A system and method for continuously producing organic carboxylate salt nucleating agents in a fully aqueous system

Abstract

The application discloses a system and a method for continuously preparing organic carboxylic acid salt nucleating agents in a full water system, and the system comprises a feeding unit, a reaction unit and a spray drying unit connected in sequence; the feeding unit comprises first and second feeding pumps; the reaction unit comprises a continuous flow stirring reactor; the first and second feeding pumps are connected with feeding ports of the continuous flow stirring reactor in parallel; the spray drying unit comprises a spray dryer; and a discharge port of the continuous flow stirring reactor is connected with a feeding port of the spray dryer. The cascade continuous flow reaction system is constructed by selecting the continuous flow stirring reactor and the spray dryer, so that the organic carboxylic acid salt nucleating agents are efficiently and greenly synthesized in the full water system, the obtained organic carboxylic acid salt nucleating agents have the characteristics of more uniform particle size distribution, good dispersibility, smaller variation coefficient and high yield, and have wide industrialization prospects.

Description

Technical Field

[0001] This invention relates to the field of organic carboxylate nucleating agent technology, and more specifically, to a system and method for preparing organic carboxylate nucleating agents in a continuous flow in an all-aqueous system. Background Technology

[0002] Nucleating agents are polymer modifying additives widely used in incompletely crystalline plastics such as polyethylene and polypropylene. They can be classified into inorganic nucleating agents, organic nucleating agents, polymeric nucleating agents, and β-crystalline nucleating agents. Organic carboxylic acid metal salt nucleating agents exhibit outstanding thermal stability, strong nucleating ability, are non-toxic, odorless, and have good compatibility with polymer resins, significantly improving the transparency and surface gloss of finished products. The performance of nucleating agents is affected by the coefficient of variation. The smaller the coefficient of variation, the better the nucleating performance.

[0003] Traditional methods for preparing nucleating agents involve batch reactions using a batch reactor. European patent EP1209190 further reduces the particle size of the synthesized organophosphate nucleating agent using a combination of ball milling and jet milling, resulting in complex equipment. Chinese patent CN102827205B uses organic solvents to aid dissolution after synthesizing the organophosphate nucleating agent in a reactor, requiring high-temperature reaction and final cooling to precipitate the solid, leading to high energy consumption. Chinese patent CN104559141B adds a light stabilizer as an oil phase to aid dispersion and improve aging resistance; Chinese patent CN109401290A uses the mutual barrier effect of graphene and sodium benzoate to inhibit aggregation. These methods of adding additives are complex and costly. CN111978192A uses organic solvents to dissolve the raw materials, raising environmental concerns. CN109401060B uses an antisolvent method to precipitate nucleating agent solution. This method requires the selection of a suitable antisolvent for different nucleating agents, and the antisolvent may carry away some of the target product, resulting in a decrease in yield.

[0004] In summary, existing synthesis methods using batch reactors have significant drawbacks, such as batch-to-batch product variability, complex operation, high cost and energy consumption, and low yield. These problems are extremely detrimental to the later application of nucleating agents. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned defects in the prior art and provide a system and method for preparing organic carboxylate nucleating agents in a continuous flow in an all-aqueous system. By selecting a continuous flow stirred reactor and a spray dryer to construct a cascaded continuous flow reaction system, efficient and green continuous flow synthesis of organic carboxylate nucleating agents is achieved in an all-aqueous system. The resulting organic carboxylate nucleating agents have more uniform particle size distribution, better dispersibility, smaller coefficient of variation, and higher yield, and have broad industrial application prospects.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A system for the continuous flow preparation of organic carboxylate nucleating agents in an all-aqueous system, the system comprising a feeding unit, a reaction unit, and a spray drying unit connected in sequence; the feeding unit comprising a first feed pump and a second feed pump; the reaction unit comprising a continuous flow stirred reactor; the first feed pump and the second feed pump being connected in parallel to the inlet of the continuous flow stirred reactor; the spray drying unit comprising a spray dryer; the outlet of the continuous flow stirred reactor being connected to the inlet of the spray dryer.

