Polymer material analyzing device and polymer material analyzing method

Abstract

To provide an analysis method of a high polymer material, the method enabling information on a component contained in a high polymer material to be surely acquired by a double shot method.SOLUTION: An analysis method of a high polymer material is performed in the below-mentioned steps comprising: a selection step in which on the basis of a result of a generated gas analysis method of a sample, a temperature region where a first analysis target component is generated, is selected; a first capturing step in which selective introduction means and suction means 5 are activated, the sample is heated and the included component is thermally desorbed, a first gas phase component mixture generated in the temperature region where the first analysis target component is generated, is introduced into a first column 31 and the first analysis target component is captured to the first column 31; a gasification step in which the suction means 5 is stopped and the first analysis target component is gasified, then the first analysis target component is introduced into a second column 32 and is separated, and is detected by detection means 41; a second capturing step in which division introduction means 35 is opened, the selective introduction means is stopped, the suction means 5 is actuated, the sample is thermally decomposed, the second analysis target component is captured to the first column 31, the suction means 5 is stopped for gasifying the second analysis target component and the gasified second analysis target component is introduced into the second column 32 and is separated; and a detection step in which the second analysis target component is detected by the detection means 41.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for analyzing polymeric materials. [Background technology]

[0002] Gas chromatography has been known as a method for analyzing gas phase components. A known gas phase component analyzer (gas chromatograph) for use in gas chromatography includes, for example, a heating means for heating a sample to generate a gas phase component mixture, a separation column connected to the heating means for separating the gas phase component mixture generated by the heating means into individual components, a thermostatic chamber (oven) for accommodating the separation column, and a detector connected to the separation column for detecting the individual components separated by the separation column.

[0003] The heating means generates the gaseous component mixture by thermally decomposing or volatilizing the sample, or by heating the sample to thermally desorb the components contained in the sample. The detector used may be a mass spectrometer (MS) or the like.

[0004] When the composition of a polymeric material is analyzed using the gas phase component analyzer, for example, the polymeric material is first heated to a temperature of about 300°C to thermally desorb the components contained in the polymeric material in a free state to generate a first gas phase component mixture, the first gas phase component mixture is introduced into the separation column to separate it into individual gas phase components, and the separated individual gas phase components are detected with a detector such as the mass spectrometer (MS), etc. Next, after the components contained in the free state have been thermally desorbed, the polymeric material is instantaneously pyrolyzed at a temperature of about 600°C to generate a second gas phase component mixture, the second gas phase component mixture is introduced into the separation column to separate it into individual gas phase components, and the separated individual gas phase components are detected with a detector such as the mass spectrometer (MS).

[0005] The method is sometimes called the double-shot method because the thermal desorption is followed by the pyrolysis.

[0006] Generally, polymeric materials contain additives such as antioxidants and ultraviolet absorbers in amounts of 0.1% by mass or less to improve their performance. For example, ethylene-vinyl acetate copolymer resins contain a phosphorus-based processing stabilizer called Irgafos 168 (tris(2,4-di-tert-butylphenyl)phosphite) as one of the additives.

[0007] For quality control of polymeric materials containing the additives, it is necessary to analyze the composition of the polymeric material. When the composition of the polymeric material is analyzed by the double-shot method, it is thought that information on the components contained in a free state, such as the additives, can be obtained by analyzing the first gaseous mixture of components produced by thermal desorption of the polymeric material, and information on the polymeric material itself can be obtained by analyzing the second gaseous mixture of components produced by thermal decomposition of the polymeric material.

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

[0009] [Patent Document 1] Japanese Patent Application Publication No. 2018-66618 Summary of the Invention [Problem to be solved by the invention]

[0010] When analyzing the composition of the polymeric material by the double-shot method, a small split ratio is preferred for analyzing the second gaseous mixture produced by thermal desorption of the polymeric material itself. However, a small split ratio results in a small amount of the gaseous mixture introduced into the separation column. Therefore, when the first gaseous mixture produced by thermal desorption of the polymeric material is derived from components contained in the polymeric material in a free state and the content of the free components relative to the total polymeric material is as low as 0.1% by mass or less, sufficient detection intensity cannot be obtained, making it impossible to analyze the first gaseous mixture produced by thermal desorption of the polymeric material.

