Phosphorus-nitrogen rare earth compound and rare earth flame-retardant fabric

Abstract

The application provides a phosphorus-nitrogen rare earth compound and a rare earth flame-retardant fabric, which comprises a flame-retardant coating primer and a flame-retardant coating top glue, wherein the flame-retardant coating primer is made of raw materials including the following components in parts by weight: polyurethane emulsion 30-35 parts, the phosphorus-nitrogen rare earth compound of claim 1 15-50 parts, decabromodiphenyl ethane 5-25 parts, N,N-dimethylformamide 20-30 parts, a bridging agent 1-3 parts, a crosslinking agent 1-1.5 parts, and a promoter 0.2-1.5 parts. The phosphorus-nitrogen rare earth compound has excellent synergistic flame-retardant performance, can replace halogen and antimony-containing compounds in a flame-retardant system, reduces the generation of smoke and harmful gases, and has strong structural stability to the para-position structure of hydroxyphenyl phosphoric acid in the form of ion state under specific reaction conditions, and the specific triazine ring structure of melamine can effectively improve the thermal stability of the fabric.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of textiles, and particularly relates to a phosphorus-nitrogen rare earth compound and a rare earth flame-retardant fabric. BACKGROUND

[0002] Halogen flame retardants have many advantages such as excellent comprehensive performance and high cost performance, and are widely used in flame-retardant materials in the fields of building, transportation, electronic appliances and textiles. Halogen flame retardants are one of the most widely used organic flame retardants in the world. Due to the chemical properties of halogen elements, halogen flame retardants also have many disadvantages in use. Halogen flame retardants have poor thermal stability and will decompose to produce hydrogen halide gas and dense smoke under high temperature and open flame conditions, and smoke is the most direct factor leading to suffocation and casualties in a fire.

[0003] Phosphorus-nitrogen intumescent flame retardants are flame retardants mainly composed of phosphorus and nitrogen. Compared with common halogen flame retardants and antimony-containing flame retardants, the phosphorus-nitrogen intumescent flame retardants have the advantages of less smoke generation, less generation of toxic gases, and anti-dripping, and show good flame-retardant performance. Intumescent flame retardants are usually composed of three sources of acid source, carbon source and gas source. When the material burns, the acid source and the carbon source rapidly undergo esterification crosslinking reaction to form a molten carbon layer; the gas source releases nitrogen and water vapor and other inert non-combustible gases to make the molten carbon foam and expand, and at the same time dilutes the oxygen concentration around the burning object; the synergistic effect of the three sources forms a dense and porous expanded carbon layer on the surface of the material, which blocks heat and oxygen, thereby achieving the effect of flame retardation.

[0004] Rare earth is the general term of 17 chemical elements in group III B of the periodic table of chemical elements, and has unique 4f 0－14 5d 1 －10 6s 2 electronic layer structure, which makes it have the advantages of non-toxic, environmental protection, heat resistance, catalytic esterification and dehydrogenation reaction, and has a wide application in the chemical industry. The carbonization process of polymer burning itself is an esterification and dehydrogenation process, and a dense carbon layer can effectively prevent the spread of fire. SUMMARY

[0005] Therefore, the present application aims to overcome the defects in the prior art and provides a phosphorus-nitrogen rare earth compound and a rare earth flame-retardant fabric.

[0006] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0007] A phosphorus-nitrogen rare earth compound, the structural formula of the compound is shown as formula (I):

[0008]

[0009] In the formula, Re is a rare earth ion.

[0010] Further, the rare earth ions are at least one of lanthanum ions, cerium ions or yttrium ions.

[0011] The preparation method of the phosphorus-nitrogen rare earth compound comprises the following steps:

[0012] (1) adding p-carboxyphenyl phosphonic acid into deionized water, stirring and dispersing under heating until the solution is clear and colorless to obtain a p-carboxyphenyl phosphonic acid solution;

[0013] (2) adding rare earth nitrate into deionized water, stirring and dispersing to obtain a rare earth nitrate solution;

[0014] (3) adding the rare earth nitrate solution into the p-carboxyphenyl phosphonic acid solution dropwise, and reacting under heating to obtain a reaction solution;

[0015] (4) adding melamine into the reaction solution, and reacting under heating; after the reaction is completed, the reaction product is washed, filtered, dried, crushed to obtain the phosphorus-nitrogen rare earth compound.

