Method for determining (meth)acrylic compounds in a textile

Abstract

The application discloses a kind of (methyl) acrylic compound determination method in textile, comprising the following steps: (1) accurately taking the textile sample to be measured, placed in reactor, added extractant is extracted by ultrasonic, obtains test solution;(2) the test solution is injected into high performance liquid chromatography-mass spectrometry, determines (methyl) acrylic compound and peak area, and the content of (methyl) acrylic compound in the textile sample to be measured is calculated according to standard curve equation.The present application can realize the accurate detection of acrylic acid and methacrylic acid in textile simultaneously by using ultrasonic extraction pretreatment-high performance liquid chromatography-mass spectrometry, and has high sensitivity, simple operation, can satisfy actual demand, in 0.5mg / L~100mg / L concentration range, linear correlation coefficient can reach 0.993 above, acrylic acid detection limit is 1.80mg / kg, and the limit of quantification is 5.30mg / kg;Methacrylic acid detection limit is 0.77mg / kg, and the limit of quantification is 2.40mg / kg;Spiked recovery is 81.74%~99.10%, and relative standard deviation is 1.04%~2.89%.

Description

Technical Field

[0001] This invention belongs to the field of detection technology, specifically relating to a method for determining (meth)acrylic acid compounds in textiles. Background Technology

[0002] Textiles have long been an indispensable part of daily life, and their safety and environmental protection have received widespread attention both domestically and internationally. Relevant laws and regulations stipulate that, in addition to meeting production requirements for their inherent quality, textiles must also meet safety regulations regarding human health and the environment during processing and use. In recent years, with the continuous improvement of Chinese residents' consumption levels, the demand for functional textiles has also been increasing. Among the methods for achieving functional finishing of textiles, coating is one of the most common finishing methods. Common coatings include polyacrylate coatings and polyurethane coatings. Residual monomers in polymer coatings can not only harm the human body during use but also significantly reduce product quality.

[0003] International Textile Environmental Certification Standards The Blue Label Certification (BSSL) Consumer Safety Limits List (v13.0) provides the limits and corresponding safety limits for (meth)acrylic acid in textiles, as shown in Table 1 below:

[0004] Table 1BSSL Consumer Safety Limits for Acrylic Acid: List of Limits

[0005]

[0006] Note: A represents infant and toddler textile products; B represents textile products that come into direct contact with the skin; C represents textile products that do not come into direct contact with the skin.

[0007] Although restrictions and regulations have been established regarding the residue of (meth)acrylic acid in textiles, research on detection techniques for (meth)acrylic acid residues in textiles is relatively limited in the field of eco-textile testing technology. Establishing detection methods for (meth)acrylic acid in eco-textiles that conform to international testing standards and conducting research on (meth)acrylic acid residue detection techniques in eco-textiles are of great significance for the further expansion of my country's textile import and export trade. Summary of the Invention

[0008] To address the aforementioned problems in the prior art, this invention proposes a method for determining (meth)acrylic acid compounds in textiles. By employing ultrasonic extraction pretreatment conditions and HPLC-MS analysis conditions, an HPLC-MS analytical method for the simultaneous detection of (meth)acrylic acid in textiles is established, thereby achieving efficient detection of (meth)acrylic acid compounds.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0010] A method for determining (meth)acrylic acid compounds in textiles, comprising the following steps:

[0011] (1) Accurately weigh the textile sample to be tested, place it in a reactor, add the extractant and perform ultrasonic extraction to obtain the test solution;

[0012] (2) Inject the test solution into a high performance liquid chromatography-mass spectrometry instrument to determine the (meth)acrylic acid compounds and their peak areas, and calculate the content of (meth)acrylic acid compounds in the textile sample to be tested according to the standard curve equation.

[0013] The present invention is further configured such that the (meth)acrylic acid compound includes acrylic acid and methacrylic acid.

[0014] The present invention is further configured such that, in step (1), the mass-to-volume ratio of the textile sample to be tested and the extractant is 1 g: (10-20) mL.

[0015] The present invention is further configured such that, in step (1), the extractant is methanol.

[0016] The present invention is further configured such that, in step (1), the ultrasonic extraction conditions are: extraction temperature of 40-60℃; extraction time of 40-45 min; and extraction power of 400-500 W.

