Headspace-gas chromatography detection method for 1, 3-butadiene in automotive interior material

Abstract

The invention discloses a headspace-gas chromatography detection method for 1, 3-butadiene in an automotive interior material, which comprises the following steps: 1) crushing a sample into fine particles, freezing with liquid nitrogen, embrittling, and crushing at low temperature; and (2) weighing a sample which is recovered to room temperature after being crushed, putting the sample into a headspace bottle, quickly sealing, and carrying out gas chromatography detection in a headspace sampling mode. On the basis of the headspace-gas chromatography technology, by optimizing headspace sampling conditions, instrument parameters and chromatographic column selection, the 1, 3-butadiene detection method which is simple and convenient in pretreatment, high in sensitivity and accurate in quantification is established. And the method is precisely positioned on a specific and complex substrate, namely an automotive interior material. Compared with the prior art, the method is simple and convenient to operate and high in detection speed, can effectively avoid the problems of incomplete dissolution, difficulty in sample introduction and the like, is suitable for measuring an actual sample, and provides a reliable technical means for detecting the residual quantity of 1, 3-butadiene in the automotive interior material.

Description

Technical Field

[0001] This application relates to the field of compound detection technology, specifically to a headspace-gas chromatography method for the detection of 1,3-butadiene in automotive interior materials. Background Technology

[0002] 1,3-Butadiene is an important industrial chemical widely used in the synthesis of rubber and plastics, commonly found in polymers such as polybutadiene rubber, acrylonitrile-butadiene-styrene copolymer (ABS), and styrene-butadiene rubber (SBR) used in automotive interior materials. During material processing, some 1,3-butadiene monomers may be released through high-temperature degradation. During use, unreacted 1,3-butadiene monomers may remain in the finished product, slowly released into the confined space of a vehicle, posing a potential health risk through inhalation or skin contact. According to the 2017 list of carcinogens published by the International Agency for Research on Cancer (IARC) of the World Health Organization, 1,3-butadiene is classified as a Group 1 carcinogen, and long-term exposure is closely associated with blood disorders such as leukemia. Therefore, accurately determining the residual amount of 1,3-butadiene in automotive interior materials is crucial for protecting the health of passengers and improving in-vehicle air quality.

[0003] Currently, the detection of volatile organic compounds (VOCs) in vehicles mainly focuses on conventional items such as volatile organic compounds (VOCs) or aldehydes and ketones. However, a large amount of polymer materials containing ABS components, such as ABS and ABS+PC, are used in vehicle interiors. These products are prone to 1,3-butadiene residues, and specific or rapid detection methods for 1,3-butadiene, a highly toxic and carcinogenic substance, are still inadequate. Some existing detection standards borrow analytical methods from food contact materials, using headspace or liquid chromatography injection after solvent dissolution for analysis. However, automotive interior materials have complex compositions, often containing large amounts of fillers, plasticizers, flame retardants, and cross-linking structures. The injection conditions and instrument conditions used in traditional methods are insufficient to completely dissolve the samples, resulting in incomplete release of the target analyte and low recovery rates.

[0004] Furthermore, automotive interior materials have complex compositions, and the volatile organic compounds released during pyrolysis are diverse, including acrylonitrile, ethylbenzene, styrene, isoprene, n-hexane, and many other interfering substances. Traditional chromatographic columns are less effective at separating these compounds with similar boiling points, easily leading to co-elution or peak overlap of 1,3-butadiene with adjacent peaks, affecting both qualitative and quantitative accuracy.

[0005] Currently, there are no specific standard methods, either domestically or internationally, for the detection of 1,3-butadiene in automotive interior plastics. my country's national standard, GB 31604.12-2016 "National Food Safety Standard for Food Contact Materials and Articles - Determination of 1,3-Butadiene and Determination of Migration," specifies the testing methods for 1,3-butadiene in food contact materials and articles. However, directly applying this standard to the detection of highly volatile and extremely low-content 1,3-butadiene in automotive interior plastics presents problems such as insufficient sensitivity, severe matrix interference, and poor quantitative accuracy. Furthermore, the detection of 1,3-butadiene in the aforementioned national standard requires specialized chromatographic columns and detection procedures, resulting in poor versatility and high testing costs. Summary of the Invention

[0006] In view of this, the main objective of this invention is to establish a headspace-gas chromatography method for the detection of 1,3-butadiene in automotive interior materials, so as to achieve efficient and reliable determination of the residual amount of 1,3-butadiene in automotive interior materials.

