Polyolefin elastomer solution devolatilization system and method

Abstract

The invention discloses a polyolefin elastomer solution devolatilization system and a polyolefin elastomer solution devolatilization method. The system comprises a horizontal double-shaft kneading devolatilization device and a double-screw extrusion devolatilization machine, a high-temperature atomizer is arranged at a feeding hole of the horizontal double-shaft kneading devolatilization device; the high-temperature atomizer comprises an atomizing nozzle, a gas heater and an air blower; a devolatilization opening is formed above the horizontal double-shaft kneading devolatilization device and is sequentially connected with a condenser and a vacuum pump; a discharge hole of the devolatilization device is connected with a discharge screw rod; a feeding port of the double-screw extrusion devolatilization machine is connected with a discharging screw, a devolatilization port is formed in the upper portion of the double-screw extrusion devolatilization machine and sequentially connected with a condenser and a vacuum pump, and a devolatilized product outlet is formed in the tail of the devolatilization machine. According to the invention, the horizontal double-shaft kneading devolatilization device and the double-screw extrusion devolatilization machine are matched with each other, and the high-temperature atomizer is assisted, so that a large-area heat transfer effect is realized, an efficient devolatilization effect is further realized, and a polymer product with lower residual volatile component content is obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of elastomers, and in particular to a polyolefin elastomer solution devolatilization system and method. Background Art

[0002] Polyolefin elastomers represented by ethylene-α-olefin copolymer elastomers and ethylene-propylene rubber are usually prepared by solution polymerization. The material at the outlet of the reactor contains a large amount of volatiles such as ethylene, comonomers, and solvents, which need to be deeply removed to meet the requirements of downstream applications. The viscosity of the polymer solution increases significantly with the decrease of the volatile content during the devolatilization process. In the early stage of devolatilization, the solid content and viscosity of the system are relatively low, and the volatiles are removed by flash evaporation and foaming devolatilization, which requires high heat, generally provided by feed preheating and devolatilizer jacket heating; in the middle and late stages of devolatilization, as the solid content and viscosity increase, the system enters the diffusion devolatilization stage, and the system flow and volatile mass transfer are difficult. Existing processes mostly use multi-stage devolatilization to meet the devolatilization requirements of different stages.

[0003] At present, the devolatilization technology of polyolefin elastomers mostly uses a flash evaporator for pre-devolatilization, concentrates the low-solid content polymer solution, and then deeply devolatilizes it through static or dynamic devolatilization equipment. Patent CN113877498A uses a first-stage flash evaporator with a twin-screw extruder devolatilizer. After two stages of devolatilization, the volatile content of the styrene-acrylonitrile copolymer (SAN resin) product reaches 600-700ppm; Patent CN115612010A uses two-stage flash evaporation and a third-stage strip devolatilization to treat polyolefin solution, and the volatile content of the product is reduced to 500ppm; Patent CN118384522A combines two-stage flash evaporation and twin-screw extrusion devolatilization to treat ethylene-α-olefin copolymer elastomer (POE) solution. However, the multi-stage flash evaporation process requires repeated heating of the polymer solution to about 280°C, which can easily lead to thermal decomposition of the polymer. At the same time, the system is highly viscous in the later stage of devolatilization, making it difficult to flow in the static devolatilizer.

[0004] The direct devolatilization process for cis-1,4-butadiene rubber (SBR), developed by LIST (Switzerland), "Safrit BT, Diener A E. Kneader technology for the direct devolatilization of temperature-sensitive elastomers [C]. Society of Plastics Engineers Annual Technical Conference, 2008," utilizes a horizontal single-shaft kneader devolatilizer for the first and second stages of devolatilization, respectively, eliminating the need for repeated high-temperature heating of the rubber solution. However, under these process conditions, cis-1,4-butadiene rubber undergoes phase separation as volatiles are removed, transforming into solid particles. Devolatilization in the middle and later stages is essentially diffusion of volatiles within the solid particles. Furthermore, the initial flash evaporation of solvent can cause a sudden drop in system temperature, leading to premature solidification and precipitation of the polymer. Raising the process temperature above the polymer's melting point but below its decomposition temperature can shift the diffusion of volatiles in the solid to mass transfer in the liquid, increasing the diffusion rate. However, the initial flash evaporation of solvent, resulting in a drop in system temperature and reduced devolatilization efficiency, further impacting equipment capacity, remains to be addressed. Summary of the Invention

