Method for detecting the quality of a photoinitiator and use thereof

Abstract

The application provides a method for detecting the quality of a photoinitiator and application thereof, and comprises sample grouping and curing treatment before testing, time synchronization calibration of curing state, continuous acquisition and analysis of spectrum data. By introducing infrared spectrum analysis and setting a safety threshold, a curing reaction curve of the photoinitiator is constructed, and a test variable is introduced to quantify the reaction behavior of the photoinitiator. According to the unit time change rate of the test variable, the initiation efficiency and stability of the photoinitiator are determined, and then the quality of the photoinitiator is evaluated. The method can realize the standardized comparison of different batches or different types of photoinitiators, and is suitable for the fields of polymer material processing, coating formula optimization and light curing product quality control, and has good adaptability and practical value.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of product physical and chemical property detection, and particularly relates to a method for detecting the quality of a photoinitiator and application thereof. BACKGROUND

[0002] As a key additive component in radiation curing systems, photoinitiators are widely used in fields such as photocurable coatings, photosensitive resins, printing inks, and 3D printing materials. Their main function is to generate free radicals or cations under ultraviolet or visible light irradiation, thereby initiating the polymerization reaction of monomers or oligomers and achieving rapid curing. Due to the diverse types and complex structures of photoinitiators, their quality directly affects the curing speed, film-forming performance, mechanical properties, and durability of photocured products.

[0003] Currently, the evaluation of photoinitiator quality mainly relies on technical indicators provided by raw material suppliers, such as purity, absorption wavelength, and molar absorption coefficient. Although these indicators can be used as a reference, they do not comprehensively reflect the initiation activity and stability of photoinitiators in actual use. Meanwhile, conventional detection methods such as high-performance liquid chromatography (HPLC), ultraviolet-visible spectroscopy analysis (UV-Vis), and mass spectrometry can qualitatively and quantitatively analyze the composition and content of photoinitiators, but they cannot effectively evaluate their initiation efficiency or activity state in specific systems.

[0004] In addition, photoinitiators are prone to degradation reactions such as photooxidation, hydrolysis, and pyrolysis during storage, transportation, and use. These changes can lead to a decrease in their activity and initiation ability, thereby affecting the performance of the final product. However, there is still a lack of a method that can quickly and accurately evaluate the quality changes of photoinitiators, especially their initiation performance in specific systems.

[0005] Therefore, there is an urgent need to develop a photoinitiator quality detection method based on actual application scenarios, which can consider multiple factors such as initiation activity, stability, and environmental adaptability, and provide reliable basis for the development and quality control of photocured materials. SUMMARY

[0006] To solve the above problems, the present application provides a method for detecting the quality of a photoinitiator, comprising the following steps:

[0007] S1, preparation before testing: preparing multiple test samples from the sample to be tested, dividing the sample to be tested into a target sample group and a comparison sample group, and using inductive heating method to cure the photoinitiator to form a cured film on the surface of the sample; wherein the target sample group uses the photoinitiator to be tested, and the comparison sample group uses one or more photoinitiators with stable performance;

[0008] S2, synchronously calibrating the curing state: using a time synchronization calibration method, calibrating the curing degree of each sample cured film, so that each sample cured film is in a "not completely cured stage" below the preset curing degree target;

[0009] S3, synchronously collecting spectrum data: under the calibrated "not completely cured stage", respectively, the target sample group and the comparative sample group are subjected to infrared spectrum test, and spectrum data is continuously collected until the state of the sample cured film reaches or exceeds the preset curing degree target;

[0010] S4, spectrum data analysis: comparing the infrared spectrum data of the target sample group and the comparative sample group under the same curing stage, analyzing the dynamic reaction behavior of the to-be-tested photoinitiator in the curing process of the target sample group, determining the initiation efficiency, and determining the quality of the initiator based on the initiation efficiency;

[0011] As a preferred technical solution, in the step S2, the time synchronization calibration method specifically refers to: obtaining spectrum data of the photoinitiator by a real-time infrared spectrum analysis method, the curing stage is calibrated according to a real-time time axis, and the curing time of the photoinitiator is taken as the abscissa, the material change caused by the to-be-tested photoinitiator in the cured film before and after curing is analyzed, so as to calibrate the spectrum response curve in the initiation reaction process, and determine the stage with positive reaction curve slope as the characteristic mark of the active initiation reaction stage.

