An apparatus and method for evaluating evaporation-induced foaming behavior of a polymer solution

Abstract

The application discloses an evaluation device and a test method for polymer solution evaporation induced foaming behavior, and the evaluation device comprises an electric heating jacket, a quartz round-bottom flask, a bubble breaking member, a quartz sleeve, a spherical condenser, a buffer tank, a horizontal flow pump, a preheating coil pipe and a high-speed camera. The test method and the evaluation device can realize polymer solution evaporation induced foaming under a controllable process by adjusting the concentration of the polymer solution, the operating pressure and the heating power, can capture the bubble layer behavior of the polymer solution system foaming process under different conditions, can further convert the foaming behavior induced by thermodynamic instability into quantitative bubble layer process evolution data, and can reveal the mass transfer law of the polymer solution evaporation process, so as to provide guidance for industrialized polymer separation process technology, equipment design selection and process operation optimization.

Description

Technical Field

[0001] This invention relates to the field of polymer separation engineering technology, and specifically to an evaluation device and testing method for the foaming behavior induced by evaporation of polymer solutions. Background Technology

[0002] Polymer devolatilization refers to the process of separating low molecular weight components from a polymer system. It is typically divided into three stages based on the content of volatile organic compounds: flash devolatilization, foaming devolatilization, and diffusion devolatilization. When the volatile content in the polymer decreases to the range of 5% to 20%, heat and mass transfer are driven by the nucleation, growth, movement, coalescence, and collapse of bubbles in the polymer solution, achieving separation of the volatiles from the polymer. This stage is generally called foaming devolatilization.

[0003] In industrial devolatilization process research, it is often necessary to select suitable process conditions and equipment based on the foaming characteristics of the polymer solution. Especially in the foaming devolatilization stage, the foaming performance of the polymer and its compatibility with the process conditions and equipment directly affect the success of the research. Therefore, evaluating the foaming performance of the polymer solution is crucial for the study of polymer devolatilization processes.

[0004] The foaming process of polymer solutions involves mass transfer and heat transfer, and is affected not only by operating conditions such as temperature, pressure, stirring, and thermal power, but also by the properties of the solution itself, such as homogeneity and viscoelasticity. With many influencing factors and complex mechanisms, it is difficult to study. Therefore, the study of the evolution of the overall bubble layer during the foaming process has become an important entry point for exploring the foaming process of polymer solutions.

[0005] In summary, a low-cost, simple, efficient, and accurate technical means is still lacking to investigate the evolution of the bubble layer during the foaming process of polymer solution systems, providing guidance for industrial polymer separation technology, equipment design and selection, and process operation optimization. Based on this problem, and aiming to investigate the evolution of the bubble layer during the foaming and devolatilization process of polymer solution systems, this invention provides an evaluation device and testing method for the evaporation-induced foaming behavior of polymer solutions. Summary of the Invention

[0006] The main purpose of this invention is to provide an evaluation device and testing method for the evaporation-induced foaming behavior of polymer solutions, so as to study the evolution law of the bubble layer during the foaming and devolatilization process of polymer solutions.

[0007] To achieve the above objectives, the present invention provides the following technical solution: An evaluation device for the evaporation-induced foaming behavior of a polymer solution, the evaluation device comprising an electric heating mantle, a quartz round-bottom flask, a foam-breaking component, a quartz sleeve, a spherical condenser, a buffer tank, a horizontal flow pump, a preheating coil, a thermometer, a pressure gauge, a vacuum valve, a pressure relief valve, a ball valve, and a high-speed camera; The electric heating mantle has a heating power of 0~300W, the quartz round bottom flask has a volume of 280~360mL and an inner diameter of 40~60mm at the mouth, the quartz sleeve has an inner diameter of 40~60mm and a height of 650~950mm, and the three are erected vertically on the ground on the same straight line. Preferably, the heating mantle has a heating power of 100~250W, the quartz round-bottom flask has a volume of 320~340mL and an inner diameter of 48~52mm, the quartz sleeve has an inner diameter of 48~52mm and a height of 750~850mm, and the three are erected vertically on the ground on the same straight line. The quartz round-bottom flask has two additional openings at the top, serving as a reflux inlet and a thermometer insertion port. The quartz round-bottom flask is detachable and is connected to the lower opening of the quartz sleeve through a PTFE gasket and a clamp. The quartz sleeve is hollow, allowing the polymer solution bubble layer to grow and evolve; The quartz sleeve jacket contains circulating hot oil, which is connected to a temperature-controlled oil bath. The bubble-breaking component is provided at the bottom end of the quartz sleeve; The quartz sleeve is marked with graduations.

