A method for improving stability of organic materials

Abstract

The application discloses a method for improving stability of organic materials, comprising the following steps: conducting trial production under the same feeding amount and the same temperature value, obtaining test data of relative content of stable solid and holding time by changing the holding time, and obtaining conversion time data of metastable solid converted into stable solid; obtaining a trend line formula between the relative content of stable solid and the conversion time and correcting the trend line formula; obtaining a mathematical model between the feeding amount and the conversion time required when the relative content of stable solid is 100% through the trend line formula and the trial production; obtaining the expected holding time or the maximum feeding amount in the mathematical model, and judging whether the production requirement is met; if the production requirement is not met, changing the temperature value and repeating the previous step to correct the mathematical model until the expected holding time or the maximum feeding amount meeting the production requirement is obtained. The application can effectively solve the dependence on the experience of process personnel in the process amplification.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and in particular to a method for improving the stability of organic materials. Background Technology

[0002] The performance of organic light-emitting diode (OLED) displays is highly dependent on the quality of organic small-molecule raw materials. The purity and stability of organic materials directly affect the lifespan of the light-emitting device during the manufacturing of the display or display device.

[0003] However, some organic electroluminescent small molecule materials possess the characteristics of organic molecules, such as the presence of chiral molecules in their molecular structure or unstable states such as metastable crystallization.

[0004] In existing technologies, the purification of organic electroluminescent materials generally employs organic solvent recrystallization and high-vacuum heating purification methods. Typically, molecular structures can be selected during the chemical synthesis stage; for example, selecting the left- or right-handed nature of intermediates yields a single left- or right-handed product, and selecting crystallization conditions yields a specific crystal form. However, performing such operations during the chemical synthesis stage generally requires operators with extensive knowledge, high-precision equipment, and significant plant construction costs.

[0005] In existing technologies, the purity of organic materials is generally characterized by methods such as high-performance liquid chromatography (HPLC) and differential scanning calorimetry (DSC). However, there is currently no universally applicable method to distinguish the stability differences of organic materials. Furthermore, metastable crystalline materials absorb some energy and become stable when continuously energized, which can affect the lifespan or yield of displays or display devices, resulting in defective products.

[0006] Furthermore, if it is necessary to convert the metastable crystallization of organic materials into the stable crystallization, the holding time needs to be controlled based on the experience of the process personnel. For process personnel who lack experience or whose experience is not applicable, it is difficult to grasp the holding time, thus making it difficult to solve the problem of the stability of organic materials. Summary of the Invention

[0007] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a method for improving the stability of organic materials.

[0008] The solution to the technical problem of this invention is:

[0009] A method for improving the stability of organic materials includes the following steps:

[0010] Trial production was carried out under the same feed amount and the same temperature value. By changing the holding time, experimental data on the relative content of stable solids and the holding time were obtained, and data on the conversion time of metastable solids to stable solids were obtained.

[0011] The trend line formula between the relative content of the stable solid and the conversion time was obtained and corrected.

[0012] Through the aforementioned trend line formula and trial production, a mathematical model was obtained regarding the relationship between the feed rate and the conversion time required when the relative content of the stable solids was 100%.

[0013] Based on the expected heat preservation time or maximum feed amount obtained from the mathematical model, determine whether it meets the production requirements. If it does not meet the production requirements, change the temperature value and repeat the previous step to revise the mathematical model until the expected heat preservation time or maximum feed amount that meets the production requirements is obtained.

[0014] The present invention has at least the following beneficial effects: By converting metastable crystalline materials into stable crystalline materials, the present invention simply and effectively solves the stability problem of organic light-emitting small molecule materials, thereby solving the problems of high technical requirements, high operational difficulty, and high equipment investment costs in the selection of stable states in chemical synthesis. Furthermore, by determining the method of process scale-up through small-batch pilot production, the present invention solves the problem of not being able to reasonably set process conditions during process scale-up, effectively reducing the dependence on the experience of process personnel during process scale-up. Even process personnel with insufficient or unsuitable experience can determine the parameters in actual production.

[0015] As a further improvement to the above technical solution, the step of conducting trial production under the same feed amount and temperature value, obtaining experimental data on the relative content of stable solids and the holding time by changing the holding time, and obtaining data on the conversion time of metastable solids to stable solids, includes the following steps:

[0016] Under the same feed amount and the same temperature value, the heat preservation time was changed, and the purification process was carried out under multiple heat preservation times;

[0017] The melting point of the materials in each collection area was tested by differential scanning calorimetry, and the relative content of stable solids was analyzed.