[0011] Therefore, when the first gaseous mixture produced by thermal desorption of the polymeric material is derived from components contained in the polymeric material in a free state and the content of the free components relative to the total polymeric material is as low as 0.1 mass% or less, a large split ratio is preferred for analyzing the first gaseous mixture produced by thermal desorption. However, if the second gaseous mixture produced by thermal desorption of the polymeric material contains large amounts of non-analyte components such as solvent, unreacted methylating agent, or silylating agent, a large split ratio can cause deterioration of the separation column or malfunction of the detector, making it impossible to analyze the second gaseous mixture produced by thermal desorption of the polymeric material.

[0012] To solve the above 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, in the gas phase component analyzer, the split ratio is usually set to a predetermined fixed value, which is inconvenient in that it is difficult to change.

[0014] An object of the present invention is to provide a method for analyzing a polymeric material that overcomes these disadvantages and that can reliably obtain information on both components, such as additives contained in a free state in the polymeric material, and the components of the polymeric material itself, when analyzing the composition of the polymeric material by the double-shot method using the gas phase component analyzer, without changing the split ratio of the gas phase component analyzer. [Means for solving the problem]

[0015] The applicant has already filed a patent application for a gas-phase component analyzer that can prevent deterioration of a separation column or detector due to non-analyte components and achieve excellent detection sensitivity (see Japanese Patent Application No. 2020-215423). The gas-phase component analyzer described in the patent application includes 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 to the first column, a second column (a separation column) connected to the first column via a connecting means, a thermostatic chamber housing the first column, the second column, and the connecting means, and a detecting means for detecting the individual gas-phase components separated by the second column. The gas-phase component analyzer also includes a suction means connected to the connecting means, and a split vent provided at the inlet as a dividing introduction means for introducing a portion of the gas-phase component mixture generated by the heating means into the first separation column and discharging the remainder to the outside.

[0016] According to the gas phase component analyzer described in the patent application, the suction means is first operated, 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 further operated for a predetermined time from the time the sample is introduced or injected. By operating the suction means, the split vent is substantially not operated, and 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 a high-boiling, low-volatile target component to be analyzed and a low-boiling, highly volatile non-target component such as a solvent. Since the first column is set at a temperature higher than the boiling point of the non-target component and lower than the boiling point of the target component, the non-target component is not captured by the first column and is further sucked in the direction of the suction means, while the target component 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 instead sucked into the suction means and released to the outside via the suction means.

[0019] Once the non-analyte components have been released to the outside, the suction means is stopped after the predetermined time has elapsed, and the temperature of the thermostatic chamber is raised to a temperature at which the target components can be vaporized. In this way, the target components captured in the first column are vaporized. Furthermore, when the suction means is stopped, the target components are moved toward the connecting means by the carrier gas, the flow rate of which is controlled by the dividing introduction means.

[0020] At this time, the suction means is stopped and the connection direction of the connection means to the suction means is closed, so the vaporized analyte components are introduced into the second column by the carrier gas. Since the second column is a separation column, the analyte components introduced into the second column are 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] The present inventors have arrived at the present invention by conceiving that when analyzing a polymeric material as a sample by the double-shot method, by improving the gas phase component analysis apparatus described in the aforementioned patent application and further combining the gas phase component analysis method described in the aforementioned patent application with an evolved gas analysis method, it is possible to reliably obtain information on both the components of the polymeric material itself and components contained in the polymeric material in a free state, such as additives, without changing the split ratio of the gas phase component analysis apparatus.