[0007] To achieve the above-mentioned objectives, this application provides a headspace-gas chromatography method for the detection of 1,3-butadiene in automotive interior materials, comprising the following steps:

[0008] 1) The sample was crushed into fine particles, frozen and embrittled with liquid nitrogen, and then pulverized at low temperature; 2) Weigh the pulverized sample, which has been brought to room temperature, into a headspace vial, seal it quickly, and perform gas chromatography detection via headspace injection. The headspace injection conditions include: a) Balancing time: 15-60 min; b) Headspace heating temperature: 70-95°C; c) Pressurization pressure: 80 kPa (11.6 psi) - 150 kPa (21.8 psi); d) Pressurization time: 0.5 min - 5.0 min; e) Injection time: 0.02 min (1.2 s) - 0.1 min (6 s); f) Needle removal time: 0.02 min (1.2 s) - 0.15 min (6 s); g) GC analysis cycle time: 25 min - 50 min; h) Transmission line temperature: 80 °C - 110 °C; i) Sampling needle temperature: 80 °C - 110 °C; j) Carrier gas: 20.0 psi (138 kPa) - 35.0 psi (241 kPa); Gas chromatography conditions include: a) Chromatographic column: HP-INNOWax Polyethylene Glycol or equivalent polar chromatographic column, column length 30 m, inner diameter 250 μm, film thickness 0.25 μm; b) Column temperature program: 80-85 °C for 10-12 min, increase to 120-125 °C at 8-10 °C / min and hold for 10-12 min; c) Inlet temperature: 220 °C; d) Detector temperature: 250 °C; e) Carrier nitrogen flow rate: 60-65 mL / min; f) Hydrogen flow rate: 40 mL / min; g) Airflow rate: 400 mL / min; h) Tail gas flow rate: 100-105 kPa; i) Detector: Flame ionization detector (FID), with the detector temperature set at 250 °C.

[0009] Furthermore, in step 1), liquid nitrogen is continuously added during the pulverization process to ensure that the pulverization is carried out at a low temperature.

[0010] Furthermore, in step 1), the particle size of the pulverized sample is less than 1 mm.

[0011] Furthermore, in step 2), before sealing, a solvent for dissolving the sample is added to the headspace vial.

[0012] Furthermore, in step 2), after sealing, the internal standard solution is injected into the headspace vial for use as a blank control experiment.

[0013] Furthermore, in step 2), the headspace injection conditions include: a) Balancing time: 30 min; b) Furnace temperature: 80 °C; c) Pressure: 100 kPa (14.5 psi); d) Pressurization time: 2 min; e) Injection time: 0.04 min; f) Needle removal time: 0.1 min; g) GC analysis cycle time: 35 min; h) Transmission line temperature: 85 °C; i) Sampling needle temperature: 85 °C; j) Carrier gas: 25.0 psi.

[0014] Furthermore, the detection method also includes step 3): qualitative analysis based on the retention time of the standard substance, and quantitative analysis based on the plotted standard curve.

[0015] Furthermore, the qualitative analysis includes: quantifying 1,3-butadiene based on its retention time using an FID detector using peak area; when using an internal standard method, n-pentane, 1,4-difluorobenzene, or D6-benzene are selected as internal standards, and the retention time and response signal of the internal standard are used to perform relative quantitative correction of 1,3-butadiene.

[0016] Furthermore, the preparation of the standard curve includes: taking a certain amount of 1,3-butadiene standard and internal standard, dissolving and adjusting the volume with a solvent to prepare a series of standard working solutions containing a fixed concentration of internal standard, and preparing 1,3-butadiene into a series of concentrations; and, in combination with headspace sampling, placing each standard working solution in a headspace vial, heating it to equilibrium under the set equilibrium temperature and time conditions, and then extracting the gas on the liquid surface for gas chromatography analysis; recording the chromatographic peak areas of 1,3-butadiene and internal standard at each concentration, and plotting the internal standard calibration curve with the content of 1,3-butadiene as the abscissa and the ratio of the peak area of ​​1,3-butadiene to the peak area of ​​internal standard as the ordinate.

[0017] Furthermore, the concentrations of the 1,3-butadiene are 0.2 μg, 0.4 μg, 0.6 μg, 0.8 μg and 1.0 μg, respectively.