[0018] The sublimation purification time of the metastable solid was determined by the amount of material fed and the temperature value.

[0019] The conversion time was obtained based on the incubation time and the sublimation purification time.

[0020] Under the same feed amount and temperature, multiple sets of experiments were conducted using the controlled variable method to obtain experimental data on the relative content of stable solids and the holding time during the trial production. This allows us to obtain the conversion time from metastable solids to stable solids, which is beneficial for establishing mathematical models. Furthermore, the use of melting point testing to characterize and distinguish between metastable and stable solids reduces experimental costs.

[0021] As a further improvement to the above technical solution, the step of obtaining the conversion time based on the holding time and sublimation purification time includes the following steps:

[0022] Let the heat preservation time be t a The conversion time is t, and the sublimation purification time is t1;

[0023] Based on the formula relating incubation time, conversion time, and sublimation purification time: t a =t+t1, thus obtaining the conversion time.

[0024] The holding time can be obtained directly by timing, while the sublimation purification time can be obtained based on the amount of material fed and the temperature value, which can quickly determine the conversion time from metastable solid to stable solid.

[0025] As a further improvement to the above technical solution, the step of obtaining and correcting the trend line formula between the relative content of the stable solid and the conversion time includes the following steps:

[0026] The trend line formula between the relative content of stable solids and the conversion time is obtained based on the data of the relative content of stable solids and the conversion time.

[0027] The relative content of stable solids was 100% and substituted into the trend line formula. The conversion time obtained by the trend line formula was then verified with the actual heat preservation time.

[0028] The trend line formula was revised based on the verification results.

[0029] When the relative content of stable solids is 100%, the organic material is in a stable state. Using this data to verify the trend line formula can increase the reliability of the trend line formula, thereby obtaining the optimal solution.

[0030] As a further improvement to the above technical solution, the step of obtaining the trend line formula between the relative content of the stable solid and the conversion time based on the data of the relative content of the stable solid and the conversion time includes the following steps:

[0031] Let the feed amount be m, the relative content of stable solids be b, and the conversion time be t;

[0032] The actual BT diagram was obtained based on the data of the relative content of stable solids and conversion time.

[0033] Selecting a mathematical model

[0034] By using a computer to determine the constant c related to material properties and equipment characteristics, the mathematical model can be optimized. The generated BT plot matches the actual BT plot, and c is substituted into the mathematical model. From this, we obtain the trend line formula.

[0035] After selecting a suitable mathematical model, the experimental data from the pilot production can be substituted into the ideal mathematical model formula to solve for the values ​​of the parameters in the ideal mathematical model formula. This will yield the trend line formula of the relative content of the stable solid and the conversion time, which can guide the heat preservation time of the scale-up process. Based on the actual feed amount in production, the corresponding heat preservation time can be easily calculated.

[0036] As a further improvement to the above technical solution, the step of obtaining a mathematical model of the relationship between the feed rate and the conversion time required when the relative content of the stable solids is 100% through the trend line formula and trial production includes the following steps:

[0037] A mathematical model for the feed rate and conversion time is obtained using the trend line formula, and the corresponding MT chart is plotted.

[0038] By changing the feed rate, multiple sets of data on feed rate and conversion time are obtained, and an actual MT diagram is generated.

[0039] The mathematical model is revised based on the MT diagram of the mathematical model and the actual MT diagram.

[0040] By varying the amount of raw materials and using multiple sets of experimental data to increase the consistency between the ideal mathematical model and actual production, the accuracy of the data calculated by the mathematical model can be improved, thus ensuring that production can achieve higher economic benefits.

[0041] As a further improvement to the above technical solution, the step of obtaining the mathematical model of feeding amount and conversion time through the trend line formula, and plotting the corresponding MT chart of the mathematical model, includes the following steps:

[0042] Substitute b = 100% into the trend line formula. In this context, the mathematical model for obtaining the feed rate and the conversion time required when the relative content of the solids in the steady state is 100% is: m = log c (t+1);

[0043] The mt graph of the mathematical model is obtained by computer plotting.

[0044] When the relative content of stable solids is 100%, the organic material is in a relatively stable state. The heat preservation time obtained at this time is the optimal heat preservation time. The mathematical model obtained from this is a mathematical model that can improve the stability of organic materials. Production guidance based on this mathematical model can convert all metastable solids into stable solids, thereby achieving the greatest economic benefits.

