Low-odor phosphazene catalyst and application thereof

Abstract

The invention discloses a low-odor phosphazene catalyst and application thereof. The low-odor phosphazene catalyst comprises phosphazene cations as shown in a general formula (I) and alkali metal salt compound anions, the catalyst takes phosphorus pentahalide and guanidine compounds as raw materials, the phosphorus pentahalide is dissolved in a non-benzene organic solution, an organic phosphonium salt solution containing an organic solvent and a halogenated phosphorus compound is obtained through a reaction under the heating condition, then an alkali metal salt compound is added, a reaction is conducted under the inert atmosphere and the heating condition, and the guanidine compounds are obtained. And carrying out filtration, reduced pressure distillation, purification and vacuum drying to obtain the purified phosphazene catalyst. The catalyst is applied to preparation of polyether polyol and polyurethane foam materials. When the phosphazene catalyst is prepared, a non-benzene inert solvent which does not participate in the reaction is adopted, the solvent does not need to be frequently replaced, and the steps of extraction, distillation and the like are reduced by using the same solvent, so that the energy consumption and the generation of wastewater and waste materials in the process are reduced. The continuous preparation method of the phosphazene catalyst is efficient and environment-friendly.

Description

Technical Field

[0001] The invention relates to a catalyst and application thereof, in particular to a low-odor phosphazene catalyst and application thereof. Background Art

[0002] Phosphazene catalysts have excellent ring-opening catalytic ability, high activity and stability in the reaction process, few side reaction products, and can prepare polyether polyols with higher molecular weight and higher activity, and have low unsaturation and few by-products. Some patents mention the preparation process used to prepare phosphazene catalysts, and their process technology is complicated, time-consuming and inefficient. For example, patent DE102006010034 and patent CN102171272B require multi-step reactions and multi-step treatments to obtain the catalyst. The process involves a variety of raw materials, solvents and water, and there are phenomena of serious time-consuming and energy-consuming, and wastewater and waste polluting the environment. In today's rapidly developing society, energy waste and environmental pollution force people to pay attention to energy saving and efficiency improvement when carrying out industrial production, and they need to pay attention to the protection of the living environment at all times.

[0003] In addition, the prior art mentions that the use of phosphazene catalyst process can prepare high molecular weight and low unsaturation polyether polyols, and the polyether polyols of the phosphazene catalytic system have a large odor, which makes the subsequent treatment more complicated. The odor mainly comes from two parts, one is the influence of the selection of phosphazene catalyst, and the other is the by-products produced during the reaction and some small molecules of alcohols, aldehydes, ketones and benzene impurities, and these impurities often affect the performance of the polyurethane material prepared by the polyether polyol. At present, the treatment methods of crude polyethers used by polyether manufacturers at home and abroad are mostly post-treatment methods of neutralization and adsorption. These are optimized from the process and raw materials, but the odor has not been improved much after all. With the continuous progress of society and people's continuous pursuit of a better and healthier life, the customer group has continuously increased the demand for the odor of polyether polyols and their products. These and other factors force researchers to not only optimize the odor of polyether polyols, but also optimize the catalyst end to reduce the odor of polyethers and reduce the harmful substances brought by polyethers.

[0004] The prior art discloses a catalyst for the manufacture of polyalkylene glycols, which uses phosphorus pentachloride and tetramethylguanidine to prepare a phosphazenium salt intermediate in a benzene solvent, and after purification, replaces the anion with a hydroxide, and then mixes with an active hydrogen compound, and heats the mixture to obtain a catalyst for the manufacture of polyalkylene glycols. The catalyst is further used to catalyze the polymerization of epoxy compounds such as propylene oxide, and is applied to the field of polyurethane foams. However, the catalyst produced by using toluene as a solvent in production has many problems such as a strong odor and excessive benzene. The prior art also discloses an organic alcohol salt phosphazene catalyst prepared by synthesizing an intermediate in a benzene solvent using phosphorus trichloride and tetramethylguanidine, and then ion-exchanging the intermediate. The catalyst of the invention can also be used in the ring-opening polymerization of epoxy compounds to prepare high molecular weight and low unsaturation polyether polyols.