[0022] Therefore, in order to achieve the above object, the method for analyzing a polymeric material of the present invention comprises: a heating means for heating the sample to produce a gas phase component mixture; The aforementioned Generated by heating means The aforementioned a first column into which the gas phase component mixture is introduced; The aforementioned an inlet connecting the heating means and the first column; Through connection means The aforementioned a second column which is a separation column connected to the first column; The aforementioned The first column and The aforementioned The second column and The aforementioned a thermostatic chamber containing the connecting means; The aforementioned detection means for detecting the individual gas phase components separated in the second column; The aforementioned suction means connected to the connection means; The aforementioned Provided at the inlet, A split vent that can be freely opened and closed by a first opening and closing valve and, a purge gas conduit that can be opened and closed by a second on-off valve, and that supplies purge gas to the injection port when in an open state and stops the supply of purge gas to the injection port when in a closed state; A method for analyzing a polymer material using a gas phase component analyzer comprising: The aforementioned selecting a temperature range in which a first analyte component is generated based on the results of evolved gas analysis of the sample; The aforementioned With the suction means activated, The aforementioned In the heating means The aforementioned The sample is heated, The aforementioned The components contained in the sample in a free state The aforementioned thermally desorbing from the sample to form a first gas phase mixture of components; By opening the split vent and the purge gas conduit, the first gaseous mixture of components generated outside the temperature range in which the first target component is generated is led out of the injection port through the split vent. , The split vent is closed and the purge gas conduit is closed, Generated in the temperature range where the first analyte is generated The aforementioned The first gas phase component mixture The aforementioned Through the inlet The aforementioned Introduced into the first column, The aforementioned A first analyte component contained in a first gas phase component mixture is The aforementioned capturing on a first column; The aforementioned The first analyte The aforementioned After capturing in the first column, The aforementioned Stopping the suction means, The aforementioned The first column The aforementioned The first analyte is heated to a temperature at which it can be vaporized. The aforementioned vaporizing the first analyte; Vaporized The aforementioned The first analyte The aforementioned The gas is introduced into a second column to separate the individual gas phase components, and the separated individual gas phase components are The aforementioned detecting with a detection means; With the split vent open, , the purge gas conduit is closed; and , The aforementioned With the suction means activated, The aforementioned After the components contained in a free state are thermally desorbed in the heating means, The aforementioned Heat the sample The aforementioned pyrolyzing the sample to produce a second gas phase mixture of components; The aforementioned A portion of the second gas phase component mixture The aforementioned While being introduced into the first column, The aforementioned the remainder of the second gas phase component mixture , the inlet through the split vent in an open state Externally Derivation death, The aforementioned Introduced in the first column The aforementioned A second analyte component contained in the second gas phase component mixture is The aforementioned capturing on a first column; The aforementioned The second analyte The aforementioned After capturing in the first column, The aforementioned Stopping the suction means, The aforementioned The first column The aforementioned The second analyte is heated to a temperature at which it can be vaporized. The aforementioned vaporizing the second analyte; Vaporized The aforementioned The second analyte The aforementioned The gas is introduced into a second column to separate the individual gas phase components, and the separated individual gas phase components are The aforementioned and detecting the same with a detection means.

[0023] In the method for analyzing a polymeric material of the present invention, first, the polymeric material as the sample is analyzed by evolved gas analysis, and a temperature range in which the first component to be analyzed is generated is selected from the results.

[0024] In the method for analyzing a polymeric material of the present invention, the gas phase component analyzer is then used to first heat the sample to thermally desorb the components contained in the sample in a free state to generate a first gas phase component mixture, which is then introduced into the separation column to separate it into individual gas phase components, and the separated individual gas phase components are detected with a detector.The gas phase component analyzer is then used to instantaneously pyrolyze the sample after the components contained in the free state have been thermally desorbed to generate a second gas phase component mixture, which is then introduced into the separation column to separate it into individual gas phase components, and the separated individual gas phase components are detected with a detector.

[0025] Here, the gas phase component analyzer used in the polymer material analysis method of the present invention is configured to include a gas phase component analyzer equipped with a split vent as a split introduction means described in Patent Application No. 2020-215423, and further equipped with a selective introduction means that selectively 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.

[0026] Therefore, in the method for analyzing a polymeric material of the present invention, the gas phase component analyzer first heats the sample in the heating means while the selective introducing means and the suction means are in operation, thereby thermally desorbing the components contained in the sample in a free state from the sample, thereby generating the first gas phase component mixture consisting of the components contained in the sample in a free state.

[0027] In this case, in the polymeric material analysis method of the present invention, the selective introduction means selectively introduces the first gaseous mixture produced in a temperature range where a first target component is generated into the first column through the inlet, while discharging the first gaseous mixture produced outside that temperature range to the outside, so that the first target component contained in the first gaseous mixture produced in that temperature range is captured in the first column.

[0028] Next, once the first analyte component has been captured in the first column, the selective introducing means and the suction means are stopped, and the first column is heated to a temperature at which the first analyte component can be vaporized to vaporize the first analyte component, and the vaporized first analyte component is introduced into the second column. Since the second column is a separation column, the first analyte component introduced into the second column is separated into individual gas phase components in the second column, and the separated individual gas phase components are detected by the detection means.

[0029] The individual gaseous components constituting the first analyte are, for example, components derived from additives contained in the polymeric material in an amount of 0.1 mass% or less of the total, and are therefore very dilute. However, according to the polymeric material analysis method of the present invention, as described above, of the first gaseous component mixture produced by thermal desorption, only the first gaseous component mixture produced in a temperature range selected for the generation of the first analyte is selectively introduced into the first column and trapped. As a result, the concentration of the first analyte in the first gaseous component mixture trapped in the first column is increased, and sufficient detection intensity can be obtained when detected by the detection means, thereby enabling reliable acquisition of information on the first analyte.