[0045] As a further improvement to the above technical solution, the step of changing the feeding amount to obtain multiple sets of feeding amount and conversion time data, and then generating an actual MT diagram, includes the following steps:

[0046] By varying the amount of material fed, experimental data on the required heat preservation time for multiple sets of trial production with different amounts of material fed were obtained when the relative content of stable solids was 100%.

[0047] Based on the formula relating incubation time, conversion time, and sublimation purification time: t a = t + t1, which gives the conversion time required when the relative content of the stable solid is 100%;

[0048] Create an actual MT diagram based on the input production and conversion time.

[0049] By comparing the data obtained from the actual trial production with the data obtained from the mathematical model, the mathematical model can be further optimized to make it more consistent with actual production and further improve its accuracy.

[0050] As a further improvement to the above technical solution, the step of obtaining the expected heat preservation time or maximum feed amount from the mathematical model and determining whether it meets production requirements, and if it does not meet production requirements, changing the temperature value and repeating the previous step to correct the mathematical model until the expected heat preservation time or maximum feed amount that meets production requirements is obtained, includes the following steps:

[0051] By substituting the expected output amount of material or the longest heat preservation time that the process can accept into the mathematical model, the expected heat preservation time or maximum material input amount is obtained and compared with the actual situation.

[0052] If the production requirements are not met, the temperature value is changed, and the steps described above are repeated to obtain a mathematical model between the feed rate and the conversion time required when the relative content of the stable solids is 100% through the trend line formula and trial production.

[0053] If the production requirements are met, production will proceed based on the expected output amount of raw materials and the corresponding heat preservation time.

[0054] Mathematical models need to be based on actual production conditions. The data obtained by the mathematical model is compared with the actual production conditions to determine whether the data calculated by the mathematical model meets the production requirements. If the production requirements are met, the data calculated by the mathematical model is used to guide production. Otherwise, the mathematical model is modified so that the data calculated by the mathematical model meets the production requirements and achieves the maximum economic benefits.

[0055] As a further improvement to the above technical solution, the step of substituting the expected feed amount or the longest acceptable holding time into the mathematical model to obtain the expected holding time or maximum feed amount, and comparing it with the actual situation, includes the following steps:

[0056] Determine the expected feed volume m need The longest heat preservation time that the process can accept t amax ;

[0057] Based on the estimated feed volume m need Determine the required estimated conversion time t need and the expected insulation time t aneed ;

[0058] Through the longest heat preservation time t amax The maximum feed rate m under the current process conditions is obtained. max ;

[0059] If t aneed ≤t amax If it meets the production requirements, it is considered to meet the production requirements; otherwise, it is considered not to meet the production requirements.

[0060] If m need ≤m max If it meets the production requirements, it is considered to meet the production requirements; otherwise, it is considered not to meet the production requirements.

[0061] The mathematical model is validated by using the estimated feed amount and the longest acceptable heat preservation time under the current process conditions as criteria to determine whether the data calculated by the mathematical model meets the production requirements. Attached Figure Description

[0062] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly explained below. Obviously, the described drawings are only a part of the embodiments of the present invention, and not all of them. Those skilled in the art can obtain other design schemes and drawings based on these drawings without creative effort.

[0063] Figure 1 This is a flowchart of a method for improving the stability of organic materials according to an embodiment of the present invention;

[0064] Figure 2yes Figure 1 A detailed flowchart of step S100 in an embodiment;

[0065] Figure 3 yes Figure 1 A detailed flowchart of step S200 in an embodiment;

[0066] Figure 4 yes Figure 3 A detailed flowchart of step S210 in the embodiment;

[0067] Figure 5 yes Figure 1 A detailed flowchart of step S300 in an embodiment;

[0068] Figure 6 yes Figure 5 A detailed flowchart of step S310 in the embodiment;

[0069] Figure 7 yes Figure 5 A detailed flowchart of step S320 in the embodiment;

[0070] Figure 8 yes Figure 1 A detailed flowchart of step S400 in an embodiment;

[0071] Figure 9 This is a flowchart illustrating the method for improving the stability of organic materials according to an embodiment of the present invention.

[0072] Figure 10 This is a graph showing the relationship between the relative content of the stable solid and the conversion time obtained in the embodiments of the present invention;

[0073] Figure 11 This is a graph showing the relationship between the amount of material fed and the conversion time obtained in an embodiment of the present invention. Detailed Implementation

[0074] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0075] In the description of this invention, "several" means an indefinite quantity, "multiple" means two or more, "greater than", "less than", "exceeding" are understood to exclude the number itself, and "above", "below", "within" are understood to include the number itself.

[0076] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention. The various technical features of the present invention can be combined interactively without contradicting each other.

