MOF-containing hyperbranched flame retardant and its manufacturing method

Abstract

To provide a nitrogen-containing hyperbranched flame retardant containing MOF and a producing method thereof.SOLUTION: By using a specific MOF, a diamino compound, and triglycidyl cyanurate as a hyperbranched basic structure, the shortcomings of additive-type flame retardants such as poor compatibility with a matrix, low flame retardant efficiency, and loss during use are resolved, and in the case of flame-retardant polymers, a high flame retardant effect can be achieved by blending a small amount of MOF-containing hyperbranched flame retardant with a phosphorus-containing flame retardant through the intumescent flame retardant action and synergistic catalytic action. The MOF-containing hyperbranched flame retardant of the present invention has high flame retardant efficiency.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to the technical field of flame retardants, in particular to MOF-containing hyperbranched flame retardants, their preparation methods and uses. [Background technology]

[0002] Triglycidyl isocyanurate (TGIC) is a heterocyclic polyepoxy compound with excellent heat resistance, weather resistance, adhesive properties, and high-temperature properties. TGIC is primarily used as a curing agent for carboxyl-containing polyesters and carboxyl acrylic resin powder coatings. High-purity TGIC is commonly used in the manufacture of adhesives, electrical insulating laminates, plastic stabilizers, and other applications. Due to its high nitrogen content and characteristic epoxy groups, TGIC is widely used in the manufacture of nitrogen-containing compound precursors in intumescent flame retardants.

[0003] Metal-organic frameworks (MOFs) are ordered crystalline frameworks formed by the self-assembly of metal ions and organic ligands. Due to their large specific surface area, regular pore structure, and tunable surface chemistry, they have been widely applied in fields such as gas storage, catalysis, separation, and drug delivery. In recent years, MOF materials have been widely used as novel flame retardants for various polymers due to their high thermal stability. Because MOFs offer a wide variety of transition metals, flame-retardant elements, and potential carbon sources, and their structure and performance can be easily tuned, MOFs, their derivatives, and MOF hybrids are expected to be used in flame retardant research. Based on MOF modification strategies, MOFs (metal-organic frameworks) can be coupled with gas sources at the nanoscale. This review will be extremely useful for researchers to quickly grasp the latest developments in this field.

[0004] Hyperbranched polymers are highly branched polymers with a highly three-dimensional structure. Conventional hyperbranched polymer intumescent flame retardants have problems such as low nitrogen content, weak carbon generation ability, and low flame retardant efficiency. However, by introducing an MOF structure into these hyperbranched flame retardants, it is expected that the above problems of current flame retardants can be solved.

[0005] Chinese invention patent publication CN104262680B discloses a hyperbranched intumescent flame retardant and its manufacturing method, which involves reacting phthalic anhydride with diethanolamine, etc. to produce AB2 monomer, thereby improving the flame retardant efficiency of the flame retardant. However, since the components do not contain MOF, the optimization is insufficient. Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention provides MOF-containing hyperbranched flame retardants, methods for their preparation and use. [Means for solving the problem]

[0007] In order to solve the above technical problems, the present invention is achieved by the following technical solutions. A MOF-containing hyperbranched flame retardant having the structure shown in Formula I. [ka] (In Formula I, Y is —NH— or —N—; R is a piperazine ring, a branched alkylene group containing 1 to 30 carbon atoms, an aryl group, or a polycyclic aromatic hydrocarbon group; The meandering lines are extensions of the hyperbranched structures, and the circles are amino-containing MOF structures.)

[0008] A method for producing a MOF-containing hyperbranched flame retardant, comprising: The MOF-containing hyperbranched flame retardant is the MOF-containing hyperbranched flame retardant described above, and the production method includes: Step (1) of dissolving a diamine compound in a polar organic solvent in an inert gas environment, then adding a catalyst, and then heating to 70 to 150°C; Step (2) dissolving triglycidyl isocyanurate in a polar organic solvent, then slowly adding it to the mixture obtained in step (1), and carrying out a ring-opening reaction under inert gas protection, maintaining the ring-opening reaction temperature at 80°C to 150°C, and reacting for 8 to 24 hours with stirring to obtain a nitrogen-containing hyperbranched flame retardant; The nitrogen-containing hyperbranched flame retardant obtained in step (2) is added with an MOF material containing an amino group, and the mixture is stirred continuously for 8 to 24 hours to carry out a capping reaction. Then, a precipitant is added, followed by solid-liquid separation, washing with water, and drying to obtain a MOF-containing hyperbranched flame retardant having a structure represented by Formula I: get Step (3)

[0009] Preferably, the diamine compound is one or a mixture of more than one of piperazine, ethylenediamine, hydroxyethylethylenediamine, 3,3-diaminodiphenylsulfone, diethyltoluenediamine, 2,6-toluenediamine, N-aminoethylpiperazine, N,N-dimethyl-1,3-propylenediamine, diaminodiphenylmethane, or diaminodiphenylsulfone.