[0008] This invention also discloses a method for preparing organic carboxylate nucleating agents in a continuous flow process in an all-aqueous system, using the above-described system, specifically including the following steps:

[0009] The first reactant and the second reactant are continuously fed into a continuous flow stirred reactor via a first feed pump and a second feed pump, respectively, to react and obtain the reaction products.

[0010] The reaction product is continuously fed through the outlet of a continuous flow stirred reactor to the spray dryer for spray drying to obtain the organic carboxylate nucleating agent.

[0011] Implementing the embodiments of the present invention will have the following beneficial effects:

[0012] 1. This invention provides a system and method for the continuous flow preparation of organic carboxylate nucleating agents in an all-aqueous system. By selecting a continuous flow stirred reactor (CSTR) and a spray dryer to construct a cascaded continuous flow reaction system, efficient and green continuous flow synthesis of organic carboxylate nucleating agents is achieved in an all-aqueous system. The resulting organic carboxylate nucleating agents have more uniform particle size distribution, better dispersibility, smaller coefficient of variation, and higher yield, and have broad industrial application prospects.

[0013] 2. This invention cascades a CSTR (Continuous Stirring Array) with a spray dryer, enabling continuous flow synthesis of organic carboxylate nucleating agents in an all-aqueous system. Firstly, for reactions generating organic carboxylate nucleating agents in an all-aqueous system, a CSTR with a small geometric volume and low clogging tendency is selected. Through continuous flow feeding, the reactant aqueous solution undergoes continuous synthesis within the CSTR. Simultaneously, the CSTR device has a simple structure and is easy to manufacture; structurally, it is merely a small, sealed stirring device that can be adjusted appropriately according to the reaction environment. Subsequently, the slurry obtained from the continuous reaction in the CSTR is continuously spray-dried, ultimately yielding an organic carboxylate nucleating agent with a low coefficient of variation. This achieves continuous production of organic carboxylate nucleating agents, resulting in low cost, no odor, no discoloration, and good dispersibility.

[0014] 3. This invention rationally transfers the synthesis method in a batch reactor to a cascaded continuous flow reaction system, which can better achieve precise control of reaction conditions, such as temperature, pressure, and material flow rate. It ensures that the reaction module is compatible with and easy to adjust process parameters, enabling continuous and rapid mixing of reactants in the reactor, greatly improving reaction efficiency and reaction time. It can provide a more uniform reaction environment, thereby reducing the impact of fluctuations in reaction conditions on product properties, helping to reduce local concentration and temperature inhomogeneity, thus reducing the coefficient of variation of nucleating agents, resulting in more uniform product quality and reduced batch-to-batch differences.

[0015] 4. This invention eliminates the need for organic solvents during the reaction process, eliminates the need for pulping of raw materials, and eliminates the need for post-processing such as grinding of products, thus reducing operational complexity. Furthermore, the steam generated during spray drying can be recovered and recycled, reducing pollution and enabling the green preparation of organic carboxylate nucleating agents.

[0016] 5. The cascade device of the present invention is detachable, easy to clean, simple to assemble, occupies a small area, has low cost, and can be industrialized for large-scale production. Attached Figure Description

[0017] Figure 1 This is a system flow diagram for the continuous flow preparation of organic carboxylate nucleating agents in an all-water system according to an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the continuous flow stirred reactor structure according to an embodiment of the present invention.

[0019] The components include: 1. Feeding unit; 11. First feed pump; 12. Second feed pump; 2. Continuous flow stirred reactor; 21. Base; 22. Sealing plate; 23. Transparent corrosion-resistant plate; 24. Cover plate; 211. Liquid pool; 212. First inlet passage; 213. Second inlet passage; 214. Outlet passage; 241. First through hole; 221. Second through hole; 242. Engaging groove; 3. Spray dryer. Detailed Implementation

[0020] The present invention will be further described below with reference to specific embodiments, but this does not limit the present invention in any way.