[0077] Since metastable crystalline materials absorb some energy and become stable when continuously energized, this can affect the lifespan or yield of displays or display devices, resulting in defective products. Therefore, during the purification process of organic materials, metastable crystals should be converted into stable crystals as much as possible to avoid the situation where metastable solids transform into stable solids during actual use.

[0078] Reference Figures 1 to 9 This invention proposes a method to improve the stability of organic materials. The method proposed in this invention enables organic materials to transform from metastable crystals to stable crystals during the purification process, avoiding the process of metastable crystals absorbing energy and becoming stable under continuous energization. This avoids the transformation process from affecting the lifespan of displays / display devices and reduces defective products.

[0079] It is understandable that in order to convert the metastable solid state of organic materials into a stable crystalline state, the holding time needs to be controlled based on the experience of the process personnel. The method proposed in this embodiment of the invention includes steps S100, S200, S300 and S400, which can solve the problem of determining the setting parameters for the current purification process scale-up. It effectively solves the dependence on the experience of process personnel during the process scale-up. Even process personnel with insufficient experience or whose experience is not applicable can determine the parameters in production based on the method in this embodiment of the invention, which is beneficial to guiding production and obtaining the greatest economic benefits.

[0080] Step S100: By changing the holding time, experimental data on the relative content of stable solids and the holding time are obtained, and data on the conversion time of metastable solids to stable solids are obtained.

[0081] Step S100 involves trial production of the organic material, which must be carried out under the same feed rate and temperature. It specifically includes steps S110, S120, S130, and S140, as described above. Figure 2 .

[0082] Step S110: Change the holding time and carry out the purification process under multiple sets of holding times.

[0083] Step S120: The melting point of the materials in each collection area is tested by differential scanning calorimetry, and the relative content of stable solids is analyzed.

[0084] Step S130: Determine the sublimation purification time of the metastable solid by controlling the amount of material fed and the temperature value.

[0085] Step S140: The conversion time is obtained based on the incubation time and the sublimation purification time.

[0086] Under the same feed amount and temperature, multiple sets of experiments were conducted using the controlled variable method to obtain experimental data on the relative content of stable solids and the holding time during the trial production, and the contents of Table 1 were supplemented.

[0087] Table 1. Relationship between heat preservation time and relative content of organic materials

[0088] n Feeding amount m <![CDATA[t1 value]]> t-value <![CDATA[t a Value <![CDATA[Melting point T d > Relative content (%) a, b 1 m <![CDATA[t1]]> 0 <![CDATA[t1]]> <![CDATA[T d1 ]]> <![CDATA[a1、b1(b1=0)]]> 2 m <![CDATA[t1]]> <![CDATA[t2]]> <![CDATA[t1+t2]]> <![CDATA[T d1 、T d2 ]]> <![CDATA[a2、b2]]> 3 m <![CDATA[t1]]> <![CDATA[t3]]> <![CDATA[t1+t3]]> <![CDATA[T d1 、T d2 ]]> <![CDATA[a3、b3]]> 4 m <![CDATA[t1]]> <![CDATA[t4]]> <![CDATA[t1+t4]]> <![CDATA[T d1 、T d2 ]]> <![CDATA[a4、b4]]> … …… …… …… …… …… …… n-1 m <![CDATA[t1]]> <![CDATA[t n-1 ]]> <![CDATA[t1+t n-1 ]]> <![CDATA[T d1 、T d2 ]]> <![CDATA[a n-1 、b n-1 (a n-1 ≠0) <!-- 5 -->]]> n m <![CDATA[t1]]> <![CDATA[t n ]]> <![CDATA[t1+t n ]]> <![CDATA[T d2 ]]> <![CDATA[a n 、b n (a n =0)]]>

[0089] Where n is the number of experimental data sets, m is the amount of feed, t1 is the sublimation purification time of the organic material, and t is the conversion time of the organic material from a metastable solid to a stable solid. a For the heat preservation time of organic materials, T d T is the melting point of organic materials. d1 T is the melting point of a metastable solid, while T d2 Let denoted as ρ be the melting point of the steady-state solid, and α be the relative content of the metastable solid. n Let be the relative content of the metastable solid in the nth group of experiments, and b be the relative content of the metastable solid. n The relative content of steady-state solids in the nth group of experiments, a n +b n =100%.

[0090] It is understandable that the incubation time, sublimation purification time, and conversion time have a related formula: t a =t+t1. During the experiment, the sublimation purification time can be obtained based on the amount of feed m and the temperature value during the trial production. The holding time can be directly obtained by timing. The conversion time can be calculated by the formula relating the holding time, sublimation purification time and conversion time.

