Preparation method of heteromorphic polymer microparticles
Through the coordinated regulation of droplet microfluidic control technology and solvent volatility, the problem of morphology control of non-spherical microparticles is solved, and the preparation of multi-morphic microparticles is realized. It is suitable for a variety of polymer systems and meets the diversified needs of biomedical and catalytic fields.
Patent Information
- Application Number
- CN202510865199.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-25
- Publication Date
- 2025-08-15
AI Technical Summary
It is difficult for the prior art to accurately regulate the morphological structure of non-spherical microparticles to meet the needs of diverse applications. Traditional methods have problems such as poor morphological controllability, uneven particle size or complex process.
The droplet microfluidic control technology and the coordinated control strategy of solvent volatility are used to regulate the concentration of polymer components, polyvinyl alcohol aqueous solution and constant temperature to generate distinctive polymer microparticles.
It realizes controllable preparation of multi-morphological microparticles from spherical to dumbbell-shaped, with universality and high repeatability, is suitable for a variety of polymer systems, and expands the application range of functional microparticles.
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Figure CN120484326A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of polymer microparticle preparation, in particular to a method for preparing special-shaped polymer microparticles. Background Art
[0002] Due to their unique physicochemical properties, such as structural asymmetry, differentiated component distribution, and surface characteristics, non-spherical polymer particles have shown broad application potential in optical devices, biomedicine, catalysis, and other fields. Particle shape is a key parameter that can significantly affect particle function. For example, the amphiphilicity of dumbbell-shaped particles can enhance interfacial adsorption capacity, while porous or multi-protrusion rough structures can improve loading efficiency or surface reactivity. Currently, how to precisely control the morphology and structure of non-spherical microparticles to adapt to diverse application needs has become a research hotspot in the field of materials preparation.
[0003] Traditional preparation methods such as electrospraying, mechanical stretching or micromolding have problems such as poor morphology controllability, non-uniform particle size or complex process. In contrast, droplet microfluidics technology has become an ideal platform for preparing microparticles with complex morphologies due to its high throughput, monodispersity and precise fluid manipulation capabilities. At present, researchers have successfully prepared core-shell, hollow or asymmetric particles through interfacial polymerization, photocuring or solvent evaporation, but existing methods are often limited by material compatibility or morphological uniformity. Therefore, the development of universal strategies to expand the diversity of material systems and morphologies remains a challenge that needs to be overcome. Summary of the Invention
[0004] To address the shortcomings of the prior art, the present invention provides a method for preparing heterogeneous polymer microparticles. By utilizing droplet microfluidics and a synergistic control strategy for solvent evaporation, the method enables the controlled preparation of microparticles in various shapes, ranging from spheres and dumbbells to raspberries. This method boasts universal applicability, high reproducibility, and a simple process. It is adaptable to a variety of polymer systems and meets the diverse demands for complex microparticles in fields such as biomedicine, catalysis, and functional materials.
[0005] To achieve the above object, the present invention adopts the following technical solutions:
[0006] The present invention provides a method for preparing heteromorphic polymer microparticles, comprising:
[0007] A polymer solution is used as the inner oil phase and a polyvinyl alcohol aqueous solution is used as the outer water phase. Microdroplets are generated using a droplet microfluidic chip and placed under constant temperature conditions to evaporate the solvent. By regulating the composition and proportion of the polymer, the concentration of the polyvinyl alcohol aqueous solution and the constant temperature, the microdroplets are induced to undergo controllable phase separation or interfacial self-assembly, and finally solidify into heteromorphic polymer microparticles.
[0008] Preferably, the polymer is selected from any one or more of poly(lactic-co-glycolic acid) (PLGA), poly(vinyl acetate) (PVAc), poly(methyl methacrylate) (PMMA), and polystyrene (PS).
[0009] In some embodiments of the present invention, the polymer may be any one or more of a single-component polymer, a two-component polymer, a three-component polymer, and a four-component polymer. When the polymer is a two-component polymer, the concentration ratio between the two components is any one of 1:0.5, 0.5:0.5, 0.5:1, or a value between the two. When the polymer is a three-component polymer, the concentration ratio between the three components is any one of 0.5:0.5:0.25, 0.5:0.5:0.5, 0.5:0.5:1.0, or a value between the two. When the polymer is a four-component polymer, the concentration ratio between the four components is any one of 0.5:0.5:0.5:0.1, 0.5:0.5:0.5:0.3, 0.5:0.5:0.5:0.5, or a value between the two.
