Production system of polylactic acid-glycolic acid copolymer

Abstract

The utility model discloses a polylactic acid-glycolic acid copolymer production system which comprises a polymerization kettle, a first heating interlayer is arranged outside the polymerization kettle, and a polymerization stirring device is arranged in the polymerization kettle. A solid material feeding port, a xylene feeding pipeline, a catalyst feeding pipeline and an ethyl acetate feeding pipeline are arranged at the top end of the polymerization kettle; a waste liquid outlet of the polymerization kettle is connected with a xylene recovery tank through a waste liquid pipeline, and a polymer solution outlet of the polymerization kettle is connected with a precipitation barrel through a polymer solution pipeline; a precipitation stirring device is arranged in the precipitation barrel, and an absolute ethyl alcohol feeding pipeline is arranged at the top of the precipitation barrel. Equipment composition is simple, copolymer performance is stable, and efficiency is high.

Description

Technical Field

[0001] The utility model relates to the technical field of extraction systems, in particular to a production system of a polylactic acid-glycolic acid copolymer. Background Art

[0002] Poly (D, L-lactic acid-polyglycolic acid) copolymer, also known as poly (lactic acid-glycolic acid) copolymer (PLGA), is a degradable functional polymer organic compound with good biocompatibility, non-toxicity, good capsule-forming and film-forming properties. It is widely used in pharmaceutical, medical engineering materials and modern industrial fields.

[0003] However, most of the current poly (D, L-lactic acid-poly (glycolic acid) copolymers are obtained by copolymerization of lactide and glycolide, which is a random copolymerization. The randomness of glycolide and lactide is very strong, resulting in unstable copolymer performance, large differences between products, and difficult application. Therefore, a reaction system with stable copolymer performance, high purity and high efficiency is urgently needed. Utility Model Content

[0004] The utility model aims to solve the technical problems existing in the prior art, and particularly innovatively proposes a production system for a polylactic acid-glycolic acid copolymer, which has simple equipment composition, stable copolymer performance and high efficiency.

[0005] In order to achieve the above-mentioned purpose of the utility model, the utility model provides a production system of polylactic acid-glycolic acid copolymer, comprising a polymerization kettle, a first heating interlayer is arranged outside the polymerization kettle, a polymerization stirring device is arranged inside the polymerization kettle, a solid material addition inlet, a xylene feed pipeline, a catalyst feed pipeline and an ethyl acetate feed pipeline are arranged at the top of the polymerization kettle, the xylene feed pipeline of the polymerization kettle is connected to a xylene metering tank, the xylene metering tank feed pipeline is connected to a xylene storage tank, the catalyst feed pipeline of the polymerization kettle is connected to a catalyst metering tank, the catalyst metering tank feed pipeline is connected to a catalyst storage tank, the ethyl acetate feed pipeline of the polymerization kettle is connected to an ethyl acetate metering tank, and the ethyl acetate metering tank feed pipeline is connected to an ethyl acetate storage tank;

[0006] The top of the polymerization kettle is also provided with a vacuum port, a nitrogen inlet, a waste liquid outlet and a polymer solution outlet. The vacuum port of the polymerization kettle is connected to a vacuum pipeline, the nitrogen inlet of the polymerization kettle is connected to a nitrogen supply pipeline, the waste liquid outlet of the polymerization kettle is connected to a xylene recovery tank through the waste liquid pipeline, and the polymer solution outlet of the polymerization kettle is connected to a precipitation tank through a polymer solution pipeline;

[0007] A precipitation stirring device is arranged in the precipitation barrel, an anhydrous ethanol feeding pipeline is arranged on the top of the precipitation barrel, the anhydrous ethanol feeding pipeline of the precipitation barrel is connected to the anhydrous ethanol metering tank, and the anhydrous ethanol metering tank feeding pipeline is connected to the anhydrous ethanol storage tank.

[0008] In the above scheme: a vacuum port is also provided on the top of the xylene recovery tank, and the vacuum port of the xylene recovery tank is also connected to a vacuum pipeline, so that the xylene waste liquid can be sucked out through the vacuum pipeline.

[0009] In the above scheme: the catalyst storage tank is filled with butyl lithium.

[0010] In the above scheme: a steam inlet pipe and a steam outlet pipe are arranged on the first heating interlayer, and heating is performed by steam, so that the heating is more uniform.

[0011] In the above scheme: a temperature detection device is provided on the first heating interlayer, and electric valves are provided on the steam inlet pipe and the steam outlet pipe, which can adjust the flow of steam according to different steps, thereby adjusting the heating temperature.

[0012] In the above scheme: the water content of xylene in the xylene storage tank is ≤10ppm.

[0013] According to the proportion of ingredients, lactide and glycolide are added into the polymerization kettle from the solid feed port, and the air inside the polymerization kettle is extracted through the vacuum pipeline until the air pressure inside the polymerization kettle is ≦-0.090Mpa and maintained for 10 minutes. Then nitrogen is filled into the polymerization kettle through the nitrogen supply pipeline and the gas is replaced for 10 minutes.

