A method for calculating process parameters of conjugated polymer microspheres

Abstract

The application discloses a kind of conjugated polymer microsphere process parameter calculation method, steps are as follows: the volume and interfacial tension of aqueous solution containing PVA and n-propanol are obtained, the volume and viscosity of conjugated polymer solution containing benign solvent, beaker diameter, stirring paddle diameter;Conjugated polymer droplet volume is set as third volume and conjugated polymer microsphere volume is fourth volume.By third volume, second volume, capillary length, tube diameter, viscosity, interfacial tension, static head and injection time, the injection thrust and frequency of micro-injection pump are calculated;Based on fourth volume, third volume, the volume of conjugated polymer solution, the volume of aqueous solution, viscosity, interfacial tension, beaker and stirring paddle diameter, and stirring time, the stirring speed is calculated.The conjugated polymer microsphere meeting the preset volume requirement is finally prepared according to the calculated result, the accurate control of microsphere volume is realized, and strong support is provided for stem cell dynamic tracing and other applications in biomedical field.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of polymer preparation, and particularly relates to a calculation method of process parameters of conjugated polymer microspheres. BACKGROUND

[0002] The conjugated polymer microspheres have excellent optical performance and biocompatibility, and can become a substitute for conventional fluorescent microspheres and can be applied to the biomedical field for dynamic tracking of stem cells in the future. At present, the research on the conjugated polymer microspheres is still in the exploratory stage in the laboratory.

[0003] In the laboratory, when the conjugated polymer microspheres are explored and verified for application, the conjugated polymer microspheres with a volume meeting the requirements are prepared according to the experimental scene, for example, when the conjugated polymer microspheres are used for tracking stem cells, the volume of the microspheres should match the phagocytosis capacity of the cells. If the volume of the microspheres is too large, the phagocytosis of the cells is hindered, and if the volume of the microspheres is too small, the microspheres are easily metabolized by the phagocytosis cells, resulting in failure of the tracking function.

[0004] The main process parameters affecting the volume of the conjugated polymer microspheres are injection thrust and stirring speed. When the injection thrust of the micro-injection pump is too large, the speed of the conjugated polymer droplets separated from the capillary is too fast, the accumulated time of the single droplet is shortened, and thus the volume of the formed conjugated polymer droplet is reduced. When the injection thrust is insufficient, the accumulated time of the droplet is too long, and thus the volume of the formed conjugated polymer droplet is increased. When the stirring speed is too large, the shear force is increased, the droplets are broken, and thus the volume of the conjugated polymer droplet is reduced. When the stirring is insufficient, the droplets are easily coalesced, and the evaporation efficiency of the benign solvent is reduced, resulting in coalescence of the droplets and too large volume of the microspheres.

[0005] Therefore, it is urgent to provide a calculation method of process parameters of conjugated polymer microspheres, so that the appropriate process parameters can be quickly and accurately determined according to different experimental requirements, and the conjugated polymer microspheres with a volume meeting the requirements can be prepared. SUMMARY

[0006] In order to at least overcome the above-mentioned deficiencies in the prior art, the purpose of the present application is to provide a calculation method of process parameters of conjugated polymer microspheres, which comprises the following steps:

[0007] obtaining the volume of the aqueous solution containing PVA and n-propanol as a first volume, and obtaining the interfacial tension of the aqueous solution;

[0008] obtaining the volume of the conjugated polymer solution containing a benign solvent as a second volume, and obtaining the viscosity of the conjugated polymer solution, wherein the benign solvent is chloroform;

[0009] obtaining the diameter of the beaker loaded with the aqueous solution, and obtaining the diameter of the stirring paddle at the bottom of the beaker;

[0010] taking the preset volume of the conjugated polymer droplet as a third volume, and taking the preset volume of the conjugated polymer microsphere as a fourth volume, the third volume being the volume of the conjugated polymer droplet injected into the aqueous solution from the capillary, and the fourth volume being the volume of the conjugated polymer microsphere after the chloroform is completely evaporated;