[0017] The present invention is further configured such that, in step (2), the testing conditions of the high-performance liquid chromatography-mass spectrometry instrument are:

[0018] A ZORBAX Eclipse Plus C18 column was selected, with ultrapure water and methanol in a ratio of 95:5 as the mobile phase. 0.005–0.01 mol / L ammonium acetate and 1–2 mL / L ammonia water were added. The response value and resolution were adjusted, and the carrier gas flow rate was 0.1 mL / min.

[0019] The ion source is an ion source with Jet Stream electrospray (ESI) and the fragmentation voltage is 40-70V.

[0020] The present invention further specifies that the retention time and characteristic ions of the (meth)acrylic acid compounds are shown in the table below:

[0021]

[0022] The present invention is further configured such that, in step (2), the process of generating the standard curve equation is as follows:

[0023] S1: Accurately weigh an appropriate amount of the (meth)acrylic acid compound standard to be tested, dissolve it in methanol, make up to volume, and then dilute it into a series of gradient mixed standard working solutions;

[0024] S2: Inject the gradient mixed standard working solution into a high performance liquid chromatography-mass spectrometry instrument to determine the (meth)acrylic acid compounds to be tested and their peak areas. Plot a standard working curve with concentration as the abscissa and peak area of ​​(meth)acrylic acid compounds as the ordinate, and calculate the standard curve equation.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] This invention employs an ultrasonic extraction pretreatment-high performance liquid chromatography-mass spectrometry (HPLC-MS) method to simultaneously and accurately detect acrylic acid (AA) and methacrylic acid (MA) in textiles. Within a concentration range of 0.5 mg / L to 100 mg / L, the linear correlation coefficient is above 0.993. The detection limit for acrylic acid is 1.80 mg / kg, and the detection limit for methacrylic acid is 0.77 mg / kg. The quantitation limit for acrylic acid is 5.30 mg / kg, and the quantitation limit for methacrylic acid is 2.40 mg / kg. The spiked recoveries range from 81.74% to 99.10%, and the relative standard deviations (RSDs) range from 1.04% to 2.89%. This method effectively separates and detects (meth)acrylic acid, exhibits high sensitivity, is simple to operate, and meets practical needs. Attached Figure Description

[0027] Figure 1 a-1d is a graph showing the extraction effect of different extraction reagents on spiked textiles and actual positive samples of different materials (meth)acrylic acid.

[0028] Figure 2 a-2c is a graph showing the extraction effect of different amounts of extractant on (meth)acrylic acid in spiked textiles of different materials.

[0029] Figure 3 a-3d is a graph showing the extraction effect of different extraction temperatures on spiked textiles of different materials (meth)acrylic acid.

[0030] Figure 4 a-4d is a graph showing the extraction effect of (meth)acrylic acid in spiked textiles of different materials at different extraction times.

[0031] Figure 5 a-5d are graphs showing the extraction effects of different extraction powers on spiked textiles of different materials (meth)acrylic acid.

[0032] Figure 6 These are chromatograms of the detection of acrylic acid and methacrylic acid using different chromatographic columns.

[0033] Figure 7 This is a chromatogram of the detection of acrylic acid and methacrylic acid using ammonium acetate and acetonitrile as mobile phases at different mobile phase ratios.

[0034] Figure 8 This is a chromatogram of the detection of acrylic acid and methacrylic acid using pure water and acetonitrile as mobile phases at different mobile phase ratios.

[0035] Figure 9 This is a chromatogram of the detection of acrylic acid and methacrylic acid using ammonium acetate and methanol as mobile phases at different mobile phase ratios.

[0036] Figure 10 This is a chromatogram of the detection of acrylic acid and methacrylic acid using pure water and methanol as mobile phases at different mobile phase ratios.

[0037] Figure 11 This is a chromatogram of mobile phases with different ammonium acetate contents for the detection of acrylic acid and methacrylic acid.

[0038] Figure 12 This is a chromatogram of the detection of acrylic acid and methacrylic acid by mobile phases of different ammonia concentrations.

[0039] Figure 13 This is a graph showing the effect of different flow rates on the detection of acrylic acid and methacrylic acid.

[0040] Figure 14 This is a graph showing the effect of different fragmentation voltages on the detection of acrylic acid and methacrylic acid.

[0041] Figure 15 This is a chromatogram of HPLC-MS for the detection of acrylic acid and methacrylic acid. Detailed Implementation

[0042] The technical solution of the present invention will be clearly and thoroughly described below with reference to the accompanying drawings and specific embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Other embodiments obtained by those skilled in the art without creative effort should be covered within the protection scope of the present invention.

