Modularized micro-reaction system for synthesizing polycarboxylate superplasticizer

Abstract

The invention discloses a modular micro-reaction system for synthesis of a polycarboxylate superplasticizer, and relates to the technical field of synthesis of polycarboxylate superplasticizers, the system comprises the following components: a raw material supply module, a raw material mixing module, a molecular weight regulation and control module, a reaction curing module and a product storage module; according to the invention, modularized splitting and collaborative linkage of the whole synthesis process of the polycarboxylate superplasticizer are realized, all links are accurately controlled and efficiently linked, and the raw materials are stably and flexibly fed and efficiently mixed; molecular weight regulation and control are real-time and dynamic, performance consistency is improved, and intelligent upgrading is promoted; reaction curing and product storage are optimized, the product quality and production continuity are guaranteed, and the maintenance cost is reduced; the universality and the expandability are enhanced through the overall modular design, different requirements can be flexibly met, and technical support is provided for large-scale and high-quality production.

Description

Technical Field

[0001] This invention relates to the field of polycarboxylate superplasticizer synthesis technology, and more particularly to a modular microreaction system for the synthesis of polycarboxylate superplasticizers. Background Technology

[0002] Polycarboxylate superplasticizers, as core admixtures for high-performance concrete, significantly improve the fluidity, strength, and durability of concrete, and are widely used in infrastructure projects such as bridges, tunnels, and high-rise buildings. With the continuous upgrading of concrete performance requirements in engineering construction, the synthesis precision, product stability, and production efficiency of polycarboxylate superplasticizers have become key areas for technological breakthroughs in the industry. Microreactor systems, with their advantages of high mass and heat transfer efficiency, easy control of reaction conditions, and low energy consumption, are gradually replacing traditional batch reactors for superplasticizer synthesis. However, existing systems are mostly integrated structures, lacking targeted functional modular design, making it difficult to adapt to the entire process requirements of polycarboxylate superplasticizer synthesis, including diverse raw material supply, dynamic control of reaction parameters, and accurate product storage, thus restricting its large-scale application and performance improvement.

[0003] Existing equipment for the synthesis of polycarboxylate superplasticizers has many shortcomings in achieving its core functions. Regarding molecular weight control, traditional techniques rely heavily on offline sampling and detection, failing to capture real-time changes in the molecular weight of the reaction system and neglecting the impact of temperature on the results. This leads to lagging control, insufficient precision, and a wide molecular weight distribution in the product. Chain transfer agent storage and supply are often designed for single types and concentrations, unable to flexibly adjust the concentration and dosage according to the reaction progress, limiting the flexibility and accuracy of molecular weight control. Low temperature control precision during raw material mixing and unreasonable flow disturbance structures result in uneven material mixing, prolonging the reaction induction period. The metering and conveying units have poor multi-channel adaptability, narrow flow rate adjustment range, and insufficient corrosion resistance, affecting the stability of the raw material ratio. During the reaction maturation stage, temperature and pressure control lack coordination, and the pressure relief mechanism is insensitive, easily leading to incomplete reactions or fluctuations in product performance. Product filtration uses conventional methods, resulting in poor impurity retention and a lack of automatic backwashing and particle content monitoring functions, making it difficult to guarantee the purity and storage safety of the finished product.