[0012] As a preferred technical solution, in the step S2, when the infrared spectrum is obtained for the first time, the spectrum data at this time is taken as a reference, and the corresponding time is defined as "0" point; after the cured film of the initiator is completely cured, the last spectrum is obtained, and the time corresponding to this moment is defined as the curing time ; the curing reaction curve of the initiator in the interval is , and the corresponding curing time interval is called the full curing interval; in the full curing interval, the material structure of the initiator and the test sample coating material changes, and a test variable is introduced, the test variable is a characterization parameter for characterizing the chemical reaction behavior of the initiator in the curing process; the test variable is divided into the test variable of the initiator and the generated variable of the initiator, satisfying the function relationship: and , wherein, is time.

[0013] As a preferred technical solution, the test variable of the initiator and the generated variable of the initiator are one of the following combinations:

[0014] Q1. Test Variables Refers to the intensity of the spectral response: This indicates the intensity of the absorption peak of the initiator at a specific wavelength. This indicates the intensity of the absorption peak corresponding to the product structure during the curing process;

[0015] Q2, Test Variables Refers to monomer conversion rate: Indicates the degree of reactivity of the original monomer. Indicates the degree of conversion of the generated polymer;

[0016] Q3. Test Variables Refers to the concentration of photoinitiator: Indicates the effective concentration of the photoinitiator. This indicates the cumulative concentration of the reacted portion.

[0017] As a preferred technical solution, a safety threshold is introduced in step S2. The security threshold The range of absorption intensity changes obtained from infrared spectroscopy is used to characterize the active boundary of the photoinitiator during the curing process; among which, Indicates the minimum effective response threshold. This indicates the maximum acceptable response limit. and The experimental setup was compared using the spectrum of a standard initiator; the initiation reaction curve was obtained throughout the entire curing process. With safety threshold The common area is the effective fixed area. , wherein This represents the onset time of the photoinitiator-initiated reaction. The end time of the photoinitiator-initiated reaction .

[0018] As a preferred technical solution, in step S3, the initiation reaction curves of the target sample group and the control sample group are compared. With safety threshold public area Alignment is performed to ensure that the common intervals intersect the horizontal axis at the same point. The common intervals are determined by the leftmost and rightmost intersections with the horizontal axis. This makes the concentration curves of reactants and initiating membrane substances in the common common region comparable between the target sample group and the control sample group.

[0019] As a preferred technical solution, in step S4, determining the initiation efficiency specifically refers to: based on and The changes in the initiator determine its initiation efficiency.

[0020] As a preferred technical solution, in step S4, according to and The determination of the initiation efficiency of the initiator based on the changes in the initial value specifically refers to: using the initial value and Using this as a baseline, calculate the test variables. The change value is calculated using the following formula:

[0021] ;

[0022] ;

[0023] in, and Let these represent the test variable of the initiator and the generation variable of the initiator, respectively, from the initial time to... The change per unit of time at any given moment.

[0024] As a preferred technical solution, in step S4, determining the initiator quality based on initiation efficiency specifically refers to: calculating the target sample group and the control sample group. and The value is used to determine whether the initiation efficiency and stability of the target sample group meet the standards. The judgment criteria are as follows:

[0025] T1, if the target sample group The value was higher than that of the control sample group. If the value is less than the target sample group's initiation efficiency, then the initiation efficiency is deemed substandard.

[0026] T2, if the target sample group The value is equal to or lower than that of the control sample group. Value, and the target sample group The value is equal to or higher than that of the control sample group. If the value is [value], it is determined that the initiation efficiency and stability of the target sample group meet the standards.

[0027] T3, if the target sample group The value is equal to or lower than that of the control sample group. Value, but the target sample group The value was lower than that of the control sample group. If the value is zero, it is determined that the initiation efficiency of the target sample group meets the standard, but the stability does not.

[0028] This invention also provides the application of the method for detecting the quality of photoinitiators in the quality inspection of photoinitiator finished products.

[0029] Beneficial effects:

[0030] The present invention provides a method for detecting the quality of photoinitiators, which has the following beneficial effects:

[0031] 1. Improve the scientific rigor and practical applicability of the test. This method prepares samples by using the photoinitiator to be tested and a known comparative initiator as raw materials, and then performs curing treatment under the same conditions. This effectively controls variables, improves the accuracy and reproducibility of the test results, and can truly reflect the reactivity of the initiator in actual use.