[0005] The present invention addresses the problem of low devolatilization efficiency during the preparation of elastomers and provides a devolatilization system for use in the preparation of polyolefin elastomers. The system utilizes a horizontal twin-shaft kneading devolatilizer and a twin-screw extruder devolatilizer in combination with a high-temperature atomizer to achieve a large-area heat transfer effect, achieve a highly efficient devolatilization effect, and obtain a polymer product with a lower residual volatile content.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A polyolefin elastomer solution devolatilization system, comprising a horizontal twin-shaft kneading devolatilizer and a twin-screw extruder devolatilizer;

[0008] The horizontal biaxial kneading devolatilizer is provided with a high-temperature atomizer at the feed inlet, and the high-temperature atomizer includes an atomizing nozzle, a gas heater and a blower; a devolatilizer is provided above the horizontal biaxial kneading devolatilizer, and the devolatilizer is connected to a condenser and a vacuum pump in sequence; the discharge port of the horizontal biaxial kneading devolatilizer is connected to a discharge screw;

[0009] The feed port of the twin-screw extruder devolatilizer is connected to the discharge screw, and a devolatilization port is provided on the top. The devolatilization port is connected to the condenser and the vacuum pump in sequence. The tail of the twin-screw extruder devolatilizer is provided with an outlet for the devolatilized product.

[0010] The present invention adopts a two-stage devolatilization based on a horizontal biaxial kneading devolatilizer and a twin-screw extruder devolatilizer. A high-temperature atomizer is provided at the feed port of the horizontal biaxial kneading devolatilizer. The low-solid content polymer solution is broken into droplets by means of an atomizing nozzle. The particle size of these droplets is generally 20 to 200 μm, which has a large heat and mass transfer area. In the short period before the droplets fall into the liquid phase body in the devolatilizer, a large amount of volatile matter is quickly removed by flash evaporation, which simplifies the devolatilization process, helps solve the heat transfer problem in the flash evaporation stage in the early stage of devolatilization, improves the bubbling devolatilization and diffusion devolatilization efficiency in the middle and late stages of devolatilization, improves the processing capacity, and can obtain a polymer product with a lower residual volatile matter content.

[0011] The horizontal double-shaft kneading devolatilizer is a horizontal cylindrical container, wherein two kneading shafts rotating in the same direction or in the opposite direction are arranged in the transverse direction, and kneading elements are installed on the shafts.

[0012] The twin-screw extruder devolatilizer is a horizontal cylindrical container, and two groups of screws that rotate in the same direction or in the opposite direction and mesh with each other are arranged in the transverse direction inside.

[0013] The atomizing nozzle of the high-temperature atomizer is an airflow nozzle or a pressure-airflow nozzle, with a liquid channel and a gas channel inside, a polyolefin elastomer solution feed port on the top, and an atomizing gas inlet on the side;

[0014] Preferably, the atomizing gas comprises one or more of N2, CO2, and water vapor. The atomizing gas is generated by a blower into a high-speed airflow. After being heated by a gas heater, it enters the atomizing nozzle, forming a spiral downward-spinning airflow in the gas channel. At the atomizing nozzle outlet, the friction between the high-speed airflow and the liquid causes the polyolefin elastomer solution to break into droplets.

[0015] Preferably, the temperature of the droplets at the feed port of the horizontal twin-shaft kneading devolatilizer is controlled by a gas heater, and the temperature of the liquid phase body in the cylinder is controlled by a jacket; the temperature of the twin-screw extruder devolatilizer is controlled by a jacket.

[0016] The present invention also provides a method for devolatilizing a polyolefin elastomer solution using the devolatilization system, comprising the steps of:

[0017] The polyolefin elastomer solution is introduced into a horizontal twin-shaft kneading devolatilizer through a high-temperature atomizer for flash pre-devolatilization, and then conveyed to a twin-screw extruder devolatilizer through a discharge screw for secondary devolatilization to obtain a polymer product with low volatile content.

