Methods for detecting diamine compounds in tile grout

Abstract

This application discloses a method for detecting the content of diamine compounds in tile grout. The method includes: mixing, diluting, and derivatizing diamine compound standards with solvents to obtain standard solutions of diamine derivatives at various concentrations; testing the standard solutions of diamine derivatives at various concentrations in a chromatograph and obtaining a standard working curve after fitting; mixing, diluting, and derivatizing a test sample containing the diamine compounds with a solvent to obtain a derivatized test sample solution; testing the derivatized test sample solution in a chromatograph to obtain the area of ​​the chromatographic peak of the diamine compounds, then obtaining the concentration of the diamine compounds, and finally obtaining the content of the diamine compounds in the test sample. According to the embodiments of this application, the content of multiple diamine compounds can be detected simultaneously and accurately.

Description

Technical Field

[0001] This application belongs to the field of detection technology, and in particular relates to a method for detecting the content of diamine compounds in tile grout. Background Technology

[0002] 1,6-Hexanediamine, as an important organic chemical intermediate, is widely used as a raw material for the synthesis of polyamides, and is also commonly used as a curing agent and crosslinking agent for urea resins and epoxy resins. 1,3-Cyclohexanedimethylamine, as an important fine chemical and organic chemical intermediate, is used in epoxy resin curing agents, isocyanates, composite materials (wind turbine blades, automobiles), stone materials, floor coatings, adhesives, and other fields due to its characteristics such as fast curing speed, low active hydrogen equivalent, good water resistance, low viscosity, and low toxicity. 1,3-Propanediamine is used as an organic synthesis intermediate and solvent, and is also used in the synthesis of pharmaceuticals and pesticides. It is an auxiliary raw material in the paper, textile, and leather industries, and is also used in the synthesis of epoxy resin curing agents, synthetic fuel oils, and lubricant additives. While tile grout originally does not contain 1,6-hexanediamine and 1,3-propanediamine, unscrupulous manufacturers may introduce these substances to reduce costs by using inferior raw materials. In addition, the amount of 1,3-cyclohexanedimethylamine added, which is used as a curing agent for tile grout, also needs to be monitored.

[0003] Currently, there is a lack of methods in China to accurately detect the content of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine in tile grout. Summary of the Invention

[0004] This application provides a method for detecting the content of diamine compounds in tile grout, which can simultaneously and accurately detect the content of multiple diamine compounds.

[0005] This application provides a method for detecting the content of diamine compounds in tile grout, comprising: obtaining standard solutions of diamine compounds at various concentrations; performing derivatization treatment on the standard solutions of diamine compounds at various concentrations to obtain standard solutions of diamine derivatives at various concentrations; testing the standard solutions of diamine derivatives at various concentrations in a chromatograph, wherein the standard solutions of diamine derivatives at various concentrations pass through a separation system containing a moderately polar stationary phase, and obtaining multiple chromatographic peaks corresponding to the standard solutions of diamine derivatives at various concentrations based on the concentration changes of the separated components; obtaining a scatter plot with the area of ​​the chromatographic peaks of the standard solutions of diamine derivatives at various concentrations as the ordinate and the concentration corresponding to the area of ​​the chromatographic peaks as the abscissa, and obtaining a standard working curve after fitting; and further testing the standard solutions of diamine derivatives at various concentrations in a chromatogram. The sample containing diamine compounds is mixed and diluted with a solvent to obtain a sample solution. The sample solution is then derivatized to obtain a derivatized sample solution. The derivatized sample solution is tested in a chromatograph. The derivatized sample solution passes through a separation system containing a moderately polar stationary phase. The area of ​​the diamine compound chromatographic peak is obtained based on the concentration change of the separated components. The concentration of the diamine compound in the derivatized sample solution is obtained by relating the peak area to the concentration corresponding to the standard working curve. The content of the diamine compound in the sample is then determined. The diamine compounds include 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine. The derivatization process involves converting the diamine compounds into diaminophenyl compounds.

[0006] In any embodiment of this application, the moderately polar stationary phase comprises (50% phenyl)-methylpolysiloxane.

[0007] In any embodiment of this application, in the steps of derivatizing standard solutions of diamine compounds of various concentrations and derivatizing the sample solution to be tested, the derivatizing reagent is independently selected from at least one of benzaldehyde and isobutyraldehyde.