[0032] 2. Enables dynamic analysis of the entire curing process. By employing synchronous calibration, infrared spectral data is collected during the stage before the photoinitiator is fully cured. This avoids the limitations of traditional detection methods that only focus on the curing endpoint, and facilitates the discovery of changes in the initiator's activity during the early reaction process, thus enhancing a comprehensive understanding of the reaction behavior.

[0033] 3. Establish a full-process variation model of curing behavior. This invention sets curing time as the horizontal axis and introduces time variation parameters representing reactivity and product formation, thereby achieving a quantitative expression of initiator reaction efficiency. It allows for a direct assessment of the initiator's performance level based on the reaction changes per unit time.

[0034] 4. Applicable to quality grading and rapid screening of photoinitiators. This method can not only identify whether the initiation efficiency meets the standard, but also determine its performance stability by the combination of change rates. It is particularly suitable for promotion and application in new material development, formulation optimization and raw material acceptance, and has good versatility and industrialization value.

[0035] In summary, the detection method proposed in this invention has advantages such as high detection accuracy, comprehensive process analysis, clear quantitative indicators, and clear judgment criteria, and can provide an efficient, reliable, and systematic solution for the quality evaluation of photoinitiators. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the method flow of the present invention. Detailed Implementation

[0037] To enhance understanding of the present invention, the present invention will be further described in detail below with reference to embodiments. These embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0038] Example 1

[0039] according to Figure 1 As shown, this embodiment provides a method for detecting the quality of a photoinitiator, including the following steps:

[0040] S1, test preparation: prepare multiple test samples from the sample to be tested, divide the sample to be tested into a target sample group and a comparative sample group, and use inductive heating method to solidify the initiator to form a solidified film on the surface of the sample; wherein the target sample group uses the light initiator to be tested, and the comparative sample group uses one or more light initiators with known stable performance.

[0041] S2, synchronous calibration of solidification state: using a time synchronization calibration method, the solidification degree of each sample solidified film is calibrated, so that each sample solidified film is in the "incomplete solidification stage" below the preset solidification degree target.

[0042] The time synchronization calibration method specifically refers to: obtaining the spectrum data of the light initiator by real-time infrared spectrum analysis method, the solidification stage is calibrated according to the real-time time axis, and the solidification time of the light initiator is taken as the abscissa, the material changes caused by the light initiator in the solidified film before and after solidification are analyzed, so as to calibrate the spectrum response curve in the initiation reaction process, and determine the stage with positive reaction curve slope as the characteristic mark of the active stage of the initiation reaction.

[0043] Introducing a safety threshold , the safety threshold is the absorption intensity change range obtained by infrared spectrum method, which is used to represent the activity boundary of the light initiator in the solidification reaction process; wherein, represents the minimum effective reaction response threshold, represents the highest acceptable response upper limit, and The spectrum comparison experiment of the standard initiator is preset; in the whole solidification interval, the common interval of the initiation reaction curve and the safety threshold is the effective solidification interval , wherein the is the starting time of the initiation reaction of the light initiator, is the end time of the initiation reaction of the light initiator .

[0044] When the infrared spectrum is obtained for the first time, the spectrum data of this time is taken as the reference, and the corresponding time is defined as "0" point; after the solidified film of the initiator is completely solidified, the last spectrum is obtained, and the time corresponding to this time is defined as the solidification time ; the solidification reaction curve of the initiator in the interval is curve, and the corresponding solidification time interval is called the whole solidification interval; in the whole solidification interval, the material structure of the initiator and the test sample coating material changes, and a test variable is introduced, and the test variable characterization parameters for characterizing the chemical reaction behavior of the initiator in the curing process; test variables Test variables of the initiator and generation variables of the initiator , satisfy the function relationship: and , wherein, is time.

[0045] Test variables of the initiator and generation variables of the initiator are one of the following combinations:

[0046] Q1, test variable refers to the spectral response intensity: represents the absorption peak intensity of the initiator to a specific waveband, represents the intensity of the corresponding absorption peak of the product structure in the curing process;

[0047] Q2, test variable refers to the monomer conversion rate: represents the degree of reactivity of the original monomer, represents the conversion degree of the generated polymer;

[0048] Q3, test variable refers to the photoinitiator concentration: represents the effective concentration of the photoinitiator, represents the cumulative generation concentration of the reacted part.