[0011] calculating the injection thrust of the micro-injection pump and the injection frequency according to the third volume, the second volume, the length of the capillary of the micro-injection pump, the diameter of the capillary of the micro-injection pump, the viscosity of the conjugated polymer solution, the interfacial tension, the static liquid height, and the preset injection time length, wherein the static liquid height is the preset height of the capillary nozzle to the liquid surface of the aqueous solution;

[0012] calculating the stirring speed of the stirring paddle according to the fourth volume, the third volume, the second volume, the first volume, the viscosity of the conjugated polymer solution, the interfacial tension, the diameter of the beaker, the diameter of the stirring paddle, and the preset stirring time length;

[0013] preparing the conjugated polymer microsphere according to the injection thrust, the injection frequency, and the stirring speed.

[0014] In the traditional preparation process of the conjugated polymer microsphere, the process parameters (including the injection thrust and the stirring speed) are mostly set according to human experience. This parameter setting method depending on subjective judgment often causes the size of the prepared conjugated polymer microsphere to be uncontrollable, the prepared conjugated polymer microspheres to have poor batch reproducibility and low yield, and the prepared conjugated polymer microspheres to be difficult to meet the precision requirements of biomedical applications, thereby seriously affecting the reliability and repeatability of the experimental results.

[0015] Therefore, the inventors of the present application provide a calculation method of process parameters of a conjugated polymer microsphere. The method obtains the physical parameters of the aqueous solution and the conjugated polymer solution, and establishes a complete process parameter calculation model in combination with a preset microsphere volume target. By accurately calculating the injection thrust and the injection frequency of the micro-injection pump and the stirring speed of the stirring paddle, the method realizes the rapid and accurate determination of suitable process parameters according to different experimental requirements, thereby preparing the conjugated polymer microspheres with a volume meeting the requirements, and provides strong support for the application of stem cell dynamic tracing in the biomedical field.

[0016] For the above-mentioned calculation method, the method first acquires key physical parameters of the aqueous solution containing PVA and n-propanol and the conjugated polymer solution containing a benign solvent, including the volume of the aqueous solution, the volume of the conjugated polymer solution, the interfacial tension, the viscosity of the conjugated polymer solution, and the like, and simultaneously acquires size parameters of the experimental equipment (beaker diameter, stirring paddle diameter, capillary tube length, capillary tube diameter, and static liquid height), to provide basic data for subsequent calculation.

[0017] Next, taking the preset conjugated polymer droplet volume as a target parameter, the key physical parameters of the aqueous solution and the conjugated polymer solution, the geometric parameters of the capillary tube (capillary tube length and capillary tube diameter), and the preset injection time are combined to calculate the injection thrust and injection frequency of the micro-injection pump.

[0018] Then, according to the preset conjugated polymer microsphere volume as a target parameter, the key physical parameters of the aqueous solution and the conjugated polymer solution, the preset conjugated polymer droplet volume, the size parameters of the experimental equipment, and the preset stirring time are combined to calculate the stirring speed of the stirring paddle.

[0019] Finally, the calculated injection thrust, injection frequency, and stirring speed are used as process parameters to prepare conjugated polymer microspheres that meet the volume size of the test scenario, so as to promote the accuracy of the conjugated polymer microsphere test research.

[0020] Further, the steps of calculating the injection thrust and injection frequency of the micro-injection pump are as follows:

[0021] The density of the conjugated polymer solution is acquired as a first density, and the density of the aqueous solution is acquired as a second density;

[0022] The total number of conjugated polymer droplets is calculated through the second volume and the third volume;

[0023] The injection frequency of the micro-injection pump is calculated according to the total number of conjugated polymer droplets and the preset injection time;

[0024] The conjugated polymer droplet flow rate is calculated according to the injection frequency and the third volume, and the flow pressure in the capillary tube is calculated according to the conjugated polymer droplet flow rate, the capillary tube length, the capillary tube diameter, and the viscosity of the conjugated polymer solution;

[0025] The critical pressure of the conjugated polymer droplet formation is calculated according to the interfacial tension and the third volume;

[0026] The liquid pressure on the conjugated polymer droplet is calculated according to the first density, the second density, and the static liquid height;

[0027] The injection thrust of the micro-injection pump is obtained by summing the flow pressure, the critical pressure, and the liquid pressure.