[0008] In any embodiment of this application, in the step of derivatizing standard solutions of diamine compounds of various concentrations, the molar ratio of the derivatizing reagent to the standard solutions of diamine compounds of various concentrations is greater than 2:1, wherein the molar number of the derivatizing reagent is based on aldehyde groups, and the molar number of the standard solutions of diamine compounds of various concentrations is based on the amino groups contained therein.

[0009] In any embodiment of this application, in the step of derivatizing the sample solution to be tested, the molar ratio of the derivatizing reagent to the sample to be tested is greater than 2:1, wherein the number of moles of the derivatizing reagent is calculated in terms of aldehyde groups, and the number of moles of the sample to be tested is calculated in terms of the number of amine groups contained therein.

[0010] In any embodiment of this application, the temperature of the derivatization process is 30–50°C, and the time of the derivatization process is 20–40 min.

[0011] In any embodiment of this application, the temperature of the derivatization process is 30–50°C, and the time of the derivatization process is 20–40 min.

[0012] In any embodiment of this application, in the steps of testing standard solutions of diamine derivatives of various concentrations in a chromatograph and testing derivatized test sample solutions in a chromatograph, when passing through a separation system containing a moderately polar stationary phase, the separation system is first kept at 80–120°C for 0.5–1.5 min; then kept at 220–270°C for 0.5–1.5 min; and finally kept at 280–320°C for 3–5 min.

[0013] In any embodiment of this application, prior to the step of testing the derivatized test sample solution in a chromatograph, the method further includes filtering the derivatized test sample solution using at least one filter membrane selected from hydrophobic polytetrafluoroethylene, nylon 66, and polypropylene.

[0014] The method for detecting the content of diamine compounds in tile grout according to the embodiments of this application can use derivatization to convert diamine compounds into corresponding diaminophenyl compounds, thereby improving the sensitivity of chromatographic testing, making the chromatographic peaks sharp, and improving the accuracy of measurement; by establishing a standard curve and coupling it with gas chromatography-mass spectrometry, the content of multiple diamine compounds can be detected at one time, improving the detection efficiency; and impurities adsorbed on 1,3-cyclohexanedimethylamine standards and 1,3-cyclohexanedimethylamine derivatives can be removed by using a moderately polar stationary phase, thereby improving the accuracy of measurement. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is the chromatogram of the derivatized test sample solution in Example 1 of this application;

[0017] Figure 2 This is the chromatogram of the sample solution to be tested in Comparative Example 1 of this application;

[0018] Figure 3 The chromatogram of the diamine derivative standard solution in Comparative Example 2 of this application is shown.

[0019] Figure 4The chromatogram of the diamine derivative standard solution in Comparative Example 3 of this application is shown.

[0020] Figure 5 This is a chromatogram of the diamine derivative standard solution in Example 1 of this application. Detailed Implementation

[0021] To better understand the above-mentioned objectives, features, and advantages of this application, the solution of this application will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0022] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this application may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of this application, and not all embodiments.

[0023] The following detailed description, with appropriate reference to the accompanying drawings, discloses embodiments of the method for detecting the content of diamine compounds in tile grout according to this application. However, unnecessary details may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of essentially the same structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided for the purpose of enabling those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0024] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60–120 and 80–110 are listed for a specific parameter, it is understood that ranges of 60–110 and 80–120 are also expected. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1–3, 1–4, 1–5, 2–3, 2–4, and 2–5. In this application, unless otherwise stated, the numerical range "a–b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0~5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0025] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions, and such technical solutions shall be deemed to be included in the disclosure of this application.

[0026] Unless otherwise specified, all steps in this application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0027] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0028] Unless otherwise specified, this application uses conventional testing methods or testing methods recommended by the instrument.

[0029] Currently, there are no methods or standards for simultaneously detecting 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine. It is known that the primary method for detecting 1,6-hexanediamine content is the "GB 31604.43-2016 National Food Safety Standard for Food Contact Materials and Articles: Determination of Ethylenediamine and Hexanediamine Migration." This standard mainly targets food contact materials and articles, not the matrix of tile grout, and it does not include methods for detecting 1,3-cyclohexanedimethylamine and 1,3-propanediamine. Furthermore, ethyl chloroformate used in this standard is a highly toxic substance, difficult to obtain, and poses safety risks in its use and storage.