[0030] In the polymeric material analysis method of the present invention, the split introduction means is then opened, the selective introduction means is stopped, and the suction means is operated, and the sample after the components contained in a free state have been thermally desorbed is heated in the heating means to pyrolyze the sample. In this way, the second gaseous component mixture is produced by the pyrolysis of the polymeric material itself that constitutes the sample.

[0031] In this case, in the polymeric material analysis method of the present invention, the split introduction means is open, so that a part of the generated second gaseous mixture is introduced into the first column by the split introduction means, while the remainder is discharged to the outside. Then, from the second gaseous mixture introduced into the first column, the second target component contained in the second gaseous mixture is captured by the first column, while non-target components are aspirated by the suction means and discharged to the outside.

[0032] Next, once the second analyte component 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 component can be vaporized to vaporize the second analyte component, and the vaporized second analyte component is introduced into the second column. Since the second column is a separation column, the second analyte component introduced into the second column is separated into individual gas phase components in the second column, and the separated individual gas phase components are detected by the detection means.

[0033] The second gaseous mixture produced by the thermal decomposition of the polymeric material itself may contain a large amount of non-analyte components, such as solvents. However, according to the polymeric material analysis method of the present invention, as described above, only a portion of the second gaseous mixture produced by the thermal decomposition of the polymeric material itself is introduced into the first column by the split introduction means. Furthermore, from the second gaseous mixture introduced into the first column, only the second analyte component contained therein is captured in 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 gaseous components, which can be reliably detected by the detection means, thereby obtaining information on the second analyte component.

[0034] Therefore, according to the method for analyzing polymeric materials of the present invention, when analyzing polymeric materials by the double-shot method using a gas phase component analyzer in which the selective introduction means has been added to the gas phase component analyzer described in Patent Application No. 2020-215423, by combining it with an evolved gas analysis method, it is possible to reliably obtain information on both components such as additives contained in the polymeric material in a free state and the components of the polymeric material itself, without changing the split ratio of the gas phase component analyzer.

[0035] In the method for analyzing polymeric materials of the present invention, the evolved gas analysis method can be performed using a known device. For example, in a gas phase component analysis device in which the selective introduction means is added to the gas phase component analysis device described in Patent Application No. 2020-215423, the evolved gas analysis method can be performed using a metal tube with an inert inner surface instead of the first column and the second column. [Brief explanation of the drawings]

[0036] [Figure 1] 1 is an explanatory cross-sectional view showing one example of the configuration of a gas phase component analysis device used in the polymer material analysis method of the present invention. [Figure 2] 1 is an explanatory cross-sectional view showing one example of the configuration of a gas phase component analyzer used in evolved gas analysis in the polymer material analysis method of the present invention. FIG. [Figure 3] FIG. 1 shows an example of an analysis of a polymer material by evolved gas analysis using the polymer material analysis method of the present invention. The lower part shows a thermogram obtained by evolved gas analysis, and the upper part shows a mass spectrum of the components contained in Zone A of the thermogram. [Figure 4] FIG. 1 shows an example of an analysis of a polymer material using the polymer material analysis method of the present invention. The upper part is a total ion chromatogram of the component contained in zone A of FIG. 3 among the gas phase component mixture generated by thermal desorption, and the lower part is an extracted ion chromatogram of the component with m / z 647 among the components contained in zone A of FIG. 3. [Figure 5] 5 is a diagram showing an example of analysis of a polymer material by the polymer material analysis method of the present invention, and is a pyrogram of a gas phase component mixture produced by thermal desorption after thermal desorption in FIG. 4. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0037] Next, embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

[0038] The method for analyzing a polymer material according to this embodiment can be carried out using a gas phase component analyzer 1 shown in FIG. 1 and a gas phase component analyzer 11 shown in FIG.

[0039] The gas phase component analyzer 1 shown in Figure 1 is a gas chromatograph used for gas chromatography mass spectrometry (GC / MS), and is equipped with a heating device 2, a thermostatic chamber 3 connected to the heating device 2, and a detection device 4 connected to the thermostatic chamber 3.

[0040] The heating device 2 includes 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 injection port 23 into which the tip of the heating furnace 21 is inserted. The heater 22 heats the heating furnace 21 under predetermined conditions controlled by a temperature control device (not shown). The heating furnace 21 is connected to the top of the GC injection port 23 by a heated pipe or the like, or is detachably attached to the top of the GC injection port 23 without using a pipe or the like. Furthermore, instead of the quartz tube, the heating furnace 21 may be made of a stainless steel tube made inert by forming a thin quartz film on the inner surface.

