A polyurethane foam and a method for producing the same

Abstract

The application relates to the field of polyurethane materials, in particular to a polyurethane foaming material and a preparation method thereof. The polyurethane foaming material comprises A component and B component; the mass ratio of the A component and the B component is 1: (1-1.5); the A component comprises the following raw materials in parts by weight: 100 parts of polyether polyol, 4-8 parts of flame-retardant dihydric alcohol, 1-3 parts of a chain extender, 3-8 parts of a foaming agent, 3-7 parts of a catalyst, 1-5 parts of a surfactant and 5-10 parts of modified carbon nanotubes; and the B component is isocyanate. The polyurethane foaming material has excellent antibacterial, flame-retardant, mechanical and aging-resistant properties.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of polyurethane materials, in particular to a kind of polyurethane foaming material and preparation method thereof. BACKGROUND

[0002] Polyurethane foaming material is an important product in polyurethane chemical system, with low production cost, simple forming process, good plasticity, small density and excellent mechanical properties, and is widely used in medical health, food packaging, building insulation, automobile parts manufacturing and other fields.

[0003] However, polyurethane foaming material also has some obvious defects: its porous hydrophilic surface is easy to breed bacteria, not only will cause material yellowing affect appearance, but also may cause mechanical properties to decline and service life to shorten due to microbial degradation, and even harm the environment and human health; and its flame retardancy is poor, and it spreads rapidly and easily produces melt drops when burning, accelerates the spread of fire, and releases a large amount of toxic gases mainly carbon monoxide, causing serious pollution. At present, although the flame retardancy can be improved by adding flame retardant, the mechanical properties of the material are often sacrificed. In addition, the material is also easy to be affected by ultraviolet light and cause aging, resulting in mechanical property decline and surface embrittlement, which seriously restricts its application. Therefore, it is necessary to develop a polyurethane foaming material with antibacterial, flame-retardant and aging-resistant properties. SUMMARY

[0004] In order to overcome the shortcomings of the prior art, one of the purposes of the present application is to provide a polyurethane foaming material with excellent antibacterial, flame-retardant, mechanical and aging-resistant properties.

[0005] The second purpose of the present application is to provide a preparation method of the above-mentioned polyurethane foaming material, which is simple.

[0006] One of the purposes of the present application is achieved by the following technical scheme:

[0007] A polyurethane foaming material, comprising A component and B component; the mass ratio of the A component and the B component is 1: (1-1.5); the A component comprises the following raw materials in parts by weight: polyether polyol 100 parts, flame-retardant diol 4-8 parts, chain extender 1-3 parts, foaming agent 3-8 parts, catalyst 3-7 parts, surfactant 1-5 parts, modified carbon nanotube 5-10 parts; the B component is isocyanate;

[0008] The structure of the flame-retardant diol is as follows:

[0009] .

[0010] Further, the preparation process of the modified carbon nanotube is as follows:

[0011] (1) adding amino carbon nanotubes into chloroform, then adding 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde, and then performing a reflux reaction after being heated, and then purifying to obtain intermediate 1;

[0012] The structural formula of the intermediate 1 is as follows:

[0013]

[0014] (2) adding the intermediate 1 into N,N-dimethylacetamide, then adding isopropyl isocyanate and dibutyltin dilaurate to perform a reaction, and then purifying to obtain the modified carbon nanotubes;

[0015] The structural formula of the modified carbon nanotubes is as follows:

[0016] .

[0017] Further, in step (1), the mass ratio of the amino carbon nanotubes and 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde is 1:(2.7-6.8); and the reflux reaction is performed for 2-5 hours.

[0018] Further, in step (2), the mass ratio of the intermediate 1, isopropyl isocyanate and dibutyltin dilaurate is 1:(1-2.5):(0.0015-0.006); the reaction is performed at a temperature of 60-80°C for 3-5 hours.

