Polymerization method of nickel-based cis-butane and its application

Abstract

The present invention relates to a butadiene polymerization process and discloses a nickel-based butadiene polymerization method and its application. The nickel-based butadiene polymerization method of the present invention comprises continuously introducing a rare earth catalyst into a polymerization reaction system under solution polymerization reaction conditions of the nickel-based butadiene, and is characterized in that the feed flow rate of the rare earth catalyst is adjusted according to the measured amount of unreacted monomer in the reactor. The nickel-based butadiene polymerization method of the present invention can accurately and effectively control the monomer conversion rate of the polymerization reaction, thereby improving the stability of the polymerization reaction and reducing the cost of recycling and treatment, and has great industrial application prospects.

Description

Technical Field

[0001] The present invention relates to a butadiene polymerization process, in particular to a nickel-based butadiene polymerization method and application thereof. Background Art

[0002] Polybutadiene rubber (PB) boasts high elasticity, excellent wear resistance, and excellent resistance to heat, aging, and flexing, with low heat buildup and minimal hysteresis loss. Furthermore, the raw material is abundant and inexpensive, making it particularly suitable for tire manufacturing. Since 1960, when American companies pioneered the industrialized production of PB using a chrysene-based catalyst and solution polymerization, production has rapidly expanded with the development of the petrochemical industry, fueled by the tire manufacturing industry. By 1964, PB production capacity had leapt to second place among the seven major general-purpose synthetic rubbers, second only to styrene-butadiene rubber. Currently, industrial production facilities exist in numerous countries and regions worldwide.

[0003] In 1958, Matsumoto Takeshi and others first discovered that reduced nickel supported on an acidic substance could initiate butadiene polymerization. This marked the beginning of nickel-based directional polymerization of butadiene. Around 1965, Japan and other countries first employed a ternary nickel system consisting of nickel naphthenate, triethylaluminum, and boron trifluoride etherate complex to initiate butadiene polymerization using toluene as a solvent, achieving industrialization. In the early 1970s, my country also achieved industrialization of nickel-based butadiene rubber using a ternary nickel system consisting of nickel naphthenate, triisobutylaluminum, and boron trifluoride etherate complex using hydrogenated gasoline as a solvent. This system involved aging nickel and aluminum, followed by the addition of dilute boron.

[0004] Polymerization technology is the core of NiBR production, with conversion efficiency crucial to the product's energy and material consumption, as well as the production capacity of the equipment. Nickel-based butadiene rubber (NiBR) production technology has been industrialized in my country for over 40 years, with significant progress achieved across all aspects. However, the butadiene conversion rate has typically remained at 80-85%, failing to achieve complete conversion. Unconverted butadiene must be distilled back into the polymerization reactor to re-enter the reaction. This presents two challenges: first, the returned butadiene often contains impurities, which can affect polymerization stability; second, the distillation process consumes significant energy. Therefore, achieving complete butadiene conversion could avoid these issues. Summary of the Invention

[0005] The purpose of the present invention is to overcome the above-mentioned defects of the prior art and provide a nickel-based butadiene polymerization method and its application. The method can accurately and effectively control the monomer conversion rate of the polymerization reaction, thereby improving the stability of the polymerization reaction and reducing the cost of recycling and treatment, and has great industrial application prospects.

[0006] After in-depth research, the inventors of the present invention discovered that by real-time monitoring of the monomer conversion rate and the feed flow rate of the rare earth catalyst during the polymerization process, the monomer conversion rate of the polymerization reaction can be accurately and effectively controlled, thereby improving the stability of the polymerization reaction and reducing the cost of recycling and processing, which has great industrial application prospects. The present invention was thus completed.

[0007] The present invention provides a nickel-based cis-butane polymerization method, which comprises continuously introducing a rare earth catalyst into a polymerization reaction system under solution polymerization reaction conditions of nickel-based cis-butane, wherein the feed flow rate of the rare earth catalyst is adjusted according to the measured amount of unreacted monomers in the reactor.