[0049] S3, synchronously collect spectral data: under the calibrated "incomplete curing stage", respectively, the target sample group and the comparative sample group are tested by infrared spectrum, and the spectral data is continuously collected until the state of the sample curing film reaches or exceeds the preset curing degree target.

[0050] Align the initiation reaction curves of the target sample group and the comparative sample group with the common interval of the safety threshold , ensure that the intersection of the common interval and the horizontal axis is the same, and determine the common common interval with the leftmost intersection with the horizontal axis and the rightmost intersection with the horizontal axis , so that the concentration curves of the reactants and the initiator film substances in the target sample group and the comparative sample group in the common common interval have comparability.

[0051] S4, spectral data analysis: compare the infrared spectral data of the target sample group and the comparative sample group at the same curing stage, analyze the dynamic reaction behavior of the photoinitiator to be tested in the target sample group in the curing process, determine the initiation efficiency, and determine the initiator quality based on the initiation efficiency. ​

[0052] According to and , the initiation efficiency of the initiator refers to the change value of the test variable and , which is calculated based on the initial value , and the calculation formula is:

[0053] ;

[0054] ;

[0055] wherein, and respectively represent the change amount per unit time of the test variable of the initiator and the generation variable of the initiator from the initial time to .

[0056] Based on the initiation efficiency, the quality of the initiator is determined by calculating the and values of the target sample group and the comparison sample group, and determining whether the initiation efficiency and stability of the target sample group meet the standards, and the determination conditions are:

[0057] T1, if the value of the target sample group is higher than the value of the comparison sample group, it is determined that the initiation efficiency of the target sample group does not meet the standards;

[0058] T2, if the value of the target sample group is equal to or lower than the value of the comparison sample group, and the value of the target sample group is equal to or higher than the value of the comparison sample group, it is determined that the initiation efficiency of the target sample group meets the standards and the stability meets the standards;

[0059] T3, if the value of the target sample group is equal to or lower than the value of the comparison sample group, but the value of the target sample group is lower than the value of the comparison sample group, it is determined that the initiation efficiency of the target sample group meets the standards but the stability does not meet the standards.

[0060] Example Two

[0061] The present embodiment discloses a detection method for evaluating the quality of a photoinitiator, which is characterized by constructing a curing behavior determination mechanism based on infrared spectrum analysis, and realizing comprehensive judgment of the initiation efficiency and stability of the photoinitiator by comparing the reaction behavior curves of different sample groups. The method comprises the following steps:

[0062] S1, test sample preparation stage:

[0063] A plurality of test samples are prepared from the photoinitiator sample to be tested, and the samples are divided into a "target sample group" and a "comparison sample group" according to the principles of experimental design.

[0064] The target sample group uses the photoinitiator to be tested, and the comparison sample group uses one or more standard photoinitiators with known performance and stable initiation behavior as reference materials. Subsequently, the above two groups of samples are treated using inductive heating method, so that the photoinitiators form a cured film on the surface of the respective samples.

[0065] S2, synchronous calibration stage of the curing state:

[0066] A synchronous calibration method based on a time axis is used to standardize the curing film reaction process of the two groups of samples. The specific steps include:

[0067] The infrared spectroscopy technique is used to dynamically and real-time detect the curing process of the photoinitiator, and record the spectral changes at different time points;

[0068] The starting point of the curing reaction (the time of obtaining the first spectrum) is set as time "0", and the moment when the curing is finally completed is recorded as time "T", thereby constructing a full-process curing reaction curve of the photoinitiator , which reflects the reaction behavior of the photoinitiator in the time interval;

[0069] A safety threshold interval is introduced in the reaction process to characterize the effectiveness of the photoinitiator reaction , where:

[0070] represents the minimum effective spectral response threshold, represents the highest acceptable response upper limit, both of which are set in advance through response spectrum comparison experiments of standard photoinitiators;

[0071] The time interval where intersects with the safety threshold is defined as the effective curing interval , i.e. the time range from the beginning of the initiation reaction (t ) to the termination of the reaction (t );

[0072] The reaction behavior in this interval is determined as the effective comparison object for subsequent analysis, so as to realize the spectrum data acquisition of different samples under comparable conditions.