[0043] The materials used in the following examples are all commercially available products. Unless otherwise specified, the experimental conditions were performed according to the manufacturer's recommendations or conventional experimental conditions in the field.

[0044] (1) Preparation of standard stock solutions and mixed standard working solutions:

[0045] Accurately weigh 0.2 g each of acrylic acid (AA) and methacrylic acid (MA) standards, dissolve them separately in methanol, and then transfer them to 10 mL volumetric flasks and dilute to volume to obtain a 2000 mg / L standard stock solution. Store this stock solution in a brown sample bottle protected from light. According to the experimental design requirements, pipette equal volumes of each (meth)acrylic acid standard stock solution into the same brown volumetric flask protected from light, and dilute to volume with methanol to prepare the required concentration. This is the mixed standard working solution, which should be prepared fresh before use.

[0046] (2) Preparation of spiked textiles:

[0047] Accurately weigh 1.00g of blank lining fabrics of different materials such as cotton, wool, polyester, and nylon, cut them into pieces smaller than 0.5cm × 0.5cm, place them in a 50mL sealable screw-top sample bottle, add different volumes of 100mg / L mixed standard working solution to the cut blank lining fabric, seal the bottle tightly, and let it stand for 15 minutes.

[0048] Example 1: Optimization of Experimental Conditions

[0049] 1.1 Selection of Extractant

[0050] Extraction experiments were conducted using extractants with different solubilities. Six 1.0g samples of spiked textiles of different materials (cotton, wool, and polyester) were weighed, with each spiked fabric containing 10mg / kg of mixed standard working solution. These samples were placed in 50mL screw-top sample vials, and 10mL of each extractant (methanol, acetonitrile, ethyl acetate, n-hexane, methyl tert-butyl ether, and N,N-dimethylformamide) were added for extraction. After sonication at 50℃ for 40min, 1mL of the extract was filtered through a filtration filter and placed in a 2mL injection vial. The results were analyzed by HPLC-MS, and three parallel experiments were performed. The average value was calculated. Simultaneously, 100µL of a 100mg / L mixed standard stock solution was added to another screw-top sample vial, along with the same volume of extractant but without a backing fabric, to form a control experiment, and the extraction rate was calculated.

[0051] Meanwhile, a polyacrylic waterproof coated fabric was selected as the actual positive sample for simultaneous extraction experiments: 1g of the actual positive sample was weighed, cut into small fragments of 0.5cm×0.5cm, placed in a 50mL sealable screw-top sample bottle, the above-mentioned extractant was added, and extraction was carried out under the same extraction conditions. After extraction, the peak area was detected by HPLC-MS, and three sets of parallel experiments were carried out. The average value of the results was calculated.

[0052] The extraction effects of different extractants on (meth)acrylic acid in spiked textiles and actual positive samples of different materials, such as... Figure 1 As shown in a-1d, where, Figure 1'a' represents cotton fabric. Figure 1 b represents wool fabric. Figure 1 c represents polyester fiber. Figure 1 d represents the actual positive sample.

[0053] from Figure 1 As can be seen from a-1c, hexane has the lowest extraction rate, followed by methyl tert-butyl ether and ethyl acetate. The extraction efficiency of N,N-dimethylformamide is not much different from that of acetonitrile. However, after extraction with N,N-dimethylformamide, more other non-target components are extracted by the extractant. When the extractant is filtered through a filter, the filter port is easily blocked, which affects the experimental results. The extraction effect is the best when methanol is used as the extractant.

[0054] At the same time Figure 1 As can be seen from d, in the actual detection of positive samples, the peak area of ​​methanol is still the highest. Considering the low price of methanol and its polarity similar to that of acrylic acid, methanol is chosen as the extraction reagent.

[0055] 1.2 Confirmation of Extractant Dosage

[0056] Weigh 1.0g of each of four spiked textile samples of different materials (cotton, wool, and polyester), with a mixed standard working solution concentration of 10mg / kg on each spiked fabric. Place each sample in a 50mL screw-top sample bottle, and add (5, 10, 15, and 20)mL of chromatographic grade methanol, respectively. Sonicate at 50℃ for 40min. After sonication, measure 1mL of the extract, filter through a filtration filter, and place it in a 2mL injection bottle. Analyze the extract by HPLC-MS. Perform three parallel experiments and calculate the average value. In another screw-top sample bottle, add 100µL of a 100mg / L mixed standard stock solution, and add (5, 10, 15, and 20)mL of extractant without a backing fabric to conduct a control experiment to calculate the extraction rate.