[0018] Compared with the prior art, the present invention has the following advantages: Currently, methods for detecting 1,3-butadiene in complex matrices of automotive interior materials are inadequate, with existing technologies suffering from cumbersome pretreatment, insufficient sensitivity, and inaccurate quantification. This invention, based on headspace gas chromatography (HGC), establishes a simple, highly sensitive, and quantitatively accurate method for detecting 1,3-butadiene by optimizing headspace injection conditions, instrument parameters, and column selection. Furthermore, the method is precisely targeted at the specific and complex matrix of "automotive interior materials," providing a complete solution and addressing industry pain points. Compared to existing methods, this invention is simpler to operate, faster in detection, and effectively avoids problems such as incomplete dissolution and difficult injection, making it suitable for the determination of real samples and providing a reliable technical means for the detection of 1,3-butadiene residues in automotive interior materials.

[0019] Other features and advantages of this application will be described in detail in the following specific embodiments. Attached Figure Description

[0020] Figure 1 The chromatograms are for 1,3-butadiene, n-pentane, and N,N-dimethylformamide standards. The peak times for n-pentane, 1,3-butadiene, and N,N-dimethylformamide are 1.7 min, 2.1 min, and 9.3 min, respectively. Detailed Implementation

[0021] The present application will be further described below with reference to the embodiments. However, the present application is not limited to the listed embodiments, but should also include equivalent improvements and modifications of the technical solutions defined in the appended claims.

[0022] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0023] To address the shortcomings of existing food material testing standards when directly applied to the detection of 1,3-butadiene, a highly volatile compound present in very low concentrations in automotive interior plastics, such as insufficient sensitivity, severe matrix interference, and poor quantitative accuracy, this application provides a headspace-gas chromatography method for the detection of 1,3-butadiene. This method is applicable to complex automotive interior material matrices, features simple pretreatment, high sensitivity, and accurate quantitative analysis, and includes the following steps: 1) The sample was crushed into fine particles, frozen and embrittled with liquid nitrogen, and then pulverized at low temperature; 2) Weigh the pulverized sample, which has been brought to room temperature, into a headspace vial, seal it quickly, and perform gas chromatography detection via headspace injection. The headspace injection conditions include: a) Balancing time: 15-60 min; b) Headspace heating temperature: 70-95°C; c) Pressurization pressure: 80 kPa (11.6 psi) - 150 kPa (21.8 psi); d) Pressurization time: 0.5 min - 5.0 min; e) Injection time: 0.02 min (1.2 s) - 0.1 min (6 s); f) Needle removal time: 0.02 min (1.2 s) - 0.15 min (6 s); g) GC analysis cycle time: 25 min - 50 min; h) Transmission line temperature: 80 °C - 110 °C; i) Sampling needle temperature: 80 °C - 110 °C; j) Carrier gas: 20.0 psi (138 kPa) - 35.0 psi (241 kPa); Gas chromatography conditions include: a) Chromatographic column: HP-INNOWax Polyethylene Glycol or equivalent polar chromatographic column, column length 30 m, inner diameter 250 μm, film thickness 0.25 μm; b) Column temperature program: 80-85 °C for 10-12 min, increase to 120-125 °C at 8-10 °C / min and hold for 10-12 min; c) Inlet temperature: 220 °C; d) Detector temperature: 250 °C; e) Carrier nitrogen flow rate: 60-65 mL / min; f) Hydrogen flow rate: 40 mL / min; g) Airflow rate: 400 mL / min; h) Tail gas flow rate: 100-105 kPa; i) Detector: Flame ionization detector (FID), with the detector temperature set at 250 °C.

[0024] This invention pre-treats the sample in step 1), breaking it up and then subjecting it to liquid nitrogen cryocatalysis before pulverizing it using a grinder. This ensures that the material composition remains unchanged and that the pulverization is uniform and consistent, greatly improving the accuracy of the results. The method of breaking up the sample is not limited in this invention.

[0025] In some specific implementations, in step 1), liquid nitrogen is continuously added during the pulverization process to ensure that the pulverization is carried out at a low temperature. This process can be carried out in a pulverizer.

[0026] In some specific implementations, in step 1), the particle size of the crushed sample is less than 1 mm, for example, 0.8 mm, 0.6 mm, etc., less than 1 mm is acceptable.