[0018] The liquid level of the polyolefin elastomer solution in the horizontal biaxial kneading devolatilizer is 25% to 50%.

[0019] The polyolefin elastomer solution is operated in a horizontal biaxial kneading devolatilizer at an absolute pressure of 2 to 20 kPa, a devolatilization temperature of 110 to 200° C., and a residence time of 5 to 30 minutes;

[0020] The operating absolute pressure of the polyolefin elastomer solution in the twin-screw extruder devolatilizer is 0.1-5 kPa, the devolatilization temperature is 110-200° C., and the residence time is 5-10 minutes.

[0021] The polyolefin elastomer includes any one or more of ethylene-α-olefin random copolymer elastomer, block copolymer elastomer, EPDM rubber, EPDM rubber, metallocene EPDM rubber and the like.

[0022] The low-solids, low-viscosity polymer solution obtained after the polymerization reaction is atomized at high temperature and injected into a horizontal twin-shaft kneading devolatilizer in the form of droplets. This helps increase the gas-liquid mass transfer area and improve flash evaporation efficiency. It also compensates for the heat required for flash evaporation at the inlet, resolving issues such as rapid temperature drop, increased viscosity, glue agglomeration, and flow difficulties in the first-stage devolatilization inlet. In addition to atomizing the polymer solution and providing the heat required for flash evaporation, the atomizing gas also acts as a devolatilizer, reducing the partial pressure of volatiles in the gas phase, thereby helping to produce polymer products with lower residual volatile content.

[0023] Preferably, the volatile content of the low volatile content polymer product is below 100 ppm.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) In the present invention, the polymer solution is atomized at high temperature before entering a horizontal biaxial kneading devolatilizer, thereby resolving problems such as rapid temperature drop, increased viscosity, glue agglomeration, and flow difficulties in the first-stage devolatilization inlet. In addition to atomizing the polymer solution and providing the heat required for flash evaporation of the droplets, the atomizing gas also acts as a devolatilization aid, reducing the partial pressure of volatiles in the gas phase, thereby helping to obtain a polymer product with a lower residual volatile content.

[0026] (2) The devolatilization system of the present invention uses a first-stage horizontal twin-shaft kneading devolatilization and a second-stage twin-screw extrusion devolatilization to enhance the flow film formation and surface renewal in the foaming devolatilization and diffusion devolatilization stages, thereby deeply removing volatiles.

[0027] (3) Compared with the multi-stage flash evaporation process, the devolatilization method of the present invention avoids the thermal decomposition of the polymer caused by repeated heating of the polymer solution, simplifies the process and reduces energy consumption.

[0028] (4) Due to the improvement of devolatilization capacity by introducing high-temperature atomization, in the secondary twin-screw extrusion devolatilization process, even if the rotation speed is appropriately reduced, the product can still reach the expected residual volatile content, which is more beneficial for the devolatilization of shear-sensitive polymer materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a polyolefin elastomer solution devolatilization system in an embodiment of the present invention, wherein 1 is a horizontal biaxial kneading devolatilizer, 2 is an atomizing nozzle, 3 is a polymer solution feed port, 4 is a gas heater, 5 is an atomizing gas inlet, 6 is a blower, 7 is a devolatilizer, 8 is a vacuum pump, 9 is a condenser, 10 is a discharge screw, 11 is a twin-screw extruder devolatilizer, 12 is a devolatilizer, 13 is a vacuum pump, 14 is a reflux condenser, and 15 is a polymer product discharge port.

[0030] Figure 2 These are the molecular weight distribution curves of the ethylene / 1-octene copolymer elastomers (EOC) in Examples 1 to 4 of the present invention and Comparative Examples 1 to 2 measured before and after devolatilization.

[0031] Figure 3 The molecular weight distribution curves of ethylene propylene diene monomer (EPDM) before and after devolatilization in Examples 5-6 of the present invention and Comparative Examples 3-4 are measured. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with embodiment. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Those skilled in the art will make modifications or equivalent substitutions based on understanding the technical solution of the present invention, without departing from the spirit and scope of the technical solution of the present invention, and all should be encompassed within the protection scope of the present invention.