[0016] Further, the molar ratio of the p-carboxyphenyl phosphonic acid, the rare earth nitrate and the melamine is 3:1:3; the rare earth nitrate is at least one of lanthanum nitrate, cerium nitrate or yttrium nitrate.

[0017] Further, the temperature of the heating step in the step (1) is 85-95℃; the temperature of the heating step in the step (3) is 90-95℃, and the reaction time is 3-6 hours; the temperature of the heating step in the step (4) is 95-100℃, and the reaction time is 5-8 hours.

[0018] A rare earth flame-retardant fabric, which comprises a flame-retardant coating primer and a flame-retardant coating topcoat, wherein the flame-retardant coating primer is made of raw materials comprising the following weight parts: polyurethane emulsion 30-35 parts, the phosphorus-nitrogen rare earth compound 15-50 parts, decabromodiphenyl ethane 5-25 parts, N,N-dimethylformamide 20-30 parts, bridging agent 1-3 parts, crosslinking agent 1-1.5 parts, and accelerator 0.2-1.5 parts.

[0019] Further, the flame-retardant coating topcoat is made of raw materials comprising the following weight parts: matting powder 1-3 parts, polyurethane emulsion 60-64 parts, and N,N-dimethylformamide 30-38 parts.

[0020] The preparation method of the rare earth flame-retardant fabric comprises the following steps:

[0021] Step 1 is to mix phosphorus-nitrogen rare earth compound, N, N-dimethylformamide, polyurethane emulsion, decabromodiphenyl ethane, bridging agent, crosslinking agent and accelerator to obtain a flame-retardant coating primer, coat the flame-retardant coating primer on a sample cloth, and then perform drying and curing to obtain a flame-retardant coating primer coating;

[0022] Step 2 is to mix matting powder, polyurethane emulsion and N, N-dimethylformamide to obtain a flame-retardant coating topcoat, coat the flame-retardant coating topcoat on the flame-retardant coating primer coating, and then perform drying and curing to form a flame-retardant coating topcoat coating to obtain the rare earth flame-retardant fabric.

[0023] Further, the viscosity of the flame-retardant coating primer in step 1 is 18000-20000 cps; the viscosity of the flame-retardant coating topcoat in step 2 is 18000-20000 cps.

[0024] Further, the sum of the thicknesses of the flame-retardant coating primer coating and the flame-retardant coating topcoat coating is 0.1-0.2 mm.

[0025] Further, the bridging agent in step 1 is at least one of toluene diisocyanate, isophorone diisocyanate, diphenyl methane diisocyanate or dicyclohexyl methane diisocyanate; and the accelerator in step 1 is at least one of triethylenediamine, A-1 or A-33.

[0026] Compared with the prior art, the present application has the following advantages:

[0027] The phosphorus-nitrogen rare earth compound has excellent synergistic flame-retardant performance, can replace halogen and antimony-containing compounds in the flame-retardant system, reduces the generation of smoke and harmful gases, and has strong structural stability to the para-position structure of hydroxyphenyl phosphoric acid under specific reaction conditions; the unique triazine ring structure of melamine can effectively improve the thermal stability of the fabric, and the high nitrogen content, low toxicity and non-flammability of melamine itself can provide a gas-phase flame-retardant mechanism by generating non-flammable gases such as nitrogen and water vapor under heat, and can synergistically act with acid sources and carbon sources to form an intumescent carbon layer, thereby achieving the flame-retardant effect of heat insulation, oxygen insulation, smoke suppression and anti-dripping.

[0028] The unique 4f 0－14 5d 1－10 6s 2 electronic layer structure of rare earth elements makes them have the advantages of non-toxicity, environmental protection, heat resistance, catalytic esterification and dehydrogenation reaction, etc., and the polymer combustion process is actually an esterification and dehydrogenation reaction, which provides the effect of catalytic charring in the polymer combustion process, accelerates the generation of intumescent carbon layer, and can effectively reduce the afterflame time of the fabric, reduce the flame spread speed and diffusion range.

[0029] The phosphorus-nitrogen rare earth compounds described in this invention improve the thermal stability of phosphorus-nitrogen flame retardants, reduce the spread of flames, reduce molten droplets, and at the same time reduce the amount of halogen and antimony-containing compounds added to the flame retardants, thereby reducing the amount of harmful gases released during combustion.

