Zr-MOF-based functional flame retardant as well as preparation method and application thereof

Abstract

The invention relates to a Zr-MOF-based functional flame retardant and 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 amino-containing dicarboxylic acid is 1: 1, the mass ratio of organic acid to water is x: (100-x), 1 < = x < = 40, stirring reaction is carried out at 50-100 DEG C for 0.5-12 h, paraformaldehyde and a phosphorus-containing flame retardant are added, stirring reaction is carried out at 50-100 DEG C for 0.5-12 h, and the Zr-MOF-based functional flame retardant is obtained. Wherein the molar ratio of the amino-containing dicarboxylic acid to the paraformaldehyde to the phosphorus-containing flame retardant is 1: (1-2): (1-2), the molar ratio of the paraformaldehyde to the phosphorus-containing flame retardant is 1: 1, then continuously reacting for 4-8 hours at the temperature of 70-100 DEG C, and after the reaction is finished, filtering, washing and drying to obtain the Zr-MOF-based functional flame retardant.

Description

Technical Field

[0001] The present invention relates to the technical field of flame retardants, and specifically to a MOF functional flame retardant and a preparation method thereof, and application thereof in flame retardant polyurethane foam. Background Art

[0002] With the rapid development of polymer material science and processing technology, its application boundaries continue to expand, penetrating into many key areas such as building structure, transportation, electronics and electrical, home life, etc., providing a strong impetus for innovation and progress in all walks of life. However, it cannot be ignored that the inherent flammability of most polymer materials leads to frequent fire accidents, posing a severe challenge to the safety of people's lives and property and public safety. In this context, flame retardant modification of polymer materials has become a top priority, aiming to effectively reduce the risk of fire, slow the spread of fire, and win precious time for fire rescue operations to ensure maximum safety of personnel.

[0003] Metal-organic framework (MOF) materials, as a new type of porous material cleverly combined with metal ions and organic ligands, show unique charm with its ultra-high specific surface area, structural diversity and adjustability, uniform pore distribution and atomic-level structural uniformity. It is particularly worth mentioning that the metal sites in MOF and their degradation products show excellent catalytic oxidation and catalytic carbonization capabilities, and only a small amount of addition can significantly improve the flame retardant performance of polymer materials such as polyurethane foam.

[0004] The highly ordered porous structure of MOF not only provides physical confinement for the load, effectively avoids the aggregation of the load, and promotes its uniform dispersion inside the pores or on the surface of the frame, thereby enhancing the overall dispersion uniformity. In addition, the excellent chemical and thermal stability of MOF, after being incorporated into polyurethane foam, can significantly improve the thermal tolerance of the foam, allowing it to maintain structural stability even under high temperature conditions and not easily decompose. 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 migration and loss, but also effectively reduces the risk of secondary pollution to the environment, achieving the dual goals of flame retardancy and environmental protection. Summary of the invention

[0005] Technical problem to be solved: The present invention provides a zirconium-based metal organic framework functional flame retardant with both flame retardancy and enhanced mechanical properties, a preparation method thereof, and an application in polyurethane foam. By adding the zirconium-based metal organic framework flame retardant, the thermal stability and dispersibility of the polyurethane foam are improved, thereby improving the flame retardancy and mechanical properties of the prepared composite material.

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

[0007] Preferably, the amino-containing dicarboxylic acid is 2-aminoterephthalic acid, 2,5-diaminoterephthalic 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] Zr-MOF-based functional flame retardant, the structure is as follows:

[0011]

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

[0013]

[0014] Application of the above Zr-MOF-based functional flame retardant in the preparation of flame-retardant polyurethane foam material.

[0015] The flame retardant polyurethane foam material is prepared from the following ingredients by weight: 5-20 parts of Zr-MOF-based functional flame retardant, 80-95 parts of polyol, 50-120 parts of isocyanate, the surfactant and the catalyst account for 0.5%-1% of the mass of the polyol respectively, and the foaming agent accounts for 0.1%-2% of the mass of the polyol; firstly, the polyol and the Zr-MOF-based functional flame retardant are mixed and stirred, and then other raw materials are added, and finally isocyanate is added to react 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 above surfactant is DC-193 or AK-1588.

