Calculation method for process parameters of conjugated polymer microspheres

Abstract

The invention discloses a method for calculating process parameters of conjugated polymer microspheres. The method comprises the following steps: acquiring the volume and interfacial tension of a water phase solution containing PVA and n-propyl alcohol, the volume and viscosity of a conjugated polymer solution containing a benign solvent, the diameter of a beaker and the diameter of a stirring paddle; and setting the volume of the conjugated polymer liquid drops as a third volume and the volume of the conjugated polymer microspheres as a fourth volume. According to the third volume, the second volume, the capillary length, the pipe diameter, the viscosity, the interfacial tension, the hydrostatic height and the injection duration, the injection thrust and frequency of the micro-injection pump are calculated; and calculating the stirring speed based on the fourth volume, the third volume, the volume of the conjugated polymer solution, the volume of the aqueous phase solution, the viscosity, the interfacial tension, the diameters of the beaker and the stirring paddle and the stirring duration. Finally, the conjugated polymer microspheres meeting the preset volume requirement are prepared according to the result obtained through calculation, accurate control over the volume of the microspheres is achieved, and powerful support is provided for application such as stem cell dynamic tracing in the biomedicine field.

Description

Technical Field

[0001] The invention relates to the technical field of polymer preparation, in particular to a method for calculating process parameters of conjugated polymer microspheres. Background Art

[0002] Conjugated polymer microspheres have the potential to become a substitute for conventional fluorescent microspheres due to their excellent optical properties and biocompatibility. In the future, they may be used in the biomedical field for dynamic tracking of stem cells. Currently, most research on conjugated polymer microspheres is still in the laboratory exploration stage.

[0003] In the laboratory, when exploring and verifying the application of conjugated polymer microspheres, conjugated polymer microspheres with a volume that meets the requirements should be prepared according to the experimental scenario to which they are adapted. For example, when studying the tracing of stem cells by conjugated polymer microspheres, the volume of the microspheres must match the phagocytic ability of the cells. If the volume of the microspheres is too large, it will hinder the uptake of cells, while if the volume is too small, it will be easily metabolized by phagocytic cells, resulting in failure of the tracing function.

[0004] The main process parameters affecting the volume of conjugated polymer microspheres are injection thrust and stirring speed. When the injection thrust of the microinjection pump is too large, the conjugated polymer droplets will detach from the capillary too quickly, shortening the accumulation time of single droplets and reducing the volume of the formed conjugated polymer droplets. When the injection thrust is insufficient, the droplet accumulation time is too long, increasing the volume of the formed conjugated polymer droplets. When the stirring speed is too high, the shear force will be increased, promoting droplet breakage, and reducing the volume of the conjugated polymer droplets. When the stirring is insufficient, the droplets are prone to coalescence, and the evaporation efficiency of the benign solvent is reduced, resulting in droplet merging and excessive microsphere volume.

[0005] Therefore, there is an urgent need for a calculation method that can accurately calculate the process parameters of conjugated polymer microspheres, so as to quickly and accurately determine the appropriate process parameters according to different experimental requirements, thereby preparing conjugated polymer microspheres with a volume that meets the requirements. Summary of the Invention

[0006] In order to at least overcome the above-mentioned deficiencies in the prior art, the present application aims to provide a method for calculating the process parameters of conjugated polymer microspheres, the method comprising the following steps: Obtaining a volume of an aqueous solution containing PVA and n-propanol as a first volume, and simultaneously obtaining an interfacial tension of the aqueous solution; obtaining a volume of a conjugated polymer solution containing a benign solvent as a second volume, and simultaneously obtaining a viscosity of the conjugated polymer solution, wherein the benign solvent is chloroform; Obtain the diameter of the beaker containing the aqueous solution and the diameter of the stirring paddle at the bottom of the beaker; The preset conjugated polymer droplet volume is used as the third volume, and the preset conjugated polymer microsphere volume is used as the fourth volume. The third volume is the volume of the conjugated polymer droplet injected into the aqueous solution from the capillary tube, and the fourth volume is the volume of the conjugated polymer microsphere after the chloroform is completely evaporated. Calculating the injection thrust and injection frequency of the microinjection pump according to the third volume, the second volume, the capillary length and diameter of the microinjection pump, the viscosity of the conjugated polymer solution, the interfacial tension, the static liquid height, and the preset injection time, wherein the static liquid height is the height from the preset capillary orifice to the liquid surface of the aqueous solution; Calculate 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 beaker diameter, the stirring paddle diameter, and the preset stirring time; Conjugated polymer microspheres were prepared according to the injection thrust, injection frequency and stirring speed.