[0041] The GC injection port 23 is also provided with a heater (not shown), which heats the GC injection port 23 under predetermined conditions using a temperature control device (not shown), similar to the heater 22. If the heating furnace 21 is not connected or attached to the top of the GC injection port 23, a septum (not shown) is attached to the upper end.

[0042] The heating device 2 includes a sample introduction section 24 connected above the heating furnace 21, and a carrier gas conduit 25 is connected to the sample introduction section 24 as a carrier gas introduction means for introducing a carrier gas into the heating furnace 21. The other end of the carrier gas conduit 25 is connected to a carrier gas source 27 via a carrier gas flow rate controller 26. Furthermore, the carrier gas conduit 25 is connected to the GC injection port 23 when the heating furnace 21 is not connected or attached above the GC injection port 23.

[0043] As a result, the carrier gas supplied from the carrier gas source 27 is adjusted to a predetermined flow rate by the carrier gas flow rate controller 26 and introduced into the heating furnace 21 or the GC injection port 23 .

[0044] The thermostatic bath 3 accommodates a pre-column 31 as a first column, a main separation column 32 as a second column that is a separation column, and a three-way pipe (T-shaped pipe) 33 as a connecting means that connects the pre-column 31 and the main separation column 32. One end of the pre-column 31 is inserted into the GC injection port 23 and faces the tip of the heating furnace 21, while the other end is connected to the main separation column 32 via the three-way pipe 33. One end of the main separation column 32 is connected to the pre-column 31 via the three-way pipe 33, while the other end is connected to detection means 41, such as a quadrupole mass spectrometry detector, accommodated in the detection device 4.

[0045] The three-way pipe 33 linearly connects the pre-column 31 and the main separation column 32, and is connected to an exhaust conduit 34 in a direction perpendicular to the direction in which the pre-column 31 and the main separation column 32 are connected. The exhaust conduit 34 is connected to a suction pump 5 such as a vacuum pump provided outside the thermostatic bath 3.

[0046] The pre-column 31 may be, 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 made of a copolymer of diphenylpolysiloxane and dimethylpolysiloxane in a molar ratio of 5:95 on its inner surface; a capillary column with an inner diameter of approximately 0.1 to 0.5 mm and a length of 0.5 to 19 m, the inner surface of which is coated with various polymers; or a capillary tube with a chemically inactivated inner surface without a polymer coating. The main separation column 32 may be, 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 made of a copolymer of diphenylpolysiloxane and dimethylpolysiloxane in a molar ratio of 5:95 on its inner surface.

[0047] The pre-column 31 is detachable from the GC injection port 23 and the three-way tube 33, and the pre-column 31 can be selected depending on the subject of analysis.

[0048] As the detection means 41, in addition to a mass spectrometer (MS) such as the quadrupole mass spectrometer detector, a flame ionization detector (FID), an electron capture detector (ECD), or the like can be used.

[0049] The gas phase component analyzer 1 is also equipped with a split vent 35 at the GC injection port 23 as a split introduction means for introducing a portion of the gas phase component mixture into the pre-column 31 while discharging the remainder to the outside. The split vent 35 can be freely opened and closed by an on-off valve (not shown), and when open, introduces a portion of the gas phase component mixture introduced from the pyrolysis furnace 21 or generated at the GC injection port 23 into the pre-column 31 while discharging the remainder to the outside. The split vent 35 has a 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, set to a predetermined value, for example, 1 / 100.

[0050] The gas phase component analyzer 1 also includes a purge gas conduit 36 ​​as a selective introduction means for selectively introducing a portion of the gas phase component mixture into the precolumn 31 through the GC injection port 23 while discharging the remainder to the outside. The purge gas conduit 36 ​​is connected to a purge gas flow rate controller 38 via an on-off valve 37, and the purge gas flow rate controller 38 is connected to a purge gas source 39.

[0051] When the selective introduction means discharges the gaseous component mixture produced by the heating means 21 to the outside, it opens an on-off valve 37, adjusts the flow rate of purge gas supplied from a purge gas source 39 to a predetermined value using a purge gas flow rate controller 38, and supplies the purge gas from a purge gas conduit 36 ​​to the GC injection port 23. The purge gas supplied to the GC injection port 23 then discharges the gaseous component mixture to the outside via a split vent 35. On the other hand, when the selective introduction means introduces the gaseous component mixture produced by the heating means 21 into the pre-column 31, it closes the on-off valve 37 and stops the supply of the purge gas to the GC injection port 23. As a result, the selective introduction means can selectively introduce a portion of the gaseous component mixture into the pre-column 31, while discharging the remainder to the outside.