[0027] In some specific embodiments, in step 2), before sealing, a solvent for dissolving the sample is added to the headspace vial, such as, but not limited to, N,N-dimethylformamide; the present invention dissolves the sample in a suitable solvent, places it in a headspace vial and heats it until gas-liquid equilibrium is reached, and then extracts the top gas for chromatographic analysis.

[0028] In some specific embodiments, after sealing, step 2) further includes injecting an internal standard solution into the headspace vial for blank control experiments; after injection, the sample can be thoroughly shaken to completely dissolve or uniformly disperse, and then left to stand for testing.

[0029] This invention performs sample analysis using the chromatographic conditions described in step 2): Preferably, in step 2), the headspace injection conditions include: a) Balancing time: Shortening the time may result in insufficient balancing, while extending the time can ensure complete balancing. 30 minutes is preferred. b) Headspace heating temperature: Too low a temperature may lead to incomplete volatilization, while too high a temperature may cause sample decomposition or side reactions; 80 °C is preferred. c) Pressure: The injection can still be completed by appropriately reducing the pressure, while increasing the pressure can increase the amount of sample entering the gas chromatograph; 100 kPa (14.5 psi) is preferred. d) Pressurization time: Short time may result in unstable pressure, while long time will reduce efficiency; 2 minutes is preferred. e) Injection time: Fine-tuning the injection time can control the volume of sample entering the chromatographic column, preferably 0.04 min; f) Needle withdrawal time: Fine-tuning the needle withdrawal time can control the sample volume entering the chromatographic column, preferably 0.1 min; g) GC analysis cycle time: Based on the optimized time of the specific chromatographic method, taking into account the needs of rapid GC and higher resolution, 35 min is preferred; h) Transmission line temperature: preferably 85 °C; i) Sampling needle temperature: The temperature of the transfer line and sampling needle is usually set slightly higher than the furnace temperature (e.g., 85°C) to prevent the sample from condensing during transfer, preferably 85°C; j) Carrier gas: The carrier gas pressure directly affects the linear velocity and separation effect, and 25.0 psi is preferred.

[0030] In step 2) of this invention, the headspace sampling conditions have been optimized compared to existing technologies, with improvements made to parameters such as pressurization pressure, needle removal time, and carrier gas, resulting in good detection accuracy and efficiency.

[0031] In step 2) of this invention, the gas chromatography conditions, including the carrier gas nitrogen flow rate, hydrogen flow rate, and air flow rate, were optimized. For example, increasing the hydrogen flow rate can improve the ignition efficiency of the hydrogen ion flame detector (FID) and thus increase detection efficiency. Furthermore, the chromatographic column commonly used in the prior art is a polystyrene-divinylbenzene quartz capillary column, 30 m long, 0.32 mm inner diameter, and 10 μm film thickness. This application, however, employs a chromatographic column specifically for the detection of automotive interior materials, as described above.

[0032] In this invention, the detection method further includes step 3): qualitative analysis based on the retention time of the standard substance, and quantitative analysis based on the plotted standard curve.

[0033] In some specific embodiments, the qualitative analysis includes: quantifying 1,3-butadiene by peak area under an FID detector based on the retention time of 1,3-butadiene; when using the internal standard method, n-pentane, 1,4-difluorobenzene, or D6-benzene are selected as internal standards, and the retention time and response signal of the internal standard are used to perform relative quantitative correction of 1,3-butadiene.

[0034] In some specific implementations, the construction of the standard curve includes: taking a certain amount of 1,3-butadiene standard and internal standard, dissolving and adjusting the volume with a solvent to prepare a series of standard working solutions containing a fixed concentration of internal standard, and preparing 1,3-butadiene into a series of concentrations; and, in combination with headspace sampling, placing each standard working solution in a headspace vial, heating it to equilibrium under set equilibrium temperature and time conditions, extracting the gas above the liquid for gas chromatography analysis; recording the chromatographic peak areas of 1,3-butadiene and internal standard at each concentration, and plotting the internal standard calibration curve with the content of 1,3-butadiene as the abscissa and the ratio of the peak area of ​​1,3-butadiene to the peak area of ​​internal standard as the ordinate.

[0035] In some specific embodiments, the concentrations of the 1,3-butadiene are 0.2 μg, 0.4 μg, 0.6 μg, 0.8 μg and 1.0 μg, respectively.