[0008] The feed flow rate F of the rare earth catalyst t Satisfies the following formula,

[0009] F t =F0+F0(1-X2) / (X2-X1)

[0010] Among them, F t is the feed flow rate at time t, in mol / h;

[0011] F0 is the feed flow rate at time t0, in mol / h;

[0012] X1 is the monomer conversion rate of the polymerization solution when it enters the polymerization kettle at time t;

[0013] X2 is the monomer conversion rate of the polymerization solution when it flows out of the polymerization kettle at time t,

[0014] Furthermore, the time interval from t0 to t is greater than 0.5 hours.

[0015] Preferably, F0=M0(1-X0)C cat ,

[0016] Wherein, M0 is the initial unpolymerized monomer flow rate, in mol / h;

[0017] X0 is the monomer conversion rate of the polymerization solution when it enters the polymerization kettle at time t0;

[0018] C cat The amount of catalyst required for complete conversion of the monomer.

[0019] Preferably, the time interval from t0 to t is less than 6 hours.

[0020] Preferably, the time interval from t0 to t is more than 1 hour.

[0021] Preferably, the time interval from t0 to t is 1.5-2.5 hours.

[0022] Preferably, the rare earth catalyst is selected from one or more of a neodymium neodecanoate catalytic system, a neodymium isooctanoate catalytic system, a neodymium sulfonate catalytic system, a neodymium phosphonate catalytic system and a neodymium isopropoxide catalytic system.

[0023] Preferably, the solution polymerization reaction conditions include: reaction temperature of 0-200° C., reaction pressure of 0-11 MPa, and reaction time of 0-10 hours.

[0024] Preferably, the solution polymerization reaction conditions include: reaction temperature of 20-80° C., reaction pressure of 0-0.6 MPa, and reaction time of 1-5 hours.

[0025] Preferably, the monomer conversion rate and the feed flow rate of the rare earth catalyst during the polymerization process are monitored in real time.

[0026] The present invention also provides application of the nickel-based butadiene polymerization method of the present invention in preparing nickel-based butadiene rubber.

[0027] According to the nickel-based butadiene polymerization method of the present invention, the method can accurately and effectively control the monomer conversion rate of the polymerization reaction, thereby improving the stability of the polymerization reaction and reducing the cost of recycling and processing, and has great industrial application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0029] Figure 1 It is a structural schematic diagram of the polymerization reaction device provided by the present invention.

[0030] Description of Reference Numerals

[0031] 1-reactor; 2-agitator; 3-material inlet; 4-feed flow regulating valve; 5-control unit; 6-polymerization solution inlet pipeline; 7-polymerization solution outlet pipeline; 8-first conversion rate measurement unit; 9-second conversion rate measurement unit. DETAILED DESCRIPTION

[0032] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0033] The present invention provides a nickel-based cis-butane polymerization method, which comprises continuously introducing a rare earth catalyst into a polymerization reaction system under solution polymerization reaction conditions of nickel-based cis-butane, wherein the feed flow rate of the rare earth catalyst is adjusted according to the measured amount of unreacted monomers in the reactor.

[0034] The feed flow rate F of the rare earth catalyst t Satisfies the following formula,

[0035] F t =F0+F0(1-X2) / (X2-X1)

[0036] Among them, F t is the feed flow rate at time t, in mol / h;

[0037] F0 is the feed flow rate at time t0, in mol / h;

[0038] X1 is the monomer conversion rate of the polymerization solution when it enters the polymerization kettle at time t;

[0039] X2 is the monomer conversion rate of the polymerization solution when it flows out of the polymerization kettle at time t,

[0040] Furthermore, the time interval from t0 to t is greater than 0.5 hours.

[0041] According to the present invention, the units of t1 and t0 are both hours.

[0042] In addition, it should be noted that as the polymerization reaction proceeds, the time points represented by t0 and t1 will also change. For example, when the time interval from t0 to t1 is 0.1 hour and t0 represents 0s, t1 represents 0.1 hour; when t0 represents 0.1 hour, t1 represents 0.2 hour; when t0 represents 0.2 hour, t1 represents 0.3 hour; and so on.

[0043] According to the present invention, the time interval between t0 and t1 is greater than 0.5 hours; preferably, the time interval between t0 and t2 is greater than 1 hour; more preferably, the time interval between t0 and t3 is less than 6 hours; and further preferably, the time interval between t0 and t4 is 1.5-2.5 hours. If the time interval is less than 0.5 hours, the product may be unqualified; if the time interval is greater than 6 hours, it may cause system response delays, thereby resulting in incomplete monomer conversion.

