Polymer material analysis device

Abstract

To provide a method for analyzing polymer material in which information on both components contained in a polymer material and components of the polymer material itself may be obtained by a double-shot method.SOLUTION: The method includes closing split introduction means 35 to activate suction means 5, heating a sample to thermally desorb contained constituents, capturing a first analyte component into a first column 31, stopping suction means 5 to vaporize the first analyte component, introducing it into a second column 32, separating it, and detecting it with detection means 41. This method includes opening the split introduction means 35 to activate the suction means 5, pyrolyzing the sample, capturing a second analyte component in the first column 31, stopping the suction means 5 to vaporize the second analyte component, and introducing it into the second column 32, separating it, and detecting it with the detection means 41.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for analyzing polymer materials.

Background Art

[0002] Conventionally, gas chromatography is known as a method for analyzing gas components. As a gas component analyzer (gas chromatograph) used in the gas chromatography, for example, there is known one including heating means for heating a sample to generate a gas component mixture, a separation column connected to the heating means for separating the gas component mixture generated by the heating means into individual components, a thermostat (oven) for housing the separation column, and a detector connected to the separation column for detecting the individual components separated by the separation column.

[0003] In the heating means, the gas component mixture is generated by pyrolyzing or volatilizing the sample, or by heating the sample to thermally desorb the components contained in the sample. As the detector, a mass spectrometry detector (MS) or the like is used.

[0004] When analyzing the composition of a polymer material using the gas component analyzer, for example, first, the polymer material is heated to a temperature of about 300°C to thermally desorb the components contained in the polymer material in a free state to generate a first gas component mixture, the first gas component mixture is introduced into the separation column to be separated into individual gas components, and the separated individual gas components are detected by a detector such as the mass spectrometry detector (MS). Next, after the components contained in the free state are thermally desorbed, the polymer material is instantaneously pyrolyzed at a temperature of about 600°C to generate a second gas component mixture, the second gas component mixture is introduced into the separation column to be separated into individual gas components, and the separated individual gas components are detected by a detector such as the mass spectrometry detector (MS).

[0005] Since the method performs the thermal decomposition following the thermal desorption, it is sometimes called a double-shot method.

[0006] Incidentally, typical polymer materials contain additives such as antioxidants and UV absorbers in amounts of 0.1% or less of the total mass to improve performance. For example, ethylene vinyl acetate copolymer resin contains a phosphorus-based processing stabilizer called Irgafos 168 (tris(2,4-di-tert-butylphenyl) phosphite) as such an additive.

[0007] For quality control purposes, the composition of polymer materials containing the aforementioned additives needs to be analyzed. When the composition of the polymer material is analyzed using the double-shot method, it is considered that information about the components contained in a free state, such as the additives, can be obtained by analyzing the first gas-phase component mixture generated by thermal desorption of the polymer material, and information about the polymer material itself can be obtained by analyzing the second gas-phase component mixture generated by thermal decomposition of the polymer material.

[0008] Furthermore, in the aforementioned gas phase component analyzer, a split introduction means (split vent) is known to be provided at the inlet connecting the heating means and the separation column, which introduces a portion of the gas phase component mixture, for example 1-10%, into the separation column while discharging the remaining 90-99% to the outside (see, for example, Patent Document 1). In this case, the components to be introduced into the separation column The ratio of the gas-phase component mixture to the total amount is called the split ratio, and in the gas-phase component analyzer, this split ratio is usually set to a predetermined fixed value. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2018-66618 [Overview of the Initiative] [Problems that the invention aims to solve]

[0010] When the composition of the polymer material is analyzed by the double-shot method, a smaller split ratio is preferable for analyzing the gaseous component mixture produced by the thermal decomposition of the polymer material itself. However, if the split ratio is reduced, the amount of the gaseous component mixture introduced into the separation column decreases. Therefore, if the first gaseous component mixture produced by the thermal desorption of the polymer material originates from components contained in the polymer material in a free state, and the content of these free components relative to the entire polymer material is small (0.1% by mass or less), sufficient detection intensity cannot be obtained, and there is a problem in that the first gaseous component mixture produced by the thermal desorption of the polymer material cannot be analyzed.