[0008] In the above text, the quartz sleeve jacket contains circulating hot oil, which is connected to a temperature-controlled oil bath to maintain the system temperature and create a near-insulated environment inside the sleeve.

[0009] The bubble-breaking component is provided at the bottom of the quartz sleeve. The bubble-breaking component is a rotatable bubble-breaking component used to eliminate bubbles generated before the process conditions stabilize and to prevent bubbles from entering the vertical quartz sleeve prematurely.

[0010] The quartz sleeve is marked with graduations to monitor the height of the bubble layer evolution.

[0011] Preferably, the spherical condenser tube is connected to cooling water at both the top and bottom for condensing the evaporated solvent; the inlet of the spherical condenser tube is connected to the top of the quartz sleeve by a PTFE gasket and a clamp.

[0012] Preferably, the outlet of the spherical condenser is connected to the buffer tank with a volume of 200~400mL. The buffer tank is used to collect the solvent condensed in the spherical condenser and to ensure that the total vaporization amount of the solvent in the experimental system is consistent with the reflux amount by controlling the stability of the liquid level in the buffer tank during the experiment, thereby ensuring that the polymer solution in the quartz round bottom flask maintains a constant concentration and achieving overall system steady state.

[0013] Preferably, the outlet of the buffer tank is connected to the advection pump, the advection pump having a flow rate of 60~100mL / min and a maximum pressure of 10MPa, used to transport the solvent in the buffer tank back to the heating system according to the flow rate requirement.

[0014] Preferably, the outlet of the advection pump is connected to the preheating coil, which is used to preheat the reflux liquid so that it is at the same temperature as the polymer solution in the quartz round-bottom flask, thereby achieving overall system stability.

[0015] A method for testing the evaporation-induced foaming behavior of a polymer solution includes the following steps: (1) Prepare a polymer solution of the required concentration in advance; (2) Transfer the prepared polymer solution into a quartz round-bottom flask, add a small amount of boiling stones, and then connect the various parts of the apparatus in sequence; (3) Introduce air into the nitrogen replacement device and repeat at least three times. Then add the corresponding polymer solvent into the buffer tank, record the liquid level, and mark the liquid level position. (4) Open the bubble-breaking component, turn on the heating system, and adjust the output power of the electric heating mantle to gradually increase the temperature of the experimental system until the solution boils. (5) Adjust the oil temperature of the oil bath circulation in the quartz sleeve to keep it consistent with the temperature of the polymer solution in order to construct a pseudo-insulation environment; (6) Turn on the cooling water of the spherical condenser to condense the solvent vapor, and adjust the temperature of the preheating coil to match the temperature displayed on the thermometer; (7) Adjust the flow rates of the ball valve and the parallel flow pump to keep the solvent level in the buffer tank consistent with the initial level until the reflux flow rate stabilizes; (8) Open the vacuum valve and use a vacuum pump to pump the system pressure inside the device to the required vacuum level; (9) Retract the bubble-breaking component. At this time, the bubble layer begins to gradually expand. Turn on the high-speed camera to record the change in the height of the bubble layer over time. (10) When the bubble layer expands to its highest point and the height of the bubble layer no longer changes, use a high-speed camera to record the state of the bubbles in the bubble layer at this time.

[0016] Throughout the testing process, attention must be paid to the pressure gauge and pressure safety valve to prevent excessive pressure within the device from damaging it.

[0017] Preferably, the polymer in the polymer solution is selected from one of polyolefin elastomer (POE), olefin block copolymer (OBC), cyclic olefin copolymer (COC), ethylene-vinyl acetate copolymer (EVA), polylactic acid (PLA), polystyrene (PS), polybutylene succinate (PBS), and polymethyl ethylene carbonate (PPC).

[0018] Preferably, the solvent of the polymer solution is selected from one of the following: n-hexane, n-pentane, n-heptane, cyclohexane, 1-butene, 1-hexene, 1-octene, caprolactam, water, and lactide.