[0004] The shortcomings of the existing technologies mentioned above result in poor product performance consistency, low production efficiency, and insufficient finished product qualification rate during the synthesis of polycarboxylate superplasticizers, making it difficult to meet the stringent requirements of modern engineering for high-performance superplasticizers. Furthermore, the integrated system design makes equipment maintenance difficult and lacks versatility, preventing the replacement and upgrading of functional modules according to different synthesis process requirements, thus increasing production costs and the difficulty of technological iteration. Therefore, developing a modular microreactor system with accurate raw material supply, uniform and efficient mixing, real-time molecular weight control, stable reaction maturation, and safe product purification and storage is of great significance for solving the pain points of existing technologies, improving the level of polycarboxylate superplasticizer synthesis technology, ensuring the quality of engineering construction, and promoting technological upgrading in the industry. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a modular microreactor system for the synthesis of polycarboxylate superplasticizers. This system features a multi-chamber and multi-channel design for raw material supply, ensuring stable material supply and flexible proportioning; molecular weight control integrates dielectric detection functions for real-time monitoring and dynamic adjustment; efficient temperature and pressure control is used for reaction maturation to guarantee product quality and production continuity; product storage combines efficient filtration and intelligent monitoring; and the modular design of the system enhances its versatility and scalability.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a modular microreaction system for the synthesis of polycarboxylate superplasticizer, the system comprising the following components: a raw material feeding module, a raw material mixing module, a molecular weight control module, a reaction maturation module, and a product storage module; The raw material supply module includes a liquid storage unit and a metering and conveying unit. The liquid storage unit is used to store monomer mixture, initiator solution, and chain transfer agent solution. The metering and conveying unit is used to convey the materials in the liquid storage unit to the raw material mixing module according to preset parameters. The preset parameters include the total amount and proportion of each material, flow rate and time program parameters, triggering and safety parameters. The raw material mixing module receives the conveyed materials, mixes the materials through a temperature control structure and a turbulence structure, and monitors the uniformity of material mixing. The molecular weight control module includes a dielectric detection unit, a decision unit, and a replenishment unit. The dielectric detection unit uses a built-in dielectric spectrum signal feature extraction algorithm to collect the dielectric signal of the reaction system and extract feature parameters. The decision unit uses a built-in dielectric relaxation-temperature correction molecular weight inversion algorithm to calculate the weight-average molecular weight of the polycarboxylate superplasticizer in the reaction system to determine the amount of chain transfer agent to be added and generates control commands. The replenishment unit adds chain transfer agent according to the control commands, and the reaction solution is obtained after the control is completed. The reaction maturation module receives the reaction solution from the molecular weight control module, controls the reaction temperature and residence time using a constant temperature structure, monitors the degree of reaction and implements pressure control, and after the reaction reaches the target, it delivers the target reaction solution to the product storage module. The product storage module receives the qualified reaction solution, filters it to remove impurities, stores the purified finished product, and monitors the particulate matter content and storage liquid level of the finished product.

[0007] Furthermore, the chain transfer agent storage section of the liquid storage unit in the raw material supply module adopts a multi-chamber integrated storage tank, including three independent sealed liquid storage chambers, which store different types of chain transfer agent aqueous solutions respectively. The chain transfer agent concentration gradient corresponding to each liquid storage chamber is low concentration 3% to 5%, medium concentration 10% to 15%, and high concentration 20% to 25%. Each liquid storage chamber is equipped with an independent liquid outlet pipeline and control valve.

[0008] Furthermore, the metering and conveying unit in the raw material supply module adopts a multi-channel metering pump. The metering pump is equipped with three independent conveying channels that are respectively connected to each chamber of the liquid storage unit. The part of the pump body that comes into contact with the material is made of corrosion-resistant material. The flow rate adjustment range is 0.1 to 5 ml per minute. The ratio of monomer mixture to initiator solution is adjusted from 10:1 to 20:1.

[0009] Furthermore, the temperature control structure in the raw material mixing module is a jacketed temperature control structure, which controls the temperature through a circulating water bath. The temperature control setting range is 55℃ to 65℃. The turbulence structure consists of spiral turbulence vanes evenly arranged in the channel with an angle of 45°. Adjacent turbulence vanes are arranged in an alternating pattern. The material residence time can be controlled within 1 to 3 minutes by adjusting the flow rate of the metering and conveying unit of the raw material feeding module.

[0010] Furthermore, the dielectric detection unit of the molecular weight control module adopts a flat plate electrode, the sampling frequency of the dielectric signal acquisition device is set to 1 time per second, the built-in noise reduction module extracts characteristic parameters such as peak dielectric constant, dielectric relaxation time, and half width at half maximum of dielectric loss factor, and the data transmission interface is RS485 with a transmission rate of 9600bps.

