Method and device for determining the residual amount of antioxidant in rubber based on GC-FID method

Abstract

The present invention provides a method and device for determining the residual amount of antioxidant in rubber based on the GC-FID method. The method for determining the residual amount of antioxidant in rubber based on the GC-FID method comprises: obtaining a rubber sample; decomposing the rubber sample to obtain sample crumbs; soaking the sample crumbs in a first solvent for a set time, and performing ultrasonic extraction treatment to obtain an extraction mixture; heating the extraction mixture until the first solvent is completely evaporated, dissolving the residue in a second solvent to obtain a solution to be tested; using the GC-FID method to test the solution to be tested to obtain the residual amount of antioxidant in the rubber sample. This method has the advantages of being simple, rapid, accurate and sensitive, solves the problem of inconvenience in detecting the content of the existing antioxidant 4020, and can achieve the purpose of facilitating food safety testing.

Description

Technical Field

[0001] The invention belongs to the technical field of food safety detection and analysis, and particularly relates to a method and a device for determining the amount of antioxidant residue in rubber based on a GC-FID method. Background Art

[0002] At present, there are two main methods for the detection of antioxidant 4020. One is to use gas chromatography-tandem mass spectrometry for detection according to the Chinese national standard GB / T33078-2016 / ISO 10638:2010 "Determination of rubber antioxidants by gas chromatography-mass spectrometry"; the other is to use gas chromatography for detection according to the "Rubber Antioxidant 4020 Brand Product Quality Industry Self-Discipline Standard" formulated by the China Rubber Industry Association. However, the above two methods can only perform general qualitative or simple semi-quantitative detection, but not quantitative detection. Moreover, when detecting antioxidant 4020 (such as antioxidant 4020 in rubber milk tubes), the pre-treatment method of pyrolysis or solvent extraction used requires the use of special instruments or extractors, heat sources and other equipment, which has problems such as complex operation, long time consumption, poor method sensitivity and quantitative accuracy. Summary of the invention

[0003] In view of the above problems, the present invention is proposed to provide a method and device for determining the residual amount of antioxidant in rubber based on GC-FID method, which can overcome the above problems or at least partially solve the above problems. It can solve the problem of inconvenience in detecting the content of the existing antioxidant 4020 and achieve the purpose of facilitating food safety testing.

[0004] Specifically, the present invention provides a method for determining the amount of antioxidant residue in rubber based on the GC-FID method, comprising:

[0005] Obtaining rubber samples;

[0006] decomposing the rubber sample to obtain sample crumbs;

[0007] Soaking the sample debris in a first solvent for a set time, and performing ultrasonic extraction treatment to obtain an extraction mixture;

[0008] heating the extraction mixture until the first solvent is completely evaporated, and dissolving the residue in a second solvent to obtain a solution to be tested;

[0009] The solution to be tested is tested by GC-FID method to obtain the residual amount of the antioxidant in the rubber sample.

[0010] The present invention also provides a device for determining the amount of antioxidant residue in rubber based on the GC-FID method, comprising:

[0011] A cryogenic grinding device, wherein the cryogenic grinding device is configured to perform cryogenic freezing and grinding treatment on the rubber sample;

[0012] A pre-treatment device, wherein the pre-treatment device is configured to perform ultrasonic extraction and solvent replacement on the ground rubber sample to obtain a solution to be tested;

[0013] A detection device is configured to detect the solution to be detected by using a GC-FID method.

[0014] Optionally, the pre-processing device includes:

[0015] A device body, wherein a working chamber, a first solvent chamber, and a second solvent chamber are formed in the device body, wherein the first solvent chamber and the second solvent chamber are located at the top of the working chamber, and a first liquid adding channel and an exhaust channel with controlled opening are connected between the first solvent chamber and the working chamber, a second liquid adding channel with controlled opening is connected between the second solvent chamber and the working chamber, and a liquid discharge channel with controlled opening is formed at the bottom of the working chamber;

[0016] A heating device, the heating device is arranged on the working chamber and is used to heat the solution in the working chamber;

[0017] A water phase filter membrane is arranged in the drainage channel and is used for filtering the solution to be tested.