[0019] Preferably, the process of the bubble layer expanding in volume over time is described as follows: In the formula: V f (t) represents the volume of the bubble layer at time t (cm³). 3 D is the diameter of the experimental setup, and H(t) is the height of the bubble layer at time t (cm).

[0020] Preferably, the concentration of the polymer solution is 0.1-20%, the operating pressure is 10-200 kPa, the heating power is 0-300 W, and the inert gas is selected from nitrogen, helium, and carbon dioxide.

[0021] More preferably, the concentration of the polymer solution is 1-10%, the operating pressure is 50-150 kPa, the heating power is 100-250 W, and the inert gas is selected from nitrogen, helium, and carbon dioxide.

[0022] Due to the application of the above technical solution, the present invention has significant advantages and beneficial effects compared with the prior art, specifically reflected in the following aspects: 1. This invention enables the visualization and monitoring of foaming behavior in polymer solutions, transforming the abstract and thermodynamically unstable foaming behavior into specific and quantitative data on the evolution of the bubble layer process. This solves the problem of difficulty in monitoring and quantifying the bubble layer and reveals potential mass transfer laws.

[0023] 2. This invention can monitor the foaming behavior of polymer solutions under different concentrations, vacuum levels, and power conditions, explore the evolution law of bubble layers under different process conditions, and provide guidance for industrial polymer separation technology, equipment design and selection, and process operation optimization.

[0024] 3. The technical means provided by this invention have the advantages of being more cost-effective, simple, efficient and accurate. Attached Figure Description

[0025] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, some of the drawings in the following description are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the overall structure of the device in Embodiment 1 of the present invention; Figure 2 This is a diagram showing the overall evolution of the bubble layer in Embodiment 1 of the present invention; Figure 3 This is a diagram showing the evolution of the axial dimensions of the bubble layer in Embodiment 2 of the present invention; Figure 4 This is a graph showing the volume change of the bubble layer in polymer solutions of different concentrations in Example 3 of the present invention. Figure 5 This is a diagram showing the bubble size distribution under different vacuum conditions in Example 4 of the present invention; Figure 6 This is a quantitative trend diagram of the expansion volume of the bubble layer over time under different vacuum conditions in Embodiment 4 of the present invention.

[0027] Among them, 1-Heating mantle; 2-Quartz round-bottom flask; 3-Bubble-breaking component; 4-Quartz sleeve; 5-Spherical condenser; 6-Buffer tank; 7-Horizontal flow pump; 8-Preheating coil; 9-Thermometer; 10-Pressure gauge; 11-Vacuum valve; 12-Pressure safety valve; 13-Ball valve; 14-High-speed camera. Detailed Implementation