[0033] like Figure 1 As shown, the present invention provides a method for devolatilizing a polyolefin elastomer solution, wherein the system used in the method comprises a horizontal biaxial kneading devolatilizer (1) and a twin-screw extruder devolatilizer (11);

[0034] The feed port of the horizontal biaxial kneading devolatilizer (1) is provided with a high-temperature atomizer, which includes an atomizing nozzle (2), a gas heater (4) and a blower (6); a devolatilizer port (7) is provided above the horizontal biaxial kneading devolatilizer, and the devolatilizer port (7) is connected to a condenser (9) and a vacuum pump (8) in sequence;

[0035] The discharge port of the horizontal twin-shaft kneading devolatilizer is connected to a discharge screw (10); the feed port of the twin-screw extrusion devolatilizer (11) is connected to the discharge screw (10), and a devolatilization port (12) is provided above the twin-screw extrusion devolatilizer. The devolatilization port is connected to a reflux condenser (14) and a vacuum pump (13) in sequence. The tail of the twin-screw extrusion devolatilizer is provided with an outlet for the devolatilized product.

[0036] The horizontal twin-shaft kneading devolatilizer (1) is a horizontal cylindrical container, and is provided with two kneading shafts rotating in the same direction or in the opposite direction along the horizontal direction inside, and kneading elements are installed on the shafts. The twin-screw extruder devolatilizer is a horizontal cylindrical container, and is provided with two sets of screws rotating in the same direction or in the opposite direction and meshing with each other along the horizontal direction inside.

[0037] The atomizing nozzle of the high-temperature atomizer is a pressure-airflow nozzle with a liquid channel and a gas channel inside. The upper part is a polyolefin elastomer solution feed port (3), and the side part is an atomizing gas inlet (5); the droplets at the feed port of the horizontal biaxial kneading devolatilizer (1) are temperature-controlled by a gas heater, and the liquid phase body in the barrel is temperature-controlled by a jacket; the twin-screw extruder devolatilizer (11) is temperature-controlled by a jacket.

[0038] The devolatilization method of a polyolefin elastomer solution specifically includes: a two-stage devolatilization based on a horizontal twin-shaft kneading devolatilizer and a twin-screw extrusion devolatilizer, wherein a polyolefin elastomer solution with a solid content of 15 to 20% is introduced into the upper feed port of the horizontal twin-shaft kneading devolatilizer through a high-temperature atomizer for high-temperature atomization to achieve flash evaporation pre-devolatilization; then, a first-stage horizontal twin-shaft kneading devolatilization and a second-stage twin-screw extrusion devolatilization are performed to achieve deep removal of volatiles, ultimately obtaining a polymer product with a volatile content of less than 100 ppm.

[0039] The residual volatile matter of the devolatilized polymer product was determined by headspace-gas chromatography (HS-GC). The gas chromatography equipment used was a Shimadzu GC-2010PRO from Japan, equipped with a flame ionization detector (FID). The chromatographic column used was a non-polar gas chromatography column SH-5 with a column length of 30 m, an inner diameter of 0.32 mm, and a film thickness of 0.25 μm. The headspace equipment was an HS-12A PRO produced by Shanghai Star Analytical Instrument Co., Ltd. The headspace conditions are shown in Table 1. The number average molecular weight (M) of the polymer was n ), weight average molecular weight (M w ) and molecular weight distribution (PDI) were determined using PL-GPC 220 (GPC) from PL Company, UK.

[0040] Table 1 Headspace-gas chromatography conditions

[0041]

[0042]

[0043] In the following examples and comparative examples, the devolatilization process of the present invention was used to conduct devolatilization experiments on EOC solution and EPDM solution. The EOC used was a product of Saudi Basic Industries Corporation with a brand name of EOC-1, and its number average molecular weight (M n ) is 8.5×10 4 , weight average molecular weight (M w ) is 2.7×10 5 , molecular weight distribution index (PDI) is 3.2, melt index is 0.45g / 10min, and melting temperature is 57°C;

[0044] The EPDM used is the product of brand J-3080P produced by Jilin Petrochemical Company. n 6.9×10 4 , M w 3.5×10 5 , PDI is 5.1, melt index is 0.50g / 10min, and melting temperature is 29°C. Since EOC is a shear-insensitive polymer and EPDM is a shear-sensitive polymer, the high shear rate of the twin-screw extruder devolatilizer is more likely to cause shear chain scission of EPDM.

