Zr-mof-based functional flame retardant and preparation method and application thereof

Abstract

Zr-MOF-based functional flame retardant as well as a preparation method and application thereof, zirconium oxychloride, amino-containing dicarboxylic acid, organic acid and water are mixed, the molar ratio of zirconium oxychloride to the amino-containing dicarboxylic acid is 1:1, the mass ratio of the organic acid to water is x:(100-x), wherein 1<=x<=40, stirring reaction is carried out at 50-100 DEG C for 0.5-12 h, then polyformaldehyde and phosphorus-containing flame retardant are added, wherein the molar ratio of the amino-containing dicarboxylic acid, the polyformaldehyde and the phosphorus-containing flame retardant is 1:(1-2):(1-2), the molar ratio of the polyformaldehyde to the phosphorus-containing flame retardant is 1:1, then 70-100 DEG C continues to react for 4-8 h, after the reaction is finished, filtration, water washing and drying are carried out, and the Zr-MOF-based functional flame retardant is obtained.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of flame retardants, and particularly relates to a MOF functional flame retardant, a preparation method thereof and application of the MOF functional flame retardant in flame-retardant polyurethane foam. BACKGROUND

[0002] With the rapid development of polymer material science and processing technology, its application boundary continues to expand, and it has penetrated into many key fields such as building structure, transportation, electronics and electrical appliances, and home life, providing strong impetus for innovation and progress in various industries. However, it cannot be ignored that the inherent flammability of most polymer materials leads to frequent fire accidents, which poses a serious challenge to people's life and property safety and public safety. Under this background, it is urgent to modify the polymer materials to be flame-retardant, aiming to effectively reduce the risk of fire, slow down the spread of fire, and gain valuable time for fire rescue operations to maximize personnel safety.

[0003] Metal-organic framework (MOF) material, as a new type of porous material formed by the ingenious combination of metal ions and organic ligands, has shown unique charm due to its ultra-high specific surface area, structural diversity and tunability, uniform pore distribution, and atomic-level structural uniformity. It is particularly worth mentioning that the metal sites in MOF and their degradation products exhibit excellent catalytic oxidation and catalytic charring ability, and only a small amount of addition can significantly improve the flame-retardant efficiency of polymer materials such as polyurethane foam.

[0004] The highly ordered porous structure of MOF not only provides a physical restriction for the loading material, effectively avoiding the aggregation of the loading material, promoting its uniform dispersion inside the pore or on the framework surface, thereby enhancing the overall dispersion uniformity. In addition, the excellent chemical stability and thermal stability of MOF can significantly improve the thermal resistance of the foam after being integrated into the polyurethane foam, so that the foam can maintain structural stability and is not easy to decompose even under high temperature conditions. More importantly, the amino and hydroxyl functional groups on the surface of MOF can form chemical bonds with the polyurethane foam matrix, which not only enhances the fixation of the flame retardant and reduces the migration loss, but also effectively reduces the risk of secondary pollution to the environment, achieving the dual goals of flame retardation and environmental protection. SUMMARY

[0005] The application provides a zirconium-based metal-organic framework functional flame retardant with both flame retardation and mechanical property enhancement, a preparation method thereof and application of the zirconium-based metal-organic framework functional flame retardant in polyurethane foam. The thermal stability and dispersibility of the polyurethane foam are improved by adding the zirconium-based metal-organic framework flame retardant, so as to improve the flame retardation and mechanical properties of the prepared composite material.

[0006] Technical solution: A preparation method of Zr-MOF-based functional flame retardant, comprising the following steps: mixing zirconium oxychloride, amino-containing dicarboxylic acid, organic acid and water, the molar ratio of zirconium oxychloride and amino-containing dicarboxylic acid is 1:1, the mass ratio of organic acid to water is x:(100-x), wherein 1≤x≤40, stirring at 50-100℃ for 0.5-12h, then adding polyformaldehyde and phosphorus-containing flame retardant, wherein the molar ratio of amino-containing dicarboxylic acid, polyformaldehyde and phosphorus-containing flame retardant is 1:(1-2):(1-2), the molar ratio of polyformaldehyde and phosphorus-containing flame retardant is 1:1, then continuing to react at 70-100℃ for 4-8h, after the reaction is completed, filtering, washing with water and drying to obtain Zr-MOF-based functional flame retardant.

[0007] Preferably, the amino-containing dicarboxylic acid is 2-amino terephthalic acid, 2,5-diamino terephthalic acid or aspartic acid.

[0008] Preferably, the organic acid is formic acid or glacial acetic acid.

[0009] Preferably, the phosphorus-containing flame retardant is dimethyl phosphite, diethyl phosphite, diphenyl phosphite or DOPO.