[0021] This invention first provides a system for the continuous flow preparation of organic carboxylate nucleating agents in an all-aqueous system, such as... Figures 1-2 As shown, Figure 1 This is a system flow diagram of the continuous flow preparation of organic carboxylate nucleating agents in an all-aqueous system according to an embodiment of the present invention. Figure 2The schematic diagram of the continuous flow stirred reactor structure according to an embodiment of the present invention shows that the system includes a feeding unit 1, a reaction unit, and a spray drying unit connected in sequence; the feeding unit 1 includes a first feed pump 11 and a second feed pump 12; the reaction unit includes a continuous flow stirred reactor 2; the first feed pump 11 and the second feed pump 12 are connected in parallel to the feed inlet of the continuous flow stirred reactor 2; the spray drying unit includes a spray dryer 3; the discharge outlet of the continuous flow stirred reactor 2 is connected to the feed inlet of the spray dryer 3.

[0022] Specifically, the system for organic carboxylate nucleating agents provided by this invention firstly employs a multi-channel continuous pumping and immediate mixing feeding method, which allows for better control of the feeding amount and conditions. Secondly, a continuous flow stirred reactor 2 with a small geometric volume and low clogging tendency is selected, and continuous flow feeding enables continuous synthesis of the reactant aqueous solution in the continuous flow stirred reactor 2; simultaneously, the continuous flow stirred reactor 2 has a simple structure and is easy to manufacture. Subsequently, the slurry obtained from the continuous reaction is continuously fed into a spray dryer 3 for spray drying, ultimately yielding an organic carboxylate nucleating agent with more uniform particle size distribution, a smaller coefficient of variation, and a high yield. This achieves efficient and green continuous flow synthesis of organic carboxylate nucleating agents in an all-aqueous system, with low cost, no odor, no discoloration, and good dispersibility.

[0023] In one specific embodiment, the particle size variation coefficient of the organic carboxylate nucleating agent is 10% to 50%.

[0024] In one specific embodiment, the drying gas flow rate of the spray dryer 3 is 0 mL·min. -1 ~100.00 mL·min -1 The inlet temperature of spray dryer 3 is 10℃~300℃; the spray gas flow rate of spray dryer 3 is 0mL·min. -1 ~10.00 mL·min -1 The outlet temperature is 20℃~300℃.

[0025] In one specific embodiment, the flow rates of both the first feed pump 11 and the second feed pump 12 are 0.01 mL·min. -1 ~20mL·min -1 .

[0026] In one specific embodiment, the continuous flow stirred reactor 2 includes a base 21 and a cover plate 24 disposed opposite to each other, a sealing plate 22 disposed between the base 21 and the cover plate 24, and a transparent corrosion-resistant plate 23 disposed between the sealing plate 22 and the cover plate 24. The base 21 includes a liquid pool 211, a magnetic element placed inside the liquid pool 211, and a first inlet passage 212, a second inlet passage 213, and an outlet passage 214 connected to the liquid pool 211. The first inlet passage 212 is connected to the outlet of the first feed pump 11. The second inlet passage 213 is connected to the outlet of the second feed pump 12. The outlet passage 214 is connected to the inlet of the spray dryer 3. The cover plate 24 and the sealing plate 22 are respectively provided with a first through hole 241 and a second through hole 221. The diameters of the first through hole 241 and the second through hole 221 are the same as the diameter of the liquid pool 211, and the diameters of the first through hole 241 and the second through hole 221 are smaller than the diameter of the transparent corrosion-resistant plate 23.

[0027] In one specific embodiment, the angle between the first inlet passage 212 and the second inlet passage 213 is 15° to 180°, and the angles between the first inlet passage 212 and the outlet passage 214, as well as the angles between the second inlet passage 213 and the outlet passage 214, are both 90° to 172.5°. Specifically, setting the inlet passages with angles within this range allows the reactants to achieve high-speed collision mixing within the liquid pool 211.

