Analytical method for redox-generated radical mechanism and its initiation of polymerization

Abstract

The application provides a method for analyzing a redox-generated free radical mechanism and initiation polymerization, which is suitable for tracking dynamic changes of molecular vibration characteristic peaks of reactants, intermediates and products in a reaction process by using an in-situ attenuated total reflection infrared spectrum device, and optimizing an in-situ electron paramagnetic resonance spectrum monitoring system for identifying types of free radicals generated in the reaction process and variation rules of intensities of the free radicals with time in real time, and analyzing a redox reaction path based on infrared spectrum data and free radical data, and is especially suitable for dynamically monitoring and analyzing the redox-generated free radicals to analyze the redox-generated free radical mechanism.

Description

Technical Field

[0001] This invention relates to the field of free radical-initiated polymerization, and in particular to an analytical method applicable to the mechanism of free radical generation by redox reactions and its initiation of polymerization. Background Technology

[0002] Currently, water-soluble polymers on the market are mainly synthetic polymers, with applications covering five key areas: water purification, daily chemical products, oil and gas extraction, food engineering, and papermaking and biopharmaceuticals. Aqueous solution free radical polymerization is the core technology for achieving efficient synthesis of water-soluble polymers. Redox initiation systems, due to their advantages such as efficient free radical generation at room temperature, have become an indispensable initiation route for aqueous solution and emulsion free radical polymerization, and are widely used in industry. Compared with thermal initiators that require external heat energy, redox initiation systems exhibit significant advantages such as fast reaction rates and short induction periods due to their low activation energy. This not only facilitates the synthesis of ultra-high molecular weight polymers at low temperatures but also effectively reduces the emission of volatile organic compounds (VOCs).

[0003] However, the fundamental challenge of redox-initiated systems lies in their extremely complex reaction mechanisms. This process involves rapid electron transfer between oxidants and reductants, accompanied by the generation of various short-lived free radicals and transient intermediates. Due to the extremely short lifespan and low concentration of these reactive species, the specific reaction pathways and the evolution of key intermediates have not yet been clearly revealed. This fundamentally hinders the customized production of specific polymer structures (such as ultra-high molecular weight polymers and specific sequence distributions), limiting further improvements in material properties and the full exploitation of their application potential.

[0004] Existing analytical methods cannot solve the above-mentioned problems. Traditional offline detection methods or ordinary in-situ testing methods are difficult to capture in real time and in situ the rapid and complex redox reactions that generate free radicals and the polymerization process they initiate. Although EPR can identify the types of free radicals, traditional methods cannot reflect their dynamic generation and decay kinetics. Although IR can track changes in molecular structure, it cannot obtain key information on free radicals and reaction intermediates and complexes. This kind of research, which relies heavily on endpoint detection or indirect inference, is like "blind men touching an elephant." It causes a mismatch between the reaction monitoring analytes and their time dimension, resulting in inaccurate and incomplete reaction mechanisms and regulatory laws, and even serious biases in conclusions. The lack of understanding of the identification of key intermediates and the dynamic evolution of free radicals has become a major bottleneck restricting the rational design of initiation systems and the precise control of polymerization processes, ultimately affecting the molecular weight distribution, compositional uniformity, and final performance of polymer products.

[0005] Therefore, developing a high-time-resolution analytical method capable of real-time monitoring of changes in molecular structure and exploring the mechanism of free radical generation by redox reactions has become a key problem that urgently needs to be solved in this field. Summary of the Invention

[0006] The purpose of this invention is to provide an analytical method applicable to the mechanism of free radical generation by redox reactions and its initiation of polymerization, particularly suitable for dynamic monitoring and analysis of free radicals generated by redox reactions to elucidate the mechanism of free radical generation by redox reactions.

[0007] To achieve the above objectives, this scheme integrates in-situ attenuated total reflectance infrared spectroscopy with time-resolved online in-situ electron paramagnetic resonance spectroscopy as its core, combined with time-series methods, and uses gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS), and nuclear magnetic resonance (NMR) as auxiliary verification tools. This provides a particularly suitable analytical device and method for investigating the mechanism of redox free radical generation. The analytical device and method provided in this scheme can achieve real-time, online, and dynamic monitoring and correlation analysis of the entire process in the redox initiation system, from reactants and intermediates to free radicals and final products, realizing comprehensive mechanistic analysis from the molecular level to the free radical level.

[0008] This scheme provides an analytical method applicable to the mechanism of free radical generation from redox reactions and its initiation of polymerization, including:

[0009] Oxidizing agent solution and reducing agent solution are injected into an in-situ attenuated total reflectance infrared spectroscopy device to carry out the reaction and obtain infrared spectral data of the reaction products. The infrared spectral data of the reaction products include the molecular vibrational characteristic peaks of reactants, intermediates and products and their dynamic changes. The redox mechanism of functional groups is obtained based on the infrared spectral data.

[0010] Oxidant and reducing agent solutions were injected into a conventional in-situ electron paramagnetic resonance spectroscopy monitoring system to obtain raw free radical data. Based on the raw free radical data, the functional group redox mechanism was optimized to obtain the free radical redox mechanism.

[0011] Oxidant solution, reducing agent solution and free radical scavenger are injected into an optimized in-situ electron paramagnetic resonance spectroscopy monitoring system to obtain intermediate free radical data. Based on the intermediate free radical data, the free radical redox mechanism is optimized to obtain the redox reaction pathway.

[0012] In some embodiments, the in-situ attenuated total reflectance infrared spectroscopy device is used to track the dynamic changes of molecular vibrational characteristic peaks of reactants, intermediates, and products in a reaction process. The in-situ attenuated total reflectance infrared spectroscopy device includes an infrared spectrometer 204, a KBr spectrometer 205, and a spectral analysis device 206 connected in sequence. A liquid-phase ATR reaction cell 202 is disposed on the KBr spectrometer 205 within a water bath jacket 201. ZnSe crystals 203 are placed at the bottom of the liquid-phase ATR reaction cell 202, and the liquid-phase ATR reaction cell 202 is equipped with a stirrer 211 and a temperature controller. The system includes a controller 209, a pressure sensor 214, and an airflow controller 208. An optimized in-situ electron paramagnetic resonance (EPR) spectroscopy monitoring system is used to identify the types of free radicals generated during the reaction process and their intensity changes over time. This system includes an EPR main unit, which is equipped with an oxidant injection path 101, a reducing agent injection path 102, and a free radical scavenger injection path 103 connected via a three-way connector 104. A standard in-situ EPR spectroscopy monitoring system is a standard EPR, and therefore will not be described in detail here.