[0010] It should be noted that the polymer system can be expanded to other polymers that are soluble in chloroform and have similar solubility characteristics, including homopolymers, random copolymers, and block copolymers. The present invention regulates the morphology of heterogeneous polymer microparticles by controlling the components and ratios of the polymers, such as the selective formation of surface pits, internal porosity, dumbbell-shaped structures, raspberry-like porous structures, snowman-shaped structures, porous spherical structures, porous dumbbell-shaped structures, spindle-shaped structures, bi-spherical structures, typical Janus structures, popcorn-shaped structures, trihedral structures, and spherical-like structures.
[0011] Preferably, the solvent in the inner oil phase is selected from chloroform or an organic solvent having similar physical and chemical properties to chloroform.
[0012] Preferably, the concentration of the solution containing the polymer is 0.5% to 1.0% w / v.
[0013] Preferably, the concentration of the polyvinyl alcohol aqueous solution is 0.5% to 5.0% w / v. Exemplarily, the concentration of the polyvinyl alcohol aqueous solution is any one of 0.5% w / v, 2.0% w / v, and 5.0% w / v, or a value in between. By adjusting the concentration of the polyvinyl alcohol aqueous solution, the surface and internal pores of the heteromorphic polymer microparticles can be controlled.
[0014] Preferably, the polyvinyl alcohol has a degree of alcoholysis of 87-89% and a molecular weight of 13,000-23,000.
[0015] Preferably, the process of generating microdroplets using a droplet microfluidic chip is: injecting the inner oil phase into the organic phase microchannel of the droplet microfluidic chip, and injecting the outer aqueous phase into the aqueous phase microchannel of the droplet microfluidic chip, and obtaining microdroplets of the same particle size by adjusting the flow rates of the inner oil phase and the outer aqueous phase.
[0016] More preferably, the flow rate of the inner oil phase is 400 μL / h, and the flow rate of the outer water phase is 1200 μL / h.
[0017] More preferably, the particle size of the microdroplets is 145 μm.
[0018] Preferably, the microdroplets are monodisperse oil-in-water (O / W) microdroplets.
[0019] Preferably, the constant temperature condition is 5° C. to 30° C. Exemplarily, the constant temperature condition is any one of 5° C., 20° C., 30° C., or a value in between. By regulating the temperature, the surface pores of the heteromorphic polymer microparticles can be adjusted.
[0020] Preferably, the morphology of the heteromorphic polymer microparticles is selected from any one or more of surface pits, internal porosity, dumbbell-shaped structure, raspberry-shaped porous structure, snowman-shaped structure, porous spherical structure, porous dumbbell-shaped structure, spindle-shaped structure, double spherical structure, typical Janus structure, popcorn-shaped structure, trihedral structure, and spherical-like structure.
[0021] The beneficial effects of the present invention are:
[0022] The present invention proposes a method for preparing heteromorphic polymer microparticles. Based on the method of coordinated control of droplet microfluidics and solvent volatilization, by designing parameters such as the component ratio of the polymer in the inner oil phase, the concentration of the polyvinyl alcohol aqueous solution in the outer water phase, and the temperature conditions, the controllable preparation of multi-morphological microparticles ranging from spherical, dumbbell-shaped to raspberry-shaped is achieved (such as Figure 1 The material of the present invention has universal applicability and is applicable to various polymers such as PLGA, PS, PMMA, PVAc and their composite systems, thus expanding the application range of functionalized microparticles.
[0023] The controllable process of this invention, based on the coordinated regulation of monodisperse droplet formation and solvent evaporation through microfluidics, enables large-scale production of uniform particle size and highly reproducible morphology. This technology not only overcomes the limitations of traditional methods in morphology control and material compatibility, but also opens up new avenues for the precise design and preparation of functionalized microparticles. It has important application value in areas such as drug delivery and functional coatings, and provides new research perspectives and methodological support for basic polymer theory research. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1A brief overview of the preparation of polymer microparticles with different shapes by regulating design parameters;
[0025] Figure 2 Diagram of the mechanism for controlling the morphology of polymer microparticles through droplet microfluidics;
[0026] Figure 3 The preparation process of PLGA microspheres in Example 1 and its temperature-dependent morphological characteristics;
[0027] Figure 4 This is a study on the diversity of microsphere morphologies synergistically regulated by polymer type and temperature in Example 2;
[0028] Figure 5 Figure 3 shows the effect of PVA concentration on the morphology of PLGA microspheres;
[0029] Figure 6 Figure 4 shows the regulation of microparticle morphology by six two-component polymers;
[0030] Figure 7 Figure 5 shows the effect of polymer ratio (PS / PLGA) on microparticle morphology.