[0028] In one specific embodiment, the liquid pool 211 is a rounded-corner liquid pool. Specifically, the connection points between the liquid pool 211 and the first inlet passage 212, the second inlet passage 213, and the outlet passage 214 are set to rounded corners, which can minimize dead zones, improve mixing effect, prevent the generated organic carboxylate nucleating agent from depositing and clogging the passages, and accelerate the flow of reactants.

[0029] In one specific embodiment, the ratio of the diameter to the height of the liquid pool 211 is 1:(0.5~10); the diameter of the liquid pool 211 is 5mm~200mm; and the height of the liquid pool 211 is 5mm~200mm. Specifically, by reasonably selecting the ratio of the diameter to the height of the liquid pool 211 through multiple experiments, a better mixing effect, stability, and controllability can be ensured.

[0030] In one specific embodiment, the inner diameter of the outlet passage 214 is 2mm to 100mm.

[0031] In one specific embodiment, the base 21, cover plate 24 and sealing plate 22 are detachably connected by bolts.

[0032] In one specific embodiment, the cover plate 24 is provided with a locking groove 242 adapted to the transparent corrosion-resistant plate 23; the transparent corrosion-resistant plate 23 is correspondingly embedded in the locking groove 242.

[0033] In one specific embodiment, the transparent corrosion-resistant plate 23 can be a convex transparent corrosion-resistant plate 23. Specifically, the convex surface of the convex transparent corrosion-resistant plate 23 is disposed facing the cover plate 24, and the bottom surface of the convex transparent corrosion-resistant plate 23 is correspondingly embedded in the engaging groove 242 of the cover plate 24. Moreover, the diameter of the first through hole 241 of the cover plate 24 matches the diameter of the convex surface, ensuring good sealing while the convex surface is more conducive to observing the reaction inside the liquid pool 211.

[0034] In one specific embodiment, the transparent corrosion-resistant plate 23 is made of either glass or transparent plastic. Preferably, the transparent corrosion-resistant plate 23 is made of soda-lime glass.

[0035] In one specific embodiment, the sealing plate 22 is made of polytetrafluoroethylene.

[0036] In one specific embodiment, the rotational speed of the continuous flow stirred reactor 2 is 300 rpm to 1200 rpm.

[0037] In one specific embodiment, the feeding unit, reaction unit, and spray drying unit are connected by pipes and connectors. How to select pipes and connectors during connection is an existing technology in the relevant technical field. Those skilled in the relevant technical field are capable of acquiring this technology and applying it to the connection between the feeding unit, reaction unit, and spray drying unit. This is an essential skill for those skilled in the relevant technical field. Therefore, this invention will not describe this step in detail.

[0038] The working principle of the system of this invention is as follows: First, the system is assembled. The first feed pump 11 is connected to the first inlet passage 212 of the continuous flow stirred reactor 2 through a pipeline, and the second feed pump 12 is connected to the second inlet passage 213 of the continuous flow stirred reactor 2 through a pipeline. The outlet passage 214 of the continuous flow stirred reactor 2 is connected to the feed inlet of the spray dryer 3. When the system is working, a preset proportion of first reactant and second reactant are first added to the first feed pump 11 and the second feed pump 12. The first feed pump 11 and the second feed pump 12 are turned on, and the preset proportion of reactant continuously enters the liquid tank 211 from the inlet passage of the continuous flow stirred reactor 2 through the feed pumps to react. The retention time is controlled so that the reaction product continuously enters the spray dryer 3 from the outlet passage 214 for spray drying, thereby achieving continuous discharge.