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0029] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0030] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing the invention and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0031] Furthermore, in addition to indicating direction or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in certain situations to indicate a dependency or connection. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0032] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0033] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0034] Example 1 See appendix Figure 1 and appendix Figure 2 This embodiment provides an evaluation device and test method for the evaporation-induced foaming behavior of polymer solutions; An evaluation device for the evaporation-induced foaming behavior of a polymer solution, the evaluation device comprising an electric heating mantle 1, a quartz round-bottom flask 2, a bubble-breaking component 3, a quartz sleeve 4, a spherical condenser 5, a buffer tank 6, a horizontal flow pump 7, a preheating coil 8, a thermometer 9, a pressure gauge 10, a vacuum valve 11, a pressure safety valve 12, a ball valve 13, and a high-speed camera 14. Furthermore, the electric heating mantle 1, the quartz round-bottom flask 2, and the quartz sleeve 4 are all mounted vertically on the same straight line. Furthermore, the top of the quartz round-bottom flask 2 has two additional openings, serving as a reflux inlet and a thermometer 9 insertion port; Furthermore, the quartz round-bottom flask 2 is detachable and is connected to the lower opening of the quartz sleeve 4 through a polytetrafluoroethylene gasket and a clamp. Furthermore, the quartz sleeve 4 is hollow, allowing the polymer solution bubble layer to grow and evolve; Furthermore, the quartz sleeve 4 is fitted with circulating hot oil, which is connected to a temperature-controlled oil bath to maintain the system temperature and create a near-insulated environment inside the sleeve. Furthermore, the bottom end of the quartz sleeve 4 is provided with the bubble-breaking component 3, which is a rotatable bubble-breaking component, used to eliminate bubbles generated before the process conditions stabilize and prevent bubbles from entering the vertical quartz sleeve in advance. Furthermore, the quartz sleeve 4 is marked with graduations to monitor the height of the bubble layer evolution; Furthermore, the upper and lower ends of the spherical condenser are connected to cooling water for condensing the evaporated solvent; the inlet of the spherical condenser is connected to the upper end of the quartz sleeve by a PTFE gasket and a clamp. Furthermore, the outlet of the spherical condenser 5 is connected to the buffer tank 6. The buffer tank 6 is used to collect the solvent condensed in the spherical condenser 5, and to ensure that the total vaporization amount of the solvent in the experimental system is kept consistent with the reflux amount by controlling the stability of the liquid level in the buffer tank 6 during the experiment, thereby ensuring that the polymer solution in the quartz round bottom flask 2 maintains a constant concentration and achieves overall system steady state. Furthermore, the outlet of the buffer tank 6 is connected to the horizontal flow pump 7, which is used to transport the solvent in the buffer tank 6 back to the heating system according to the flow rate requirement; Furthermore, the outlet of the advection pump 7 is connected to the preheating coil 8, which is used to preheat the reflux liquid so that it is at the same temperature as the polymer solution in the quartz round-bottom flask 2, thereby achieving overall system stability. A test method for the evaporation-induced foaming behavior of a polymer solution, specifically including the following steps: (1) Using POE as the polymer and n-hexane as the solvent, weigh and heat the mixture to prepare a polymer solution with the required concentration of 1%; (2) Transfer the prepared polymer solution into the quartz round-bottom flask 2, add a small amount of boiling stones, and then connect the various parts of the device in sequence. (3) Introduce the air into the nitrogen replacement device, repeat three times, then add the corresponding polymer solvent into the buffer tank 6, record the liquid level height, and mark the liquid level position; (4) Open the bubble-breaking component 3, turn on the heating system, and adjust the output power of the electric heating mantle 1 to 128W so that the temperature of the experimental system gradually rises until the solution boils. (5) Adjust the oil temperature of the oil bath circulation in the quartz sleeve 4 to keep it consistent with the temperature of the polymer solution in order to construct a pseudo-insulation environment; (6) Turn on the cooling water in the spherical condenser 5 to condense the solvent vapor, and adjust the temperature of the preheating coil 8 to match the temperature displayed by the thermometer 9; (7) Adjust the flow rates of ball valve 13 and parallel flow pump 7 to keep the solvent level in buffer tank 6 consistent with the initial level until the reflux flow rate stabilizes; (8) Pay attention to pressure gauge 10 and pressure safety valve 12 to prevent excessive pressure in the system from damaging the device; (9) Open the vacuum valve 11 and use a vacuum pump to pump the system pressure inside the device to the required vacuum level; (10) Retract the bubble-breaking component 3 and record this time as time 0. At this time, the bubble layer begins to gradually expand. Turn on the high-speed camera 14 and record the change of bubble layer height over time. (11) When the bubble layer expands to its highest point and the height of the bubble layer no longer changes, use a high-speed camera to record the state of the bubbles in the bubble layer at this time.

[0035] Example 2 This embodiment provides an evaluation device and testing method for the evaporation-induced foaming behavior of polymer solutions; This embodiment is based on Example 1, except that the polymer is changed to PS and the solvent is changed to styrene. The required 3% (w / w) polymer solution is prepared by weighing, heating, and stirring. Other implementation methods are the same as in Example 1. The average bubble diameters in each region from bottom to top along the axial direction are 2.36 mm, 2.50 mm, 2.47 mm, 2.99 mm, 3.48 mm, and 4.32 mm, respectively. The evolution of the axial dimensions of the bubble layer is shown in the appendix. Figure 3 .

[0036] Example 3 This embodiment provides an evaluation device and testing method for the evaporation-induced foaming behavior of polymer solutions; This embodiment is based on Example 1, except that the polymer is changed to OBC and the solvent is changed to cyclohexane. Polymer solutions with the required mass concentrations of 1%, 3%, 5%, and 7% are prepared by weighing, heating, and stirring. Other implementation methods in this embodiment are the same as in Example 1. Under these conditions, the maximum expansion height of the bubble layer is 10.1 cm, 13.7 cm, 26.9 cm, and 32.3 cm, respectively, and the maximum expansion volume of the bubble layer is 198.21 cm³. 3 268.86cm 3 527.91cm 3 633.89cm 3 For changes in bubble layer expansion volume of polymer solutions of different concentrations, please refer to Appendix. Figure 4 .