[0019] Further, the preparation process of the flame-retardant diol is as follows:

[0020] (a) dissolving 1,3-bis(oxazolidinylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione in dioxane, then adding chloroplatinic acid under an inert gas atmosphere and heating, and then adding bis(trimethylsilyloxymethyl)silane to perform a reaction, and then purifying to obtain compound 1;

[0021] The structural formula of the compound 1 is as follows:

[0022]

[0023] (b) adding the compound 1 and 1-(3-aminopropyl)imidazole into tetrahydrofuran, and then performing a reflux reaction under an inert gas atmosphere, and then purifying to obtain the flame-retardant diol.

[0024] Further, the mass ratio of the 1,3-bis(oxetane methyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, chloroplatinic acid, bis-trimethylsiloxy methyl silane in step (a) is 1:(0.9-1.9):(0.0002-0.0006); the heating temperature is 80-85℃; the reaction temperature is 70-75℃, and the reaction time is 6-9h.

[0025] Further, the mass ratio of the compound 1, 1-(3-aminopropyl) imidazole in step (b) is 1:(0.4-0.6); and the reflux reaction time is 18-22h.

[0026] Further, the polyether polyol is selected from one of polypropylene ether glycol, polyethylene ether glycol, polytetrahydrofuran ether glycol; and the chain extender is selected from one of ethylene glycol, 1,4-butanediol and triethanolamine.

[0027] Further, the catalyst is selected from one of dibutyl tin dilaurate, stannous octoate and triethylenediamine; the isocyanate is selected from one of toluene diisocyanate, phorone diisocyanate and hexamethylene diisocyanate; the foaming agent is water; and the surfactant is silicone oil.

[0028] The second object of the present application is achieved by the following technical scheme:

[0029] The preparation method of the polyurethane foaming material comprises the following steps:

[0030] (1) according to the weight fraction, the raw materials of the A component are weighed and uniformly mixed to obtain the A component;

[0031] (2) according to the mass ratio, the B component is weighed and added to the A component and uniformly mixed, and then poured into a mold to foam, and the polyurethane foaming material is obtained after curing.

[0032] Compared with the prior art, the present application has the following advantages:

[0033] 1. The present application provides a polyurethane foaming material prepared from polyether polyol, flame-retardant diol, isocyanate, modified carbon nanotube and the like, which has excellent antibacterial, flame-retardant, mechanical and aging-resistant properties.

[0034] 2. The polyurethane foam material of the present application adds a flame-retardant diol, which can improve the flame retardance and antibacterial properties of the polyurethane foam material, and effectively avoid the negative impact of the addition of traditional flame retardants on the mechanical properties of the material. Specifically, the flame-retardant diol is successfully introduced with siloxane by the silicon-hydrogen addition reaction of the double bond on 1,3-bis(oxymethylene methyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione and bis(trimethylsiloxy methyl) silane, and further introduced with imidazole groups by the ring-opening reaction of the epoxy group on 1,3-bis(oxymethylene methyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione and 1-(3-aminopropyl) imidazole, while generating alcohol. The flame-retardant diol is finally prepared. The flame-retardant mechanism of the flame-retardant diol is mainly condensed phase flame retardation, and gas phase dilution combustion inhibition is auxiliary: when the triazine ring and imidazole structure decompose at high temperature, non-combustible gases (NH3, N2, CO2, etc.) are released, which dilutes the concentration of oxygen and combustible gases, and at the same time forms an intumescent carbon layer covering the surface of the material, which insulates heat and oxygen transmission; the siloxane group will migrate to the surface of the material at high temperature to form a silicate or silicon oxide protective layer. Importantly, there is a synergistic effect between the siloxane group and the nitrogen-containing structure: the silicon oxide layer can enhance the stability of the carbon layer, forming a more robust and dense, high-temperature-resistant "carbon-ceramic composite protective layer", preventing the carbon layer from cracking or falling off, thereby more persistently playing a flame-retardant effect. In addition, the imidazole group in the flame-retardant diol also endows the material with excellent antibacterial properties.