[0030] Furthermore, since diamine compounds contain two amine groups and have relatively high polarity, direct analysis using gas chromatography-mass spectrometry (GC-MS) can result in peak tailing and low sensitivity. Additionally, impurities in the sample can affect the calculation of chromatographic peak areas, thus impacting the accuracy of qualitative and quantitative analysis.

[0031] The applicant discovered that a special derivatization reagent can be used to convert diamine compounds into corresponding diaminophenyl compounds, avoiding the use of the highly toxic ethyl chloroformate. At the same time, it makes the chromatographic peaks sharp, improves the sensitivity of chromatographic tests, and also improves the accuracy of measurements.

[0032] The applicant also discovered that 1,3-cyclohexanedimethylamine in the tile grout binds to impurities, and that after derivatization of 1,3-cyclohexanedimethylamine, the 1,3-cyclohexanedimethylamine derivative binds to new impurities, affecting the accuracy of the detection. While polar chromatographic columns can separate impurities, only by selecting a moderately polar (50% phenyl)-methylpolysiloxane column can the separation of impurities be maximized, thereby improving the accuracy of the measurement.

[0033] The detection method proposed in this application can effectively fill the gap in the detection of diamine compounds in tile grout, and can effectively monitor the content of diamine compounds in raw materials and finished products, providing effective data to guide actual production.

[0034]

Detection Method

[0035] A method for detecting the content of diamine compounds in tile grout includes: S1. Obtaining standard solutions of diamine compounds at various concentrations; S2. Derivatizing the standard solutions of diamine compounds at various concentrations to obtain standard solutions of diamine derivatives at various concentrations; S3. Testing the standard solutions of diamine derivatives at various concentrations in a chromatograph, wherein the standard solutions of diamine derivatives at various concentrations pass through a separation system containing a moderately polar stationary phase, and multiple chromatographic peaks corresponding to the standard solutions of diamine derivatives at various concentrations are obtained based on the concentration changes of the separated components; S4. Obtaining a scatter plot with the area of ​​the chromatographic peaks of the standard solutions of diamine derivatives at various concentrations as the ordinate and the concentration corresponding to the area of ​​the chromatographic peak as the abscissa, and fitting the plot to obtain a standard working curve; S5. The sample containing diamine compounds is mixed and diluted with a solvent to obtain a sample solution; S6. The sample solution is derivatized to obtain a derivatized sample solution; S7. The derivatized sample solution is tested in a chromatograph. The derivatized sample solution passes through a separation system containing a moderately polar stationary phase. The area of ​​the diamine compound chromatographic peak is obtained based on the concentration change of the separated components. The concentration of the diamine compound in the derivatized sample solution is obtained by comparing the peak area with the concentration corresponding to the standard working curve, and then the content of the diamine compound in the sample is obtained. The diamine compounds include 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine. The derivatization process includes converting the diamine compounds into diaminophenyl compounds. In steps S1-S4, a standard working curve is plotted using the concentration of the diamine compound standard and the corresponding chromatographic peak area. Step S2 aims to convert the amino groups in the diamine compound standard into diaminophenyl compounds, thereby improving the chromatograph's sensitivity to the diamine compound standard and avoiding peak tailing caused by the high polarity of the amino groups. This improves the accuracy of peak area calculation and further enhances the accuracy of the standard curve. In steps S5-S7, the peak areas of the diamine compounds in the diluted sample are measured using the chromatograph, and the results are input into the standard curve to obtain the corresponding concentrations. The content of the diamine compounds in the undiluted sample is then calculated. The derivatization process in step S6 serves the same purpose as the derivatization process in step S2.

[0036] In one example, step S1 includes: mixing and diluting diamine compound standards with solvents to obtain diamine compound standard solutions of various concentrations. The solvent can be primary water, and the diamine compound standards are diluted to a set concentration to prepare a series of diamine compound standard solutions of various concentrations.

[0037] In some embodiments, in step S2, benzaldehyde can be used to derivatize the standard solution of diamine compounds, thereby converting the diamine compounds into diaminophenyl compounds.