[0018] Optionally, the device body includes:

[0019] A housing, the housing being box-shaped and having a gripping portion formed on the surface for hand gripping;

[0020] A working liner, which is detachably mounted in the shell and forms the working chamber therein;

[0021] A first solvent liner, which is disposed on the top of the working liner and is detachably connected to the shell and forms the first solvent cavity therein;

[0022] A second solvent liner is disposed on the top of the working liner and is detachably connected to the shell, and forms the second solvent cavity therein.

[0023] Optionally, a funnel-shaped funnel portion is formed at the bottom of the first solvent chamber, and the first liquid adding channel is formed at the lowest point of the funnel portion, and the exhaust channel is formed at the highest point of the funnel portion.

[0024] Optionally, electrically controlled switch valves are provided in the first liquid adding channel and the second liquid adding channel, and a waterproof and breathable membrane is provided in the exhaust channel.

[0025] Optionally, the working inner tank is in the shape of a sleeve opening upward, and the first solvent inner tank and the second solvent inner tank are integrally formed together to form a solvent assembly. The solvent assembly is slidingly sealed and arranged in the working inner tank to form a piston-cylinder mechanism, and a first magnetic sheet of permanent magnetic material is arranged on the top of the solvent assembly. The first magnetic sheet is oppositely arranged to a second magnetic sheet of electromagnetic material connected to the shell, and is used to press the solvent assembly downward under the repulsive force of the second magnetic sheet and the first magnetic sheet to press the solution to be tested out of the working chamber.

[0026] Optionally, the bottom of the working chamber forms a centered and truncated conical cavity bottom, and a sleeve-shaped pressurizing sleeve is formed on the conical cavity bottom and is coaxially arranged in the working chamber. A pressurizing hole inclined downward from the inside to the outside is formed on the sleeve wall of the pressurizing sleeve, and a stirring paddle rotatably connected to the conical cavity bottom is coaxially arranged in the pressurizing sleeve for stirring in the pressurizing sleeve to form a downward liquid flow.

[0027] Optionally, a confluence chamber is formed in the main body of the device and is spaced below the working chamber. A stirring motor connected to below the stirring paddle is arranged between the confluence chamber and the working chamber, and at least two drainage channels connecting the confluence chamber and the working chamber are evenly distributed in the circumferential direction around the stirring motor.

[0028] Optionally, the outlet at the lower end of the first liquid adding channel and the outlet at the lower end of the second liquid adding channel are both located directly above the opening at the upper end of the pressurizing sleeve, and the inlet at the lower end of the exhaust channel is located directly above the opening at the upper end of the annulus between the barrel wall of the pressurizing sleeve and the chamber wall of the working chamber.

[0029] In the method for determining the residual amount of antioxidant in rubber based on the GC-FID method of the present invention, since the GC-FID method (gas chromatography-hydrogen flame ionization method) is used, and the pretreatment process of the solution to be tested is simple and easy to operate; therefore, the method has the advantages of being simple, rapid, accurate and sensitive, solves the problem of inconvenience in detecting the content of the existing antioxidant 4020, and can achieve the purpose of facilitating food safety testing.

[0030] In the device for determining the residual amount of antioxidant in rubber based on the GC-FID method of the present invention, the device is a special device dedicated to the above method, which includes a low-temperature grinding device, a pre-treatment device and a detection device, wherein the pre-treatment device can realize the automation of the pre-treatment process of the solution to be detected, making the detection more simple and convenient, thereby saving manpower. In addition, the low-temperature grinding device can be used to realize the low-temperature grinding treatment of the rubber sample, maintain the structural stability of the antioxidant 4020, improve the accuracy of the detection, and increase the recovery rate of this determination method. Therefore, the device of the present invention can solve the problem of the inconvenience of the existing antioxidant 4020 content detection, and achieve the purpose of facilitating food safety detection.