[0035] 3. The polyurethane foam material of the present application also adds modified carbon nanotubes, which can improve the aging resistance of the polyurethane foam material, and also has excellent mechanical properties. Specifically, the present application introduces o-diphenol structure on the modified carbon nanotubes by Schiff base reaction of 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde and aminated carbon nanotubes, which can efficiently capture free radicals to inhibit oxidative degradation, thereby providing excellent aging resistance to the material; further, the alcohol hydroxyl group grafted on the carbon nanotube reacts with isopropyl isocyanate to form an urethane bond, which can form hydrogen bond interaction with the urethane group in the polyurethane segment, thereby improving the dispersibility of the carbon nanotube in the polyurethane matrix, effectively reducing its agglomeration phenomenon, and at the same time strengthening the interfacial bonding strength between the carbon nanotube and the polyurethane matrix. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 The infrared spectrum of the modified carbon nanotubes prepared in Preparation Example 1 of the present application. DETAILED DESCRIPTION

[0037] The application will be further described below in conjunction with the drawings and specific embodiments. It should be noted that the embodiments described below or technical features between the embodiments can be combined to form new embodiments without conflict. The specific conditions in the embodiments are not specified, and the conventional conditions or manufacturer's recommended conditions are used. The reagents or instruments used are conventional products obtained from commercial channels unless otherwise specified.

[0038] (Preparation Example 1)

[0039] (Preparation Example 1)

[0040] The preparation example provides a modified carbon nanotube, and the preparation process is as follows:

[0041]

[0042] (1) The amount ratio of aminated carbon nanotubes, 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde, and chloroform is 1 g:4 g:90 mL. The aminated carbon nanotubes are ultrasonically dispersed in chloroform, and then 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde (CAS:91147-04-5) is added. After warming, the reaction is refluxed for 4 h. After the reaction is completed, centrifugation is performed, and the solid product is collected and sequentially washed with anhydrous ethanol and deionized water. Vacuum drying is performed to obtain the intermediate 1.

[0043] (2) The amount ratio of the intermediate 1, isopropyl isocyanate, dibutyltin dilaurate, and N,N-dimethylacetamide is 1 g:2 g:0.004 g:35 mL. The intermediate 1 is ultrasonically dispersed in N,N-dimethylacetamide, and then isopropyl isocyanate and dibutyltin dilaurate are added. The reaction is performed at 70°C for 4 h. After the reaction is completed, centrifugation is performed, and the solid product is collected and sequentially washed with anhydrous ethanol and deionized water. Vacuum drying is performed to obtain the modified carbon nanotube.

[0044] (Preparation Example 2)

[0045] The preparation example provides a modified carbon nanotube, and the preparation process is as follows:

[0046] (1) The amount ratio of aminated carbon nanotubes, 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde, and chloroform is 1 g:2.7 g:75 mL. The aminated carbon nanotubes are ultrasonically dispersed in chloroform, and then 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde is added. After warming, the reaction is refluxed for 2 h. After the reaction is completed, centrifugation is performed, and the solid product is collected and sequentially washed with anhydrous ethanol and deionized water. Vacuum drying is performed to obtain the intermediate 1.

[0047] (2) The amount ratio of intermediate 1, isopropyl isocyanate, dibutyl tin dilaurate, N,N-dimethylacetamide is 1 g: 2.5 g: 0.006 g: 38 mL, intermediate 1 is ultrasonically dispersed in N,N-dimethylacetamide, then isopropyl isocyanate and dibutyl tin dilaurate are added, and the reaction is carried out at 80°C for 3h, after the reaction is completed, centrifugation is carried out, the solid product is collected and sequentially washed with anhydrous ethanol and deionized water, and vacuum drying is carried out, to obtain the modified carbon nanotube.