[0091] It is understandable that the patent document CN114898825A, entitled "A Method for Determining Material Purification Process Using Mathematical Model", has proposed a method for determining the sublimation purification time by using the amount of feed and temperature. In this embodiment, the sublimation purification time of the corresponding amount of organic material can be obtained by using the method in the patent document.

[0092] It is understandable that a n and b nAs can be deduced from step S120, differential scanning calorimetry is a thermal analysis method and a commonly used characterization method in this field. Since the Gibbs free energies of the metastable and stable states are different, the melting points of solid materials will have slight differences. Therefore, in order to quickly characterize materials exhibiting metastable crystallization, this embodiment of the invention uses melting point testing to distinguish between metastable and stable crystallization, avoiding costly characterization methods such as X-ray diffraction.

[0093] It is understandable that the transformation from metastable crystal to stable crystal requires overcoming an energy barrier. In short, the transformation from metastable crystal to stable crystal requires the absorption of energy, and common energy sources include: light, radiation, pressure, and heating.

[0094] Considering the characteristics of high-vacuum heating purification methods for organic electroluminescent materials, which require continuous energy supply during the heating process, this embodiment of the invention uses this process to effectively convert metastable crystalline materials into stable crystalline materials without increasing equipment investment, raising operational requirements for personnel, or generating additional pollution, thereby improving the stability of organic materials.

[0095] Step S200 involves obtaining and correcting the trend line formula relating the relative content of the stable solid to the conversion time. Step 200 yields the relationship between b and t, expressed as a trend line formula, specifically including steps S210, S220, and S230. (Refer to...) Figure 3 .

[0096] Step S210: Based on the data of the relative content of the stable solid and the conversion time, obtain the trend line formula between the relative content of the stable solid and the conversion time.

[0097] In step S220, the relative content of the stable solid is 100% and is substituted into the trend line formula, and the conversion time obtained by the trend line formula is verified with the actual heat preservation time.

[0098] Step S230: Adjust the trend line formula based on the verification results.

[0099] It is understandable that when the relative content of stable solids is 100%, the organic material is in a stable state. Using this data to verify the trend line formula can increase the reliability of the trend line formula, thereby obtaining the optimal solution.

[0100] In this embodiment, step S210 includes steps S211, S212, and S213, as referred to Figure 4The trend line formula between the relative content of the stable solid and the conversion time is obtained through steps S211, S212 and S213.

[0101] Step S211: Obtain the actual BT diagram based on the data of the relative content of stable solids and conversion time.

[0102] Step S212, Select a mathematical model

[0103] Step S213: The constant c is calculated by computer to obtain the trend line formula.

[0104] It is understandable that the constant c is related to material properties and equipment characteristics, and can be obtained based on components with good product stability. The trend line formula corresponding to the BT plot is generated by computer, and needs to be fitted with the actual BT plot. In this embodiment, the obtained BT plot is referenced... Figure 10 .

[0105] Understandably, the data obtained through experiments can be used to create a scatter plot of BT (Block Transformation), and by connecting the scattered points in the scatter plot with a curve, the actual BT curve can be obtained.

[0106] Figure 10 The chart shows both the trendline curve derived from the mathematical model and the actual trendline curve. The trendline curve derived from the mathematical model is represented by a dashed line, while the actual trendline curve is represented by a solid line. Placing both the trendline curves on the same chart allows for a more intuitive view of their correlation, which is beneficial for refining the trendline formula.

[0107] Understandably, the trend line formula of the relative content of stable solids and conversion time is derived to guide the holding time of the scale-up process. Based on the actual amount of material fed in production, the corresponding holding time can be easily calculated.

[0108] Step S300 involves obtaining a mathematical model relating the feed rate to the conversion time required when the relative content of solids in the steady state is 100%, using a trend line formula and trial production. The specific steps include steps S310, S320, and S330, as described above. Figure 5 .

[0109] Step S310: Obtain the mathematical model of material input and conversion time through the trend line formula, and draw the corresponding mt graph of the mathematical model.

[0110] It is understandable that step S210 can yield a trend line formula relating the relative content of the stable solid to the conversion time. Step S310 obtains the mathematical model between the feed rate and the conversion time of b=100% using the trend line formula, specifically including steps S311 and S312, refer to... Figure 6 .

[0111] Step S311: Substitute b = 100% into the trend line formula. In this process, the mathematical model m = log0 is obtained. c (t+1).