[0028] Further, the formula for calculating the total number of conjugated polymer droplets is:

[0029]

[0030] In the formula, N is the total number of conjugated polymer droplets, is the second volume, is the third volume.

[0031] Further, the formula for calculating the injection frequency of the micro-injection pump is:

[0032]

[0033] In the formula, f is the injection frequency, is the preset injection duration.

[0034] Further, the formula for calculating the flow pressure in the capillary is:

[0035]

[0036] In the formula, is the flow pressure in the capillary, d is the capillary inner diameter, L is the capillary length, is the viscosity of the conjugated polymer solution, is the flow rate of the conjugated polymer droplets.

[0037] Further, the formula for calculating the critical pressure for the formation of conjugated polymer droplets is:

[0038]

[0039] In the formula, is the critical pressure, σ is the interfacial tension, is the diameter of the conjugated polymer droplets.

[0040] Further, the formula for calculating the liquid pressure on the conjugated polymer droplets is:

[0041]

[0042] In the formula, is the liquid pressure, is the gravitational acceleration, h is the static liquid height, is the density difference, is the first density, is the second density.

[0043] Further, the step for calculating the stirring speed is:

[0044] The minimum dispersion efficiency required for the dispersion of conjugated polymer droplets is calculated based on interfacial tension, viscosity of the conjugated polymer solution, third volume, beaker diameter, and stirrer diameter.

[0045] The evaporation efficiency of the benign solvent in the solution is calculated based on the first volume, the second volume, the fourth volume, the preset stirring time, the beaker diameter, and the stirring paddle diameter.

[0046] The stirring speed of the impeller is calculated based on the minimum dispersion efficiency and evaporation efficiency.

[0047] Furthermore, the formula for calculating the stirring speed is as follows:

[0048]

[0049] In the formula, Let σ be the stirring speed, and σ be the interfacial tension. Let N be the viscosity of the conjugated polymer solution, and N be the total number of conjugated polymer droplets. The diameter of the conjugated polymer droplet is denoted as . For the fourth volume, To preset the stirring time, The diameter of the beaker is... The diameter of the agitator is [diameter]. Solution ratio correction factor.

[0050] In summary, the present invention has the following advantages compared with the prior art:

[0051] This invention discloses a method for calculating process parameters of conjugated polymer microspheres. It abandons the traditional method of relying on human experience to set process parameters, and through rigorous acquisition of physical parameters and a scientific calculation process, accurately determines key process parameters such as injection thrust, injection frequency, and stirring speed. This not only effectively avoids the problem of uncontrollable microsphere size caused by subjective judgment, but also ensures that the conjugated polymer microspheres prepared in each batch have good repeatability and a high yield rate. This allows them to precisely meet the stringent precision requirements of microspheres in biomedical applications, greatly improving the progress of experiments based on conjugated polymer microspheres, enhancing the reliability and reproducibility of experimental results, and powerfully promoting the research and application development of conjugated polymer microspheres in the biomedical field, especially in areas such as dynamic stem cell tracking. Attached Figure Description

[0052] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0053] Figure 1 This is a flowchart of the method for calculating the process parameters of the present invention;

[0054] Figure 2 Flow chart for calculating injection thrust and injection frequency of the present application;

[0055] Figure 3 Flow chart for calculating stirring speed of the present application;

[0056] Figure 4 Schematic diagram for injecting conjugated polymer solution into aqueous solution of the present application. DETAILED DESCRIPTION

[0057] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the embodiments and the accompanying drawings, the illustrative embodiments of the present application and the description thereof are only used to explain the present application, and are not regarded as a limitation to the present application.

[0058] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation to the present application.