[0048] Preparation Example 3

[0049] The preparation example provides a modified carbon nanotube, and the preparation process is as follows:

[0050] (1) The amount ratio of aminated carbon nanotube, 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde, chloroform is 1 g: 6.8 g: 100 mL, the aminated carbon nanotube is ultrasonically dispersed in chloroform, then 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde is added, and the reaction is carried out under reflux after heating for 5h, after the reaction is completed, centrifugation is carried out, the solid product is collected and sequentially washed with anhydrous ethanol and deionized water, and vacuum drying is carried out, to obtain the intermediate 1;

[0051] (2) The amount ratio of intermediate 1, isopropyl isocyanate, dibutyl tin dilaurate, N,N-dimethylacetamide is 1 g: 2.5 g: 0.006 g: 38 mL, intermediate 1 is ultrasonically dispersed in N,N-dimethylacetamide, then isopropyl isocyanate and dibutyl tin dilaurate are added, and the reaction is carried out at 80°C for 3h, after the reaction is completed, centrifugation is carried out, the solid product is collected and sequentially washed with anhydrous ethanol and deionized water, and vacuum drying is carried out, to obtain the modified carbon nanotube.

[0052] Preparation Example 4

[0053] The preparation example provides a flame-retardant diol, and the preparation process is as follows:

[0054]

[0055] (a) with 1,3-bis(oxazolidinylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, chloroplatinic acid, bis(trimethylsilyloxymethyl)silane, dioxane in a ratio of 1 g:0.0004 g:1 g:12 mL, 1,3-bis(oxazolidinylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione (CAS: 69731-45-9) was dissolved in dioxane, heated to 82°C, and then chloroplatinic acid was added under a nitrogen atmosphere, followed by slow dropwise addition of bis(trimethylsilyloxymethyl)silane (CAS: 1873-88-7), and then the reaction was carried out at 72°C for 8 h. After the reaction was completed, the reaction solution was extracted with ethyl acetate, and the organic phase was washed with deionized water and saturated brine, dried over anhydrous magnesium sulfate, and distilled under reduced pressure to obtain compound 1 (yield 81.7%). The nuclear magnetic resonance and mass spectrometry results of compound 1 are as follows:

[0056] 1 HNMR: (C 19 H 37 N3O7Si3, 400 MHz, DMSO-d6) δ: 0.14 (s, 3H), 0.21 (s, 18H), 0.59-0.63 (t, 2H), 1.49-1.53 (m, 2H), 2.33-2.37 (m, 2H), 2.58-2.62 (m, 2H), 3.13-3.17 (m, 4H), 3.38-3.42 (m, 2H), 3.66-3.70 (t, 2H). MS (ESI) m / z = 503.19 [M].

[0057] (b) with compound 1, 1-(3-aminopropyl)imidazole, tetrahydrofuran in a ratio of 1 g:0.5 g:35 mL, compound 1 and 1-(3-aminopropyl)imidazole (CAS: 5036-48-6) were added to tetrahydrofuran, and the reaction was carried out at reflux under a nitrogen atmosphere for 20 h. After the reaction was completed, the reaction solution was concentrated by rotary evaporation, purified by silica gel column chromatography, the eluate was collected and concentrated, and P2O5 was used for vacuum drying to obtain the flame-retardant diol (yield 72.6%). The nuclear magnetic resonance and mass spectrometry results of the flame-retardant diol are as follows:

[0058] 1 HNMR: (C 31 H 59N9O7Si3, 400 MHz, DMSO-d6) δ: 0.14 (s, 3H), 0.21 (s, 18H), 0.59-0.63 (t, 2H), 1.49-1.53 (m, 2H), 1.87-1.91 (m, 4H), 2.51-2.55 (t, 4H), 3.08-3.12 (m, 4H), 3.23-3.27 (m, 2H), 3.33-3.37 (m, 4H), 3.66-3.70 (t, 2H), 4.02-4.06 (t, 4H), 4.49 (s, 2H), 5.52 (s, 2H), 6.77-6.79 (d, 2H), 7.16-7.19 (d, 2H), 7.92 (s, 2H). MS (ESI) m / z = 753.38 [M].

