Determination method of (methyl) acrylate compounds in textiles

Abstract

The invention discloses a method for determining a (methyl) acrylate compound in a textile, which comprises the following steps: (1) placing an accurately weighed textile sample to be detected in a reactor, and adding an extracting agent for ultrasonic extraction to obtain an extract liquor; and (2) injecting the extract into a gas chromatograph-mass spectrometer, measuring the (methyl) acrylate compound and the peak area of the (methyl) acrylate compound, and calculating according to a standard curve equation to obtain the content of the (methyl) acrylate compound in the to-be-measured textile sample. According to the method, 12 (methyl) acrylate compounds in the textile can be accurately detected at the same time by adopting the ultrasonic extraction-gas chromatography-mass spectrometry method; the method is simple to operate, the detection process is easy to realize automation, the sensitivity is high, in the concentration range of 0.50-10.00 mg / L, the linear correlation coefficient reaches more than 0.998, the detection limit range is 0.09-2.41 mg / kg, the quantification limit is 0.32-7.44 mg / kg, the standard recovery rate is 87.71-99.43%, the relative standard deviation (RSD) is 1.07-2.81%, and the method has better accuracy and reproducibility.

Description

Technical Field

[0001] The invention belongs to the field of detection technology, and in particular relates to a method for determining (meth)acrylate compounds in textiles. Background Art

[0002] (Meth)acrylate compounds are widely used in textile processing, for example, as crosslinking agents, coating monomers or functional modifiers, and are mostly in the form of polymers. During polymerization, liquid substances are mainly converted into solid or gel states through covalent or ionic crosslinking (in-situ polymerization). In this process, non-polymerized monomers that have not been fully reacted may remain in the polymer, also known as residual monomers. Generally, existing technologies cannot achieve 100% complete polymerization under ideal conditions. Although the polymer itself is harmless, the (meth)acrylates remaining in the polymer are harmful, which not only greatly reduces the quality of the product, but also pollutes the environment and harms human health.

[0003] Most (meth)acrylates have low boiling points, are volatile, have strong pungent odors and are toxic, and even have reproductive toxicity. A small amount of residue will produce a strong odor, reduce air quality, and cause harm to human health. Experiments have shown that when mice inhale only 109g / m 3 Methyl acrylate is poisonous, and inhalation for 17 minutes will cause embryotoxicity (6-15 days of pregnancy), leading to muscle and bone structure disorders. Currently, ethyl acrylate (EA) is classified as a Group 2B carcinogen by the International Agency for Research on Cancer (IARC). Miller et al. used SD rats as research subjects and conducted animal experiments. The study found that inhalation of EA can induce thyroid endocrine disorders, stimulate pituitary TS secretion, and thus stimulate thyroid tumors (follicular adenoma and follicular adenocarcinoma).

[0004] On January 1, 2009, the EU REACH regulation officially entered the full registration stage. According to the requirements of the REACH regulation, polymer products exported from China to the EU are subject to monomer and additive registration, and declaration and authorization of substances of high concern. Therefore, it is necessary to establish a detection method for (meth) acrylate residues in textiles as soon as possible to ensure the safe use of related products, respond to the EU REACH regulation in a timely and effective manner, and promote the sustained growth of my country's textile-related export trade products.

[0005] my country's standard GB 9685-2016 "Standard for the Use of Additives in Food Contact Materials and Articles" clearly stipulates the production amount of (meth)acrylates and the maximum residual amount in packaging materials: in food packaging materials, the residual amount of (meth)acrylates shall not exceed 6 mg / kg. At present, the World Health Organization (WHO) International Agency for Research on Cancer has included some acrylates in the list of carcinogens, such as acrylic acid, methyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate, etc.

[0006] In textiles, the residues of (meth)acrylates can cause skin allergies, nausea, fatigue, carcinogenicity and other symptoms. The Blue Label Certification BSSL Consumer Safety Limit Substance List (v13.0) gives the restriction requirements and corresponding safety limits of (meth)acrylate substances in textiles, as shown in Table 1:

[0007] Table 1 BSSL Consumer Safety Limits Acrylate Limit List

[0008]

[0009] Note: A is textile products for infants and young children; B is textile products that come into direct contact with the skin; C is textile products that do not come into direct contact with the skin.

[0010] In summary, there is an urgent need to develop an efficient, accurate and simple method for the determination of (meth)acrylate residues in textiles to meet the increasingly stringent requirements for textile quality and safety testing. Summary of the invention

[0011] The purpose of the present invention is to address the above-mentioned problems in the prior art and to explore the determination method of the 12 (meth) acrylates included in BSSL using gas chromatography-mass spectrometry (GC-MS) technology. The pretreatment method is determined experimentally, and the optimal instrument analysis conditions are explored. Under the optimal detection conditions, method verification experiments such as linear correlation, detection limit, precision, etc. and actual sample detection are carried out, and finally an accurate and efficient determination method of (meth) acrylate compounds in textiles is obtained.

[0012] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0013] A method for determining (meth)acrylate compounds in textiles comprises the following steps:

[0014] (1) placing an accurately weighed textile sample to be tested in a reactor, adding an extractant for ultrasonic extraction, and obtaining an extract;

[0015] (2) Injecting the above extract into a gas chromatography-mass spectrometer to determine the (meth)acrylate compounds and their peak areas, and calculating the content of the (meth)acrylate compounds in the textile sample to be tested according to the standard curve equation.

[0016] The present invention is further configured such that the (meth)acrylate compounds include methyl acrylate, ethyl acrylate, butyl acrylate, tert-butyl acrylate, octadecyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, 2-ethylhexyl acrylate, 2-phenoxyethyl acrylate and 2-methoxyethyl acrylic acid.

[0017] The present invention is further configured such that, in step (1), the extractant is ethyl acetate.