[0073] In this process, a test variable is introduced to quantify the initiation reaction behavior, including the following two types of parameters:

[0074] Initiator test variable : Reflects the reaction behavior of the initiator itself;

[0075] Initiator generation variable : Characterizes the formation of reaction products;

[0076] Test variable The value of the test variable can be one of the following three types:

[0077] Q1: Take the intensity of a specific absorption peak in infrared spectrum as a characteristic quantity, represents the intensity of the initiator absorption peak, represents the intensity of the product absorption peak;

[0078] Q2: Take the monomer conversion rate as a characteristic quantity, represents the degree of unreacted monomer conversion, represents the degree of polymer generation;

[0079] Q3: Take the photoinitiator concentration as a characteristic quantity, represents the remaining effective concentration, represents the cumulative reaction concentration.

[0080] S3, spectrum data collection stage:

[0081] Under the calibrated "incomplete curing stage", the target sample group and the comparative sample group are respectively subjected to continuous infrared spectrum collection, and the spectrum data changes in the effective curing interval are recorded. This stage requires:

[0082] The curing reaction curves of the two groups of samples are uniformly aligned to ensure that the starting points and the ending points of the two groups of spectra on the time axis are consistent, so that the spectrum data in the common interval is comparable;

[0083] All spectrum collection is carried out at equal intervals to ensure consistent sampling density and time granularity;

[0084] The trends of and varying with time are dynamically recorded during the collection process to form a complete reaction behavior data sequence.

[0085] S4, spectrum data analysis and quality judgment stage:

[0086] The spectrum data of the target sample group and the comparative sample group in the interval is subjected to mathematical processing and difference analysis. The specific steps are as follows:

[0087] Take time as a variable, respectively calculate the initiator test variable and generation variable rate of change per unit time , Its definition is as follows:

[0088] ;

[0089] ;

[0090] The above Δ values ​​represent the consumption rate of the initiator and the product formation rate during the curing process, respectively;

[0091] Comparison of target sample group and control sample group , The value is used to determine the quality of the photoinitiator to be tested, and the following rules are applied:

[0092] T1, Insufficient initiation efficiency: If the target sample group The value is higher than that of the control sample group, indicating that the initiator is consumed too quickly but fails to be converted into enough product, and the initiation efficiency is not up to standard.

[0093] T2, efficiency, and stability are all satisfactory: If the target sample group The value is equal to or lower than that of the control group, and A value equal to or higher than that of the control group indicates that the initiator reaction process is stable and both initiation efficiency and stability are qualified.

[0094] T3. Efficiency is acceptable, but stability is insufficient: If Lower than the control group, but The efficiency was also lower than that of the control group, indicating that the initiation efficiency was acceptable, but the product fluctuated greatly and the stability did not meet the standard.

[0095] Ultimately, the above-mentioned judgment rules can be used to comprehensively assess the quality of photoinitiators, making them applicable to various application scenarios such as R&D verification, new product screening, and batch stability assessment.

[0096] Example 3

[0097] This embodiment aims to verify the ability of the detection method to quantitatively evaluate the initiation efficiency and stability of photoinitiators. Specifically, commercially available photoinitiators A (target sample group) and B (comparison sample group) with clearly defined models were selected, and infrared spectral monitoring and data analysis were performed under the same experimental conditions.

[0098] S1: Sample preparation for testing:

[0099] Photoinitiator A (target sample group): Irgacure® 819 produced by BASF, Germany, with chemical name Bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, CAS number 162881-26-7, purity ≥ 99%, light yellow powder, main absorption wavelength 295 nm and 370 nm, suitable for UV-A region free radical initiation.

[0100] Photoinitiator B (comparative sample group): Irgacure® 1173 produced by Ciba, with chemical name 2-Hydroxy-2-methyl-1-phenyl-propan-1-one, CAS number 7473-98-5, main absorption wavelength 254 nm and 320 nm.

[0101] Both groups of samples were based on epoxy acrylate resin E-600, with 2.0 wt% of initiator added, and magnetically stirred for 30 minutes to completely dissolve.

[0102] Subsequently, the resin mixture was drop-coated on the surface of KBr infrared sample sheet to form a film layer with a thickness of 60±5 μm, and the number of standby samples was 5 for each group.

[0103] S2: synchronous calibration of curing state:

[0104] The sample sheet was maintained at a constant temperature of 45°C for curing using a UV LED irradiation system (main wavelength 365 nm, intensity 100 mW / cm 2 ) combined with an induction heating plate.

