JPH03171544A - High polymer molecular composition analyzing device - Google Patents

Abstract

PURPOSE:To make a preprocessing to a sample unnecessary and to analyze the molecular composition of every sort of high polymer compound rapidly by providing an ultraviolet-ray radiating device and an electron beam radiating device in an ionization chamber. CONSTITUTION:While ultraviolet rays are radiated first from an ultraviolet-ray radiating device 4 on a solid high polymer sample 6 laid in an ionization chamber 1, electron beams are radiated from an electron beam radiating device 5, and at the same time, Ar neutral atoms are radiated from an FAB gun 3. By the radiation of the ultraviolet rays and the electron beams, the combinations between atoms of the high polymer of the sample 6 are cut off in numerous positions in the high molecles, the high molecles are spattered by the Ar atoms radiated from the FAB gun 3, and they are ionized partially and enter to a mass analysis chamber 2. Since the ions produced in such a way are characteristic to the high molecules of the sample 6, and not dissolved minutely, it is very effective to clear the structure unit of the high molecles, and moreover, the electron beams not only cut off the combinations between atoms in the sample 6, but also eliminates the charge of the sample 6 in the spattering of the sample fragments.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a polymer molecular structure analyzer for analyzing the molecular structure of a polymer compound.

[Prior art] Data for analyzing the molecular structure of polymer compounds has been obtained by infrared absorption spectroscopy, Raman spectroscopy, nuclear magnetic resonance spectroscopy, pyrolysis gas chromatography/mass spectrometry, etc. . Each of these has the following characteristics.

Infrared absorption spectroscopy is active in vibrational modes in which the dipole moment of a molecule changes in various vibrations between atoms within a molecule, and each absorption peak on the obtained infrared absorption spectrum is a vibration mode between atoms within a molecule. It is characteristic of bonding. Therefore, it is possible to know what kind of interatomic bonds are present in the molecule, and the molecular structure of the sample polymer compound can be analyzed from information about many such interatomic bonds. In addition, in this method, spectra of many substances are collected and compiled into a database, so
It is also possible to quickly identify substances through computer searches. Raman spectroscopy is active in vibrational modes that change the polarizability of the molecule in various vibrations between atoms within the molecule, and each peak on the obtained Raman scattering spectrum corresponds to each bond between atoms within the molecule. It is characteristic.

Therefore, complementary to infrared absorption spectroscopy, it is possible to determine what kind of interatomic bonds exist within a molecule.
From a large amount of information on such interatomic bonds, it is possible to analyze what kind of interatomic bonds exist in a sample polymer compound and what kind of molecular structure the polymer has. Nuclear magnetic resonance spectroscopy can obtain information about the spins of atomic nuclei in molecules where each spin quantum number is non-zero.

This information includes data on the electron density around the nucleus and the type and number of bonding partners, making it possible to clearly analyze the molecular structure of the sample polymer compound. The pyrolysis gas chromatography/mass spectrometry method involves pyrolyzing fine pieces or trace powders of a sample polymer at high temperatures in an inert gas, separating the resulting pyrolysis gas into portions using a gas chromatograph, and then This is a method of obtaining mass spectra of each component using mass spectrometry. Mass spectra are characteristic of each substance, and therefore each part of the pyrolysis gas can be identified, and the composition of this pyrolysis gas clearly reflects the molecular structure of the sampled polymer compound. Because of this, it is possible to analyze the molecular structure of the polymer. In addition, F
AB (Fast atom bombardment)
One known mass spectrometry method is the method used to analyze substances that are unstable to heat, such as substances in living organisms, and highly polar substances that cannot be easily ionized and subjected to mass analysis using other methods. It enables ionization and mass spectrometry of substances, and is an effective method for analyzing substances in living organisms such as vitamins and enzymes.

[Problem to be solved by the invention]