[0038] In one example, in steps S1-S2, 0.2 g of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine standards are accurately weighed and diluted to 100 mL with primary water to prepare a standard solution with a concentration of 2000 mg / L. 60 μL, 150 μL, 300 μL, 600 μL, and 1500 μL of the standard solution are respectively pipetted into 50 mL Erlenmeyer flasks. 2.5 mL of ammonia (3%) is added, followed by 7.5 mL of sodium hydroxide solution (5 mol / L), then 1 mL of benzaldehyde, and then 9 mL of toluene. A magnetic stir bar is added, and the mixture is stirred in a water bath at 40 °C for 30 min. The mixture is then allowed to separate into layers. If separation does not occur, centrifugation at 10000 rpm for 5 min is performed.

[0039] In some embodiments, in step S3, a gas chromatography-mass spectrometry (GC-MS) instrument can be used to test a series of diamine derivative standard solutions of different concentrations, and the chromatographic peak areas corresponding to the diamine derivative standard solutions of different concentrations can be read to obtain multiple sets of concentration-chromatographic peak area data.

[0040] In some embodiments, in step S4, the multiple sets of concentration-chromatographic peak area data obtained in step S3 can be plotted with chromatographic peak area as the ordinate and concentration as the abscissa to obtain different points, and then a standard working curve can be obtained by fitting.

[0041] In some embodiments, in step S4, when testing the content of different types of diamine compounds, multiple standard working curves corresponding to different types of diamine compounds can be obtained. For example, when the diamine compound standard solution in S1 is 1,6-hexanediamine, the obtained standard working curve is that of 1,6-hexanediamine; when the diamine compound standard solution in S1 is 1,3-cyclohexanedimethylamine, the obtained standard working curve is that of 1,3-cyclohexanedimethylamine; and when the diamine compound standard solution in S1 is 1,3-propanediamine, the obtained standard working curve is that of 1,3-propanediamine.

[0042] In some embodiments, in step S5, the solvent is at least one of ammonia (3%), sodium hydroxide solution (5 mol / L), and toluene.

[0043] In some embodiments, in steps S5-S6, 1g of the sample to be tested can be weighed into a 50mL conical flask, 2.5mL of ammonia (3%) can be added, followed by 7.5mL of sodium hydroxide solution (5mol / L), 1mL of benzaldehyde, and 9mL of toluene. A magnetic stir bar can be added, and the mixture can be stirred in a water bath at 40℃ for 30min. The mixture can be allowed to stand and separate into layers. If the layers do not separate, the mixture can be centrifuged at 10000r / min for 5min. Finally, the upper layer is taken.

[0044] In some embodiments, in step S7, after performing chromatographic testing on the derivatized test sample solution, a chromatogram is obtained. Based on the peak positions on the chromatogram, different types of diamine compounds can be identified, namely 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine. The peak areas of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine are then calculated. Based on the standard working curves of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine, the concentrations of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine in the derivatized test sample solution are then determined. Finally, based on the dilution factor, the content of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine in the test sample is calculated.

[0045] In some embodiments, the moderately polar stationary phase comprises (50% phenyl)-methylpolysiloxane. This moderately polar stationary phase can effectively separate impurities adsorbed on 1,3-cyclohexanedimethylamine, improving the accuracy of measurements.

[0046] In some embodiments, in the steps of derivatizing standard solutions of diamine compounds of various concentrations and derivatizing the sample solution to be tested, the derivatizing reagent is independently selected from at least one of benzaldehyde and isobutyraldehyde. Benzaldehyde and isobutyraldehyde can safely and greenly convert amine groups into diamine compounds, resulting in sharp peak shapes in the chromatogram, improving the sensitivity of the chromatographic test, and also improving the accuracy of the measurement.

[0047] In some embodiments, in the step of derivatizing standard solutions of diamine compounds of various concentrations, the molar ratio of the derivatizing reagent to the standard solutions of diamine compounds of various concentrations is greater than 2:1, wherein the molar number of the derivatizing reagent is based on aldehyde groups, and the molar number of the standard solutions of diamine compounds of various concentrations is based on the amino groups they contain. Derivatizing reagents within this range can better convert amino groups to diaminophenyl groups.