[0105] Bruker Tensor II Fourier transform infrared spectrometer (FTIR) was used to collect the initiation reaction spectrum in real time, with a sampling interval of 3 seconds and a duration of 180 seconds.

[0106] Two key wavebands were selected in the spectrum analysis:

[0107] C=O stretching vibration absorption peak (1720 cm -1 ): used to represent the residual absorption of photoinitiator;

[0108] C–O–C peak (1165 cm -1 ): used to represent the generation of polymerization product.

[0109] The first spectrum collection was defined as time t0=0 seconds, and the end of curing was t_end=180 seconds. When analyzing the effective stage of initiation reaction, a safety response threshold was introduced:

[0110] Lower limit of absorbance intensity α1= 0.05 A.U.

[0111] Upper limit of absorbance intensity α2= 1.20 A.U.

[0112] The time interval between the initial decrease and the stable decrease of C=O absorbance intensity is defined as the "effective curing interval" for the unified data analysis.

[0113] S3: Spectrum acquisition and data recording:

[0114] The infrared spectra of the two groups of samples were collected in the effective curing interval (15-105 seconds), and the data are shown in Table 1:

[0115] Table 1 Infrared spectra in the effective curing interval

[0116]

[0117] All spectral samples were measured at equal intervals, and the system was automatically calibrated for background.

[0118] S4: Variable rate calculation and quality determination:

[0119] With 15 seconds and 105 seconds as the ratio endpoints, the following calculations were made:

[0120] The rate of decrease of photoinitiator C=O absorption peak (ΔX) represents the consumption rate of the initiator;

[0121] The rate of increase of polymer product C–O–C absorption peak (ΔY) represents the generation rate of the product.

[0122] The calculations are as follows:

[0123] Group A:

[0124] ΔX = (1.00 - 0.10) / (105 - 15) = 0.01 A.U. / s;

[0125] ΔY = (0.91 - 0.20) / (105 - 15) ≈ 0.00789 A.U. / s;

[0126] Group B:

[0127] ΔX = (1.00 - 0.12) / 90 ≈ 0.00978 A.U. / s;

[0128] ΔY = (0.89 - 0.20) / 90 ≈ 0.00767 A.U. / s;

[0129] According to the above judgments:

[0130] The ΔX of Group A is slightly higher than that of Group B, indicating that the reaction rate is faster;

[0131] The ΔY of Group A is slightly higher than that of Group B, indicating that the product formation efficiency is slightly better.

[0132] Based on the determination rule set by the present application:

[0133] The ΔX of Group A does not exceed a significantly high value, and ΔY ≥ the ΔY of Group B;

[0134] Therefore, it is determined that the initiation efficiency meets the standard and the stability meets the standard (satisfying the T2 determination condition).

[0135] Conclusion: Based on the above data analysis, Irgacure® 819 exhibits high initiation activity and good stability under UV-A conditions, and is suitable for thick film or light shielding system photocuring scenarios. The detection method can effectively identify the reaction performance of the initiator under real conditions, and is suitable for application links such as photoinitiator research and development, screening, and incoming inspection.

[0136] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A method of detecting the quality of a photoinitiator, characterized in that, Comprising the following steps: S1, test preparation: prepare multiple test samples from the sample to be tested, divide the sample to be tested into a target sample group and a comparative sample group, and use inductive heating method to solidify the initiator to form a solidified film on the surface of the sample; wherein the target sample group uses the photoinitiator to be tested, and the comparative sample group uses one or more photoinitiators with known stable performance; S2, synchronous calibration of solidification state: using a time synchronization calibration method, the solidification degree of each sample solidified film is calibrated, so that each sample solidified film is in the "incomplete solidification stage" below the preset solidification degree target; The time synchronization calibration method specifically refers to: obtaining the spectral data of the photoinitiator by real-time infrared spectrum analysis method, the solidification stage is calibrated according to the real-time time axis, and the solidification time of the photoinitiator is taken as the horizontal coordinate, the material changes caused by the photoinitiator in the solidified film before and after solidification are analyzed, so as to calibrate the spectral response curve in the initiation reaction process, and determine the stage with positive reaction curve slope as the characteristic mark of the active initiation reaction stage; When the infrared spectrum is acquired for the first time, the spectrum data at this time is taken as a reference, and the corresponding time is defined as "0" point; after the initiator-cured film is completely cured, the last spectrum is acquired, and the time corresponding to this moment is defined as the curing time required ; the curing reaction curve of the initiator in the interval is a curve, and the corresponding curing time interval is referred to as the full curing interval; During the entire curing process, the material structure of the initiator and the coating material of the test sample changes, introducing test variables. The test variable Characterization parameters used to characterize the chemical reaction behavior of initiators during the curing process; test variables Test variables divided into initiators and initiator generation variables Satisfies the functional relationship: and ,in, For time; S3, synchronous acquisition of spectral data: under the calibrated "incomplete solidification stage", the infrared spectrum of the target sample group and the comparative sample group is tested, and the spectral data is continuously collected until the state of the sample solidified film reaches or exceeds the preset solidification degree target; S4, spectral data analysis: comparing the infrared spectral data of the target sample group and the comparative sample group under the same solidification stage, analyzing the dynamic reaction behavior of the photoinitiator to be tested in the target sample group in the solidification process, determining the initiation efficiency, and determining the quality of the initiator based on the initiation efficiency.