[0036] The following examples illustrate the headspace-gas chromatography method for detecting 1,3-butadiene in automotive interior materials provided in this application.

[0037] Unless otherwise specified, all raw materials involved in the embodiments of this application can be obtained from commercially available channels.

[0038] The instrument specifications are as follows: Agilent 6890N gas chromatograph, PE turbomatrix 110 headspace sampler or Agilent G1888 or other compatible models.

[0039] Example 1 (1) Sample pretreatment: Sample preparation: The sample was cut into small particles, frozen and embrittled in liquid nitrogen (about 10 minutes), and then pulverized in a grinder. Liquid nitrogen was continuously added during the pulverization process to ensure that the pulverization was carried out at a low temperature. The particle size of the pulverized sample was less than 1 mm. Weighing: After the pulverized sample returned to room temperature, 0.5 g of sample (accurate to 0.1 mg) was weighed using a balance and placed in a headspace vial. 5.0 mL of N,N-dimethylformamide was added as a solvent, and the vial was immediately capped and sealed. Subsequently, 100 μL of n-pentane standard solution was injected into the vial as an internal standard using a microsyringe. The sample was shaken thoroughly to completely dissolve or uniformly disperse it. The vial was allowed to stand for testing, and a blank control experiment was performed at the same time.

[0040] (2) Set the headspace sampler conditions and chromatographic conditions. Typical conditions are as follows: The headspace sampler conditions are listed below: a) Balancing time: 30 min; b) Furnace temperature: 80 °C; c) Pressure: 100 kPa (14.5 psi); d) Pressurization time: 2 min; e) Injection time: 0.04 min; f) Needle removal time: 0.1 min; g) GC analysis cycle time: 35 min; h) Transmission line temperature: 85 °C; i) Sampling needle temperature: 85 °C; j) Carrier gas: 25.0 psi.

[0041] The gas chromatography conditions are listed below: a) Column: Agilent 19091N-133 260 °C (maximum temperature) HP-TNNOWax Polyethylene Glycol, column length 30 m, inner diameter 250 μm, film thickness 0.25 μm; b) Column temperature program: 80 °C for 12 min, increase to 120 °C at 10 °C / min and hold for 10 min; c) Inlet temperature: 220 °C; d) Detector temperature: 250 °C; e) Carrier nitrogen flow rate: 65 mL / min; f) Hydrogen flow rate: 40 mL / min; g) Airflow rate: 400 mL / min; h) Tail-blown air flow rate: 100 kPa.

[0042] i) Detector: Flame ionization detector (FID), with the detector temperature set at 250 °C.

[0043] (3) Qualitative and quantitative selection: The retention time of 1,3-butadiene was approximately 2.1 min, and quantification was performed using peak area under an FID detector. When using the internal standard method, n-pentane was selected as the internal standard, and its retention time and response signal were used to correct the relative quantification of 1,3-butadiene.

[0044] (4) Plotting the standard curve: A certain amount of 1,3-butadiene and n-pentane standards were dissolved and diluted with N,N-dimethylformamide to prepare a series of standard working solutions containing a fixed concentration of n-pentane (100 μg) as an internal standard. The concentrations of 1,3-butadiene were 0.2 μg, 0.4 μg, 0.6 μg, 0.8 μg, and 1.0 μg, respectively. The gas chromatograph was adjusted to its optimal operating state, and headspace injection was used. Each standard working solution was placed in a headspace vial, heated to equilibrium under the set temperature and time conditions, and then the gas from the liquid was extracted and injected into the gas chromatograph for analysis. The peak areas of 1,3-butadiene and n-pentane at each concentration were recorded. An internal standard calibration curve was plotted with the 1,3-butadiene content (μg) on ​​the x-axis and the ratio of its peak area to that of n-pentane on the y-axis. Table 1 illustrates the linear regression of 1,3-butadiene.

[0045] Table 1

[0046] (5) Sample testing: The sample was processed according to the method in (1), analyzed using the chromatographic conditions described in (2), qualitative analysis was performed based on the retention times of the standard substances in (3) and (4), and quantitative analysis was performed in conjunction with the drawn standard curve.

[0047] In this embodiment, the sample was heated in the headspace and then measured under the chromatographic conditions described in step (2). The results are shown in Table 2.

