Nuclear magnetic resonance analysis method for establishing chemical components and condensed state structure of fluorine-containing material and application of nuclear magnetic resonance analysis method

Abstract

The invention provides a nuclear magnetic resonance analysis method for establishing a fluorine-containing material chemical component and a condensed state structure and application thereof.The method comprises the steps that fluorine-containing materials under different working conditions are placed in a unilateral nuclear magnetic resonance spectrometer, in a unilateral non-uniform magnetic field environment, parameters of a spin echo pulse sequence are preset, and the parameters of the spin echo pulse sequence are calculated; exciting a fluorine atomic nucleus and a hydrogen atomic nucleus in the fluorine-containing material by using the spin echo pulse sequence to obtain a coupled nuclear magnetic resonance signal of the fluorine atomic nucleus and the hydrogen atomic nucleus; determining echo peak point data from the coupled nuclear magnetic resonance signals according to preset parameters; performing data processing on the echo peak point data according to the structural characteristics of the fluorine-containing material to obtain relaxation spectrum fingerprint data; performing data transformation on the relaxation spectrum fingerprint data to obtain transverse relaxation time data; and based on the relaxation spectrum fingerprint data and the transverse relaxation time data under different working conditions, establishing a relaxation spectrum fingerprint database and a transverse relaxation time database with fluorine nuclei and hydrogen nuclei coupled in the fluorine-containing material.

Description

Technical Field

[0001] The present disclosure relates to the technical field of rapid detection of fluorine-containing materials, and in particular to a nuclear magnetic resonance analysis method for establishing the chemical composition and condensed structure of fluorine-containing materials and an application thereof, and more specifically to a nuclear magnetic resonance analysis method for establishing the chemical composition and condensed structure of fluorine-containing materials, a nuclear magnetic resonance analysis method for the chemical composition and condensed structure of fluorine-containing materials, and an application of the nuclear magnetic resonance analysis method in the detection of fluorine-containing material performance. Background Art

[0002] With the rapid development of science and technology, fluorine-containing materials have shown broad application prospects in high-end manufacturing fields such as aerospace, electronics and electrical, new energy batteries, biomedicine, weapons manufacturing and packaging due to their unique chemical stability and excellent physical properties.

[0003] However, the rapid development of these fields has put forward more stringent requirements on the quality stability of fluorine-containing materials. At present, the main analytical testing methods used, such as density method, grayscale method and mechanical strength test, can evaluate the macroscopic quality of materials to a certain extent, but the testing process is time-consuming and difficult to meet the needs of rapid testing in large-scale production, which limits production efficiency and market response speed. In addition, existing methods can usually only provide overall, macroscopic quality assessment results, and cannot quickly and effectively analyze the subtle differences that may exist between batches of materials. Therefore, the current analytical testing methods for fluorine-containing materials still need further research to overcome current problems. Summary of the invention

[0004] In view of this, in order to partially solve one of the above-mentioned technical problems, the present disclosure provides a nuclear magnetic resonance analysis method for establishing the chemical composition and condensed structure of fluorine-containing materials and its application.

[0005] According to an embodiment of one aspect of the present disclosure, a nuclear magnetic resonance analysis method for establishing the chemical composition and condensed structure of a fluorine-containing material is provided, comprising:

[0006] The fluorine-containing materials under different working conditions are placed in a unilateral nuclear magnetic resonance apparatus respectively, and the parameters of the spin echo pulse sequence are preset in a unilateral inhomogeneous magnetic field environment, and the fluorine nuclei and hydrogen nuclei in the fluorine-containing materials are excited by the spin echo pulse sequence to obtain coupled nuclear magnetic resonance signals of the fluorine nuclei and hydrogen nuclei;

[0007] According to the parameters of the preset spin echo pulse sequence, the echo peak point data is determined from the coupled nuclear magnetic resonance signal;

[0008] According to the structural characteristics of the fluorine-containing material, the echo peak point data is processed to obtain the relaxation spectrum fingerprint data of the fluorine-containing material;

[0009] Performing data transformation on the relaxation spectrum fingerprint data of the fluorine-containing material to obtain transverse relaxation time data of the fluorine-containing material;

[0010] Based on the relaxation spectrum fingerprint data and transverse relaxation time data under different working conditions, a relaxation spectrum fingerprint database and a transverse relaxation time database of the coupling between fluorine nuclei and hydrogen nuclei in fluorine-containing materials are established;

[0011] Among them, the relaxation spectrum fingerprint data includes the component content and transverse relaxation time of the fluorine-containing material; the transverse relaxation time data includes: the component ratio and dynamic distribution of the fluorine-containing material.

[0012] As another aspect of the present disclosure, a method for nuclear magnetic resonance analysis of chemical composition and condensed structure of fluorine-containing materials is provided, comprising:

[0013] The fluorine-containing material to be tested is placed in a unilateral nuclear magnetic resonance instrument, and in a unilateral inhomogeneous magnetic field environment, the parameters of the spin echo pulse sequence are preset, and the fluorine nuclei and hydrogen nuclei in the fluorine-containing material are excited by the spin echo pulse sequence to obtain coupled nuclear magnetic resonance signals of the fluorine atoms and hydrogen atoms in the fluorine-containing material to be tested;

[0014] According to the parameters of the preset spin echo pulse sequence, the echo peak point data is determined from the coupled nuclear magnetic resonance signal;

[0015] According to the structural characteristics of the fluorine-containing material to be tested, the echo peak point data is processed to obtain the relaxation spectrum fingerprint data of the fluorine-containing material to be tested;

[0016] Performing data transformation on the relaxation spectrum fingerprint data of the fluorine-containing material to be tested, to obtain transverse relaxation time data of the fluorine-containing material to be tested;

[0017] The relaxation spectrum fingerprint data and transverse relaxation time data of the coupling of fluorine nuclei and hydrogen nuclei in the fluorine-containing material to be tested are compared with the relaxation spectrum fingerprint database and transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei in fluorine-containing materials under different working conditions to determine the quality of the fluorine-containing material to be tested or to analyze the chemical composition and condensed structure of the fluorine-containing material to be tested.

[0018] As another aspect of the present disclosure, there is provided an application of the above-mentioned nuclear magnetic resonance analysis method in the performance detection of fluorine-containing materials.