[0014] The polymerization kettle is preheated through the first heating interlayer. After the preheating is completed, xylene is added into the polymerization kettle through the xylene feeding pipeline, and the polymerization stirring device is started, the speed is adjusted to 200-500r / min, and the temperature is gradually increased to completely dissolve the lactide and glycolide.

[0015] After lactide and glycolide are completely dissolved and the solution is heated to 100°C, the temperature is maintained for 10 minutes, and then butyl lithium solution is added to the polymerization kettle through the catalyst feed line. The butyl lithium solution is used as a catalyst to improve the reaction efficiency.

[0016] When a large number of small bubbles appear and stirring becomes difficult, increase stirring and continue to stir slowly and keep warm for 1.5 hours. Stop heating, let it stand overnight, and cool naturally to room temperature. Extract the surface solvent xylene in the polymerization kettle into the xylene recovery tank through the vacuum pipeline of the xylene recovery tank. Then add ethyl acetate to the polymerization kettle through the ethyl acetate feed pipeline, start the polymerization stirring device and the first heating interlayer, and completely dissolve the polymer.

[0017] The completely dissolved polymer was pressed into the precipitation barrel through the nitrogen supply pipeline, the precipitation stirring device was started to the highest speed, and 5L of anhydrous ethanol was quickly added to precipitate the polymer. The mixture was stirred at high speed for 10 minutes and allowed to settle.

[0018] In summary, due to the adoption of the above technical scheme, the beneficial effects of the utility model are: by dissolving lactide and glycolide, adding a suitable catalyst at a given reaction temperature, lactide and glycolide are ring-opened polymerized to generate PLGA random copolymers. The nitrogen supply pipeline and vacuum pipeline provided can replace the air inside the polymerization kettle, thereby improving the safety of the reaction. The first heating interlayer provided can preheat lactide and glycolide, and then add xylene to completely dissolve lactide and glycolide. Then, butyl lithium is added to the polymerization kettle as a catalyst to increase the reaction rate. The set precipitation barrel provided can accommodate the material after the polymerization reaction, allowing it to stand and cool, and purification can be performed after standing and cooling. The first heating stirring tank emptied during the standing and cooling process can be used for the next batch of reaction operations, thereby improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0020] Figure 1 It is a system schematic diagram of the utility model. DETAILED DESCRIPTION

[0021] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0022] like Figure 1 As shown, a production system of polylactic acid-glycolic acid copolymer includes a polymerization kettle 1, and a first heating interlayer 3 is arranged outside the polymerization kettle 1. A steam inlet pipe and a steam outlet pipe are arranged on the first heating interlayer 3, and heating is performed by steam, so that the heating is more uniform. A temperature detection device is arranged on the first heating interlayer 3, and electric valves are arranged on the steam inlet pipe and the steam outlet pipe. The flow rate of the steam inlet pipe and the steam outlet pipe is adjusted by the electric valve, so as to adjust to the temperature required for different steps. The heating temperature of the first heating interlayer 3 is 0-120° to ensure that the polymer is completely dissolved.

[0023] A polymerization stirring device 2 is provided in the polymerization kettle 1, and a solid material inlet 14, a xylene feed pipeline, a catalyst feed pipeline and an ethyl acetate feed pipeline are provided at the top of the polymerization kettle 1. The xylene feed pipeline of the polymerization kettle 1 is connected to a xylene metering tank 4, and the feed pipeline of the xylene metering tank 4 is connected to a xylene storage tank 5. The xylene storage tank 5 contains distilled xylene, and the water content of the xylene is ≤10ppm.

[0024] The catalyst feed line of the polymerization kettle 1 is connected to the catalyst metering tank 4, and the feed line of the catalyst metering tank 4 is connected to the catalyst storage tank 5. The catalyst storage tank 5 contains butyl lithium. The ethyl acetate feed line of the polymerization kettle 1 is connected to the ethyl acetate metering tank 4, and the feed line of the ethyl acetate metering tank 4 is connected to the ethyl acetate storage tank 5.

[0025] The top of the polymerization kettle 1 is also provided with a vacuum port, a nitrogen inlet, a waste liquid outlet and a polymer solution outlet. The vacuum port of the polymerization kettle 1 is connected to a vacuum pipeline, and the nitrogen inlet of the polymerization kettle 1 is connected to a nitrogen supply pipeline. The waste liquid outlet of the polymerization kettle 1 is connected to the xylene recovery tank 8 through the waste liquid pipeline, and the polymer solution outlet of the polymerization kettle 1 is connected to the precipitation tank 9 through the polymer solution pipeline. The top of the xylene recovery tank 8 is also provided with a vacuum port, and the vacuum port of the xylene recovery tank 8 is also connected to a vacuum pipeline, so that the xylene waste liquid can be sucked out through the vacuum pipeline.

[0026] A sedimentation stirring device is arranged in the sedimentation barrel 9 , and an anhydrous ethanol feeding pipeline is arranged on the top of the sedimentation barrel 9 . The anhydrous ethanol feeding pipeline of the sedimentation barrel 9 is connected to the anhydrous ethanol metering tank 10 , and the feeding pipeline of the anhydrous ethanol metering tank 10 is connected to the anhydrous ethanol storage tank 11 .