[0112] Step S312: Obtain the mt diagram of the mathematical model by computer plotting.

[0113] It is understandable that the mathematical model obtained through step S311 is a model of the relationship between the amount of feed and the conversion time required for the relative content of stable solids to reach 100%, and the mt graph obtained through step S312 is a graph of the relationship between the amount of feed and the conversion time required for the relative content of stable solids to reach 100%. The data obtained through calculation can supplement Table 2 and make the data more intuitive.

[0114] Table 2. Relationship between m and t when the relative content of stable solids is 100%.

[0115]

[0116] Understandably, in Table 2, n represents the number of groups, and m... n This refers to the amount of material to be fed to the corresponding group. The sublimation purification time required for the corresponding number and amount of feed can be obtained according to the method provided in the patent document "A Method for Determining Material Purification Process Using a Mathematical Model". t is the conversion time required for the corresponding group feeding amount. a The value represents the required insulation time for the corresponding group's feed amount.

[0117] Step S320 involves changing the feed rate to obtain multiple sets of feed rate and conversion time data, and then plotting the actual mt graph. It is understood that step S310 is performed at the same temperature.

[0118] Reference Figure 7 Step S320 includes steps S321 and S322.

[0119] Step S321: Change the amount of feed to obtain experimental data on the conversion time required for multiple sets of feed trial production when the relative content of stable solids is 100%.

[0120] Understandably, the conversion time can be obtained from the formula relating the holding time, conversion time, and sublimation purification time. Using the method provided in the patent document "A Method for Determining Material Purification Process Using a Mathematical Model," the sublimation purification time corresponding to different feed amounts can be obtained.

[0121] Step S322: Create the actual mt diagram based on the input output and conversion time.

[0122] Based on data from multiple sets of feed rates obtained during trial production and the required holding time when the relative content of stable solids is 100%, the t-value was calculated, thus obtaining data for verifying the mathematical model. Based on the actual feed rate m... n The t-values ​​are used to generate a graph using a computer, resulting in the actual MT graph of the trial production.

[0123] Understandably, the conversion time data required for multiple sets of feed rates in trial production with a relative content of 100% in the stable state solid state, obtained through actual experiments, can also be listed in Table 2 to make the data more intuitive.

[0124] It is understandable that step S321 can be obtained from step S100. The conversion time required when the relative content of the stable solid obtained in S100 is 100% is the conversion time t required in step S321. By changing the feed amount m in step S100, the actual conversion time t corresponding to the relative content of the stable solid at 100% can be obtained under different feed amounts. It is understandable that the data obtained through experiments can be used to create a scatter plot. By using a computer to connect the scatter points in the scatter plot with a curve, the actual mt curve can be obtained.

[0125] Step S330: Based on the MT graph of the mathematical model and the actual MT graph, revise the mathematical model. Verify the mathematical model using actual data, and adjust the constant c in the mathematical model to ensure that the MT graph of the mathematical model matches the actual MT graph. In this embodiment, the obtained MT graph is referenced... Figure 11 .

[0126] Figure 11 The MT chart shown includes both the MT curve derived from the mathematical model and the actual MT curve. The MT curve derived from the mathematical model is represented by a dashed line, while the actual MT curve is represented by a solid line. Placing both the MT curve derived from the mathematical model and the actual MT curve on the same chart allows for a more intuitive view of their consistency, which is beneficial for refining the mathematical model.

[0127] It is understandable that step S310 or step S320 can be performed first. The data and mt graph obtained in step S320 are used to verify the data and mt graph derived from the mathematical model, and to further revise the mathematical model to obtain a mathematical model that is more consistent with the actual situation.

[0128] Understandably, changing the amount of raw materials and using multiple sets of experimental data to increase the consistency between the data obtained from the mathematical model and the actual production data is beneficial for optimizing the mathematical model, improving the accuracy of the data calculated by the mathematical model, and ensuring that production can achieve higher economic benefits.

[0129] In step S400, the expected heat preservation time or maximum feed amount is obtained from the mathematical model, and it is determined whether it meets the production requirements. If it does not meet the production requirements, the temperature value is changed and step S300 is repeated to correct the mathematical model until the expected heat preservation time or maximum feed amount that meets the production requirements is obtained.

[0130] Understandably, the obtained mathematical model needs to meet production requirements. If the data calculated by the obtained mathematical model does not meet the actual production requirements, then the mathematical model will not provide guidance for production. If the data calculated by the obtained mathematical model meets the actual production requirements, then production can be guided based on the data obtained from the mathematical model to achieve the greatest economic benefits.