[0018] The present invention is further configured such that, in step (1), the mass volume ratio of the textile sample to be tested and the extractant is 1 g:10-20 mL.

[0019] The present invention is further configured such that, in step (1), the ultrasonic extraction conditions are: extraction temperature is 40-50°C, extraction time is 30-40min, and extraction power is 400-500W.

[0020] The present invention is further configured such that, in step (1), after ultrasonic extraction, an SPE solid phase extraction column is used to assist in purifying the extract.

[0021] The present invention is further configured that the instrument conditions of the gas chromatography-mass spectrometry are:

[0022] The chromatographic column is a DB-WAX chromatographic column; the carrier gas is helium (purity ≥ 99.999%); the carrier gas flow rate is 0.8-1.1 mL / min; the injection port temperature is 100-200° C.; the program temperature is: the initial temperature is 25-40° C., maintained for 10 min, first heated to 100° C. at a rate of 20° C. / min, maintained for 8 min, then heated to 250° C. at a rate of 40° C. / min, and maintained for 8 min; the gas-gas interface temperature is 200-250° C.;

[0023] The ionization mode is EI; the ionization energy is 40-60 eV, the ion source temperature is 170-250°C; and the mass spectrometry scanning is SIM mode.

[0024] The present invention is further configured such that the retention time and characteristic ions of the (meth)acrylate compounds are shown in the following table:

[0025]

[0026]

[0027] The present invention is further configured that the preparation of the standard curve equation comprises the following steps:

[0028] S1: Accurately weigh an appropriate amount of the (meth)acrylate compound standard to be tested, dissolve it in ethyl acetate, make up to volume, and then dilute it into a series of gradient mixed standard working solutions;

[0029] S2: Inject the gradient mixed standard working solution into a gas chromatography-mass spectrometer to determine the (meth)acrylate compound to be measured and its peak area, draw a standard working curve with concentration as the horizontal coordinate and the peak area of ​​the (meth)acrylate compound as the vertical coordinate, and calculate the standard curve equation.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The invention adopts ultrasonic extraction-gas chromatography-mass spectrometry to realize simultaneous and accurate detection of 12 kinds of (methyl) acrylate compounds in textiles; the method of the invention is simple to operate, the detection process is easy to realize automation, the sensitivity is high, within the concentration range of 0.50-10.00 mg / L, the linear correlation coefficient is above 0.998, the detection limit range is 0.09 mg / kg-2.41 mg / kg, the quantitative limit is between 0.32 mg / kg-7.44 mg / kg, the spiked recovery rate is 87.71%-99.43%, the relative standard deviation (RSD) is 1.07%-2.81%, and the method has good accuracy and reproducibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a diagram of the extraction effects of different extraction agents.

[0033] Figure 2a-2g The following are the detection chromatograms using different extraction solvents.

[0034] Figure 3 This is a diagram showing the extraction effects of different extractants on actual positive samples.

[0035] Figure 4 a-4c is a graph showing the effect of the amount of extractant on the extraction of (meth)acrylate for spiked textiles of different materials.

[0036] Figure 5 a-5d are the extraction effect diagrams of (meth)acrylates of spiked textiles of different materials and actual positive samples at different extraction temperatures.

[0037] Figure 6 a-6d is the extraction effect diagram of (meth)acrylate of spiked textiles of different materials and actual positive samples at different extraction times.

[0038] Figure 7 a-7d is the extraction effect diagram of (meth)acrylate of spiked textiles of different materials and actual positive samples at different extraction powers.

[0039] Figure 8a-8e These are the detection chromatograms of (meth)acrylate using different chromatographic columns.

[0040] Fig. 9 This is a graph showing the effect of injection port temperature on (meth)acrylate detection.

[0041] Fig.10 This is a graph showing the effect of the initial temperature of heating on the detection of (meth)acrylate.

[0042] Fig.11 This is a graph showing the effect of heating rate on (meth)acrylate detection.

[0043] Fig.12 This is a graph showing the effect of termination temperature on (meth)acrylate detection.

[0044] Fig.13 This is a graph showing the effect of carrier gas flow rate on (meth)acrylate detection.

[0045] Fig.14 This is a graph showing the effect of ion source temperature on (meth)acrylate detection.

[0046] Fig.15 It is the GC-MS detection chromatogram of (meth)acrylate. DETAILED DESCRIPTION

[0047] The following is a clear and detailed description of the technical solution of the present invention through specific embodiments in conjunction with the accompanying drawings. It should be understood that the following embodiments are only part of the embodiments of the present invention, and other embodiments obtained by ordinary technicians in this field without creative work should be included in the protection scope of the present invention.

[0048] The materials used in the following examples are all conventional commercially available products. Experimental conditions not specified were performed according to the conditions recommended by the manufacturer or conventional experimental conditions in the art.

[0049] (1) Preparation of standard stock solution and mixed standard working solution:

[0050] Accurately weigh 0.2g of each of the 12 (meth)acrylate standard products, dissolve them in ethyl acetate, transfer them to a 10mL volumetric flask, and dilute to the mark to obtain a standard stock solution with a concentration of 2000mg / L. According to the experimental design, take the same volume of various (meth)acrylate standard stock solutions, put them into the same brown volumetric flask to avoid light, dilute with ethyl acetate, and prepare the required concentration for the experiment to obtain the mixed standard working solution. The mixed standard working solution must be prepared and used immediately.

[0051] The above 12 (meth)acrylate compounds include methyl acrylate (MAE), ethyl acrylate (EA), butyl acrylate (BA), tert-butyl acrylate (TBA), octadecyl acrylate (OA), methyl methacrylate (MMA), ethyl methacrylate (EM), butyl methacrylate (BM), hydroxyethyl methacrylate (HM), 2-ethylhexyl acrylate (2-EA), 2-phenoxyethyl acrylate (2-PA) and 2-methoxyethyl acrylate (EMEA).