[0011] Therefore, when the first gas-phase component mixture produced by thermal desorption of the polymer material originates from components contained in the polymer material in a free state, and the content of these free components relative to the total polymer material is small (0.1% by mass or less), a larger split ratio is preferable for the analysis of the first gas-phase component mixture produced by thermal desorption. However, if the split ratio is increased, and the second gas-phase component mixture produced by the thermal decomposition of the polymer material contains a large amount of non-analyte components such as solvents, unreacted methylating agents, and silylating agents, the separation column may deteriorate or the detector may malfunction, making it impossible to analyze the gas-phase component mixture produced by the thermal decomposition of the polymer material.

[0012] To solve the aforementioned problem, it is conceivable to change the split ratio of the gas phase component analyzer when analyzing the first gas phase component mixture produced by thermal desorption of the polymer material and when analyzing the second gas phase component mixture produced by thermal decomposition of the polymer material itself.

[0013] However, a drawback of the aforementioned gas phase component analyzer is that the split ratio is usually set to a predetermined fixed value, making it difficult to change.

[0014] The present invention overcomes the aforementioned inconvenience and, when analyzing the composition of a polymer material by double-shot method using the gas-phase component analyzer, provides information on both additives and other components contained in the polymer material in a free state and the components of the polymer material itself, without changing the split ratio of the gas-phase component analyzer. Analyzer The purpose is to provide. [Means for solving the problem]

[0015] The applicant has already filed a patent application (see Japanese Patent Application No. 2020-215423) for a gas-phase component analyzer that can prevent deterioration of the separation column and detector by non-analyte components and can also obtain excellent detection sensitivity. The gas-phase component analyzer described in the aforementioned patent application comprises a heating means for heating a sample to generate a gas-phase component mixture, a first column into which the gas-phase component mixture generated by the heating means is introduced, an inlet connecting the heating means and the first column, a second column which is a separation column connected to the first column via a connecting means, a constant temperature bath housing the first column, the second column and the connecting means, and a detection means for detecting individual gas-phase components separated by the second column, wherein the gas-phase component analyzer comprises a suction means connected to the connecting means and a split vent provided at the inlet which introduces a portion of the gas-phase component mixture generated by the heating means into the first separation column while discharging the remainder to the outside.

[0016] According to the gas phase component analyzer described in the patent application, first, the suction means is activated, and the sample is introduced or injected into the heating means to heat the sample and generate the gas phase component mixture. At this time, the suction means is operated for a predetermined time from the time the sample is introduced or injected. As the suction means is activated, the split vent is not substantially activated, the generated gas phase component mixture is aspirated, and the entire amount of the gas phase component mixture is introduced into the first column through the inlet.

[0017] The gas-phase component mixture contains an analyte with a high boiling point and low volatility, and a non-analyte with a low boiling point and high volatility, such as a solvent. However, since the first column is set to a temperature higher than the boiling point of the non-analyte and lower than the boiling point of the analyte, the non-analyte is not captured by the first column and is further drawn towards the suction means, while the analyte is selectively captured by the first column.

[0018] Here, the first column is connected to the second column via the connecting means, and the suction means is also connected to the connecting means. However, since the second column acts as a flow resistance, the non-analyte components are not introduced into the second column but are drawn into the suction means and released to the outside through the suction means.

[0019] If the non-analytical target component is released to the outside, then, after the predetermined time, the suction means is stopped, and the temperature of the thermostat is raised to a temperature at which the analytical target component can be vaporized. By doing so, the analytical target component captured in the first column is vaporized. Further, when the suction means is stopped, the selective introduction means is activated, and the analytical target component moves in the direction of the connection means by a carrier gas whose flow rate is controlled by the selective introduction means.

[0020] At this time, the suction means is stopped, and the direction of the connection means connected to the suction means is in a closed state. Therefore, the vaporized analytical target component is introduced into the second column by the carrier gas. Since the second column is a separation column, the analytical target component introduced into the second column is separated into individual gas-phase components, and the individual gas-phase components that have passed through the second column can be detected by the detection means.

[0021] When the present inventors perform analysis of a polymer material by the double-shot method, by using the gas-phase component analyzer described in the patent application, without changing the split ratio of the gas-phase component analyzer, they conceived that information on both the components of the polymer material itself and the components contained in the polymer material in a free state such as additives can be obtained, and thus reached the present invention.