[0045] With reference to the solid content level of the material at the discharge port of the polymerization reactor in an actual solution polymerization process, an EOC-n-hexane solution with a solid content of 20% was prepared and dissolved at 140°C. EOC devolatilization experiments were carried out in Examples 1 to 4 and Comparative Examples 1 to 2. An EPDM-n-hexane / norbornene solution with a solid content of 15% was prepared, in which the norbornene content was 5%, and dissolved at 140°C. EPDM devolatilization experiments were carried out in Examples 5 to 6 and Comparative Examples 3 to 4.

[0046] In Comparative Examples 1 to 4, the high-temperature atomizer at the feed port of the horizontal biaxial devolatilizer (1) was removed, and the polymer solution was allowed to enter the liquid phase directly from the feed port. Devolatilization experiments of EOC-n-hexane solution and EPDM-n-hexane / norbornene solution were carried out.

[0047] Example 1

[0048] The EOC-n-hexane solution was devolatilized at a feed rate of 80 kg / h. The atomizing nozzle (2) at the feed port of the horizontal biaxial kneading devolatilizer (1) was a pressure-airflow type nozzle with a height of 200 mm. The diameters of the liquid and gas channels gradually contracted from top to bottom, with the liquid channel diameter gradually contracting from 16 mm to 12 mm, and the gas channel diameter gradually contracting from 100 mm to 24 mm. N2 was used as the atomizing gas, the blower (5) had a ventilation flow rate of 1000 L / h, and the temperature of the gas heater (4) was set at 160°C. The cylinder volume of the horizontal biaxial kneading devolatilizer (1) was 12 L, the rotation speed was 30 rpm, the liquid level of the polymer solution in the cylinder was 35%, and the residence time was 10 min. The jacket temperature was set at 140°C, and the operating pressure (absolute pressure) was 5 kPa.

[0049] The twin-screw extruder devolatilizer (16) had a barrel volume of 10 L and a screw speed of 20 rpm; the residence time of the polymer solution was 9 min; the jacket temperature was set at 140° C.; and the operating pressure (absolute pressure) was 1 kPa.

[0050] The residual volatile content of the first-stage devolatilization sample obtained from the sampling port of the discharge screw (10) was measured; the residual volatile content and molecular weight (including M n 、M w The results of sample testing are shown in Table 2 and Figure 2 The results show that no significant shear chain breaking phenomenon occurs during the devolatilization process of EOC.

[0051] Example 2

[0052] Based on Example 1, the feed flow rate was replaced with 140 kg / h, and the other operating conditions remained unchanged. The sample test results are shown in Table 2 and Figure 2 As shown. Compared with Example 1, the volatile content of the first-stage devolatilization sample and the product increased, and the molecular weight of EOC did not change significantly. This is because after the feed flow rate is increased, the liquid level of the polymer solution in the horizontal biaxial kneading devolatilizer (1) increases, the film forming area decreases, and the gas-liquid volume mass transfer coefficient decreases, so the devolatilization efficiency in the first-stage devolatilization decreases. Therefore, in the process of devolatilization of polyolefin elastomers, it is necessary to balance the relationship between processing volume and product quality.

[0053] Example 3

[0054] On the basis of Example 1, the atomizing gas (5) was replaced with pure water vapor, and the other operating conditions remained unchanged. The sample test results are shown in Table 2 and Figure 2Compared with Example 1, the volatile content of the product is reduced, and the molecular weight does not change significantly. This is because water vapor, as a devolatilizing agent, has a higher specific heat capacity than N2, which can provide more heat for the devolatilization of the polymer solution, resulting in a better devolatilization effect.