[0031] Figure 8 This is a graph showing the effect of temperature on the morphology of microparticles in the PS:PLGA = 0.5:1.0 system in Example 5;
[0032] Figure 9 This is a graph showing the effect of PVA concentration on microparticle morphology in the PS:PLGA = 0.5:0.5 system in Example 5;
[0033] Figure 10 This is a graph showing the effect of polymer ratio on the morphology of three-component polymer microspheres in Example 6;
[0034] Figure 11 This is a diagram showing the effects of polymer ratio and temperature on the morphology of four-component microspheres in Example 7. DETAILED DESCRIPTION
[0035] In order to enable those skilled in the art to better understand the technical solution of the invention, the present invention is further described in detail below in conjunction with specific implementation methods.
[0036] Examples 1 to 6 provide a method for preparing heteromorphic polymer microparticles (eg Figure 2 ), specifically including the following steps:
[0037] S1. preparing an inner oil phase (dispersed phase) and an outer aqueous phase (continuous phase), wherein the inner oil phase is a chloroform solution containing a solute, wherein the solute includes one or more of polylactic-co-glycolic acid (PLGA, molecular weight 10,000-20,000), polyvinyl acetate (PVAc, molecular weight 50,000), polymethyl methacrylate (PMMA, molecular weight 15,000), and polystyrene (PS, molecular weight 192,000); and the outer aqueous phase is a polyvinyl alcohol (PVA) aqueous solution (polyvinyl alcohol having a degree of alcoholysis of 87-89% and a molecular weight of 13,000-23,000);
[0038] S2. Inject the inner oil phase into the organic phase microchannel of the droplet microfluidic chip through an external syringe pump, and inject the outer aqueous phase into the aqueous phase microchannel of the droplet microfluidic chip. By adjusting the flow rates of the inner oil phase and the outer aqueous phase (the inner oil phase is injected into a 500 μL microinjector at a flow rate of 400 μL / h; the outer aqueous phase is injected into a 5 mL plastic syringe at a flow rate of 1200 μL / h), microdroplets of oil-in-water morphology of the same particle size are obtained, and the samples are collected in a collection container of PVA solution;
[0039] S3. The collected micro-droplets are placed in a constant temperature box and kept still at a constant temperature until the organic solvent in the inner oil phase is completely evaporated to obtain polymer micro-particles.
[0040] The characterization method of the microparticles prepared in Examples 1 to 6 is as follows:
[0041] 1. Use Image J software to measure the particle size of microdroplets and microspheres;
[0042] 2. Observe the morphology of microparticles by scanning electron microscopy.
[0043] Example 1
[0044] This example investigates the effect of temperature on the morphology of PLGA microspheres, and the detailed process is as follows:
[0045] The inner oil phase is a chloroform solution containing solute PLGA, the PLGA concentration is 1.0% (w / v), and the outer aqueous phase is a 5.0% (w / v) PVA solution. The inner oil phase is sheared by the outer aqueous phase in the microchannel to form microdroplets with a particle size of about 145 μm (such as Figure 3 a), the CV value of the microdroplets was 2.8%, and the microdroplets were placed in a constant temperature box at 5°C, 20°C, and 30°C for about 48 hours to wait for the organic solvent in the microdroplets to evaporate completely, and then PLGA microparticles (such as Figure 3 b,c).
[0046] The particle size and morphology of PLGA microparticles were characterized. Figure 3It can be seen that the particle sizes of the polymer microparticles prepared at 5°C, 20°C, and 30°C are 32.8μm, 32.1μm, and 31.8μm, respectively, and the CV values are 4.1%, 4.1%, and 4.0%, respectively (the particle size distribution and change rate of droplets and microspheres are shown in Figure 2). Figure 3 d). The morphology of PLGA microspheres is significantly regulated by the preparation temperature. As the constant temperature increases (5℃-30℃), the number of surface pits and internal pore structures of the prepared microspheres increases significantly ( Figure 3 e1-e3, f1-f3). SEM characterization shows that the surface of the microspheres prepared at 30℃ presents a dense pit structure ( Figure 3 f3), the pit structure increases and becomes larger with increasing temperature ( Figure 3 g1-g3). Cross-sectional analysis ( Figure 3 h1-h3) reveal that the internal porosity of microspheres treated at high temperature (30°C) is significantly higher than that of low temperature (5°C) samples, and the internal pores increase with increasing temperature.