[0019] According to an embodiment of the present disclosure, a nuclear magnetic resonance analysis method for establishing the chemical composition and condensed structure of fluorine-containing materials is provided, which is used to quickly characterize the chemical composition and condensed structure of fluorine-containing materials. By utilizing the magnetic field gradient of unilateral nuclear magnetic resonance, it is possible to simultaneously obtain the coupled nuclear magnetic resonance signals of fluorine nuclei and hydrogen nuclei through a single radio frequency signal, thereby improving the analysis efficiency. At the same time, data processing is performed on the coupled nuclear magnetic resonance signals of fluorine nuclei and hydrogen nuclei, and a relaxation spectrum fingerprint database and a transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei in fluorine-containing materials are established, thereby achieving rapid characterization of the chemical composition and condensed structure of fluorine-containing materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the classification of NMR instruments and the characteristic diagram of unilateral NMR instruments;

[0021] Figure 2 It is a schematic diagram of the structure of the single-sided nuclear magnetic resonance instrument and its signal acquisition principle;

[0022] Figure 3 is a diagram of a process of determining echo peak point data from a coupled nuclear magnetic resonance signal in the present disclosure;

[0023] Figure 4 is a diagram of the thickness direction detection process of the fluorine-containing material disclosed in the present invention;

[0024] Figure 5a 1 is a graph showing echo peak points of different batches of tetrafluoroethylene raw materials in Example 1 of the present disclosure;

[0025] Figure 5b is a fitting curve diagram of batch 39 of tetrafluoroethylene raw material in Example 1 of the present disclosure;

[0026] Figure 5c is a spectrum of the relaxation spectrum fingerprint data of batch 39 tetrafluoroethylene raw materials in Example 1 of the present disclosure after inverse Laplace transformation;

[0027] Figure 6 It is a diagram of the device for online detection of the sample to be tested and a fitting curve diagram in the embodiment 1 of the present disclosure;

[0028] Figure 7 is a spectrum of the relaxation spectrum fingerprint data of the sample to be tested in the embodiment 1 of the present disclosure after inverse Laplace transformation;

[0029] Figure 8 is a graph of echo peak points of three adhesive materials in Embodiment 2 of the present disclosure;

[0030] Fig. 9 It is a one-dimensional contour diagram of the thickness direction of the proton exchange membrane in Example 3 of the present disclosure. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in conjunction with specific embodiments.

[0032] The endpoints and any values ​​of the ranges disclosed in this disclosure are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed in this disclosure.

[0033] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0034] Nuclear Magnetic Resonance (NMR) technology, as the result of the interaction between electromagnetic waves and matter, plays an important role in exploring the microstructure and properties of matter. The basic principle of NMR is that the magnetic moment of an atomic nucleus with a non-zero spin quantum number is oriented along the B0 direction under the action of a static magnetic field B0. The angular frequency ω0 of the precession of the magnetic moment of the atomic nucleus around B0 is the Larmor precession frequency, and its magnitude is related to the detected atomic nucleus, where ω0=γ×B0. During the NMR detection process, when the static magnetic field B1 applied by the radio frequency coil is the same as the Larmor precession frequency of the detected atomic nucleus, resonance will occur, and the applied static magnetic field will generate energy exchange with the atomic nucleus, thereby generating a resonance signal, and realizing an in-depth exploration of the atomic nucleus and its surrounding environment. However, traditional NMR equipment is limited by the uniform magnetic field area generated by the radio frequency coil, resulting in limited test space and only suitable for small volume samples. For example: the diameter of a high-field solid nuclear sample tube is only 3~4 mm, and the diameter of a low-field nuclear magnetic sample is about 10 mm, and the detection area is limited. In addition, in real applications, many samples cannot be brought to the laboratory for analysis, or it is impossible to take samples for analysis.

[0035] Figure 1 It is the classification of nuclear magnetic resonance instruments and the characteristic diagram of single-sided nuclear magnetic resonance instruments. Figure 1As shown, in the process of implementing the present disclosure, it was found that ordinary nuclear magnetic resonance requires the use of a uniform static magnetic field to excite the atomic nuclei in the sample, but is limited by the size of the uniform magnetic field area generated by the radio frequency coil. Low-field nuclear magnetic resonance uses a lower magnetic field intensity, but pays more attention to the macroscopic properties of the sample, such as porosity, moisture content, and molecular dynamics. The unilateral NMR instrument realizes non-destructive online detection of objects of arbitrary volume by placing the magnet and detection coil on one side of the sample, without the need for sample preparation, making on-site detection and analysis of large objects possible. Under non-uniform magnetic field conditions, the spectral width of the spin system of large-volume samples may exceed the effective coverage of the radio frequency field, converting traditional radio frequency pulses into selective pulses, increasing the complexity of the analysis.

[0036] Figure 2 The figure is a schematic diagram of the structure of a single-sided nuclear magnetic resonance instrument and its signal acquisition principle.

[0037] like Figure 2 As shown, the sample is placed in a static magnetic field with a magnetic field gradient, and the hydrogen and fluorine nuclei in the sample will produce Larmor precession along the direction of the static magnetic field. Usually, due to the different gyromagnetic ratios of hydrogen and fluorine, their precession frequencies are also different under the same magnetic field strength, and multiple channels (multiple RF signals) are required to detect different elements. However, due to the existence of the gradient magnetic field of the unilateral nuclear magnetic resonance itself, hydrogen and fluorine atoms at different positions have the same precession frequency. This allows them to be excited simultaneously in the same detection coil and distinguished based on position. By adjusting the RF pulse to match the precession frequency of hydrogen atoms, the frequency of multi-element nuclear magnetic signals can be simultaneously acquired through a single channel (single RF signal), thereby achieving rapid analysis of the chemical and structural characteristics of the sample.

[0038] In this regard, the present disclosure proposes a nuclear magnetic resonance analysis method for establishing the chemical composition and condensed structure of fluorine-containing materials, which is used to quickly characterize the chemical composition and condensed structure of fluorine-containing materials. By using the magnetic field gradient of unilateral nuclear magnetic resonance and excitation by a single radio frequency signal, the fluorine nuclei ( 19 F) and hydrogen nucleus ( 1 H) coupled NMR signals at different positions, significantly improving the analysis efficiency. The coupled NMR signals of fluorine nuclei and hydrogen nuclei are processed, and then the relaxation spectrum fingerprint database and transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei in fluorine-containing materials are constructed, thereby realizing the rapid characterization of the chemical composition and condensed structure of fluorine-containing materials. In addition, this method uses a magnetic field gradient field to characterize the material in situ, without the need for sampling or pretreatment of the sample, realizing non-destructive testing, and has no specific requirements for the volume and quality of the sample, further enhancing its practicality and convenience.