[0007] In the traditional preparation of conjugated polymer microspheres, process parameters (including injection thrust and stirring speed) are mostly set based on human experience. This parameter setting method that relies on subjective judgment often results in uncontrollable size of the prepared conjugated polymer microspheres, poor reproducibility between batches of the prepared conjugated polymer microspheres, and low yield. As a result, the prepared conjugated polymer microspheres are difficult to meet the precision requirements of biomedical applications, seriously affecting the reliability and repeatability of experimental results.

[0008] Based on this, the inventors of this application have provided a method for calculating the process parameters of conjugated polymer microspheres. This method establishes a comprehensive process parameter calculation model by acquiring the physical parameters of the aqueous solution and the conjugated polymer solution, combined with a preset microsphere volume target. By precisely calculating the injection thrust and injection frequency of the microinjection pump and the stirring speed of the stirring paddle, the method enables the rapid and accurate determination of appropriate process parameters based on different experimental requirements, thereby producing conjugated polymer microspheres of the required size. This method provides strong support for applications in the biomedical field, such as dynamic stem cell tracing.

[0009] Regarding the calculation method mentioned above, this method first obtains the 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, etc., and at the same time obtains the dimensional parameters of the experimental equipment (beaker diameter, stirring paddle diameter, capillary length, capillary diameter and static liquid height) to provide basic data for subsequent calculations.

[0010] Next, the preset conjugated polymer droplet volume is used as the target parameter, and the injection thrust and injection frequency of the microinjection pump are calculated based on the key physical parameters of the aqueous solution and the conjugated polymer solution, the geometric parameters of the capillary (capillary length and capillary diameter), and the preset injection time.

[0011] Then, based on the preset conjugated polymer microsphere volume as the target parameter, combined with 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, the stirring speed of the stirring paddle is calculated.

[0012] Finally, the calculated injection thrust, injection frequency, and stirring speed are used as process parameters to prepare conjugated polymer microspheres with a volume size that meets the test scenario, thereby promoting the accuracy of experimental research on conjugated polymer microspheres.

[0013] Furthermore, the steps for calculating the injection thrust and injection frequency of the microinjection pump are: Obtaining the density of the conjugated polymer solution as a first density, and simultaneously obtaining the density of the aqueous phase solution as a second density; The total number of conjugated polymer droplets is calculated using the second volume and the third volume; The injection frequency of the microinjection pump is calculated based on the total number of conjugated polymer droplets and the preset injection time; The conjugated polymer droplet flow rate is calculated according to the injection frequency and the third volume, and the flow pressure in the capillary is calculated according to the conjugated polymer droplet flow rate, the capillary length, the capillary diameter and the viscosity of the conjugated polymer solution; The critical pressure for the formation of conjugated polymer droplets was calculated based on interfacial tension and third volume. The liquid pressure on the conjugated polymer droplet is calculated according to the first density, the second density and the static liquid height; The injection thrust of the microinjection pump is obtained by summing the flow pressure, critical pressure and liquid pressure.

[0014] Furthermore, the formula for calculating the total number of conjugated polymer droplets is:

[0015] Where N is the total number of conjugated polymer droplets, is the second volume, The third volume.

[0016] Furthermore, the formula for calculating the injection frequency of the microinjection pump is:

[0017] Where f is the injection frequency, Set the injection duration.

[0018] Furthermore, the formula for calculating the flow pressure in the capillary is:

[0019] Where, is the flow pressure in the capillary, d is the inner diameter of the capillary, L is the length of the capillary, is the viscosity of the conjugated polymer solution, is the conjugated polymer droplet flow rate.

[0020] Furthermore, the formula for calculating the critical pressure of conjugated polymer droplet formation is:

[0021] Where, is the critical pressure, σ is the interfacial tension, is the diameter of the conjugated polymer droplet.

[0022] Furthermore, the formula for calculating the liquid pressure on the conjugated polymer droplet is:

[0023] Where, is the liquid pressure, is the acceleration due to gravity, h is the hydrostatic height, is the density difference, is the first density, It is the second density.

