Gas phase detection method for hexafluorocyclotriphosphazene etherification reaction product

Abstract

The invention relates to the technical field of gas chromatographic analysis, in particular to a gas phase detection method for a hexafluorocyclotriphosphazene etherification reaction product. Comprising the following steps: 1) sampling, 2) detection: performing gas chromatography detection on a to-be-detected sample solution under the heating condition of a chromatographic column A and the heating condition of a chromatographic column B. The method is simple to operate, relatively low in cost, accurate and efficient, and can accurately and rapidly obtain a product of an etherification reaction of hexafluorocyclotriphosphazene at room temperature; the method can be used for analyzing and detecting pentafluoro (ethyoxyl) cyclotriphosphazene and series products, and is particularly suitable for accurately detecting pentafluoro (ethyoxyl) cyclotriphosphazene series reaction liquid series products in the products obtained by the existing synthetic route.

Description

Technical Field

[0001] The invention relates to the technical field of gas chromatography analysis, in particular to a gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products. Background Art

[0002] The synthesis route of the hexafluorocyclotriphosphazene etherification reaction product is as follows: hexachlorocyclotriphosphazene is first subjected to a fluorination reaction with sodium fluoride to obtain a reaction solution containing hexafluorocyclotriphosphazene; the obtained reaction solution containing hexafluorocyclotriphosphazene is then subjected to an etherification reaction with an etherifying agent at room temperature to obtain the hexafluorocyclotriphosphazene etherification reaction product. The process is as follows: The structural formulas of the obtained hexafluorocyclotriphosphazene etherification reaction product are shown in the following formulas (1) and (2):

[0003] In formula (1), it is a pentafluorocyclotriphosphazene series reaction solution, and R is selected from methyl, ethyl, trifluoroethyl, difluoroethyl, monofluoroethyl, benzyl, and phenyl. In formula (2), R is selected from methyl, which is a hexamethoxycyclotriphosphazene reaction solution.

[0004] The above-mentioned products are mainly new phosphazene flame retardants, represented by pentafluoro(ethoxy)cyclotriphosphazene and phenoxypentafluorocyclotriphosphazene. They have the properties of high flame retardant efficiency, good thermal stability, low toxicity and little environmental damage, and have huge market potential in the future.

[0005] Pentafluoro(ethoxy)cyclotriphosphazene (CAS: 33027-66-6) is designed as a flame retardant additive for lithium battery electrolytes. As a novel phosphazene compound, it can be added in small quantities to the electrolyte. It exhibits excellent flame retardancy and has little impact on other battery performance, making it an ideal lithium-ion electrolyte additive. Pentafluoro(ethoxy)cyclotriphosphazene, when added in small amounts to lithium battery electrolytes, can inhibit discoloration and improve battery safety.

[0006] To ensure the safety performance of the battery and its instructions for use, the purity of the additives in the battery electrolyte must be extremely high. Therefore, the detection accuracy requirements for the purity and effective ingredient content of the flame retardant additives for the battery are also high. At least the same sample must be tested three times, and the difference between the measurement results must be less than 0.009.

[0007] "Progress in Characterization Technology of Cyclotriphosphazene and Its Derivatives" briefly describes the basic standard methods for cyclotriphosphazene and its derivatives, including: Fourier transform infrared spectroscopy, nuclear magnetic resonance, mass spectrometry, chromatography, thermal analysis, etc., among which there are relatively few qualitative and quantitative analysis methods for the products.

[0008] CN202210552904.X discloses an analysis method for alkoxy (pentafluoro) cyclotriphosphazene. This method uses a gas chromatography-mass spectrometer (GC-MS). This method can better analyze and detect alkoxy (pentafluoro) cyclotriphosphazene and its impurities. However, the use and maintenance costs of the GC-MS are high, making it difficult to implement in general laboratories and production work.