[0059] In addition, the terms "first", "second" are only used for descriptive purpose, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features referred to. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0060] In the present application, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0061] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature can include that the first and second features are in direct contact, or can include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the first feature is "on", "above" and "over" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the first feature is horizontally higher than the second feature. The first feature is "under", "below" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the first feature is horizontally lower than the second feature.

[0062] In addition, the technical solutions among various embodiments can be combined with each other, but it must be based on that a person skilled in the art can realize, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist and is not within the scope of the present application.

[0063] In the subsequent description, suffixes such as "module", "component", "assembly" or "unit" are used only for the convenience of description of the present application, and have no specific meaning in itself. Therefore, they can be mixedly used.

[0064] The present application will be further described in detail through specific embodiments in combination with the accompanying drawings.

[0065] Please refer to Figure 1 and Figure 4 , a flow chart of a calculation method of process parameters of a conjugated polymer microsphere provided by an embodiment of the present application and a schematic diagram of injecting a conjugated polymer solution into an aqueous solution provided by an embodiment of the present application, further, the calculation method of the process parameters of the conjugated polymer microsphere can specifically include the contents described in the following steps.

[0066] Obtain the solution volume of the aqueous solution containing PVA and n-propanol as a first volume, and obtain the interfacial tension of the aqueous solution at the same time;

[0067] Obtain the volume of the conjugated polymer solution containing a benign solvent as a second volume, and obtain the viscosity of the conjugated polymer solution at the same time, wherein the benign solvent is chloroform;

[0068] Obtain the diameter of the beaker loaded with the aqueous solution, and obtain the diameter of the stirring paddle at the bottom of the beaker;

[0069] Take a preset conjugated polymer droplet volume as a third volume, and take a preset conjugated polymer microsphere volume as a fourth volume, the third volume is the volume of the conjugated polymer droplet injected into the aqueous solution from the capillary, and the fourth volume is the volume of the conjugated polymer microsphere after the chloroform is completely evaporated;

[0070] Based on the third volume, the second volume, the capillary length of the micro-injection pump, the capillary diameter of the micro-injection pump, the viscosity of the conjugated polymer solution, the interfacial tension, the static liquid height, and the preset injection time, the injection thrust and injection frequency of the micro-injection pump are calculated, wherein the static liquid height is the preset height from the capillary inlet to the surface of the aqueous solution.

[0071] The stirring speed of the stirring paddle is calculated based on the fourth volume, third volume, second volume, first volume, viscosity of the conjugated polymer solution, interfacial tension, beaker diameter, stirring paddle diameter, and preset stirring time.

[0072] Conjugated polymer microspheres were prepared based on the injection thrust, injection frequency, and stirring speed.

[0073] When this embodiment is implemented, as follows: Figure 4 As shown, the specific process for preparing conjugated polymer microspheres includes: injecting an aqueous solution containing PVA and n-propanol into a beaker; then placing the capillary of a micro-injection pump into the liquid surface of the beaker, and injecting the conjugated polymer solution containing a benign solvent into the beaker by applying injection thrust through the micro-injection pump. At this time, PVA and n-propanol, as a layer of surfactants, will encapsulate the conjugated polymer solution, forming conjugated polymer droplets; after injection, controlling the stirring speed of the stirrer to fully stir the liquid in the beaker until chloroform evaporates, forming conjugated polymer microspheres; then washing and collecting the conjugated polymer microspheres; next, placing the conjugated polymer microspheres in a flowing 95% N2 and 5% H2 mixed gas for overpressure annealing to form conjugated polymer microspheres that meet the experimental size and color gamut requirements.

[0074] However, in the above preparation process, the process parameters (including injection thrust and stirring speed) are usually set by human experience. This parameter setting method that relies on subjective judgment often results in uncontrollable size of the prepared conjugated polymer microspheres, poor batch-to-batch repeatability of the prepared conjugated polymer microspheres, and low yield. Consequently, the prepared conjugated polymer microspheres are difficult to meet the precision requirements of biomedical applications, which seriously affects the reliability and repeatability of experimental results.