By the way, the above-mentioned infrared absorption spectroscopy, Raman spectroscopy, nuclear magnetic resonance spectroscopy, pyrolysis gas chromatography/mass spectrometry, and FAB mass spectrometry are methods for analyzing the molecular structure of polymer compounds, especially solid polymer compounds. , there are various problems as follows. That is, in infrared absorption spectroscopy, one should make the solid polymer into a thin film that does not cause interference fringes and measure it by transmission, make a mirror surface and measure it by ATR method, or make it into a powder and measure it by transmission as a KBr tablet. Alternatively, there are methods such as making it into a powder and measuring it using the diffuse reflection method, but both require some kind of pretreatment as mentioned above before measurement using an infrared absorption method, which poses problems in terms of workability. . With Raman spectroscopy, it is possible to analyze solid polymers as they are, but unless the irradiation position and irradiation angle of the excitation light on the sample are adjusted appropriately, a high-intensity spectrum that is effective for analysis cannot be obtained. In addition, when increasing the output of laser light (excitation light) to obtain a high-intensity spectrum, or focusing the light using a lens system, the sample often denatures due to heat, and in that case, the original information about the sample will no longer be available. In nuclear magnetic resonance spectroscopy, C
Although it has become possible to measure solid samples with the development of the P/MAS (cross-volatization/magic angle binning) method, it is not possible to obtain spectra with the high resolution of liquid samples, and it is still difficult to obtain spectra with complex structures for polymers. It is necessary to dissolve it in some kind of solvent and measure it as a solution sample. In that case, polymers with high molecular weights are difficult to dissolve, especially substances with crosslinked structures such as epoxy resins and vulcanized rubber, and even if they can be made into a solution, the higher the molecular weight, the more difficult it is to dissolve the substances in the solution sample. It may be difficult to obtain a spectrum effective for analysis because the molecular weight per unit volume is small. In pyrolysis gas chromatography/mass spectrometry, the sample is thermally decomposed at high temperatures in an inert gas, so the polymer is decomposed into very small molecules due to radical reactions.
Only the partial structure of each small part of the original polymer can be obtained as information. Furthermore, in most cases, this method does not have selectivity in cutting with respect to the strength or weakness of bonds between atoms in the molecule, so it is often difficult to analyze the molecular structure of the original polymer. As mentioned above, various analytical methods capable of analyzing the molecular structure of polymeric compounds have many problems. In addition, FAB mass spectrometry is an optimal method for analyzing substances with relatively low molecular weights of up to about 3000, especially biological molecules such as vitamins and enzymes, but it is also suitable for analyzing solid polymers as they are. That is difficult.

The purpose of the present invention is to solve the above-mentioned conventional problems, to be able to analyze a polymer compound without any pretreatment, and to obtain effective information regarding its molecular structure. The object of the present invention is to provide a new polymer molecular structure analysis device.

[Means to solve the problem]

In order to achieve the above object, the polymer molecular structure analyzer according to the present invention uses FAB (Fast atom b
A polymer molecular structure analyzer comprising an ionization chamber and a mass spectrometry chamber equipped with a gun (embardment),
The ionization chamber is equipped with an ultraviolet irradiation device that irradiates the sample with ultraviolet rays and an electron beam irradiation device that irradiates the sample with an electron beam.

[Effect]

When a polymer is irradiated with ultraviolet rays and an electron beam in an ionization chamber, interatomic bonds within the polymer are broken according to their bond dissociation energy and dissociation activation energy. Therefore, many characteristic cleavages occur in the sample solid polymer, and the resulting large fragments are
It is sputtered by neutral atoms such as Ar that are simultaneously irradiated from the AB gun, and a portion of it is ionized. The ions generated in this way are characteristic of the sampled polymer and are not decomposed as finely as in the thermal decomposition method, so they are effective in clarifying the structural units of the sampled polymer. be. Furthermore, here, the electron beam not only breaks the interatomic bonds within the sample, but also has the role of erasing the charge on the sample during sputtering of sample fragments.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic diagram of a polymer molecular structure analysis apparatus showing an embodiment of the present invention.

In the figure, this device includes an ionization chamber 1 and a mass spectrometry chamber 2.
In this ionization chamber 1, an FAB gun 3, an ultraviolet irradiation device 4, and an electron beam irradiation device 5 are arranged. To analyze the molecular structure of a polymer using this device, first, a solid polymer sample 6 placed in an ionization chamber 1 is irradiated with ultraviolet light from an ultraviolet irradiation device 4, and an electron beam is emitted from an electron beam irradiation device 5. , and at the same time Ar neutral atoms are irradiated from the FAB gun 3. By this irradiation with ultraviolet rays and electron beams, bonds between atoms in the polymer of the sample are broken at many positions within the molecule, which is sputtered by Ar neutral atoms irradiated by the FAB gun 3, and some of them are ionized and mass Enter analysis room 2. As described above, it is possible to perform mass spectrometry on the structural units of the solid polymer compound used as a sample, and to clarify the molecular structure of the sample. Further, here, the electron beam not only breaks the interatomic bonds within the sample, but also plays the role of erasing the charge on the sample during sputtering of sample fragments. In the above method, by controlling the wavelength and amount of ultraviolet light and the power of the electron beam, it is possible to selectively cleave different types of interatomic bonds in a molecule and control the amount of cleavage. This provides important information for molecular structure analysis.

[Effects of the Invention] As explained above, by using the polymer molecular structure analyzer of the present invention, the molecular structure of all kinds of polymer compounds can be quickly analyzed without any pretreatment of the sample. Can be done.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the present invention. 1...Ionization chamber 3...FAB gun 5...Electron beam irradiation device 2...Mass spectrometry room 4...Ultraviolet irradiation device 6...Polymer sample

Claims (1)

[Claims] (1) FAB (Fastatom bombardmen)
t) A polymer molecular structure analyzer comprising an ionization chamber and a mass spectrometry chamber equipped with a gun, wherein the ionization chamber includes an ultraviolet irradiation device that irradiates the sample with ultraviolet rays, and an electron beam irradiation device that irradiates the sample with an electron beam. A polymer molecular structure analysis device characterized by being equipped with a device.