[0039] According to an embodiment of one aspect of the present disclosure, there is provided a nuclear magnetic resonance analysis method for establishing the chemical composition and condensed structure of a fluorine-containing material, comprising:

[0040] The fluorine-containing materials under different working conditions are placed in a unilateral nuclear magnetic resonance apparatus respectively, and the parameters of the spin echo pulse sequence are preset in a unilateral inhomogeneous magnetic field environment, and the fluorine nuclei and hydrogen nuclei in the fluorine-containing materials are excited by the spin echo pulse sequence to obtain coupled nuclear magnetic resonance signals of the fluorine nuclei and hydrogen nuclei;

[0041] According to the parameters of the preset spin echo pulse sequence, the echo peak point data is determined from the coupled nuclear magnetic resonance signal;

[0042] According to the structural characteristics of the fluorine-containing material, the echo peak point data is processed to obtain the relaxation spectrum fingerprint data of the fluorine-containing material;

[0043] Performing data transformation on the relaxation spectrum fingerprint data of the fluorine-containing material to obtain transverse relaxation time data of the fluorine-containing material;

[0044] Based on the relaxation spectrum fingerprint data and transverse relaxation time data under different working conditions, a relaxation spectrum fingerprint database and a transverse relaxation time database of the coupling between fluorine nuclei and hydrogen nuclei in fluorine-containing materials are established;

[0045] Among them, the relaxation spectrum fingerprint data includes the component content and transverse relaxation time of the fluorine-containing material; the transverse relaxation time data includes: the component ratio and dynamic distribution of the fluorine-containing material.

[0046] According to an embodiment of the present disclosure, a nuclear magnetic resonance analysis method for establishing the chemical composition and condensed structure of fluorine-containing materials is provided, which is used to quickly characterize the chemical composition and condensed structure of fluorine-containing materials. By utilizing the inhomogeneous gradient magnetic field of unilateral nuclear magnetic resonance, the fluorine nuclei and hydrogen nuclei in the fluorine-containing material are excited under a single radio frequency signal, so that the coupled nuclear magnetic resonance signals of the fluorine nuclei and the hydrogen nuclei are simultaneously acquired through a single radio frequency signal, thereby improving the efficiency of data acquisition and analysis. Furthermore, the coupled nuclear magnetic resonance signals of the fluorine nuclei and the hydrogen nuclei are processed to construct a relaxation spectrum fingerprint database and a transverse relaxation time database of the coupling of the fluorine nuclei and the hydrogen nuclei in the fluorine-containing material, which are used to characterize the chemical composition and condensed structure of the fluorine-containing material, and at the same time serve as a quick reference for material properties, thereby achieving rapid characterization of the chemical composition and condensed structure of the fluorine-containing material.

[0047] According to the embodiments of the present disclosure, fluorine-containing materials under different working conditions include: fluorine-containing materials from different batches; and / or fluorine-containing materials at different service stages. For example, in the application scenario of engineering fluoroplastics manufacturing, there are polytetrafluoroethylene (PTFE) materials manufactured in different production batches, and different batches of materials may have different properties due to fluctuations in the source of raw materials and mixing and mis-material phenomena during the production process; in the scenario of electronic device manufacturing, there are fluorine-containing rubber seals in different service stages (such as the early, middle and late stages), and their performance may change during use due to factors such as wear, aging or chemical corrosion. By studying fluorine-containing materials under different working conditions, the quality, stability, reliability and other properties of the materials can be analyzed.

[0048] According to the embodiments of the present disclosure, fluorine-containing materials under different working conditions are placed in a unilateral nuclear magnetic resonance apparatus respectively, and in a unilateral inhomogeneous magnetic field environment, the parameters of the spin echo pulse sequence are preset, and the fluorine nuclei and hydrogen nuclei in the fluorine-containing material are excited by the spin echo pulse sequence to obtain coupled nuclear magnetic resonance signals of the fluorine nuclei and hydrogen nuclei. The parameters of the preset spin echo pulse sequence include: radio frequency pulse width, repeated acquisition time, scanning echo time, number of echoes, acquisition time, and number of scans. The spin echo pulse sequence is preferably a CPMG (Carr-Purcell-Meiboom-Gill) pulse sequence. For example, when analyzing polytetrafluoroethylene (PTFE) materials, a CPMG pulse sequence is used, with a RF pulse width of 10 μs, a repeated acquisition time of 350 ms, a scanning echo time of 44 μs, 100 echoes, an acquisition time of 10 μs, and 300 scans; when analyzing fluorinated proton exchange membranes, a CPMG pulse sequence is used, with a RF pulse width of 6 μs, a repeated acquisition time of 200 ms, a scanning echo time of 47 μs, 256 echoes, an acquisition time of 20 μs, 512 scans, and a preset spatial resolution of 50 μm. The coupled nuclear magnetic resonance signal of the fluorine nucleus and the hydrogen nucleus is the coupling of the nuclear magnetic resonance signal of the fluorine nucleus with the nuclear magnetic resonance signal of the hydrogen nucleus; wherein, the coupled nuclear magnetic resonance signal of the fluorine nucleus and the hydrogen nucleus is expressed as: δ=δ H +δ F ; where δ is the chemical shift of the coupling signal, δ H is the chemical shift of hydrogen nuclei in fluorine-containing materials, δ F is the chemical shift of the fluorine nucleus in the fluorine-containing material.

[0049] In the embodiments of the present disclosure, the fluorine-containing material is excited by utilizing the magnetic field gradient effect in the unilateral nuclear magnetic resonance technology, and then under the action of a single radio frequency signal, the coupled nuclear magnetic resonance signals of the fluorine nuclei and the hydrogen nuclei can be simultaneously collected using a single signal, thereby improving the efficiency of the analysis process.

[0050] According to an embodiment of the present disclosure, echo peak point data is determined from the coupled nuclear magnetic resonance signal according to the parameters of the preset spin echo pulse sequence.

[0051] Figure 3 is a diagram of the process of determining echo peak point data from coupled nuclear magnetic resonance signals in the present disclosure. Figure 3 As shown, after applying a 90-degree pulse, a 180-degree pulse is applied to achieve phase recombination of the transverse magnetization flux to obtain the echo signal, and then a 180-degree RF pulse is applied to detect the spin echo signal. According to the preset echo pulse sequence parameters, the echo peak point data is determined and collected.

[0052] According to the embodiments of the present disclosure, different structural features will affect the arrangement and movement of polymer chains in the material, thereby affecting the nuclear magnetic resonance signal of the fluorine-containing material. Therefore, it is necessary to perform data processing on the echo peak point data according to the structural characteristics of the fluorine-containing material to obtain the relaxation spectrum fingerprint data of the fluorine-containing material. Specifically including: according to the structural characteristics of the fluorine-containing material, determine the data processing method for the echo peak point data and perform data processing to obtain the relaxation spectrum fingerprint data of the fluorine-containing material. Wherein, the structural characteristics of the fluorine-containing material are semi-crystalline polymers or cross-linked polymers. The molecular structure and kinetic behavior of semi-crystalline polymers and cross-linked polymers are significantly different. By determining the data processing method according to the structural characteristics of the fluorine-containing material, the relaxation spectrum fingerprint data of the coupling of fluorine nuclei and hydrogen nuclei in the fluorine-containing material can be accurately obtained. The data processing method includes two-component fitting or single-component fitting, and data fitting processing is performed based on different fitting tools, and the fitting tool is preferably a conventional mathematical fitting tool.