[0131] Step S400 calculates the expected insulation time or maximum feed amount required for the expected feed amount, compares the calculated expected insulation time with the longest insulation time acceptable to the process, or compares the maximum feed amount with the expected feed amount.

[0132] Step S400 requires substituting the expected feed rate or the longest acceptable holding time into the mathematical model to derive the expected holding time or maximum feed rate, and then comparing it with the actual situation. This specifically includes steps S410, S420, S430, and S440, as described above. Figure 8 .

[0133] Step S410: Determine the expected feed amount m need The longest heat preservation time that the process can accept t amax .

[0134] Step S420, the expected feed amount m need Substituting into the mathematical model, the expected heat preservation time t is obtained. aneed It is understandable that the expected feed quantity m... need Substituting into the mathematical model, we can obtain the required estimated conversion time t. need The expected insulation time t can be obtained by analyzing the relationship between the conversion time and the insulation time.aneed .

[0135] Step S430, set the longest heat preservation time t amax Substituting the mathematical model into the equations and combining them with the model formulas provided in the patent document "A Method for Determining Material Purification Processes Using Mathematical Models," the maximum feed rate m under the current process conditions is obtained. max .

[0136] Step S440, if t aneed ≤t amax If m is considered to meet production requirements, then it is considered to not meet production requirements; otherwise, it is considered to not meet production requirements. need ≤m max If it meets the production requirements, it is considered to meet the production requirements; otherwise, it is considered not to meet the production requirements.

[0137] Understandably, if the maximum feed rate is greater than or equal to the expected feed rate, it indicates that at that temperature, the expected output of products can be produced by holding the product for the longest acceptable holding time, which is considered to meet production requirements; otherwise, it is considered that the expected output of products cannot be produced even by holding the product for the longest acceptable holding time, which is not considered to meet production requirements.

[0138] Understandably, if the expected insulation time required for the expected feed amount is less than or equal to the longest insulation time that the process can accept, it indicates that the current process conditions can complete the production of the expected feed amount and are considered to meet the production requirements; otherwise, it is considered that the current process conditions cannot complete the production of the expected feed amount and do not meet the production requirements.

[0139] Understandably, if the temperature does not meet production requirements, the temperature value needs to be changed and step S300 needs to be repeated; if the temperature meets production requirements, production can be scaled up using the expected feed amount and the corresponding expected holding time.

[0140] Understandably, if the production requirements are still not met after repeating step S300, then step S300 is repeated to correct the mathematical model until the production requirements are met, and then the process is scaled up for production.

[0141] Understandably, in subsequent process scale-up, the expected feed rate m will be used. need and the expected insulation time t aneed Producing goods will maximize economic benefits.

[0142] Understandably, the amount of material to be fed for the expected output is set based on production needs, while the maximum acceptable holding time for the process is set based on limitations such as production conditions and equipment.

[0143] In summary, this invention utilizes a method of heating and purifying under high vacuum to continuously provide energy, transforming metastable crystalline materials into stable crystalline materials. Since the purified organic material is in a stable state, the conversion from metastable to stable crystalline states will not occur during subsequent continuous power supply, thus avoiding the impact of the conversion process on the lifespan of the display or display device, reducing defective products, and simply and effectively solving the stability problem of organic light-emitting small molecule materials. This addresses the issues of high technical requirements, operational difficulty, and high equipment investment costs associated with selecting the stable state in chemical synthesis. Furthermore, this invention employs a method for determining process scale-up through small-batch pilot production. The resulting mathematical model can calculate reasonable and accurate holding times to guide production, solving the problem of inappropriate process condition settings during scale-up and effectively reducing reliance on the experience of process personnel. This facilitates maximizing economic benefits after process scale-up.