[0059] Preparation Example 5

[0060] The present preparation example provides a flame-retardant diol, and the preparation process is as follows:

[0061] (a) The amount ratio of 1,3-bis(oxymethylene methyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, chloroplatinic acid, bis-trimethylsiloxy methylsilane, dioxane is 1 g:0.0002 g:0.9 g:10 mL. The 1,3-bis(oxymethylene methyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione is dissolved in dioxane, heated to 80°C, then chloroplatinic acid is added under a nitrogen atmosphere, and then bis-trimethylsiloxy methylsilane is slowly added dropwise. Then, the reaction is carried out at 70°C for 9 h. After the reaction is completed, the reaction solution is extracted with ethyl acetate, and the organic phase is washed with deionized water and saturated brine, dried over anhydrous magnesium sulfate, and distilled under reduced pressure to obtain compound 1 (yield 80.4%). The nuclear magnetic resonance and mass spectrum results of compound 1 are the same as those of preparation example 4;

[0062] (b) The amount ratio of compound 1, 1-(3-aminopropyl)imidazole, tetrahydrofuran is 1 g:0.4 g:30 mL. The compound 1 and 1-(3-aminopropyl)imidazole are added to tetrahydrofuran, and the reaction is carried out at reflux under a nitrogen atmosphere for 18 h. After the reaction is completed, the reaction solution is concentrated by rotary evaporation, purified by a silica gel column, the eluent is collected and concentrated, and dried with P2O5 under vacuum to obtain the flame-retardant diol (yield 71.9%). The nuclear magnetic resonance and mass spectrum results of the flame-retardant diol are the same as those of preparation example 4.

[0063] Preparation Example 6

[0064] The present preparation example provides a flame-retardant diol, and the preparation process is as follows:

[0065] (a) with 1,3-bis(oxazolidinylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, chloroplatinic acid, bis-trimethylsiloxy methylsilane, dioxane in a ratio of 1 g:0.0006 g:1.9 g:12.5 mL, the 1,3-bis(oxazolidinylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione is dissolved in dioxane, heated to 85°C, then chloroplatinic acid is added under a nitrogen atmosphere, and then bis-trimethylsiloxy methylsilane is slowly added dropwise, and then reacted at 75°C for 6 h, after the reaction is completed, the reaction solution is extracted with ethyl acetate, the organic phase is washed with deionized water and saturated brine, dried over anhydrous magnesium sulfate, and distilled under reduced pressure to obtain the compound 1 (yield 81.1%), and the nuclear magnetic resonance and mass spectrum results of the compound 1 are the same as those of Preparation Example 4;

[0066] (b) with the compound 1, 1-(3-aminopropyl)imidazole, tetrahydrofuran in a ratio of 1 g:0.6 g:40 mL, the compound 1 and 1-(3-aminopropyl)imidazole are added to tetrahydrofuran, heated to reflux under a nitrogen atmosphere for 22 h, after the reaction is completed, the reaction solution is concentrated by rotary evaporation, purified by a silica gel column, the eluent is collected and concentrated, and dried with P2O5 under vacuum to obtain the flame-retardant diol (yield 71.7%), and the nuclear magnetic resonance and mass spectrum results of the flame-retardant diol are the same as those of Preparation Example 4.

[0067] (II) Examples

[0068] Example 1

[0069] The present example provides a polyurethane foam material, which comprises A component and B component in a mass ratio of 1:1.2. Wherein the A component comprises the following raw materials in parts by weight: polypropylene ether diol 100 parts, flame-retardant diol prepared in Preparation Example 4 6 parts, ethylene glycol 2 parts, water 4 parts, dibutyltin dilaurate 5 parts, silicone oil 3 parts, modified carbon nanotube prepared in Preparation Example 1 6 parts; and the B component is toluene diisocyanate.