[0009] For example, CN202410775909.8 discloses a method and application for the simultaneous detection of hexachlorocyclotriphosphazene, hexafluorocyclotriphosphazene, and ethoxypentafluorocyclotriphosphazene. This method uses gas chromatography-mass spectrometry for detection, using acetone as a diluent to dissolve the sample to be tested; the sample to be tested includes one or more of hexachlorocyclotriphosphazene, hexafluorocyclotriphosphazene, and ethoxypentafluorocyclotriphosphazene; based on the gas chromatography results, the content of hexachlorocyclotriphosphazene, hexafluorocyclotriphosphazene, and ethoxypentafluorocyclotriphosphazene in the sample to be tested is determined by an external standard method or an area normalization method. This method is not applicable to the direct and accurate detection of products containing pentafluoro(ethoxy)cyclotriphosphazene prepared by the above-mentioned existing methods, and focuses on the simultaneous detection of hexachlorocyclotriphosphazene, hexafluorocyclotriphosphazene, and ethoxypentafluorocyclotriphosphazene. It cannot be used for the detection of a series of products, and the detection objects are limited.

[0010] Since the products obtained by the above methods have complex components and are mixed with various by-products and incompletely reacted substances produced during the reaction, all of which will affect the accuracy of the detection results, there is currently a lack of methods that can directly be used to accurately detect the products of the hexafluorocyclotriphosphazene etherification reaction. Summary of the Invention

[0011] In order to solve the above problems, the present invention provides a gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products. The method is simple to operate, relatively low in cost, accurate and efficient, and can accurately and quickly analyze and detect the hexafluorocyclotriphosphazene etherification reaction products. It is particularly suitable for accurately detecting the hexafluorocyclotriphosphazene etherification reaction product obtained by first performing a fluorination reaction on hexachlorocyclotriphosphazene with sodium fluoride in the existing synthesis route, and then performing an etherification reaction on the obtained hexafluorocyclotriphosphazene-containing reaction liquid with an etherifying agent at room temperature.

[0012] The scheme of the present invention is: A gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products comprises the following steps: 1) taking a sample, diluting the test sample with a diluent, fixing the volume to obtain a test solution, and shaking to obtain a test sample solution; the test sample is a product of an etherification reaction of hexafluorocyclotriphosphazene at room temperature, and is any one of a reaction solution containing pentafluoro(ethoxy)cyclotriphosphazene, a reaction solution containing pentafluoro(methoxy)cyclotriphosphazene, a reaction solution containing pentafluoro(trifluoroethoxy)cyclotriphosphazene, a reaction solution containing pentafluoro(difluoroethoxy)cyclotriphosphazene, a reaction solution containing pentafluoro(monofluoroethoxy)cyclotriphosphazene, a reaction solution containing pentafluoro(benzyloxy)cyclotriphosphazene, a reaction solution containing pentafluoro(phenoxy)cyclotriphosphazene, and a reaction solution containing hexamethoxycyclotriphosphazene; 2) Detection, subjecting the sample solution to be tested to gas chromatography detection, wherein the gas chromatography detection is performed under one of the temperature increase conditions of chromatographic column A and chromatographic column B, wherein the temperature increase condition of chromatographic column A is as follows: a starting temperature of 30-60° C., maintained for 3-6 minutes, raised to 160-180° C. at a rate of 15-25° C. / min, maintained for 0-5 minutes, raised to 160-180° C. at a rate of 15-50° C. / min, maintained for 0-5 minutes, and then raised to 220-250° C. at a rate of 30-50° C. / min; The heating conditions of column B are as follows: starting temperature 50-80°C, maintaining for 0-3 min, increasing to 160-180°C at a rate of 15-25°C / min, maintaining for 0-5 min, increasing to 160-180°C at a rate of 15-25°C / min, maintaining for 0-5 min, and then increasing to 250-280°C at a rate of 30-50°C / min.

[0013] As a preferred technical solution, the detector temperature of the gas chromatography detection is 240-290°C; the injection port temperature is 240-300°C; the carrier gas is nitrogen; the column flow rate is 1-2 mL / min; the split ratio is 25-35:1; The hydrogen flow rate was 40 mL / min; the air flow rate was 400 mL / min; and the tail gas flow rate was 25 mL / min.

[0014] As a preferred technical solution, the diluent is any one or more of methanol, acetonitrile, ethyl acetate, tetrahydrofuran, dichloromethane and ethanol.

[0015] As a preferred technical solution, the front detector used for gas phase determination in the gas chromatography detection is a FID detector.