[0005] In summary, the preparation of phosphazene catalysts in the prior art usually requires the use of several different organic solvents containing benzene series, and the organic solvents used need to be extracted and washed after the reaction, and the reaction product also needs to be obtained by ion exchange, which will generate a large amount of waste water and waste solvents in the entire preparation process. Therefore, the phosphazene catalysts in the prior art generally have many problems such as high toxicity and danger of raw materials or solvents in the manufacturing process, requiring more processes, complicated operation, low economic efficiency, strong odor of the prepared polyether product, strong odor of the prepared polyurethane foam, excessive benzene series, etc. Summary of the invention

[0006] Purpose of the invention: The purpose of the present invention is to provide a low-odor phosphazene catalyst with a simple preparation process and low odor;

[0007] The second object of the present invention is to provide the use of the low-odor phosphazene catalyst in polyether polyols and polyurethane foam materials.

[0008] Technical solution: The low-odor phosphazene catalyst of the present invention comprises a phosphazene cation represented by the general formula (I) and an alkali metal salt compound anion;

[0009]

[0010] In the above general formula (I), X represents an alkali metal salt compound, - represents an alkali metal anion formed by the departure of the metal ion in X; wherein X is selected from one of sodium alkoxide, potassium alkoxide, sodium carboxylate, potassium carboxylate, sodium dihydrogen phosphate or potassium dihydrogen phosphate;

[0011] The continuous preparation method of the low-odor phosphazene catalyst comprises the following steps:

[0012] (1) dissolving phosphorus pentahalide in an organic solvent to obtain a phosphorus pentahalide organic solution; slowly dropping a guanidine compound solution into the phosphorus pentahalide organic solution under an inert atmosphere at -15 to 5°C, returning the temperature to room temperature after the dropping is completed, stirring at room temperature, then heating in an oil bath, continuing the reaction, cooling to room temperature after the reaction is completed, filtering, removing precipitates, and obtaining an organic phosphonium salt solution containing the organic solvent and the halogenated phosphorus compound;

[0013] (2) adding an alkali metal salt compound to the organic phosphonium salt solution obtained in step (1), reacting under an inert atmosphere and heating conditions, cooling and filtering after the reaction, and distilling the filtrate under reduced pressure to obtain a crude product of a phosphazene compound;

[0014] The organic solvent is selected from at least one of nitriles or ethers; the alkali metal salt compound is selected from one of sodium alkoxide, potassium alkoxide, sodium carboxylate, potassium carboxylate or metal phosphate.

[0015] Furthermore, the organic solvent is selected from at least one of propionitrile, butyronitrile, adiponitrile, propyl ether, butyl ether or 1,4-dioxane; the alkali metal salt compound is selected from one of potassium methoxide, sodium methoxide, potassium ethoxide, sodium ethoxide, potassium formate, sodium formate, potassium acetate, sodium acetate, potassium dihydrogen phosphate or sodium dihydrogen phosphate.

[0016] Wherein, in the step (1), the phosphorus pentahalide is selected from phosphorus pentabromide or phosphorus pentachloride; and the guanidine compound is 1,1,3,3-tetramethylguanidine.

[0017] Wherein, in the step (1), the mass ratio of phosphorus pentahalide to organic solvent is 1:6-12; the molar ratio of phosphorus pentahalide to guanidine compound is 1:5-11; the temperature is 0-5°C; the temperature of oil bath heating is 80-120°C, and the oil bath is stirred for reaction for 3-8h.

[0018] Wherein, in the step (2), the molar ratio of the organic phosphonium salt solution to the alkali metal salt compound is 1:1-2; the reaction temperature is 50-80°C, the reaction time is 3-8h, and the reaction pressure is normal pressure.

[0019] The crude phosphazene compound obtained in step (2) is recrystallized or slurried for purification.