[0022] Therefore, in order to achieve the above object, the present invention's Polymer material analysis equipment is A heating means for heating a sample to generate a gaseous component mixture, A first column into which the gaseous component mixture generated by the heating means is introduced, An inlet connecting the heating means and the column of the previous first instance, A suction means, A second column, which is a separation column, is connected to the first column and the suction means respectively via a three-way tube as a connecting means, A constant temperature bath housing the first column, the second column, and the connecting means, A heater for adjusting the temperature of the constant temperature bath, A detection means for detecting individual gas-phase components separated in the second column, The inlet is provided with a divided introduction means which, when closed, introduces all of the gaseous component mixture generated by the heating means into the first column, and when open, introduces a portion of the gaseous component mixture generated by the heating means into the first column while discharging the remainder to the outside, A control device that controls the operation of the heating means, the heater, the suction means, and the divided introduction means, A gas phase component analyzer equipped with, The first column captures a portion of the gas-phase component mixture, and the second column separates the gas-phase components.

[0023] In the method for analyzing polymer materials of the present invention, first, in the gas-phase component analyzer, the dividing introduction means is closed and the suction means is activated, and the polymer material to be used as a sample is heated in the heating means. In this way, components contained in the sample in a free state are thermally desorbed from the sample, and the first gas-phase component mixture is generated.

[0024] In this case, in the polymer material analysis method of the present invention, since the divided introduction means is closed, the generated first gas-phase component mixture is sucked up by the suction means and its entire volume is introduced into the first column through the inlet, and the first analyte component contained in the first gas-phase component mixture is captured in the first column. On the other hand, non-analyte components contained in the first gas-phase component mixture are sucked up by the suction means and discharged to the outside.

[0025] Next, once the first analyte has been captured in the first column, the suction means is stopped, the first column is heated to a temperature at which the first analyte can vaporize, and the vaporized first analyte is introduced into the second column. Since the second column is a separation column, the first analyte introduced into the second column is separated into individual gaseous components, and each separated gaseous component is detected by the detection means.

[0026] The individual gas-phase components constituting the first analyte are, for example, components derived from additives contained in the polymer material in an amount of 0.1% by mass or less of the total, and are very dilute. However, according to the polymer material analysis method of the present invention, as described above, the entire amount of the first gas-phase component mixture generated by thermal desorption is introduced into the first column, and the first analyte contained in the first gas-phase component mixture is concentrated by being captured in the first column. Therefore, when detected by the detection means, sufficient detection intensity can be obtained, and information about the first analyte can be obtained.

[0027] In the polymer material analysis method of the present invention, the dividing introduction means is opened and the suction means is activated, and the sample, after the components contained in a free state have been thermally desorbed, is heated in the heating means to thermally decompose the sample. In this way, the second gas-phase component mixture is generated by the thermal decomposition of the polymer material itself that constitutes the sample.

[0028] In this case, in the polymer material analysis method of the present invention, since the divided introduction means is open, a portion of the generated second gas-phase component mixture is introduced into the first column by the divided introduction means, while the remainder is discharged to the outside. Then, the second gas-phase component mixture introduced into the first column has the second analyte component contained in it captured by the first column, while non-analyte components are sucked up by the suction means and discharged to the outside.

[0029] Next, once the second analyte has been captured in the first column, the suction means is stopped, the first column is heated to a temperature at which the second analyte can vaporize, and the vaporized second analyte is introduced into the second column. Since the second column is a separation column, the second analyte introduced into the second column is separated into individual gaseous components, and each separated gaseous component is detected by the detection means.

[0030] The second gas-phase component mixture generated by the thermal decomposition of the polymer material itself may contain a large amount of non-analyte components such as solvents. However, according to the polymer material analysis method of the present invention, as described above, only a portion of the second gas-phase component mixture generated by the thermal decomposition of the polymer material itself is introduced into the first column by the divided introduction means. Furthermore, of the second gas-phase component mixture introduced into the first column, only the second analyte component contained therein is captured by the first column, while the non-analyte components are aspirated by the suction means and discharged to the outside. As a result, only the second analyte component is introduced into the second column and separated into individual gas-phase components, which can be reliably detected by the detection means, and information on the second analyte component can be obtained.