[0027] When in use, firstly, lactide and glycolide are added into the polymerization kettle 1 from the solid feed port according to the proportion of ingredients, and the air inside the polymerization kettle 1 is extracted through the vacuum pipeline until the air pressure inside the polymerization kettle 1 is ≦-0.090Mpa, and maintained for 10 minutes. Then, nitrogen is filled into the polymerization kettle 1 through the nitrogen supply pipeline, and the gas is replaced for 10 minutes.

[0028] The polymerization kettle 1 is preheated through the first heating interlayer 3. After the preheating is completed, xylene is added into the polymerization kettle 1 through the xylene feeding pipeline, and the polymerization stirring device 2 is started, the rotation speed is adjusted to 200-500r / min, and the temperature is gradually increased to completely dissolve the lactide and glycolide.

[0029] When lactide and glycolide are completely dissolved and the solution is heated to 100°C, the temperature is maintained for 10 minutes, and then butyl lithium solution is added to the polymerization reactor 1 through the catalyst feed line. The butyl lithium solution is used as a catalyst to improve the reaction efficiency.

[0030] When a large number of small bubbles appear and stirring becomes difficult, increase stirring and continue to stir slowly and keep warm for 1.5 hours. Stop heating, let it stand overnight, and cool naturally to room temperature. The surface solvent xylene in the polymerization kettle 1 is extracted into the xylene recovery tank 8 through the vacuum pipeline of the xylene recovery tank 8. Then add ethyl acetate to the polymerization kettle 1 through the ethyl acetate feed pipeline, start the polymerization stirring device 2 and the first heating interlayer 3, and completely dissolve the polymer.

[0031] The completely dissolved polymer is pressed into the precipitation barrel 9 through the nitrogen supply pipeline, the precipitation stirring device is started to the highest speed, and 5L of anhydrous ethanol is quickly added to precipitate the polymer, and the mixture is stirred at a high speed for 10 minutes and allowed to settle.

Claims

1. A production system of polylactic acid-co-glycolic acid, characterized in that: The invention comprises a polymerization kettle (1), wherein a first heating interlayer (3) is arranged outside the polymerization kettle (1), a polymerization stirring device (2) is arranged inside the polymerization kettle (1), and a solid material addition port (14), a xylene feed pipeline, a catalyst feed pipeline and an ethyl acetate feed pipeline are arranged at the top of the polymerization kettle (1), the xylene feed pipeline of the polymerization kettle (1) is connected to a xylene metering tank (4), the feed pipeline of the xylene metering tank (4) is connected to a xylene storage tank (5), the catalyst feed pipeline of the polymerization kettle (1) is connected to a catalyst metering tank (12), the feed pipeline of the catalyst metering tank (12) is connected to a catalyst storage tank (13), the ethyl acetate feed pipeline of the polymerization kettle (1) is connected to an ethyl acetate metering tank (6), and the feed pipeline of the ethyl acetate metering tank (6) is connected to an ethyl acetate storage tank (7); The top of the polymerization kettle (1) is also provided with a vacuum port, a nitrogen inlet, a waste liquid outlet and a polymer solution outlet. The vacuum port of the polymerization kettle (1) is connected to a vacuum pipeline, the nitrogen inlet of the polymerization kettle (1) is connected to a nitrogen supply pipeline, the waste liquid outlet of the polymerization kettle (1) is connected to a xylene recovery tank (8) via the waste liquid pipeline, and the polymer solution outlet of the polymerization kettle (1) is connected to a sedimentation tank (9) via a polymer solution pipeline. A precipitation stirring device is arranged in the precipitation barrel (9), an anhydrous ethanol feeding pipeline is arranged on the top of the precipitation barrel (9), the anhydrous ethanol feeding pipeline of the precipitation barrel (9) is connected to an anhydrous ethanol metering tank (10), and the feeding pipeline of the anhydrous ethanol metering tank (10) is connected to an anhydrous ethanol storage tank (11).

2. The production system of a poly(lactic acid-co-glycolic acid) copolymer according to claim 1, characterized in that: The top of the xylene recovery tank (8) is also provided with a vacuum port, and the vacuum port of the xylene recovery tank (8) is also connected to a vacuum pipeline.

3. A production system of poly(lactic acid-co-glycolic acid) according to claim 2, characterized in that: The catalyst storage tank (13) contains butyl lithium.

4. The production system of a poly(lactic acid-co-glycolic acid) copolymer according to claim 1, characterized in that: The first heating interlayer (3) is provided with a steam inlet pipe and a steam outlet pipe.

5. The production system of a poly(lactic acid-co-glycolic acid) copolymer according to claim 4, characterized in that: The first heating interlayer (3) is provided with a temperature detection device, and the steam inlet pipe and the steam outlet pipe are both provided with electric valves.

6. The production system of a poly(lactic acid-co-glycolic acid) copolymer according to claim 1, characterized in that: The water content of xylene in the xylene storage tank (5) is ≤10 ppm.

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