[0047] Example 2
[0048] This example systematically investigates the synergistic regulatory effects of polymer types (PVAc, PMMA, PS) and temperatures (5°C, 20°C, 30°C) on the microsphere morphology. Figure 4 ), the specific operations are as follows:
[0049] The preparation process of microparticles is the same as that of Example 1, except that the internal oil phase solutes are PVAc, PMMA, and PS, and the concentration is 1% (w / v). Characterization shows that PVAc, PMMA, and PS droplets are monodisperse under the same conditions ( Figure 4 a, b). Temperature-dependent morphological evolution of PVAc microspheres. Figure 4 As shown in c: the surface of the microspheres prepared at 5°C is relatively smooth, and as the temperature increases, the pores on the surface of the microspheres gradually increase; the microspheres prepared by PMMA droplets under the above different temperature conditions all show a structure with pores on the surface, but the change of this structure with temperature is not obvious in the SEM image. Only the light and dark distribution of the microspheres can be seen to have changed significantly in the optical micrograph ( Figure 4 d); Temperature-dependent morphological evolution of PS microspheres Figure 4 As shown in Figure e, the surface of the PS microspheres prepared at 5°C is relatively smooth, with only a few shallow pits. As the temperature increases (20°C, 30°C), obvious and gradually increasing pores appear on the surface of the microspheres.
[0050] Example 3
[0051] This example investigates the regulatory effect of PVA concentration (0.5%, 2.0%, 5.0%) on the morphology of PLGA microspheres ( Figure 5 ), the specific operations are as follows:
[0052] The inner oil phase is chloroform containing solute PLGA, with a PLGA concentration of 1.0% (w / v); the outer aqueous phase is 0.5%, 2.0%, and 5.0% (w / v) PVA solution. The inner oil phase is sheared by the outer aqueous phase in the microchannel to form microdroplets with a particle size of about 145 μm (such as Figure 5 a) Place in a 30°C constant temperature box for 48 hours to allow the organic solvent in the microdroplets to evaporate completely to obtain monodispersed PLGA microspheres. Figure 5 As shown in Figures b and c, the surfaces of the microspheres prepared at low PVA concentrations (0.5% and 2.0%) have more pores and pits, and show obvious differences in light and dark in the optical microscopic images; the surfaces of the microspheres prepared at high PVA concentrations (5.0%) have significantly fewer pores and pits, and are almost smooth, showing a relatively uniform distribution of light and dark in the optical microscopic images, reflecting that the internal structure of the microspheres prepared under the modified conditions is more ordered and regular.
[0053] Example 4
[0054] This example investigates the effects of six two-component polymer combinations (PLGA+PS, PLGA+PVAc, PLGA+PMMA, PVAc+PMMA, PVAc+PS, PMMA+PS) on the regulation of microparticle morphology (e.g. Figure 6 ), the specific operations are as follows:
[0055] The inner oil phase was chloroform containing the solutes PLGA+PS, PLGA+PVAc, PLGA+PMMA, PVAc+PMMA, PVAc+PS, and PMMA+PS. The concentration of each polymer was 0.5% (w / v), and the concentration ratio of the two components was 0.5:0.5. The outer aqueous phase was a 5.0% (w / v) PVA solution. The inner oil phase was sheared by the outer aqueous phase in the microchannel to form microdroplets with a particle size of approximately 145 μm, showing good monodispersity (such as Figure 6 a), placed in a 5°C constant temperature box for 48 hours to ensure that the polymer phase separation in the microdroplets is complete and the organic solvent is completely evaporated, thereby obtaining microparticles with highly uniform morphology ( Figure 6bd). The results showed that different polymer combinations could form microparticles with diverse morphologies through phase separation induction. Specifically, PLGA+PS formed dumbbell-shaped microparticles with a smooth surface on one side and pits and protrusions on the other side. PLGA+PVAc produced raspberry-like porous microparticles with pores and large bulges on one side and numerous tiny protrusions on the other side. PLGA+PMMA formed rough snowman-shaped microparticles with large irregular bulges on one side and numerous tiny protrusions on the other side. PVAc+PMMA formed microspheres with a porous surface. No obvious phase separation structure was observed in SEM images, but distinct light and dark zoning was observed in optical micrographs. PVAc+PS formed dumbbell-shaped microparticles with pores and pits on both sides. PMMA+PS formed spindle-shaped microparticles with porous surfaces, and optical micrographs showed a clear phase separation structure.