[0016] As a preferred technical solution, the injection volume of the sample solution to be tested in step 1) is 1 μL.

[0017] As a preferred technical solution, the sample concentration in the sample solution to be tested is 5 mg / mL to 100 mg / mL.

[0018] As a preferred technical solution, the heating conditions of chromatographic column A are as follows: starting temperature 30°C, keeping for 6 minutes, heating to 180°C at 20°C / min and keeping for 1 minute, then heating from 180°C to 250°C at a heating rate of 50°C / min, keeping for 4.5 minutes to complete the sample. The total running time of the heating program is 20.4 minutes.

[0019] As a preferred technical solution, the heating conditions of chromatographic column B are as follows: starting temperature 60°C, maintaining for 3 minutes, heating to 180°C at 20°C / min, then heating to 250°C at 50°C / min, and maintaining for 5 minutes. The total running time of the heating program is 15.4 minutes.

[0020] As a preferred technical solution, the chromatographic column in the gas chromatography detection in step 2) is one of a DB-1 gas chromatography column or an HP-5 gas chromatography column; the parameters of the DB-1 gas chromatography column are Agilent 122-1022, 25m×250μm×0.25μm; the parameters of the HP-5 gas chromatography column are 25m×250μm×0.25μm.

[0021] Advantages of the present invention: 1. The gas phase detection method provided herein can rapidly and accurately analyze and determine the content of pentafluoro(ethoxy)cyclotriphosphazene in a prepared product containing pentafluoro(ethoxy)cyclotriphosphazene. This method provides qualitative and quantitative analysis of pentafluoro(ethoxy)cyclotriphosphazene, offering excellent resolution, ease of operation, short run times, and accurate results. The gas phase detection method can determine the specific content of pentafluoro(ethoxy)cyclotriphosphazene in a sample by integrating the peak area, facilitating rapid detection in large-scale industrial production.

[0022] 2) The method provided in this application can effectively detect the content of pentafluoro(ethoxy)cyclotriphosphazene in the reaction solution, and the relative error between the measured result and the theoretical concentration is only 0.35%, indicating that this method has high detection accuracy for pentafluoro(ethoxy)cyclotriphosphazene.

[0023] 3) This method can also be used to detect hexafluorocyclotriphosphazene etherification reaction products, such as pentafluoro(methoxy)cyclotriphosphazene reaction solutions, pentafluoro(trifluoroethoxy)cyclotriphosphazene, pentafluoro(difluoroethoxy)cyclotriphosphazene, pentafluoro(monofluoroethoxy)cyclotriphosphazene, pentafluoro(benzyloxy)cyclotriphosphazene, pentafluoro(phenoxy)cyclotriphosphazene, and hexamethoxycyclotriphosphazene reaction solutions. The detection results show excellent impurity peak separation and good peak shape. This method has a wide range of applications and can detect the above-mentioned substances in reaction solutions. It facilitates the timely determination of the actual main components in reaction solutions during large-scale industrial production, facilitating timely adjustments to the industrial production process based on this information. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is the chromatogram of Example 1 of the present invention; Figure 2 is the chromatogram of Example 2 of the present invention; FIG3 is a graph showing the gas chromatography detection results of each test solution in Example 3 of the present invention.

[0025] Figure 4 This is a graph showing the linearity test results of the working curve of the pentafluoro(ethoxy)cyclotriphosphazene standard solution obtained in Example 4 of the present invention; Figure 5 This is the area percentage chromatogram of Example 6 of the present invention; Figure 6 It is the external standard method chromatogram of Example 6 of the present invention. DETAILED DESCRIPTION

[0026] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below in conjunction with specific embodiments.

[0027] Unless otherwise specified, the materials and instruments used in the following examples were obtained from commercial channels; the detection methods used were all existing methods unless otherwise specified.

[0028] The reaction solutions used in the following examples were prepared according to the following methods, wherein the reaction parameters not described in detail were set according to the parameters disclosed in the existing material preparation methods: 5 g of hexachlorocyclotriphosphazene and sodium fluoride are subjected to a fluorination reaction under heating conditions to obtain a hexafluorocyclotriphosphazene-containing product; the obtained hexafluorocyclotriphosphazene-containing product is subjected to an etherification reaction with ethanol at room temperature to obtain a pentafluoro(ethoxy)cyclotriphosphazene reaction solution.