[0052] In this embodiment, the selective introduction means is configured so that the purge gas supplied to the GC injection port 23 discharges the gas phase component mixture to the outside via the split vent 35, but the selective introduction means may also be provided with a separate discharge conduit for discharging the purge gas and the gas phase component mixture to the outside.

[0053] The gas phase component analyzer 11 shown in FIG. 2 is a gas phase component analyzer used for evolved gas analysis-mass spectrometry (EGR / MS). 1 The gas phase component analyzer 1 shown in Fig. 1 has the same configuration as the gas phase component analyzer 1, except that an EGA column 40 is provided instead of the pre-column 31 and main separation column 32 of the gas phase component analyzer 1 shown in Fig. 1. The EGA column 40 may be, for example, an inactivated metal capillary tube with an inner diameter of 0.15 mm and a length of 2.5 m, the inner surface of which has been chemically inactivated.

[0054] Next, a method for analyzing a polymer material according to this embodiment using the gas phase component analyzer 1 shown in FIG. 1 and the gas phase component analyzer 11 shown in FIG. 2 will be described.

[0055] The method for analyzing a polymeric material according to the present embodiment is used, for example, when analyzing the composition of a polymeric material containing additives such as antioxidants and ultraviolet absorbers in an amount of 0.1 mass % or less of the total amount by a combination of evolved gas analysis and the double-shot method.

[0056] The polymeric material analysis method of this embodiment will be described below using an example of analyzing the composition of an ethylene vinyl acetate copolymer (EVA) polymeric material, which contains a phosphorus-based processing stabilizer called Irgafos 168 (tris(2,4-di-tert-butylphenyl)phosphite) as an additive.

[0057] In the polymer material analysis method of this embodiment, first, in the gas phase component analyzer 11 shown in FIG. 2, split vent 35 is opened to set the split ratio to 1 / 50, and with the selective introduction means stopped, a carrier gas such as helium or nitrogen is supplied from carrier gas source 27 to heating furnace 21 via flow control device 26 at a flow rate of, for example, 1 ml / min, while heating furnace 21 to a predetermined temperature, for example, 100°C, using heater 22. Next, 0.1 to 0.2 mg of EVA contained in sample cup 6 is placed into heating furnace 21 as a sample. Then, for example, the temperature of heating furnace 21 is increased from 100°C to 700°C at a rate of 20°C / min, and the change in the amount of gas generated from the polymer material is observed, thereby obtaining a thermogram, for example, as shown in the lower part of FIG. 3.

[0058] In the method for analyzing a polymeric material according to this embodiment, the temperature range in which the first component to be analyzed occurs is determined by comparing the mass spectrum of the thermogram profile shown in the lower part of Fig. 3 with libraries such as various databases. For example, the mass spectrum of Zone A in the thermogram profile shown in the lower part of Fig. 3 is shown in the upper part of Fig. 3.

[0059] From the mass spectrum in the upper part of Figure 3, it can be determined that the first target additive, oxidized Irgafos-168, with m / z 647, is contained in Zone A. Therefore, the temperature range of 300 to 360°C corresponding to Zone A is selected as the temperature range in which the first target component is generated.

[0060] In the method for analyzing a polymeric material according to this embodiment, split vent 35 is closed in gas phase component analyzer 1 shown in Fig. 1, and a carrier gas such as helium or nitrogen is supplied to heating furnace 21 from carrier gas source 27 via flow rate controller 26 at a flow rate of, for example, 2 ml / min while heating furnace 21 to a predetermined temperature, for example, 100°C, using heater 22. Next, split vent 35 is opened, and with the selective introduction means and suction pump 5 operating, a sample of, for example, 0.2 mg of EVA contained in sample cup 6 is introduced into heating furnace 21. When the selective introduction means is operating, on-off valve 37 can be freely opened and closed as needed.

[0061] Then, for example, by raising the temperature of the heating furnace 21 from 100°C to 380°C at a rate of 20°C / min and holding it at 380°C for 1 minute, components including the additive Irgafos 168 and the like contained in the polymer material EVA in a free state are thermally desorbed from the polymer material, thereby generating a first gas phase component mixture.