[0048] In some embodiments, the content of hardener in the grout is up to 30%. Assuming that the hardener is entirely ethylenediamine, which has the smallest molecular weight, with a molar mass of 60 g / mol, based on the reaction between one molecule of a diamine compound and two molecules of benzaldehyde, the number of moles of benzaldehyde consumed is calculated as: 1 g × 30% × 2 / 60 g / mol = 0.01 mol. Given that the molar mass of benzaldehyde is 106 g / mol and the density of benzaldehyde is 1.044 g / mL, the volume of benzaldehyde consumed is: 0.01 mol × 106 g / mol / 1.044 g / mL = 1.02 mL. Therefore, the theoretical maximum amount of benzaldehyde that can be added is 1 mL.

[0049] In some embodiments, during the derivatization process of the test sample solution, the molar ratio of the derivatizing reagent to the test sample is greater than 2:1, wherein the molar number of the derivatizing reagent is based on aldehyde groups, and the molar number of the test sample is based on the number of amino groups it contains. Derivatizing reagents within this range can better convert amino groups to diaminophenyl groups.

[0050] In some embodiments, the temperature of the derivatization process in step S2 is 30–50°C, and the derivatization time is 20–40 min.

[0051] In some embodiments, the temperature of the derivatization process in step S2 is 40°C and the time of the derivatization process is 30 min.

[0052] In some embodiments, the temperature of the derivatization process in step S6 is 30–50°C, and the derivatization time is 20–40 min.

[0053] In some embodiments, the temperature of the derivatization process in step S6 is 40°C and the time of the derivatization process is 30 min.

[0054] In some embodiments, during the steps of testing standard solutions of diamine derivatives at various concentrations and testing derivatized sample solutions in a chromatograph, when passing through a separation system containing a moderately polar stationary phase, the separation system is first held at 80–120°C for 0.5–1.5 min; then at 220–270°C for 0.5–1.5 min; and finally at 280–320°C for 3–5 min. Specifically, after holding at 80–120°C for 0.5–1.5 min, the temperature is increased to 220–270°C at a rate of 20–40°C / min, held for 0.5–1.5 min, and then increased to 280–320°C at a rate of 5–20°C / min, held for 3–5 min. This temperature programming within this range effectively separates diamine compounds and other impurities in the standards and sample, thereby achieving accurate quantification.

[0055] In some embodiments, after steps S5-S6, the supernatant of the derivatized test sample solution is filtered with at least one of hydrophobic polytetrafluoroethylene, nylon 66, and polypropylene to remove impurities and improve measurement accuracy.

[0056] In some embodiments, the formulas for calculating the contents of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine are as follows:

[0057]

[0058] X—The content of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine and 1,3-propanediamine in the sample to be tested, in milligrams per kilogram (mg / kg);

[0059] C—The concentrations of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine read from the standard working curve, in milligrams per liter (mg / L);

[0060] V—Volume at a fixed volume, 10 mL;

[0061] F—Dilution factor;

[0062] m — Sample mass, in grams (g).

[0063] Example 1

[0064] S1. Accurately weigh 0.2 g of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine standards with a purity greater than 99%, and dilute to 100 mL with primary water to prepare a 2000 mg / L diamine standard solution. Pipette the volumes of the diamine standard solutions shown in Table 1 into 50 mL Erlenmeyer flasks to prepare diamine standard solutions of various concentrations.

[0065] S2. Add 2.5 mL of ammonia (3%) to an Erlenmeyer flask, then add 7.5 mL of sodium hydroxide solution (5 mol / L), then add 1 mL of benzaldehyde, then add 9 mL of toluene. Add a magnetic stir bar and stir in a 40°C water bath for 30 min. Let it stand to separate the layers. If it does not separate, centrifuge at 10000 r / min for 5 min to obtain the upper layer, which is the standard solution of diamine derivatives.