[0029] The difference between the preparation method of pentafluoro(methoxy)cyclotriphosphazene reaction solution and the preparation method of pentafluoro(ethoxy)cyclotriphosphazene reaction solution is that methanol is used as the etherifying agent for the reaction; The difference between the method for preparing the reaction solution of pentafluoro(trifluoroethoxy)cyclotriphosphazene and the method for preparing the reaction solution of pentafluoro(ethoxy)cyclotriphosphazene is that trifluoroethanol is used as the etherifying agent for the reaction; The difference between the preparation method of the reaction solution of pentafluoro(difluoroethoxy)cyclotriphosphazene and the preparation method of the reaction solution of pentafluoro(ethoxy)cyclotriphosphazene is that difluoroethanol is used as the etherifying agent for the reaction; The difference between the method for preparing a pentafluoro(monofluoroethoxy)cyclotriphosphazene reaction solution and the method for preparing a pentafluoro(ethoxy)cyclotriphosphazene reaction solution is that: monofluoroethanol is used as an etherifying agent for the reaction; The difference between the preparation method of pentafluoro(benzyloxy)cyclotriphosphazene reaction solution and the preparation method of pentafluoro(ethoxy)cyclotriphosphazene reaction solution is that benzyl alcohol is used as the etherifying agent for the reaction; The difference between the preparation method of the reaction solution of pentafluoro(phenoxy)cyclotriphosphazene and the preparation method of the reaction solution of pentafluoro(ethoxy)cyclotriphosphazene is that phenol is used as the etherifying agent in the reaction; The difference between the method for preparing the hexamethoxycyclotriphosphazene reaction solution and the method for preparing the pentafluoro(ethoxy)cyclotriphosphazene reaction solution is that the ethoxylation reaction is directly carried out using hexachlorocyclotriphosphazene as a raw material and methanol as an etherifying agent.

[0030] Example 1 Prepare the test solution: Accurately weigh 5 g of the pentafluoro(ethoxy)cyclotriphosphazene reaction solution as the sample and place it in a 50 mL volumetric flask. Dissolve and dilute the sample with acetonitrile as the diluent, then bring the volume to the mark. Prepare a test solution with a concentration of 20-100 mg / mL and shake well to obtain the test solution. Analyze the test solution using an Agilent 8860 gas chromatography system under the conditions listed in Table 1. Repeat the analysis three times for the same sample. Gas chromatography uses an FID detector as the front detector.

[0031] Table 1 Gas chromatography detection conditions of Example 1

[0032] The gas chromatography test results of the sample in this embodiment are as follows: Figure 1 As shown, the resolution between the main product peak (RT = 6.998 min) and the impurity peak (RT = 8.661 min) is 31.98, indicating good resolution and good peak shape. The difference between the results of three repeated assays was less than 0.009.

[0033] Example 2 The difference from Example 1 is that the test solution is subjected to gas chromatography detection according to the conditions in Table 2. The front detector used in gas chromatography determination is FID detector.

[0034] Table 2 Gas chromatography conditions of Example 2

[0035] The gas chromatography conditions of this embodiment are basically the same as those of Example 1, except that the column temperature is increased in a different manner. The gas chromatography test results obtained in this embodiment are as follows: Figure 2 As shown in the figure, the separation degree between the main product peak (RT = 2.978 min) and the impurity peak (RT = 4.498 min) is 33.78, with good separation and good peak shape. The use of this temperature program can achieve a stable baseline of the obtained spectrum, fewer small impurity peaks, and faster analysis and detection of samples.

[0036] The same sample was tested three times under this condition, and the difference between the three test results was less than 0.009.