[0055] Example 4

[0056] On the basis of Example 1, the ventilation flow rate of the blower (5) was replaced with 1500L / h, and the other operating conditions remained unchanged. The sample test results are shown in Table 2 and Figure 2 Compared with Example 1, the volatile content of the product is reduced, and the molecular weight does not change significantly. This is because increasing the high-temperature atomizer gas flow rate reduces the droplet size formed, increases the heat and mass transfer area of ​​the droplets, and improves the devolatilization rate of the volatiles during the flash evaporation stage.

[0057] Example 5

[0058] The EPDM-n-hexane / norbornene solution was devolatilized. Based on Example 1, the temperature of the gas heater (4) was replaced with 150°C, the jacket temperature of the horizontal biaxial kneading devolatilizer (1) was replaced with 130°C, and the jacket temperature of the twin-screw extruder devolatilizer (11) was replaced with 130°C. The other operating conditions remained unchanged. The sample test results are shown in Table 2 and Figure 3 The results show that the molecular weight is reduced to a certain extent compared with the EPDM sample before devolatilization. This is because EPDM is a shear-sensitive polymer material, and the strong shearing effect of the twin-screw extruder devolatilizer (11) causes significant shear chain scission.

[0059] Example 6

[0060] On the basis of Example 5, the screw speed of the twin-screw extruder devolatilizer (11) was replaced with 10 rpm. The sample test results are shown in Table 2 and Figure 3 Compared with Example 5, the volatile matter content of the product is increased, but still below 100 ppm, and the molecular chain breakage is also weakened at the low shear rate of the twin-screw extruder devolatilizer (11).

[0061] Comparative Example 1

[0062] On the basis of Example 1, the high temperature atomizer at the feed port of the horizontal double-shaft devolatilizer (1) was removed, so that the polymer solution directly entered the liquid phase from the feed port, and the other operating conditions remained unchanged. The sample test results are shown in Table 2 and Figure 2 As shown, it is difficult to reduce the volatile content of the final product to below 100 ppm without the introduction of a high-temperature atomizer. In contrast, the introduction of a high-temperature atomizer in Example 1 significantly reduced the residual volatile content of the EOC product and had little effect on the molecular weight of the EOC.

[0063] Comparative Example 2

[0064] Based on Comparative Example 1, the feed flow rate was changed to 140 kg / h, and the other operating conditions remained unchanged. The sample test results are shown in Table 2 and Figure 2 As shown. Compared with Comparative Example 1, the volatile content of the product increased, but the molecular weight of the EOC did not change significantly. This is because, after the feed flow rate increased, on the one hand, the liquid level in the horizontal twin-shaft kneading devolatilizer (1) increased, resulting in a decrease in the gas-liquid volumetric mass transfer coefficient; on the other hand, the agglomeration and flow difficulties of the polymer solution in the liquid phase of the horizontal twin-shaft kneading devolatilizer (1) became more significant.

[0065] Comparative Example 3

[0066] On the basis of Example 5, the high temperature atomizer at the feed inlet of the horizontal double-shaft devolatilizer (1) was removed, and the other operating conditions remained unchanged. The sample test results are shown in Table 2 and Figure 3 As shown. Comparison with Example 5 shows that the introduction of the high-temperature atomizer significantly reduces the residual volatile content of the EPDM product, and the shear chain scission of EPDM during the devolatilization process is mainly caused by the high shear rate of the twin-screw extruder devolatilizer (11), and the high-temperature atomizer does not cause shear chain scission of EPDM.

[0067] Comparative Example 4

[0068] On the basis of comparative example 3, the screw speed of the twin-screw extruder devolatilizer (11) was replaced with 10 rpm, and the other operating conditions remained unchanged. The sample test results are shown in Table 2 and Figure 3 As shown. Comparison with Comparative Example 3 shows that the product's volatile content increased, but shear chain scission was reduced. This indicates that for shear-sensitive polymer materials such as EPDM, the method of directly injecting the polymer solution into the liquid phase from the feed port is difficult to reduce the product's volatile content to the desired level while minimizing molecular chain scission caused by high shear rates. In contrast, the introduction of a high-temperature atomizer in Example 6 achieves ideal devolatilization even at lower screw speeds and shear rates.