[0031] Accordingly, according to the polymer material analysis method of the present invention, when analyzing a polymer material by double-shot method using the gas phase component analyzer described in Japanese Patent Application No. 2020-215423, it is possible to obtain information on both the components of additives and other substances contained in the polymer material in a free state and the components of the polymer material itself without changing the split ratio of the gas phase component analyzer. [Brief explanation of the drawing]

[0032] [Figure 1] This is an explanatory cross-sectional view showing an example configuration of a gas-phase component analyzer used in the analytical method for polymer materials of the present invention. [Figure 2] This figure shows an example of analysis of a polymer material using the polymer material analysis method of the present invention. The upper panel shows the total ion chromatogram of the gas-phase component mixture produced by thermal desorption, and the lower panel shows the extracted ion chromatogram of the m / z 647 component in the gas-phase component mixture produced by thermal desorption. [Figure 3] This figure shows an example of analysis of a polymer material using the polymer material analysis method of the present invention, and is a pyrogram of the gas phase component mixture produced by thermal decomposition after thermal desorption in Figure 2. [Figure 4]This figure shows an example of analysis of a polymer material that does not follow the polymer material analysis method of the present invention. The upper panel shows the total ion chromatogram of the gas-phase component mixture produced by thermal desorption, and the lower panel shows the extracted ion chromatogram of the m / z 647 component in the gas-phase component mixture produced by thermal desorption. [Figure 5] This figure shows an example of analysis of a polymer material that does not follow the analytical method of the present invention, and is a pyrogram of the gas phase component mixture produced by thermal decomposition after thermal desorption in Figure 4. [Modes for carrying out the invention]

[0033] Next, embodiments of the present invention will be described in more detail with reference to the attached drawings.

[0034] The polymer material analysis method of this embodiment can be carried out using the gas phase component analyzer 1 shown in Figure 1. The gas phase component analyzer 1 is a gas chromatograph and comprises a heating device 2, a constant temperature bath 3 connected to the heating device 2, and a detection device 4 connected to the constant temperature bath 3.

[0035] The heating device 2 comprises a heating furnace 21 made of a chemically inert hollow cylindrical quartz tube, a heater 22 provided around the heating furnace 21, and a GC inlet 23 into which the tip of the heating furnace 21 is inserted. The heater 22 is controlled by a temperature control device (not shown) to heat the heating furnace 21 under predetermined conditions. The heating furnace 21 is connected to the upper part of the GC inlet 23 by a heated pipe or the like, or it is detachably attached to the upper part of the GC inlet 23 without using such a pipe or the like. Alternatively, the heating furnace 21 may be made of a stainless steel tube with a thin quartz film formed on its inner surface to make it inert, instead of the quartz tube.

[0036] Furthermore, the GC inlet 23 is equipped with a heater (not shown), and this heater is not shown in the same way as heater 22. A temperature control device is used to heat the GC inlet 23 under predetermined conditions. The GC inlet 23 is not shown at the upper end if a heating furnace 21 is not connected to or installed above it. A septum is attached.

[0037] The heating device 2 includes a sample introduction section 24 connected above the heating furnace 21, and a carrier gas conduit 25, which serves as a carrier gas introduction means for introducing carrier gas into the heating furnace 21, is connected to the sample introduction section 24. The other end of the carrier gas conduit 25 is connected to a carrier gas source 27 via a flow rate control device 26. Furthermore, if the heating furnace 21 is not connected to or mounted above the GC inlet 23, the carrier gas conduit 25 is connected to the GC inlet 23.

[0038] As a result, the carrier gas supplied from the carrier gas source 27 is adjusted to a predetermined flow rate by the flow rate control device 26 and introduced into the heating furnace 21 or the GC inlet 23.

[0039] The constant temperature bath 3 houses a pre-column 31 as the first column, a main separation column 32 as the second separation column, and a three-way tube (T-tube) 33 as a connecting means for connecting the pre-column 31 and the main separation column 32. One end of the pre-column 31 is inserted into the GC inlet 23 and faces the front of the heating furnace 21, while the other end is connected to the main separation column 32 via the three-way tube 33. One end of the main separation column 32 is connected to the pre-column 31 via the three-way tube 33, while the other end is connected to a detection means 41, such as a quadrupole mass spectrometer, housed in the detection device 4.