[0039] Specifically, the continuous flow synthesis system for organic carboxylate nucleating agents of the present invention utilizes a cascaded continuous flow reaction system constructed by selecting a continuous flow stirred reactor 2 and a spray dryer 3. This achieves efficient and environmentally friendly continuous flow synthesis of organic carboxylate nucleating agents in an all-aqueous system, resulting in organic carboxylate nucleating agents with more uniform particle size distribution, better dispersibility, lower coefficient of variation, and higher yield, thus possessing broad industrialization prospects. Furthermore, the cascaded device of the present invention is detachable, easy to clean, simple to assemble, occupies a small area, and has low cost, enabling large-scale industrial production.

[0040] Furthermore, the present invention also provides a method for preparing organic carboxylate nucleating agents in a continuous flow process in an all-aqueous system, using the system as described in any embodiment of the present invention, specifically including the following steps:

[0041] (1) Dissolve carboxylic anhydride in an aqueous sodium hydroxide solution to obtain the first reactant; dissolve the metal chloride in water to obtain the second reactant.

[0042] (2) The first reactant and the second reactant are continuously fed into the continuous flow stirred reactor 2 by the first feed pump 11 and the second feed pump 12 respectively to react and obtain the reaction product.

[0043] (3) The reaction product is continuously conveyed to the spray dryer 3 through the outlet of the continuous flow stirred reactor 2 for spray drying to obtain an organic carboxylate nucleating agent.

[0044] In one specific embodiment, the carboxylic anhydride includes one or more of malonic anhydride, glutaric anhydride, adipic anhydride, pimelic anhydride, octanoic anhydride, benzoic anhydride, and cis-1,2-cyclohexanedicarboxylic anhydride.

[0045] In one specific embodiment, the metal chloride includes one or more of sodium chloride, calcium chloride, cadmium chloride, and aluminum chloride.

[0046] In one specific embodiment, the concentration of carboxylic anhydride in the first reactant is 0.1 mol·L⁻¹. -1 ~5.0 mol·L -1 The concentration of the metal chloride in the second reactant is 0.1 mol·L⁻¹. -1 ~5.0 mol·L -1 .

[0047] Specifically, this invention rationally transfers the synthesis method from a batch reactor to a cascaded continuous flow reaction system. It can be used for the continuous flow synthesis of organic carboxylate nucleating agents in an all-aqueous system, allowing for better precise control of reaction conditions such as temperature, pressure, and material flow rate. This ensures the reaction module is compatible with and easily adjustable process parameters, enabling continuous and rapid mixing of reactants within the reactor, significantly improving reaction efficiency and time. It provides a more uniform reaction environment, reducing the impact of fluctuations in reaction conditions on product properties, and minimizing localized concentration and temperature inhomogeneities, thereby lowering the coefficient of variation of the nucleating agent. The resulting product quality is more uniform and batch-to-batch variations are reduced. Furthermore, this invention eliminates the need for organic solvents, raw material pulping, and post-processing such as grinding of the product, reducing operational complexity. The spray-drying steam can be recovered and recycled, reducing pollution and enabling the green preparation of organic carboxylate nucleating agents.

[0048] The following are specific embodiments.

[0049] Example 1

[0050] This embodiment uses the production of the nucleating agent calcium cis-hexahydrophthalic acid as an example to describe the implementation scheme of the present invention in detail.

[0051] The system for preparing organic carboxylate nucleating agents in a continuous flow environment within an all-aqueous system, as described in this embodiment, includes a first feed pump, a second feed pump, a continuous flow stirred reactor, and a spray dryer. The continuous flow stirred reactor comprises, from bottom to top, a base, a polytetrafluoroethylene (PTFE) sealing plate, a soda-lime glass plate, and a cover plate. The base includes a rounded-corner liquid pool, a magnetic inlet placed inside the rounded-corner liquid pool, and a first inlet passage, a second inlet passage, and an outlet passage connected to the rounded-corner liquid pool. The inner diameter of the outlet passage is 5.8 mm. The diameter and height of the rounded-corner liquid pool are 15 mm and 10 mm, respectively. The first and second inlet passages are perpendicular to each other, and the angles between the first and second inlet passages and the outlet passage are both 135°. The first inlet passage is connected to the outlet of the first feed pump; the second inlet passage is connected to the outlet of the first feed pump; and the outlet passage is connected to the inlet of the spray dryer.