[0011] Furthermore, the calculation formula for the dielectric spectral signal feature extraction algorithm of the molecular weight regulation module is as follows: ,in, This is the core raw signal acquired by the dielectric detection unit; The angular frequency of the alternating electric field; The real-time temperature of the polycarboxylate superplasticizer reaction system; It is the high-frequency limiting dielectric constant; The number of relaxation processes; Let be the relaxation strength of the i-th relaxation process; The imaginary unit; Let be the characteristic relaxation time of the i-th relaxation process; Let be the relaxation widening parameter for the i-th relaxation process; The DC conductivity of the reaction system; It is the vacuum dielectric constant; it effectively integrates the dielectric signal and temperature correlation information of the polycarboxylate superplasticizer reaction system, and eliminates the interference of temperature fluctuations on the dielectric signal by systematically capturing the dielectric relaxation characteristics during the reaction process. This ensures that the extracted feature information truly reflects the correlation between molecular interactions and polymerization process within the reaction system, providing support for the decision-making unit to accurately determine the amount of chain transfer agent to be added and to achieve dynamic control of the molecular weight of the polycarboxylate superplasticizer.

[0012] Furthermore, the calculation formula for the dielectric relaxation-temperature-corrected molecular weight inversion algorithm of the molecular weight regulation module is as follows: ,in, The weight-average molecular weight of polycarboxylate superplasticizer; These are the characteristic constants of the polycarboxylate superplasticizer reaction system; The characteristic relaxation time; The activation energy for the molecular chain movement of polycarboxylate superplasticizer; It is the ideal gas constant; The real-time temperature of the polycarboxylate superplasticizer reaction system; The reference temperature for the polycarboxylate superplasticizer reaction system; It is a molecular weight-relaxation time correlation index; it realizes the synergistic correlation calculation of dielectric relaxation characteristics and temperature factors of the reaction system, eliminates the interference of temperature fluctuations on the molecular weight inversion process, accurately inverts the weight-average molecular weight of polycarboxylate superplasticizer, and provides a basis for the decision unit to determine the amount of chain transfer agent to be added and generate control commands.

[0013] Furthermore, the process of the replenishment unit in the molecular weight control module replenishing the chain transfer agent according to the control command is as follows: after receiving the control command from the decision unit, the replenishment unit starts the built-in metering pump and delivers the chain transfer agent solution to the reaction system at an adjustable flow rate of 0.5 to 5 mL / min as set by the command. At the same time, the dielectric signal of the reaction system is collected and fed back to the decision unit. When the weight-average molecular weight of the system is detected to be within ±2% of the preset threshold q, the metering pump stops running. After the reaction system is stirred and mixed at a constant temperature for 10 to 15 minutes, the molecular weight control is completed and the reaction solution is obtained.

[0014] Furthermore, the constant temperature structure in the reaction maturation module is a double-layer jacketed temperature control structure, with an inner layer being a heat-conducting oil chamber and an outer layer being a heat-insulating layer. Temperature is controlled by a circulating oil bath, with the maturation temperature set at 65°C. The material residence time can be adjusted within 5 to 8 minutes. The viscosity of the reaction liquid is monitored at the end of the reactor, and a pressure sensor is installed at the top. When the pressure in the channel exceeds 0.3 MPa, the pressure relief valve is automatically opened.

[0015] Furthermore, the product storage module employs a cross-flow filtration structure to filter and trap impurities. The filter membrane has a pore size of 0.22 micrometers, and pressure sensors are installed at the filter inlet and outlet. When the filtration pressure difference exceeds 0.1 MPa, the backwashing program is automatically initiated. The backwashing flow rate is 10 ml per minute. The particle content in the finished liquid is monitored at the outlet of the filter structure. The storage unit has a built-in stirrer with an adjustable speed range of 30 to 50 revolutions per minute. It also has a built-in level gauge. When the liquid level reaches 90% of the tank volume, an early warning is automatically issued, and a pause command is sent to the raw material feeding module.