[0044] According to the present invention, in order to more effectively adjust the feed flow rate of the rare earth catalyst according to the measured amount of unreacted monomers in the reactor, preferably, the monomer conversion rate and the feed flow rate of the rare earth catalyst during the polymerization process are monitored in real time.

[0045] According to the present invention, the amount of rare earth catalyst required for complete conversion of the monomers introduced into the reactor at time t can be calculated by using the monomer conversion rates measured at each inlet and outlet according to the above method and the above formula. Preferably, for ease of operation and control, the polymerization reaction is carried out in a polymerization reaction apparatus. The polymerization reaction apparatus will be described in detail below.

[0046] According to the present invention, in order to save catalyst, if the first adjustment X2 reaches 100%, the F should be reduced by D% every time interval t. t , until X2 is lower than 100%, and then operate according to the method of requirement 1, where the range of D is 0-99.

[0047] According to the present invention, the initial feed flow rate of the rare earth catalyst can be calculated by the following formula: F0 = M0 (1-X0) C cat ,

[0048] Wherein, M0 is the initial unpolymerized monomer flow rate, in mol / h;

[0049] X0 is the monomer conversion rate of the polymerization solution when it enters the polymerization kettle at time t0;

[0050] C cat The amount of catalyst required for complete conversion of the monomer.

[0051] C cat It can be obtained through intermittent small-scale experiments. Specifically, C cat The amount of catalyst required to completely convert a unit amount of monomer can be obtained through intermittent small-scale experiments. cat It has no units and is a ratio, which is the number of moles of catalyst / the number of moles of monomer.

[0052] The conditions of the intermittent pilot test are preferably the same as those of the nickel-based cis-butane polymerization method of the present invention. As described later, the reaction temperature can be, for example, 0-200°C, preferably 20-80°C; the reaction pressure can be, for example, 0-11 MPa, preferably 0-0.6 MPa; and the reaction time can be, for example, 0-10 hours, preferably 1-5 hours. By making the conditions of the intermittent pilot test the same as those of the nickel-based cis-butane polymerization method of the present invention, the monomer conversion rate of the polymerization reaction can be more accurately and effectively controlled.

[0053] Those skilled in the art will appreciate that in order for the monomers to undergo polymerization, the reaction system must contain a catalyst. The catalyst can be any catalyst capable of initiating polymerization of the monomers, for example, a rare earth catalyst. It is well known to those skilled in the art that rare earth catalysts typically contain a neodymium carboxylate compound, an alkyl aluminum compound, a halogen-containing compound, and a conjugated diene.

[0054] The neodymium carboxylate compound in the rare earth catalyst is C1-C 20 Neodymium carboxylate, which may be neodymium naphthenate or branched alkyl neodymium carboxylate, preferably neodymium naphthenate, neodymium isooctanoate, or neodymium neodecanoate.

[0055] The alkyl aluminum compound in the rare earth catalyst is a compound having the general formula AlR3 or AlHR2, or a mixture thereof, wherein R is a C1-C6 alkyl group, preferably tributyl aluminum, dibutyl aluminum hydride, or a mixture thereof.

[0056] The halogen-containing compound in the rare earth catalyst is an alkyl aluminum halide having the general formula AlR2X or an alkyl aluminum sesquialkyl having the general formula Al2R3X3, wherein R is a C1-C6 alkyl group and X is bromine or chlorine. Preferably, the compound is diethylaluminum monochloride, ethylaluminum sesquichloride, diisobutylaluminum monochloride, or a mixture thereof.

[0057] The conjugated diene in the rare earth catalyst is any monomer having a conjugated double bond in its molecule. Preferably, it is butadiene or isoprene or a mixture thereof. The conjugated diene in the catalyst may be the same as or different from the conjugated diene used as the polymerization monomer.

[0058] The rare earth catalyst is prepared as follows: a neodymium carboxylate compound and a conjugated diene are first mixed in an organic solvent, an alkyl aluminum compound is then added and aged, and finally a halogen-containing compound is added and aged at 0-35°C to produce a homogeneous transparent catalyst. The molar ratio of the catalyst components is: neodymium carboxylate compound: alkyl aluminum compound: halogen-containing compound: conjugated diene = 1:5-20:1-5:8-30.