[0052] Based on the system of this embodiment, the preparation method of this embodiment specifically includes the following steps:

[0053] 1) A mixture of cis-1,2-cyclohexanedicarboxylic anhydride and an aqueous solution of sodium hydroxide is used to obtain the first reactant, wherein the concentration of cis-1,2-cyclohexanedicarboxylic anhydride in the first reactant is 1.6 mol·L⁻¹. -1 Calcium chloride was dissolved in water to obtain a calcium chloride concentration of 1.8 mol·L⁻¹. -1 The second reactant.

[0054] 2) The first feed pump delivers the first reactant at a rate of 0.05 mL / min. -1 The first reactant is pumped into the continuous flow stirred reactor at a flow rate of 0.05 mL / min, and the second feed pump delivers the second reactant at a flow rate of 0.05 mL / min. -1 The mixture is pumped into a continuous flow stirred reactor (rotation speed of 800 rpm) at a flow rate of 100 rpm to produce a slurry.

[0055] 3) Pump the slurry into the spray dryer, wherein the drying gas flow rate of the spray dryer is 25 m³ / h. 3 ·h -1 The inlet temperature of the spray dryer is 150℃; the spray gas flow rate of the spray dryer is 1.30m³ / h. 3 ·h -1 The outlet temperature was 80℃, and the nucleating agent calcium cis-hexahydrophthalate was obtained. The coefficient of variation was calculated to be 40%, and the yield was 80%.

[0056] Example 2

[0057] The following describes the implementation scheme of the present invention in detail using the production of the nucleating agent calcium cis-hexahydrophthalic acid as an example.

[0058] The only difference between this embodiment and Embodiment 1 is that the flow rate of the second feed pump is 6.00 mL / min. -1 .

[0059] The production method of this embodiment is exactly the same as that of Example 1. The nucleating agent calcium cis-hexahydrophthalate of this embodiment is prepared according to the production method of Example 1. The coefficient of variation is calculated to be 30% and the yield is 75%.

[0060] Example 3

[0061] The following describes the implementation scheme of the present invention in detail using the production of the nucleating agent calcium cis-hexahydrophthalic acid as an example.

[0062] The only difference between this embodiment and Example 2 is the ratio of the first reactant to the second reactant. Specifically, the concentration of cis-1,2-cyclohexanedicarboxylic anhydride in the first reactant is 0.8 mol·L⁻¹. -1 The concentration of calcium chloride in the second reactant is 0.9 mol·L⁻¹. -1 .

[0063] The production method of this embodiment is exactly the same as that of Example 1. The nucleating agent calcium cis-hexahydrophthalic acid of this embodiment is prepared according to the production method of Example 1. The coefficient of variation is calculated to be 25% and the yield is 70%.

[0064] Example 4

[0065] The following describes the implementation scheme of the present invention in detail using the production of the nucleating agent calcium cis-hexahydrophthalic acid as an example.

[0066] The only difference between this embodiment and embodiment 2 is that the diameter and height of the liquid pool are 26mm and 16mm, respectively.

[0067] The production method of this embodiment is exactly the same as that of Example 1. The nucleating agent calcium cis-hexahydrophthalate of this embodiment is prepared according to the production method of Example 1. The coefficient of variation is calculated to be 22% and the yield is 85%.

[0068] Example 5

[0069] The following describes the implementation scheme of the present invention in detail using the production of the nucleating agent calcium cis-hexahydrophthalic acid as an example.

[0070] The only difference between this embodiment and embodiment 4 is that the inlet temperature of the spray dryer is 200°C and the outlet temperature is 100°C.