[0031] Based on the following detailed description of specific embodiments of the present invention in conjunction with the accompanying drawings, those skilled in the art will become more aware of the above and other objects, advantages and features of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Hereinafter, some specific embodiments of the present invention will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings:

[0033] Figure 1 is a flow chart of a method for determining the amount of antioxidant residue in rubber based on GC-FID method according to one embodiment of the present invention;

[0034] Figure 2 is a schematic structural diagram of a device for determining the amount of antioxidant residue in rubber based on a GC-FID method according to one embodiment of the present invention;

[0035] Figure 3 is a schematic structural diagram of a pre-treatment device in a device for determining the amount of antioxidant residue in rubber based on a GC-FID method according to one embodiment of the present invention;

[0036] Figure 4 is a schematic structural diagram of a pre-treatment device in a device for determining the amount of antioxidant residue in rubber based on a GC-FID method according to one embodiment of the present invention;

[0037] Figure 5 It is a schematic structural diagram of a pre-treatment device in a device for determining the amount of antioxidant residue in rubber based on a GC-FID method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] Refer to the following Figures 1 to 5To describe the method and device for determining the amount of antioxidant residue in rubber based on the GC-FID method according to an embodiment of the present invention. In the description of this embodiment, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features, that is, include one or more of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. When a feature "includes or contains" one or some of the features it covers, unless otherwise specifically described, this indicates that other features are not excluded and may further include other features.

[0039] Unless otherwise clearly defined and limited, the terms "set", "install", "connect", "connect", "fix", "couple" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. A person skilled in the art should be able to understand the specific meanings of the above terms in the present invention according to the specific circumstances.

[0040] In addition, in the description of this embodiment, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. That is, in the description of this embodiment, the first feature being "above", "above", and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature being "below", "below", or "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0041] In the description of the present embodiment, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0042] Figure 1This is a flow chart of the method for determining the residual amount of antioxidant in rubber based on the GC-FID method. Figure 1 As shown, the embodiment of the present invention provides a method for determining the residual amount of antioxidant in rubber based on the GC-FID method, and the method specifically comprises the following steps:

[0043] Step S1, obtaining a rubber sample.

[0044] Step S2, decomposing the rubber sample to obtain sample crumbs.

[0045] Step S3, soaking the sample debris in the first solvent for a set time, and performing ultrasonic extraction treatment to obtain an extraction mixture.

[0046] Step S4, heating the extraction mixture until the first solvent is completely evaporated, and then dissolving the residue in a second solvent to obtain a solution to be tested.

[0047] Specifically, the above steps S3 and S4 are pre-treatment processes; through the pre-treatment process, the solution to be tested can be prepared.

[0048] Step S5, using GC-FID method to detect the solution to be tested to obtain the residual amount of the antioxidant in the rubber sample.

[0049] Specifically, GC-FID refers to gas chromatography-flame ionization detector. GC-FID method refers to gas chromatography-hydrogen flame ionization method. Before the method for measuring the residual amount of antioxidant in rubber based on GC-FID method of the present invention is implemented, it is necessary to first make a standard working curve, specifically, by preparing antioxidant 4020 standard working solutions with different concentration gradients, using GC-FID method to detect, external standard method quantitative, drawing a standard curve of peak area-concentration, and obtaining a linear equation. In the present embodiment, the process of the above-mentioned step S5 is: adopting GC-FID method to detect the solution to be tested obtained in step S4, specifically, according to the peak area of ​​antioxidant 4020 in the solution to be tested determined by GC-FID, the residual amount of antioxidant 4020 in the rubber sample is calculated by the above-mentioned linear equation.

[0050] The method of the present invention makes up for the current scarcity of existing detection methods for antioxidant 4020. On the one hand, the method of the present invention has a short detection time, high sensitivity, and greatly reduced detection limit and quantitative limit; using GC-FID as a detection means, it has the advantages of being fast, accurate, sensitive and reproducible, and can achieve quantitative detection. On the other hand, compared with the pre-treatment methods of pyrolysis or solvent extraction used in the prior art, the pre-treatment process of the solution to be tested in the present invention is simpler and easier to operate.

[0051] Therefore, the method of the present invention solves the problem of inconvenience in detecting the content of antioxidant 4020 in the prior art, achieves the purpose of facilitating food safety testing, and can provide technical support in detection and analysis for the safety assessment of antioxidant 4020 in food contact materials and products.