[0057] The extraction effect of different extractant dosages on (meth)acrylic acid in spiked textiles of different materials, such as... Figure 2 As shown in a-2c, where, Figure 2 'a' represents cotton fabric. Figure 2 b represents wool fabric. Figure 2 c represents polyester fiber.

[0058] from Figure 2As shown in a-2c, with the increase of the extractant dosage, the extraction rate exhibits a trend of first increasing and then stabilizing or slightly decreasing. The lowest extraction rate is achieved when the extractant dosage is 5 mL, mainly because the amount of extractant is too small to completely submerge 1.0 g of the test fabric, meaning that the (meth)acrylic acid on the fabric cannot be completely extracted. When the extractant dosage is 10 mL, 15 mL, and 20 mL, the extraction rate of (meth)acrylic acid is similar. Therefore, the optimal extractant dosage is 10–20 mL.

[0059] 1.3 Confirmation of extraction temperature

[0060] The extraction reagent methanol used in this experiment has a boiling point of 64.7℃, and the temperature in the detection chamber was 25℃. During ultrasonic extraction, the extraction temperature must be lower than the boiling point of the selected extraction reagent. Therefore, the effect of extraction temperature on the extraction results was investigated within the temperature range of 20–60℃.

[0061] Five 1.0g samples of different spiked textile materials (cotton, wool, and polyester) were weighed, with each sample containing 10mg / kg of the mixed standard working solution. These samples were placed in 50mL screw-top sample vials, and 10mL of chromatographic grade methanol was added. The samples were then sonicated for 40min at different extraction temperatures (20℃, 30℃, 40℃, 50℃, and 60℃). After sonication, 1mL of the extract was filtered through a filtration filter and placed in a 2mL injection vial for HPLC-MS analysis. Three parallel experiments were performed, and the average value was calculated. In another screw-top sample vial, 100µL of a 100mg / L mixed standard stock solution was added, along with 10mL of extractant without a lining fabric. Control experiments were conducted at different extraction temperatures (20℃, 30℃, 40℃, 50℃, and 60℃) to calculate the extraction rate.

[0062] Simultaneously, a polyacrylic waterproof coated fabric was selected as the actual positive sample for a synchronous extraction experiment: 1g of the actual positive sample was weighed, cut into 0.5cm×0.5cm fragments, placed in a 50mL sealable screw-top sample bottle, and 10mL of chromatographic grade methanol was added. The same extraction method as above was used for extraction at different extraction temperatures (20℃, 30℃, 40℃, 50℃, 60℃). After extraction, the peak area was detected by HPLC-MS. Three parallel experiments were conducted, and the average value of the results was calculated.

[0063] The effects of different extraction temperatures on the extraction of (meth)acrylic acid from spiked textiles and actual positive samples of different materials, such as... Figure 3 As shown in a-3d, where, Figure 3 'a' represents cotton fabric. Figure 3 b represents wool fabric. Figure 3 c represents polyester fiber. Figure 3d represents the actual positive sample.

[0064] from Figure 3 As shown in Figures a-3d, with increasing extraction temperature, intermolecular thermal motion intensifies. Under the action of the extractant, (meth)acrylic acid monomers are extracted from the fabric and enter the extraction solution. The extraction temperature is between 20℃ and 50℃, and the extraction rate and peak area are positively correlated. When the temperature rises to 50℃, the (meth)acrylic acid on the fabric is almost completely extracted, reaching equilibrium. Therefore, the extraction temperature is selected as 40–60℃.

[0065] 1.4 Determination of extraction time

[0066] Five 1.0g samples of different spiked textile materials (cotton, wool, and polyester) were weighed, with each sample containing 10mg / kg of the mixed standard working solution. Each sample was placed in a 50mL screw-top sample bottle, and 10mL of chromatographic grade methanol was added. The samples were then ultrasonically extracted at 50℃ for 25min, 30min, 35min, 40min, and 45min, respectively. After ultrasonication, 1mL of the extract was measured, filtered through a filtration filter, and placed in a 2mL injection bottle. The extract was analyzed by HPLC-MS. Three parallel experiments were performed, and the average value was calculated. Simultaneously, 100µL of a 100mg / L mixed standard stock solution was added to another screw-top sample bottle, along with 10mL of extractant without a lining fabric. The samples were ultrasonically extracted for different times (25min, 30min, 35min, 40min, and 45min) to serve as a control experiment, and the extraction rate was calculated.