[0066] Table 1

[0067]

[0068] S3. The standard solution of the diamine derivative obtained in step S2 was subjected to chromatographic analysis using gas chromatography-mass spectrometry (GC-MS) to obtain chromatographic peaks, such as... Figure 5 As shown, the chromatographic test conditions are as follows:

[0069] Gas chromatography parameters: capillary column length 30m, inner diameter 0.25mm, film thickness 0.25μm; packing material (50% phenyl)methylpolysiloxane;

[0070] Inlet temperature: 300℃ using the temperature program shown in Table 3; Flow rate: 1 mL / min; Injection volume: 1 μL; Injection mode: split injection; Split ratio: 25:1; Transfer line temperature: 300℃; Ion source temperature: 300℃;

[0071] Mass spectrometry parameters: Acquisition mode: SIM; Solvent delay time: 4 min;

[0072] Collected ions: Featured selected ions are shown in Table 2 below:

[0073] Table 2

[0074] target Quantitative ions Qualitative ions 1,6-Hexamethylenediamine derivatives 186 187,174,118 1,3-Cyclohexanedimethylamine derivatives 213 118,170 1,3-Propanediamine derivatives 118 132,146

[0075] Table 3

[0076]

[0077] S4. Plot standard working curves with the peak areas of the chromatographic peaks of the 1,6-hexanediamine derivative, 1,3-cyclohexanedimethylamine derivative, and 1,3-propanediamine derivative as the ordinate and the concentrations of the standard solutions of the 1,6-hexanediamine derivative, 1,3-cyclohexanedimethylamine derivative, and 1,3-propanediamine derivative as the abscissa. The standard working curves are as follows:

[0078] 1,6-hexanediamine derivative: Y=37079.8X, R 2 =0.9979, X is in mg / L, and Y is in 1;

[0079] 1,3-Cyclohexanedimethylamine derivative: Y = 13875.8X, R 2 =0.9987, X is in mg / L, and Y is in 1;

[0080] 1,3-Propanediamine derivatives: Y = 36522.4X, R 2 =0.9974, where X is in mg / L and Y is in 1.

[0081] S5-S6. Weigh 1g of the sample to be tested into a 50mL Erlenmeyer flask, add 2.5mL of ammonia (3%), then add 7.5mL of sodium hydroxide solution (5mol / L), then add 1mL of benzaldehyde, then add 9mL of toluene, add a magnetic stir bar, stir in a 40℃ water bath for 30min, and let stand to separate the layers. If the layers do not separate, centrifuge at 10000r / min for 5min to obtain the supernatant, which is the derivatized sample solution.

[0082] S7. Transfer the derivatized sample solution to a syringe using a 1 mL syringe, filter it with hydrophobic PTFE, and then perform chromatographic analysis using gas chromatography-mass spectrometry (GC-MS). The chromatographic conditions are the same as in step S3, and the chromatogram is shown below. Figure 1 As shown, the peak areas of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine were 3446477, 2759343, and 3387999, respectively. Substituting these values ​​into the standard curve for 1,6-hexanediamine derivatives (Y = 37079.8X), its concentration was calculated to be 92.948 mg / L. Substituting these values ​​into the standard curve for 1,3-cyclohexanedimethylamine derivatives (Y = 13875.8X), its concentration was calculated to be 198.861 mg / L. Substituting these values ​​into the standard curve for 1,3-propanediamine derivatives (36522.4X), its concentration was calculated to be 92.765 mg / L. The contents of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine in the sample were then calculated using the following formulas: 881.7 mg / kg, 1886.4 mg / kg, and 880.0 mg / kg, respectively.

[0083]

[0084] X — The content of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine in the sample, in milligrams per kilogram (mg / kg);

[0085] C—The concentrations of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine read from the standard curve, in milligrams per liter (mg / L);

[0086] V—Volume at a fixed volume, 10 mL;

[0087] F—Dilution factor;

[0088] m — Sample mass, in grams (g).

[0089] Example 2

[0090] The experimental procedure is the same as in Example 1, except that benzaldehyde in steps S2 and S5-S6 is replaced with isobutyraldehyde.

[0091] Comparative Example 1

[0092] The experimental procedure is the same as in Example 1, except that benzaldehyde in steps S2 and S5-S6 is omitted. The resulting chromatogram is shown below. Figure 2 As shown. By Figure 2 It is known that 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine exhibit peak tailing and low sensitivity, making accurate quantification impossible.