[0062] At this time, in this embodiment, outside the temperature region of 300 to 360°C corresponding to Zone A in the thermogram in the lower part of Fig. 3, on-off valve 37 is opened, and purge gas supplied from purge gas source 39 is adjusted to a predetermined flow rate by purge gas flow rate control device 38 and supplied from purge gas conduit 36 ​​to GC inlet 23. Then, the purge gas supplied to GC inlet 23 discharges the first gas phase component mixture produced outside the temperature region of 300 to 360°C corresponding to Zone A to the outside via split vent 35.

[0063] On the other hand, in the temperature range of 300 to 360°C corresponding to zone A, on-off valve 37 is closed, the supply of the purge gas to GC injection port 23 is stopped, and split vent 35 is closed. As a result, the first gas phase component mixture produced in the temperature range of 300 to 360°C corresponding to zone A is sucked into suction pump 5 and selectively introduced into precolumn 31.

[0064] After the first gas phase component mixture is produced, the polymer material is kept in the sample cup 6 and is moved to a region that is not affected by the heating of the heating furnace 21 .

[0065] At this time, the pre-column 31 is set to a temperature of, for example, 40°C, and of the components contained in the first gaseous component mixture, those having a boiling point above 40°C are regarded as first components to be analyzed and are trapped (captured) in the pre-column 31. On the other hand, of the components contained in the first gaseous component mixture, those having a boiling point of 40°C or less are regarded as non-analyte components and are sucked in by the suction pump 5 and discharged to the outside.

[0066] Next, once the first analyte component produced in the temperature range of 300 to 360°C corresponding to Zone A has been trapped in the pre-column 31, the suction pump 5 is stopped, 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 component can be vaporized, thereby vaporizing the first analyte component. Specifically, the operation of heating the pre-column 31 to a temperature at which the first analyte component can be vaporized is performed by increasing the temperature of the thermostatic bath 3. For example, the temperature of the thermostatic bath 3 is maintained at 40°C for 2 minutes, then increased from 40°C to 320°C at a rate of 20°C / min, and maintained at 320°C for 14 minutes, thereby vaporizing the first analyte component. The vaporized first analyte component is then introduced into the main separation column 32 via the three-way pipe 33. Since the main separation column 32 is a separation column, the first analyte component 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 the total ion chromatogram (TIC) shown in the upper part of Figure 4.

[0067] The total ion chromatogram (TIC) shown in the upper part of Figure 4 is a total ion chromatogram (TIC) of components including the additive Irgafos 168 contained in a free state in EVA as the polymer material. The extracted ion chromatogram (EIC) of oxidized Irgafos 168 at m / z 647 based on libraries of various databases is shown in the lower part of Figure 4.

[0068] From Figure 4, among the components obtained by thermal desorption of EVA, the peak with a retention time of approximately 24 minutes can be identified as oxidized Irgafos-168.

[0069] In the method for analyzing a polymeric material according to this embodiment, once the analysis of the first component to be analyzed is completed, the split vent 35 is opened, and a carrier gas such as helium or nitrogen is supplied to the heating furnace 21 from the carrier gas source 27 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 operating, the polymeric material that has been evacuated while still contained in the sample cup 6 is introduced as a sample into the heating furnace 21, and the polymeric material itself is instantaneously thermally decomposed to produce a second gaseous component mixture.

[0070] At this time, in the method for analyzing polymeric materials of this embodiment, the split vent 35 is opened, so that a portion of the second gas phase component mixture produced is introduced into the pre-column 31 through the split vent 35 in accordance with a predetermined split ratio, while the remainder is discharged to the outside.

[0071] At this time, the pre-column 31 is set to a temperature of, for example, 40°C, and components contained in the second gaseous component mixture having a boiling point above 40°C are trapped in the pre-column 31 as second components to be analyzed. On the other hand, components contained in the second gaseous component mixture having a boiling point of 40°C or lower are sucked in by the suction pump 5 and discharged to the outside as components not to be analyzed. When the second gaseous component mixture contains a large amount of a solvent or the like, many of the solvents have a boiling point of 40°C or lower, and most of these solvents are discharged to the outside as the components not to be analyzed.

[0072] Next, once the second analyte component has been 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 component can be vaporized, thereby vaporizing the second analyte component. Specifically, the operation of heating the pre-column 31 to a temperature at which the second analyte component can be vaporized is performed by increasing the temperature of the thermostatic bath 3. For example, the temperature of the thermostatic bath 3 is maintained at 40°C for 2 minutes, then increased from 40°C to 320°C at a rate of 20°C / min, and maintained at 320°C for 14 minutes, thereby vaporizing the second analyte component, and the vaporized second analyte component is introduced into the main separation column 32 via the three-way pipe 33. Since the main separation column 32 is a separation column, the second component to be analyzed 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 that make up the polymer material itself, as shown in Figure 5.