[0037] Example 4 This embodiment provides an evaluation device and testing method for the evaporation-induced foaming behavior of polymer solutions; (1) Using POE as the polymer and cyclohexane as the solvent, weigh and heat the mixture to prepare a polymer solution with the required concentration of 3%; (2) Transfer the prepared polymer solution into a quartz round-bottom flask, add a small amount of boiling stones, and then connect the various parts of the apparatus in sequence; (3) Introduce nitrogen to replace the air inside the device, repeat three times, then add the corresponding polymer solvent into the buffer tank, record the liquid level, and mark the liquid level position; (4) Open the bubble-breaking component, turn on the heating system, and adjust the output power of the electric heating mantle to 200W so that the temperature of the experimental system gradually rises until the solution boils. (5) Adjust the oil temperature of the oil bath circulation in the quartz sleeve to keep it consistent with the temperature of the polymer solution in order to construct a pseudo-insulation environment; (6) Turn on the cooling water of the spherical condenser to condense the solvent vapor, and adjust the temperature of the preheating coil to match the temperature displayed on the thermometer; (7) Adjust the flow rates of the ball valve and the parallel flow pump to keep the solvent level in the buffer tank consistent with the initial level until the reflux flow rate stabilizes; (8) Pay attention to pressure gauges and pressure safety valves to prevent excessive pressure in the system from damaging the device; (9) Open the vacuum valve and use the vacuum pump to pump the system pressure inside the device to and stabilize it at 120 kPa, 110 kPa, 90 kPa and 70 kPa respectively; (10) Retract the bubble-breaking component and record this time as time 0. At this time, the bubble layer begins to gradually expand. Turn on the high-speed camera and record the change of bubble layer height over time. (11) When the bubble layer expands to its highest point and the bubble layer height no longer changes, the bubble state in the bubble layer is recorded by a high-speed camera. The average bubble diameters in this series are 1.71 mm, 2.30 mm, 3.30 mm, and 3.62 mm, respectively, and the bubble layer expansion rates are 4.50 cm. 3 / s, 6.01cm 3 / s, 24.32cm 3 / s, 63.69cm 3 / s, the bubble size distribution and bubble layer expansion volume quantification curves under different vacuum conditions are shown in the appendix. Figure 5 and attached Figure 6 .

[0038] Comparative Example 1 This comparative example is based on Example 3, with the polymer system mass concentration adjusted to 9%. Other implementation methods in this comparative example are the same as in Example 3. Under these conditions, the maximum height of the bubble layer expansion is 37.6 cm, and the bubble layer expansion rate is 737.90 cm. 3 .

[0039] Comparative Example 2 This comparative example is based on Example 4, with the system pressure adjusted to 50 kPa. Other implementation methods in this comparative example are the same as in Example 4. Under these conditions, the average bubble diameter is 4.08 mm, and the bubble layer expansion rate is 145.80 cm⁻¹. 3 / s.

[0040] As can be seen from the examples, comparative examples, and accompanying drawings, the present invention can visualize and monitor the foaming behavior of polymer solutions, transforming the abstract and thermodynamically unstable foaming behavior into specific and quantitative data on the evolution of the bubble layer process. This solves the problem of difficulty in monitoring and quantifying the bubble layer, reveals potential mass transfer laws, and enables the monitoring of the foaming behavior of polymer solutions under different concentrations, vacuum levels, and power conditions. It explores the evolution laws of the bubble layer under different process conditions, providing guidance for industrial polymer separation process technology, equipment design and selection, and process operation optimization.