[0053] According to the embodiments of the present disclosure, when the structural characteristics of the fluorine-containing material are semi-crystalline polymers, the fluorine-containing material is, for example, polytetrafluoroethylene (PTFE), fluorine-containing resin F2314, fluorine-containing resin F2311, and perfluorosulfonic acid material (PFSA). The semi-crystalline polymer contains two components, a rigid phase (crystalline phase) and a flexible phase (amorphous phase). The echo peak point data is processed by a two-component fitting method, and the contents of the two components and their respective transverse relaxation times can be distinguished and quantified to obtain the relaxation spectrum fingerprint data of the fluorine-containing material, and further characterize the microstructure and phase distribution of the fluorine-containing material. Furthermore, the two components include: a rigid phase component and a flexible phase component, and the relaxation spectrum fingerprint data includes: the component content of the rigid phase of the fluorine-containing material, the component content of the flexible phase, the transverse relaxation time of the rigid phase, and the transverse relaxation time of the flexible phase.

[0054] Specifically, the two-component fitting method is expressed as:

[0055]

[0056] in, is the acquisition time of the coupled NMR signal;

[0057] For fluorine-containing materials, the collection time is The coupled NMR signal intensity at the time;

[0058] For fluorine-containing materials =0 initial coupled NMR signal intensity;

[0059] is the component content of the rigid phase in the fluorine-containing material;

[0060] is the component content of the flexible phase in the fluorine-containing material;

[0061] is the transverse relaxation time of the rigid phase of the fluorine-containing material;

[0062] is the transverse relaxation time of the flexible phase of the fluorine-containing material;

[0063] is the structure factor of the rigid phase of the fluorine-containing material;

[0064] is the structural factor of the flexible phase of the fluorine-containing material.

[0065] Performing data transformation on the relaxation spectrum fingerprint data of the fluorine-containing material to obtain the transverse relaxation time data of the fluorine-containing material includes: performing data transformation on the relaxation spectrum fingerprint data by inverse Laplace transformation to obtain the transverse relaxation time data of the fluorine-containing material.

[0066] When the structural feature of the fluorine-containing material is a semi-crystalline polymer, the relaxation spectrum fingerprint data of the fluorine-containing material is subjected to an inverse Laplace transform to obtain a spectrum with two peaks, and the two peaks in the spectrum are the rigid phase and the flexible phase in the fluorine-containing material.

[0067] At this time, the transverse relaxation time data includes:

[0068] Peak positions of two peaks: Dynamic characteristic relaxation time of rigid phase component and flexible phase component of fluorine-containing material;

[0069] The peak areas of the two peaks; the component ratio of the rigid phase and the component ratio of the flexible phase of the fluorine-containing material;

[0070] The half-width of the two peaks (full-width at half height coverage area): the dynamic distribution of the rigid phase and the dynamic distribution of the flexible phase. The wider the half-width, the wider the distribution of the dynamic characteristics of the phase.

[0071] According to the embodiments of the present disclosure, when the structural feature of the fluorine-containing material is a cross-linked polymer, the fluorine-containing material is such as fluororubber (FKM), fluorosilicone rubber (FVMQ) and fluorinated synthetic rubber (FFKM), etc., and the cross-linked polymer structure can be regarded as an integral flexible phase. The echo peak point data is processed by a single component fitting method to obtain the relaxation spectrum fingerprint data of the fluorine-containing material, thereby characterizing its overall structural characteristics. The single component is a flexible phase component, and the relaxation spectrum fingerprint data includes the component content of the flexible phase of the fluorine-containing material and the transverse relaxation time of the flexible phase.

[0072] The single component fitting method is expressed as:

[0073]

[0074] Performing data transformation on the relaxation spectrum fingerprint data of the fluorine-containing material to obtain the transverse relaxation time data of the fluorine-containing material includes: performing data transformation on the relaxation spectrum fingerprint data by inverse Laplace transformation to obtain the transverse relaxation time data of the fluorine-containing material.

[0075] When the structural feature of the fluorine-containing material is a cross-linked polymer, the relaxation spectrum fingerprint data of the fluorine-containing material is subjected to an inverse Laplace transform to obtain a spectrum with a single peak, and the single peak in the spectrum is the flexible phase in the fluorine-containing material.

[0076] At this time, the transverse relaxation time data includes:

[0077] Peak positions of the two peaks: Dynamic characteristic relaxation time of the flexible phase component of the fluorine-containing material;

[0078] Peak area of ​​a single peak: component of the flexible phase of the fluorine-containing material;

[0079] Half-peak width (half-maximum full-width coverage area) of a single peak: dynamic distribution of the rigid phase of the fluorine-containing material. The dynamic distribution is the distribution range of the time required for the motion state of the component to change.

[0080] According to another aspect of the present disclosure, there is provided a method for nuclear magnetic resonance analysis of chemical composition and condensed structure of fluorine-containing materials, comprising:

[0081] The fluorine-containing material to be tested is placed in a unilateral nuclear magnetic resonance instrument, and in a unilateral inhomogeneous magnetic field environment, the parameters of the spin echo pulse sequence are preset, and the fluorine nuclei and hydrogen nuclei in the fluorine-containing material are excited by the spin echo pulse sequence to obtain coupled nuclear magnetic resonance signals of the fluorine nuclei and hydrogen nuclei in the fluorine-containing material to be tested;

[0082] According to the parameters of the preset spin echo pulse sequence, the echo peak point data is determined from the coupled nuclear magnetic resonance signal;

[0083] According to the structural characteristics of the fluorine-containing material to be tested, the echo peak point data is processed to obtain the relaxation spectrum fingerprint data of the fluorine-containing material to be tested;

[0084] Performing data transformation on the relaxation spectrum fingerprint data of the fluorine-containing material to be tested, to obtain transverse relaxation time data of the fluorine-containing material to be tested;

[0085] The relaxation spectrum fingerprint data and transverse relaxation time data of the coupling of fluorine nuclei and hydrogen nuclei in the fluorine-containing material to be tested are compared with the relaxation spectrum fingerprint database and transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei in fluorine-containing materials under different working conditions to determine the quality of the fluorine-containing material to be tested or to analyze the chemical composition and condensed structure of the fluorine-containing material to be tested.