[0037] Example 3 Prepare the test solution: weigh 1 ml each of pentafluoro(methoxy)cyclotriphosphazene reaction solution, pentafluoro(trifluoroethoxy)cyclotriphosphazene reaction solution, pentafluoro(difluoroethoxy)cyclotriphosphazene reaction solution, pentafluoro(monofluoroethoxy)cyclotriphosphazene reaction solution, pentafluoro(benzyloxy)cyclotriphosphazene reaction solution, pentafluoro(phenoxy)cyclotriphosphazene reaction solution, and hexamethoxycyclotriphosphazene reaction solution, place the samples in volumetric flasks, dissolve them in acetonitrile and dilute to the scale, prepare the test solution with a concentration of 30 mg / mL, shake well to obtain multiple test solutions.

[0038] According to the gas chromatography conditions in Example 1, the pentafluoro(methoxy)cyclotriphosphazene test solution, the pentafluoro(trifluoroethoxy)cyclotriphosphazene test solution, the pentafluoro(difluoroethoxy)cyclotriphosphazene test solution, and the pentafluoro(benzyloxy)cyclotriphosphazene test solution were analyzed and detected.

[0039] The pentafluoro(monofluoroethoxy)cyclotriphosphazene test solution, the pentafluoro(phenoxy)cyclotriphosphazene test solution, and the hexamethoxycyclotriphosphazene test solution were analyzed and tested according to the gas chromatography conditions in Example 2.

[0040] The gas chromatography test results of each test solution are shown in the figure Figures 3a-3h As shown, pentafluoro(methoxy)cyclotriphosphazene (RT = 4.445 min), pentafluoro(trifluoroethoxy)cyclotriphosphazene (RT = 3.634 min), pentafluoro(difluoroethoxy)cyclotriphosphazene (RT = 6.789 min), pentafluoro(monofluoroethoxy)cyclotriphosphazene (RT = 3.850 min), pentafluoro(benzyloxy)cyclotriphosphazene (RT = 12.411 min), pentafluoro(phenoxy)cyclotriphosphazene (RT = 8.745 min), and hexamethoxycyclotriphosphazene (RT = 13.957 min) were well separated from the impurity peaks in the reaction solution, and the peak shapes were good. This demonstrates that the detection method can achieve accurate detection of the above-mentioned reaction solutions.

[0041] Example 4 Accurately weigh pentafluoro(ethoxy)cyclotriphosphazene standard and prepare five or more standard solutions with different concentrations of peak substance within the range of 1 to 50 mg / mL by stepwise dilution of the standard stock solution; The obtained standard solution was measured according to the corresponding concentration in Table 3 using the same gas chromatography conditions as in Table 2. Each sample of the standard curve sample solutions 1-7 was measured twice in parallel. The specific results are shown in Table 3 below: Table 3 Test results of pentafluoro(ethoxy)cyclotriphosphazene standard solution content

[0042] Select the content test results in Table 3 to draw one, two or more standard curves to configure a series of standard working solutions, with mass concentration as the horizontal axis (X) and peak area as the vertical axis (Y). Use gas chromatograph to draw the working curve y=67.6723456*x-24.942948, with a correlation coefficient of 0.99976. The working curve of the standard solution (such as Figure 4 ) The specific results are shown in Table 4 below: Table 4 Overview of working curve of pentafluoro(ethoxy)cyclotriphosphazene standard solution

[0043] As can be seen from Table 3, the deviations of the standard sample of pentafluoro(ethoxy)cyclotriphosphazene detected by the method provided by the present application are small, indicating that the detection results of pentafluoro(ethoxy)cyclotriphosphazene by this method are reliable and accurate.

[0044] Depend on Figure 4 It can be seen that the linear relationship between the results of the linear gradient dilution standard measured using this method is obvious, indicating that this method has high accuracy in monitoring pentafluoro(ethoxy)cyclotriphosphazene.

[0045] Example 5 This example conducts an experiment to determine the content of pentafluoro(ethoxy)cyclotriphosphazene. The specific steps are as follows: Prepare the solution: Accurately weigh the pentafluoro(ethoxy)cyclotriphosphazene standard into the acetonitrile solution for gas chromatography detection, place it in a volumetric flask, dissolve it with chromatographic acetonitrile and dilute to the scale to prepare a test solution with a concentration of 5.23 mg / mL, shake well to obtain the test solution, and take 1 mL into a sample bottle.

[0046] The same chromatographic conditions as in Example 2 were used to determine the content of pentafluoro(ethoxy)cyclotriphosphazene. The sample solution was tested and the peaks in the chromatogram were integrated. The standard curve in Example 3 was used for calculation.