[0013] This scheme utilizes the aforementioned in-situ attenuated total reflectance infrared spectroscopy equipment to monitor changes in the molecular vibrational characteristic peaks of reactants, intermediates, and products. This allows for the tracking of the dynamic processes of substance consumption and generation. Furthermore, by observing the real-time changes in functional groups, it infers how the process from reactants to products occurs and preliminarily obtains the redox mechanism of functional groups.

[0014] Ordinary in-situ electron paramagnetic resonance spectroscopy monitoring system is used to test oxidants, reducing agents and redox mixtures to obtain raw free radical data. The raw free radical data records the changes in the types and intensities of free radicals over time. Based on the raw free radical data, the functional group redox mechanism is optimized to obtain the free radical redox mechanism. At this point, the functional group redox mechanism can be refined from the free radical level, that is, the changes in functional groups are subdivided into changes in free radicals to obtain the free radical redox mechanism.

[0015] It should be noted that if the original free radical data shows that the free radicals have been present for a long time, it means that there are intermediates. Therefore, this scheme further utilizes an optimized in-situ electron paramagnetic resonance spectroscopy monitoring system to study the oxidant solution, reducing agent solution and free radical scavenger to obtain intermediate free radical data. Based on the optimized free radical data, the mechanism of free radical acquisition around the intermediate is supplemented, and then the redox mechanism of free radicals is optimized based on the intermediate free radical data to obtain the redox reaction pathway.

[0016] like Picture 12As shown, the optimized in-situ electron paramagnetic resonance spectroscopy monitoring system of this scheme optimizes the reaction flow path on the EPR main device, which consists of an oxidant injection flow path 101, a reductant injection flow path 102, and a free radical scavenger injection flow path 103. The input ends of the oxidant injection flow path 101 and the reductant injection flow path 102 are connected to the micro-injection pump 1, and the output ends of the oxidant injection flow path 101 and the reductant injection flow path 102 are connected to the redox agent mixing flow path 105 through a three-way connector 104. The input end of the free radical scavenger injection flow path 103 is connected to the micro-injection pump 1, and the output end of the free radical scavenger injection flow path 103 and the output end of the redox agent mixing flow path 105 are connected to the free radical scavenger mixing flow path 106 through a three-way connector 104. The free radical scavenger mixing flow path 106 is connected to the U-shaped capillary reactor 107 of the EPR main device.

[0017] Regarding the EPR main unit, the EPR main unit includes an EPR liquid nitrogen finger dewar 112 and a U-shaped capillary reactor 107 placed inside the EPR liquid nitrogen finger dewar 112. The input end of the U-shaped capillary reactor 107 is connected to the free radical scavenger mixing flow path 106, and the output end of the U-shaped capillary reactor 107 is connected to the waste liquid flow path 108 and the waste liquid tank 109. The EPR liquid nitrogen finger dewar 112 is placed inside the resonant cavity 111 formed by two electromagnets and the microwave bridge 110 and overlaps with the resonant cavity 111.

[0018] In some embodiments, the main reaction portion of the U-shaped capillary reactor 107 is directly opposite the detection area of ​​the resonant cavity 111.

[0019] In some embodiments, the U-shaped capillary reactor 107 is made of quartz.

[0020] In some embodiments, the EPR liquid nitrogen finger dewar 112 is connected to the liquid nitrogen bottle 113, and the temperature is adjusted to 77~600K by the liquid nitrogen in the liquid nitrogen bottle 113.

[0021] Furthermore, the EPR liquid nitrogen finger dewar 112 is coaxially arranged and partially nested with the resonant cavity 111, so the liquid nitrogen in the liquid nitrogen bottle 113 is used to adjust the temperature of the resonant cavity 111 region.

[0022] The two electromagnets of the EPR main device provide a magnetic field B0 to the resonant cavity 111, while the microwave bridge provides a microwave v perpendicular to the magnetic field. Therefore, the sample free radicals in the resonant cavity 111 absorb energy and transition from a low energy level to a high energy level, thereby obtaining the corresponding spectrum.

[0023] like Picture 13As shown, the in-situ attenuated total reflectance infrared spectroscopy device provided in this scheme uses a KBr spectrometer 205 and a ZnSe crystal 203 at the bottom of the liquid phase ATR reaction cell 202. The infrared light passes through the KBr spectrometer 205 and undergoes multiple total reflections inside the ZnSe crystal 203. Part of the light is absorbed by the sample, and the remaining light enters the spectral analysis device 206. The spectral analysis device 206 analyzes the infrared light online and outputs the infrared spectrum and various data on the display.

[0024] In some embodiments, the detection wavenumber range of the in-situ attenuated total reflectance infrared spectrometer is 650–2000 cm⁻¹. -1 .

[0025] In some embodiments, the infrared spectrometer 204 serves as a signal emission source, transmitting broad-spectrum infrared light directionally to the KBr spectrometer 205. The KBr spectrometer 205 filters infrared beams within a specific range and applies them to the sample in the liquid-phase ATR reaction cell 202. The reflected light carrying molecular vibration information is collected and transmitted to the spectral analysis device 206 to be converted into interpretable infrared spectral data.

[0026] In some embodiments, the liquid phase ATR reactor 202 is a reactor capable of withstanding high temperature, high pressure and sealing requirements.

[0027] In some embodiments, the liquid-phase ATR reaction tank 202 is placed in a water bath jacket 201 to precisely control and stabilize the reaction temperature of the liquid-phase ATR reaction tank 202. Furthermore, the water bath jacket 201 is controlled by a low-temperature constant-temperature water bath control device 207.

[0028] In some embodiments, the liquid phase ATR reaction tank 202 is connected to a thermocouple 210 and a temperature controller 209 to control and accurately measure the real-time temperature of the reaction liquid in the liquid phase ATR reaction tank 202 in real time, with a measurement accuracy of ± 0.1 °C. Combined with the water bath jacket 201, the temperature range in the liquid phase ATR reaction tank 202 can reach 15 °C to 100 °C.