[0024] Further, the steps for calculating the stirring speed are: The minimum dispersion efficiency required for the dispersion of conjugated polymer droplets was calculated based on the interfacial tension, viscosity of the conjugated polymer solution, the third volume, beaker diameter, and stirring paddle diameter. Calculate the evaporation efficiency of the benign solvent in the solution based on the first volume, the second volume, the fourth volume, the preset stirring time, the beaker diameter, and the stirring paddle diameter; The stirring speed of the stirring paddle is calculated based on the minimum dispersion efficiency and evaporation efficiency.

[0025] Furthermore, the formula for calculating the stirring speed is:

[0026] Where, 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 droplet, is the fourth volume, To preset the stirring time, is the beaker diameter, is the diameter of the stirring paddle, Solution ratio correction factor.

[0027] In summary, the present invention has the following beneficial effects compared with the prior art: The present invention proposes a method for calculating the process parameters of conjugated polymer microspheres. This method abandons the traditional method of setting process parameters based on human experience. Instead, it accurately determines key process parameters such as injection thrust, injection frequency, and stirring speed through rigorous physical parameter acquisition and a scientific calculation process. This method not only effectively avoids the problem of uncontrollable microsphere size caused by subjective judgment, but also ensures that each batch of conjugated polymer microspheres prepared has good repeatability and a high yield rate, allowing them to accurately meet the strict requirements of microsphere precision in biomedical application scenarios. This method greatly improves the progress of experiments based on conjugated polymer microspheres, enhances the reliability and repeatability of experimental results, and strongly promotes the research and application development of conjugated polymer microspheres in the biomedical field, especially in the dynamic tracing of stem cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings: Figure 1 is a flow chart of a method for calculating process parameters of the present invention; Figure 2 A flow chart for calculating injection thrust and injection frequency according to the present invention; Figure 3 Flow chart of calculating stirring speed of the present invention; Figure 4 This is a schematic diagram of injecting a conjugated polymer solution into an aqueous solution according to the present invention. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0030] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0031] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0032] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0033] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0034] In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in this field can implement it. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of the present invention.

[0035] In the following description, suffixes such as “module,” “component,” “assembly,” or “unit” are used only to facilitate the description of the present invention and have no specific meanings. Therefore, they can be used interchangeably.

[0036] The present invention will be further described in detail below through specific embodiments with reference to the accompanying drawings.

[0037] Please refer to Figure 1 and Figure 4 , which is a flow chart of a method for calculating the process parameters of conjugated polymer microspheres provided in an embodiment of the present invention and a schematic diagram of injecting a conjugated polymer solution into an aqueous solution provided in an embodiment of the present invention. Furthermore, the method for calculating the process parameters of conjugated polymer microspheres can specifically include the contents described in the following steps.

[0038] Obtaining a volume of an aqueous solution containing PVA and n-propanol as a first volume, and simultaneously obtaining an interfacial tension of the aqueous solution; Obtaining a volume of a conjugated polymer solution containing a benign solvent as a second volume, and simultaneously obtaining a viscosity of the conjugated polymer solution, wherein the benign solvent is chloroform; Obtaining the diameter of the beaker containing the aqueous solution and the diameter of the stirring paddle at the bottom of the beaker; The preset conjugated polymer droplet volume is used as the third volume, and the preset conjugated polymer microsphere volume is used as the fourth volume, wherein the third volume is the volume of the conjugated polymer droplet injected into the aqueous solution from the capillary tube, and the fourth volume is the volume of the conjugated polymer microsphere after the chloroform is completely evaporated; Calculating the injection thrust and injection frequency of the microinjection pump according to the third volume, the second volume, the capillary length of the microinjection pump, the capillary diameter of the microinjection pump, the viscosity of the conjugated polymer solution, the interfacial tension, the static liquid height, and the preset injection time, wherein the static liquid height is the height from the preset capillary orifice to the liquid surface of the aqueous solution; Calculating a 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 beaker diameter, the stirring paddle diameter, and a preset stirring time; Conjugated polymer microspheres are prepared according to the injection thrust, injection frequency and stirring speed.

[0039] When this embodiment is implemented, Figure 4As shown, the process of preparing conjugated polymer microspheres specifically includes: injecting an aqueous solution containing PVA and n-propanol into a beaker; then placing the capillary nozzle of a microinjection pump into the liquid surface of the beaker, and applying an injection thrust through the microinjection pump to inject the conjugated polymer solution containing a benign solvent into the beaker. At this time, PVA and n-propanol will act as a layer of surfactant to wrap the conjugated polymer solution to form conjugated polymer droplets; after the injection is completed, the stirring paddle is controlled to apply a stirring speed to fully stir the liquid in the beaker until the chloroform evaporates to form conjugated polymer microspheres; then, the conjugated polymer microspheres are washed and collected; then, the conjugated polymer microspheres are placed in a flowing 95% N2 and 5% H2 mixed gas for overpressure annealing operation to form conjugated polymer microspheres that meet the experimental size and color gamut requirements.