[0052] (2) Preparation of spiked textiles:

[0053] Accurately weigh 1.00 g of blank adjacent fabrics of different materials, such as cotton, wool, polyester, and nylon, cut them into pieces smaller than 0.5 cm × 0.5 cm in size, and place them in a 50 mL sealable screw-mouth sample bottle. Measure 100 uL of 100 mg / L mixed standard working solution and drop it onto the cut blank adjacent fabrics. Seal the bottle mouth and let it stand for 15 minutes.

[0054] Example 1. Screening of sample pretreatment methods

[0055] 1.1 Selection of extraction agent

[0056] Extractants with different solubility were selected for the experiment. Seven spiked textiles of different materials (cotton, wool, polyester) were weighed. The content of mixed standard substances on each spiked textile was 10 mg / kg. They were placed in a 50 mL screw-mouth sample bottle, and extractants N, N-dimethylformyl, methyl tert-butyl ether, methanol, dichloromethane, acetonitrile, ethyl acetate and n-hexane were added respectively. After ultrasonication at 45 ° C for 35 minutes, 1 mL of the extract was measured and filtered through a filter white head and placed in a 2 mL injection bottle. After GC-MS detection, three groups of parallel experiments were set up, and the results were calculated as the average. At the same time, 100 μL of 100 mg / L mixed standard stock solution was added to the screw-mouth sample bottle, and the same volume of extractant was added without adding the lining fabric, and a control experiment was carried out to calculate the extraction rate.

[0057] At the same time, a more representative polyacrylate waterproof coating fabric synthesized with octadecyl acrylate as the monomer was selected as the actual positive sample, and a synchronous extraction experiment was carried out: 1g of the actual positive sample was weighed, cut into small pieces of 0.5cm×0.5cm, placed in a 50mL sealable screw-mouth sample bottle, and the above-mentioned extractants with different solubilities were added to perform extraction under the same extraction conditions. After the extraction, the peak area was detected by GC-MS, and 3 groups of parallel experiments were performed, and the results were calculated as the average value.

[0058] Figure 1 Extraction effects of different extractants on spiked textiles; Figure 2a to 2g The detection chromatograms of different extractants; Figure 3 The extraction effects of different extraction agents were used for actual positive samples.

[0059] First, from Figure 1 It can be seen that all the extractants can extract three typical substances: hydroxyethyl methacrylate (HM), 2-phenoxyethyl acrylate (2-PA) and octadecyl acrylate (OA), and the extraction rate of ethyl acetate solvent for the three acrylates is higher than that of the other six solvents, and it has a certain universality; in addition, from Figure 2a to 2g It can be seen that ethyl acetate can extract all substances, and the peak area value is the highest, and the extraction effect is the best; finally, Figure 3 It can be seen that in the verification of waterproof coating fabric containing octadecyl acrylate that can be extracted in all extraction solvents, it can be seen that the peak area of ​​ethyl acetate is relatively still the highest. And considering the characteristics of ethyl acetate such as low toxicity, low price, and similar polarity to acrylate, ethyl acetate was selected as the extraction reagent for sample pretreatment.

[0060] 1.2 Research on extraction methods

[0061] Weigh 1.0g of spiked textiles of different materials (cotton, wool, polyester) and 3 portions, the content of mixed standard substances on each spiked textile is 10mg / kg, put them in a 50mL screw-mouth sample bottle, and add 10mL of chromatographic grade ethyl acetate. Each type of spiked textile sample is extracted by ultrasonic extraction, Soxhlet extraction and oscillation extraction. After the extraction, 1mL of the extract is filtered through a filter and placed in a 2mL injection bottle. GC-MS analysis is performed. Three parallel experiments are performed for each extraction method, and the results are averaged. At the same time, 100μL of 100mg / L mixed standard stock solution is added to the screw-mouth sample bottle, and the same volume of extractant is added without adding the lining fabric, and a control experiment is carried out to calculate the extraction rate.

[0062] At the same time, a more representative polyacrylate waterproof coating fabric synthesized with octadecyl acrylate as the monomer was selected as the actual positive sample, and a synchronous extraction experiment was carried out: 1 g of the actual positive sample was weighed, cut into 0.5 cm × 0.5 cm pieces, and placed in a 50 mL sealable screw-mouth sample bottle, and the above-mentioned extraction experiments were carried out with different extraction methods. After the extraction, the peak area was detected by GC-MS. Three groups of parallel experiments were carried out, and the results were averaged. The extraction rates of different extraction methods are shown in Table 2.

[0063] Table 2 Extraction rate of different extraction methods (n=3)

[0064]

[0065] As can be seen from Table 2, the extraction rates of Soxhlet extraction and ultrasonic extraction are higher than those of mechanical oscillation. However, considering that the Soxhlet extraction method takes a long time (generally more than 6 hours), the extraction steps are complicated, and a large amount of organic reagents are consumed, the rapid and efficient ultrasonic extraction method is selected after comprehensive consideration. In addition, after ultrasonic extraction, SPE solid phase extraction columns can be used to further purify and extract (meth) acrylate compounds in textiles.

[0066] 1.3 Study on the volume of extractant

[0067] Weigh 1.0g of 4 spiked textiles of different materials (cotton, wool, polyester), the content of mixed standard substances on each spiked fabric is 10mg / kg, put them in 50mL screw-mouth sample bottles, add (5, 10, 15, 20)mL of chromatographic grade ethyl acetate, ultrasonicate at 45℃ for 35min, after the end of ultrasonication, measure 1mL of extract, filter through filter white head, put it into a 2mL injection bottle, analyze and detect by GC-MS, conduct 3 groups of parallel experiments, and calculate the average value of the results. At the same time, add 100μL of 100mg / L mixed standard stock solution to the screw-mouth sample bottle, add (5, 10, 15, 20)mL of extractant without adding lining fabric, and conduct control experiments to calculate the extraction rate.