[0010] Preferably, the catalyst is N,N-dimethylcyclohexylamine, bis(2-dimethylaminoethyl)ether, N,N,N',N'-tetramethylalkylenediamine, N,N-dimethylbenzylamine, triethylamine, N-ethylmorpholine, N,N'-diethylpiperazine, N,N'-dimethylpyridine, or pyridine.

[0011] Preferably, the amino-containing MOF structure is an amino-containing metal-organic framework, such as one or more of NH2-UiO-66(Zr), NH2-UiO-66(Hf), NH2-MIL-53(Fe), NH2-MIL-101(Fe), NH2-MIL-53(Al), NH2-MIL-101(Al), NH2-MIL-101(Cr), or NH2-MIL-125(Ti), and the capping reaction is capping the hyperbranched flame retardant through an epoxy ring-opening reaction of the amino group.

[0012] Preferably, the polar organic solvent is acetonitrile, dichloroethane, chloroform, dimethylformamide, or dimethylsulfoxide.

[0013] Preferably, the molar ratio of the triglycidyl isocyanurate to the diamine compound is (2.5-10):(1-2), and the mass ratio of the triglycidyl isocyanurate + the diamine compound to the MOF material containing an amino group is (3-5):1.

[0014] Preferably, the inert gas is one or more of nitrogen gas, argon gas, or helium gas.

[0015] Preferably, the precipitant in step (3) is water; The reaction product obtained by the capping reaction is precipitated with water, followed by solid-liquid separation, washing with water, and drying to obtain a MOF-containing hyperbranched flame retardant having the structure shown in Formula I.

[0016] A method of using a MOF-containing hyperbranched flame retardant, specifically the use of the above-mentioned MOF-containing hyperbranched flame retardant in the field of flame retardancy.

[0017] In the present invention, when the diamine compound and MOF are in the form of a mixture, the ratio of each substance in the mixture is not particularly limited, except for the specific limitations of the present invention, and a mixture of any ratio can be used. In the present invention, except for the specific limitations, the origin of the diamine compound is not particularly limited, and commercially available products known to those skilled in the art can be used.

[0018] In the present invention, the principle of the ring-opening reaction is the following reaction equation: [ka]

[0019] In the above reaction equation, Y is -NH- or -N-, R is a piperazine ring or a branched alkylene group containing 1 to 30 carbon atoms, an aryl group, or a polycyclic aromatic hydrocarbon group, and ○ is an amino-containing MOF structure.

[0020] In the present invention, after the precipitation is completed, the system after the precipitation is subjected to solid-liquid separation to obtain a solid product. In the present invention, the specific method of solid-liquid separation is not particularly limited, and any solid-liquid separation method known to those skilled in the art, specifically, filtration, may be used.

[0021] In the present invention, after the solid product is obtained, the solid product is preferably washed with water to obtain a water-washed product. In the present invention, there are no particular limitations on the number of times of washing with water and the amount of water used.

[0022] In the present invention, after obtaining the aqueous product, the water-washed product is preferably dried to obtain the nitrogen-containing hyperbranched flame retardant. In the present invention, the specific drying method is not particularly limited, and any drying method known to those skilled in the art may be used. Specifically, the drying is preferably performed by vacuum drying at 50°C for 2 to 10 hours.

[0023] The present invention provides the use of the MOF-containing hyperbranched flame retardant according to the above technical solution or the MOF-containing hyperbranched flame retardant prepared by the preparation method according to any of the above technical solutions in the field of flame retardancy, more preferably in flame retardant resins.

[0024] In the present invention, the mass percentage of the MOF-containing hyperbranched flame retardant in the polymer material is preferably 5 to 15%. [Effects of the Invention]

[0025] The beneficial effects of the present invention are as follows: In the present invention, a nitrogen-containing hyperbranched flame retardant containing MOF is formed by adding a structure to an amino-containing MOF as a core through a specific configuration, and the flame retardant material formed with the flame retardant has a flame retardancy level that is substantially V0 level (at least V1 or higher), and a limiting oxygen index (LOI) of 32 or higher, and in a better embodiment, 37 or higher (the limiting oxygen index (LOI) of polyolefin materials is conventionally 21), thereby significantly improving the flame retardancy. The specific preparation method according to the present invention has mild reaction conditions, is easy to carry out the preparation process, and can impart good flame retardancy to polymeric materials. The hyperbranched flame retardant has a high nitrogen content, making it an excellent gas source and synergistic flame retardant for intumescent flame retardants, and provides efficient flame retardancy to materials such as epoxy resins and polyolefins. DETAILED DESCRIPTION OF THE INVENTION

[0026] The following provides a clear and complete description of the technical aspects of the embodiments of the present invention, but it is clear that the described embodiments are only some of the embodiments of the present invention and do not cover all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without performing any creative work fall within the scope of protection of the present invention.