[0067] Simultaneously, a polyacrylic waterproof coated fabric was selected as the actual positive sample for a synchronous extraction experiment: 1g of the actual positive sample was weighed, cut into 0.5cm×0.5cm fragments, placed in a 50mL sealable screw-top sample bottle, and 10mL of chromatographic grade methanol was added. The same extraction method as above was used, and ultrasonic extraction was performed at 50℃ for 25min, 30min, 35min, 40min, and 45min. After extraction, the peak area was detected by HPLC-MS. Three parallel experiments were conducted, and the average value of the results was calculated.

[0068] The effects of different extraction times on the extraction of (meth)acrylic acid from spiked textiles and actual positive samples of different materials, such as... Figure 4 As shown in a-4d, where, Figure 4 'a' represents cotton fabric. Figure 4 b represents wool fabric. Figure 4 c represents polyester fiber. Figure 4 d represents the actual positive sample.

[0069] As shown in the figure, the extraction time is positively correlated with the extraction rate and peak area when the extraction time is between 25 and 40 minutes. Within the extraction time range of 40 to 45 minutes, the extraction rate and peak area tend to reach equilibrium with increasing time. Therefore, an extraction time of 40 to 45 minutes is recommended.

[0070] 1.5 Determination of Extraction Power

[0071] Five 1.0g samples of different spiked textile materials (cotton, wool, and polyester) were weighed, with each sample containing 10mg / kg of the mixed standard working solution. These samples were placed in 50mL screw-top sample vials, and 10mL of chromatographic grade methanol was added. The samples were then ultrasonically extracted at 50℃ for 40min using ultrasonic extraction powers of 300W, 350W, 400W, 450W, and 500W. After ultrasonic extraction, 1mL of the extract was filtered through a filtration filter and placed in a 2mL injection vial. The extract was analyzed by HPLC-MS. Three parallel experiments were conducted, and the average value was calculated. Simultaneously, 100µL of a 100mg / L mixed standard stock solution was added to another screw-top sample vial, along with 10mL of extractant. A control experiment was conducted using unlined fabric at different ultrasonic powers (300W, 350W, 400W, 450W, and 500W) to calculate the extraction rate.

[0072] Simultaneously, a polyacrylic waterproof coated fabric was selected as the actual positive sample for a concurrent extraction experiment: 1g of the actual positive sample was weighed, cut into 0.5cm×0.5cm fragments, placed in a 50mL sealable screw-top sample bottle, and 10mL of chromatographic grade methanol was added. The same extraction method as above was used, and ultrasonic extraction was performed at 50℃ for 40min. The ultrasonic extraction powers were 300W, 350W, 400W, 450W, and 500W, respectively. After extraction, the peak area was detected by HPLC-MS. Three parallel experiments were performed, and the average value of the results was calculated.

[0073] The extraction effects of different extraction powers on (meth)acrylic acid in spiked textiles and actual positive samples of different materials, such as... Figure 5 As shown in figures a to 5d, where... Figure 5 'a' represents cotton fabric. Figure 5 b represents wool fabric. Figure 5 c represents polyester fiber. Figure 5 d represents the actual positive sample.

[0074] As shown in the figure, when the extraction power is between 300W and 450W, the extraction power is positively correlated with the extraction rate and peak area. Within the extraction power range of 450W-500W, as the extraction power increases, the extraction rate and peak area tend to reach equilibrium with less variation. Therefore, an ultrasonic power of 400-500W should be selected.

[0075] 1.6 Determination of chromatographic column

[0076] The two target components being measured exhibited high structural and polarity similarity; therefore, selecting a suitable chromatographic column is crucial for their separation. This experiment used two columns with significant differences in stationary phase, inner diameter, column length, and film thickness to detect a 100 mg / L mixed standard working solution. Specifically, the columns were: a Proshell 120 Hilic column (stationary phase: polysaccharide derivative) and a ZORBAX Eclipse Plus C18 column (stationary phase: dimethyl silica). The corresponding detection chromatograms... Figure 6 As shown.

