replaced with an equimolar amount of 9-decene-1-amine.

[0033] Comparative Example 6 The raw material composition and preparation method of the bioactive sustained-release polyurethane memory foam are basically the same as those in Example 6, except that the antibacterial agent is replaced with an equal weight of an antibacterial agent prepared by the following method: The preparation method of the antibacterial agent is basically the same as that in Example 4, except that the 4,5-dihydroxyphthalic acid in step N1 is replaced with an equimolar amount of 4-hydroxyphthalic acid.

[0034] Comparative Example 7 The raw material composition and preparation method of the bioactive sustained-release polyurethane memory foam are basically the same as those in Example 6, except that the antibacterial agent is replaced with an equal weight of an antibacterial agent prepared by the following method: The preparation method of the antibacterial agent is basically the same as that in Example 4, except that 4-[5-(methylsulfonyl)-1,3,4-oxadiazol-2-yl]benzoic acid in step N4 is replaced with an equimolar amount of 4-(5-methyl-1,3,4-oxadiazol-2-yl)benzoic acid.

[0035] Comparative Example 8 The raw material composition and preparation method of the bioactive sustained-release polyurethane memory foam are basically the same as those in Example 6, except that the antibacterial agent is replaced with an equal weight of an antibacterial agent prepared by the following method: The preparation method of the antibacterial agent is basically the same as that in Example 4, except that 4-[5-(methylsulfonyl)-1,3,4-oxadiazol-2-yl]benzoic acid in step N4 is replaced with an equimolar amount of 6-methylsulfonylnicotinic acid.

[0036] The polyether polyol used in the embodiments and comparative examples of this application is of the type WANOL. ® F3056D is produced by Wanhua Chemical Group Co., Ltd.; the hydroxyapatite model is HAP01-60, produced by Nanjing Junzhuo Biotechnology Co., Ltd.; the modified silicone oil model is DIS-8208, produced by Hangzhou Chongyao Technology Development Co., Ltd.; the CAS number of 4-[5-(methylsulfonyl)-1,3,4-oxadiazol-2-yl]benzoic acid is 2857963-64-3; the CAS number of 4,5-dihydroxyphthalic acid is 63958-66-7.

[0037] The bioactive sustained-release polyurethane memory foams prepared in Examples 5-7 and Comparative Examples 1-8 were tested, and the test results are shown in Table 1.

[0038] Tensile strength test: The polyurethane memory foam prepared in Examples 5-7 and Comparative Examples 1-8 were subjected to tensile strength test according to GB / T 6344-2008 standard. The memory foam was cut into type 1A specimens and the tensile speed was 500 mm / min.

[0039] Anti-aging performance test: The samples were placed in a QUV accelerated aging test chamber for aging tests, with an ultraviolet wavelength of 340nm and an irradiance of 0.76W / m. 2 The sample was aged at 60℃ for 600 hours, and then the tensile strength of the aged sample was tested again.

[0040] Antibacterial performance test: Staphylococcus aureus was selected as the test strain. Individual colonies were picked from the test strain and diluted with physiological saline to a bacterial concentration of 10.8 CFU / ml.

[0041] Add 100 μl of bacterial suspension to sterile LB liquid medium, then add polyurethane memory foam (cut into 10 mm × 10 mm × 1 mm pieces) prepared in Examples 5-7 and Comparative Examples 1-8 respectively, place on a constant temperature shaker, shake at 250 r / min for 1 h at 37 °C, then dilute with 9 ml PBS buffer (0.1 M, pH=7.4), and quantitatively inoculate the diluted bacterial suspension into culture dishes containing sterile agar medium (AGAR), incubate at 37 °C for 48 h, and count the bacteria; the control group is polyurethane memory foam prepared without antibacterial agent (the raw material composition and preparation method of polyurethane memory foam are basically the same as in Example 6, the difference being that no antibacterial agent is added to the components).

[0042] According to the formula (W: Antibacterial rate; A: Colony count of the control group after 48 hours; B: Colony count of the polyurethane memory foam prepared in Examples 5-7 and Comparative Examples 1-8 after 48 hours) The antibacterial rate was calculated.

[0043] Far-infrared performance test: The polyurethane memory foam prepared in Examples 5-7 and Comparative Examples 1-8 was cut into sheet-like samples with a diameter of 65 mm and a thickness of 10 mm. The far-infrared emissivity of the samples was tested in accordance with GB / T 30127-2013 standard at a temperature of 20℃ and a relative humidity of 65%.