[0075] Therefore, based on years of work experience, the inventor of the present application provides a conjugated polymer microsphere process parameter calculation method to obtain accurate injection thrust and stirring speed. Based on the two process parameters, conjugated polymer microspheres are prepared to achieve the size of the prepared microspheres meeting the specifications required by the experimental scene of its application, so as to ensure the reliability and repeatability of the test results. In the embodiment, the selected conjugated polymer solution includes poly[2-methoxy-5-(2-ethylhexyloxy)-p-phenylene] as a blue polymer solution, poly-((1E,1'E-(2,5-bis(2-ethylhexyloxy)-1,4-phenylene)bis(ethylene-2,1-diyl))bis(2,5-dimethoxybenzene)-4,4'-diyl) as a green polymer solution, and poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene] as a red polymer solution. The three are mixed with a good solvent in a specific ratio to form a conjugated polymer solution. In addition, 5% PVA (polyvinyl alcohol) and 0.5% n-propanol are mixed in water as an aqueous solution, then the conjugated polymer solution is sampled, and the viscosity of the sample (the viscosity of the conjugated polymer solution) is directly measured by a standard rheological experiment. The aqueous solution is sampled, and the interfacial tension of the aqueous solution is calculated by pendant drop method and Young-Laplace equation. In the embodiment, the third volume and the fourth volume are empirical values obtained by the inventor of the present application in a large number of preparation experiments for conjugated polymer microspheres. The third volume is in the range of 0.52fL ~ 65.45fL, and the fourth volume is in the range of 0.01fL ~ 1.31fL. In the embodiment, the good solvent is chloroform, the injection time is in the range of 1min ~ 2min, and the stirring time is 5h. The beaker diameter, stirring paddle diameter, capillary observation, capillary tube diameter and static liquid height required by the present application are obtained based on conventional measurement methods, which are not described here.

[0076] In the implementation of the embodiment, the injection thrust and the injection frequency of the micro-injection pump are calculated according to the third volume, the second volume, the capillary length of the micro-injection pump, the capillary diameter of the micro-injection pump, the viscosity of the conjugated polymer solution, the interfacial tension, the hydrostatic head and the preset injection time length; then, the stirring speed of the stirring paddle is calculated based on the fourth volume, the third volume, the second volume, the first volume, the viscosity of the conjugated polymer solution, the interfacial tension, the beaker diameter, the stirring paddle diameter and the preset stirring time length; finally, the conjugated polymer solution is injected into the beaker containing the aqueous solution by the micro-injection pump according to the calculated injection thrust and injection frequency; after the injection is completed, the liquid in the beaker is stirred by the stirring paddle according to the calculated stirring speed and the preset stirring time length until the chloroform is completely evaporated, thereby forming conjugated polymer microspheres of a size that meets the requirements of the test scenario, and then the washed conjugated polymer microspheres are subjected to overpressure annealing operation, thereby forming conjugated polymer microspheres of a specific color gamut; by using the accurately calculated process parameters and combining with subsequent preparation operations, the conjugated polymer microspheres of a size that meets the requirements can be stably and efficiently prepared according to the test requirements, and the experimental conditions and data quality are ensured; in the application in the medical field, the microspheres can better match the phagocytic capacity of cells, help to track the dynamics of stem cells, and effectively promote the application research of conjugated polymer microspheres in medical scientific research.

[0077] In a possible implementation, please refer to Figure 2 The step of calculating the injection thrust and the injection frequency of the micro-injection pump is as follows:

[0078] The density of the conjugated polymer solution is obtained as a first density, and the density of the aqueous solution is obtained as a second density;

[0079] The total number of conjugated polymer droplets is calculated based on the second volume and the third volume;

[0080] The injection frequency of the micro-injection pump is calculated based on the total number of conjugated polymer droplets and the preset injection time length;

[0081] The flow rate of the conjugated polymer droplets is calculated based on the injection frequency and the third volume, and the flow pressure in the capillary is calculated based on the flow rate of the conjugated polymer droplets, the capillary length, the capillary diameter and the viscosity of the conjugated polymer solution;

[0082] The critical pressure of the conjugated polymer droplets is calculated based on the interfacial tension and the third volume;

[0083] The liquid pressure on the conjugated polymer droplets is calculated based on the first density, the second density and the hydrostatic head;

[0084] The flow pressure, the critical pressure and the liquid pressure are summed to obtain an injection thrust of the microsyringe pump.