[0027] The MOF-containing hyperbranched flame retardant according to the present invention, its preparation method and use will be described in detail below with reference to examples, which should not be construed as limiting the scope of protection of the present invention. [Example]

[0028] 0.52 mol of anhydrous piperazine was dissolved in 250 ml of acetonitrile and added to a 500 ml three-neck flask equipped with a reflux condenser, a constant pressure dropping funnel, and a stirrer. 0.01 mol of triethylamine was added and the system was heated to 85°C. Next, 0.25 mol of triglycidyl isocyanurate (TAIC) was dissolved in 100 ml of acetonitrile and added dropwise to the above system. Under nitrogen protection, the temperature was adjusted and maintained at 85°C and mechanically stirred for 8 hours. 25 g of NH2-MIL-101(Fe) was added and stirred for 8 hours. 200 ml of water was then added as a precipitant, stirring was stopped, the mixture was suction filtered while still hot, washed three times with water, and dried under vacuum at 90°C for 8 hours to obtain a MOF-containing hyperbranched flame retardant. Comparative Example 1

[0029] In this comparative example, except for the step of "adding NH2-MIL-101(Fe)", all the other steps were the same as in Example 1. A comparison of the obtained results is shown in Table 2. [Example]

[0030] A solution of 0.5 mol of ethylenediamine in 300 mL of dimethyl sulfoxide was added to a 500 mL three-neck flask equipped with a reflux condenser, a constant pressure dropping funnel, and a stirrer. 0.01 mol of triethylamine was added and the system was heated to 120°C. Next, 0.20 mol of triglycidyl isocyanurate (TAIC) was dissolved in 100 mL of dimethylformamide and added dropwise to the above system. Under nitrogen protection, the mixture was kept at 120°C and stirred for 10 hours. 15 g of NH2-MIL-125(Ti) was added and stirred for 10 hours. 100 mL of water was added as a precipitant, stirring was stopped, the mixture was suction filtered while still hot, washed six times with water, and dried in vacuo at 80°C for 8 hours to obtain a MOF-containing hyperbranched flame retardant. Comparative Example 2

[0031] In this comparative example, except for the step of "adding NH2-MIL-125(Ti)", all the other steps were the same as in Example 2. A comparison of the obtained results is shown in Table 2. [Example]

[0032] A solution of 0.5 mol of diaminodiphenylmethane in 300 mL of chloroform was added to a 500 mL three-necked flask equipped with a reflux condenser, a constant pressure dropping funnel, and a stirrer. 0.01 mol of N,N-dimethylcyclohexylamine was added and the system was heated to 70°C. Next, 0.25 mol of triglycidyl isocyanurate was dissolved in 100 mL of chloroform and added dropwise to the above system. The system was kept at 80°C under nitrogen protection and stirred for 8 hours. 15 g of NH2-MIL-125(Ti) was added and stirred for 10 hours. 150 mL of water was added as a precipitant. The stirring was stopped, the mixture was suction filtered while still hot, washed four times with water, and dried in vacuo at 80°C for 8 hours to obtain a MOF-containing hyperbranched flame retardant. Comparative Example 3

[0033] In this comparative example, except for the absence of the "NH2-MIL-125(Ti)" step, all other steps were the same as in Example 3. A comparison of the obtained results is shown in Table 2.

[0034] To examine the flame retardancy of the MOF-containing hyperbranched flame retardants of the present invention, a flammable epoxy resin was used as the matrix, and the flame retardants prepared in Examples 1, 2, and 3 were added to the epoxy resin in the ratios shown in Table 1. The mixture was mixed uniformly and poured into a mold. The mixture was then heat-cured to prepare a standard sample. The standard sample was subjected to a flame retardancy test in accordance with the UL94 test standard (SATM D3801-10) and the LOI test standard (ASRM D2863-06A). The test results are shown in Table 1.

[0035] [Table 1]

[0036] The typical manufacturing processes of Comparative Examples 1, 2, and 3 do not include a step of adding a MOF flame retardant, resulting in a conventional nitrogen-containing hyperbranched flame retardant that does not contain MOF. Similar to Table 1, the flame retardants manufactured in Comparative Examples 1, 2, and 3 were added to epoxy resin in the blending ratios shown in Table 2 (the corresponding blending methods correspond to Table 1). After uniform mixing, the mixture was poured into a mold and heat-cured to produce a standard sample. The standard sample was subjected to flame retardancy tests in accordance with the UL94 test standard (SATM D3801-10) and the LOI test standard (ASRM D2863-06A). The test results are shown in Table 2.