[0093] Comparative Example 2

[0094] The experimental procedure is the same as in Example 1, except that the packing material (50%-phenyl)methylpolysiloxane used in steps S3 and S7 is replaced with (5%-phenyl)methylpolysiloxane. The resulting chromatogram is shown below. Figure 3 As shown. By Figure 3 The peak shapes of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine indicate that 1,3-cyclohexanedimethylamine is coated with impurities, making precise quantification impossible.

[0095] Comparative Example 3

[0096] The experimental procedure was the same as in Example 1, except that the packing material (50% phenyl)methylpolysiloxane used in steps S3 and S7 was replaced with highly polar polyethylene glycol. The resulting chromatogram is shown below. Figure 4 As shown. By Figure 4 The peak shapes of 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine indicate that 1,3-cyclohexanedimethylamine still contains impurities. The target peak and the impurity peak did not achieve baseline separation, making accurate quantification impossible.

[0097] The above description is merely a specific implementation of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the protection scope of this application.

Claims

1. A method for detecting the content of diamine compounds in tile grout, characterized in that, include: Obtain standard solutions of diamine compounds at various concentrations; The standard solutions of diamine compounds of various concentrations were subjected to derivatization treatment to obtain standard solutions of diamine derivatives of various concentrations. The derivatization reagent was selected from at least one of benzaldehyde and isobutyraldehyde. The molar ratio of the derivatization reagent to the standard solutions of diamine compounds of various concentrations was greater than 2:

1. The molar number of the derivatization reagent was calculated based on the aldehyde group. The molar number of the standard solutions of diamine compounds of various concentrations was calculated based on the amine group contained therein. The derivatization treatment temperature was 30~50 ℃ and the derivatization treatment time was 20~40 min. The standard solutions of the diamine derivatives at various concentrations were tested in a chromatograph. The standard solutions of the diamine derivatives at various concentrations were separated by a separation system containing a medium polarity stationary phase. Based on the concentration changes of the separated components, multiple chromatographic peaks corresponding to the standard solutions of the diamine derivatives at various concentrations were obtained. The medium polarity stationary phase included (50%-phenyl)-methylpolysiloxane. A scatter plot was obtained by using the area of ​​the chromatographic peaks of standard solutions of diamine derivatives at various concentrations as the ordinate and the concentration corresponding to the area of ​​the chromatographic peaks as the abscissa. After fitting, a standard working curve was obtained. The test sample containing the diamine compound is mixed and diluted with a solvent to obtain a test sample solution; The sample solution to be tested is derivatized to obtain a derivatized sample solution. The derivatizing reagent is selected from at least one of benzaldehyde and isobutyraldehyde. The molar ratio of the derivatizing reagent to the sample to be tested is greater than 2:

1. The number of moles of the derivatizing reagent is based on the aldehyde group, and the number of moles of the sample to be tested is based on the number of amine groups contained therein. The temperature of the derivatization treatment is 30~50 ℃, and the time of the derivatization treatment is 20~40 min. The derivatized test sample solution is tested in the chromatograph. The derivatized test sample solution passes through the separation system. The area of ​​the chromatographic peak of the diamine compound is obtained according to the concentration change of the separated components. The concentration of the diamine compound in the derivatized test sample solution is obtained by the relationship between the area and concentration of the chromatographic peak corresponding to the standard working curve. Then, the content of the diamine compound in the test sample is obtained. The diamine compounds include 1,6-hexanediamine, 1,3-cyclohexanedimethylamine, and 1,3-propanediamine. The derivatization process involves converting the diamine compounds into diaminophenyl compounds. The separation system is first kept at 80-120 °C for 0.5-1.5 min, then at 220-270 °C for 0.5-1.5 min, and finally at 280-320 °C for 3-5 min. The chromatograph uses SIM acquisition mode with a solvent delay time of 4 min. The qualitative ions for the 1,6-hexanediamine derivative are 187, 174, and 118, and the quantitative ion is 186. The qualitative ions for the 1,3-cyclohexanedimethylamine derivative are 118 and 170, and the quantitative ion is 213. The qualitative ions for the 1,3-propanediamine derivative are 132 and 146, and the quantitative ion is 118.

2. The detection method according to claim 1, characterized in that, The procedure prior to the step of testing the derivatized test sample solution in a chromatograph includes: The derivatized test sample solution was filtered using at least one filter membrane selected from hydrophobic polytetrafluoroethylene, nylon 66, and polypropylene.

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