[0068] Figure 4 a-4c are the extraction rates of (meth)acrylates of spiked textiles of different materials at different extractant dosages, among which: Figure 4 a is cotton fabric, Figure 4 b is wool fabric, Figure 4 c is polyester fiber.

[0069] It can be seen from the figure that with the increase in the amount of extraction reagent, the extraction rate shows a trend of first rising and then stabilizing. When the extraction amount is 5mL, the extraction rate is the lowest. The main reason is that the amount of extraction agent is too small to immerse 1.0g of the fabric to be tested, that is, the (meth) acrylate on the fabric cannot be completely extracted. When the amount of extraction agent is 10mL, 15mL, and 20mL, the spiked recovery rate of acrylate is close. Therefore, the mass volume ratio of the textile sample to be tested and the extraction agent is selected as 1g:10~20mL.

[0070] 1.4 Study on extraction temperature

[0071] In ultrasonic extraction, extraction temperature is one of the important factors affecting the extraction results. The boiling point of the extractant used in this experiment is 77°C, and the indoor temperature of the test room is 25°C. Ultrasonic extraction requires that the extraction temperature be lower than the boiling point of the selected extraction reagent. Therefore, the following study explores the effect of extraction temperature on the extraction results within a temperature range of 30 to 50°C.

[0072] Weigh 1.0g of 5 spiked textiles of different materials (cotton, wool, polyester), the content of mixed standard substances on each spiked fabric is 10mg / kg, put them in a 50mL screw-mouth sample bottle, add 10mL of chromatographic grade ethyl acetate and ultrasonicate for 35min at different extraction temperatures (30℃, 35℃, 40℃, 45℃, 50℃), after the end of ultrasonication, measure 1mL of extract, filter it through a filter, put it into a 2mL injection bottle, and perform GC-MS analysis and detection. Perform 3 sets of parallel experiments, and calculate the average value of the results. At the same time, add 100μL of 100mg / L mixed standard stock solution to the screw-mouth sample bottle, add 10mL of extractant without adding the lining fabric, and perform control experiments to calculate the extraction rate.

[0073] At the same time, a more representative polyacrylate waterproof coating fabric synthesized with octadecyl acrylate as the monomer was selected as the actual positive sample, and a synchronous extraction experiment was carried out: 1 g of the actual positive sample was weighed, cut into 0.5 cm × 0.5 cm pieces, placed in a 50 mL sealable screw-mouth sample bottle, and 10 mL of chromatographic grade ethyl acetate was added. The same extraction method was used, and the extraction was carried out at different extraction temperatures (30°C, 35°C, 40°C, 45°C, 50°C). After the extraction, the peak area was detected by GC-MS. Three groups of parallel experiments were carried out, and the results were calculated as the average value.

[0074] Figure 5 a-5d are the extraction rates of (meth)acrylates of spiked textiles of different materials and actual positive samples at different extraction temperatures, among which, Figure 5 a is cotton fabric, Figure 5 b is wool fabric, Figure 5 c is polyester fiber, Figure 5 d is the actual positive sample.

[0075] As can be seen from the figure, as the extraction temperature increases, the intermolecular thermal motion intensifies. Under the action of the extractant, the (meth)acrylate monomer is desorbed from the fabric and enters the extract. When the temperature rises to 45°C, the (meth)acrylate on the fabric is basically completely desorbed and reaches equilibrium. Increasing the extraction temperature can no longer improve the extraction effect. Therefore, in ultrasonic extraction, the extraction temperature is selected to be 40-50°C.

[0076] 1.5 Study on extraction time

[0077] Weigh 1.0g of 5 spiked textiles of different materials (cotton, wool, polyester), the content of mixed standard substances on each spiked fabric is 10mg / kg, put them in a 50mL screw-mouth sample bottle, add 10mL of chromatographic grade ethyl acetate and ultrasonically extract at 45℃ for 20min, 25min, 30min, 35min, 40min. After the end of the ultrasound, filter 1mL of the extract and put it in a 2mL injection bottle, and test it on the GC-MS machine. Perform 3 sets of parallel experiments and calculate the average value of the results. At the same time, add 100μL of 100mg / L mixed standard stock solution to the screw-mouth sample bottle, add 10mL of extractant without adding the adjacent fabric and test it on the machine, and perform a control experiment to calculate the extraction rate.

[0078] At the same time, a more representative polyacrylate waterproof coating fabric synthesized with octadecyl acrylate as the monomer was selected as the actual positive sample, and a synchronous extraction experiment was carried out: 1g of the actual positive sample was weighed, cut into 0.5cm×0.5cm pieces, placed in a 50mL sealable screw-mouth sample bottle, and 10mL of chromatographic grade ethyl acetate was added. The same extraction method was used, and ultrasonic extraction was performed at 45°C for 20min, 25min, 30min, 35min, and 40min respectively. After the extraction, the peak area was detected by GC-MS. Three groups of parallel experiments were carried out, and the results were calculated as the average value.

[0079] Figure 6 a-6d are the extraction rates of (meth)acrylates of spiked textiles of different materials and actual positive samples at different extraction times, among which, Figure 6 a is cotton fabric, Figure 6 b is wool fabric, Figure 6 c is polyester fiber, Figure 6 d is the actual positive sample.

[0080] As can be seen from the figure, the extraction time is between 20 and 35 minutes, and the extraction time is positively correlated with the extraction rate. After 35 minutes, as time goes by, the extraction rate no longer changes much and tends to be balanced. Therefore, in ultrasonic extraction, the extraction time is selected to be 30 to 40 minutes.