[0052] In some optional embodiments of the present invention, the specific steps of step S2 include: grinding the rubber sample using a low temperature grinding device to decompose the rubber sample and obtain sample crumbs. In some alternative embodiments of the present invention, the specific steps of step S2 include: grinding the rubber sample using a normal temperature grinding device to decompose the rubber sample and obtain sample crumbs.

[0053] In this embodiment, through the above-mentioned settings, low-temperature grinding treatment of the rubber sample can be achieved, the structural stability of the antioxidant 4020 is maintained, the accuracy of the detection is improved, and the recovery rate of this determination method is increased.

[0054] Preferably, the cryogenic grinding device is a KOSCONN 8610M ultra-low temperature grinder, the frequency of the cryogenic grinding device is 6-16 Hz, the power is 390 W, and the grinding time is 2 min.

[0055] Further preferably, in step S2, the rubber sample is first cut into blocks and then ground. The above arrangement can save grinding time and avoid the rubber sample temperature being too high due to the grinding process, thereby further maintaining the structural stability of the antioxidant 4020 and further improving the accuracy of the detection.

[0056] In some optional embodiments of the present invention, in step S3, the first solvent is acetonitrile solvent, the set time is 10 minutes, and the extraction mixture is a mixture of acetonitrile solvent and sample debris.

[0057] In some optional embodiments of the present invention, in step S4, the second solvent is an ethanol solvent.

[0058] In the specific process of step S4: the first solvent in the extraction mixture is evaporated by heating, and the evaporated first solvent is collected; after the evaporation is completed, the second solvent is added to the residue, and mixed and stirred to make the residue fully dissolved in the second solvent to obtain a solution to be tested.

[0059] Figure 2 This is a schematic diagram of the device for determining the amount of antioxidant residue in rubber based on the GC-FID method. Figure 2 As shown, and refer to Figures 3 to 5The embodiment of the present invention also provides a device for determining the residual amount of antioxidant in rubber based on the GC-FID method. The device is a special device dedicated to the above method, which includes a low-temperature grinding device, a pretreatment device 100 and a detection device 200.

[0060] The cryogenic grinding device is configured to perform cryogenic freezing and grinding treatment on the rubber sample. The pre-treatment device 100 is configured to perform ultrasonic extraction and solvent replacement on the ground rubber sample to obtain a solution to be tested. The detection device 200 is configured to detect the solution to be tested using a GC-FID method.

[0061] The working process of the device for determining the residual amount of antioxidant in rubber based on the GC-FID method is as follows: a rubber sample is subjected to cryogenic grinding treatment using a cryogenic grinding device to obtain sample debris; the sample debris, a first solvent, and a second solvent are then added to a pretreatment device 100, in which the sample debris and the first solvent are first mixed and ultrasonically extracted to obtain an extraction mixture, and then the first solvent in the extraction mixture is replaced with the second solvent to obtain a solution to be tested; and the solution to be tested is then added to a detection device 200 for detection.

[0062] In the present embodiment, the device for measuring the residual amount of antioxidant in rubber based on GC-FID method of the present invention comprises a low temperature grinding device, a pre-treatment device 100 and a detection device 200, wherein the pre-treatment device 100 can realize the automation of the pre-treatment process of the solution to be detected, making the detection more simple and convenient, thereby saving manpower. In addition, the low temperature grinding device can be used to realize the low temperature grinding treatment of the rubber sample, maintain the structural stability of the antioxidant 4020, improve the accuracy of the detection, and increase the recovery rate of this determination method. Therefore, the device of the present invention can solve the problem of the inconvenience of the existing antioxidant 4020 content detection, and achieve the purpose of being convenient for food safety detection.

[0063] like Figure 3 and Figure 4 As shown, in some optional embodiments of the present invention, the pre-treatment device 100 includes a device body, a heating device 120 and an aqueous phase filter membrane.