[0029] In some embodiments, a stirrer 211 is provided in the liquid phase ATR reaction tank 202 for stirring the reactants, and the stirring speed is generally set to 200 rpm / min.

[0030] In some embodiments, the micro-injection pump 1, the airflow controller 208, and the ventilation duct 212 are all individually connected to the liquid-phase ATR reaction cell 202 via valve 213. The airflow controller 208 introduces 100% inert gas into the liquid-phase ATR reaction cell 202 to purge it, so that the liquid-phase ATR reaction cell 202 maintains an inert gas environment. The micro-injection pump 1 can hold multiple syringes and is connected to the injection needle valve of the liquid-phase ATR reaction cell 202 via a duct, which can precisely control the injection rate and volume.

[0031] In some embodiments, pressure sensor 214 is also connected to the liquid phase ATR reactor. The connected pressure sensor 214 is used to measure the pressure inside the liquid phase ATR reaction tank 202, and the pressure measurement accuracy is ±0.1 MPa.

[0032] Specifically, oxidant and reducing agent solutions with a predetermined molar ratio for studying the mechanism of free radical generation by redox are injected into an in-situ attenuated total reflectance infrared spectroscopy device, a primary in-situ electron paramagnetic resonance (EPR) spectroscopy monitoring system, and an optimized in-situ EPR spectroscopy monitoring system. The optimized in-situ EPR spectroscopy monitoring system also requires the additional injection of a free radical scavenger.

[0033] As previously described, the oxidant solution and the reducing agent solution are precisely injected into the in-situ attenuated total reflectance infrared spectroscopy device via micro-injection pump 1. The oxidant solution is injected into the oxidant injection flow path 101 of the optimized in-situ electron paramagnetic resonance spectroscopy monitoring system via micro-injection pump 1, the reducing agent solution is injected into the reducing agent injection flow path 102 of the optimized in-situ electron paramagnetic resonance spectroscopy monitoring system via micro-injection pump 1, and the free radical scavenger is injected into the free radical scavenger injection flow path 103 of the optimized in-situ electron paramagnetic resonance spectroscopy monitoring system via micro-injection pump 1.

[0034] In some embodiments, the free radical scavenger is selected from any one or a combination of 5,5-dimethyl-1-pyrrololine-N-oxide (DMPO), N-tert-butyl-α-phenylnitrone (PBN), 2-methyl-2-nitrosopropane (MNP), 5-tert-butoxycarbonyl-5-methyl-1-pyrrololine-N-oxide (BMPO), and 5-(diethoxyphosphoryl)-5-methyl-1-pyrrololine-N-oxide (DEPMPO).

[0035] The analytical method provided in this scheme, applicable to the redox radical generation mechanism, can be used to study the radical generation mechanism of redox initiation systems based on persulfates, hydrogen peroxide, sulfur-containing oxygen salts, and weakly bonded dissociated compounds or their organic derivatives. It confirms that the reaction in such systems occurs via a key intermediate, such as tBuO-OSO2 in the tBHP-SMBS redox system. - And gradually decompose to produce SO3· - The stepwise reaction mechanism of tBuO· (which in turn generates ·OH and ·CH3) free radicals, in which the common characteristics of the redox systems of persulfate and hydrogen peroxide are "rapid electron transfer + many short-lived reactive species", will produce ·OH and SO4· - Transient free radicals, accompanied by the formation of intermediates, can be directly identified by EPR combined with scavenging agents such as DMPO, while ATR can trace their decomposition products; the redox system of sulfur-containing oxygen salts will produce SO3· -Characteristic free radicals, and intermediates are mostly highly polar species, can be accurately identified by LC-MS; the weak bond breaking process of redox systems of weak bond dissociation compounds and their derivatives can be monitored by ATR to detect the attenuation of characteristic bond vibration peaks, and simultaneously correlated with free radical signals captured by EPR.

[0036] The oxidizing agent is one or a combination of tert-butyl hydroperoxide (tBHP), hydrogen peroxide (H2O2), potassium permanganate (KMnO4), and persulfate; the reducing agent is sodium metabisulfite (SMBS) and metal ions (such as Fe). 2+ Cu 2+ Sodium sulfite (Na2SO3), disulfides, dihalogens, alcohols, ethers, ketones, aldehydes, acids, and amines, or a combination thereof.

[0037] In some embodiments, the molar ratio of oxidant to reducing agent is 1:(0.1~10).

[0038] In some embodiments, ATR testing is performed using an in-situ attenuated total reflectance infrared spectroscopy device. The ATR testing employs a ZnS crystal, and the detection wavenumber range is 650–2000 cm⁻¹. -1 The background was pure water. The time resolution for EPR testing in the optimized in-situ electron paramagnetic resonance spectroscopy monitoring system was 10–20 ms, the scanning center magnetic field was 3300–3550 G, the scan width was 120–200 G, the receiver gain was 30–60 dB, and the microwave gain was 10–30 dB.

[0039] The overall approach to analyzing redox reaction pathways based on infrared spectroscopy and free radical data in this scheme is as follows:

[0040] First, a preliminary redox pathway is obtained through infrared spectral data. At this stage, the redox pathway from reactants to products is inferred mainly by the real-time changes in functional groups.

[0041] Then, EPR is used to test oxidants, reducing agents, and redox mixtures to obtain free radical data. At this point, the redox mechanism is refined from the free radical level, and the changes in functional groups are further subdivided into changes in free radicals. Then, the initially obtained redox pathway is optimized to obtain the free radical redox mechanism.

[0042] Then, the oxidant solution, reducing agent solution and free radical scavenger are injected into the optimized in-situ electron paramagnetic resonance spectroscopy monitoring system to obtain intermediate free radical data. Based on the intermediate free radical data, the free radical redox mechanism is optimized to obtain the redox reaction pathway.

[0043] Furthermore, separate oxidant solutions or reducing solutions and free radical scavengers are injected into an optimized in-situ electron paramagnetic resonance spectroscopy monitoring system to obtain control group free radical data. The control group free radical data and intermediate free radical data are compared to determine whether intermediates exist and the relationship between intermediates and free radicals. Then, based on the intermediate data, the free radical redox mechanism is optimized to obtain the redox reaction pathway.