[0081] 1.6 Research on extraction efficiency

[0082] Weigh 5 portions of spiked textiles of different materials (cotton, wool, polyester), and place the mixed standard substance content of each spiked fabric at 10 mg / kg in a 50 mL screw-mouth sample bottle. Add 10 mL of chromatographic grade ethyl acetate and ultrasonically extract for 35 min at 45 ° C. The ultrasonic extraction power is 300 W, 350 W, 400 W, 450 W, and 500 W. After the ultrasonic treatment, filter 1 mL of the extract and place it in a 2 mL injection bottle. GC-MS is used for detection. Three groups of parallel experiments are performed, and the results are calculated as the average value. At the same time, 100 μL of 100 mg / L mixed standard stock solution is added to the screw-mouth sample bottle, and 10 mL of the extractant is added without adding the adjacent fabric for detection. A control experiment is performed to calculate the extraction rate.

[0083] At the same time, a more representative polyacrylate waterproof coating fabric synthesized with octadecyl acrylate as the monomer was selected as the actual positive sample, and a synchronous extraction experiment was carried out: 1g of the actual positive sample was weighed, cut into 0.5cm×0.5cm fragments, placed in a 50mL sealable screw-mouth sample bottle, and 10mL of chromatographic grade ethyl acetate was added. The same extraction method was used, and ultrasonic extraction was performed at 45°C for 35min. The ultrasonic extraction powers were 300W, 350W, 400W, 450W, and 500W, respectively. After the extraction, the peak area was detected by GC-MS. Three groups of parallel experiments were carried out, and the results were calculated as the average value.

[0084] Figure 7 a-7d are the extraction rates of (meth)acrylates of spiked textiles of different materials and actual positive samples at different extraction powers, among which, Figure 7 a is cotton fabric, Figure 7 b is wool fabric, Figure 7 c is polyester fiber, Figure 7 d is the actual positive sample.

[0085] As can be seen from the figure, when the extraction power is in the range of 300W to 450W, as the extraction ultrasonic power increases, the extraction rate and peak area of ​​(meth)acrylates also increase continuously, and then gradually tend to balance. However, considering that the maximum power of the ultrasonic extractor in the actual experiment is 500W, and the boiling points of ethyl acetate and the target substance 2-methoxyethyl acrylate are relatively low, when the ultrasonic power is too high, the thermal effect of the ultrasonic wave will generate a lot of heat, causing the temperature of the ultrasonic water bath to change and rise, and then the temperature of the test object and the extraction reagent in the test tube will also increase. Therefore, the extraction power is selected to be 400-500W.

[0086] Example 2: Study on GC-MS instrument conditions

[0087] 2.1 Selection of chromatographic columns

[0088] In gas chromatography detection, analytes of different polarities are adsorbed and desorbed by the stationary phase in the chromatographic column to achieve separation. The selection of the stationary phase is particularly important. Not only the polarity of the analyte and the stationary phase should be considered, but also the separation degree and column efficiency during the chromatographic analysis process should be considered. This experiment measured a large number of (meth)acrylates, and the polarity and boiling point differences between the substances were large, so choosing a suitable chromatographic column is particularly critical.

[0089] In this experiment, five gas chromatography columns with different polarities were selected, namely DB-5 column (weak polarity column), DB-17 column (medium polarity column), DB-35 column (weak medium polarity column), DB-624 column (medium polarity capillary column) and DB-WAX column (strong polarity column). Under the same detection conditions (inlet temperature of 200°C, heating program: initial temperature 40°C, hold for 10 min, heat to 100°C at 20°C / min and hold for 8 min, finally heat to 250°C at 40°C / min and hold for 8 min, carrier gas is helium (purity ≥99.999%), carrier gas flow rate is 1 mL / min, gas-gas interface temperature is 250°C, ionization mode is EI; ionization energy is 60 eV, mass spectrometry scanning is SIM mode, ion source temperature is 230°C, transmission line temperature is 250°C), 50 mg / L mixed standard working solution was detected, and the peak shape, separation and response value detected by different chromatographic columns were observed. Figure 8a-8e The detection chromatograms of different chromatographic columns are shown in Figure 2.

[0090] As can be seen from the figure, the peak conditions of different chromatographic columns are different. The peak elution time of the DB-17 column is relatively early, and only 5 substances have peaks; the response value of DB-5 is not high, and the peak elution time is too early, which is very likely to overlap with the solvent peak, and only 6 substances have peaks, affecting the experimental analysis; the DB-624 column cannot make methyl acrylate and octadecyl acrylate peaks; the DB-35 column cannot make methyl acrylate peak and there is an unstable baseline problem. When the DB-WAX column is selected, all 12 substances can elute, and the peak times do not interfere with each other. The higher response value is more in line with the experimental detection requirements, so the DB-WAX column is selected.

[0091] 2.2 Investigation of injection port temperature

[0092] The injection port temperature in gas chromatography-mass spectrometry is a factor that has a great influence on the final test results. Generally, the injection port temperature is required to be higher than the boiling point of the analyte (the boiling point of octadecyl acrylate is 400°C, and the boiling points of other acrylate analytes are below 150°C), but considering the need to ensure the service life of the instrument (the maximum temperature of the chromatographic column can only reach 260°C), the lowest temperature of 160°C is selected, and six different temperatures between 160 and 260°C are set for condition exploration.

[0093] A 20 mg / L (meth)acrylate mixed standard working solution was prepared and a DB-WAX gas chromatographic column was used. The temperature program was the same as that in the above "(1) Selection of chromatographic column" except for the injection temperature. When other instrument conditions remained unchanged, the injection temperatures of the gas chromatograph were set to 160°C, 180°C, 200°C, 220°C, and 240°C, respectively. The peak areas and separations of (meth)acrylates at different temperatures were measured to determine the optimal injection temperature. Fig. 9 The effect of different injection port temperatures on the detection of (meth)acrylates.