[0071] The production method of this embodiment is exactly the same as that of Example 1. The nucleating agent calcium cis-hexahydrophthalic acid of this embodiment is prepared according to the production method of Example 1. The coefficient of variation is calculated to be 20% and the yield is 82%.

[0072] Example 6

[0073] The following describes the implementation scheme of the present invention in detail using the production of the nucleating agent calcium cis-hexahydrophthalic acid as an example.

[0074] The only difference between this embodiment and Embodiment 4 is that the drying gas flow rate of the spray dryer is 20m³ / h. 3 ·h -1 .

[0075] The production method of this embodiment is exactly the same as that of Example 1. The nucleating agent calcium cis-hexahydrophthalic acid of this embodiment is prepared according to the production method of Example 1. The coefficient of variation is calculated to be 18% and the yield is 80%.

[0076] Example 7

[0077] The following describes the implementation scheme of the present invention in detail using the production of the nucleating agent calcium cis-hexahydrophthalic acid as an example.

[0078] The only difference between this embodiment and Embodiment 1 is that the rotational speed of the continuous flow stirred reactor is 1200 rpm.

[0079] The production method of this embodiment is exactly the same as that of Example 1. The nucleating agent calcium cis-hexahydrophthalic acid of this embodiment is prepared according to the production method of Example 1. The coefficient of variation is calculated to be 27% and the yield is 75%.

[0080] Example 8

[0081] The following describes the implementation scheme of the present invention in detail using the production of the nucleating agent calcium cis-hexahydrophthalic acid as an example.

[0082] The only difference between this embodiment and Embodiment 4 is that the spray gas flow rate of the spray dryer is 1.00 m³ / h. 3 ·h -1 .

[0083] The production method in this embodiment is exactly the same as that in Example 1. The nucleating agent calcium cis-hexahydrophthalic acid of this embodiment is prepared according to the production method of Example 1. The coefficient of variation is calculated to be 20% and the yield is 79%.

[0084] Comparative Example 1

[0085] In a 100 mL round-bottom flask equipped with a magnetic stirrer, 10 mL of water, 0.64 g of sodium hydroxide, 1.23 g of cis-1,2-cyclohexanedicarboxylic anhydride, and 1.00 g of calcium chloride were added. The mixture was heated in a water bath to 50 °C and stirred at 800 rpm for 5 h. The product was collected by suction filtration and vacuum dried to obtain the nucleating agent, calcium cis-hexahydrophthalate. The calculated coefficient of variation was 60%, and the yield was 75%.

[0086] In summary, based on the test results of Examples 1-8 and Comparative Example 1, this invention addresses the influencing factors involved in the production process of organic carboxylate nucleating agents. By constructing a cascaded continuous flow reaction system using a continuous flow stirred reactor (CSTR) and a spray dryer, and by rationally optimizing temperature, material flow rate, spray drying gas flow rate, and reactor rotation speed, ensuring compatibility of the reaction modules and better precise control of reaction conditions, the synthesis method in a batch reactor is rationally transferred to the cascaded continuous flow reaction system. This enables efficient and green continuous flow synthesis of organic carboxylate nucleating agents in an all-aqueous system. The resulting organic carboxylate nucleating agents exhibit more uniform particle size distribution, better dispersibility, lower coefficient of variation, and higher yield, demonstrating broad industrialization prospects.