[0048] Six parallel determinations were performed, and the average content of 1,3-butadiene in the sample was calculated to be 0.38 mg / kg, with a relative standard deviation (RSD) of 5.2%. Spiking recovery experiments were conducted, and the average recoveries ranged from 92.5% to 105.3% at three levels: 0.1, 0.5, and 1.0 mg / kg, demonstrating the accuracy and reliability of the method.

[0049] Table 2

[0050] Example 2 Similar to the steps in Example 1, the headspace sampler conditions are as follows: a) Equilibrium time: 40 min; b) Furnace temperature: 75 °C; c) Pressure: 120 kPa (17.4 psi); d) Pressurization time: 1.5 min; e) Injection time: 0.05 min; f) Needle removal time: 0.15 min; g) GC analysis cycle time: 40 min; h) Transmission line temperature: 90 °C; i) Sampling needle temperature: 90 °C; j) Carrier gas: 22.0 psi.

[0051] The gas chromatography conditions are as follows: a) Column: Agilent 19091N-133 (260 °C) HP-INNOWax Polyethylene Glycol, column length 30 m, inner diameter 250 μm, film thickness 0.25 μm; b) Column temperature program: 85 °C for 10 min, then increase to 125 °C at 8 °C / min and hold for 12 min; c) Inlet temperature: 220 °C; d) Detector temperature: 250 °C; e) Carrier gas (nitrogen) flow rate: 60 mL / min; f) Hydrogen flow rate: 40 mL / min; g) Airflow rate: 400 mL / min; h) Outlet gas flow rate: 105 kPa; i) Detector: Flame Ionization Detector (FID).

[0052] All the above parameter adjustments were within the allowable fluctuation range for conventional method development, and were able to maintain the quantitative accuracy, chromatographic peak resolution and detection sensitivity of 1,3-butadiene at the same level as in Example 1, meeting the requirements of the standard method.

[0053] At room temperature, a black PC+ABS plastic sample was shredded into fine particles, frozen in liquid nitrogen for about 10 minutes, and then pulverized in a grinder. Liquid nitrogen was continuously added during the pulverization process to ensure that the pulverization was carried out at a low temperature. After the pulverized half-product was restored to room temperature, 0.5 g of the above sample (accurate to 0.1 mg) was weighed using a balance, placed in a headspace vial, and 5.0 mL of N,N-dimethylformamide was added as a solvent. The vial was quickly sealed, heated in the headspace, and then measured. The results are shown in Table 3.

[0054] Six parallel determinations were performed, and the average content of 1,3-butadiene in the sample was calculated to be 0.26 mg / kg, with a relative standard deviation (RSD) of 4.8%. Spiking recovery experiments were conducted, and the average recoveries ranged from 91.2% to 108.6% at three levels: 0.1, 0.5, and 1.0 mg / kg, demonstrating the accuracy and reliability of the method.

[0055] Table 3

[0056] Following the method described in the embodiments of the present invention, multiple parallel determinations of 1,3-butadiene in different types of automotive interior materials were performed, and the results were relatively consistent, indicating that the method has good repeatability and high precision. Furthermore, the method has a detection limit of approximately 0.3 mg / kg, exhibiting high sensitivity, and is suitable for the accurate determination of trace amounts of 1,3-butadiene in automotive interior materials.

[0057] In summary, the embodiments of the present invention, based on headspace-gas chromatography, achieve efficient and reliable determination of 1,3-butadiene residues in automotive interior materials by optimizing headspace injection conditions, instrument parameters, and selecting commonly used chromatographic columns for automotive interior material detection. This invention features simple operation, accurate quantification, fast detection speed, and low cost, providing strong technical support for in-vehicle air quality control and material safety assessment.

[0058] Obviously, the above embodiments of this application are merely examples for clearly illustrating this application, and are not intended to limit the implementation of this application. Those skilled in the art can make other variations or modifications based on the above description. It is impossible to exhaustively list all possible implementations here. All obvious variations or modifications derived from the technical solutions of this application are within the scope of the spirit and scope of this application.