[0040] The three-way tube 33 linearly connects the pre-column 31 and the main separation column 32, while being connected to the exhaust conduit 34 in a direction perpendicular to the connection direction between the pre-column 31 and the main separation column 32. The exhaust conduit 34 is connected to a suction pump 5, such as a vacuum pump, located outside the constant temperature bath 3.

[0041] As the pre-column 31, for example, a stainless steel capillary column with an inner diameter of 0.25 mm, a length of 1 m, and a 0.25 μm thick fixed layer on its inner surface made of a copolymer of diphenylpolysiloxane and dimethylpolysiloxane in a 5:95 (molar ratio) can be used, or a capillary column with an inner diameter of approximately 0.1 to 0.5 mm, a length of 0.5 to 19 m, and coated with various polymers on its inner surface, or a capillary tube with a chemically inert inner surface without polymer coating can be used. Furthermore, as the main separation column 32, for example, a stainless steel capillary column with an inner diameter of 0.25 mm, a length of 30 m, and a 0.25 μm thick fixed layer on its inner surface made of a copolymer of diphenylpolysiloxane and dimethylpolysiloxane in a 5:95 (molar ratio) can be used.

[0042] Furthermore, the pre-column 31 is detachably attached to the GC inlet 23 and the three-way tube 33, allowing the pre-column 31 to be selected according to the analyte.

[0043] As the detection means 41, a mass spectrometry detector (MS) such as the quadrupole mass spectrometry detector, a flame ionization detector (FID), an electron capture detector (ECD), etc. can be used.

[0044] Furthermore, the gas phase component analyzer 1 is equipped with a split vent 35 at the GC inlet 23 as a means for introducing a portion of the gas phase component mixture into the pre-column 31. The split vent 35 can be opened and closed by an on-off valve (not shown), and when open, it introduces a portion of the gas phase component mixture introduced from the pyrolysis furnace 21 or generated at the GC inlet 23 into the pre-column 31, while discharging the remainder to the outside. In the split vent 35, the split ratio, which is the ratio of the component introduced into the pre-column 31 to the total amount of the gas phase component mixture, is set to a predetermined value, for example, 1 / 100.

[0045] Next, we will describe the method for analyzing polymer materials in this embodiment using the gas-phase component analyzer 1 shown in Figure 1.

[0046] The polymer material analysis method of this embodiment is used, for example, when analyzing the composition of a polymer material containing additives such as antioxidants and ultraviolet absorbers in an amount of 0.1% by mass or less of the total, using the double-shot method.

[0047] In the polymer material analysis method of this embodiment, first, the split vent 35 is closed, and a carrier gas such as helium or nitrogen is supplied from the carrier gas source 27 to the heating furnace 21 via the flow rate control device 26 at a flow rate of, for example, 2 ml / min, while the heating furnace 21 is heated to a predetermined temperature, for example, 100°C, by the heater 22. Next, with the suction pump 5 activated, the polymer material contained in the sample cup 6 is introduced into the heating furnace 21 as a sample. Then, for example, the temperature of the heating furnace 21 is raised from 100°C to 380°C at a rate of 20°C / min and held at 380°C for 1 minute, thereby thermally desorbing the additives and other components contained in the polymer material in a free state from the polymer material, and generating a first gas-phase component mixture.

[0048] Furthermore, after the generation of the first gas-phase component mixture, the polymer material is kept in the sample cup 6 and moved to an area unaffected by the heating of the furnace 21.

[0049] In the polymer material analysis method of this embodiment, since the split vent 35 is closed, the generated first gas-phase component mixture is sucked up by the suction pump 5 and its entire volume is introduced into the pre-column 31 via the GC inlet 23. At this time, the pre-column 31 is set to a temperature of, for example, 40°C, and among the components contained in the first gas-phase component mixture, those with a boiling point above 40°C are trapped (captured) in the pre-column 31 as the first target components for analysis. On the other hand, among the components contained in the first gas-phase component mixture, those with a boiling point below 40°C are not targeted for analysis and are sucked up by the suction pump 5 and discharged to the outside.