[0044] Rebound performance test: The polyurethane memory foam prepared in Examples 5-7 and Comparative Examples 1-8 was cut into specimens with a size of 100mm×100mm×50mm, and the rebound rate of the specimens was tested according to Method B in GB / T 6670-2008.

[0045] Table 1 Performance Test Data As can be seen from Table 1, the polyurethane memory foam prepared in Examples 5-7 of this application has excellent tensile properties, anti-aging properties, antibacterial properties, far-infrared emission properties and slow rebound properties.

[0046] The anti-aging agents added to the components of the polyurethane memory foam prepared in Examples 5-7 of this application contain multifunctional structural units including hindered amines, benzimidazoles, thioesters, and flexible ether chains. These units can form a synergistic and long-lasting anti-aging and mechanical reinforcement system in the polyurethane memory foam. During the aging process, the hindered amine structure in the anti-aging agent first plays a "free radical capture-regeneration cycle" role, efficiently scavenging alkyl free radicals and peroxide free radicals generated during thermo-oxidative aging and photo-oxidative aging, and inhibiting the chain degradation reaction of the polyurethane main chain. Subsequently, the thioester structure acts as a peroxide decomposition unit, decomposing the hydroperoxides generated in the system into stable products, blocking the secondary generation channel of free radicals, and forming a synergistic antioxidant network with the hindered amine, significantly delaying the embrittlement of the cell walls and the breakage of molecular chains. The benzimidazole structure forms a rigid aromatic heterocyclic stable framework, which can absorb ultraviolet energy and improve the overall thermal stability of the molecule. At the same time, benzimidazole, through flexible ether chains, can also form a stable antioxidant network. The methyl bridge (-CH2-) connects to the thioester structure. The -CH2- bridging structure acts as a flexible spacer and electronic buffer between the thioester and benzimidazole: on the one hand, the -CH2- flexible segment improves the conformational tunability and compatibility and dispersibility of the anti-aging agent molecule in the polyurethane matrix; on the other hand, the -CH2- buffers the electronic effects of the benzimidazole ring, preventing strong conjugation from weakening the thioester structure, thus maintaining the thioester structure's ability to decompose hydroperoxides. The flexible ether chain endows the molecule with good compatibility and molecular chain entanglement, which can alleviate stress concentration and improve the tensile properties of polyurethane memory foam. The synergistic effect of the various structural units in the anti-aging agent molecule significantly enhances the tensile and anti-aging properties of polyurethane memory foam.

[0047] The thioester structure in the anti-aging agent used in Comparative Example 1 is directly linked to benzimidazole and lacks a -CH2- bridging structure. This prevents it from buffering the electronic effects of the benzimidazole ring, resulting in a weakened synergistic stabilizing ability between the thioester structure and the benzimidazole structure. Consequently, the anti-aging performance of the prepared polyurethane memory foam decreases.

[0048] The antibacterial agents added to the components of the polyurethane memory foam prepared in Examples 5-7 of this application simultaneously contain imidazolium cations, long-chain alkyl groups, benzoxazole sulfones, catechol, and secondary amine structures, forming a synergistic antibacterial system: First, the secondary amine structure reacts with polyurethane isocyanate during the foaming process, covalently anchoring the antibacterial agent to the polyurethane molecular chain, preventing migration or loss; simultaneously, the imidazolium cations in the antibacterial agent rapidly accumulate on the bacterial membrane surface through electrostatic adsorption, while the hydrophobic tails of the long-chain alkyl groups in the antibacterial agent molecules insert into the hydrophobic region of the cell membrane. Disrupting membrane structure and damaging cell membranes, it forms a synergistic unit of "cation adsorption-long-chain alkyl membrane disruption" with imidazolium cations, further enhancing bactericidal efficiency. Furthermore, the benzoxazole sulfone structure in the antibacterial agent molecule acts as a rigid aromatic heterocyclic skeleton, improving the thermal stability of the antibacterial agent and ensuring its non-decomposition and inactivation during polyurethane foaming and high-temperature use. Simultaneously, it prolongs the antibacterial effect by inhibiting bacterial metabolic systems. Subsequently, the catechol structure exerts its antioxidant and metal ion complexing effects, capturing oxygen free radicals and blocking bacterial extracellular polysaccharide synthesis, preventing biofilm formation. The synergistic effect of multiple structures in the antibacterial agent molecule significantly enhances the antibacterial properties of polyurethane memory foam.