[0087] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the patent application. 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 scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A method for preparing organic carboxylate nucleating agents in a continuous flow process within an all-aqueous system, characterized in that, A system for preparing organic carboxylate nucleating agents using continuous flow in an all-aqueous system, the system comprising a feeding unit, a reaction unit, and a spray drying unit connected in sequence; The feeding unit includes a first feed pump and a second feed pump; The reaction unit includes a continuous flow stirred reactor; the first feed pump and the second feed pump are connected in parallel to the feed inlet of the continuous flow stirred reactor; The spray drying unit includes a spray dryer; the outlet of the continuous flow stirred reactor is connected to the inlet of the spray dryer; The continuous flow stirred reactor includes a base and a cover plate arranged opposite to each other, a sealing plate disposed between the base and the cover plate, and a transparent corrosion-resistant plate disposed between the sealing plate and the cover plate; The base includes a liquid pool, a magnetic element placed inside the liquid pool, and a first inlet passage, a second inlet passage, and an outlet passage connected to the liquid pool; the first inlet passage is connected to the outlet of the first feed pump; the second inlet passage is connected to the outlet of the second feed pump; and the outlet passage is connected to the inlet of the spray dryer. The cover plate and the sealing plate are respectively provided with a first through hole and a second through hole; the diameter of the first through hole and the second through hole is the same as the diameter of the liquid pool, and the diameter of the first through hole and the second through hole is smaller than the diameter of the transparent corrosion-resistant plate; The method specifically includes the following steps: The carboxylic anhydride was dissolved in an aqueous sodium hydroxide solution to obtain the first reactant; The metal chloride is dissolved in water to obtain the second reactant; The first reactant and the second reactant are continuously fed into a continuous flow stirred reactor via a first feed pump and a second feed pump, respectively, to react and obtain the reaction products. The reaction product is continuously fed through the outlet of a continuous flow stirred reactor to a spray dryer for spray drying to obtain the organic carboxylate nucleating agent; the particle size variation coefficient of the organic carboxylate nucleating agent is 10%~50%; The carboxylic anhydride includes one or more of malonic anhydride, glutaric anhydride, adipic anhydride, pimelic anhydride, succinic anhydride, benzoic anhydride, and cis-1,2-cyclohexanedicarboxylic anhydride. The metal chloride includes one or more of sodium chloride, calcium chloride, cadmium chloride, and aluminum chloride; The concentration of carboxylic anhydride in the first reactant is 0.1 mol·L⁻¹. -1 ~5.0 mol·L -1 ; The concentration of the metal chloride in the second reactant is 0.1 mol·L⁻¹. -1 ~5.0 mol·L -1 ; The drying gas flow rate of the spray dryer is 0 mL / min. -1 ~100.00 mL·min -1 The inlet temperature of the spray dryer is 10℃~300℃; the spray gas flow rate of the spray dryer is 0mL·min. -1 ~10.00 mL·min -1 The outlet temperature is 20℃~300℃.

2. The method for preparing organic carboxylate nucleating agents in a continuous flow in an all-aqueous system according to claim 1, characterized in that, The flow rates of both the first and second feed pumps are 0.01 mL / min. -1 ~20mL·min -1 .

3. The method for preparing organic carboxylate nucleating agents in a continuous flow in an all-aqueous system according to claim 1, characterized in that, The liquid pool is a cylindrical liquid pool; The ratio of the diameter of the liquid pool to the height of the liquid pool is 1:0.5~10; The diameter of the liquid pool is 5mm to 200mm; The height of the liquid pool is 5mm~200mm; The inner diameter of the outlet passage is 2mm to 100mm.

4. The method for preparing organic carboxylate nucleating agents in a continuous flow in an all-aqueous system according to claim 1, characterized in that, The angle between the first inlet passage and the second inlet passage is 15° to 180°, and the angle between the first inlet passage and the outlet passage, as well as the angle between the second inlet passage and the outlet passage, is 90° to 172.5°.

5. The method for preparing organic carboxylate nucleating agents in a continuous flow in an all-aqueous system according to claim 1, characterized in that, The base, the cover plate, and the sealing plate are detachably connected by bolts; The cover plate is provided with a locking groove that is adapted to the transparent corrosion-resistant plate; the transparent corrosion-resistant plate is correspondingly embedded in the locking groove; The transparent corrosion-resistant plate is made of either glass or transparent plastic. The sealing plate is made of polytetrafluoroethylene; The rotational speed of the continuous flow stirred reactor is 300 rpm to 1200 rpm.

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