[0064] The main body of the device is formed with a working chamber 113, a first solvent chamber 111, and a second solvent chamber 112, wherein the first solvent chamber 111 and the second solvent chamber 112 are located at the top of the working chamber 113, and a first liquid adding channel 1111 and an exhaust channel 1112 with controlled opening are connected between the first solvent chamber 111 and the working chamber 113, a second liquid adding channel 1121 with controlled opening is connected between the second solvent chamber 112 and the working chamber 113, and a liquid discharge channel 1131 with controlled opening is formed at the bottom of the working chamber 113. The heating device 120 is arranged on the working chamber 113, and is used to heat the solution in the working chamber 113. The aqueous phase filter membrane is arranged in the liquid discharge channel 1131, and is used to filter the solution to be tested.

[0065] In this embodiment, the use process of the pretreatment device 100 is: first, add the first solvent to the first solvent chamber 111, add the second solvent to the second solvent chamber 112, and add sample debris to the working chamber 113; then, the first solvent is added to the working chamber 113 through the first liquid addition channel 1111, and after a set time, the heating device 120 heats the working chamber 113, and the first solvent is evaporated and enters the first solvent chamber 111 through the exhaust channel 1112; then, the second solvent is added to the working chamber 113 through the second liquid addition channel 1121 to obtain a solution to be tested, and the solution to be tested is filtered through the aqueous phase filter membrane in the discharge channel 1131 and then discharged to the outside of the working chamber 113.

[0066] like Figure 3 and Figure 4 As shown, in some optional embodiments of the present invention, the device body includes: a shell 110 , a working liner 153 , a first solvent liner 151 and a second solvent liner 152 .

[0067] The housing 110 is box-shaped and has a gripping portion 1101 formed on the surface for hand gripping. The working liner 153 is detachably mounted in the housing 110, and the working chamber 113 is formed therein. The first solvent liner 151 is disposed on the top of the working liner 153 and is detachably connected to the housing 110, and the first solvent chamber 111 is formed therein. The second solvent liner 152 is detachably connected to the housing 110 and the second solvent chamber 112 is formed therein.

[0068] like Figure 3-5 As shown, in some optional embodiments of the present invention, a funnel-shaped funnel portion 1113 is formed at the bottom of the first solvent chamber 111, and the first liquid adding channel 1111 is formed at the lowest point of the funnel portion 1113, and the exhaust channel 1112 is formed at the highest point of the funnel portion 1113.

[0069] In an embodiment, the speed of adding liquid into the working chamber 113 can be increased by providing the funnel portion 1113 .

[0070] Furthermore, if Figure 3 As shown, a first liquid inlet 1114 is formed at the top of the first solvent chamber 111 for adding the first solvent into the first solvent chamber 111. Figure 4 As shown, a second liquid inlet 1122 is formed at the top of the second solvent chamber 112 for adding the second solvent into the second solvent chamber 112 .

[0071] like Figure 3 and Figure 4 As shown, in some optional embodiments of the present invention, electrically controlled switch valves are provided in the first liquid adding channel 1111 and the second liquid adding channel 1121 , and a waterproof and breathable membrane is provided in the exhaust channel 1112 .

[0072] In this embodiment, by providing an electrically controlled switch valve, automatic liquid addition can be achieved. By providing a waterproof and breathable membrane, it can be ensured that only gas can pass through the exhaust channel 1112.

[0073] like Figure 3-5 As shown, in some optional embodiments of the present invention, the bottom of the working chamber 113 forms a centered and truncated conical cavity bottom 1132, and a sleeve-shaped pressurizing sleeve 131 coaxially arranged in the working chamber 113 is formed on the conical cavity bottom 1132, and a pressurizing hole 132 inclined downward from the inside to the outside is formed on the sleeve wall of the pressurizing sleeve 131, and a stirring paddle 133 rotatably connected to the conical cavity bottom 1132 is coaxially arranged in the pressurizing sleeve 131, which is used for stirring in the pressurizing sleeve 131 to form a downward liquid flow.

[0074] In this embodiment, by providing the pressurizing sleeve 131 and the stirring paddle 133 , the solution in the working chamber 113 can be quickly mixed and evenly mixed, thereby improving the detection efficiency and detection accuracy.