[0016] Compared with existing technologies, this modular microreaction system for the synthesis of polycarboxylate superplasticizers has the following advantages: I. This invention modularizes the entire synthesis process of polycarboxylate superplasticizers, independently setting up and constructing a collaborative linkage mechanism for functions such as raw material supply, mixing, molecular weight control, reaction maturation, and product storage, achieving accurate control and efficient connection of each link. The raw material supply link adopts a multi-chamber storage and multi-channel conveying design to meet the stable supply and flexible proportion of multiple materials. Combined with a targeted temperature control structure and turbulence design, it enhances the uniformity and efficiency of material mixing, creating optimal initial conditions for subsequent reactions. The molecular weight control link integrates dielectric detection, intelligent decision-making, and accurate replenishment functions. Through a dedicated algorithm, it extracts characteristic parameters of the reaction system and corrects for the influence of temperature, realizing real-time monitoring and dynamic adjustment of molecular weight, effectively optimizing the molecular weight distribution of the product, improving the consistency of product performance, solving the problems of lagging control and insufficient precision in traditional technologies, while simplifying the control process, reducing errors caused by human intervention, and promoting the intelligent upgrade of the synthesis process.

[0017] II. This invention optimizes the structural design of the reaction maturation and product storage modules to construct a stable and reliable subsequent processing system, further ensuring product quality and production continuity. The reaction maturation stage employs a highly efficient constant temperature structure and pressure control mechanism to ensure the reaction proceeds fully under suitable conditions, avoiding product performance fluctuations caused by temperature fluctuations or abnormal pressure, and improving reaction conversion rate and product purity. The product storage stage combines high-efficiency filtration and intelligent monitoring functions to effectively intercept impurities generated during the reaction process, monitor the purity of the finished product in real time, and reduce the risk of filter clogging by combining automatic backwashing and liquid level warning mechanisms, ensuring the safety and continuity of the storage process and reducing manual maintenance costs. The overall modular design enhances the system's versatility and scalability, enabling flexible adaptation to different synthesis process requirements and providing technical support for the large-scale, high-quality production of polycarboxylate superplasticizers.

[0018] Other advantages, objectives and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be learned from the practice of the invention. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0020] Figure 1 A block diagram of the modular microreaction system for the synthesis of polycarboxylate superplasticizers; Figure 2 A flowchart of a modular microreaction system for the synthesis of polycarboxylate superplasticizers; Figure 3 This is a schematic diagram of data transmission for the molecular weight control module of a modular microreaction system used in the synthesis of polycarboxylate superplasticizers. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0022] In the description of this invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Furthermore, the technical features involved in the different embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0024] Example 1 The raw material supply module's storage unit stores the monomer mixture, initiator solution, and chain transfer agent solution separately. A medium-concentration chamber in a multi-chamber integrated tank is used, with a concentration of 10% to 15%. Three independent, sealed storage chambers, along with dedicated outlet pipelines and control valves, prevent cross-contamination between different chain transfer agents. The metering and delivery unit employs a multi-channel metering pump. Three independent delivery channels accurately connect to each chamber of the storage unit. The pump body's material-contacting parts are made of corrosion-resistant material, resisting material corrosion and extending equipment life. The monomer mixture to initiator solution delivery ratio is adjusted to 15:1, and the overall delivery flow rate is set to 2 ml / min, ensuring a stable and continuous delivery of the three materials to the raw material mixing module in a preset ratio, laying a uniform material foundation for subsequent reactions.

[0025] After receiving the materials, the raw material mixing module activates a circulating water bath via a jacketed temperature control structure to maintain the mixing system temperature at 60℃. This stable temperature environment ensures consistent initial reaction conditions. Simultaneously, 45° spiral baffles are evenly distributed within the channel, with adjacent baffles arranged in an alternating pattern. This breaks the material flow inertia and promotes full contact. By maintaining the current flow rate of the metering and conveying unit, the residence time of the materials within the module is controlled to 2 minutes. During this period, the uniformity of material mixing is monitored in real time to prevent localized concentration imbalances from affecting the reaction effect, ensuring that the material mixing reaches the desired reaction state.