[0059] There is no particular limitation on the organic solvent used in the preparation process of the rare earth catalyst of the present invention. Saturated aliphatic hydrocarbons or alicyclic hydrocarbon solvents that are inert to the reaction components and commonly used in the art can be selected. C5-C 10 Alkanes or cycloalkanes, such as pentane, isopentane, hexane, cyclohexane, heptane, octane, etc. or mixtures thereof.

[0060] According to the present invention, the polymerization reaction conditions can adopt conventional polymerization reaction conditions in the art. However, preferably, in order to overcome oxygen inhibition and obtain a polymer product with a larger molecular weight, the polymerization reaction is preferably carried out in an inert atmosphere. The inert atmosphere refers to any gas or gas mixture that does not chemically react with the reactants and products, such as nitrogen and one or more of the gases in Group 0 of the periodic table. The polymerization reaction conditions can generally include reaction temperature, reaction pressure, and reaction time. The reaction temperature can be, for example, 0-200°C, preferably 20-80°C; the reaction pressure can be, for example, 0-11 MPa, preferably 0-0.6 MPa; and the reaction time can be, for example, 0-10 hours, preferably 1-5 hours.

[0061] In a preferred embodiment of the present invention, the nickel-based butadiene polymerization method of the present invention uses Figure 1 The polymerization reaction apparatus shown is carried out as Figure 1 As shown, the device includes a reactor 1 and a control unit 5, wherein the reactor 1 includes a reactor body provided with a rare earth catalyst inlet, a material inlet, and a material outlet, and a jacket provided with an inlet and an outlet surrounding the reactor body; a first conversion rate measuring unit 8 for measuring the conversion rate of the inlet monomer is provided on a pipeline 6 connecting the material inlet and the material source; a second conversion rate measuring unit 9 for measuring the monomer conversion rate is provided on a pipeline 7 connecting the material outlet and the outside; a catalyst flow rate measuring control unit 4 is provided on a pipeline 3 connecting the rare earth catalyst inlet and the rare earth catalyst source; the first conversion rate measuring unit 8, the second conversion rate measuring unit 9, and the catalyst flow rate measuring control unit 4 are respectively connected to the control unit 5; the polymer preparation method includes continuously introducing a monomer solution into the reactor 1 through the material inlet under monomer solution polymerization reaction conditions, polymerizing the monomer solution, and then discharging the monomer solution from the material outlet; the control unit 5 adjusts the feed flow rate of the rare earth catalyst based on the catalyst increment required for the unreacted monomer calculated based on the received data obtained from the conversion rate measurements of the individual monomers.

[0062] Correspondingly, F0 is the monomer conversion rate X0 of the polymerization solution entering the polymerization kettle at time t0, the initial unpolymerized monomer flow rate M0, and the catalyst dosage C required for complete conversion of the monomers, respectively measured by the first conversion rate measurement unit 8. cat The calculated catalyst feed flow rate at time t0; F t The catalyst feed flow rate at time t is calculated as the monomer conversion rate X1 of the polymerization solution when entering the polymerization kettle at time t measured by the first conversion rate measurement unit 8, the monomer conversion rate X2 of the polymerization solution when flowing out of the polymerization kettle at time t measured by the second conversion rate measurement unit 9, and the catalyst feed flow rate F0 at time t0.

[0063] According to the present invention, the method of adjusting the feed flow rate of the gaseous olefin monomer by calculating the catalyst feed flow rate based on the data measured by each monomer conversion measurement unit and the flow measurement unit received by the control unit 5 is well known to those skilled in the art. For example, F can be calculated based on the conversion rate and flow rate measured by each monomer conversion measurement unit and the flow measurement unit in combination with the above formula. t The catalyst feed amount can be manually calculated according to the above method, and the feed flow rate can be manually adjusted according to the calculated polymerization heat; the catalyst feed amount can also be calculated by computer, and the feed flow rate can be automatically adjusted by computer control.

[0064] As the first conversion rate measuring unit 8 and the second conversion rate measuring unit 9, for example, an online gas chromatograph can be used.