[0020] Further, the recrystallization step is as follows: recrystallizing the crude phosphazene catalyst product with a purification solvent, filtering, and drying to obtain a white powdery low-odor phosphazene catalyst; the purification solvent is selected from a mixed solution of at least one of nitriles or alcohols and at least one of ethers or alkanes; the volume ratio of at least one of nitriles or alcohols to at least one of ethers or alkanes is 1:2 to 300, preferably 1:50 to 100;

[0021] The slurrying step is as follows: the crude phosphazene catalyst product is slurried with a purification solvent, filtered, and dried to obtain a white powdery low-odor phosphazene catalyst; the purification solvent is selected from a mixed solution of at least one of nitriles or alcohols and at least one of ethers or alkanes; the volume ratio of at least one of nitriles or alcohols to at least one of ethers or alkanes is 1:2-500, preferably 1:100-200.

[0022] The low-odor phosphazene catalyst is used in the preparation of polyether polyols and polyurethane foam materials.

[0023] The low-odor phosphazene catalyst of general formula (I) is mixed with an active hydrogen compound Y and subjected to a heating treatment to obtain a salt of a phosphazene cation and an active hydrogen compound anion represented by general formula (II), which is used to prepare polyether polyols.

[0024]

[0025] In the above general formula (II), n is a real number greater than 0 and less than or equal to 8, Y n- It represents the anion of the active hydrogen compound formed by the departure of n protons in the active hydrogen compound Y; Y is a polyether polyol having a functionality of 2 to 8 and a molecular weight of 300 to 2000.

[0026] Furthermore, n is a real number greater than 0 and less than or equal to 1, and Y is a polyether polyol having a functionality of 2 to 6 and a molecular weight of 400 to 1200.

[0027] Beneficial effects: Compared with the prior art, the present invention achieves the following significant effects:

[0028] (1) The phosphazene catalyst of the present invention uses only one non-benzene inert solvent that does not participate in the reaction during the preparation process, and there is no need to frequently change the solvent. By using the same solvent, the steps of extraction and distillation are reduced, thereby reducing the energy consumption and the generation of wastewater and waste in the process. Through the continuous preparation method of the phosphazene catalyst, a phosphazene catalyst without benzene series can be efficiently prepared, which also plays a positive role in environmental protection. (2) The catalyst synthesized in this way is then purified by pulping or recrystallization, which can make the phosphazene catalyst have lower odor and higher purity. Most importantly, this preparation process provides strong support for the industrial production of phosphazene catalysts. (3) The impurity content of the purified catalyst is low, which can significantly inhibit the small molecular impurities in the polyol prepared subsequently, and at the same time, the odor of the prepared polyurethane foam can also be significantly improved. (4) When the value of n in the general formula (II) is greater than 0 and less than or equal to 1, the proportion of the catalyst in the initiator is small, and the catalyst maintains a high catalytic activity when catalyzing the synthesis of polyethers, which can not only reduce enterprise costs, but also enhance the utilization efficiency of energy, and play a positive role in social energy conservation and emission reduction. DETAILED DESCRIPTION

[0029] The present invention is described in further detail below.

[0030] The sources of relevant raw materials in various embodiments of the present invention are shown in Table 1 below.

[0031] Table 1 List of raw materials

[0032]

[0033] [Example 1]

[0034] (1) Preparation of phosphazene catalyst:

[0035] Step 1: Add 10g of phosphorus pentachloride and 90g of propionitrile solution to a 500ml three-necked flask equipped with a stirrer, a thermometer, and a dropping funnel, and slowly drop 46g of tetramethylguanidine under nitrogen protection, control the reaction temperature at about 0°C, and the reaction pressure at normal pressure. After the dropwise addition is completed, slowly return to room temperature, stir at room temperature for 0.5h, and transfer to an oil bath, stir at 110°C for 3h, cool to room temperature, filter, remove the precipitate, and obtain a solution;

[0036] Step 2: Add 3.7 g of potassium methoxide to the solution obtained in step 1, react at 60° C. and normal pressure for 3 h, cool to room temperature and filter, collect the filtrate and distill under reduced pressure to obtain 23.6 g of unpurified dark oily phosphazene catalyst with a yield of 94.8%.