[0010] The Zr-MOF-based functional flame retardant has the following structure:

[0011]

[0012] Wherein, R is any one of the following groups:

[0013]

[0014] The application of the Zr-MOF-based functional flame retardant in preparing flame-retardant polyurethane foam material.

[0015] The flame-retardant polyurethane foam material is prepared from the following components by weight parts: Zr-MOF-based functional flame retardant 5-20 parts, polyol 80-95 parts, isocyanate 50-120 parts, surfactant and catalyst accounting for 0.5%-1% of the mass of polyol respectively, and foaming agent accounting for 0.1%-2% of the mass of polyol; first, the polyol and Zr-MOF-based functional flame retardant are mixed and stirred, then other raw materials are added, and finally isocyanate is added for reaction to obtain the flame-retardant polyurethane foam material.

[0016] Preferably, the polyol is at least one of polyether polyol 4110, phthalic anhydride polyester polyol, polyester polyol 330N, rosin polyol and castor oil polyol.

[0017] Preferably, the surfactant is DC-193 or AK-1588.

[0018] Preferably, the catalyst is N,N-dimethylcyclohexylamine or butyldi tin dilaurate; the foaming agent is water or cyclopentane.

[0019] Beneficial effects: The zirconium-based metal organic framework (Zr-MOF) functional flame retardant provided by the application has the functions of flame retardation and mechanical property enhancement, and its preparation method and application in polyurethane foam are provided. By introducing the Zr-MOF flame retardant, the thermal stability of the polyurethane foam is significantly improved, the thermal decomposition process is effectively delayed, and the fire risk is reduced. At the same time, its unique structure and composition form a heat shield barrier in the polyurethane foam, preventing flame spread and smoke generation, and significantly improving the flame retardant grade of the material. In addition, the Zr-MOF flame retardant as a reinforcing phase is uniformly dispersed in the polyurethane foam, not only improving the flame retardant performance, but also enhancing the mechanical strength and toughness of the material, realizing the dual improvement of flame retardation and mechanical properties. Its good dispersity and compatibility avoid the agglomeration phenomenon of traditional flame retardants, ensuring the uniformity of the overall performance of the composite material. Moreover, the preparation method of the application focuses on environmental protection, uses green solvents and mild conditions, meets the requirements of sustainable development, and provides a new way for the development of more environmentally friendly and efficient flame retardants. In summary, the application not only significantly improves the comprehensive performance of the composite material, but also has environmental protection and sustainability, and has wide application prospect and social and economic value. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The microstructure of the Zr-MOF-based functional flame retardant.

[0021] Figure 2 The infrared spectrum of UiO-66-NH2@DOPO in Example 1.

[0022] Figure 3 The XRD spectrum of UiO-66-NH2@DOPO in Example 1. DETAILED DESCRIPTION

[0023] The application will be further described below in combination with specific embodiments.

[0024] Example 1

[0025] Zirconium oxychloride (0.01 mol), 2-amino terephthalic acid (0.01 mol), glacial acetic acid (10 g), water (90 g) were added into a flask, and the reaction was stirred at 80 °C for 4 h, then polyformaldehyde (0.02 mol) and DOPO (0.02 mol) were added, and the reaction was stirred at 80 °C for 4 h. After the reaction was completed, filtration, water washing and drying were performed to obtain UiO-66-NH2@DOPO. The obtained flame retardant (10 g) and castor oil polyol (100 g) were stirred at a rotation speed of 1500 r / min for 2 min, then 1% of butyldin laurate and DC-193 were added, 0.5% of water was added and stirring was continued for 20 s, then 85 g of PM-200 was added, and after curing for 8 h, a flame-retardant polyurethane composite foam was obtained. While fixing the remaining conditions, the mass of the flame retardant was changed to 5 g, 15 g and 20 g, respectively, to obtain a series of flame-retardant polyurethane composite foams (MPUF-X, X is the amount of flame retardant added).

[0026] Example 2

[0027] Zirconium oxychloride (0.05 mol), 2-amino terephthalic acid (0.05 mol), glacial acetic acid (20 g), water (80 g) were added into a flask, and the reaction was stirred at 100 °C for 2 h, then polyformaldehyde (0.05 mol) and diethyl phosphite (0.05 mol) were added, and the reaction was stirred at 80 °C for 4 h. After the reaction was completed, filtration, water washing and drying were performed to obtain UiO-66-NH2@diethyl phosphite. The obtained flame retardant (10 g) and phthalic anhydride polyol (100 g) were stirred at a rotation speed of 1500 r / min for 2 min, then 1% of butyldin laurate and DC-193 were added, 0.5% of water was added and stirring was continued for 20 s, then 85 g of PM-200 was added, and after curing for 8 h, a flame-retardant polyurethane composite foam was obtained. While fixing the remaining conditions, the mass of the flame retardant was changed to 5 g, 15 g and 20 g, respectively, to obtain a series of flame-retardant polyurethane composite foams (MPUF-X, X is the amount of flame retardant added).