[0047] Five parallel sample tests were performed and the average value was taken. The test concentrations of pentafluoro(ethoxy)cyclotriphosphazene and its series products were basically consistent with the theoretical concentrations. The specific results are shown in Table 5 below: Table 5 Pentafluoro(ethoxy)cyclotriphosphazene content test results

[0048] As can be seen from Table 5, the method provided in this application can effectively detect the content of pentafluoro(ethoxy)cyclotriphosphazene in the reaction solution, and the relative error between the measured result and the theoretical concentration is only 0.35%, indicating that this method has a high detection accuracy for pentafluoro(ethoxy)cyclotriphosphazene.

[0049] Example 6 This example conducts an experiment to determine the content of crude pentafluoro(ethoxy)cyclotriphosphazene. The specific steps are as follows: The pentafluoro(ethoxy)cyclotriphosphazene reaction solution is subjected to rectification and purification to obtain a crude pentafluoro(ethoxy)cyclotriphosphazene product.

[0050] Prepare the solution: Accurately weigh the crude pentafluoro(ethoxy)cyclotriphosphazene and dissolve it in the chromatographic acetonitrile solution. Place it in a volumetric flask and dilute it to the mark with chromatographic acetonitrile to prepare a test solution with a concentration of 37.81 mg / mL. Shake well to obtain the test solution and transfer 1 mL into a sample bottle.

[0051] The same chromatographic conditions as in Example 2 were used to determine the content of pentafluoro(ethoxy)cyclotriphosphazene in the obtained test solution. The gas chromatography results obtained by detecting the sample solution and integrating the peaks in the chromatogram were as follows: Figure 5 As shown; The chromatographic purity of the crude pentafluoro(ethoxy)cyclotriphosphazene was 98.14% as measured by the peak area percentage method. The standard curve in Example 4 was used for calculation according to the common method in the field of chromatographic detection. The gas chromatographic purity was 98.14%. Figure 6 As shown, the crude pentafluoro(ethoxy)cyclotriphosphazene content in the test solution was measured to be 36.86 mg / mL, and the calculated pentafluoro(ethoxy)cyclotriphosphazene content in the crude product was 97.50%. This method can be used to determine the actual pentafluoro(ethoxy)cyclotriphosphazene content in the reaction solution, facilitating its application in large-scale industrial production.

[0052] Example 7 The difference from Example 2 is that the column temperature rising conditions are as follows: starting temperature 50°C, maintaining for 3 min, increasing to 160°C at a rate of 15°C / min, maintaining for 1 min, increasing to 160°C at a rate of 15°C / min, maintaining for 1 min, and then increasing to 220°C at a rate of 50°C / min; The diluent for the test solution is a mixture of methanol and ethyl acetate in a volume ratio of 1:1.

[0053] The sample concentration in the test solution was 100 mg / mL.

[0054] The detector temperature was 240°C; the injection port temperature was 240°C; the carrier gas was nitrogen; the column flow rate was 1 mL / min; and the split ratio was 25:1.

[0055] Example 8 The difference from Example 2 is that the column temperature rising conditions are as follows: starting temperature 80°C, maintaining for 3 min, increasing to 180°C at a rate of 25°C / min, maintaining for 5 min, increasing to 180°C at a rate of 50°C / min, maintaining for 5 min, and then increasing to 250°C at a rate of 30°C / min; The diluent for the test solution was tetrahydrofuran.

[0056] The sample concentration in the test solution was 5 mg / mL.

[0057] The detector temperature was 290°C; the injection port temperature was 300°C; the carrier gas was nitrogen; the column flow rate was 2 mL / min; and the split ratio was 35:1.

[0058] Example 9 The difference from Example 2 is that the temperature is raised to 170°C at a rate of 25°C / min, maintained for 5 minutes, and then raised to 280°C at a rate of 40°C / min; The diluent for the test solution is a mixture of dichloromethane and ethanol in a volume ratio of 1:1.

[0059] The chromatographic column parameters are HP-5, 25m×250μm×0.25μm.