[0026] The dielectric detection unit of the molecular weight control module activates the planar electrode to acquire the dielectric signal of the reaction system at a sampling frequency of once per second. The built-in noise reduction module extracts three characteristic parameters: peak dielectric constant, dielectric relaxation time, and dielectric loss factor half-width at half-maximum. Data is transmitted quickly and stably to the decision unit via an RS485 interface at a transmission rate of 9600 bps. The decision unit then uses a dielectric spectrum signal feature extraction algorithm to process the raw signal. The formula is: ,in, This is the core raw signal acquired by the dielectric detection unit; The angular frequency of the alternating electric field; The real-time temperature of the polycarboxylate superplasticizer reaction system; It is the high-frequency limiting dielectric constant; The number of relaxation processes; Let be the relaxation strength of the i-th relaxation process; The imaginary unit; Let be the characteristic relaxation time of the i-th relaxation process; Let be the relaxation widening parameter for the i-th relaxation process; The DC conductivity of the reaction system; The vacuum dielectric constant is used; then, the weight-average molecular weight of the polycarboxylate superplasticizer in the reaction system is accurately calculated using the dielectric relaxation-temperature correction molecular weight inversion algorithm. Based on this, a chain transfer agent replenishment control command is generated, and the formula is: ,in, The weight-average molecular weight of polycarboxylate superplasticizer; These are the characteristic constants of the polycarboxylate superplasticizer reaction system; The characteristic relaxation time; The activation energy for the molecular chain movement of polycarboxylate superplasticizer; It is the ideal gas constant; The real-time temperature of the polycarboxylate superplasticizer reaction system; The reference temperature for the polycarboxylate superplasticizer reaction system; This is the molecular weight-relaxation time correlation index. After receiving the instruction, the replenishment unit starts the built-in metering pump and adds the corresponding concentration of chain transfer agent solution to the reaction system at a flow rate of 3 mL / min. Simultaneously, the dielectric signal of the reaction system is collected and fed back to the decision unit to track the change in molecular weight in real time. When the weight-average molecular weight of the system enters the range of ±2% of the preset threshold, the metering pump stops running. The reaction system is mixed at a constant temperature for 12 minutes to make the molecular weight of the reaction system reach a medium level and be uniformly distributed, thus completing the molecular weight control and obtaining a qualified reaction solution.

[0027] The reaction maturation module receives the molecular weight-controlled reaction liquid and uses a double-jacketed temperature control structure. The inner layer is a heat-conducting oil chamber, and the outer layer is an insulation layer. A circulating oil bath is activated to stabilize the maturation temperature at 65℃, minimizing the impact of temperature fluctuations on the reaction process. By adjusting relevant pipeline parameters, the material residence time is maintained at 6 minutes to ensure a complete reaction. During this period, the viscosity of the reaction liquid is continuously monitored at the end of the reactor to visually assess the degree of reaction. A pressure sensor at the top monitors the pressure inside the chamber in real time. When the pressure exceeds 0.3MPa, the system automatically opens the pressure relief valve to release pressure and prevent safety hazards caused by excessive pressure. Once the reaction reaches the target degree, the reaction liquid is smoothly transported to the product storage module.

[0028] After receiving the qualified reaction solution, the product storage module uses a cross-flow filtration structure to trap impurities. The 0.22-micron pore size of the filter membrane effectively removes tiny impurities, and pressure sensors at the inlet and outlet of the filter monitor the pressure difference in real time. When the filtration pressure difference exceeds 0.1 MPa, the system automatically initiates a backwashing procedure. A backwashing flow rate of 10 ml / min restores the membrane's permeability, ensuring filtration efficiency. The particulate matter content in the finished product solution is simultaneously monitored at the filter outlet to ensure purification effectiveness. The purified product enters the storage unit, where a built-in stirrer continuously agitates at 40 rpm to prevent sedimentation and stratification. A built-in level gauge monitors the storage liquid level in real time. When the liquid level reaches 90% of the tank volume, the system automatically issues a warning signal and sends a pause command to the raw material feeding module to prevent overflow and ensure a safe and orderly storage process.

[0029] This embodiment addresses the industrial synthesis needs of conventional medium molecular weight polycarboxylate superplasticizers. Based on a modular microreactor system, each module operates collaboratively. The raw material supply module utilizes multi-chamber storage tanks and multi-channel metering pumps to achieve accurate and proportioned material delivery without cross-contamination. The raw material mixing module employs jacketed temperature control and a spiral baffle design to ensure uniform mixing and temperature stability. The molecular weight control module, through dielectric detection, a proprietary algorithm, and accurate replenishment, ensures the product reaches the target molecular weight and has a uniform distribution. The reaction maturation module ensures a complete and safe reaction through constant temperature control and pressure protection. The product storage module, through cross-flow filtration, backwashing, and stirring monitoring, guarantees the purity and storage safety of the finished product. Figure 1 As shown.