[0028] Example 3

[0029] Zirconium oxychloride (0.02 mol), 2-amino terephthalic acid (0.02 mol), glacial acetic acid (30 g), water (70 g) were added into a flask, and the reaction was stirred at 80 °C for 8 h, then polyformaldehyde (0.04 mol) and DOPO (0.04 mol) were added, and the reaction was stirred at 80 °C for 6 h. After the reaction was completed, the product was filtered, washed with water and dried to obtain UiO-66-NH2@dimethyl phosphite. The obtained flame retardant (10 g) and polyether polyol 4110 (100 g) were stirred at a speed of 1500 r / min for 2 min, then 1% butyldi tin dilaurate and DC-193 were added, 0.5% water was added and stirred for 20 s, then 85 g of PM-200 was added, and the flame retardant polyurethane composite foam was obtained after curing for 8 h. The remaining conditions were fixed, and the mass of the flame retardant was changed to 5 g, 15 g and 20 g, respectively, to obtain a series of flame retardant polyurethane composite foams (MPUF-X, X is the amount of flame retardant added).

[0030] Example 4

[0031] Zirconium oxychloride (0.01 mol), aspartic acid (Asp, 0.01 mol), glacial acetic acid (30 g), water (70 g) were added into a flask, and the reaction was stirred at 70 °C for 10 h, then 38% formaldehyde aqueous solution (0.02 mol) and DOPO (0.02 mol) were added, and the reaction was stirred at 90 °C for 4 h. After the reaction was completed, the product was filtered, washed with water and dried to obtain Zr-Asp-MOF@DOPO. The obtained flame retardant (10 g) and castor oil polyol (100 g) were stirred at a speed of 1500 r / min for 2 min, then 1% butyldi tin dilaurate and DC-193 were added, 0.5% water was added and stirred for 20 s, then 85 g of PM-200 was added, and the flame retardant polyurethane composite foam was obtained after curing for 8 h. The remaining conditions were fixed, and the mass of the flame retardant was changed to 5 g, 15 g and 20 g, respectively, to obtain a series of flame retardant polyurethane composite foams (MPUF-X, X is the amount of flame retardant added).

[0032] Example 5

[0033] ​Zirconium oxychloride (0.04 mol), aspartic acid (Asp, 0.04 mol), glacial acetic acid (20 g), water (80 g) were added into a flask, and the reaction was stirred at 80 °C for 10 h, then 38% formaldehyde aqueous solution (0.08 mol) and diphenyl phosphite (0.08 mol) were added, and the reaction was stirred at 80 °C for 6 h. After the reaction was completed, the product was filtered, washed with water and dried to obtain Zr-Asp-MOF@ diphenyl phosphite. The obtained flame retardant (10 g) and phthalic anhydride polyol (100 g) were stirred at a speed of 1500 r / min for 2 min, then 1% butyldi tin dilaurate and DC-193 were added, 0.5% water was added and stirred for 20 s, then 90 g of PM-200 was added, and the flame retardant polyurethane composite foam was obtained after curing for 8 h. The remaining conditions were fixed, and the mass of the flame retardant was changed to 5 g, 15 g and 20 g, respectively, to obtain a series of flame retardant polyurethane composite foams (MPUF-X, X is the amount of flame retardant added).

[0034] Example 6

[0035] Zirconium oxychloride (0.02 mol), aspartic acid (Asp, 0.02 mol), formic acid (5 g), water (90 g) were added into a flask, and the reaction was stirred at 60 °C for 12 h, then 38% formaldehyde aqueous solution (0.04 mol) and diphenyl phosphite (0.04 mol) were added, and the reaction was stirred at 80 °C for 4 h. After the reaction was completed, the product was filtered, washed with water and dried to obtain Zr-Asp-MOF@ dimethyl phosphite. The obtained flame retardant (10 g) and polyether polyol 4110 (100 g) were stirred at a speed of 1500 r / min for 2 min, then 1% butyldi tin dilaurate and DC-193 were added, 0.5% water was added and stirred for 20 s, then 95 g of PM-200 was added, and the flame retardant polyurethane composite foam was obtained after curing for 8 h. The remaining conditions were fixed, and the mass of the flame retardant was changed to 5 g, 15 g and 20 g, respectively, to obtain a series of flame retardant polyurethane composite foams (MPUF-X, X is the amount of flame retardant added).

[0036] Comparative Example 1

[0037] Castor oil polyol (100 g), 1% butyldi tin dilaurate and DC-193 were stirred at a speed of 1500 r / min for 2 min, 0.5% water was added and stirred for 20 s, then 85 g of PM-200 was added, and the polyurethane foam was obtained after curing for 8 h.