[0050] Next, once the first analyte is trapped in the pre-column 31, the suction pump 5 is stopped, the split vent 35 is opened, and the carrier gas is supplied to the heating furnace 21 at a flow rate of, for example, 200 ml / min, while the pre-column 31 is heated to a temperature at which the first analyte can vaporize, thereby vaporizing the first analyte. Specifically, the operation of heating the pre-column 31 to a temperature at which the first analyte can vaporize is performed by raising the temperature of the constant temperature bath 3. For example, the temperature of the constant temperature bath 3 is maintained at 40°C for 2 minutes, then the temperature is raised from 40°C to 320°C at a rate of 20°C / min, and held at 320°C for 14 minutes, thereby vaporizing the first analyte, and the vaporized first analyte is introduced into the main separation column 32 via the three-way tube 33. Since the main separation column 32 is a separation column, the first analyte introduced into the main separation column 32 is separated into individual gas-phase components in the main separation column 32, and the separated individual gas-phase components are detected by the detection means 41, thereby obtaining a total ion chromatogram (TIC) of the additives and other components contained in the polymer material in a free state. Here, among the additives and other components, specific components can be identified by separately creating an extracted ion chromatogram (EIC) of the specific component and comparing it with the TIC, or by comparing the TIC with a library such as various databases.

[0051] In the polymer material analysis method of this embodiment, once the analysis of the first target component is completed, with the split vent 35 open, a carrier gas such as helium or nitrogen is supplied from the carrier gas source 27 to the heating furnace 21 via the flow rate control device 26 at a flow rate of, for example, 200 ml / min, while the heating furnace 21 is heated to a predetermined temperature, for example, 600°C, by the heater 22. Next, with the suction pump 5 activated, the polymer material that has been set aside while contained in the sample cup 6 is introduced into the heating furnace 21 as a sample, and the polymer material itself is instantaneously thermally decomposed to generate a second gaseous component mixture.

[0052] In this embodiment of the polymer material analysis method, since the split vent 35 is open, a portion of the generated second gas-phase component mixture is introduced into the pre-column 31 according to a predetermined split ratio through the split vent 35, while the remainder is discharged to the outside.

[0053] At this time, the pre-column 31 is set to a temperature of, for example, 40°C, and components in the second gas-phase component mixture with a boiling point exceeding 40°C are trapped in the pre-column 31 as the second analyte. On the other hand, components in the second gas-phase component mixture with a boiling point of 40°C or lower are not analyte and are sucked out by the suction pump 5 and discharged to the outside. If the second gas-phase component mixture contains a large amount of solvents, etc., since many of these solvents, etc. have a boiling point of 40°C or lower, the majority of them are discharged to the outside as the non-analyte.

[0054] Next, once the second analyte is trapped in the pre-column 31, the suction pump 5 is stopped and the pre-column 31 is heated to a temperature at which the second analyte can vaporize, thereby vaporizing the second analyte. Specifically, the operation of heating the pre-column 31 to a temperature at which the second analyte can vaporize is performed by raising the temperature of the constant temperature bath 3. For example, the temperature of the constant temperature bath 3 is maintained at 40°C for 2 minutes, then the temperature is raised from 40°C to 320°C at a rate of 20°C / min, and held at 320°C for 14 minutes, thereby vaporizing the second analyte, and the vaporized second analyte is introduced into the main separation column 32 via the three-way tube 33. Since the main separation column 32 is a separation column, the second analyte introduced into the main separation column 32 is separated into individual gas-phase components in the main separation column 32, and the separated individual gas-phase components are detected by the detection means 41, thereby obtaining a pyrogram of the components constituting the polymer material itself.

[0055] As a result, according to the polymer material analysis method of this embodiment, when analyzing a polymer material by double-shot method using the gas phase component analyzer 1 shown in Figure 1, it is possible to obtain information on both additives and other components contained in the polymer material in a free state, and the components that constitute the polymer material itself, without changing the split ratio of the gas phase component analyzer 1.

[0056] Examples and comparative examples of the present invention are shown below. [Examples]

[0057] [Example 1] In this example, the composition of ethylene vinyl acetate copolymer resin (EVA) as a polymer material was analyzed using the double-shot method with the gas phase component analyzer 1 shown in Figure 1, in which the split ratio of the split vent 35 is set to 1 / 100. The EVA contains a phosphorus-based processing stabilizer called Irgafos 168 (tris(2,4-di-tert-butylphenyl)phosphite) as an additive.