[0085] The principle of the embodiment is that the inventor of the application comprehensively considers fluid mechanics, interface physics and mass transfer and other factors in the preparation process of the conjugated polymer microspheres. In the droplet formation stage, the injection thrust needs to overcome the viscous resistance in the capillary, the surface tension when the droplet is formed and the liquid pressure generated by the static liquid height, so that the conjugated polymer solution can be dispersed into the aqueous solution in the form of stable droplets. Specifically, the flow pressure reflects the resistance characteristics of the polymer fluid flowing in the capillary, which is closely related to the solution viscosity, flow rate and capillary geometry; the critical pressure reflects the minimum pressure required to overcome the interfacial tension to form stable conjugated polymer droplets, which directly affects the size uniformity of the droplets; and the liquid pressure considers the influence of the depth of the capillary orifice on the formation of the droplets. Through accurate calculation and superposition of the three pressure components, the injection thrust for stable formation of droplets with a target volume can be obtained. At the same time, the injection frequency determined according to the total number of droplets and the injection time length can ensure that the quantitative conjugated polymer solution is uniformly dispersed within a predetermined time, providing good initial conditions for the formation of microspheres. This parameter calculation method based on multi-physical field coupling analysis breaks through the limitations of traditional empirical setting and lays a theoretical foundation for precise control of the size of conjugated polymer microspheres.

[0086] In one possible implementation, the formula for calculating the total number of conjugated polymer droplets is:

[0087]

[0088] In the formula, N is the total number of conjugated polymer droplets, is the second volume, is the third volume.

[0089] In one possible implementation, the formula for calculating the injection frequency of the microsyringe pump is:

[0090]

[0091] In the formula, f is the injection frequency, is the preset injection time length.

[0092] In one possible implementation, the formula for calculating the flow pressure in the capillary is:

[0093]

[0094] In the formula, is the flow pressure in the capillary, d is the capillary inner diameter, L is the capillary length, viscosity of the conjugated polymer solution, flow rate of the conjugated polymer droplet.

[0095] In a possible implementation, a formula for calculating the critical pressure of the conjugated polymer droplet formation is:

[0096]

[0097] wherein, Pc is the critical pressure, and σ is the interfacial tension, D is the diameter of the conjugated polymer droplet.

[0098] In a possible implementation, a formula for calculating the liquid pressure on the conjugated polymer droplet is:

[0099]

[0100] wherein, P is the liquid pressure, g is the acceleration of gravity, and h is the static liquid height, is the density difference, is the first density, is the second density.

[0101] In a possible implementation, referring to Figure 3 the step of calculating the stirring speed is:

[0102] according to the interfacial tension, the viscosity of the conjugated polymer solution, the third volume, the beaker diameter, and the stirring paddle diameter, to calculate a minimum dispersion efficiency required for the conjugated polymer droplet dispersion;

[0103] according to the first volume, the second volume, the fourth volume, the preset stirring duration, the beaker diameter, and the stirring paddle diameter, to calculate an evaporation efficiency of the good solvent in the solution;

[0104] according to the minimum dispersion efficiency and the evaporation efficiency, to calculate a stirring speed of the stirring paddle.