[0037] (2) Preparation of polyether polyols: 120 g of CHE-307 polyether was added to a 2L autoclave, and the above-mentioned 3.0 g of phosphazene catalyst was added. The reaction mixture was replaced with nitrogen three times, and the mixture was degassed at 105°C and -0.09 MPa for 2 h. At this time, the value of n in the general formula (II) was 0.025. When the pressure in the autoclave was -0.09 MPa and the temperature was 95°C, 1130 g of propylene oxide was added dropwise to carry out polymerization reaction. The reaction mixture was filled with nitrogen and aged until the pressure in the autoclave remained unchanged, and the residual monomers were removed by vacuum negative pressure; and 250 g of ethylene oxide was added dropwise at a slightly positive pressure and a temperature of 105°C for end-capping, and the reaction mixture was filled with nitrogen and aged until the pressure in the autoclave remained unchanged. Pure water and magnesium silicate adsorbent were added, and the mixture was stirred at 105°C for 1 h, and then vacuum negative pressure dehydration was carried out, and the mixture was filtered to obtain the polyether polyol to be prepared.

[0038] (3) Preparation of polyurethane foam material: Preparation of component A: Add 100 parts of the above-mentioned polyether polyol, 1 part of diethanolamine, 2 parts of Dabco NE-1091, 1.5 parts of B-8734, and 3.5 parts of water in container A according to weight percentage, stir for 30 minutes, and prepare component A. Preparation of component B: Add 32.5 parts of Desmodur 3133 to container B, and preheat both A and B materials to 50°C. Pour component A and component B into the mold through a high-pressure foaming machine, or pour them into the mold through a low-pressure foaming machine; set the mold temperature at 50°C, open the mold after 180s, and take it out from the mold to obtain a low-odor polyurethane foam material.

[0039] The performance test data of the prepared phosphazene catalyst, polyether polyol and polyurethane foam material are shown in Tables 3 to 5.

[0040] [Example 2]

[0041] (1) Preparation of phosphazene catalyst:

[0042] Step 1: Add 10g of phosphorus pentachloride and 90g of propionitrile solution to a 500ml three-necked flask equipped with a stirrer, a thermometer, and a dropping funnel, and slowly drop 46g of tetramethylguanidine under nitrogen protection, control the reaction temperature at about 0°C, and the reaction pressure at normal pressure. After the dropwise addition is completed, slowly return to room temperature, stir at room temperature for 0.5h, and transfer to an oil bath, stir at 110°C for 3h, cool to room temperature, filter, remove the precipitate, and obtain a solution;

[0043] Step 2: Add 3.7g of potassium methoxide to the solution obtained in step 1, react at 60°C and normal pressure for 3h, cool to room temperature and filter, collect the filtrate and remove the solvent by vacuum distillation, and recrystallize the concentrate from acetonitrile and cyclohexane, wherein acetonitrile: cyclohexane (v / v) = 1:50, filter, and dry to obtain 19.4g of purified white powdery phosphazene catalyst, with a yield of 78%. The general structural formula of the obtained phosphazene catalyst is shown in the above formula (I).

[0044] (2) Preparation of polyether polyols: 120 g of CHE-307 polyether was added to a 2L autoclave, and the above-mentioned 2.25 g of phosphazene catalyst was added. The reaction mixture was replaced with nitrogen three times, and the mixture was degassed at 105°C and -0.09 MPa for 2 h. At this time, the value of n in the general formula (II) was 0.025. When the pressure in the autoclave was -0.09 MPa and the temperature was 95°C, 1130 g of propylene oxide was added dropwise to carry out polymerization reaction. The reaction mixture was filled with nitrogen and aged until the pressure in the autoclave remained unchanged, and the residual monomers were removed by vacuum negative pressure; and 250 g of ethylene oxide was added dropwise at a slightly positive pressure and a temperature of 105°C for end-capping, and the reaction mixture was filled with nitrogen and aged until the pressure in the autoclave remained unchanged. Pure water and magnesium silicate adsorbent were added, and the mixture was stirred at 105°C for 1 h, and then vacuum negative pressure dehydration was carried out, and the mixture was filtered to obtain the polyether polyol to be prepared.