[0030] The preparation method described in this invention does not require high-temperature and high-pressure reactions, has a high yield of reactants, and does not use organic solvents during the reaction process, thus meeting the requirements of green and environmentally friendly practices. Attached Figure Description

[0031] Figure 1 This is a SEM image of the phosphorus and nitrogen rare earth compounds described in Example 1 of the present invention;

[0032] Figure 2 Thermogravimetric curves (30-800℃) of the phosphorus and nitrogen rare earth compounds described in Example 1 of this invention;

[0033] Figure 3 This is the Fourier transform infrared spectrum of the phosphorus and nitrogen rare earth compounds described in Example 1 of the present invention. Detailed Implementation

[0034] Unless otherwise defined, the technical terms used in the following embodiments have the same meanings as commonly understood by those skilled in the art. Unless otherwise specified, the experimental reagents used in the following embodiments are conventional biochemical reagents; and the experimental methods described are conventional methods.

[0035] The present invention will be described in detail below with reference to the embodiments.

[0036] Example 1

[0037] A method for preparing a phosphorus-nitrogen rare earth compound includes the following steps:

[0038] (1) Add 1.5 mol of p-carboxyphenylphosphonic acid to 350 ml of deionized water and stir and disperse under heating until the solution is clear and colorless to obtain p-carboxyphenylphosphonic acid solution.

[0039] (2) Add 0.5 mol of cerium nitrate to 120 ml of deionized water and stir to disperse, to obtain a cerium nitrate solution;

[0040] (3) The cerium nitrate solution was added dropwise to the p-carboxyphenylphosphonic acid solution, and the reaction was carried out at 90°C for 4 hours to obtain the reaction solution;

[0041] (4) Melamine was added to the reaction solution and reacted at 95°C for 6 hours. After the reaction was completed, the reaction product was washed, filtered, dried and pulverized to obtain the phosphorus and nitrogen rare earth compound.

[0042] A method for preparing a rare earth flame-retardant fabric includes the following steps:

[0043] Step 1 involves thoroughly mixing 30 parts of phosphorus-nitrogen rare earth compound, 10 parts of decabromodiphenyl ethane, 25 parts of N,N-dimethylformamide, 30 parts of polyurethane emulsion, 2 parts of toluene diisocyanate, and 0.8 parts of A-33 to obtain a flame-retardant coating primer. The flame-retardant coating primer is then applied to a sample fabric using a coating rod with a diameter of 0.5 cm, followed by drying and curing to obtain a flame-retardant coating primer coating.

[0044] Step 2 involves mixing 2.4 parts of matting powder, 62 parts of polyurethane emulsion, and 36 parts of N,N-dimethylformamide to obtain a flame-retardant coating topcoat. The flame-retardant coating topcoat is then applied onto the flame-retardant coating base coat using a coating rod with a diameter of 0.5 cm. After drying and curing, the flame-retardant coating topcoat is formed, resulting in the rare earth flame-retardant fabric.

[0045] Comparative Example 1

[0046] A method for preparing a phosphorus-nitrogen compound includes the following steps:

[0047] (1) Add 1.5 mol of p-carboxyphenylphosphonic acid to 350 ml of deionized water and stir and disperse under heating until the solution is clear and colorless to obtain p-carboxyphenylphosphonic acid solution.

[0048] (2) Add 1.5 mol of melamine to the carboxyphenylphosphonic acid solution and react at 95°C for 6 hours. After the reaction is completed, wash, filter, dry and pulverize the reaction product to obtain the phosphorus nitrogen compound.

[0049] A method for preparing a flame-retardant fabric includes the following steps:

[0050] Step 1 involves thoroughly mixing 30 parts of phosphorus-nitrogen rare earth compound, 10 parts of decabromodiphenyl ethane, 25 parts of N,N-dimethylformamide, 30 parts of polyurethane emulsion, 2 parts of toluene diisocyanate, and 0.8 parts of A-33 to obtain a flame-retardant coating primer. The flame-retardant coating primer is then applied to a sample fabric using a coating rod with a diameter of 0.5 cm, followed by drying and curing to obtain a flame-retardant coating primer coating.

[0051] Step 2 involves mixing 2.4 parts of matting powder, 62 parts of polyurethane emulsion, and 36 parts of N,N-dimethylformamide to obtain a flame-retardant coating topcoat. The flame-retardant coating topcoat is then applied onto the flame-retardant coating base coat using a coating rod with a diameter of 0.5 cm. After drying and curing, the flame-retardant coating topcoat is formed, resulting in the flame-retardant fabric.

[0052] Comparative Example 2

[0053] A method for preparing a phosphorus-nitrogen rare earth compound includes the following steps:

[0054] (1) Add 1.5 mol of p-carboxyphenylphosphonic acid to 350 ml of deionized water and stir and disperse under heating until the solution is clear and colorless to obtain p-carboxyphenylphosphonic acid solution.