[0105] In the implementation of the present embodiment, the principle is that the inventors of the present application comprehensively consider the dispersion of conjugated polymer droplets, the evaporation of good solvent (chloroform) and the interaction of various substances in the system and other factors in the preparation process of conjugated polymer microspheres. In the stirring stage, the setting of the stirring speed needs to balance the dynamic balance of the dispersion effect of the conjugated polymer droplets and the evaporation efficiency of the good solvent. From the perspective of droplet dispersion, it is necessary to ensure that the shear force provided by stirring is sufficient to overcome the double action of interfacial tension and solution viscosity, so that the conjugated polymer droplets form a uniform and stable dispersion system in the aqueous solution. In this process, the size ratio of the beaker and the stirring paddle is the main factor directly affecting the hydrodynamic distribution (i.e. the dispersion rate of the conjugated polymer droplets). A larger beaker diameter with a suitable stirring paddle size can expand the range of shear force, while a too small stirring paddle diameter may lead to insufficient local vortex, affecting the uniformity of droplet breakage. The minimum dispersion efficiency determines the dispersion degree of the conjugated polymer droplets, which can avoid the coalescence of droplets due to insufficient dispersion, and further ensure that each droplet maintains an independent volume evolution path in the subsequent evaporation process. The minimum dispersion efficiency is closely related to the interfacial tension, the viscosity of the conjugated polymer solution, the droplet volume, the beaker diameter and the stirring paddle diameter. Only when a certain dispersion efficiency is reached, can the uniform distribution of droplets be ensured, and thus the evaporation efficiency of chloroform is ensured.

[0106] From the perspective of good solvent evaporation, the volatilization rate of chloroform is closely related to the mixing efficiency of the system. The stirring speed needs to promote sufficient gas-liquid interface renewal in unit time to accelerate the diffusion of chloroform from the inside of the conjugated polymer droplets to the aqueous phase and to the outside environment. This process involves parameters such as solution volume, microsphere volume, stirring time, container and stirring paddle size. When the volume of the conjugated polymer solution is significantly different from the total volume of the preset microspheres, it means that more chloroform needs to be evaporated, at which time the mass transfer efficiency needs to be enhanced by increasing the stirring speed. Therefore, the present application establishes a calculation relationship equation of stirring speed and dispersion efficiency, evaporation efficiency to ensure that under different experimental conditions, the optimal stirring speed can be determined through scientific calculation rather than empirical trial and error, thereby accurately controlling the size of the conjugated polymer microspheres, providing a guarantee for the repeatability of the experiment and the stability of the process.

[0107] In one possible implementation, the formula for calculating the stirring speed is:

[0108]

[0109] In the formula, is the stirring speed, σ is the interfacial tension, is the viscosity of the conjugated polymer solution, N is the total number of conjugated polymer droplets, is the diameter of the conjugated polymer droplets, is the fourth volume, is the preset stirring time, for beaker diameter, for stirrer diameter, solution ratio correction factor.