[0144] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A method for improving the stability of organic materials, characterized in that, Includes the following steps: Trial production was carried out under the same feed amount and the same temperature value. By changing the holding time, experimental data on the relative content of stable solids and the holding time were obtained, and data on the conversion time of metastable solids to stable solids were obtained. The process of obtaining and revising the trend line formula between the relative content of stable solids and conversion time includes the following steps: obtaining the trend line formula between the relative content of stable solids and conversion time based on the data of the relative content of stable solids and conversion time; substituting the relative content of stable solids as 100% into the trend line formula, and verifying the conversion time obtained by the trend line formula with the actual heat preservation time; and revising the trend line formula based on the verification results. The step of obtaining the trend line formula between the relative content of stable solids and the conversion time based on the data of the relative content of stable solids and the conversion time includes: setting the feed amount as... The relative content of stable solids is The conversion time is The actual results are obtained based on the data of the relative content of stable solids and conversion time. Figure; Selection of mathematical model Constants related to material properties and equipment characteristics are obtained through computer calculations. To make mathematical models Made Diagram and reality The image matches, and Substitute into the mathematical model From this, we obtain the trend line formula; A mathematical model was obtained using the trend line formula and trial production to determine the relationship between the feed rate and the conversion time required when the relative content of solids in the steady state is 100%. This process includes the following steps: obtaining the mathematical model of the feed rate and conversion time using the trend line formula, and plotting the corresponding mathematical model. Figure; By changing the feed rate, multiple sets of data on feed rate and conversion time are obtained, and practical results are made. Figure; based on the mathematical model Diagram and reality The figure shows the revised mathematical model; the mathematical model for obtaining the feed rate and conversion time through the trend line formula is described, and the corresponding mathematical model is plotted. The steps of the diagram include: Substitute into the trend line formula The mathematical model for obtaining the feed rate and the conversion time required when the relative content of the solids in the steady state is 100% is as follows: ; Mathematical models are obtained through computer-generated graphics. picture; Based on the expected heat preservation time or maximum feed amount obtained from the mathematical model, determine whether it meets the production requirements. If it does not meet the production requirements, change the temperature value and repeat the previous step to revise the mathematical model until the expected heat preservation time or maximum feed amount that meets the production requirements is obtained.

2. The method for improving the stability of organic materials according to claim 1, characterized in that, The steps of conducting trial production under the same feed amount and temperature, obtaining experimental data on the relative content of stable solids and the holding time by changing the holding time, and obtaining data on the conversion time of metastable solids to stable solids, include the following steps: Under the same feed amount and the same temperature value, the heat preservation time was changed, and the purification process was carried out under multiple heat preservation times; The melting point of the materials in each collection area was tested by differential scanning calorimetry, and the relative content of stable solids was analyzed. The sublimation purification time of the metastable solid was determined by the amount of material fed and the temperature value. The conversion time was obtained based on the incubation time and the sublimation purification time.

3. The method for improving the stability of organic materials according to claim 2, characterized in that, The step of obtaining the conversion time based on the incubation time and sublimation purification time includes the following steps: Keep warm for the following time: The conversion time is The sublimation purification time is ; Based on the formula relating incubation time, conversion time, and sublimation purification time: The conversion time is obtained.

4. The method for improving the stability of organic materials according to claim 1, characterized in that, The process involves changing the feed rate to obtain multiple sets of data on feed rate and conversion time, and then making actual adjustments. The steps involved in the diagram include the following: By varying the amount of material fed, experimental data on the required heat preservation time for multiple sets of trial production with different amounts of material fed were obtained when the relative content of stable solids was 100%. Based on the formula relating incubation time, conversion time, and sublimation purification time: The conversion time required when the relative content of the stable solid is 100% was obtained. Actual production capacity and conversion time should be determined based on the input output and conversion time. picture.

5. The method for improving the stability of organic materials according to claim 1, characterized in that, The step of obtaining the expected heat preservation time or maximum feed amount from the mathematical model, and determining whether it meets production requirements, and if not, changing the temperature value and repeating the previous step to correct the mathematical model until the expected heat preservation time or maximum feed amount that meets production requirements is obtained, includes the following steps: By substituting the expected output amount of material or the longest heat preservation time that the process can accept into the mathematical model, the expected heat preservation time or maximum material input amount is obtained and compared with the actual situation. If the production requirements are not met, the temperature value is changed, and the steps described above are repeated to obtain a mathematical model between the feed rate and the conversion time required when the relative content of the solids in the steady state is 100% through the trend line formula and trial production. If the production requirements are met, production will proceed based on the expected output amount of raw materials and the corresponding heat preservation time.

6. The method for improving the stability of organic materials according to claim 5, characterized in that, The step of substituting the expected feed rate or the longest acceptable holding time into the mathematical model to derive the expected holding time or maximum feed rate, and comparing it with the actual situation, includes the following steps: Determine the expected input quantity The longest heat preservation time that the process can accept. ; Based on the estimated input volume Determine the required estimated conversion time and expected insulation time ; Through the longest heat preservation time The maximum feed rate under the current process conditions is determined. ; like If it meets the production requirements, it is considered to meet the production requirements; otherwise, it is considered not to meet the production requirements. like If it meets the production requirements, it is considered to meet the production requirements; otherwise, it is considered not to meet the production requirements.

Images