[0037] [Table 2]

[0038] As can be seen from Tables 1 and 2, the flame retardant prepared by the present invention can be produced under mild reaction conditions, with a simple and easy production process, and can impart good flame retardancy to polymeric materials. In each example, the MOF-containing hyperbranched flame retardant prepared by the present invention was mixed with APP in a 1:2 and 2:1 ratio, respectively, to form flame retardant materials for comparison. When added to the flame retardant materials in the same ratio, the LOI values were all higher than the LOI values in Table 2 when no MOF was added, demonstrating that the flame retardancy of the present invention can be improved by adding an appropriate MOF material to the flame retardant.

Claims

1. 1. A MOF-containing hyperbranched flame retardant, characterized in that it has a structure as shown in Formula I: 【Chemical 1】 (In Formula I, Y is —NH— or —N—; R is a piperazine ring or a branched alkylene group, an aryl group, or a polycyclic aromatic hydrocarbon group containing 1 to 30 carbon atoms; The meandering lines are extensions of the hyperbranched structures, and the circles are amino-containing MOF structures.

2. 1. A method for producing a MOF-containing hyperbranched flame retardant, comprising: The MOF-containing hyperbranched flame retardant is the MOF-containing hyperbranched flame retardant of claim 1, and the production method comprises: Step (1) of dissolving a diamine compound in a polar organic solvent in an inert gas environment, then adding a catalyst, and then heating to 70 to 150°C; Step (2) dissolving triglycidyl isocyanurate in a polar organic solvent, then slowly adding it to the mixture obtained in step (1), and carrying out a ring-opening reaction under inert gas protection, maintaining the ring-opening reaction temperature at 80°C to 150°C, and reacting for 8 to 24 hours with stirring to obtain a nitrogen-containing hyperbranched flame retardant; and (3) adding an amino group-containing MOF material to the nitrogen-containing hyperbranched flame retardant obtained in step (2), stirring continuously for 8 to 24 hours to carry out a capping reaction, and then adding a precipitant and carrying out solid-liquid separation, washing with water, and drying steps to obtain the MOF-containing hyperbranched flame retardant having a structure represented by formula I, which contains an MOF structure.

3. 3. The method according to claim 2, wherein the diamine compound is one or a mixture of a plurality of piperazine, ethylenediamine, hydroxyethylethylenediamine, 3,3-diaminodiphenylsulfone, diethyltoluenediamine, 2,6-toluenediamine, N-aminoethylpiperazine, N,N-dimethyl-1,3-propylenediamine, diaminodiphenylmethane, and diaminodiphenylsulfone.

4. 3. The method according to claim 2, wherein the catalyst is N,N-dimethylcyclohexylamine, bis(2-dimethylaminoethyl)ether, N,N,N',N'-tetramethylalkylenediamine, N,N-dimethylbenzylamine, triethylamine, N-ethylmorpholine, N,N'-diethylpiperazine, N,N'-dimethylpyridine, or pyridine.

5. The amino-containing MOF structure is an amino-containing metal organic framework material, and NH ２ -UiO-66(Zr), NH ２ -UiO-66 (Hf), NH ２ -MIL-53 (Fe), NH ２ -MIL-101(Fe), NH ２ -MIL-53 (Al), NH ２ -MIL-101 (Al), NH ２ -MIL-101(Cr) or NH ２ -MIL-125(Ti), and the capping reaction is capping the hyperbranched flame retardant through an epoxy ring-opening reaction of the amino group.

6. 3. The method according to claim 2, wherein the polar organic solvent is acetonitrile, dichloroethane, chloroform, dimethylformamide, or dimethyl sulfoxide.

7. The production method according to claim 2, characterized in that the molar ratio of triglycidyl isocyanurate to the diamine compound is (2.5-10):(1-2), and the mass ratio of triglycidyl isocyanurate + diamine compound to the MOF material containing amino groups is (3-5):

1.

8. 3. The manufacturing method according to claim 2, wherein the inert gas is one or more of nitrogen gas, argon gas, and helium gas.

9. The precipitant in step (3) is water; The method of claim 2, wherein the reaction product obtained by the capping reaction and water are precipitated, followed by solid-liquid separation, washing with water, and drying to obtain the MOF-containing hyperbranched flame retardant having the structure shown in Formula I.

10. A method for using the nitrogen-containing hyperbranched flame retardant according to claim 1 or the MOF-containing hyperbranched flame retardant produced by the production method according to any one of claims 2 to 9 in the field of flame retardancy.

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