[0110] The above detailed description of the specific embodiments of the present application has further explained the purpose, technical solutions and beneficial effects of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for calculating the process parameters of conjugated polymer microspheres, characterized in that, It includes the following steps: Obtain the solution volume of the aqueous solution containing PVA and n-propanol as the first volume, and simultaneously obtain the interfacial tension of the aqueous solution; Obtain the volume of the conjugate polymer solution containing a good solvent as the second volume, and simultaneously obtain the viscosity of the conjugate polymer solution, where the good solvent is chloroform; Obtain the diameter of the beaker containing the aqueous solution, and obtain the diameter of the stirrer at the bottom of the beaker; Take the preset volume of the conjugate polymer droplets as the third volume, and take the preset volume of the conjugate polymer microspheres as the fourth volume. The third volume is the volume of the conjugate polymer droplets injected into the aqueous solution from the capillary, and the fourth volume is the volume of the conjugate polymer microspheres after complete evaporation of chloroform; Calculate the injection thrust and injection frequency of the micro-injection pump according to the third volume, the second volume, the capillary length of the micro-injection pump, the capillary diameter of the micro-injection pump, the viscosity of the conjugate polymer solution, the interfacial tension, the hydrostatic height, and the preset injection duration, where the hydrostatic height is the height from the preset capillary tube orifice to the liquid surface of the aqueous solution; Calculate the stirring speed of the stirrer according to the fourth volume, the third volume, the second volume, the first volume, the viscosity of the conjugate polymer solution, the interfacial tension, the beaker diameter, the stirrer diameter, and the preset stirring duration; Prepare conjugate polymer microspheres according to the injection thrust, injection frequency, and stirring speed; 2. The method for calculating process parameters of conjugated polymer microspheres according to claim 1, characterized in that, The steps for calculating the injection thrust and injection frequency of the micro-injection pump are: Obtain the density of the conjugate polymer solution as the first density, and simultaneously obtain the density of the aqueous solution as the second density; Calculate the total number of conjugate polymer droplets through the second volume and the third volume; Calculate the injection frequency of the micro-injection pump according to the total number of conjugate polymer droplets and the preset injection duration; Calculate the flow rate of the conjugate polymer droplets according to the injection frequency and the third volume, and calculate the flow pressure in the capillary according to the flow rate of the conjugate polymer droplets, the capillary length, the capillary diameter, and the viscosity of the conjugate polymer solution; Calculate the critical pressure for the formation of conjugate polymer droplets according to the interfacial tension and the third volume; Calculate the liquid pressure exerted on the conjugate polymer droplets according to the first density, the second density, and the hydrostatic height; Sum the flow pressure, the critical pressure, and the liquid pressure to obtain the injection thrust of the micro-injection pump; 3. The method for calculating process parameters of conjugated polymer microspheres according to claim 2, characterized in that, The formula for calculating the total number of conjugate polymer droplets is: In the formula, N is the total number of conjugated polymer droplets. For the second volume, This is the third volume.

4. The method for calculating process parameters of conjugated polymer microspheres according to claim 3, characterized in that, The formula for calculating the injection frequency of the micro-injection pump is: In the formula, f For injection frequency, Set the preset injection duration.

5. The method for calculating the process parameters of conjugated polymer microspheres according to claim 4, characterized in that, The formula for calculating the flow pressure in the capillary is: In the formula, Let d be the flow pressure inside the capillary, d be the inner diameter of the capillary, and L be the length of the capillary. The viscosity of the conjugated polymer solution. The flow rate of the conjugated polymer droplets is denoted as .

6. The method for calculating process parameters of conjugated polymer microspheres according to claim 5, characterized in that, The formula for calculating the critical pressure for the formation of conjugate polymer droplets is: In the formula, Where σ is the critical pressure and σ is the interfacial tension. The diameter of the conjugated polymer droplet is denoted as .

7. The calculation method of process parameters of a conjugated polymer microsphere according to claim 6, wherein The formula for calculating the liquid pressure exerted on the conjugate polymer droplets is: In the formula, For liquid pressure, Let h be the acceleration due to gravity and h be the height of the hydrostatic fluid. Due to density difference, For the first density, It is the second density.

8. The method for calculating process parameters of conjugated polymer microspheres according to claim 2, characterized in that, The steps for calculating the stirring speed are: Calculate the minimum dispersion efficiency required for the dispersion of conjugate polymer droplets according to the interfacial tension, the viscosity of the conjugate polymer solution, the third volume, the beaker diameter, and the stirrer diameter; Calculate the evaporation efficiency of the good solvent in the solution according to the first volume, the second volume, the fourth volume, the preset stirring duration, the beaker diameter, and the stirrer diameter; The stirring speed of the agitator is calculated based on the minimum dispersion efficiency and evaporation efficiency.

9. The method for calculating process parameters of conjugated polymer microspheres according to claim 8, characterized in that, The formula for calculating the stirring speed is: In the formula, Let σ be the stirring speed, and σ be the interfacial tension. Let N be the viscosity of the conjugated polymer solution, and N be the total number of conjugated polymer droplets. The diameter of the conjugated polymer droplet is denoted as . For the fourth volume, To preset the stirring time, The diameter of the beaker is... The diameter of the agitator is [diameter]. Solution ratio correction factor.

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