[0040] However, in the above-mentioned preparation process, process parameters (including injection thrust and stirring speed) are usually set based on human experience. This parameter setting method that relies on subjective judgment often results in uncontrollable size of the prepared conjugated polymer microspheres, poor reproducibility between batches of the prepared conjugated polymer microspheres, and low yield. As a result, the prepared conjugated polymer microspheres are difficult to meet the precision requirements of biomedical applications, seriously affecting the reliability and repeatability of the experimental results.

[0041] Therefore, based on many years of professional experience, the inventors of this application provide a method for calculating the process parameters of conjugated polymer microspheres to obtain accurate injection thrust and stirring speed, and prepare conjugated polymer microspheres based on these two process parameters to achieve the specifications required by the experimental scenario of their application, so as to ensure the reliability and repeatability of the test results. In this 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-ethylene] is used as a red polymer solution, and 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 phase solution, and then the conjugated polymer solution is sampled, and the viscosity of the sample (viscosity of the conjugated polymer solution) is directly measured by a standard rheological experiment; the aqueous phase solution is sampled, and the interfacial tension of the aqueous phase solution is calculated by the hanging drop method and the Young-Laplace equation; in this embodiment, the third volume and the fourth volume are empirical values obtained based on a large number of preparation experiments conducted by the inventors of this application on conjugated polymer microspheres, wherein the value range of the third volume is 0.52fL ~65.45fL, the value range of the fourth volume is 0.01fL ~1.31fL; in this embodiment, the good solvent is chloroform, the injection time range is 1min ~2min, and the stirring time is 5h. The beaker diameter, stirring paddle diameter, capillary observation, capillary diameter and static liquid height required for this application are all obtained based on conventional measurement methods and will not be elaborated here.

[0042] When this embodiment is implemented, the injection thrust and injection frequency of the microinjection pump are calculated based on the third volume, the second volume, the capillary length of the microinjection pump, the capillary diameter of the microinjection pump, the viscosity of the conjugated polymer solution, the interfacial tension, the hydrostatic height and the preset injection time; 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; finally, the conjugated polymer solution is injected into the beaker containing the aqueous solution through the microinjection pump according to the calculated injection thrust and injection frequency; after the injection is completed, the stirring paddle is controlled to move at the calculated speed. The calculated stirring speed and preset stirring time are used to stir the liquid in the beaker until the chloroform is completely evaporated, thereby forming conjugated polymer microspheres of a size that meets the requirements of the experimental scenario. The washed conjugated polymer microspheres are then subjected to an overpressure annealing operation to form conjugated polymer microspheres of a specific color range. This embodiment uses precisely calculated process parameters combined with subsequent preparation operations to stably and efficiently prepare conjugated polymer microspheres of specifications that meet the requirements according to experimental needs, thereby ensuring experimental conditions and data quality. In medical applications, the microspheres can better match the cell phagocytic ability, help track stem cell dynamics, and effectively promote the application research of conjugated polymer microspheres in medical research.

[0043] In one possible implementation, please refer to Figure 2 , the steps for calculating the injection thrust and injection frequency of the microinjection pump are: Obtaining the density of the conjugated polymer solution as a first density, and simultaneously obtaining the density of the aqueous phase solution as a second density; Calculating the total number of conjugated polymer droplets using the second volume and the third volume; Calculating the injection frequency of the microinjection pump according to the total number of conjugated polymer droplets and a preset injection time; Calculating a conjugated polymer droplet flow rate according to the injection frequency and the third volume, and calculating a flow pressure in the capillary according to the conjugated polymer droplet flow rate, capillary length, capillary diameter, and viscosity of the conjugated polymer solution; Calculating the critical pressure for the formation of conjugated polymer droplets based on the interfacial tension and the third volume; Calculating the liquid pressure on the conjugated polymer droplet according to the first density, the second density and the static liquid height; The flow pressure, critical pressure and liquid pressure are summed to obtain the injection thrust of the microinjection pump.