[0086] According to the embodiments of the present disclosure, by comparing the relaxation spectrum fingerprint data and transverse relaxation time data of the coupling of fluorine nuclei and hydrogen nuclei in the fluorine-containing material to be tested with the established relaxation spectrum fingerprint database and transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei of fluorine-containing materials under different working conditions, the chemical component characteristics of the fluorine-containing material to be tested and the subtle differences in its condensed structure can be efficiently identified. It not only provides a non-destructive non-destructive testing method, but also significantly improves the analysis speed, and can quickly analyze and evaluate the performance of fluorine-containing materials.

[0087] According to an embodiment of the present disclosure, the above-mentioned nuclear magnetic resonance analysis method also includes: performing material characterization tests on fluorine-containing materials under different working conditions to obtain test results, and according to the test results, calibrating the data in the relaxation spectrum fingerprint database and the transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei. Among them, the test method includes: one or more of infrared spectroscopy, scanning electron microscopy, X-ray computed tomography (CT), etc. Material properties include: service stage level, quality level, and failure level of fluorine-containing materials. For example, infrared spectroscopy and scanning electron microscopy are used to test fluorine-containing materials in different service stages (1 to 3 years of service, 3 to 6 years of service, and 6 to 10 years of service). According to the results of infrared spectroscopy and scanning electron microscopy, the relaxation spectrum fingerprint database and transverse relaxation time database data of fluorine-containing materials in different service stages are calibrated as primary (1 to 3 years of service), intermediate (3 to 6 years of service) and final (6 to 10 years of service).

[0088] According to another aspect of the present disclosure, there is provided an application of the above-mentioned nuclear magnetic resonance analysis method in the performance analysis of fluorine-containing materials.

[0089] According to an embodiment of the present disclosure, the performance analysis of the fluorine-containing material includes: determining the quality of the fluorine-containing material to be tested.

[0090] For example: Use material testing methods to classify relaxation spectrum fingerprint databases and / or transverse relaxation time databases of fluorine nuclei and hydrogen nuclei coupled in different batches of fluorine-containing materials, distinguish qualified products from unqualified products, and determine the error range of qualified products. Compare the relaxation spectrum fingerprint data and transverse relaxation time data of fluorine nuclei and hydrogen nuclei coupled in the fluorine-containing material to be tested with the relaxation spectrum fingerprint database and transverse relaxation time database of fluorine nuclei and hydrogen nuclei coupled in different batches of fluorine-containing materials. According to the comparison results, determine whether the fluorine-containing material to be tested is within the error range of qualified products. Samples within the error range are qualified, and samples exceeding the error are unqualified.

[0091] According to an embodiment of the present disclosure, the performance analysis of the fluorine-containing material includes: analyzing the service status of the fluorine-containing material.

[0092] For example: using material testing methods to classify the service status of the relaxation spectrum fingerprint database and / or transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei in fluorine-containing materials at different service stages, comparing the relaxation spectrum fingerprint data and transverse relaxation time data of the coupling of fluorine nuclei and hydrogen nuclei in the fluorine-containing materials to be tested with the relaxation spectrum fingerprint database and transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei in different batches of fluorine-containing materials, and analyzing the service status of the fluorine-containing materials to be tested based on the comparison results.

[0093] According to an embodiment of the present disclosure, the performance analysis of the fluorine-containing material includes: distinguishing the material chemical components of the fluorine-containing material.

[0094] For example: the relaxation spectrum fingerprint data and transverse relaxation time data of the coupling of fluorine nuclei and hydrogen nuclei in the fluorine-containing material to be tested are compared with the relaxation spectrum fingerprint database and transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei in fluorine-containing materials of different chemical compositions, and the chemical compositions of the fluorine-containing materials are distinguished according to the comparison results.

[0095] Furthermore, by using unilateral nuclear magnetic resonance combined with a thickness displacement device, it is also possible to detect the fluorine-containing material in the thickness direction and characterize the thickness change of a certain component of the fluorine-containing material during service.

[0096] Figure 4 It is a diagram of the thickness direction detection process of the fluorine-containing material disclosed in the present invention.

[0097] like Figure 4As shown, the combination of a unilateral nuclear magnetic resonance instrument and a displacement device can detect and analyze fluorine-containing materials in the thickness direction. The sample is placed on a detection platform in a static magnetic field environment with a magnetic field gradient, and the detection probe on the movable displacement device controls the detection position and moves it. By controlling the displacement device, the coupled nuclear magnetic signals of fluorine and hydrogen nuclei can be excited and captured at different thickness positions of the fluorine-containing material. By processing the coupled nuclear magnetic signals, a contour map of the fluorine-containing material in the thickness direction is further constructed, and the fluorine-containing material in the thickness direction is detected and analyzed.

[0098] In order to make the purpose, technical scheme and advantages of the present disclosure more clear, the present disclosure is further described in detail below in conjunction with specific embodiments. Specific techniques or conditions not specified in the embodiments are conventional methods and can be carried out according to the techniques or conditions described in the literature in the art or according to the product instructions.

[0099] Embodiment 1:

[0100] In the aerospace field, the protective layer of cables and optical cables is crucial to ensure the reliability of equipment under extreme conditions. The protective layer material is usually made of fluorine-containing materials such as tetrafluoroethylene (PTFE). Batch-to-batch fluctuations or mixing errors in PTFE raw materials will have a significant impact on the mechanical strength of the cable in high and low temperature environments (-55°C ~180°C). Therefore, this embodiment 1 provides a nuclear magnetic resonance analysis method for the chemical composition and condensed structure of fluorine-containing materials to analyze the quality of PTFE raw materials. Specifically comprising the following steps:

[0101] Step 1: Sample each batch of PTFE raw materials produced, place different batches of PTFE raw materials in a single-sided nuclear magnetic resonance instrument, and preset the parameters of the spin echo pulse sequence in a single-sided inhomogeneous magnetic field environment: use a radio frequency pulse width of 10 μs, a repeated acquisition time of 350 ms, a scanning echo time of 44 μs, 100 echoes, an acquisition time of 10 μs, and a scanning number of 300 times. Use the spin echo pulse sequence to excite the fluorine nuclei and hydrogen nuclei in the fluorine-containing material to obtain the coupled nuclear magnetic resonance signals of the fluorine nuclei and hydrogen nuclei;

[0102] Step 2: According to the parameters of the preset spin echo pulse sequence, the echo peak point data is determined from the coupled nuclear magnetic resonance signal. Figure 5a 1 is a graph showing echo peak points of different batches of tetrafluoroethylene raw materials in Example 1 of the present disclosure;

[0103] Step 3: Use a two-component fitting method to perform a two-component fitting on the echo peak point data. The two-component fitting method is:

[0104]

[0105] in, is the acquisition time of the coupled NMR signal;

[0106] The PTFE raw material is collected at a time of The coupling signal strength at the moment;

[0107] For PTFE raw materials =0 when the initial signal strength;

[0108] is the component content of the rigid phase in the PTFE raw material;

[0109] is the component content of the flexible phase in the PTFE raw material;

[0110] is the transverse relaxation time of the rigid phase of PTFE raw material;

[0111] is the transverse relaxation time of the flexible phase of PTFE raw material;

[0112] is the structure factor of the rigid phase containing PTFE raw material;

[0113] is the structural factor of the flexible phase of PTFE raw material.