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

[0019] Beneficial effects: The zirconium-based metal organic framework (Zr-MOF) functional flame retardant provided by the present invention, which has both flame retardancy and mechanical property enhancement, and its preparation method and application in polyurethane foam, significantly improve the thermal stability of polyurethane foam by introducing Zr-MOF flame retardant, effectively delay the thermal decomposition process, and reduce the risk of fire; at the same time, its unique structure and composition form a heat insulation barrier in polyurethane foam, prevent the spread of flames and smoke generation, and significantly improve the flame retardant grade of the material; in addition, Zr-MOF flame retardant is uniformly dispersed in polyurethane foam as a reinforcing phase, which not only improves the flame retardancy, but also enhances the mechanical strength and toughness of the material, achieving a dual improvement in flame retardancy and mechanical properties; its good dispersibility and compatibility avoid the agglomeration phenomenon of traditional flame retardants, ensuring that the overall performance of the composite material is uniform and consistent; moreover, the preparation method of the present invention pays attention to environmental protection, adopts green solvents and mild conditions, meets the requirements of sustainable development, and provides a new way to develop more environmentally friendly and efficient flame retardants. In summary, the present invention not only significantly improves the comprehensive performance of composite materials, but also has both environmental protection and sustainability, and has broad application prospects and social and economic value. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

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

[0023] The present invention is further described below in conjunction with specific embodiments.

[0024] Example 1

[0025] Zirconium oxychloride (0.01 mol), 2-aminoterephthalic acid (0.01 mol), glacial acetic acid (10 g), and water (90 g) were added to a flask, heated to 80°C and stirred for 4 h, then paraformaldehyde (0.02 mol) and DOPO (0.02 mol) were added, and then stirred for 4 h at 80°C. After the reaction, the mixture was filtered, washed with water, and dried to obtain UiO-66-NH2@DOPO. The obtained flame retardant (10 g) and castor oil polyol (100 g) were stirred at 1500 r / min for 2 min, and then 1% of dibutyltin dilaurate and DC-193 were added, and 0.5% of water was added and stirred for 20 s, and then 85 g of PM-200 was added. After curing for 8 h, a flame retardant polyurethane composite foam was obtained. The other conditions were kept unchanged, 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 the flame retardant added).

[0026] Example 2

[0027] Zirconium oxychloride (0.05 mol), 2-aminoterephthalic acid (0.05 mol), glacial acetic acid (20 g), and water (80 g) were added to a flask, heated to 100 ° C and stirred for 2 h, then paraformaldehyde (0.05 mol) and diethyl phosphite (0.05 mol) were added, and then stirred for 4 h at 80 ° C. After the reaction, the mixture was filtered, washed with water, and dried to obtain UiO-66-NH2@diethyl phosphite. The obtained flame retardant (10 g) and phthalic anhydride polyol (100 g) were stirred at 1500 r / min for 2 min, and then 1% of dibutyltin dilaurate and DC-193 were added, and 0.5% of water was added and stirred for 20 s, and then 85 g of PM-200 was added. After curing for 8 h, a flame retardant polyurethane composite foam was obtained. The other conditions were kept unchanged, 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 the flame retardant added).

[0028] Example 3

[0029] Zirconium oxychloride (0.02 mol), 2-aminoterephthalic acid (0.02 mol), glacial acetic acid (30 g), and water (70 g) were added to a flask, heated to 80°C and stirred for 8 h, then added with paraformaldehyde (0.04 mol) and DOPO (0.04 mol), then stirred for 6 h at 80°C, filtered, washed with water, and dried after the reaction to obtain UiO-66-NH2@ dimethyl phosphite. The obtained flame retardant (10 g) and polyether polyol 4110 (100 g) were stirred at 1500 r / min for 2 min, then 1% of dibutyltin dilaurate and DC-193 were added, 0.5% of water was added and stirred 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. The other conditions were kept unchanged, 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 the flame retardant added).

[0030] Example 4

[0031] Zirconium oxychloride (0.01 mol), aspartic acid (Asp, 0.01 mol), glacial acetic acid (30 g), and water (70 g) were added to a flask, heated to 70 ° C and stirred for 10 h, then 38% formaldehyde aqueous solution (0.02 mol) and DOPO (0.02 mol) were added, and then stirred for 4 h at 90 ° C. After the reaction, the mixture 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 1500 r / min for 2 min, and then 1% of dibutyltin dilaurate and DC-193 were added, and 0.5% of water was added and stirred for 20 s, and then 85 g of PM-200 was added. After curing for 8 h, a flame-retardant polyurethane composite foam was obtained. The other conditions were kept unchanged, 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 the flame retardant added).