[0030] Example 2 The raw material supply module's storage units separately store monomer mixtures, initiator solutions, and chain transfer agent solutions. High-concentration chambers in multi-chamber integrated storage tanks are used, with concentrations ranging from 20% to 25%. Each of the three independent, sealed storage chambers is equipped with dedicated outlet pipelines and control valves, allowing for independent use of chain transfer agents of different concentrations and preventing confusion. The metering and delivery unit employs a multi-channel metering pump. Three independent delivery channels accurately connect to each chamber of the storage unit. The pump body's material-contacting parts are made of corrosion-resistant material, resisting material corrosion and extending the equipment's service life. The delivery ratio of monomer mixture to initiator solution is adjusted to 20:1, and the overall delivery flow rate is set at 0.5 ml / min. This slow and stable delivery rhythm allows the materials to fully integrate in subsequent mixing stages, providing suitable material ratios for the synthesis of low molecular weight products.

[0031] The raw material mixing module utilizes a jacketed temperature control structure, maintaining the mixing system temperature at 55℃ via a circulating water bath. This lower temperature environment suppresses side reactions and ensures the directional conduction of the reaction. Strong turbulence is generated using 45° staggered spiral baffles, breaking up material stratification. By maintaining the current flow rate of the metering and conveying unit, the material residence time within the module is controlled to 3 minutes. This sufficient residence time allows for more uniform mixing. Continuous monitoring of the mixing uniformity ensures that the material reaches a molecular-level mixing state, providing a solid foundation for accurate molecular weight control.

[0032] The plate electrode of the dielectric detection unit begins operation, acquiring the dielectric signal of the reaction system at a sampling frequency of once per second. A built-in noise reduction module extracts the peak dielectric constant, dielectric relaxation time, and dielectric loss factor half-width at half-maximum characteristic parameters, transmitting data via an RS485 interface to reduce signal delay. The decision unit first processes the raw signal using a dielectric spectrum signal feature extraction algorithm, then accurately calculates the weight-average molecular weight using a dielectric relaxation-temperature-corrected molecular weight inversion algorithm, accurately determining the chain transfer agent replenishment amount and generating control commands. The metering pump of the replenishment unit adds chain transfer agent solution to the reaction system at a flow rate of 0.5 mL / min. This low-flow replenishment mode avoids over- or under-addition. The dielectric signal is simultaneously acquired and fed back to the decision unit, adjusting the replenishment process in real time. When the weight-average molecular weight reaches within ±2% of the preset threshold, the metering pump stops operating. The reaction system is then stirred and mixed at a constant temperature for 15 minutes to reduce the molecular weight of the reaction system to a low level and narrow distribution, obtaining a reaction solution that meets the molecular weight requirements. Figure 3 As shown.

[0033] The double-jacketed temperature control structure of the reaction maturation module activates the circulating oil bath to stabilize the maturation temperature at 65℃, ensuring efficient reaction at a constant temperature. Material residence time is controlled to 8 minutes via pipeline adjustments, allowing sufficient time for the reaction to complete the conversion. Real-time monitoring of the reaction liquid viscosity at the reactor end accurately controls the reaction endpoint. A pressure sensor at the top continuously monitors the pressure; when the pressure exceeds 0.3MPa, the system automatically opens the pressure relief valve to release pressure, preventing abnormal pressure from affecting product quality. Once the reaction reaches the target, the reaction liquid is smoothly transported to the product storage module.

[0034] The product storage module filters the reaction solution using a cross-flow filtration structure. The 0.22-micron pore size of the filter membrane effectively traps fine impurities, improving the purity of the finished product. Inlet and outlet pressure sensors monitor the filtration pressure difference. When the pressure difference exceeds 0.1 MPa, a backwashing procedure is automatically initiated. The backwashing flow rate of 10 ml / min effectively cleans impurities from the membrane surface, maintaining filtration efficiency. After filtration, the particulate matter content in the finished product is monitored at the outlet to ensure it meets high purity requirements. Qualified finished products enter the storage unit, where a built-in stirrer slowly agitates the product at 30 rpm. This prevents sedimentation and avoids damaging the product structure due to excessive agitation. A level gauge monitors the liquid level in real time. When the level reaches 90% of the tank volume, an automatic warning is issued, and a pause command is sent to the raw material feeding module to ensure storage safety and maintain stable finished product quality.