[0069] Table 2 Test results of samples after devolatilization in Examples and Comparative Examples

[0070]

[0071]

[0072] From the above embodiments and comparative examples, it can be seen that the introduction of a high-temperature atomizer can significantly reduce the residual volatile content of polyolefin elastomers after devolatilization, and has little effect on the molecular weight of the devolatilized product. It has universal applicability for shear-insensitive and shear-sensitive polymer materials.

Claims

1. A polyolefin elastomer solution devolatilization system, characterized in that: It includes horizontal twin-shaft kneading devolatilizer and twin-screw extruder devolatilizer; The horizontal biaxial kneading devolatilizer is provided with a high-temperature atomizer at the feed inlet, and the high-temperature atomizer includes an atomizing nozzle, a gas heater and a blower; a devolatilizer is provided above the horizontal biaxial kneading devolatilizer, and the devolatilizer is connected to a condenser and a vacuum pump in sequence; the discharge port of the horizontal biaxial kneading devolatilizer is connected to a discharge screw; The feed port of the twin-screw extruder devolatilizer is connected to the discharge screw, and a devolatilization port is provided on the top. The devolatilization port is connected to the condenser and the vacuum pump in sequence. The tail of the twin-screw extruder devolatilizer is provided with an outlet for the devolatilized product.

2. The polyolefin elastomer solution devolatilization system according to claim 1, characterized in that: The horizontal double-shaft kneading devolatilizer is a horizontal cylindrical container, wherein two kneading shafts rotating in the same direction or in the opposite direction are arranged in the transverse direction, and kneading elements are installed on the shafts.

3. The polyolefin elastomer solution devolatilization system according to claim 1, characterized in that: The twin-screw extruder devolatilizer is a horizontal cylindrical container, and two groups of screws that rotate in the same direction or in the opposite direction and mesh with each other are arranged in the transverse direction inside.

4. The polyolefin elastomer solution devolatilization system according to claim 1, characterized in that: The atomizing nozzle of the high-temperature atomizer is an airflow nozzle or a pressure-airflow nozzle, with a liquid channel and a gas channel inside, a polyolefin elastomer solution feed port on the top, and an atomizing gas inlet on the side; The atomizing gas includes one or more of N2, CO2, and water vapor.

5. The polyolefin elastomer solution devolatilization system according to claim 1, characterized in that: The temperature of the mist droplets at the feed port of the horizontal twin-shaft kneading devolatilizer is controlled by a gas heater, and the temperature of the liquid phase body in the cylinder is controlled by a jacket; the temperature of the twin-screw extruder devolatilizer is controlled by a jacket.

6. A method for devolatilizing a polyolefin elastomer solution using the devolatilization system according to any one of claims 1 to 5, characterized in that: Including steps: The polyolefin elastomer solution is introduced into a horizontal twin-shaft kneading devolatilizer through a high-temperature atomizer for flash pre-devolatilization, and then conveyed to a twin-screw extruder devolatilizer through a discharge screw for secondary devolatilization to obtain a polymer product with low volatile content.

7. The method for devolatilizing a polyolefin elastomer solution according to claim 6, wherein: The liquid level of the polyolefin elastomer solution in the horizontal biaxial kneading devolatilizer is 25% to 50%.

8. The method for devolatilizing a polyolefin elastomer solution according to claim 6, wherein: The polyolefin elastomer solution is operated in a horizontal biaxial kneading devolatilizer at an absolute pressure of 2 to 20 kPa, a devolatilization temperature of 110 to 200° C., and a residence time of 5 to 30 minutes; The operating absolute pressure of the polyolefin elastomer solution in the twin-screw extruder devolatilizer is 0.1-5 kPa, the devolatilization temperature is 110-200° C., and the residence time is 5-10 minutes.

9. The method for devolatilizing a polyolefin elastomer solution according to claim 6, wherein: The polyolefin elastomer includes any one or more of ethylene-α-olefin random copolymer elastomer, block copolymer elastomer, EPDM rubber, EPDM rubber, and metallocene EPDM rubber.

10. The method for devolatilizing a polyolefin elastomer solution according to claim 6, wherein: The volatile content of the low-volatile content polymer product is below 100 ppm.

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