[0044] Specifically, this scheme optimizes the in-situ electron paramagnetic resonance spectroscopy monitoring system to measure intermediate free radical data after a single mixing of oxidant, reductant, and a large excess of free radical scavenger. The intermediate free radical data represents the real-time change in the cumulative free radical signal value, where "cumulative free radical change = initially captured free radicals - natural quenching of captured free radicals + newly generated captured free radicals." If the intermediate free radical data shows a decrease in the free radical signal at a rate equal to the decrease rate of the control group's free radical signal, then there are no intermediates. If the decrease rate of the intermediate free radical data's free radical signal is slower than that of the control group's free radical signal, then the intermediates produce trace amounts of corresponding free radicals. If the intermediate free radical data shows an increase in the free radical signal, then the intermediates have produced a large number of corresponding free radicals, which is the main source of free radicals.

[0045] The control group of this scheme records the free radical data. After the free radicals are generated by photothermal exposure of a single oxidant or reductant, an appropriate amount of free radical scavenger is added and the free radical adduct is quenched by ordinary EPR test.

[0046] Once the presence of an intermediate is determined, relying solely on infrared spectroscopy data may not be sufficient to accurately confirm its structure. Therefore, the analytical method for redox-induced free radical generation mechanisms provided in this solution additionally includes the following steps:

[0047] Real-time sampling is performed during the reaction process to obtain full-process data. Analysis of this data identifies key nodes in the reaction process. Based on the molecular vibrational characteristic peaks of intermediates in the infrared spectral data corresponding to these key nodes, the properties of the intermediates are inferred. Based on these properties, offline identification of the intermediates using liquid chromatography-mass spectrometry (LC-MS) or gas chromatography-mass spectrometry (GC-MS) is performed to obtain their molecular structures. The redox reaction pathway is then refined based on the intermediate's molecular structure. In other words, this approach combines LC-MS, GC-MS, NMR, and an optimized in-situ electron paramagnetic resonance (EPR) spectroscopy monitoring system to prove the existence of intermediates and further refines the redox reaction pathway by supplementing the free radical acquisition mechanism surrounding the intermediates.

[0048] In this scheme, the "critical time nodes of the reaction process" refer to the moments when the characteristic peaks of intermediates detected in infrared spectral data appear or disappear, and / or the moments when the intensity of specific free radical signals detected in free radical data reaches its peak or undergoes significant changes, which are considered critical time nodes.

[0049] Furthermore, the choice between liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) is based on the properties of the intermediates in the infrared spectral data, where the intermediate properties include polarity, thermal stability, or molecular weight. Specifically, LC-MS is chosen for analysis when the intermediate is highly polar or thermally unstable, while GC-MS is used when the intermediate is a volatile small molecule.

[0050] Liquid chromatography-mass spectrometry combines chromatographic separation and mass spectrometry detection to separate and identify small components before and after the reaction of oxidants and reductants, and can be operated in both positive and negative ion modes.

[0051] In some embodiments, when using liquid chromatography-mass spectrometry (LC-MS) for analysis, the chromatographic separation can be performed on a C18 reversed-phase column (4.6 × 250 mm, 5 μm particle size) at a maintained column temperature of 40 °C. Furthermore, the mass spectrometry detection uses full scan mode with an m / z range of 50–700. The mobile phase consists of water (solvent A) and acetonitrile (solvent B), with a flow rate of 0.7 mL / min. -1 The injection volume was 8 μL. Gradient elution was used to optimize separation, with the initial proportion of mobile phase B at 5%, which was linearly increased to 95% within 15 min, then reequilibrated, and mass spectra were acquired in high-sensitivity ESI mode.

[0052] Gas chromatography-mass spectrometry (GC-MS) combines a gas chromatograph with a mass spectrometer equipped with an electron ionization (EI) source to identify oxidants, reductants, and volatile and semi-volatile compounds in redox reaction systems.

[0053] In some embodiments, when gas chromatography-mass spectrometry (GC-MS) is used for analysis, the mass spectrometer of the GC operates in scanning mode. Further, chromatographic separation is performed using an HP-5 MS inert capillary column (29.3 m × 0.25 mm inner diameter, 0.25 μm film thickness). The temperature program is set as follows: the column oven is initially maintained at 50 °C, then increased to 100 °C at a rate of 10 °C / min and held for 7 min, followed by further increases to 200 °C at a rate of 10 °C / min and held for 7 min.

[0054] Furthermore, after identifying the intermediate, this scheme can also use magnetic resonance spectroscopy to test the monomer conversion rate of free radical polymerization, in order to further verify that the free radicals generated by the intermediate are the same free radicals generated by the initiator contact reaction.

[0055] In some embodiments, after mixing the oxidant solution and the reducing agent solution for 10 minutes (at which point the free radicals generated by the contact reaction are basically quenched), the monomer is added (at which point the free radicals that promote monomer polymerization are free radicals derived from the decomposition of the intermediate), and the monomer conversion rate is observed using a magnetic resonance spectrometer.

[0056] In some embodiments, 1 H-NMR was performed using nuclear magnetic resonance spectroscopy, which can characterize the molecular structure of monomers and analyze the conversion rate of polymerization reactions initiated by redox initiation systems. Furthermore, 1 The proton detection frequency of H-NMR was 500 MHz, the spectrum was acquired at 25 °C, and standard one-dimensional proton acquisition parameters were used. Water peak suppression was employed when water was used as the solvent.

[0057] As mentioned earlier, the method for elucidating the redox free radical generation mechanism provided in this scheme can realize real-time, online, and dynamic monitoring and correlation analysis of the entire process from reactants, intermediates to free radicals and final products in the redox initiation system. This enables comprehensive mechanistic analysis from the molecular level to the free radical level, thereby elucidating the free radical generation pathway of the redox initiation system. Furthermore, by adjusting the ratio, concentration, and temperature parameters of oxidant / reductant, the law controlling the type and generation rate of free radicals can be explored, thereby regulating the polymerization reaction process and polymer properties.