[0094] from Fig. 9 It can be seen that as the injection port temperature increases, the peak area of ​​the detected (meth)acrylate gradually increases. When the temperature is raised to 200°C, the peak area of ​​the (meth)acrylate gradually decreases. Therefore, the injection port temperature is selected to be 180-200°C, preferably 200°C.

[0095] 2.3 Study on the heating program

[0096] There are two types of heating programs: single-stage linear heating program and multi-stage linear heating program. Single-stage heating program is generally used for homologues with a wide boiling point range, and multi-stage heating program is used when containing different types of compounds. A good heating program can effectively separate the target substances and is the basis for qualitative and quantitative determination of the analyte. In this embodiment, the appropriate heating program is explored by optimizing the initial temperature, heating rate and termination temperature.

[0097] (1) Optimization of initial temperature: A 20 mg / L (meth)acrylate mixed standard working solution was prepared and a DB-WAX gas chromatographic column was used. The temperature program was the same as that in the above “2.1 Selection of chromatographic column” except for the initial temperature. When other instrument conditions remained unchanged, the initial temperatures were set to 35°C, 40°C, 60°C and 80°C, respectively. The peak area and separation of (meth)acrylate at different temperatures were measured to determine the optimal initial temperature. The different initial temperature programs are shown in Table 3.

[0098] Table 3 Heating program with different initial temperatures

[0099]

[0100] The initial temperature must ensure that the target components can be completely separated, while taking into account the timeliness of the analysis. The analysis time should not be too long. If the initial temperature of the gas chromatography column is too high, not only will the separation of the target substance decrease, the retention time shorten, and the chromatographic peak become narrower and higher, but also the initial temperature rise is too fast, which will affect the peak of the previous substance; if the initial temperature is too low, the separation will increase and the analysis time will be extended. Therefore, this experiment mainly considers the compatibility of retention time and peak area to explore the initial temperature of the gas chromatography column. The results are as follows: Fig.10 shown.

[0101] from Fig.10 It can be seen that when the initial temperature is 60℃ and 80℃, the initial temperature is too high, which affects the peak of the substance, and only makes the three substances with retention time exceeding 20min peak. When the initial temperature is 35℃ and 40℃, the peak of the target substance is better and the separation is higher, but relatively speaking, the peak area of ​​the initial temperature of 35℃ is lower, and the baseline is unstable in the later stage of the detection. Therefore, the initial temperature of (meth)acrylate detection is selected to be 35-40℃, preferably 40℃.

[0102] (2) Optimization of heating rate: A 20 mg / L mixed standard working solution of acrylic esters was prepared and a DB-WAX gas chromatography column was used. The heating program was the same as that in the above “2.1 Selection of Chromatographic Column” except for the heating rate. When other instrument conditions remained unchanged, multi-stage linear heating programs with different heating rates were set. The peak area and separation degree of (meth)acrylate at different rates were measured to determine the optimal heating program. The different heating rate programs are shown in Table 4.

[0103] Table 4 Heating program with different heating rates

[0104]

[0105] A faster heating rate of the gas chromatography column can shorten the analysis time, but at the same time it will reduce the separation degree. A lower heating rate will increase the separation degree and prolong the analysis time for high boiling point components, which will make the peak shape wider. A heating rate that is too fast or too slow will affect the peak appearance and thus the experimental results. Therefore, this experiment mainly considers the compatibility of retention time and peak area, and measures four (meth)acrylates with different heating rates to explore the heating rate of the gas chromatography column. The results are as follows: Fig.11 shown.

[0106] from Fig.11 It can be seen that when the heating rate is 10℃ / min and 20℃ / min, the heating rate is too slow, resulting in the inability of hydroxyethyl methacrylate, 2-phenoxyethyl acrylate, and octadecyl acrylate, which have long retention times, to elute; when the heating rate is 80℃ / min, the heating rate is too fast, which makes the overall peak time of the target object earlier, and the overall peak area decreases compared with 40℃ / min, and the baseline is unstable in the later stage of the detection. Therefore, after comprehensive consideration, it is selected to first heat up to 100℃ at a heating rate of 20℃ / min, and then heat up to 250℃ at a heating rate of 40℃ / min as the heating program for (meth)acrylate detection.

[0107] (3) Optimization of the termination temperature: A 20 mg / L (meth)acrylate mixed standard working solution was prepared and a DB-WAX gas chromatography column was used. The temperature program was the same as that in the above "2.1 Selection of Chromatographic Column" except for the termination temperature. With other instrument conditions unchanged, the termination temperatures were set at 150°C, 200°C, and 250°C, respectively. The peak area and separation of (meth)acrylate at different temperatures were measured to determine the optimal termination temperature. The termination temperature program is shown in Table 5.

[0108] Table 5 Heating program for different termination temperatures

[0109]

[0110]

[0111] The choice of termination temperature should take into account the component with the highest boiling point and the maximum operating temperature of the stationary phase. In this experiment, the compatibility of retention time and peak area was considered while ensuring the full performance of the DB-WAX column. (Meth)acrylates at three different termination temperatures were measured to explore the termination temperature of the heating program. The results are as follows: Fig.12 shown.

[0112] from Fig.12 It can be seen that when the termination temperature is 150℃, the peak area of ​​(meth)acrylate is low, and hydroxyethyl methacrylate and octadecyl acrylate cannot produce peaks; when the termination temperature is 200℃, the peak area of ​​(meth)acrylate is increased compared with 150℃, but 2-phenoxyethyl acrylate still cannot produce peaks; when the termination temperature is 250℃, the 12 (meth)acrylates have good separation and peak area. Therefore, 250℃ is selected as the termination temperature of the (meth)acrylate detection heating program.

[0113] Through the above optimization, the temperature program of the gas chromatography column was finally determined as follows: initial temperature 40°C, maintained for 10 min, first heated to 100°C at a rate of 20°C / min, maintained for 8 min, then heated to 250°C at a rate of 40°C / min, and maintained for 8 min.