[0056] Example 5
[0057] This example systematically investigates the regulatory effects of polymer ratio, temperature and PVA concentration on the morphology of PS / PLGA microparticles ( Figure 7-9 Scanning electron microscopy (SEM) characterization (PS: orange, PLGA: green) revealed the following key findings:
[0058] The preparation process of microparticles is the same as that of Example 4, and the concentration of PVA solution is 5% (w / v). The polymer ratio controls the morphology ( Figure 7 ): At 5°C, changes in the PS / PLGA ratio significantly affect the microparticle morphology: when the PS ratio is high (1:0.5), an asymmetric double-spherical structure is formed, with clear boundaries between the orange PS area and the green PLGA area, the PS end surface has many protrusions of different sizes, and the PLGA end surface is smooth; when the PLGA ratio is high (0.5:1), an asymmetric double-spherical structure is also formed, the PLGA end surface is smooth but accompanied by several larger spherical protrusions, and the PS end still has many protrusions of different sizes; when the content is the same (0.5:0.5), the two phases present a typical Janus structure, the PS end surface has many protrusions and concave holes, and the PLGA end surface is smooth.
[0059] Temperature control of morphology ( Figure 8 In a PS:PLGA ratio of 0.5:1.0, increasing temperature significantly altered the phase separation behavior: at 5°C, a typical double-spherical structure formed, with clear phase separation; at 20°C, a snowman-shaped structure emerged, with a blurred phase interface; and at 30°C, the compatibility of the two phases increased, significantly reducing the degree of phase separation. Furthermore, the surface of the prepared microspheres became smoother with increasing static constant temperature.
[0060] Effect of PVA concentration ( Figure 9): In the PS:PLGA=0.5:0.5 system, microspheres were prepared at 5°C: the microspheres prepared under different PVA concentrations all showed a clear Janus structure, which became more obvious with the increase of PVA concentration, manifested as a more intense phase separation; the PS ends of all prepared microspheres showed a smooth surface, while the PLGA end surfaces showed a composite structure of protrusions and pits, and the number of protrusions gradually increased with the increase of PVA concentration.
[0061] Example 6
[0062] This example investigates the effect of polymer ratio on the regulation of microparticles in a three-component system ( Figure 10 ), the specific operations are as follows:
[0063] The microparticle preparation process was the same as in Example 4. The internal oil phase solutes consisted of PVAc+PS+PMMA (at a PVAc:PS:PMMA ratio of 0.5:0.5:0.5), PVAc+PS+PLGA (at a PVAc:PS:PLGA ratio of 0.5:0.5:0.25), PVAc+PS+PLGA (at a PVAc:PS:PLGA ratio of 0.5:0.5:0.5), and PVAc+PS+PLGA (at a PVAc:PS:PLGA ratio of 0.5:0.5:1.0). The external aqueous phase consisted of a 5.0% (w / v) PVA solution. The internal oil phase was sheared by the external aqueous phase in the microchannel to form microdroplets approximately 145 μm in size. After the organic solvent in the microdroplets evaporated completely in a 5°C incubator for 48 hours, the resulting microparticles exhibited various shapes, including snowman, raspberry, popcorn, and trihedron. The diverse morphologies of the particles stem from differences in polymer polarity and solubility.