[0077] from Figure 6 As can be seen, the Proshell 120Hilic column could not separate the two substances, and the peak obtained by the Proshell 120Hilic column was broad and had a low peak area. The ZORBAX Eclipse Plus C18 column could separate the two substances well, with sharp and symmetrical peaks, good separation, and high response value, which fully met the detection requirements. Therefore, the ZORBAX Eclipse Plus C18 column was used for detection.

[0078] 1.7 Determination of mobile phase and its proportion

[0079] With a defined column in the HPLC-MS instrument, the resolution and peak area of ​​different types of mobile phases and their ratios were investigated based on the polarity of (meth)acrylic acid. Due to the similar chemical properties, strong polarity, early elution time, and similar peak ranges of the two target analytes, this experiment primarily focused on optimizing the mobile phase ratio by selecting a high proportion of aqueous phase and a low proportion of organic phase. Specifically, ammonium acetate and acetonitrile, pure water and acetonitrile, ammonium ethanol and methanol, and pure water and methanol were used as mobile phases, and detection was performed at different mobile phase ratios (100:0, 95:5, 90:10, and 85:15). The resolution and peak area are shown below. Figures 7-10 As shown.

[0080] from Figure 7-8 As can be seen, when the mobile phase is ammonium acetate and acetonitrile, or pure water and acetonitrile, the two substances cannot be separated, and the peak shape is too broad and the response value is too low; for example... Figure 9 As shown, when ammonium acetate and methanol are used as the mobile phase, a ratio of 100:0 provides good resolution, but the peak area is too low. Furthermore, when the mobile phase does not contain an organic phase, the aqueous phase is highly susceptible to microbial growth, resulting in slow filtration and eventually column blockage. Figure 10As shown, when pure water and methanol are used as the mobile phase, the peak area values ​​are more ideal, but the two target substances cannot be separated and the chromatographic peaks show tailing. When the ratio is 90:10, compared with the ratios of 100:0 and 95:5, the peak area resolution decreases and impurities appear at the peak tails.

[0081] Taking all factors into consideration, methanol was chosen as the organic phase, with a water-to-organic phase ratio of 95:5. The aqueous phase was also compounded. Specifically, pure water and ammonium acetate were mixed, with a small amount of ammonia added to adjust the pH, improve the response value and resolution, and reduce peak tailing.

[0082] To further investigate the effects of different ammonium acetate concentrations on resolution and peak area in liquid chromatography detection, specifically, with an aqueous phase to organic phase (methanol) ratio of 95:5, an ammonia content of 0.5 mL / L, and ammonium acetate concentrations of 0, 0.005 mol / L, 0.01 mol / L, and 0.02 mol / L, acrylic acid and methacrylic acid were detected by HPLC-MS. The detection results are as follows: Figure 11 .

[0083] from Figure 11 It can be seen that when the ammonium acetate content is 0.005 mol / L, the chromatographic peaks are well separated, the two target substances can be completely separated, and they have good peak area values.

[0084] The effects of different ammonia concentrations on resolution and peak area in HPLC detection were further investigated. Specifically, with an aqueous phase to organic phase (methanol) ratio of 95:5, ammonium acetate concentration of 0.005 mol / L, and ammonia concentrations of 0, 1 mL / L, and 2 mL / L, the chromatograms for the detection of acrylic acid and methacrylic acid by HPLC-MS are shown below. Figure 12 As shown.

[0085] The addition of ammonia can reduce the contact between sample molecules and silanol groups in the stationary phase, and decrease the interaction force between polar groups and silanol groups, thereby improving peak shape and reducing tailing. Figure 12 It can be seen that when no ammonia is added, the two substances are slightly separated, but the separation degree of acrylic acid and methacrylic acid is very low, the response value is not high, and the peak of methacrylic acid has obvious tailing. When 2 mL / L ammonia is added, the pH is 10.12, and when 1 mL / L ammonia is added, the pH is 9.8. Compared with adding 2 mL / L ammonia, the peak shape of adding 1 mL / L ammonia is symmetrical and sharp, and there is a better response value. Therefore, it is better to add 1 mL / L ammonia.

[0086] 1.8 Determination of Flow Velocity

[0087] In liquid chromatography, flow rate is one of the most important parameters. If the flow rate is too fast, the residence time of the sample in the chromatographic column will be too short, resulting in some target components not being separated. If the flow rate is too slow, the separation time will be prolonged, affecting the efficiency of the experiment.