[0114] 2.4 Investigation of carrier gas flow rate

[0115] In gas chromatography-mass spectrometry, different carrier gas flow rates have a great impact on peak elution time and peak shape. Appropriate carrier gas flow rates can improve column efficiency, reduce band broadening, and make peaks sharp and symmetrical.

[0116] In this experiment, a 20 mg / L (meth)acrylate mixed standard working solution was prepared, and a DB-WAX gas chromatography column was used. The temperature program was the same as that set in the above "2.1 Selection of chromatographic column". When other instrument conditions remained unchanged, three parallel experiments were set up with a carrier gas flow rate in the range of 0.4 mL / min to 1.1 mL / min. The peak area and separation degree of (meth)acrylate at different flow rates were measured to determine the optimal carrier gas flow rate. The effect of different carrier gas flow rates on the determination of 20 mg / L (meth)acrylate mixed standard working solution is shown in Figure 2. Fig.13 shown.

[0117] from Fig.13 It can be seen that with the continuous increase of the carrier gas flow rate, the peak area of ​​(meth)acrylate shows a trend of first increasing and then decreasing. Therefore, the carrier gas flow rate is selected to be 0.8-1.1 mL / min.

[0118] 2.5 Investigation of ion source temperature

[0119] The ion source is mainly used to bombard the substances separated by gas chromatography into fragment ions, and then detect the fragment ions of the target substance, and perform qualitative and quantitative analysis based on the relative molecular mass. Therefore, it is necessary to ensure that the chromatographic separation substances are completely bombarded during the entire process. On the one hand, it is necessary to prevent the ion source temperature from being too low, causing the bombarded fragment ions to contaminate the ion source, and on the other hand, it is also necessary to prevent the ion source temperature from being too high, causing the ion source port of the equipment to age.

[0120] In order to obtain the optimal ion source temperature, this experiment prepared a 20 mg / L (meth)acrylate mixed standard working solution, used a DB-WAX gas chromatography column, and the heating program was the same as that set in the above "2.1 Selection of chromatographic column". When other instrument conditions remained unchanged, the ion source temperatures were set at 150°C, 170°C, 190°C, 210°C, 230°C, and 250°C, respectively. Three parallel experiments were set up to measure the peak area and separation of (meth)acrylate at different temperatures and determine the optimal ion source temperature.

[0121] The influence of different ion source temperatures on the determination of 20 mg / L (meth)acrylate mixed standard working solution is as follows: Fig.14 shown.

[0122] Depend on Fig.14 It can be seen that when the ion source temperature is 170°C to 250°C, the corresponding peak areas of (meth)acrylates are all high, with no significant difference.

[0123] 2.6 Retention time and characteristic ions

[0124] A 20 mg / L (meth)acrylate mixed standard working solution was prepared and injected into a gas chromatography-mass spectrometer. The optimal instrument conditions optimized in Examples 2.1 to 2.5 were used to detect the solution. The retention times and characteristic ions of 12 (meth)acrylate target substances and the corresponding gas chromatograms were obtained, as shown in Tables 6 and 7, respectively. Fig.15 Among them, the best instrument conditions are as follows:

[0125] Select DB-WAX column; set the injection port temperature to 180℃; temperature program: initial temperature is 40℃, hold for 10min, first increase the temperature to 100℃ at a rate of 20℃ / min, hold for 8min, then increase the temperature to 250℃ at a rate of 40℃ / min, and hold for 8min; ion source temperature is 230℃; carrier gas flow rate is 1.0mL / min.

[0126] Table 6 Retention time and characteristic ions of (meth)acrylate

[0127]

[0128] Example 3: Methodological Verification

[0129] 3.1 Linear relationship and detection limit

[0130] 1 mL of the (meth)acrylate mixed standard working solution with a concentration gradient of 0.5 mg / L, 1 mg / L, 2 mg / L, 5 mg / L, and 10 mg / L was respectively drawn into a 2 mL injection bottle, and then injected into a gas chromatograph-mass spectrometer for detection to obtain a gas chromatograph-mass spectrometer, and a standard curve was drawn with the sample concentration as the abscissa and the peak area as the ordinate. The test conditions of the gas chromatograph-mass spectrometer are the same as those in the above "2.6 Retention time and characteristic ions", and the linear ranges, linear equations, and correlation coefficients of the 12 (meth)acrylates obtained are shown in Table 7 below.

[0131] Table 7 Linear range, linear equation and correlation coefficient of 12 (meth)acrylates

[0132]

[0133] As shown in Table 7, in the concentration range of 0.50 mg / L-10.00 mg / L, this method has a good linear relationship, and the linear correlation coefficients of the standard curves of the 12 target compounds are all above 0.998, which can meet the actual test needs.

[0134] According to the above method, the detection limit and quantification limit of 12 kinds of (meth)acrylates were measured through low concentration spike test. The results are shown in Table 8:

[0135] Table 8 Detection limit and quantification limit test results of 12 kinds of (meth)acrylates

[0136]

[0137]

[0138] It can be seen from Table 8 that the detection limit of this method is in the range of 0.09 mg / kg to 2.41 mg / kg, and the quantification limit is in the range of 0.32 mg / kg to 7.44 mg / kg, which can meet the daily detection requirements.

[0139] 3.2 Recovery and precision

[0140] In order to reflect the universality of the detection method of the present invention, four standard adjacent fabrics of different materials (cotton fiber, wool fiber, polyester fiber, polyamide fiber) were weighed, and three different spiked amounts (5 mg / kg, 500 mg / kg, 1000 mg / kg) in the range of 5 to 100 mg / kg were selected respectively to prepare spiked textiles.