[0055] (2) Add 0.5 mol of cerium nitrate to 120 ml of deionized water and stir to disperse, to obtain a cerium nitrate solution;

[0056] (3) The cerium nitrate solution was added dropwise to the p-carboxyphenylphosphonic acid solution and reacted at 90°C for 4 hours. After the reaction was completed, the reaction product was washed, filtered, dried and pulverized to obtain the phosphorus nitrogen rare earth compound.

[0057] A method for preparing a rare earth flame-retardant fabric includes the following steps:

[0058] Step 1 involves thoroughly mixing 30 parts of phosphorus-nitrogen rare earth compound, 10 parts of decabromodiphenyl ethane, 25 parts of N,N-dimethylformamide, 30 parts of polyurethane emulsion, 2 parts of toluene diisocyanate, and 0.8 parts of A-33 to obtain a flame-retardant coating primer. The flame-retardant coating primer is then applied to a sample fabric using a coating rod with a diameter of 0.5 cm, followed by drying and curing to obtain a flame-retardant coating primer coating.

[0059] Step 2 involves mixing 2.4 parts of matting powder, 62 parts of polyurethane emulsion, and 36 parts of N,N-dimethylformamide to obtain a flame-retardant coating topcoat. The flame-retardant coating topcoat is then applied onto the flame-retardant coating base coat using a coating rod with a diameter of 0.5 cm. After drying and curing, the flame-retardant coating topcoat is formed, resulting in the rare earth flame-retardant fabric.

[0060] Comparative Example 3

[0061] A method for preparing a flame-retardant fabric includes the following steps:

[0062] Step 1 involves thoroughly mixing 30 parts of ammonium polyphosphate, 10 parts of decabromodiphenyl ethane, 25 parts of N,N-dimethylformamide, 30 parts of polyurethane emulsion, 2 parts of toluene diisocyanate, 1.2 parts of A-331, and 0.8 parts of accelerator to obtain a flame-retardant coating primer. The flame-retardant coating primer is then applied to a sample fabric using a coating rod with a diameter of 0.5 cm, followed by drying and curing to obtain a flame-retardant coating primer layer.

[0063] Step 2 involves mixing 2.4 parts of matting powder, 62 parts of polyurethane emulsion, and 36 parts of N,N-dimethylformamide to obtain a flame-retardant coating topcoat. The flame-retardant coating topcoat is then applied onto the flame-retardant coating base coat using a coating rod with a diameter of 0.5 cm. After drying and curing, the flame-retardant coating topcoat is formed, resulting in the flame-retardant fabric.

[0064] Comparative Example 4

[0065] A method for preparing a flame-retardant fabric includes the following steps:

[0066] Step 1 involves thoroughly mixing 10 parts of decabromodiphenyl ethane, 25 parts of N,N-dimethylformamide, 30 parts of polyurethane emulsion, 2 parts of toluene diisocyanate, and 0.8 parts of A-33 to obtain a flame-retardant coating primer. The flame-retardant coating primer is then applied to a sample fabric using a coating rod with a diameter of 0.5 cm, followed by drying and curing to obtain a flame-retardant coating primer layer.

[0067] Step 2 involves mixing 2.4 parts of matting powder, 62 parts of polyurethane emulsion, and 36 parts of N,N-dimethylformamide to obtain a flame-retardant coating topcoat. The flame-retardant coating topcoat is then applied onto the flame-retardant coating base coat using a coating rod with a diameter of 0.5 cm. After drying and curing, the flame-retardant coating topcoat is formed, resulting in the flame-retardant fabric.

[0068] The flame-retardant coated fabrics prepared in Example 1 and Comparative Examples 1-5 were subjected to performance tests: the flame-retardant properties of each flame-retardant coated fabric were tested using a limiting oxygen index meter and a vertical burning tester, as shown in Table 1.

[0069] Table 1 Performance Results

[0070]

[0071] As shown in Table 1, the results of Example 1 and the comparative examples show that the introduction of rare earth phosphorus and nitrogen compounds effectively improved the limiting oxygen index of the materials and significantly enhanced the flame retardant effect.

[0072] In Comparative Example 1, the lack of coordinated rare earth ions resulted in a lack of catalytic carbonization, leading to increased afterburning time, increased longitudinal and lateral damage length, and more pronounced flame spread.