[0088] To select the optimal flow rate for HPLC-MS detection and analysis, this experiment investigated the effect of flow rates in the range of 0.1–0.5 mL / min on the HPLC separation of acrylic acid and methacrylic acid. The detection results are as follows: Figure 13 As shown.

[0089] from Figure 13 It can be seen that when the flow rate is 0.1 mL / min, the longer residence time of the sample in the chromatographic column results in higher ionization efficiency and better response value.

[0090] 1.9 Determination of Fragmentation Voltage

[0091] To obtain optimal experimental results, this experiment investigated the effect of several different breaking voltages between 40V and 110V on the determination of 20mg / L (meth)acrylic acid mixed standard working solution. The test results are as follows: Figure 14 As shown.

[0092] As shown in the figure, acrylic acid and methacrylic acid exhibit similar trends: the peak area gradually increases with increasing fragmentation voltage. After reaching a certain peak value, the peak area gradually decreases with further increases in fragmentation voltage. This is mainly because increasing the voltage increases the transmission efficiency of the precursor ions, leading to more precursor ions entering the collision cell. However, when the voltage exceeds a certain value, the high voltage can cause the precursor ions to ionize, thereby reducing the response value. Therefore, the optimal fragmentation voltage is 40V–70V.

[0093] 1.10 Retention time and characteristic ions

[0094] The optimal instrument conditions optimized in Examples 1.6-1.9 above were used to detect the 20 mg / L mixed standard working solution of (meth)acrylic acid. The retention times and characteristic ions of the two (meth)acrylic acid target compounds, as well as the corresponding chromatograms, are shown in Tables 2 and 3, respectively. Figure 15 As shown, the optimal instrument conditions are as follows:

[0095] A ZORBAX Eclipse Plus C18 column was selected, with ultrapure water and methanol in a ratio of 95:5 as the mobile phase. 0.005 mol / L ammonium acetate and 1 mL / L ammonia were added. The response value and resolution were adjusted, the carrier gas flow rate was 0.1 mL / min, and the ion source was an ion source with Jet Stream electrospray ionization (ESI) and the fragmentation voltage was set to 50 V.

[0096] Table 2 Retention times and characteristic ions of two (meth)acrylic acid compounds

[0097]

[0098] Example 2, Methodological Validation

[0099] 2.1 Linearity and Detection Limit

[0100] 1 mL of a mixed standard working solution of (meth)acrylic acid with concentration gradients of 0.5 mg / L, 1 mg / L, 2 mg / L, 5 mg / L, and 10 mg / L was respectively pipetted into 2 mL injection vials and then injected into a high-performance liquid chromatography-mass spectrometry (HPLC-MS) instrument for detection. The resulting HPLC-MS chromatograms were plotted, and a standard curve was constructed with sample concentration on the x-axis and peak area on the y-axis. The HPLC-MS testing conditions were as follows: a ZORBAX Eclipse Plus C18 column was selected; the mobile phase was ultrapure water and methanol in a ratio of 95:5; 0.005 mol / L ammonium acetate and 1 mL / L ammonia were added; the response value and resolution were adjusted; the carrier gas flow rate was 0.1 mL / min; the ion source was an ion source with Jet Stream electrospray ionization (ESI) and the fragmentation voltage was set to 50 V. The linear range, linear equation, and correlation coefficient of acrylic acid and methacrylic acid are shown in Table 3 below.

[0101] Table 3. Linear range, linear equation, and correlation coefficient of acrylic acid and methacrylic acid.

[0102]

[0103] As shown in Table 3, the method exhibits good linearity in the concentration range of 0.005 mg / L to 0.01 mg / L. The linear correlation coefficients for both acrylic acid and methacrylic acid are above 0.9993, which meets the requirements of practical testing.

[0104] Following the above method, the limits of detection and limits of quantitation for acrylic acid and methacrylic acid were determined through low-concentration spiking tests, as shown in Table 4 below:

[0105] Table 4. Detection limits and quantitation limits of acrylic acid and methacrylic acid.

[0106]

[0107] As shown in Table 4, the detection limit for acrylic acid by HPLC-MS is 1.80 mg / kg, and the detection limit for methacrylic acid is 0.77 mg / kg. The quantitation limit for acrylic acid is 5.30 mg / kg, and the quantitation limit for methacrylic acid is 2.40 mg / kg, which meets the requirements for routine testing.