[0073] As a result, according to the method for analyzing a polymeric material of this embodiment, when a polymeric material is analyzed by the double-shot method using the gas phase component analyzer 1 shown in FIG. 1 , by combining the evolved gas analysis method, it is possible to reliably obtain information on both components such as additives contained in the polymeric material in a free state and the components of the polymeric material itself, without changing the split ratio of the gas phase component analyzer 1. [Explanation of symbols]

[0074] 1, 11...gas phase component analyzer, 2...heating means, 3...constant temperature bath, 4...detection means, 5...suction means, 31...first column, 32...second column, 33...connection means, 35...divided introduction means, 36...selective introduction means, 40...metal tube with inert inner surface.

Claims

1. a heating means for heating the sample to produce a gas phase component mixture; a first column into which the gaseous component mixture produced by the heating means is introduced; an inlet connecting the heating means and a first column; a second column which is a separation column connected to the first column via a connecting means; a thermostatic bath that accommodates the first column, the second column, and the connecting means; detection means for detecting individual gas phase components separated in the second column; suction means connected to the connection means; a split vent provided at the injection port and configured to be freely opened and closed by a first on-off valve; a purge gas conduit that can be opened and closed by a second on-off valve, and that supplies a purge gas to the injection port in an open state and stops the supply of the purge gas to the injection port in a closed state, selecting a temperature range in which a first analyte component is generated based on the results of evolved gas analysis of the sample; heating the sample in the heating means while operating the suction means to thermally desorb components contained in the sample in a free state from the sample to generate a first gaseous mixture; opening the split vent and the purge gas conduit to introduce the first gaseous mixture generated outside the temperature range in which the first target component is generated to the outside of the injection port through the split vent; closing the split vent and the purge gas conduit to introduce the first gaseous mixture generated within the temperature range in which the first target component is generated into the first column through the injection port, thereby capturing the first target component contained in the first gaseous mixture in the first column; After capturing the first analyte component in the first column, stopping the suction means and heating the first column to a temperature at which the first analyte component can be vaporized to vaporize the first analyte component; introducing the vaporized first analyte component into the second column to separate it into individual gas phase components, and detecting the separated individual gas phase components with the detection means; a step of heating the sample from which the components contained in a free state have been thermally desorbed in the heating means while the split vent is open, the purge gas conduit is closed, and the suction means is activated, thereby pyrolyzing the sample and generating a second gas phase component mixture; introducing a portion of the second gaseous mixture into the first column, while discharging the remainder of the second gaseous mixture to the outside of the injection port through the split vent in an open state, and capturing a second analyte component contained in the second gaseous mixture introduced into the first column in the first column; after capturing the second analyte component in the first column, stopping the suction means and heating the first column to a temperature at which the second analyte component can be vaporized, thereby vaporizing the second analyte component; introducing the vaporized second analyte component into the second column to separate it into individual gas phase components, and detecting the separated individual gas phase components with the detection means.

2. 2. The method for analyzing a polymeric material according to claim 1, The evolved gas analysis method includes: The gas phase component analysis is performed using a gas phase component analysis device separate from the gas phase component analysis device, The separate gas phase component analyzer, a heating means for heating the sample to produce a gas phase component mixture; a metal tube having an inert inner surface into which the gaseous component mixture generated by the heating means is introduced; an injection port connecting the heating means and the metal tube; a thermostatic chamber that accommodates the metal tube; a detection means for detecting individual gas phase components separated by the metal tube; a split vent provided at the injection port and configured to be freely opened and closed by a first on-off valve; a purge gas conduit that can be opened and closed by a second on-off valve, and that supplies a purge gas to the injection port when the conduit is open and stops the supply of the purge gas to the injection port when the conduit is closed; A method for analyzing a polymer material, comprising:

3. A heating means for heating the sample to generate a gas phase component mixture; a first column into which the gaseous component mixture produced by the heating means is introduced; an inlet connecting the heating means and a first column; a second column which is a separation column connected to the first column via a connecting means; a thermostatic bath that accommodates the first column, the second column, and the connecting means; detection means for detecting individual gas phase components separated in the second column; suction means connected to the connection means; a split vent provided at the injection port and configured to be freely opened and closed by a first on-off valve; a purge gas conduit that can be opened and closed by a second on-off valve, and that supplies purge gas to the injection port when in the open state and stops the supply of purge gas to the injection port when in the closed state.

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