[0044] The principle behind this embodiment is that the inventors comprehensively considered multiple factors during the preparation of conjugated polymer microspheres, including fluid mechanics, interfacial physics, and mass transfer. During the droplet formation stage, the injection thrust must overcome the viscous resistance within the capillary, the surface tension during droplet formation, and the liquid pressure generated by the hydrostatic height to disperse the conjugated polymer solution 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 and is closely related to the solution viscosity, flow rate, and capillary geometry. The critical pressure represents the minimum pressure required to overcome interfacial tension to form stable conjugated polymer droplets, directly affecting the size uniformity of the droplets. The liquid pressure considers the influence of the depth of the capillary orifice on droplet formation. By accurately calculating and superimposing these three pressure components, the injection thrust that ensures the stable formation of droplets at the target volume can be determined. Furthermore, the injection frequency, determined based on the total number of droplets and the injection duration, ensures that a fixed amount of conjugated polymer solution is evenly dispersed within a preset time, providing excellent initial conditions for subsequent microsphere formation. This parameter calculation method based on multi-physics field coupling analysis breaks through the limitations of traditional empirical settings and lays a theoretical foundation for achieving precise control of the size of conjugated polymer microspheres.

[0045] In one possible implementation, the formula for calculating the total number of conjugated polymer droplets is:

[0046] Where N is the total number of conjugated polymer droplets, is the second volume, The third volume.

[0047] In one possible implementation, the formula for calculating the injection frequency of the microinjection pump is:

[0048] Where, f is the injection frequency, Set the injection duration.

[0049] In one possible implementation, the formula for calculating the flow pressure in the capillary is:

[0050] Where, is the flow pressure in the capillary, d is the inner diameter of the capillary, L is the length of the capillary, is the viscosity of the conjugated polymer solution, is the conjugated polymer droplet flow rate.

[0051] In one possible implementation, the formula for calculating the critical pressure for the formation of conjugated polymer droplets is:

[0052] Where, is the critical pressure, σ is the interfacial tension, is the diameter of the conjugated polymer droplet.

[0053] In one possible implementation, the formula for calculating the liquid pressure on the conjugated polymer droplet is:

[0054] Where, is the liquid pressure, is the acceleration due to gravity, h is the hydrostatic height, is the density difference, is the first density, It is the second density.

[0055] In one possible implementation, please refer to Figure 3 , the steps to calculate the stirring speed are: Calculating the minimum dispersion efficiency required for dispersion of the conjugated polymer droplets based on the interfacial tension, the viscosity of the conjugated polymer solution, the third volume, the beaker diameter, and the stirring paddle diameter; Calculating the evaporation efficiency of the benign solvent in the solution based on the first volume, the second volume, the fourth volume, the preset stirring time, the beaker diameter, and the stirring paddle diameter; The stirring speed of the stirring paddle is calculated based on the minimum dispersion efficiency and evaporation efficiency.

[0056] In the implementation of this embodiment, the principle is that the inventors of this application comprehensively considered multiple factors such as the dispersion of conjugated polymer droplets, the evaporation of the good solvent (chloroform), and the interaction between various substances in the system during the preparation of conjugated polymer microspheres. During the stirring stage, the setting of the stirring speed needs to take into account the dynamic balance between 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 the stirring is sufficient to overcome the dual effects 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 fluid dynamics distribution (i.e., the dispersion rate of the conjugated polymer droplets). A larger beaker diameter with an appropriate stirring paddle size can expand the range of the shear force, while a stirring paddle diameter that is too small may lead to insufficient local eddy currents, affecting the uniformity of droplet breakup. The minimum dispersion efficiency determines the degree of dispersion of the conjugated polymer droplets, which can prevent the droplets from coalescing due to insufficient dispersion, thereby ensuring that each droplet maintains an independent volume evolution path during 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 by achieving a certain dispersion efficiency can the uniform distribution of the droplets be guaranteed, thereby ensuring the evaporation effect of chloroform.

[0057] 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 per unit time to accelerate the diffusion of chloroform from the inside of the conjugated polymer droplets to the aqueous phase and its volatilization to the external 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 preset total volume of the microspheres, it means that more chloroform needs to be evaporated. At this time, the mass transfer efficiency needs to be enhanced by increasing the stirring speed. Therefore, this application establishes a calculation relationship equation between the stirring speed and the dispersion efficiency and evaporation efficiency to ensure that under different experimental conditions, the optimal stirring speed can be determined by scientific calculation rather than empirical trial and error, thereby accurately controlling the size of the conjugated polymer microspheres and providing guarantees for the repeatability of the experiment and the stability of the process.