[0108] 2.2 Recovery rate and precision

[0109] To demonstrate the universality of the determination method of this invention, based on four different textile materials (cotton fabric, wool fabric, polyester fiber, and polyamide fiber), three different spiking amounts (5 mg / kg, 500 mg / kg, and 1000 mg / kg) within the range of 5–1000 mg / kg were selected to calculate the spiked recovery rate and relative standard deviation, and the results are shown in Table 5 below.

[0110] Table 5. Recovery and relative standard deviation of (meth)acrylic acid by HPLC-MS (n=6)

[0111]

[0112] As shown in Table 5, under the three spiking levels, the spiked recoveries of (meth)acrylic acid in cotton fabrics ranged from 81.74% to 96.43%, in wool fabrics from 82.15% to 96.35%, in polyester fibers from 93.26% to 98.65%, and in polyamide fibers from 93.58% to 99.10%.

[0113] The relative standard deviation of the method for detecting (meth)acrylic acid in different textiles was less than 2.89%, indicating that the ultrasonic extraction-high performance liquid chromatography-mass spectrometry method has good reproducibility and accuracy for the detection of (meth)acrylic acid in textiles.

[0114] Application Example 1

[0115] The determination of (meth)acrylic acid compounds in a positive sample includes the following steps:

[0116] (1) Accurately weigh the positive sample and place it in the reactor. Add the extraction solvent methanol. The mass-volume ratio of the positive sample to the extraction solvent is 1g:10mL. Place it in an ultrasonic generator at 40℃ with a working frequency of 400W and extract for 30min to obtain the test solution.

[0117] (2) The standard curve equation and HPLC-MS test conditions are the same as in Example 2.1, Linearity and Detection Limit;

[0118] (3) Inject the test solution obtained in step (1) into HPLC-MS, measure the two types of (meth)acrylic acid and their peak areas, and calculate the content of the two types of (meth)acrylic acid in the positive sample according to the standard curve equation.

[0119] The positive sample was ultimately found to contain 1.2 mg / kg of methacrylic acid and 46 mg / kg of acrylic acid.

[0120] The above description is only a preferred embodiment of the present invention and does not limit the scope of protection of the present invention. All equivalent substitutions or modifications made based on the inventive concept of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for determining (meth)acrylic acid compounds in textiles, characterized in that, The steps include the following: (1) Accurately weigh the textile sample to be tested, place it in a reactor, add an extractant and perform ultrasonic extraction to obtain the test solution; the extractant is methanol; (2) Inject the test solution into a high performance liquid chromatography-mass spectrometry instrument to determine the (meth)acrylic acid compounds and their peak areas, and calculate the content of (meth)acrylic acid compounds in the textile sample to be tested according to the standard curve equation; The (meth)acrylic acid compounds include acrylic acid and methacrylic acid; The testing conditions for high performance liquid chromatography-mass spectrometry (HPLC-MS) are as follows: A ZORBAX Eclipse Plus C18 column was selected, with ultrapure water and methanol in a ratio of 95:5 as the mobile phase. 0.005~0.01 mol / L ammonium acetate and 1~2 mL / L ammonia water were added. The response value and resolution were adjusted, and the carrier gas flow rate was 0.1 mL / min. The retention times and characteristic ions of the (meth)acrylic acid compounds are shown in the table below: The ion source is an ion source with Jet Stream electrospray, and the fragmentation voltage is 40~70V.

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

3. The method for determining (meth)acrylic acid compounds in textiles according to claim 1, characterized in that, In step (1), the ultrasonic extraction conditions are: extraction temperature of 40~60℃; extraction time of 40~45min; and extraction power of 400~500W.

4. The method for determining (meth)acrylic acid compounds in textiles according to claim 1, characterized in that, In step (2), the process of creating the standard curve equation is as follows: S1: Accurately weigh an appropriate amount of the (meth)acrylic acid compound standard to be tested, dissolve it in methanol, 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 high performance liquid chromatography-mass spectrometry instrument to determine the (meth)acrylic acid compounds to be tested and their peak areas. Plot a standard working curve with concentration as the abscissa and peak area of ​​(meth)acrylic acid compounds as the ordinate, and calculate the standard curve equation.

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