[0035] This embodiment focuses on the synthesis of high-purity, low-molecular-weight polycarboxylate superplasticizers, fully leveraging the precise control advantages of a modular microreactor system. The raw material feeding module uses a high-concentration chain transfer agent, coupled with low-flow-rate delivery, laying the foundation for low-molecular-weight synthesis. The raw material mixing module suppresses side reactions and promotes deep mixing of materials through low-temperature control and extended residence time. The molecular weight control module achieves accurate molecular weight control through high-frequency detection, accurate algorithms, and low-flow-rate replenishment. The reaction maturation module ensures complete reaction through constant temperature and sufficient residence time. The product storage module improves the purity of the finished product and maintains stable quality through deep filtration, gentle stirring, and continuous monitoring. Figure 2 As shown.

[0036] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A modular microreaction system for the synthesis of polycarboxylate superplasticizers, characterized in that, The system comprises the following components: a raw material feeding module, a raw material mixing module, a molecular weight control module, a reaction maturation module, and a product storage module; The raw material supply module includes a liquid storage unit and a metering and conveying unit. The liquid storage unit is used to store monomer mixture, initiator solution and chain transfer agent solution. The metering and conveying unit is used to convey the materials in the liquid storage unit to the raw material mixing module according to preset parameters. The raw material mixing module receives the conveyed materials, mixes the materials through a temperature control structure and a turbulence structure, and monitors the uniformity of material mixing. The molecular weight control module includes a dielectric detection unit, a decision unit, and a replenishment unit. The dielectric detection unit uses a built-in dielectric spectrum signal feature extraction algorithm to collect the dielectric signal of the reaction system and extract feature parameters. The decision unit uses a built-in dielectric relaxation-temperature correction molecular weight inversion algorithm to calculate the weight-average molecular weight of the polycarboxylate superplasticizer in the reaction system to determine the amount of chain transfer agent to be added and generates control commands. The replenishment unit adds chain transfer agent according to the control commands, and the reaction solution is obtained after the control is completed. The reaction maturation module receives the reaction solution from the molecular weight control module, controls the reaction temperature and residence time using a constant temperature structure, monitors the degree of reaction and implements pressure control, and after the reaction reaches the target, it delivers the target reaction solution to the product storage module. The product storage module receives the qualified reaction solution, filters it to remove impurities, stores the purified finished product, and monitors the particulate matter content and storage liquid level of the finished product.

2. The modular microreaction system for the synthesis of polycarboxylate superplasticizer according to claim 1, characterized in that, The chain transfer agent storage section of the liquid storage unit in the raw material supply module adopts a multi-chamber integrated storage tank, including three independent sealed liquid storage chambers, which store different types of chain transfer agent aqueous solutions respectively. The chain transfer agent concentration gradient corresponding to each liquid storage chamber is low concentration 3% to 5%, medium concentration 10% to 15%, and high concentration 20% to 25%. Each liquid storage chamber is equipped with an independent liquid outlet pipeline and control valve.

3. The modular microreaction system for the synthesis of polycarboxylate superplasticizer according to claim 1, characterized in that, The metering and conveying unit in the raw material supply module adopts a multi-channel metering pump. The metering pump is equipped with three independent conveying channels that are respectively connected to each chamber of the liquid storage unit. The part of the pump body that comes into contact with the material is made of corrosion-resistant material. The flow rate adjustment range is 0.1 to 5 ml per minute. The ratio of monomer mixture to initiator solution is adjusted from 10:1 to 20:

1.

4. The modular microreaction system for the synthesis of polycarboxylate superplasticizer according to claim 1, characterized in that, The temperature control structure in the raw material mixing module is a jacketed temperature control structure, which controls the temperature through a circulating water bath. The temperature control setting range is 55℃ to 65℃. The turbulence structure consists of spiral turbulence vanes evenly arranged in the channel. The angle of the turbulence vanes is 45° and the adjacent turbulence vanes are arranged in an alternating manner. The material residence time can be controlled within 1 to 3 minutes by adjusting the flow rate of the metering and conveying unit of the raw material feeding module.