[0058] In this embodiment, first, the split vent 35 was closed, and carrier gases such as helium and nitrogen were supplied to the heating furnace 21 from the carrier gas source 27 via the flow rate control device 26 at a flow rate of 2 ml / min, while the heating furnace 21 was heated to 100°C by the heater 22. Next, with the suction pump 5 activated, 0.2 mg of EVA contained in the sample cup 6 was placed into the heating furnace 21 as a sample, and the temperature of the heating furnace 21 was raised from 100°C to 380°C at a rate of 20°C / min and held at 380°C for 1 minute, thereby thermally desorbing the additives and other components contained in the EVA in a free state, and generating a first gas-phase component mixture.

[0059] After the first gas-phase component mixture was generated, the EVA sample was moved to a location unaffected by the heating of the furnace 21, while still contained in the sample cup 6.

[0060] The entire amount of the generated first gas-phase component mixture was introduced into a pre-column 31 at a temperature of 40°C via the GC inlet 23 using a suction pump 5. Then, from the second gas-phase component mixture introduced into the pre-column 31, the components with a boiling point above 40°C were trapped in the pre-column 31 as the first analyte.

[0061] Next, the split vent 35 was opened, the suction pump 5 was stopped, the temperature of the constant temperature bath 3 was maintained at 40°C for 2 minutes, and then the temperature was raised from 40°C to 320°C at a rate of 20°C / min and maintained at 320°C for 14 minutes to heat the pre-column 31 and vaporize the first analyte. Then, the vaporized first analyte was introduced into the main separation column 32 to separate it into individual gas phase components, and the separated individual gas phase components were detected by the detection means 41 to obtain a total ion chromatogram (TIC) of the components contained in the EVA in a free state. The results are shown in the upper part of Figure 2. In addition, the extracted ion chromatogram (EIC) of oxidized irgaphos 168 with m / z 647, which was prepared separately, is shown in the lower part of Figure 2.

[0062] From Figure 2, among the components obtained by thermal desorption of EVA, the peak with a retention time of approximately 24 minutes can be identified as oxidized irgaphos 168.

[0063] Next, with the split vent 35 open, carrier gases such as helium and nitrogen were supplied to the heating furnace 21 from the carrier gas source 27 via the flow rate control device 26 at a flow rate of 200 ml / min, while the heating furnace 21 was heated to a predetermined temperature, for example, 600°C, by the heater 22. Then, with the suction pump 5 activated, the EVA, which had been set aside while contained in the sample cup 6, was introduced into the heating furnace 21 as a sample, and the EVA itself was instantaneously thermally decomposed to generate a second gaseous component mixture.

[0064] Of the generated second gas-phase component mixture, 1 / 100 was introduced into the pre-column 31 at a temperature of 40°C via the GC inlet 23 by the suction pump 5 through the split vent 35, while 99 / 100 was discharged to the outside. Then, of the second gas-phase component mixture introduced into the pre-column 31, the components with a boiling point above 40°C were trapped in the pre-column 31 as the second analyte.

[0065] Next, the suction pump 5 was stopped, the temperature of the constant temperature bath 3 was maintained at 40°C for 2 minutes, and the temperature was raised from 40°C to 320°C at a rate of 20°C / min and maintained at 320°C for 14 minutes to heat the pre-column 31 and vaporize the second analyte. Then, the vaporized second analyte was introduced into the main separation column 32 to separate it into individual gas phase components, and the pyrogram of the components constituting the EVA itself was obtained by detecting the separated individual gas phase components with the detection means 41. The results are shown in Figure 3.

[0066] According to the polymer material analysis method of this embodiment, when analyzing a polymer material using the double-shot method with the gas-phase component analyzer 1 shown in Figure 1, it is clear from Figures 2 and 3 that information on both additives and other components contained in the polymer material in a free state, and the components of the polymer material itself, can be obtained without changing the split ratio of the gas-phase component analyzer 1.

[0067] [Comparative Example 1] In this comparative example, the gas phase component analyzer 1 shown in Figure 1 was used, but it lacked a pre-column 31 and a three-way tube 33. The main separation column 32 was directly connected to the GC inlet 23, and the split ratio of the split vent 35 was set to 1 / 100. In this comparative example, the gas phase component analyzer was the same as in Example 1, and the composition of ethylene vinyl acetate copolymer resin (EVA) as a polymer material was analyzed by the double-shot method.