[0114] The relaxation spectrum fingerprint data of the PTFE raw material is obtained, wherein the relaxation spectrum fingerprint data includes the component content of the rigid phase of the PTFE raw material, the component content of the flexible phase, the transverse relaxation time of the rigid phase, and the transverse relaxation time of the flexible phase.

[0115] Figure 5b is a fitting curve diagram of batch 39 tetrafluoroethylene raw materials in Example 1 of the present disclosure, such as Figure 5b As shown, taking batch 39 as an example, the PTFE raw material of batch 39 is fitted with two components by the following formula to obtain the corresponding fitting curve and relaxation spectrum fingerprint data of the PTFE raw material: the rigid phase component content is 0.65, the flexible phase component content is 0.35, and the transverse relaxation time of the rigid phase (T 2r ) is 0.077ms, and the transverse relaxation time of the flexible phase (T 2m ) is 0.96ms.

[0116] Step 4: Perform an inverse Laplace transform on the relaxation spectrum fingerprint data of the PTFE raw material to obtain the transverse relaxation time data of the fluorine-containing material;

[0117] Figure 5cis the spectrum of the relaxation spectrum fingerprint data of batch 39 tetrafluoroethylene raw materials in Example 1 of the present disclosure after inverse Laplace transformation, such as Figure 5c As shown, taking batch 39 as an example, by performing inverse Laplace transform on the PTFE raw material of batch 39, the corresponding spectrum and transverse relaxation time data of the PTFE raw material are obtained: the rigid peak area is 0.87, the flexible peak area is 0.20, the rigid peak peak position is 0.31ms, the flexible peak peak position is 1.19ms, the rigid peak half-width is 0.69, and the flexible peak half-width is 0.33.

[0118] Step 5: Based on the relaxation spectrum fingerprint data and transverse relaxation time data of different batches of PTFE raw materials, a relaxation spectrum fingerprint database and a transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei in fluorine-containing materials are established, and the relaxation spectrum fingerprint database data are recorded in Table 1, and the transverse relaxation time database data are recorded in Table 2:

[0119] Table 1

[0120]

[0121] Table 1

[0122]

[0123] Table 2

[0124]

[0125] Table 2

[0126]

[0127] According to the relaxation spectrum fingerprint database in Table 1, the qualified standards of PTFE raw materials are calibrated as follows: the content of rigid phase is 62~67%, the content of flexible phase is 33~38%, the transverse relaxation time of rigid phase is 0.05~0.08 ms, and the transverse relaxation time of flexible phase is 0.89~1.05 ms. According to the transverse relaxation time database in Table 2, the qualified standards of PTFE raw materials are calibrated as follows: rigid peak area is 0.82~0.99, flexible peak area is 0.13~0.25, rigid peak peak position is 0.28ms~0.43ms, flexible peak peak position is 1.18ms~1.20ms, rigid peak half-peak width is 0.53~0.87, and flexible peak half-peak width is 0.22~0.47.

[0128] Step 6: placing the sample to be tested in a unilateral nuclear magnetic resonance instrument, and in a unilateral inhomogeneous magnetic field environment, using the same preset spin echo pulse sequence parameters as in step 1, exciting the fluorine nuclei and hydrogen nuclei in the sample to be tested, and obtaining coupled nuclear magnetic resonance signals of the fluorine nuclei and hydrogen nuclei;

[0129] According to the parameters of the preset spin echo pulse sequence, the echo peak point data is determined from the coupled nuclear magnetic resonance signal;

[0130] The echo peak point data were fitted with a two-component fitting method to obtain the relaxation spectrum fingerprint data of the sample to be tested.

[0131] Figure 6 It is an optical photograph and a fitting curve diagram of the online detection of the sample to be tested in Example 1 of the present disclosure.

[0132] Figure 7 It is the spectrum of the relaxation spectrum fingerprint data of the sample to be tested in Example 1 of the present disclosure after inverse Laplace transformation.

[0133] like Figure 6 , Figure 7 As shown in Table 1 and Table 2, the relaxation spectrum fingerprint data of the sample to be tested is that the content of the rigid phase is 64%, the content of the flexible phase is 36%, the relaxation time of the rigid phase is 0.07 ms, and the relaxation time of the flexible phase is 0.95 ms. The rigid peak area is 0.96, the flexible peak area is 0.22, the rigid peak peak position is 0.33, the flexible peak peak position is 1.19, the rigid peak half-peak width is 0.60, and the flexible peak half-peak width is 0.24. The relaxation spectrum fingerprint data of the sample to be tested is compared with the qualified standards of PTFE raw materials. If it meets the qualified standards, it can be allowed to enter the factory.

[0134] Example 2

[0135] Polymer-Bonded Explosive (PBX) has the characteristics of high energy density, excellent stability and easy processing. PBX explosives are mainly composed of a mixture of polymers, binders and other additives. Among them, the binder usually uses fluorine-containing polymers, such as PTFE binder, fluorine-containing polymer F2311 binder and F2314 binder. The molar ratio of vinylidene fluoride (C2H2F2, VDF) to chlorotrifluoroethylene (C2ClF3, CTFE) in F2311 binder and F2314 binder is 1:1 and 1:4 respectively.

[0136] The molecular structures of fluoropolymer F2311 binder and F2314 binder are:

[0137]

[0138] In order to avoid the occurrence of wrong binder materials and mixed materials during production, this embodiment 2 provides a nuclear magnetic resonance analysis method for the chemical composition and condensed structure of fluorine-containing materials to distinguish the chemical groups of fluorine-containing materials. Specifically, it includes the following steps:

[0139] Step 1: Place three adhesive materials: PTFE adhesive, F2311 adhesive and F2314 adhesive in a unilateral nuclear magnetic resonance instrument. In a unilateral inhomogeneous magnetic field environment, preset the parameters of the spin echo pulse sequence: use a RF pulse width of 6 μs, a repeated acquisition time of 500 ms, a scanning echo time of 30 μs, an echo number of 100, an acquisition time of 1 μs, and a scanning number of 128 times. Use the spin echo pulse sequence to excite the fluorine nuclei and hydrogen nuclei in the three adhesives, respectively, and obtain the corresponding coupled nuclear magnetic resonance signals of the fluorine nuclei and hydrogen nuclei;

[0140] Step 2: According to the parameters of the preset spin echo pulse sequence, the echo peak point data is determined from the coupled nuclear magnetic resonance signal;

[0141] Step 3: Use a two-component fitting method to process the echo peak point data of the three adhesives respectively to obtain the relaxation spectrum fingerprint data of the three adhesives.