[0058] Secondly, this solution provides a specific analytical method applicable to the mechanism of free radical generation from redox reactions, including the following steps:

[0059] Butyl hydrogen peroxide solution (tBHP), sodium metabisulfite (SMBS), and sodium 2-hydroxy-2-propanesulfonate (SAB) solution were injected into an in-situ attenuated total reflectance infrared spectroscopy device to obtain infrared spectral data of the reactants. The infrared spectral data of the reactants included reactants (such as tBHP, SMBS, SAB, SFS), intermediates, and products (such as tBuOH, HSO4). - Molecular vibrational characteristic peaks and their dynamic changes in acetone;

[0060] Butyl hydrogen peroxide solution (tBHP), sodium metabisulfite (SMBS), sodium 2-hydroxy-2-propanesulfonate (SAB) solution, and a free radical scavenger were injected into an optimized in-situ electron paramagnetic resonance spectroscopy monitoring system to obtain free radical data. The free radical data included the types of free radicals and the changes in free radical intensity over time. The free radical scavenger was selected from any one of DMPO, PBN, MNP, BMPO, and DEPMPO.

[0061] The reaction solutions before and after mixing were analyzed using GC-MS and LC-MS to separate and identify intermediates and final products inferred from infrared spectral data and free radical data.

[0062] In this embodiment, the intermediate inferred from infrared spectral data and free radical data is tBuO-OSO2. - Its further decomposition produces SO3· - Using one or more of the following free radicals—tBuO·, ·OH, and ·CH3—combined with dynamic data from Operando EPR and Operando ATR, the redox reaction is verified to occur via tBuO-OSO2. - The intermediate then decomposes stepwise to produce SO3· - The free radical generation pathway of tBuO· (which in turn generates ·OH and ·CH3).

[0063] In addition, in this embodiment, the molar ratio of oxidant to reductant (e.g., n) is changed systematically. tBHP : n SMBS By establishing the relationship between the types of free radicals and the proportions of reactants (ratios of 1:1, 2:1, 4:1), the regulatory rules of the reaction pathway are revealed. When n tBHP :n SMBS When the ratio is 1:1, SO3 is mainly generated. - Free radicals; when n tBHP : n SMBS When n = 4:1, mainly ·OH and ·CH3 free radicals are generated; when n tBHP : n SMBS When the ratio is 2:1, SO3· - ,·OH and ·CH3 free radicals.

[0064] It should be noted that the reaction can be carried out in solutions from room temperature to 65 °C, and is suitable for studying and optimizing sulfate radical-based reactions (SO4·4·4) - Advanced oxidation techniques using hydroxyl radicals (·OH) or hydroxyl radicals, as well as techniques for controlling the process of free radical polymerization and polymer properties.

[0065] To address the challenges of rapid and complex redox radical generation reactions and their initiation of polymerization processes, existing redox radical detection technologies suffer from limitations such as the inability to perform real-time in-situ monitoring, difficulty in capturing short-lived intermediates, inability to simultaneously correlate molecular structure and radical dynamics, and unclear understanding of reaction mechanisms. A novel solution is proposed, which offers the following characteristics and benefits:

[0066] 1. Real-time, online monitoring of redox initiation processes has been achieved, enabling the simultaneous acquisition of dynamic information on changes in molecular structure and the generation of free radicals, thus overcoming the time lag problem of traditional offline analysis methods;

[0067] 2. The tBuO-OSO2 was revealed and verified for the first time. - The presence of the intermediate and its mechanism of slow-release of free radicals provide direct experimental evidence for understanding the redox initiation mechanism;

[0068] 3. Through systematic research on the regulation of the ratio of oxidant / reductant on the types of free radicals, a predictable relationship was established from the composition of the initiation system to the characteristics of free radicals and then to the polymerization behavior, laying a theoretical foundation for the precise regulation of polymerization reactions;

[0069] 4. This method has good universality and is not only applicable to the tBHP / SMBS system, but can also be extended to the study of other redox initiation systems;

[0070] 5. It provides effective experimental guidance for the regulation of polymerization kinetics under low temperature conditions, and is particularly suitable for temperature-sensitive monomer polymerization systems. Attached Figure Description

[0071] Picture 1 It is a tBHP / SMBS (2:1, 25 °C, N2) reaction system operando ATR spectrum

[0072] Picture 2 For the tBHP / SMBS reaction system operando EPR spectrum;

[0073] Picture 3 GC-MS identification of intermediate tBuO-OSO2 - ;

[0074] Picture 4 LC-MS identification of intermediate tBuO-OSO2 - ;

[0075] Picture 5 For the tBHP / SAB (1:1, 25 °C, N2) reaction system operando ATR spectrum;

[0076] Picture 6 For the tBHP / SAB reaction system operando EPR spectrum;

[0077] Picture 7 The effect of molar ratio on the types and concentrations of free radicals generated by tBHP / SMBS;

[0078] Picture 8 The effect of molar ratio on the types and concentrations of free radicals generated by tBHP / SAB;

[0079] Picture 9 for operando Dynamic changes during the MAA polymerization process as measured by ATR spectra;

[0080] Picture 10 The effect of initiator concentration on the types and concentrations of free radicals generated by tBHP / SMBS;

[0081] Picture 11 The effect of initiator concentration on the types and concentrations of free radicals generated by tBHP / SAB;

[0082] Picture 12 A schematic diagram of the optimized in-situ electron paramagnetic resonance spectroscopy monitoring system;

[0083] Picture 13 This is a schematic diagram of the structure of an in-situ attenuated total reflectance infrared spectroscopy device.

[0084] In the diagram: 1. Micro-injection pump; 101. Oxidizing agent injection path; 102. Reducing agent injection path; 103. Free radical scavenger injection path; 104. T-joint; 105. Oxidizing-reducing agent mixing path; 106. Free radical scavenger mixing path; 107. U-shaped capillary reactor; 108. Waste liquid path; 109. Waste liquid tank; 110. Electromagnet and microwave bridge; 111. Resonant cavity; 112. EPR liquid nitrogen finger Dewar. ; 113. Liquid nitrogen bottle; 201. Water bath jacket; 202. Liquid phase ATR reaction cell; 203. ZnSe crystal; 204. Infrared spectrometer; 205. KBr spectrometer; 206. Spectroscopic analysis device; 207. Low temperature constant temperature water bath control device; 208. Airflow controller; 209. Temperature controller; 210. Thermocouple; 211. Stirrer; 212. Ventilation duct; 213. Valve; 214. Pressure sensor. Detailed Implementation

[0085] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0086] Unless otherwise specified, all materials, reagents and equipment used in the embodiments are commercially available products; and all methods used are prior art unless otherwise specified.