[0073] Comparative Example 2, without the introduction of melamine, showed a significant decrease in limiting oxygen index, a marked increase in afterburning time, more pronounced damage, and poor thermal stability of the material.

[0074] Comparative Example 3 used common phosphorus and nitrogen compounds, which had poor charring effect and the molten droplets ignited the cotton pad.

[0075] Comparative Example 4, without the addition of rare earth phosphorus and nitrogen compounds, had the lowest limiting oxygen index, and its UL94 flammability rating dropped to V-2, indicating significant damage.

[0076] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A phosphorus-nitrogen rare earth compound, characterized in that: The structural formula of the compound is shown in formula (Ⅰ): ， Equation (I) Wherein, Re is either a cerium ion or a lanthanum ion.

2. The method for preparing phosphorus and nitrogen rare earth compounds according to claim 1, characterized in that: Includes the following steps: (1) Add p-carboxyphenylphosphonic acid to deionized water and stir and disperse under heating conditions until the solution is clear and colorless to obtain p-carboxyphenylphosphonic acid solution; (2) Add rare earth nitrates to deionized water and stir to disperse them to obtain a rare earth nitrate solution; (3) The rare earth nitrate solution is added dropwise to the p-carboxyphenylphosphonic acid solution and reacted under heating conditions to obtain a reaction solution; (4) Melamine is added to the reaction solution and reacted under heating conditions. After the reaction is completed, the reaction product is washed, filtered, dried and pulverized to obtain the phosphorus nitrogen rare earth compound.

3. The method for preparing phosphorus and nitrogen rare earth compounds according to claim 2, characterized in that: The molar ratio of the carboxyphenylphosphonic acid, rare earth nitrate, and melamine is 3:1:3; the rare earth nitrate is lanthanum nitrate or cerium nitrate.

4. The method for preparing phosphorus and nitrogen rare earth compounds according to claim 2, characterized in that: The heating temperature in step (1) is 85-95℃; the heating temperature in step (3) is 90-95℃, and the reaction time is 3-6 hours; the heating temperature in step (4) is 95-100℃, and the reaction time is 5-8 hours.

5. A rare earth flame-retardant fabric, characterized in that: The fabric comprises a flame-retardant coating base and a flame-retardant coating top. The flame-retardant coating base is made from the following raw materials in parts by weight: 30-35 parts of polyurethane emulsion, 15-50 parts of the phosphorus-nitrogen rare earth compound as described in claim 1, 5-25 parts of decabromodiphenyl ethane, 20-30 parts of N,N-dimethylformamide, 1-3 parts of crosslinking agent, 1-1.5 parts of crosslinking agent, and 0.2-1.5 parts of accelerator.

6. The rare earth flame-retardant fabric according to claim 5, characterized in that: The flame-retardant coating adhesive is made from the following raw materials in parts by weight: 1-3 parts matting powder, 60-64 parts polyurethane emulsion, and 30-38 parts N,N-dimethylformamide.

7. The method for preparing the rare earth flame-retardant fabric according to claim 5 or 6, characterized in that: Includes the following steps: Step 1 involves thoroughly mixing phosphorus-nitrogen rare earth compounds, N,N-dimethylformamide, polyurethane emulsion, decabromodiphenyl ethane, crosslinking agent, and accelerator to obtain a flame-retardant coating primer. The flame-retardant coating primer is then applied to a sample fabric and dried and cured to obtain a flame-retardant coating primer layer. Step 2 involves mixing matting powder, polyurethane emulsion, and N,N-dimethylformamide to obtain a flame-retardant coating topcoat. This flame-retardant coating topcoat is then applied onto the flame-retardant base coat, followed by drying and curing to form the flame-retardant coating topcoat layer, resulting in the rare earth flame-retardant fabric.

8. The method for preparing rare earth flame-retardant fabric according to claim 7, characterized in that: The viscosity of the flame-retardant coating primer in step 1 is 18,000-20,000 cps; the viscosity of the flame-retardant coating topcoat in step 2 is 18,000-20,000 cps.

9. The method for preparing rare earth flame-retardant fabric according to claim 7, characterized in that: The sum of the thicknesses of the flame-retardant base coating and the flame-retardant top coating is 0.1-0.2 mm.

10. The method for preparing rare earth flame-retardant fabric according to claim 7, characterized in that: The crosslinking agent in step 1 is at least one of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, or dicyclohexylmethane diisocyanate; the accelerator in step 1 is at least one of triethylenediamine, A-1, or A-33.

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