[0142] Figure 8 This is a graph of echo peak points of three adhesive materials in Example 2 of the present disclosure.

[0143] like Figure 8 As shown, there are obvious differences in the echo peak point data of the three adhesive materials.

[0144] Step 4: Perform inverse Laplace transform on the relaxation spectrum fingerprint data of the three binders respectively to obtain the transverse relaxation time data of the fluorine-containing material;

[0145] Step 5: Establish a relaxation spectrum fingerprint database and a transverse relaxation time database for the coupling of fluorine nuclei and hydrogen nuclei in the three binder materials. The relaxation spectrum fingerprint data include the component content of the rigid phase, the component content of the flexible phase, the transverse relaxation time of the rigid phase, and the transverse relaxation time of the flexible phase of the PTFE binder, F2311 binder, and F2314 binder, respectively; the transverse relaxation time database includes the component ratio of the rigid phase, the component ratio of the flexible phase, the dynamic distribution of the rigid phase, and the dynamic distribution of the flexible phase of the PTFE binder, F2311 binder, and F2314 binder, respectively.

[0146] Step 6: placing the binder to be tested in a unilateral nuclear magnetic resonance instrument, and in a unilateral inhomogeneous magnetic field environment, using the same preset spin echo pulse sequence parameters as in step 1, exciting the fluorine nuclei and hydrogen nuclei in the binder to be tested, and obtaining coupled nuclear magnetic resonance signals of the fluorine nuclei and the hydrogen nuclei;

[0147] According to the parameters of the preset spin echo pulse sequence, the echo peak point data is determined from the coupled nuclear magnetic resonance signal;

[0148] The echo peak point data is fitted by two-component fitting to obtain the relaxation spectrum fingerprint data of the adhesive to be tested; the relaxation spectrum fingerprint data of the adhesive to be tested is subjected to inverse Laplace transformation to obtain the transverse relaxation time data of the adhesive to be tested. The relaxation spectrum fingerprint data and transverse relaxation time data of the adhesive to be tested are compared with the relaxation spectrum fingerprint database and transverse relaxation time database of the three adhesive materials to quickly distinguish the type of the adhesive to be tested.

[0149] Example 3

[0150] Hydrogen fuel cells use redox reactions to generate electricity efficiently, and have significant advantages such as high efficiency, no pollution, no noise, and zero carbon emissions. The proton exchange membrane in hydrogen fuel cells is mainly made of perfluorosulfonic acid (PFSA) material. At present, porous expanded polytetrafluoroethylene (e-PTFE) porous membrane is used as a reinforcing matrix to be composited with PFSA material to prepare an enhanced composite proton exchange membrane (RCM). By introducing ePTFE materials with stronger mechanical stability in the form of a composite, the total thickness of the membrane can be effectively reduced while ensuring the mechanical strength and dimensional stability of the proton exchange membrane, thereby reducing the use of PFSA ion cross-linked polymers and reducing preparation costs. This Example 3 provides a nuclear magnetic resonance analysis method for the chemical composition and condensed structure of fluorine-containing materials, which is used to detect the thickness direction of e-PTFE and PFSA components in the proton exchange membrane, and includes the following steps:

[0151] Step 1: Place the proton exchange membrane to be tested in a unilateral nuclear magnetic resonance instrument, and preset the parameters of the spin echo pulse sequence in a unilateral inhomogeneous magnetic field environment: use a radio frequency pulse width of 6 μs, a repeated acquisition time of 200 ms, a scanning echo time of 47 μs, an echo number of 256, an acquisition time of 20 μs, a scanning number of 512 times, and a preset spatial resolution of 50 μm. Use the spin echo pulse sequence to respectively excite the fluorine nuclei and hydrogen nuclei in the proton exchange membrane to be tested, and obtain the corresponding coupled nuclear magnetic resonance signals of the fluorine nuclei and hydrogen nuclei;

[0152] Step 2: According to the parameters of the preset spin echo pulse sequence, the echo peak point data is determined from the coupled nuclear magnetic resonance signal;

[0153] Step 3: Use a two-component fitting method to process the echo peak point data of the proton exchange membrane to be tested, and obtain the relaxation spectrum fingerprint data of the proton exchange membrane to be tested.

[0154] Step 4: Perform inverse Laplace transform on the relaxation spectrum fingerprint data of the proton exchange membrane to be tested, and obtain the transverse relaxation time data of the proton exchange membrane to be tested;

[0155] Among them, the relaxation spectrum fingerprint data includes the component content of the rigid phase of the proton exchange membrane to be tested, the component content of the flexible phase, the transverse relaxation time of the rigid phase, and the transverse relaxation time of the flexible phase; the transverse relaxation time data includes the component ratio of the rigid phase of the proton exchange membrane to be tested, the component ratio of the flexible phase, the dynamic distribution of the rigid phase, and the dynamic distribution of the flexible phase.

[0156] Step 5: Generate a one-dimensional contour map in the thickness direction of the proton exchange membrane based on the transverse relaxation time data and the preset spatial resolution, and analyze the thickness direction of the e-PTFE and PFSA components in the proton exchange membrane to be tested.

[0157] Fig. 9 It is a one-dimensional contour diagram of the thickness direction of the proton exchange membrane in Example 3 of the present disclosure.

[0158] like Fig. 9 As shown, the one-dimensional contour diagram can be used to observe the changes in chemical composition along the thickness direction of the membrane and analyze the directional positions of fluorine-containing materials of different chemical components in the proton exchange membrane.

[0159] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present disclosure. It should be understood that the above description is only a specific embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure should be included in the protection scope of the present disclosure.