[0087] It should be noted that the in-situ electron paramagnetic resonance spectrum mentioned below ( operando To optimize in-situ electron paramagnetic resonance (EPR) spectroscopy, the content regarding "injecting oxidant and reducing agent solutions into a conventional in-situ EPR spectroscopy monitoring system for testing to obtain raw free radical data, and optimizing the functional group redox mechanism based on the raw free radical data to obtain the free radical redox mechanism" was not mentioned in the examples.

[0088] Example 1

[0089] Under ambient temperature (25 °C) aqueous phase conditions, tert-butyl hydroperoxide (tBHP) can form a highly efficient redox initiation system with sodium metabisulfite (SMBS).

[0090] In this embodiment, in-situ attenuated total reflectance infrared spectroscopy equipment was used respectively. operando ATR), in-situ electron paramagnetic resonance spectrum (ATR), operando EPR), for tBHP / SMBS(n tBHP : n SMBS = 2:1) The reaction process of the model system is monitored synchronously and in parallel in real time. The specific steps are as follows:

[0091] Step (1): Prepare 0.05 M tBHP aqueous solution and 0.025 M SMBS aqueous solution, respectively;

[0092] Step (2) involves injecting the two solutions into a precision injection system under the same initial conditions. operando ATR's reactor and equipment operando In the EPR reactor, two independent online monitoring systems were activated;

[0093] Step (3), through operando ATR spectroscopy tracks reactant consumption and product formation in real time, through operando EPR, combined with the free radical scavenger DMPO, captures the types of free radicals generated during the reaction in real time.

[0094] The reaction was carried out at 25 °C and normal pressure; operando Characteristic vibrational peaks monitored by ATR include: the ν(OO) peak of tBHP (843 cm⁻¹). -1 SMBS hydrolysis product HSO3 - Characteristic peak (1022 cm) -1 ), the ρ of the reaction product tBuOH s (CH3) peak (899 cm) -1 The ν(C=O) peak of acetone (1238 cm⁻¹) and acetone. -1 ); the operando EPR detects free radicals including SO3· - , ·OH and ·CH3.

[0095] Picture 1 and Picture 2 The reaction system of tBHP / SMBS (2:1, 25 °C, N2) was shown. operando ATR spectral dynamics and corresponding operando EPR spectrum. Operando ATR spectroscopy showed that tBHP (843 cm⁻¹) was present after the reaction began. -1 ) and HSO3 - (1022 cm -1 ) is rapidly consumed, while tBuOH (899 cm) -1 ) and acetone (1238 cm -1 It gradually comes into being. Operando EPR spectra showed that SO3· was mainly detected in the early stage of the reaction (0-10 min). - A free radical signal appears, followed by ·OH and ·CH3 free radical signals, which continue to increase. This was achieved by applying the same reaction conditions... operando ATR and operando Correlation analysis was performed on EPR time-series data, and the analysis results of the reaction solution were combined with those from GC-MS and LC-MS. Picture 4 (m / z 153 ions were detected). This example is the first experimental confirmation of the presence of tBuO-OSO2 in the tBHP / SMBS reaction system. - The study identified an intermediate and revealed the temporal relationship between its formation and the subsequent gradual generation of free radicals.

[0096] Example 2

[0097] Under ambient temperature (25 °C) aqueous phase conditions, tert-butyl hydroperoxide (tBHP) can form a highly efficient redox initiation system with sodium 2-hydroxy-2-propanesulfonate (SAB).

[0098] In this embodiment, in-situ attenuated total reflectance infrared spectroscopy equipment was used respectively. operandoATR and in-situ electron paramagnetic resonance spectroscopy operando EPR), for tBHP / SAB(n tBHP : n SAB = The reaction process of the 1:1 model system is monitored synchronously and in parallel in real time. The specific steps are as follows:

[0099] Step (1): Prepare 0.05 M tBHP aqueous solution and 0.05 M SAB aqueous solution, respectively;

[0100] Step (2) involves injecting the two solutions into a precision injection system under the same initial conditions. operando ATR's reactor and equipment operando In the EPR reactor, two independent online monitoring systems were activated;

[0101] Step (3), through operando ATR spectroscopy tracks reactant consumption and product formation in real time, through operando EPR, combined with the free radical scavenger DMPO, captures the types of free radicals generated during the reaction in real time.

[0102] The reaction was carried out at 25 °C and normal pressure; operando Characteristic vibrational peaks monitored by ATR include: the ν(OO) peak of tBHP (843 cm⁻¹). -1 ), characteristic peak of SAB (1030 cm⁻¹) -1 ), the ρ of the reaction product tBuOH s (CH3) peak (899 cm) -1 The ν(C=O) peak of acetone (1238 cm⁻¹) and acetone. -1 ); the operando EPR detects free radicals including SO₂ x · y- , ·OH and ·CH3.

[0103] Picture 5 and Picture 6 The reaction system of tBHP / SAB (1:1, 25 °C, N2) was shown. operando ATR spectral dynamics and corresponding operando EPR spectrum. Operando ATR spectroscopy showed that tBHP (843 cm⁻¹) was present after the reaction began. -1 ) and SAB (1030 cm) -1 ) is rapidly consumed, while tBuOH (899 cm) -1 ) and acetone (1238 cm -1 It gradually comes into being. OperandoEPR spectra showed that SO42- was the primary substance detected in the initial stage of the reaction (0-10 min). x · y- , ·OH and ·CH3 free radical signals.

[0104] Example 3

[0105] The molar ratio of oxidant to reducing agent has a decisive influence on the types of free radicals.

[0106] This embodiment investigates the regulatory effect of changing the molar ratio of tBHP to SMBS on the free radical generation pathway. The specific steps are as follows:

[0107] Step (1): Prepare three reaction systems with tBHP:SMBS molar ratios of 1:1, 2:1, and 4:1 respectively;

[0108] Step (2), using operando EPR monitoring of the types and signal intensity changes of free radicals generated in different proportion systems within the first 30 minutes of the reaction;

[0109] Step (3), combined with operando ATR spectroscopic analysis of reactant consumption rate and intermediate formation.

[0110] All reactions were carried out in an aqueous solution at 25 °C and pH 7.0; the total concentration of tBHP and SMBS was 0.14 M; and the concentration of the free radical scavenger DMPO was 50 mM.