2. The method of claim 1, wherein: Test variables for initiator Generation variables for initiator is one of the following combinations: Q1, test variable Reference to spectral response intensity: denotes the intensity of the absorption peak of the initiator for a specific wavelength band, denotes the intensity of the absorption peak corresponding to the structure of the product during the curing process; Q2, test variable monomer conversion: indicates the degree of reactivity of the original monomer, indicates the degree of conversion of the generated polymer; Q3, test variable denotes the concentration of the photoinitiator: denotes the effective concentration of the photoinitiator, denotes the cumulative concentration of the reacted fraction.

3. The method of claim 2, wherein: The step S2 introduces a safety threshold The safety threshold is a range of absorption intensity variation obtained by infrared spectroscopy, used to represent the activity boundary of the photoinitiator in the process of curing reaction; wherein, represents the minimum effective response threshold, represents the highest acceptable response upper limit, and preset by spectrum comparison experiment of standard initiator; In the full curing interval, the initiation reaction curve has a common interval with the safety threshold which is the effective curing interval wherein the is the start time of the reaction initiated by the photoinitiator, is the end time of the reaction initiated by the photoinitiator .

4. The method of claim 3, wherein: In step S3, the initiation reaction curves of the target sample group and the control sample group are compared. With safety threshold public area Alignment is performed to ensure that the common intervals intersect the horizontal axis at the same point. The common intervals are determined by the leftmost and rightmost intersections with the horizontal axis. This makes the concentration curves of reactants and initiating membrane substances in the common common region comparable between the target sample group and the control sample group.

5. The method of claim 4, wherein: In the step S4, the determination of the initiation efficiency is specifically referring to determining the initiation efficiency of the initiator according to the change of the and .

6. The method of claim 5, wherein: In step S4, the change of the initial value of the test variable and is determined to determine the initiation efficiency of the initiator. Specifically, the change value of the test variable is calculated based on the initial value , and the formula is as follows. ​ ； ； wherein, and respectively represent a test variable of the initiator and a generation variable of the initiator from an initial time to a unit time change amount of time.

7. The method of claim 6, wherein: In step S4, determining the quality of the initiator based on the initiation efficiency specifically refers to: calculating the values of the target sample group and the comparison sample group and determining whether the initiation efficiency and stability of the target sample group meet the standards, the determination condition being that T1, if the value of the target sample group is higher than the value of the comparison sample group T1, if the value of the target sample group is higher than the value of the comparison sample group T1, if the value of the target sample group is higher than the value of the comparison sample group T2, if the value of the target sample group is equal to or lower than the value of the comparison sample group, and the value of the target sample group is equal to or higher than the value of the comparison sample group, the value of the target sample group is equal to or higher than the value of the comparison sample group, it is determined that the initiation efficiency of the target sample group meets the standard and the stability meets the standard;​​​ T3, if the value of the target sample group is equal to or lower than the value of the comparative sample group but the value of the target sample group is lower than the value of the comparative sample group but the value of the target sample group is lower than the value of the comparative sample group but the value of the target sample group is lower than the value of the comparative sample group but the value of the target sample group is lower than the value of the comparative sample group 8. The application of a method for detecting the quality of a photoinitiator according to any one of claims 1-7 in the quality detection of photoinitiator finished products.

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