[0070] The present example provides a preparation method of the above-mentioned polyurethane foam material as follows:

[0071] (1) according to parts by weight, weigh each raw material of the A component, and stir at 2500 rpm for 30 s to obtain the A component;

[0072] (2) according to the mass ratio, weigh the B component and add it to the A component, stir at 2500 rpm for 4 s, then pour into a mold to foam, and obtain the polyurethane foam material after curing for 24 h.

[0073] Example 2

[0074] The embodiment provides a polyurethane foaming material, which comprises A component and B component, and the mass ratio of the A component to the B component is 1:1. The A component comprises the following raw materials in parts by weight: polyethylene oxide ether dihydric alcohol 100 parts, the flame-retardant dihydric alcohol prepared in the preparation example 5 4 parts, 1,4-butanediol 1 part, water 3 parts, stannous octoate 3 parts, silicon oil 1 part, and the modified carbon nanotube prepared in the preparation example 2 5 parts; and the B component is a phorone diisocyanate.

[0075] The embodiment provides a preparation method of the polyurethane foaming material.

[0076] (1) the raw materials of the A component are weighed according to parts by weight, 2500 rpm stirring is conducted for 30 s, and the A component is obtained;

[0077] (2) the B component is weighed according to the mass ratio and added into the A component, 2500 rpm stirring is conducted for 4 s, then the polyurethane foaming material is obtained by pouring into a mold and foaming, and aging for 24 h.

[0078] Example 3

[0079] The embodiment provides a polyurethane foaming material, which comprises A component and B component, and the mass ratio of the A component to the B component is 1:1.5. The A component comprises the following raw materials in parts by weight: polytetrahydrofuran ether dihydric alcohol 100 parts, the flame-retardant dihydric alcohol prepared in the preparation example 6 8 parts, triethanolamine 3 parts, water 8 parts, triethylenediamine 7 parts, silicon oil 5 parts, and the modified carbon nanotube prepared in the preparation example 3 10 parts; and the B component is a hexamethylene diisocyanate.

[0080] The embodiment provides a preparation method of the polyurethane foaming material.

[0081] (1) the raw materials of the A component are weighed according to parts by weight, 2500 rpm stirring is conducted for 30 s, and the A component is obtained;

[0082] (2) the B component is weighed according to the mass ratio and added into the A component, 2500 rpm stirring is conducted for 4 s, then the polyurethane foaming material is obtained by pouring into a mold and foaming, and aging for 24 h.

[0083] (Three) Comparative Example

[0084] Comparative Example 1

[0085] The difference between the comparative example and the example 1 is that the flame-retardant dihydric alcohol prepared in the preparation example 4 is omitted.

[0086] Comparative Example 2

[0087] The difference between the comparative example and the example 1 is that the modified carbon nanotube is replaced by an aminated carbon nanotube.

[0088] (Four) Experimental Example

[0089] Experimental Example 1

[0090] The modified carbon nanotubes prepared in Preparation Example 1 were subjected to infrared spectrum (FT-IR) analysis, and the results are shown in Figure 1. Figure 1

[0091] Figure 1 Figure 1 is an infrared spectrum of the modified carbon nanotubes prepared in Preparation Example 1 of the present application, wherein curve a is an infrared spectrum of the aminated carbon nanotubes, and curve b is an infrared spectrum of the modified carbon nanotubes. It can be observed that, compared with the aminated carbon nanotubes, the modified carbon nanotubes have characteristic absorption peaks of C=O and benzene ring skeleton at 1720 cm -1 , 1575 cm -1 , which indicates that the modification of the carbon nanotubes is successful.

[0092] Experimental Example 2

[0093] The properties of the materials obtained in Examples 1-3 and Comparative Examples 1-2 were detected, and the details are as follows.

[0094] Tensile strength: detection was performed according to GB / T6344-2008, and the results are shown in Table 1.