[0111] Operando EPR experimental results show that when n tBHP :n SMBS When the ratio is 1:1 (i.e., excess reducing agent), the EPR spectrum shows strong SO3· - A sextuplet signal was observed, while the signals for ·OH and ·CH3 were weak; when n tBHP :n SMBS When the ratio is 4:1 (oxidant in excess), the main detected signals are the ·OH quartet and the ·CH3 sextet, and SO3· - The signal almost disappeared; when n tBHP :n SMBS When the stoichiometric ratio is 2:1, SO3· - The example demonstrates that the types of free radicals can be precisely controlled by simply adjusting the oxidant / reducing agent ratio, providing a theoretical basis for directed polymerization reactions.

[0112] Example 4

[0113] The molar ratio of oxidant to reducing agent has a decisive influence on the types of free radicals.

[0114] This embodiment studies the regulatory effect of changing the molar ratio of tBHP to SAB on the free radical generation pathway. The specific steps are as follows:

[0115] Step (1): Prepare three reaction systems with tBHP: SAB molar ratios of 0.5:1, 1:1, and 2:1 respectively;

[0116] Step (2), using operando EPR monitoring of the types and signal intensity changes of free radicals generated in different proportion systems within the first 30 minutes of the reaction;

[0117] Step (3), combined with operando ATR spectroscopic analysis of reactant consumption rate and intermediate formation.

[0118] All reactions were carried out in an aqueous solution at 25 °C and pH 7.0; the total concentration of tBHP and SAB was 0.14 M; and the concentration of the free radical scavenger DMPO was 50 mM.

[0119] Operando EPR experimental results show that when n tBHP :n SAB When the ratio is 1:2 (i.e., excess reducing agent), the EPR spectrum shows strong SO₂. x · y- A sextuplet signal was observed, while the signals for ·OH and ·CH3 were weak; when n tBHP :n SAB When the ratio is 2:1 (oxidant in excess), the main detected signals are the ·OH quartet and the ·CH3 sextet. x · y- The signal gradually increases in strength from weak; when n tBHP :n SAB When the stoichiometric ratio is 1:1, SO₂ is present in the system simultaneously. x · y- The example demonstrates that the types of free radicals can be controlled by simply adjusting the oxidant / reducing agent ratio, providing a theoretical basis for directed polymerization reactions.

[0120] Example 5

[0121] The optimized tBHP / SMBS initiation system was applied to the polymerization reaction of methacrylic acid (MAA) to verify the effect of SO3· - The initiation efficiency of free radicals on hydrophilic monomers is determined through the following steps:

[0122] Step (1), mix tBHP and SMBS with n tBHP :n SMBSMix in a 2:1 ratio and allow to react for 10 minutes.

[0123] Step (2): Add MAA monomer to the initiation system to make the monomer concentration 1 M;

[0124] Step (3), through operando ATR monitoring showed the characteristic peak of MAA (ν(C=O) at 1722 cm⁻¹). - ¹,ν(C=C)at1637 cm - The intensity change of ¹) was used to calculate the monomer conversion rate in conjunction with ¹H-NMR.

[0125] The polymerization reaction was carried out at 25 °C under a N2 atmosphere; operando The ATR spectrum was acquired every 2 minutes; the remaining monomer amount was determined by the ¹H-NMR using the internal standard method.

[0126] Picture 9 Showing the MAA aggregation process operando Dynamic changes in the ATR spectrum. As the reaction proceeds, the characteristic peak of MAA at ν(C=C) (1637 cm⁻¹) increases. -1 The intensity gradually decreases, while the characteristic peak of the carboxyl group in polymer PMAA (1722 cm⁻¹) remains constant. -1 The initiation process continued to enhance and exhibited a redshift. ¹H-NMR analysis showed that this initiation system achieved a MAA conversion rate of 5.89% within 3 hours, significantly higher than the conversion rate (<1%) of traditional thermal initiation systems at the same temperature. This example confirms the effectiveness of SO3· - Free radicals have excellent initiation activity for hydrophilic monomers, providing a new approach for low-temperature aqueous phase polymerization.

[0127] Example 6

[0128] The effects of temperature and initiator concentration on the performance of the tBHP / SMBS initiation system were investigated using the following steps:

[0129] Step (1): Free radical detection of the tBHP / SMBS redox initiation system was performed at 25 °C, 45 °C and 65 °C respectively;

[0130] Step (2): Adjust the total concentration of the initiator (0.028 M, 0.14 M, 0.28 M) and study its effect on free radicals in the tBHP / SMBS redox initiation system;

[0131] Step (3), through operando EPR quantitative analysis of SO3· under different conditions - The kinetics of free radical generation.

[0132] The initiator concentration was fixed at 0.14 M in the temperature experiment; the concentration experiment temperature was fixed at 25 °C; and the molar ratio of oxidant to reductant was fixed at n. tBHP :n SMBS = 2: 1.

[0133] Operando EPR experimental results showed that when the temperature increased from 25 °C to 65 °C, the types of free radicals remained unchanged, all being SO3· - The free radical activity is highest at 45 °C. Picture 10 The results showed that when the initiator concentration increased from 0.028 M to 0.28 M, the type of free radical remained unchanged, all being SO3· - The free radical activity increased by approximately 8 times. In conclusion, appropriately increasing the temperature and concentration can significantly enhance SO3· - The free radical signal intensity was measured, and the free radical generation rate was positively correlated with the polymerization rate. This example provides experimental basis for optimizing the process parameters of the redox initiation system.

[0134] Example 7

[0135] The effects of temperature and initiator concentration on the performance of the tBHP / SAB initiation system were investigated using the following steps:

[0136] Step (1): Free radical detection of the tBHP / SAB redox initiation system was performed at 25 °C, 45 °C and 65 °C respectively.

[0137] Step (2): Adjust the total concentration of the initiator (0.028 M, 0.14 M, 0.28 M) and study its effect on free radicals in the tBHP / SAB redox initiation system;

[0138] Step (3), through operando EPR quantitative analysis of SO under different conditions x · y- The kinetics of free radical generation.

[0139] The initiator concentration was fixed at 0.14 M in the temperature experiment; the concentration experiment temperature was fixed at 25 °C; and the molar ratio of oxidant to reductant was fixed at n. tBHP :n SAB = 1: 1.