[0058] In one possible implementation, the formula for calculating the stirring speed is:

[0059] Where, 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 droplet, is the fourth volume, To preset the stirring time, is the beaker diameter, is the diameter of the stirring paddle, Solution ratio correction factor.

[0060] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for calculating process parameters of conjugated polymer microspheres, characterized in that: The following steps are involved: Obtaining a volume of an aqueous solution containing PVA and n-propanol as a first volume, and simultaneously obtaining an interfacial tension of the aqueous solution; Obtaining a volume of a conjugated polymer solution containing a benign solvent as a second volume, and simultaneously obtaining a viscosity of the conjugated polymer solution, wherein the benign solvent is chloroform; Obtaining the diameter of the beaker containing the aqueous solution and the diameter of the stirring paddle at the bottom of the beaker; The preset conjugated polymer droplet volume is used as the third volume, and the preset conjugated polymer microsphere volume is used as the fourth volume, wherein the third volume is the volume of the conjugated polymer droplet injected into the aqueous solution from the capillary tube, and the fourth volume is the volume of the conjugated polymer microsphere after the chloroform is completely evaporated; Calculating the injection thrust and injection frequency of the microinjection pump according to the third volume, the second volume, the capillary length of the microinjection pump, the capillary diameter of the microinjection pump, the viscosity of the conjugated polymer solution, the interfacial tension, the static liquid height, and the preset injection time, wherein the static liquid height is the height from the preset capillary orifice to the liquid surface of the aqueous solution; Calculating a 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 beaker diameter, the stirring paddle diameter, and a preset stirring time; Conjugated polymer microspheres are prepared 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, wherein: The steps for calculating the injection thrust and injection frequency of the microinjection pump are: Obtaining the density of the conjugated polymer solution as a first density, and simultaneously obtaining the density of the aqueous phase solution as a second density; Calculating the total number of conjugated polymer droplets using the second volume and the third volume; Calculating the injection frequency of the microinjection pump according to the total number of conjugated polymer droplets and a preset injection time; Calculating a conjugated polymer droplet flow rate according to the injection frequency and the third volume, and calculating a flow pressure in the capillary according to the conjugated polymer droplet flow rate, capillary length, capillary diameter, and viscosity of the conjugated polymer solution; Calculating the critical pressure for the formation of conjugated polymer droplets based on the interfacial tension and the third volume; Calculating the liquid pressure on the conjugated polymer droplet according to the first density, the second density and the static liquid height; The flow pressure, critical pressure and liquid pressure are summed to obtain the injection thrust of the microinjection pump.

3. The method for calculating process parameters of conjugated polymer microspheres according to claim 2, wherein: The formula for calculating the total number of conjugated polymer droplets is: Where N is the total number of conjugated polymer droplets, is the second volume, The third volume.

4. The method for calculating process parameters of conjugated polymer microspheres according to claim 3, wherein: The formula for calculating the injection frequency of the microinjection pump is: Where, f is the injection frequency, Set the injection duration.

5. The method for calculating process parameters of conjugated polymer microspheres according to claim 4, wherein: The formula for calculating the flow pressure in the capillary is: Where, is the flow pressure in the capillary, d is the inner diameter of the capillary, L is the length of the capillary, is the viscosity of the conjugated polymer solution, is the conjugated polymer droplet flow rate.

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 of conjugated polymer droplet formation is: Where, is the critical pressure, σ is the interfacial tension, is the diameter of the conjugated polymer droplet.

7. The method for calculating process parameters of conjugated polymer microspheres according to claim 6, characterized in that: The formula for calculating the liquid pressure on the conjugated polymer droplet is: Where, is the liquid pressure, is the acceleration due to gravity, h is the hydrostatic height, is the density difference, is the first density, It is the second density.

8. The method for calculating process parameters of conjugated polymer microspheres according to claim 2, wherein: The steps to calculate the stirring speed are: Calculating the minimum dispersion efficiency required for dispersion of the conjugated polymer droplets based on the interfacial tension, the viscosity of the conjugated polymer solution, the third volume, the beaker diameter, and the stirring paddle diameter; Calculating the evaporation efficiency of the benign solvent in the solution based on the first volume, the second volume, the fourth volume, the preset stirring time, the beaker diameter, and the stirring paddle diameter; The stirring speed of the stirring paddle 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: Where, 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 droplet, is the fourth volume, To preset the stirring time, is the beaker diameter, is the diameter of the stirring paddle, Solution ratio correction factor.

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