[0068] Specifically, in this comparative example, the procedure was exactly the same as in Example 1, except that 0.2 mg of EVA contained in the sample cup 6 was first placed in the heating furnace 21 as a sample with the split vent 35 open and without using the suction pump 5. The additives and other components contained in the EVA in a free state were thermally desorbed to produce the first gas phase component mixture.

[0069] Next, 1 / 100 of the generated first gas-phase component mixture was introduced into the main separation column 32 via the split vent 35, while 99 / 100 was discharged to the outside. Subsequently, the first gas-phase component mixture introduced into the main separation column 32 was separated into individual gas-phase components in the main separation column 32 without being trapped in the pre-column 31. The separated individual gas-phase components were detected by the detection means 41 to obtain a total ion chromatogram (TIC) of the components contained in the EVA in a free state and obtained by thermal desorption. The results are shown in the upper part of Figure 4. In addition, the extracted ion chromatogram (EIC) of oxidized irgaphos 168 with m / z 647, which was prepared separately, is shown in the lower part of Figure 4.

[0070] Figure 4 clearly shows that components contained in EVA in a free state and obtained by thermal desorption are undetectable on the TIC.

[0071] Next, without using the suction pump 5, the EVA that had been set aside in the sample cup 6 was placed into the heating furnace 21 as a sample. In this manner, the procedure was exactly the same as in Example 1, and the EVA itself was instantaneously thermally decomposed to produce a second gaseous component mixture.

[0072] The generated second gas-phase component mixture was introduced into the main separation column 32 at a rate of 1 / 100 via the split vent 35, while 99 / 100 was discharged to the outside. Next, the second gas-phase component mixture introduced into the main separation column 32 was separated into individual gas-phase components in the main separation column 32 without being trapped in the pre-column 31. The pyrogram of the components constituting the EVA itself was obtained by detecting the separated individual gas-phase components with the detection means 41. The results are shown in Figure 5.

[0073] According to the analytical method of this comparative example, when analyzing a polymer material using the double-shot method, it is possible to obtain information about the components of the polymer material itself from Figure 5, but it is clear that it is not possible to obtain information about additives and other components contained in the polymer material in a free state from Figure 4. [Explanation of symbols]

[0074] 1... Gas phase component analyzer, 2...Heating means, 3...Thermostatic chamber, 4...Detection means, 5...Suction means 31... The first column, 32...Second column, 33... means of connection, 35...Divided introduction means.

Claims

1. A heating means for heating a sample to generate a gaseous component mixture, A first column into which the gas-phase component mixture generated by the heating means is introduced, An inlet connecting the heating means and the first column, A suction means, A second column, which is a separation column, is connected to the first column and the suction means, respectively, via a three-way tube as a connecting means. A constant temperature bath housing the first column, the second column, and the connecting means, A heater for adjusting the temperature of the constant temperature bath, A detection means for detecting individual gas-phase components separated in the second column, The inlet is provided with a divided introduction means which, when closed, introduces all of the gaseous component mixture generated by the heating means into the first column, and when open, introduces a portion of the gaseous component mixture generated by the heating means into the first column while discharging the remainder to the outside, A control device that controls the operation of the heating means, the heater, the suction means, and the divided introduction means, A gas phase component analyzer equipped with, The first column captures a portion of the gas-phase component mixture, and the second column separates the gas-phase components. Gas phase component analyzer.

2. In the gas phase component analyzer according to claim 1, The control device, A first means for controlling the divided introduction means to a closed state, activating the suction means, and causing the heating means to heat the sample so that components contained in the sample in a free state are thermally desorbed from the sample, thereby generating a first gas-phase component mixture, A second means for stopping the operation of the suction means and heating the first column in the heater to a temperature at which the first analyte captured in the first column, which is contained in the first gas-phase component mixture introduced into the first column through the inlet, can vaporize. A third means controls the divided introduction means to be in an open state, operates the suction means, and causes the heating means to heat the sample so that the sample is thermally decomposed and a second gas phase component mixture is generated. The system includes a fourth means for stopping the operation of the suction means and heating the first column in the heater to a temperature at which the second analyte captured in the first column, which is contained in the second gas-phase component mixture introduced into the first column through the inlet, can vaporize. Polymer material analysis equipment.

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