[0140] Operando EPR experimental results showed that the types of free radicals changed when the temperature increased from 25°C to 65°C, and the free radical activity was highest at 45°C. Picture 11 The results showed that when the initiator concentration increased from 0.028 M to 0.28 M, the type of free radical remained unchanged, all being SO₂.x · y- The free radical activity increased by approximately four times. In summary, both appropriately increasing the temperature and increasing the concentration can alter SO₂ activity. x · y- Free radical signal intensity. This example provides experimental basis for optimizing process parameters of the redox initiation system.

[0141] Example 8

[0142] The method of this invention was applied to study the effect of the molar ratio of oxidant to reducing agent on the monomer polymerization conversion rate, in order to verify the practicality of this method in guiding the optimization of polymerization processes. The specific steps are as follows:

[0143] Step (1): Configure three redox initiation systems with molar ratios of tBHP to SMBS of 1:1, 2:1 and 4:1, respectively;

[0144] Step (2): Mix each group of initiation systems with the methacrylic acid (MAA) monomer solution to make the initial monomer concentration 1M, and initiate the polymerization reaction under constant temperature conditions of 25°C;

[0145] Step (3): During the polymerization reaction, samples are taken periodically and... 1 H-NMR accurately determines the conversion rate of monomers;

[0146] Step (4), combined with operando EPR analysis results on the types of free radicals generated by the corresponding initiation system, and the relationship between the types and proportions of free radicals and the final monomer conversion rate.

[0147] In each group of experiments, the total concentrations of tBHP and SMBS remained constant; the NMR tests used terephthalaldehyde as an internal standard for quantitative calculation.

[0148] Table 1 shows the change in MAA monomer conversion over time under different tBHP / SMBS molar ratios. Experimental results indicate that when n tBHP :n SMBS When the ratio is 1:1, the polymerization reaction achieves the highest final conversion rate, reaching 5.89%, within 3 hours. operando EPR analysis showed that the system mainly produced SO3· - Free radicals indicate SO3· - It exhibits higher initiation efficiency for MAA monomers. With increasing oxidant ratio (2:1 and 4:1), the monomer conversion rate decreases significantly, which is related to... operandoThe results obtained by EPR detection of the transformation of free radical types to ·OH and ·CH3 are consistent. This embodiment demonstrates that the method provided by the present invention can provide direct experimental evidence and theoretical guidance for accurately optimizing the initiation system ratio and thus maximizing monomer conversion rate by analyzing the free radical generation pathway.

[0149] Example 9

[0150] The method of this invention was applied to study the effect of the molar ratio of oxidant to reducing agent on the monomer polymerization conversion rate, in order to verify the practicality of this method in guiding the optimization of polymerization processes. The specific steps are as follows:

[0151] Step (1), configure tBHP and SMBS n tBHP :n SMBS = 2:1 redox initiation system;

[0152] Step (2): Mix each group of initiation systems with the hydroxyethyl methacrylate (HEMA) monomer solution to make the initial monomer concentration 1 M, and initiate the polymerization reaction under constant temperature of 25 °C;

[0153] Step (3): During the polymerization reaction, samples are taken periodically and... 1 H-NMR accurately determines the conversion rate of monomers;

[0154] Step (4), combined with operando EPR analysis results on the types of free radicals generated by the corresponding initiation system, and the relationship between the types and proportions of free radicals and the final monomer conversion rate.

[0155] In each group of experiments, the total concentrations of tBHP and SMBS remained constant; the NMR tests used terephthalaldehyde as an internal standard for quantitative calculation.

[0156] 1 H-NMR results show that when n tBHP :n SMBS When the ratio is 2:1, the conversion rate of HEMA is about 30 times higher than that of MAA.

[0157] Table 1 below shows the change in MAA / HEMA monomer conversion over time under different tBHP / SMBS molar ratios:

[0158] Table 1. Variation of MAA / HEMA monomer conversion rate over time under different tBHP / SMBS molar ratios.

[0159]

[0160] Those skilled in the art should understand that the technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments have been described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0161] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for analyzing a redox radical generation mechanism and its initiation of polymerization, characterized by, The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group.

2. The analytical method suitable for redox-generated radical mechanism and its initiation polymerization according to claim 1, characterized in that, The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group.

3. The analytical method suitable for redox-generated radical mechanism and its initiation of polymerization according to claim 2, characterized in that, The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group.

4. The analytical method suitable for redox-generated radical mechanism and its initiation polymerization according to claim 3, characterized in that, The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group.

5. The analytical method suitable for redox-generated radical mechanism and its initiated polymerization according to claim 1, characterized in that, The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of a functional group. The application relates to a method for obtaining an oxidation-reduction reaction path of 6. The analytical method suitable for redox-generated radical mechanism and its initiated polymerization according to claim 1, wherein, The radical scavenger is selected from any one or a combination of 5,5-dimethyl-1-pyrroline-N-oxide, N-tert-butyl-alpha-phenyl nitrone, 2-methyl-2-nitrosopropane, 5-tert-butoxycarbonyl-5-methyl-1-pyrroline-N-oxide, and 5-(diethoxyphosphoryl)-5-methyl-1-pyrroline-N-oxide.

7. The analytical method suitable for redox-generated radical mechanism and its initiated polymerization according to claim 1, characterized by, The molar ratio of the oxidant to the reducing agent is 1: (0.1-10).

8. The analytical method suitable for redox-generated radical mechanism and its initiated polymerization according to claim 1, wherein, Real-time sampling is performed during the reaction process to obtain reaction process data, key nodes of the reaction process are obtained by analyzing the reaction process data, the properties of intermediates are inferred based on the molecular vibration characteristic peaks of the intermediates in the infrared spectrum data corresponding to the key nodes, the molecular structures of the intermediates are obtained by off-line identification of the intermediates based on the properties of the intermediates by using liquid chromatography-mass spectrometry or gas chromatography-mass spectrometry technology, and the oxidation-reduction reaction path is perfected based on the molecular structures of the intermediates.

9. The analytical method suitable for redox-generated radical mechanism and its initiated polymerization according to claim 1, wherein, The properties of the intermediates are polarity, thermal stability, or molecular weight information, when the polarity of the intermediates is large or the intermediates are not thermally stable, liquid chromatography-mass spectrometry technology is selected for analysis, and when the intermediates are volatile small molecules, gas chromatography-mass spectrometry technology is used for analysis.

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