[0064] Example 7:
[0065] This example investigates the effects of polymer ratio and temperature on the regulation of microparticles in a four-component system ( Figure 11 ), the specific operations are as follows:
[0066] The preparation process of microparticles is the same as that of Example 4, and the polymer ratio is regulated: the inner oil phase solutes are PVAc+PS+PLGA+PMMA, and the concentration ratios are PVAc:PS:PLGA:PMMA=0.5:0.5:0.5:0.1, PVAc:PS:PLGA:PMMA=0.5:0.5:0.5:0.3, and PVAc:PS:PLGA:PMMA=0.5:0.5:0.5:0.5; the outer aqueous phase is a 5.0% (w / v) PVA solution. The inner oil phase is sheared by the outer aqueous phase in the microchannel to form microdroplets with a particle size of about 145 μm. After being placed in a 5°C constant temperature box for 48 hours and the organic solvent in the microdroplets is completely evaporated, the formed microparticles all show a raspberry shape with pores and uneven protrusions on the surface. As the PMMA content increases (0.1-0.5), the number of surface protrusions of the obtained microspheres gradually decreases, but the size of the protrusions gradually increases ( Figure 10 a, b); Temperature control: Taking PVAc:PS:PLGA:PMMA=0.5:0.5:0.5:0.3 as an example, when the constant temperature is raised to 20 or 30℃, the degree of phase separation of the particles decreases, the surface protrusions disappear, and the surface has fine pores ( Figure 10 c1, d1) and smooth surface ( Figure 10 c2, d2) are spherical. It is difficult to directly observe the phase separation boundary in the SEM image ( Figure 10 d), while the phase separation structure is clearly seen in the optical micrograph energy lines ( Figure 10 c); In summary, increasing temperature and PMMA content both enhance the phase separation of the four-component microspheres, leading to the formation of microspheres with more regular structures. By rationally controlling the PMMA content and temperature to control the degree of phase separation of the four components, a fine-tuned structure from porous and rough to smooth, spherical shapes can be achieved.
[0067] The above are merely preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be construed as limiting the present invention, and the scope of protection of the present invention should be determined by the scope defined in the claims. Persons skilled in the art will appreciate that improvements and modifications may be made without departing from the spirit and scope of the present invention, and such improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for preparing heteromorphic polymer microparticles, characterized in that: include: A polymer solution is used as the inner oil phase and a polyvinyl alcohol aqueous solution is used as the outer water phase. Microdroplets are generated using a droplet microfluidic chip and placed under constant temperature conditions to evaporate the solvent. By regulating the composition and proportion of the polymer, the concentration of the polyvinyl alcohol aqueous solution and the constant temperature, the microdroplets are induced to undergo controllable phase separation or interfacial self-assembly, and finally solidify into heteromorphic polymer microparticles.
2. The method for preparing heteromorphic polymer microparticles according to claim 1, characterized in that: The polymer is selected from any one or more of PLGA, PVAc, PMMA, and PS.
3. The method for preparing heteromorphic polymer microparticles according to claim 1, characterized in that: The concentration of the polymer-containing solution is 0.5% to 1.0% w / v.
4. The method for preparing heteromorphic polymer microparticles according to claim 1, characterized in that: The concentration of the polyvinyl alcohol aqueous solution is 0.5% to 5.0% w / v.
5. The method for preparing heteromorphic polymer microparticles according to claim 1, characterized in that: The microdroplets are monodisperse oil-in-water microdroplets.
6. The method for preparing heteromorphic polymer microparticles according to claim 1, characterized in that: The solvent in the inner oil phase is selected from chloroform or an organic solvent having similar physical and chemical properties to chloroform.
7. The method for preparing heteromorphic polymer microparticles according to claim 1, characterized in that: The process of generating microdroplets using the droplet microfluidic chip is as follows: injecting the inner oil phase into the organic phase microchannel of the droplet microfluidic chip, injecting the outer water phase into the water phase microchannel of the droplet microfluidic chip, and obtaining microdroplets of the same particle size by adjusting the flow rates of the inner oil phase and the outer water phase.
8. The method for preparing heteromorphic polymer microparticles according to claim 7, characterized in that: The flow rate of the inner oil phase was 400 μL / h, and the flow rate of the outer water phase was 1200 μL / h.
9. The method for preparing heteromorphic polymer microparticles according to claim 1, characterized in that: The temperature of the constant temperature condition is 5°C to 30°C.
10. The method for preparing heteromorphic polymer microparticles according to any one of claims 1 to 9, characterized in that: The morphology of the heteromorphic polymer microparticles is selected from any one or more of surface pits, internal porosity, dumbbell-shaped structure, raspberry-shaped porous structure, snowman-shaped structure, porous spherical structure, porous dumbbell-shaped structure, spindle-shaped structure, double spherical structure, typical Janus structure, popcorn-shaped structure, trihedral structure, and spherical-like structure.