[0075] like Figure 3-5 As shown, in some optional embodiments of the present invention, a confluence chamber 114 is formed in the main body of the device and is spaced below the working chamber 113. A stirring motor 134 connected to below the stirring paddle 133 is arranged between the confluence chamber 114 and the working chamber 113, and at least two drainage channels 1131 connecting the confluence chamber 114 and the working chamber 113 are evenly distributed in the circumferential direction around the stirring motor 134.

[0076] like Figure 3-5As shown, in some optional embodiments of the present invention, the outlet at the lower end of the first liquid adding channel 1111 and the outlet at the lower end of the second liquid adding channel 1121 are both located directly above the opening at the upper end of the pressurizing sleeve 131, and the inlet at the lower end of the exhaust channel 1112 is located directly above the opening at the upper end of the annulus between the barrel wall of the pressurizing sleeve 131 and the chamber wall of the working chamber 113.

[0077] In this embodiment, since the outlet at the lower end of the first liquid adding channel 1111 and the outlet at the lower end of the second liquid adding channel 1121 are both located directly above the opening at the upper end of the pressurizing sleeve 131, when the first solvent or the second solvent is added to the working chamber 113, it can directly enter the pressurizing sleeve 131, thereby further improving the mixing efficiency.

[0078] In some optional embodiments of the present invention, the heating device 120 includes a heating coil, which is wound around the outer circumference of the working liner 153. In some alternative embodiments of the present invention, the heating device includes a heating rod, which is disposed in the heating chamber.

[0079] like Figure 5 As shown, in other optional embodiments of the present invention, the working liner 153 is in the shape of a sleeve opening upward, the first solvent liner 151 and the second solvent liner 152 are integrally formed together to form a solvent assembly, the solvent assembly is slidingly sealed and arranged in the working liner 153 to form a piston-cylinder mechanism, and a first magnetic sheet 141 of permanent magnetic material is arranged on the top of the solvent assembly, and the first magnetic sheet 141 is oppositely arranged to be connected to the shell 110 with a second magnetic sheet 142 of electromagnetic material, which is used for pressing the solvent assembly downward under the repulsive force of the second magnetic sheet 142 and the first magnetic sheet 141 to press the solution to be tested out of the working chamber 113.

[0080] In this embodiment, by providing the first magnetic sheet 141 and the second magnetic sheet 142 , the solution to be tested can be quickly pressed out of the working chamber 113 .

[0081] In some optional embodiments of the present invention, the detection device 200 includes a sample injection device, and the sample injection device has an inlet. The outlet of the liquid discharge channel 1131 is connected to the inlet of the sample injection device.

[0082] Specifically, the outlet of the liquid discharge channel 1131 is connected to the liquid inlet through a pipeline.

[0083] In some optional embodiments of the present invention, a confluence chamber 114 is further formed in the device body, and the inlet of the sampling device is connected to the outlet of the confluence chamber 114 .

[0084] Through the above arrangement, automatic sampling of the detection device 200 can be achieved, thereby further saving manpower and improving detection efficiency.

[0085] At this point, those skilled in the art should recognize that, although multiple exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications that conform to the principles of the present invention can still be directly determined or derived based on the content disclosed in the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and recognized as covering all these other variations or modifications.