[0095] Tear strength: detection was performed according to GB / T10808-2006, and the results are shown in Table 1.

[0096] Limiting oxygen index: detection was performed according to GB / T2406.2-2009, and the results are shown in Table 1.

[0097] Rebound resilience: detection was performed according to GB / T6670-2008, and the results are shown in Table 1.

[0098] Bacteriostatic rate: the antibacterial rates of Staphylococcus aureus and Escherichia coli were determined according to WS / T650-2019, and the results are shown in Table 1.

[0099] Yellowing resistance: the polyurethane foaming material was first subjected to aging treatment under the condition of 250W ultraviolet light for 60h, and then the discoloration was evaluated by using a gray sample card according to GB / T250-2008, and the yellowing resistance grade (1-5) was determined by the color change of the gray card (1 grade is the worst, and 5 grade is the best), and the results are shown in Table 1.

[0100] Table 1

[0101]

[0102] ​As can be seen from Table 1, compared with Comparative Example 1, the polyurethane foaming material obtained by adding the flame-retardant diol in Example 1 has excellent flame-retardant performance, mechanical properties and antibacterial properties. The above results show that the flame-retardant diol obtained by the present application can improve the flame-retardant performance and antibacterial properties of the polyurethane foaming material, and effectively avoid the negative impact of the addition of traditional flame retardants on the mechanical properties of the material. Further analysis shows that, by the silicon-hydrogen addition reaction between the double bond on 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione and bis(trimethylsilyloxy)methylsilane, siloxane is successfully introduced, and by the ring-opening reaction between the epoxy group on 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione and 1-(3-aminopropyl)imidazole, imidazole groups are introduced, and alcohol is generated at the same time, and finally the flame-retardant diol is obtained. The flame-retardant mechanism of the flame-retardant diol is mainly condensed phase flame retardation, and gas phase dilution is auxiliary: when the triazine ring and imidazole structure decompose at high temperature, non-combustible gases (NH3, N2, CO2, etc.) are released, which dilutes the concentration of oxygen and combustible gases, and at the same time, an intumescent carbon layer is formed on the surface of the material to isolate the transfer of heat and oxygen; the siloxane group migrates to the surface of the material at high temperature to form a silicate or silicon oxide protective layer. Importantly, there is a synergistic effect between the siloxane group and the nitrogen-containing structure: the silicon oxide layer can enhance the stability of the carbon layer, forming a more robust and dense, high-temperature-resistant "carbon-ceramic composite protective layer", preventing the carbon layer from cracking or falling off, thereby more persistently playing a flame-retardant effect. In addition, the imidazole groups in the flame-retardant diol also endow the material with excellent antibacterial properties.

[0103] Compared with Comparative Example 2, the polyurethane foaming material obtained by using the modified carbon nanotube in Example 1 has good aging resistance, and also has excellent mechanical properties. The above results show that the modified carbon nanotube obtained by the present application can improve the aging resistance and mechanical properties of the polyurethane foaming material. Further analysis shows that, by the Schiff base reaction between 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde and aminated carbon nanotubes, the o-diphenol structure is introduced on the modified carbon nanotube, which can efficiently capture free radicals, thereby inhibiting oxidative degradation and providing excellent anti-aging properties for the material; further, by the reaction between the alcohol hydroxyl group grafted on the carbon nanotube and isopropyl isocyanate, an urethane bond is generated, which can form hydrogen bond interaction with the urethane groups in the polyurethane segment, thereby improving the dispersibility of the carbon nanotube in the polyurethane matrix, effectively reducing the agglomeration phenomenon, and at the same time, strengthening the interfacial bonding strength between the carbon nanotube and the polyurethane matrix.

[0104] The above embodiments are only the preferred embodiments of the present application, and cannot be used to limit the protection scope of the present application, and any non-essential changes and replacements made by those skilled in the art on the basis of the present application shall fall within the protection scope of the present application.