[0032] Example 5

[0033] Zirconium oxychloride (0.04 mol), aspartic acid (Asp, 0.04 mol), glacial acetic acid (20 g), and water (80 g) were added to a flask, heated to 80 ° C and stirred for 10 h, then 38% formaldehyde aqueous solution (0.08 mol) and diphenyl phosphite (0.08 mol) were added, and then stirred for 6 h at 80 ° C. After the reaction, the mixture 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 1500 r / min for 2 min, and then 1% of dibutyl tin dilaurate and DC-193 were added, and 0.5% of water was added and stirred for 20 s, and then 90 g of PM-200 was added. After curing for 8 h, a flame-retardant polyurethane composite foam was obtained. The other conditions were kept unchanged, 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 the flame retardant added).

[0034] Example 6

[0035] Zirconium oxychloride (0.02 mol), aspartic acid (Asp, 0.02 mol), formic acid (5 g), and water (90 g) were added to a flask, heated to 60 ° C and stirred for 12 h, then 38% formaldehyde aqueous solution (0.04 mol) and diphenyl phosphite (0.04 mol) were added, and then stirred for 4 h at 80 ° C. After the reaction, the mixture 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 1500 r / min for 2 min, and then 1% of dibutyltin dilaurate and DC-193 were added, 0.5% of water was added and stirred for 20 s, and then 95 g of PM-200 was added. After curing for 8 h, a flame retardant polyurethane composite foam was obtained. The other conditions were kept unchanged, 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 the flame retardant added).

[0036] Comparative Example 1

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

[0038] Comparative Example 2

[0039] Phthalic anhydride polyol (100 g), 1% dibutyltin dilaurate and DC-193 were stirred at 1500 r / min for 2 min, 0.5% water was added and stirring was continued for 20 s, 90 g 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% dibutyltin dilaurate and DC-193 were stirred at 1500 r / min for 2 min, 0.5% water was added and stirring was continued for 20 s, and then 95 g of PM-200 was added. After curing for 8 h, polyurethane foam was obtained.

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

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

[0044] Table 1

[0045] Shore hardness / A LOI / % Comparative Example 1 / MPUF 15 17.4 Comparative Example 2 / MPUF 70 18.4 Comparative Example 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 method comprises the following steps: mixing zirconium oxychloride, amino dicarboxylic acid, organic acid and water, wherein the molar ratio of zirconium oxychloride to amino dicarboxylic acid is 1:1, the mass ratio of organic acid to water is x:(100-x), wherein 1≤x≤40, stirring and reacting at 50-100°C for 0.5-12h, then adding polyformaldehyde and phosphorus-containing flame retardant, wherein the molar ratio of amino dicarboxylic acid, polyformaldehyde and phosphorus-containing flame retardant is 1:(1-2):(1-2), and the molar ratio of polyformaldehyde to phosphorus-containing flame retardant is 1:1, then continuing the reaction at 70-100°C for 4-8h, filtering after the reaction, washing with water and drying to obtain a Zr-MOF-based functional flame retardant.

2. The method for preparing the Zr-MOF-based functional flame retardant according to claim 1, characterized in that: The amino dicarboxylic acid is 2-aminoterephthalic acid, 2,5-diaminoterephthalic acid or aspartic acid.

3. The method for preparing 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 method for preparing 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 the preparation method according to any one of claims 1 to 4, characterized in that: The structure is as follows: Wherein, R is any one of the following groups:

6. Use of the Zr-MOF-based functional flame retardant according to claim 5 in the preparation of flame-retardant polyurethane foam materials.

7. The use according to claim 6, characterized in that: The flame retardant polyurethane foam material is prepared from the following ingredients by weight: 5-20 parts of Zr-MOF-based functional flame retardant, 80-95 parts of polyol, 50-120 parts of isocyanate, the surfactant and the catalyst account for 0.5%-1% of the mass of the polyol respectively, and the foaming agent accounts for 0.1%-2% of the mass of the polyol; firstly, the polyol and the Zr-MOF-based functional flame retardant are mixed and stirred, and then other raw materials are added, and finally isocyanate is added to react to obtain the flame retardant polyurethane foam material.

8. The use 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 use according to claim 7, characterized in that The surfactant is DC-193 or AK-1588.

10. The use 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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