Claims

1. A method for determining the residual amount of antioxidant in rubber based on GC-FID method, characterized in that: The method is implemented based on a device for determining the amount of antioxidant residue in rubber; The device for measuring the residual amount of antioxidant in rubber comprises: A cryogenic grinding device, wherein the cryogenic grinding device is configured to perform cryogenic freezing and grinding treatment on the rubber sample; A pre-treatment device, wherein the pre-treatment device is configured to perform ultrasonic extraction and solvent replacement on the ground rubber sample to obtain a solution to be tested; A detection device, wherein the detection device is configured to detect the solution to be detected by a GC-FID method; Wherein, the pre-processing device comprises: A device body, wherein a working chamber, a first solvent chamber, and a second solvent chamber are formed in the device body, wherein the first solvent chamber and the second solvent chamber are located at the top of the working chamber, and a first liquid adding channel and an exhaust channel with controlled opening are connected between the first solvent chamber and the working chamber, a second liquid adding channel with controlled opening is connected between the second solvent chamber and the working chamber, and a liquid discharge channel with controlled opening is formed at the bottom of the working chamber; A heating device, the heating device is arranged on the working chamber and is used to heat the solution in the working chamber; A water phase filter membrane, which is arranged in the drainage channel and is used to filter the solution to be tested; The device body comprises: A housing, the housing being box-shaped and having a gripping portion formed on the surface for hand gripping; A working liner, which is detachably mounted in the shell and forms the working chamber therein; A first solvent liner, which is disposed on the top of the working liner and is detachably connected to the shell and forms the first solvent cavity therein; A second solvent liner, the second solvent liner is detachably connected to the shell and is located on the top of the working liner, and the second solvent cavity is formed therein; The method comprises the following steps: Obtaining rubber samples; First, the rubber sample is cut into blocks, and then the rubber sample is subjected to cryogenic grinding by a cryogenic grinding device to decompose the rubber sample to obtain sample crumbs; wherein the frequency of the cryogenic grinding device is 6-16 Hz, the power is 390 W, and the grinding time is 2 min; Using the pretreatment device, soaking the sample debris in a first solvent for 10 minutes, and performing ultrasonic extraction treatment to obtain an extraction mixture; wherein the first solvent is acetonitrile solvent, and the extraction mixture is a mixture of acetonitrile solvent and sample debris; The pretreatment device is used to heat the extraction mixture until the first solvent is completely evaporated, and then the residue is dissolved in a second solvent to obtain a solution to be tested; wherein the second solvent is an ethanol solvent; By preparing antioxidant standard working solutions with different concentration gradients, using GC-FID method for detection and external standard method for quantification, a standard curve of peak area-concentration was drawn; The solution to be tested is added into the detection device for testing, and the peak area of ​​the antioxidant in the solution to be tested is determined by GC-FID to obtain the residual amount of the antioxidant in the rubber sample.

2. The method according to claim 1, characterized in that: A funnel-shaped funnel portion is formed at the bottom of the first solvent chamber, the first liquid adding channel is formed at the lowest point of the funnel portion, and the exhaust channel is formed at the highest point of the funnel portion.

3. The method according to claim 1, characterized in that: The first liquid adding channel and the second liquid adding channel are both provided with electrically controlled switch valves, and the exhaust channel is provided with a waterproof and breathable membrane.

4. The method according to claim 1, characterized in that: The working inner tank is in the shape of a sleeve opening upward, the first solvent inner tank and the second solvent inner tank are integrally formed together to form a solvent assembly, the solvent assembly is slidingly sealed and arranged in the working inner tank to form a piston-cylinder mechanism, and a first magnetic sheet of permanent magnetic material is arranged on the top of the solvent assembly, and a second magnetic sheet of electromagnetic material connected to the shell is arranged opposite to the first magnetic sheet, which is used to press the solvent assembly downward under the repulsive force of the second magnetic sheet and the first magnetic sheet to press the solution to be tested out of the working chamber.

5. The method according to claim 1, characterized in that The bottom of the working chamber forms a centered and truncated conical cavity bottom, and a sleeve-shaped pressurizing sleeve coaxially arranged in the working chamber is formed on the conical cavity bottom. A pressurizing hole inclined downward from the inside to the outside is formed on the sleeve wall of the pressurizing sleeve, and a stirring paddle rotatably connected to the conical cavity bottom is coaxially arranged in the pressurizing sleeve for stirring in the pressurizing sleeve to form a downward liquid flow.

6. The method according to claim 5, characterized in that A confluence chamber is also formed in the device body and is spaced below the working chamber. A stirring motor connected to below the stirring paddle is arranged between the confluence chamber and the working chamber, and at least two drainage channels connecting between the confluence chamber and the working chamber are evenly distributed in the circumferential direction around the stirring motor.

7. The method according to claim 5, characterized in that The outlet at the lower end of the first liquid adding channel and the outlet at the lower end of the second liquid adding channel are both located directly above the opening at the upper end of the pressurizing sleeve, and the inlet at the lower end of the exhaust channel is located directly above the opening at the upper end of the annulus between the barrel wall of the pressurizing sleeve and the cavity wall of the working chamber.

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