Claims

1. A headspace-gas chromatography method for the detection of 1,3-butadiene in automotive interior materials, characterized in that, Includes the following steps: 1) The sample was crushed into fine particles, frozen and embrittled with liquid nitrogen, and then pulverized at low temperature; 2) Weigh the pulverized sample, which has been brought to room temperature, into a headspace vial, seal it quickly, and perform gas chromatography detection via headspace injection. The headspace injection conditions include: a) Balancing time: 15-60 min; b) Headspace heating temperature: 70-95°C; c) Pressurization pressure: 80 kPa - 150 kPa; d) Pressurization time: 0.5 min - 5.0 min; e) Injection time: 0.02 min - 0.1 min; f) Needle removal time: 0.02 min - 0.15 min; g) GC analysis cycle time: 25 min - 50 min; h) Transmission line temperature: 80 °C - 110 °C; i) Sampling needle temperature: 80 °C - 110 °C; j) Carrier gas: 20.0 psi - 35.0 psi; Gas chromatography conditions include: a) Chromatographic column: HP-INNOWax Polyethylene Glycol or equivalent polar chromatographic column, column length 30 m, inner diameter 250 μm, film thickness 0.25 μm; b) Column temperature program: 80-85 °C for 10-12 min, increase to 120-125 °C at 8-10 °C / min and hold for 10-12 min; c) Inlet temperature: 220 °C; d) Detector temperature: 250 °C; e) Carrier nitrogen flow rate: 60-65 mL / min; f) Hydrogen flow rate: 40 mL / min; g) Airflow rate: 400 mL / min; h) Tail gas flow rate: 100-105 kPa; i) Detector: Hydrogen flame ionization detector, with the detector temperature set at 250 °C.

2. The headspace-gas chromatography detection method for 1,3-butadiene according to claim 1, characterized in that, In step 1), liquid nitrogen is continuously added during the pulverization process to ensure that the pulverization is carried out at a low temperature.

3. The headspace-gas chromatography detection method for 1,3-butadiene according to claim 1 or 2, characterized in that, In step 1), the particle size of the crushed sample is less than 1 mm.

4. The headspace-gas chromatography detection method for 1,3-butadiene according to claim 1, characterized in that, In step 2), before sealing, a solvent for dissolving the sample is added to the headspace vial.

5. The headspace-gas chromatography detection method for 1,3-butadiene according to claim 1, characterized in that, In step 2), after sealing, the internal standard solution is injected into the headspace vial for use as a blank control experiment.

6. The headspace-gas chromatography method for detecting 1,3-butadiene according to any one of claims 1-5, characterized in that, In step 2), the headspace injection conditions include: a) Balancing time: 30 min; b) Furnace temperature: 80 °C; c) Pressure: 100 kPa; d) Pressurization time: 2 min; e) Injection time: 0.04 min; f) Needle removal time: 0.1 min; g) GC analysis cycle time: 35 min; h) Transmission line temperature: 85 °C; i) Sampling needle temperature: 85 °C; j) Carrier gas: 25.0 psi.

7. The headspace-gas chromatography method for detecting 1,3-butadiene according to any one of claims 1-6, characterized in that, The detection method also includes step 3): qualitative analysis based on the retention time of the standard substance, and quantitative analysis based on the plotted standard curve.

8. The headspace-gas chromatography detection method for 1,3-butadiene according to claim 7, characterized in that, The qualitative analysis includes: quantifying 1,3-butadiene based on its retention time using a flame ionization detector (FID) with peak area; and when using an internal standard method, selecting n-pentane, 1,4-difluorobenzene, or D6-benzene as internal standards, and using the retention time and response signal of the internal standards to perform relative quantitative correction of 1,3-butadiene.

9. The headspace-gas chromatography detection method for 1,3-butadiene according to claim 7 or 8, characterized in that, The standard curve is prepared by: taking a certain amount of 1,3-butadiene standard and internal standard, dissolving them in a solvent and making up to volume to prepare a series of standard working solutions containing a fixed concentration of internal standard; preparing 1,3-butadiene into a series of concentrations; and, using headspace sampling, placing each standard working solution in a headspace vial, heating it to equilibrium under the set equilibrium temperature and time conditions, and then extracting the gas on the liquid surface for gas chromatography analysis; recording the chromatographic peak areas of 1,3-butadiene and internal standard at each concentration, and plotting the internal standard calibration curve with the content of 1,3-butadiene as the abscissa and the ratio of the peak area of ​​1,3-butadiene to the peak area of ​​internal standard as the ordinate.

10. The headspace-gas chromatography detection method for 1,3-butadiene according to claim 9, characterized in that, The concentrations of the 1,3-butadiene were 0.2 μg, 0.4 μg, 0.6 μg, 0.8 μg and 1.0 μg, respectively.

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