[0141] The spiked textile was placed in a reactor, and ethyl acetate was added as an extracting liquid. The mass volume ratio of the spiked textile and the extracting solvent was 1 g: 10 mL. The product was placed in an ultrasonic generator at 40°C, and the extraction power was 400 W. The extraction was performed for 30 min. The obtained extract was the test liquid. The test liquid was injected into a liquid chromatography-mass spectrometer for detection. The detection conditions of the gas chromatography-mass spectrometer were the same as those in the above "2.6 Retention time and characteristic ions". Six parallel tests were performed for each experiment, and the peak area was recorded. The recovery rate and relative standard deviation (RSD) were calculated to obtain the results described in Table 9 below.

[0142] Table 9 Recovery and relative standard deviation of (meth)acrylate detected by GC-MS method (n=6)

[0143]

[0144]

[0145] The results showed that the spiked recoveries of 12 (meth)acrylates in cotton fabrics were between 87.71% and 94.90%, the spiked recoveries of 12 (meth)acrylates in wool fabrics were between 88.89% and 96.10%, the spiked recoveries of 12 (meth)acrylates in polyester fibers were between 93.69% and 99.43%, and the spiked recoveries of 12 (meth)acrylates in polyamide fibers were between 93.59% and 99.03%.

[0146] The relative standard deviation (RSD) of the method for detecting (meth)acrylates in different textiles is between 1.07% and 2.81%, indicating that the ultrasonic extraction-gas chromatography-mass spectrometry method has good reproducibility and accuracy for the detection of (meth)acrylates in textiles.

[0147] Application Example 1

[0148] The method for determining (meth)acrylate in a positive sample to be tested comprises the following steps:

[0149] (1) Accurately weigh 1 g of the positive sample to be tested, cut the sample into pieces no larger than 0.5 cm × 0.5 cm, place it in a reactor, add 10 mL of the extraction solvent ethyl acetate, and perform ultrasonic extraction at an extraction temperature of 40°C, an extraction time of 30 min, and an extraction power of 400 W. The obtained extract is the test solution;

[0150] (2) The standard working curve equation and the test conditions of the gas chromatography-mass spectrometry are the same as those in “3.1 Linear Relationship and Detection Limit”.

[0151] (3) The test liquid of step (1) is injected into a gas chromatography-mass spectrometer for detection. The test conditions are the same as those of step (2) above. The (meth)acrylate compounds and their peak areas are measured and analyzed according to the standard curve equation.

[0152] Finally, the content of octadecyl acrylate in the positive sample was measured to be 2.72 mg / kg, and the content of methyl methacrylate was 1.88 mg / kg, and other (meth)acrylates were not detected.

[0153] The above description is only a preferred embodiment of the present invention, and does not limit the protection scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention description and drawings is also included in the protection scope of the present invention.

Claims

1. A method for determining (meth)acrylate compounds in textiles, characterized in that: The following steps are involved: (1) placing an accurately weighed textile sample to be tested in a reactor, adding an extractant for ultrasonic extraction, and obtaining an extract; (2) Injecting the above extract into a gas chromatography-mass spectrometer to determine the (meth)acrylate compounds and their peak areas, and calculating the content of the (meth)acrylate compounds in the textile sample to be tested according to the standard curve equation.

2. The method for determining (meth)acrylate compounds in textiles according to claim 1, characterized in that: The (meth)acrylate compounds include methyl acrylate, ethyl acrylate, butyl acrylate, tert-butyl acrylate, octadecyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, 2-ethylhexyl acrylate, 2-phenoxyethyl acrylate and 2-methoxyethyl acrylate.

3. The method for determining (meth)acrylate compounds in textiles according to claim 1, characterized in that: In step (1), the extractant is ethyl acetate.

4. The method for determining (meth)acrylate compounds in textiles according to claim 1, characterized in that: In step (1), the mass volume ratio of the textile sample to be tested and the extractant is 1 g:10-20 mL.

5. The method for determining (meth)acrylate compounds in textiles according to claim 1, characterized in that: In step (1), the ultrasonic extraction conditions are: extraction temperature is 40-50°C, extraction time is 30-40min, and extraction power is 400-500W.

6. The method for determining (meth)acrylate compounds in textiles according to claim 1, characterized in that: In step (1), after ultrasonic extraction, an SPE solid phase extraction column is used to purify the extract.

7. The method for determining (meth)acrylate compounds in textiles according to claim 1, characterized in that: The instrument conditions of the gas chromatography-mass spectrometry are: The chromatographic column is a DB-WAX chromatographic column; the carrier gas is helium (purity ≥ 99.999%); the carrier gas flow rate is 0.8-1.1 mL / min; the injection port temperature is 100-200° C.; the program temperature is: the initial temperature is 25-40° C., maintained for 10 min, first heated to 100° C. at a rate of 20° C. / min, maintained for 8 min, then heated to 250° C. at a rate of 40° C. / min, and maintained for 8 min; the gas-gas interface temperature is 200-250° C.; The ionization mode is EI; the ionization energy is 40-60 eV, the ion source temperature is 170-250°C; and the mass spectrometry scanning is SIM mode.

8. The method for determining (meth)acrylate compounds in textiles according to claim 1, characterized in that: The retention time and characteristic ions of the (meth)acrylate compounds are shown in the following table:

9. The method for determining (meth)acrylate compounds in textiles according to claim 1, characterized in that: The preparation of the standard curve equation comprises the following steps: S1: Accurately weigh an appropriate amount of the (meth)acrylate compound standard to be tested, dissolve it in ethyl acetate, make up to volume, and then dilute it into a series of gradient mixed standard working solutions; S2: Inject the gradient mixed standard working solution into a gas chromatography-mass spectrometer to determine the (meth)acrylate compound to be measured and its peak area, draw a standard working curve with concentration as the horizontal coordinate and the peak area of ​​the (meth)acrylate compound as the vertical coordinate, and calculate the standard curve equation.

Images