[0038] Comparative Example 2

[0039] Phthalic anhydride polyol (100 g), 1% of dibutyltin dilaurate and DC-193 were stirred at 1500 r / min for 2 min, 0.5% of water was added and stirred for 20 s, then 90 g of PM-200 was added, and polyurethane foam was obtained after curing for 8 h.

[0040] Comparative Example 3

[0041] Polyether polyol 4110 (100 g), 1% of dibutyltin dilaurate and DC-193 were stirred at 1500 r / min for 2 min, 0.5% of water was added and stirred for 20 s, then 95 g of PM-200 was added, and polyurethane foam was obtained after curing for 8 h.

[0042] By comparing Examples 1-6 and Comparative Examples 1-3, the polyurethane foams without the addition of the UiO-66-NH2-based flame retardant failed to pass the UL-94 test, while the polyurethane composite foams with the addition of the UiO-66-NH2-based flame retardant all passed the UL-94 V-1 or V-0 level. In addition, the mechanical properties of the polyurethane composite foams with the addition of the UiO-66-NH2-based flame retardant were significantly enhanced.

[0043] The mechanical properties and flame retardant properties of the obtained flame-retardant polyurethane foams of the examples and comparative examples were tested, and the results are shown in Table 1.

[0044] Table 1

[0045] Shore hardness / A LOI / % Comparative 1 / MPUF 15 17.4 Comparative 2 / MPUF 70 18.4 Comparative 3 / MPUF 80 17.9 Example 1 / MPUF-5 45 23.4 Example 1 / MPUF-10 65 24.5 Example 1 / MPUF-15 75 27.1 Example 1 / MPUF-20 85 29.4 Example 2 / MPUF-5 72 23.9 Example 2 / MPUF-10 78 25.2 Example 2 / MPUF-15 85 27.7 Example 2 / MPUF-20 92 29.1

Claims

1. A method for preparing a Zr-MOF-based functional flame retardant, characterized in that, The process includes the following steps: Zirconium oxychloride, aminodicarboxylic acid, organic acid, and water are mixed, with a molar ratio of zirconium oxychloride to aminodicarboxylic acid of 1:1 and a mass ratio of organic acid to water of x:(100-x), where 1≤x≤40. The mixture is stirred at 50-100℃ for 0.5-12 hours. Then, paraformaldehyde and a phosphorus-containing flame retardant are added, with a molar ratio of aminodicarboxylic acid, paraformaldehyde, and phosphorus-containing flame retardant of 1:(1-2):(1-2) and a molar ratio of paraformaldehyde to phosphorus-containing flame retardant of 1:

1. The mixture is then stirred at 70-100℃ for 4-8 hours. After the reaction is complete, the mixture is filtered, washed with water, and dried to obtain a Zr-MOF-based functional flame retardant.

2. The preparation method of the Zr-MOF-based functional flame retardant according to claim 1, characterized in that, The aminodicarboxylic acid it contains is 2-aminoterephthalic acid, 2,5-diaminoterephthalic acid, or aspartic acid.

3. The preparation method of the Zr-MOF-based functional flame retardant according to claim 1, characterized in that, The organic acid is formic acid or glacial acetic acid.

4. The preparation method of the Zr-MOF-based functional flame retardant according to claim 1, characterized in that, The phosphorus-containing flame retardant is dimethyl phosphite, diethyl phosphite, diphenyl phosphite, or DOPO.

5. The Zr-MOF-based functional flame retardant prepared by any one of the preparation methods described in claims 1-4, characterized in that, The structure is as follows: Where R is any of the following groups:

6. The application of the Zr-MOF-based functional flame retardant as described in claim 5 in the preparation of flame-retardant polyurethane foam materials.

7. The application according to claim 6, characterized in that, By weight, flame-retardant polyurethane foam material is prepared from the following components: 5-20 parts of Zr-MOF-based functional flame retardant, 80-95 parts of polyol, 50-120 parts of isocyanate, surface activity and catalyst accounting for 0.5%-1% of the mass of polyol, and foaming agent accounting for 0.1%-2% of the mass of polyol. First, the polyol and Zr-MOF-based functional flame retardant are mixed and stirred, then other raw materials are added, and finally isocyanate is added to react and obtain flame-retardant polyurethane foam material.

8. The application according to claim 7, characterized in that, The polyol is at least one of polyether polyol 4110, phthalic anhydride polyester polyol, polyester polyol 330N, rosin polyol and castor oil polyol.

9. The application according to claim 7, characterized in that, The surfactant is either DC-193 or AK-1588.

10. The application according to claim 7, characterized in that, The catalyst is N,N-dimethylcyclohexylamine or dibutyltin dilaurate; the foaming agent is water or cyclopentane.

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