Claims

1. A nuclear magnetic resonance analysis method for establishing the chemical composition and condensed structure of fluorine-containing materials, comprising: The fluorine-containing materials under different working conditions are placed in a unilateral nuclear magnetic resonance apparatus respectively, and under a unilateral inhomogeneous magnetic field environment, the parameters of the spin echo pulse sequence are preset, and the fluorine nuclei and hydrogen nuclei in the fluorine-containing materials are excited by the spin echo pulse sequence to obtain coupled nuclear magnetic resonance signals of the fluorine nuclei and the hydrogen nuclei; Determining echo peak point data from the coupled nuclear magnetic resonance signal according to preset parameters of the spin echo pulse sequence; According to the structural characteristics of the fluorine-containing material, the echo peak point data is processed to obtain relaxation spectrum fingerprint data of the fluorine-containing material; Performing data transformation on the obtained relaxation spectrum fingerprint data of the fluorine-containing material to obtain transverse relaxation time data of the fluorine-containing material; Based on the relaxation spectrum fingerprint data and transverse relaxation time data under different working conditions, a relaxation spectrum fingerprint database and a transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei in the fluorine-containing material are established; Wherein, the relaxation spectrum fingerprint data includes the component content and transverse relaxation time of the fluorine-containing material; the transverse relaxation time data includes: the component ratio and dynamic distribution of the fluorine-containing material.

2. The method according to claim 1, wherein: The coupled nuclear magnetic resonance signal of the fluorine nucleus and the hydrogen nucleus is the coupling of the nuclear magnetic resonance signal of the fluorine nucleus and the nuclear magnetic resonance signal of the hydrogen nucleus; The coupled nuclear magnetic resonance signal of the fluorine nucleus and the hydrogen nucleus is expressed as: δ = δ H +δ F ; The δ is the chemical shift of the coupling signal, The δ H is the chemical shift of the hydrogen nuclei in the fluorine-containing material, The δ F is the chemical shift of the fluorine nuclei in the fluorine-containing material.

3. The method according to claim 1, wherein: According to the structural characteristics of the fluorine-containing material, the echo peak point data is processed to obtain the relaxation spectrum fingerprint data of the fluorine-containing material, including: According to the structural characteristics of the fluorine-containing material, determining a data processing method for the echo peak point data and performing data processing to obtain relaxation spectrum fingerprint data of the fluorine-containing material, wherein the structural characteristics of the fluorine-containing material are semi-crystalline polymers or cross-linked polymers, and the data processing method includes two-component fitting or single-component fitting; Performing data transformation on the relaxation spectrum fingerprint data of the fluorine-containing material to obtain the transverse relaxation time data of the fluorine-containing material includes: The relaxation spectrum fingerprint data is transformed by inverse Laplace transformation to obtain transverse relaxation time data of the fluorine-containing material.

4. The method according to claim 3, wherein: In the case where the structural feature of the fluorine-containing material is a semi-crystalline polymer, the echo peak point data is processed by a two-component fitting method to obtain relaxation spectrum fingerprint data of the fluorine-containing material, wherein the two components include a rigid phase component and a flexible phase component, and the relaxation spectrum fingerprint data includes the component content of the rigid phase of the fluorine-containing material, the component content of the flexible phase, the transverse relaxation time of the rigid phase, and the transverse relaxation time of the flexible phase; When the structural feature of the fluorine-containing material is a cross-linked polymer, the echo peak point data is processed by a single component fitting method to obtain relaxation spectrum fingerprint data of the fluorine-containing material, wherein the single component is a flexible phase component, and the relaxation spectrum fingerprint data includes the component content of the flexible phase of the fluorine-containing material and the transverse relaxation time of the flexible phase.

5. The method according to claim 4, wherein: The two-component fitting method is expressed as: The single component fitting method is expressed as: is the acquisition time of the coupled nuclear magnetic resonance signal; The fluorine-containing material is collected at a time of The coupled NMR signal intensity at the time; The fluorine-containing material =0 initial coupled NMR signal intensity; is the component content of the rigid phase in the fluorine-containing material; is the component content of the flexible phase in the fluorine-containing material; is the transverse relaxation time of the rigid phase of the fluorine-containing material; is the transverse relaxation time of the flexible phase of the fluorine-containing material; is the structure factor of the rigid phase of the fluorine-containing material; is the structural factor of the flexible phase of the fluorine-containing material.

6. The method according to claim 3, wherein: In the case where the structural feature of the fluorine-containing material is a semi-crystalline polymer, the transverse relaxation time data includes: the component ratio of the rigid phase of the fluorine-containing material, the component ratio of the flexible phase, the dynamic distribution of the rigid phase, the dynamic distribution of the flexible phase, the dynamic characteristic relaxation time of the rigid phase component and the dynamic characteristic relaxation time of the flexible phase component; In the case where the structural feature of the fluorine-containing material is a cross-linked polymer, the transverse relaxation time data includes: the component ratio of the flexible phase of the fluorine-containing material, the dynamic distribution of the flexible phase, and the dynamic characteristic relaxation time of the flexible phase component; The kinetic distribution is the distribution range of the time required for the motion state of the component to change.

7. The nuclear magnetic resonance analysis method according to claim 1, wherein: The fluorine-containing materials under different working conditions include: fluorine-containing materials from different batches; and / or fluorine-containing materials at different service stages.

8. A method for nuclear magnetic resonance analysis of chemical composition and condensed structure of fluorine-containing materials, comprising: Placing the fluorine-containing material to be tested in a unilateral nuclear magnetic resonance instrument, in a unilateral inhomogeneous magnetic field environment, presetting the parameters of a spin echo pulse sequence, and using the spin echo pulse sequence to excite the fluorine nuclei and hydrogen nuclei in the fluorine-containing material to obtain coupled nuclear magnetic resonance signals of the fluorine nuclei and hydrogen nuclei in the fluorine-containing material to be tested; Determining echo peak point data from the coupled nuclear magnetic resonance signal according to preset parameters of the spin echo pulse sequence; According to the structural characteristics of the fluorine-containing material to be tested, the echo peak point data is processed to obtain relaxation spectrum fingerprint data of the fluorine-containing material to be tested; Performing data transformation on the obtained relaxation spectrum fingerprint data of the fluorine-containing material to be tested to obtain transverse relaxation time data of the fluorine-containing material to be tested; The relaxation spectrum fingerprint data and transverse relaxation time data of the coupling of fluorine nuclei and hydrogen nuclei in the fluorine-containing material to be tested are compared with the relaxation spectrum fingerprint database and transverse relaxation time database of the coupling of fluorine nuclei and hydrogen nuclei in fluorine-containing materials under different working conditions to determine the quality of the fluorine-containing material to be tested or to analyze the chemical composition and condensed structure of the fluorine-containing material to be tested.

9. The nuclear magnetic resonance analysis method according to claim 8, further comprising: Performing material characterization tests on the fluorine-containing materials under the different working conditions to obtain test results; According to the test results, the data in the relaxation spectrum fingerprint database and the transverse relaxation time database of the coupling of the fluorine nuclei and the hydrogen nuclei are graded. The material properties include: the service stage grade, quality grade, and failure grade of the fluorine-containing material.

10. Use of the nuclear magnetic resonance analysis method according to any one of claims 8 to 9 in the detection of properties of fluorine-containing materials.

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