[0060] Example 10 The difference from Example 2 is that the column temperature is: starting temperature 60°C, kept for 3 minutes, heated to 180°C at a rate of 10°C / min, then heated from 180°C to 250°C at a rate of 50°C / min, and kept for 3 minutes to complete the sample.

[0061] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art will appreciate that the present invention is not limited to the foregoing embodiments and that various modifications and improvements may be made to the present invention without departing from the spirit and scope of the present invention, all of which are intended to be protected. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products, characterized in that: The following steps are involved: Sampling, diluting the test sample with a diluent, fixing the volume to obtain a test solution, and shaking to obtain a test sample solution; the test sample is a product of an etherification reaction of hexafluorocyclotriphosphazene at room temperature, and is any one of a reaction solution containing pentafluoro(ethoxy)cyclotriphosphazene, a reaction solution containing pentafluoro(methoxy)cyclotriphosphazene, a reaction solution containing pentafluoro(trifluoroethoxy)cyclotriphosphazene, a reaction solution containing pentafluoro(difluoroethoxy)cyclotriphosphazene, a reaction solution containing pentafluoro(monofluoroethoxy)cyclotriphosphazene, a reaction solution containing pentafluoro(benzyloxy)cyclotriphosphazene, a reaction solution containing pentafluoro(phenoxy)cyclotriphosphazene, and a reaction solution containing hexamethoxycyclotriphosphazene; Detection, the sample solution to be tested is subjected to gas chromatography detection, and the gas chromatography detection is one of the heating conditions of the chromatographic column A and the heating conditions of the chromatographic column B, the heating condition of the chromatographic column A is as follows: the starting temperature is 30-60°C, maintained for 3-6 minutes, increased to 160-180°C at a rate of 15-25°C / min, maintained for 0-5 minutes, increased to 160-180°C at a rate of 15-50°C / min, maintained for 0-5 minutes, and then increased to 220-250°C at a rate of 30-50°C / min; The heating conditions of column B are as follows: starting temperature 50-80°C, maintaining for 0-3 min, increasing to 160-180°C at a rate of 15-25°C / min, maintaining for 0-5 min, increasing to 160-180°C at a rate of 15-25°C / min, maintaining for 0-5 min, and then increasing to 250-280°C at a rate of 30-50°C / min.

2. A gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products according to claim 1, characterized in that: The detector temperature of the gas chromatography detection is 240-290° C.; the injection port temperature is 240-300° C.; the carrier gas is nitrogen; the chromatographic column flow rate is 1-2 mL / min; and the split ratio is 25-35:

1.

3. The gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products according to claim 1, characterized in that: The diluent is any one or more of methanol, acetonitrile, ethyl acetate, tetrahydrofuran, dichloromethane and ethanol.

4. A gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products according to claim 1, characterized in that: The front detector used for gas phase determination in the gas chromatography detection is a FID detector.

5. The gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products according to claim 1, characterized in that: In step 1), the injection volume of the sample solution to be tested is 1 μL.

6. A gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products according to claim 5, characterized in that: The sample concentration in the sample solution to be tested is 5 mg / mL to 100 mg / mL.

7. A gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products according to claim 1, characterized in that: The heating conditions of chromatographic column A are as follows: starting temperature 30℃, keeping for 6 minutes, heating to 180℃ at 20℃ / min and keeping for 1 minute, then heating from 180℃ to 250℃ at a heating rate of 50℃ / min, keeping for 4.5 minutes to complete the sample. The total running time of the heating program is 20.4 minutes.

8. A gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products according to claim 1, characterized in that: The heating conditions of column B were as follows: starting temperature at 60°C, maintaining for 3 min, heating to 180°C at 20°C / min, then heating to 250°C at 50°C / min, and maintaining for 5 min. The total running time of the heating program was 15.4 min.

9. A gas phase detection method for hexafluorocyclotriphosphazene etherification reaction products according to claim 1, characterized in that: The chromatographic column in the gas chromatography detection in step 2) is one of a DB-1 gas chromatography column or an HP-5 gas chromatography column; the parameters of the DB-1 gas chromatography column are Agilent 122-1022, 25m×250μm×0.25μm; the parameters of the HP-5 gas chromatography column are 25m×250μm×0.25μm.

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