5. A modular microreaction system for the synthesis of polycarboxylate superplasticizers according to claim 1, characterized in that, The dielectric detection unit of the molecular weight control module adopts a flat plate electrode. The sampling frequency of the dielectric signal acquisition device is set to 1 time per second. The built-in noise reduction module extracts characteristic parameters such as peak dielectric constant, dielectric relaxation time, and half width at half maximum of dielectric loss factor. The data transmission interface is RS485 with a transmission rate of 9600bps.

6. The modular microreaction system for the synthesis of polycarboxylate superplasticizer according to claim 1, characterized in that, The calculation formula for the dielectric spectral signal feature extraction algorithm of the molecular weight regulation module is as follows: ,in, This is the core raw signal acquired by the dielectric detection unit; The angular frequency of the alternating electric field; The real-time temperature of the polycarboxylate superplasticizer reaction system; It is the high-frequency limiting dielectric constant; The number of relaxation processes; Let be the relaxation strength of the i-th relaxation process; The imaginary unit; Let be the characteristic relaxation time of the i-th relaxation process; Let be the relaxation widening parameter for the i-th relaxation process; The DC conductivity of the reaction system; is the vacuum permittivity.

7. A modular microreaction system for the synthesis of polycarboxylate superplasticizers according to claim 1, characterized in that, The calculation formula for the dielectric relaxation-temperature-corrected molecular weight inversion algorithm of the molecular weight regulation module is as follows: ,in, The weight-average molecular weight of polycarboxylate superplasticizer; These are the characteristic constants of the polycarboxylate superplasticizer reaction system; The characteristic relaxation time; The activation energy for the molecular chain movement of polycarboxylate superplasticizer; It is the ideal gas constant; The real-time temperature of the polycarboxylate superplasticizer reaction system; The reference temperature for the polycarboxylate superplasticizer reaction system; This is the molecular weight-relaxation time correlation index.

8. A modular microreaction system for the synthesis of polycarboxylate superplasticizers according to claim 1, characterized in that, The process of adding chain transfer agent in the molecular weight control module according to the control command is as follows: After receiving the control command from the decision unit, the addition unit starts the built-in metering pump and delivers the chain transfer agent solution to the reaction system at an adjustable flow rate of 0.5 to 5 mL / min as set by the command. At the same time, the dielectric signal of the reaction system is collected and fed back to the decision unit. When the weight-average molecular weight of the system reaches within ±2% of the preset threshold q, the metering pump stops running. After the reaction system is stirred and mixed at a constant temperature for 10 to 15 minutes, the molecular weight control is completed and the reaction solution is obtained.

9. A modular microreaction system for the synthesis of polycarboxylate superplasticizers according to claim 1, characterized in that, The constant temperature structure in the reaction maturation module is a double-layer jacketed temperature control structure. The inner layer is a heat-conducting oil chamber, and the outer layer is a heat-insulating layer. Temperature is controlled by a circulating oil bath. The maturation temperature is set at 65℃, and the material residence time can be adjusted within 5 to 8 minutes. The viscosity of the reaction liquid is monitored at the end of the reactor, and a pressure sensor is installed at the top. When the pressure in the channel exceeds 0.3MPa, the pressure relief valve is automatically opened.

10. A modular microreaction system for the synthesis of polycarboxylate superplasticizers according to claim 1, characterized in that, The product storage module uses a cross-flow filtration structure to filter out impurities. The filter membrane has a pore size of 0.22 micrometers. Pressure sensors are installed at the filter inlet and outlet. When the filtration pressure difference exceeds 0.1 MPa, the backwashing program is automatically started. The backwashing flow rate is 10 ml per minute. The particle content in the finished liquid is monitored at the outlet of the filter structure. The storage unit has a built-in stirrer with an adjustable speed range of 30 to 50 revolutions per minute. It also has a built-in level gauge. When the liquid level reaches 90% of the tank volume, an early warning is automatically issued and a pause command is sent to the raw material feeding module.

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