[0045] (3) Preparation of polyurethane foam material: Preparation of component A: Add 100 parts of the above-mentioned polyether polyol, 1 part of diethanolamine, 2 parts of Dabco NE-1091, 1.5 parts of B-8734, and 3.5 parts of water in container A according to weight percentage, and stir for 30 minutes to prepare component A. For component B, add 32.5 parts of Desmodur 3133 in container B, and preheat both A and B materials to 50°C. Pour component A and component B into a mold through a high-pressure foaming machine, or pour them into a mold through a low-pressure foaming machine, set the mold temperature at 50°C, open the mold after 180 seconds, and take them out from the mold to obtain a low-odor polyurethane foam material.

[0046] The performance test data of the prepared phosphazene catalyst, polyether polyol and polyurethane foam material are shown in Tables 3 to 5.

[0047] [Examples 3 to 12]

[0048] Examples 3 to 12 are carried out according to the steps of Example 2, except that the relevant formulas of the phosphazene catalysts are different. The specific formulas and relevant conditions are shown in Table 2; the performance test data of the prepared phosphazene catalysts, polyether polyols and polyurethane foam materials are shown in Tables 3 to 5.

[0049] [Comparative Example 1]

[0050] Comparative Example 1 is to prepare a phosphazene catalyst using toluene as solvent according to Example 1 in Patent No. CN104497046B;

[0051] [Comparative Example 2]

[0052] Comparative Example 2 is to prepare the phosphazene catalyst using toluene according to Synthesis Example 1 of Patent: CN102171272B;

[0053] [Comparative Example 3]

[0054] Comparative Example 3 is to prepare the phosphazene catalyst using toluene according to the method of Examples 1, 2 and 5 of Patent No. DE102006010034.

[0055] The preparation steps of the relevant phosphazene catalysts obtained in Comparative Examples 1 to 3 and applied to polyether polyols and polyurethane foam materials are consistent with those in Examples 1 to 12. The performance test data of the phosphazene catalysts, polyether polyols and polyurethane foam materials are shown in Tables 3 to 5.

[0056] Table 2 Specific formulations and related conditions of Examples 1 to 12

[0057]

[0058]

[0059] Table 3 Data results of phosphazene catalysts of Examples 1 to 12 and Comparative Examples 1 to 3 (unit: ug / m 3 )

[0060]

[0061] Table 4 Data results of polyether polyols prepared by catalysts of Examples 1 to 12 and Comparative Examples 1 to 3 (unit: ug / m 3 )

[0062]

[0063] Table 5 Data results of polyurethane foam materials prepared from polyols of Examples 1 to 12 and Comparative Examples 1 to 3 (unit: ug / m 3 )

[0064]

[0065] Note: In the above table, the odor level is measured according to the VDA270 standard of the automotive industry. The foam data is measured at 65°C using a 10L bag method: the detection limit of benzene is 11.342ug / m 3 The detection limit of aldehydes and ketones is 18.903ug / m 3 The data of raw materials such as catalysts and polyether polyols were measured at 80°C using a 10L bag method: the detection limit of benzene series was 11.845ug / m 3 The detection limit of aldehydes and ketones is 19.742ug / m 3 .

Claims

1. A low-odor phosphazene catalyst, characterized in that: Comprising a phosphazene cation represented by the general formula (I) and an alkali metal salt compound anion; In the above general formula (I), X represents an alkali metal salt compound, - represents an alkali metal anion formed by the departure of the metal ion in X; wherein X is selected from one of sodium alkoxide, potassium alkoxide, sodium carboxylate, potassium carboxylate or metal phosphate; The continuous preparation method of the low-odor phosphazene catalyst comprises the following steps: (1) dissolving phosphorus pentahalide in an organic solvent to obtain a phosphorus pentahalide organic solution; slowly dropping a guanidine compound solution into the phosphorus pentahalide organic solution under an inert atmosphere at -15 to 5°C, returning the temperature to room temperature after the dropping is completed, stirring at room temperature, then heating in an oil bath, continuing the reaction, cooling to room temperature after the reaction is completed, filtering, removing precipitates, and obtaining an organic phosphonium salt solution containing the organic solvent and the halogenated phosphorus compound; (2) adding an alkali metal salt compound to the organic phosphonium salt solution obtained in step (1), reacting under an inert atmosphere and heating conditions, cooling and filtering after the reaction, and distilling the filtrate under reduced pressure to obtain a crude product of a phosphazene compound; The organic solvent is selected from at least one of nitriles or ethers; the alkali metal salt compound is selected from one of sodium alkoxide, potassium alkoxide, sodium carboxylate, potassium carboxylate or metal phosphate.