[0041] The above-described embodiments are merely four examples of implementation of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. An evaluation device for the evaporation-induced foaming behavior of a polymer solution, characterized in that, The evaluation device includes an electric heating mantle, a quartz round-bottom flask, a bubble-breaking component, a quartz sleeve, a spherical condenser, a buffer tank, a horizontal flow pump, a preheating coil, a thermometer, a pressure gauge, a vacuum valve, a pressure safety valve, a ball valve, and a high-speed camera. The heating mantle is built into the quartz round-bottom flask; The electric heating mantle has a heating power of 0~300W, the quartz round bottom flask has a volume of 280~360mL and an inner diameter of 40~60mm at the mouth, the quartz sleeve has an inner diameter of 40~60mm and a height of 650~950mm, and the three are erected vertically on the ground on the same straight line. The quartz round-bottom flask has two additional openings at the top, serving as a reflux inlet and a thermometer insertion port. The quartz round-bottom flask is detachable and is connected to the lower opening of the quartz sleeve through a PTFE gasket and a clamp. The quartz sleeve is hollow, allowing the polymer solution bubble layer to grow and evolve; The quartz sleeve jacket contains circulating hot oil, which is connected to a temperature-controlled oil bath. The bubble-breaking component is provided at the bottom end of the quartz sleeve; The quartz sleeve is marked with graduations; A high-speed camera is positioned directly in front of the quartz sleeve; The spherical condenser tube is connected above the quartz sleeve; The spherical condenser tube is connected to cooling water at both the top and bottom for condensing the evaporated solvent; the inlet of the spherical condenser tube is connected to the top of the quartz sleeve by a PTFE gasket and a clamp. The outlet of the spherical condenser is connected to the buffer tank, which has a volume of 200~400mL, and the ball valve is installed on the inlet and outlet pipelines of the buffer tank; The outlet of the buffer tank is connected to the horizontal flow pump; the flow rate of the horizontal flow pump is 60~100mL / min, and the maximum pressure is 10Mpa; The preheating coil is connected to the outlet of the horizontal flow pump. The preheating coil is then connected back to the quartz round-bottom flask; The buffer tank is equipped with the pressure gauge, the vacuum valve, and the pressure safety valve.

2. A testing method using the evaluation device for polymer solution evaporation-induced foaming behavior as described in claim 1, characterized in that, Includes the following steps: (1) Prepare a polymer solution of the required concentration in advance; (2) Transfer the prepared polymer solution into a quartz round-bottom flask, add a small amount of boiling stones, and then connect the various parts of the apparatus in sequence; (3) Introduce air into the inert gas replacement device and repeat at least three times. Then add the corresponding polymer solvent into the buffer tank, record the liquid level, and mark the liquid level position. (4) Open the bubble-breaking component, turn on the heating system, and adjust the output power of the electric heating mantle to gradually increase the temperature of the experimental system until the solution boils. (5) Adjust the oil temperature of the oil bath circulation in the quartz sleeve to keep it consistent with the temperature of the polymer solution in order to construct a pseudo-insulation environment; (6) Turn on the cooling water of the spherical condenser to condense the solvent vapor, and adjust the temperature of the preheating coil to match the temperature displayed on the thermometer; (7) Adjust the flow rates of the ball valve and the parallel flow pump to keep the solvent level in the buffer tank consistent with the initial level until the reflux flow rate stabilizes; (8) Open the vacuum valve and use a vacuum pump to pump the system pressure inside the device to the required vacuum level; (9) Retract the bubble-breaking component. At this time, the bubble layer begins to gradually expand. Turn on the high-speed camera to record the change in the height of the bubble layer over time. (10) When the bubble layer expands to its highest point and the height of the bubble layer no longer changes, use a high-speed camera to record the state of the bubbles in the bubble layer at this time.

3. The test method for the evaporation-induced foaming behavior of a polymer solution according to claim 2, characterized in that, The polymer in the polymer solution is selected from one of the following: polyolefin elastomer, olefin block copolymer, cyclic olefin copolymer, ethylene-vinyl acetate copolymer, polylactic acid, polystyrene, polybutylene succinate, and polymethyl ethylene carbonate.

4. The test method for the evaporation-induced foaming behavior of a polymer solution according to claim 2, characterized in that, The solvent of the polymer solution is selected from one of the following: n-hexane, n-pentane, n-heptane, cyclohexane, 1-butene, 1-hexene, 1-octene, caprolactam, water, and lactide.

5. The test method for the evaporation-induced foaming behavior of a polymer solution according to claim 2, characterized in that, The process of the bubble layer expanding in volume over time is described as follows: In the formula: V f H(t) represents the volume of the bubble layer at time t, D represents the diameter of the experimental setup, and H(t) represents the height of the bubble layer at time t.

6. The test method for the evaporation-induced foaming behavior of a polymer solution according to claim 2, characterized in that, The concentration of the polymer solution is 0.1-20%, the operating pressure is 10-200 kPa, the heating power is 0-300 W, and the inert gas is selected from nitrogen, helium, and carbon dioxide.

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