[0049] The alkyl chain in the antibacterial agent used in Comparative Example 5 was shorter than that in the Example, which weakened its ability to disrupt bacterial cell membranes, resulting in a decrease in the antibacterial properties of the prepared polyurethane memory foam.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. However, any modifications, alterations, and variations made by those skilled in the art without departing from the scope of the present invention based on the disclosed technical content are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and variations made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the present invention.

Claims

1. A bioactive, sustained-release polyurethane memory foam, characterized in that, The ingredients include the following parts by weight: 80-90 parts of polyether polyol, 4-6 parts of hydroxyapatite, 0.3-0.5 parts of catalyst, 0.5-1 part of dispersant, 6-10 parts of deionized water, 1.5-2 parts of foam stabilizer, 1-2 parts of antibacterial agent, 0.5-1 part of anti-aging agent, and 45-55 parts of diphenylmethane diisocyanate; The anti-aging agent is prepared by the following method: S1: 2-Mercaptomethylbenzimidazole reacts with methyl acrylate to generate intermediate 1. S2: 2-(2,5,8,11-tetraoxadodecyl)ethylene oxide reacts with 4,4'-diaminodiphenylamine to form intermediate 2. S3: Intermediate 1 reacts with intermediate 2 to generate an anti-aging agent.

2. The bioactive sustained-release polyurethane memory foam according to claim 1, characterized in that, In step S1, the molar ratio of 2-mercaptomethylbenzimidazole to methyl acrylate is 1:(1.02-1.04).

3. The bioactive sustained-release polyurethane memory foam according to claim 1, characterized in that, In step S2, the molar ratio of 2-(2,5,8,11-tetraoxadodecyl)ethylene oxide to 4,4'-diaminodiphenylamine is (2.01-2.03):

1.

4. The bioactive sustained-release polyurethane memory foam according to claim 1, characterized in that, In step S3, the molar ratio of intermediate 1 to intermediate 2 is (2.03-2.05):

1.

5. The bioactive sustained-release polyurethane memory foam according to claim 1, characterized in that, The antibacterial agent is prepared by the following method: N1: 9-Octadecan-1-amine reacts with 4,5-dihydroxyphthalic acid to generate acetylated intermediate A; N2: Acetylation intermediate A is converted into acetylation intermediate B under the action of m-chloroperoxybenzoic acid; N3: Acetylation intermediate B reacts with 1-methyl-3-(3-aminopropyl)-3-chloroimidazolium to generate acetylation intermediate C; N4: The acetylated intermediate C reacts with 4-[5-(methylsulfonyl)-1,3,4-oxadiazol-2-yl]benzoic acid to generate an antibacterial agent.

6. The bioactive sustained-release polyurethane memory foam according to claim 5, characterized in that, In step N1, the molar ratio of 9-octadecene-1-amine to 4,5-dihydroxyphthalic acid is 2.05:1; in step N2, the molar ratio of acetylation intermediate A to m-chloroperoxybenzoic acid is 1:2.2; in step N3, the molar ratio of acetylation intermediate B to 1-methyl-3-(3-aminopropyl)-3-chloroimidazolium is 1:2.01; in step N4, the molar ratio of acetylation intermediate C to 4-[5-(methylsulfonyl)-1,3,4-oxadiazol-2-yl]benzoic acid is 1:2.

1.

7. The bioactive sustained-release polyurethane memory foam according to claim 1, characterized in that, The catalyst is dibutyltin dilaurate.

8. The bioactive sustained-release polyurethane memory foam according to claim 1, characterized in that, The dispersant is modified silicone oil.

9. The bioactive sustained-release polyurethane memory foam according to claim 1, wherein the foam stabilizer is DC-193 foam stabilizer.

10. A method for preparing a bioactive sustained-release polyurethane memory foam according to any one of claims 1-9, characterized in that, Includes the following steps: (1) Weigh out the following by weight: 80-90 parts of polyether polyol, 4-6 parts of hydroxyapatite, 0.3-0.5 parts of catalyst, 0.5-1 parts of dispersant, 6-10 parts of deionized water, 1.5-2 parts of foam stabilizer, 1-2 parts of antibacterial agent, 0.5-1 parts of anti-aging agent, and 45-55 parts of diphenylmethane diisocyanate; (2) Mix polyether polyol, hydroxyapatite, catalyst, dispersant, deionized water, foam stabilizer, antibacterial agent and anti-aging agent, add diphenylmethane diisocyanate, stir, quickly pour into mold, and cure at room temperature to obtain bioactive slow-release polyurethane memory foam.

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