2. The low-odor phosphazene catalyst according to claim 1, characterized in that The organic solvent is selected from at least one of propionitrile, butyronitrile, adiponitrile, propyl ether, butyl ether or 1,4-dioxane; the alkali metal salt compound is selected from one of potassium methoxide, sodium methoxide, potassium ethoxide, sodium ethoxide, potassium formate, sodium formate, potassium acetate, sodium acetate, potassium dihydrogen phosphate or sodium dihydrogen phosphate.

3. The low-odor phosphazene catalyst according to claim 1, characterized in that In the step (1), the mass ratio of phosphorus pentahalide to organic solvent is 1:6-12; the molar ratio of phosphorus pentahalide to guanidine compound is 1:5-11; the temperature is 0-5°C; the temperature of oil bath heating is 80-120°C, and the oil bath is stirred for reaction for 3-8h.

4. The low-odor phosphazene catalyst according to claim 1, characterized in that In the step (2), the molar ratio of the organic phosphonium salt solution to the alkali metal salt compound is 1:1-2; the reaction temperature is 50-80°C, and the reaction time is 3-8h.

5. The low-odor phosphazene catalyst according to claim 1, characterized in that In step (1), the phosphorus pentahalide is selected from phosphorus pentabromide or phosphorus pentachloride; and the guanidine compound is 1,1,3,3-tetramethylguanidine.

6. The low-odor phosphazene catalyst according to claim 1, characterized in that Recrystallize or slurry the crude phosphazene compound obtained in step (2) for purification; The recrystallization step is as follows: recrystallizing the crude phosphazene catalyst product with a purification solvent, filtering, and drying to obtain a white powdery low-odor phosphazene catalyst; the purification solvent is selected from a mixed solution of at least one of nitriles or alcohols and at least one of ethers or alkanes; the volume ratio of at least one of nitriles or alcohols to at least one of ethers or alkanes is 1:2-300; The slurrying step is as follows: the crude phosphazene catalyst product is slurried with a purification solvent, filtered, and dried to obtain a white powdery low-odor phosphazene catalyst; the purification solvent is selected from a mixed solution of at least one of nitriles or alcohols and at least one of ethers or alkanes; the volume ratio of at least one of nitriles or alcohols to at least one of ethers or alkanes is 1:2-500.

7. Use of the low-odor phosphazene catalyst according to claim 1 in the preparation of polyether polyols and polyurethane foam materials.

8. Use of the low-odor phosphazene catalyst according to claim 7 in the preparation of polyether polyols and polyurethane foam materials, characterized in that: The phosphazene catalyst represented by the general formula (I) is mixed with the active hydrogen compound Y and subjected to a heat treatment to obtain a salt of the phosphazene cation represented by the general formula (II) and the active hydrogen compound anion. In the above general formula (II), n is a real number greater than 0 and less than or equal to 8, Y n- It represents the anion of the active hydrogen compound formed by the departure of n protons in the active hydrogen compound Y; Y is a polyether polyol having a functionality of 2 to 8 and a molecular weight of 300 to 2000.

9. Use of the low-odor phosphazene catalyst according to claim 8 in the preparation of polyether polyols and polyurethane foam materials, characterized in that: The n is a real number greater than 0 and less than or equal to 1, and Y is a polyether polyol with a functionality of 2 to 6 and a molecular weight of 400 to 1200.

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