Claims

1. A polyurethane foam material, characterized in that, It includes component A and component B; the mass ratio of component A to component B is 1:(1-1.5); by weight, component A includes the following raw materials: 100 parts of polyether polyol, 4-8 parts of flame retardant diol, 1-3 parts of chain extender, 3-8 parts of foaming agent, 3-7 parts of catalyst, 1-5 parts of surfactant, and 5-10 parts of modified carbon nanotubes; component B is isocyanate; The structural formula of the flame-retardant diol is as follows: ； The structural formula of the modified carbon nanotubes is as follows: 。 2. The polyurethane foam material according to claim 1, characterized in that, The preparation process of the modified carbon nanotubes is as follows: (1) Aminated carbon nanotubes were added to chloroform, and then 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde was added. The mixture was heated and refluxed. After the reaction was completed, it was purified to obtain intermediate 1. The structural formula of intermediate 1 is as follows: (2) The intermediate 1 was added to N,N-dimethylacetamide, and then isopropyl isocyanate and dibutyltin dilaurate were added to react. After the reaction was completed, the modified carbon nanotubes were obtained by purification.

3. The polyurethane foam material according to claim 2, characterized in that, The mass ratio of the aminated carbon nanotubes and 7,8-dihydroxy-6-(1-hydroxy-1-methylethyl)-4-methyl-1-naphthaldehyde in step (1) is 1:(2.7-6.8); the reflux reaction time is 2-5 h.

4. The polyurethane foam material according to claim 2, characterized in that, In step (2), the mass ratio of intermediate 1, isopropyl isocyanate, and dibutyltin dilaurate is 1:(1-2.5):(0.0015-0.006); the reaction temperature is 60-80℃ and the reaction time is 3-5h.

5. The polyurethane foam material according to claim 1, characterized in that, The preparation process of the flame-retardant diol is as follows: (a) 1,3-bis(epoxyethylenemethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione was dissolved in dioxane, chloroplatinic acid was added under an inert gas atmosphere and heating conditions, and then bistrimethylsiloxymethylsilane was added to carry out the reaction. After the reaction was completed, the mixture was purified to obtain compound 1. The structural formula of compound 1 is as follows: (b) The compound 1 and 1-(3-aminopropyl)imidazol were added to tetrahydrofuran and refluxed under an inert gas atmosphere. After the reaction was completed, the mixture was purified to obtain the flame-retardant diol.

6. The polyurethane foam material according to claim 5, characterized in that, In step (a), the mass ratio of 1,3-bis(epoxyethylenemethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, chloroplatinic acid, and bistrimethylsiloxymethylsilane is 1:(0.0002-0.0006):(0.9-1.9); the heating temperature is 80-85℃; the reaction temperature is 70-75℃, and the reaction time is 6-9h.

7. The polyurethane foam material according to claim 5, characterized in that, In step (b), the mass ratio of compound 1 to 1-(3-aminopropyl)imidazole is 1:(0.4-0.6); the reflux reaction time is 18-22 h.

8. The polyurethane foam material according to claim 1, characterized in that, The polyether polyol is selected from one of polypropylene oxide ether diol, polyethylene oxide ether diol, and polytetrahydrofuran ether diol; the chain extender is selected from one of ethylene glycol, 1,4-butanediol, and triethanolamine.

9. The polyurethane foam material according to claim 1, characterized in that, The catalyst is selected from one of dibutyltin dilaurate, stannous octoate, and triethylenediamine; the isocyanate is selected from one of toluene diisocyanate, phorone diisocyanate, and hexamethylene diisocyanate; the foaming agent is water; and the surfactant is silicone oil.

10. A method for preparing a polyurethane foam material according to any one of claims 1-9, characterized in that, Includes the following steps: (1) Weigh each raw material of component A according to the weight proportions and mix them evenly to obtain component A; (2) Weigh component B according to the mass ratio and add it to component A and mix evenly. Then pour it into a mold to foam and cure to obtain the polyurethane foam material.

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