[0065] According to the present invention, in order to mix the materials in the kettle more evenly and obtain a polymer product with better performance, preferably, the polymerization reaction device further includes a stirrer 2 disposed in the kettle.

[0066] The present invention also provides application of the nickel-based butadiene polymerization method of the present invention in preparing nickel-based butadiene rubber.

[0067] The present invention will be described in detail below through examples, but the present invention is not limited to the following examples.

[0068] Catalyst preparation example

[0069] Under nitrogen protection, 470.5 g of hexane, 39 ml of 0.50 mol / L neodymium neodecanoate solution and 21.0 g of butadiene were added to a clean and dry aging kettle. After mixing, 183 ml of 2.0 mol / L diisobutylaluminum monohydrogen solution was added at 50° C. and stirred for reaction for 30 minutes. Then, the reactor was cooled to 30° C., and 24.6 ml of 2.0 mol / L diethylaluminum monochloride solution was added. The aging was continued for 24 hours for polymerization. The catalyst was in a yellow-green transparent homogeneous state.

[0070] Example 1

[0071] exist Figure 1The preparation of olefin polymers is carried out in the polymerization reaction apparatus shown, wherein the reactor has a capacity of 2L. The reactor is controlled to a temperature of 50°C and a pressure of 0.4 MPa by a jacket. The catalyst is introduced into the reactor 1 through a pipeline 3. A nickel-based polymerization solution (polybutadiene, nickel-based catalyst, butadiene monomer mixture, monomer conversion rate of 82%) is continuously introduced into the reactor 1 through a material inlet and polymerized (at a rate of 0.6 kg / h). After that, polymerization is initiated. From the start of the polymerization reaction, every 2 hours, a control unit 5 (specifically, a computer DCS system, the same applies hereinafter) calculates the reaction mixture according to the data received from each monomer conversion measurement unit and according to the formula F of the present invention. t =F0+F0(1-X2) / (X2-X1) The amount of catalyst required for complete conversion of the nickel-based polymer solution is calculated to control the feed flow regulating valve 4 to adjust the feed flow of the catalyst, wherein the initial feed flow F0 of the rare earth catalyst is calculated according to the formula of the present invention: F0=M0(1-X0)C cat Calculated, C cat This was obtained by conducting a batch test experiment under the same polymerization conditions as in the example. After 6 hours of polymerization, the solution containing butadiene rubber was removed from the material outlet and filtered. The filter residue was washed three times with 100 mL of ethanol and 200 mL of water, and then dried in an oven at a temperature of 50°C and a pressure of -0.1 MPa (gauge pressure) to obtain butadiene rubber. The average conversion rate over 6-9 hours was 99%.

[0072] Example 2

[0073] This example illustrates the preparation of an olefin polymer according to the present invention.

[0074] exist Figure 1 The preparation of olefin polymers is carried out in the polymerization reaction apparatus shown, wherein the reactor has a capacity of 2 L. The reactor temperature is controlled at 50° C. and the pressure is set to 0.4 MPa via a jacket. The catalyst is introduced into the reactor 1 via pipeline 3. A nickel-based polymerization solution (polybutadiene, nickel-based catalyst, butadiene monomer mixture, monomer conversion rate of 71%) is continuously introduced into the reactor 1 via the material inlet and polymerized (at a rate of 0.7 kg / h). After that, polymerization is initiated. From the start of the polymerization reaction, the control unit 5 calculates the reaction mixture every 1.5 hours based on the data received from the various monomer conversion measurement units and according to the formula F of the present invention. t =F0+F0(1-X2) / (X2-X1) The amount of catalyst required for complete conversion of the nickel-based polymer solution is calculated to control the feed flow regulating valve 4 to adjust the feed flow of the catalyst, wherein the initial feed flow F0 of the rare earth catalyst is calculated according to the formula of the present invention: F0=M0(1-X0)C cat Calculated, C catThis was obtained by conducting a batch test experiment under the same polymerization conditions as in the example. After 6 hours of polymerization, the solution containing butadiene rubber was removed from the material outlet and filtered. The filter residue was washed three times with 100 mL of ethanol and 200 mL of water, and then dried in an oven at a temperature of 50°C and a pressure of -0.1 MPa (gauge pressure) to obtain butadiene rubber. The average conversion rate over 6-9 hours was 100%.

[0075] Example 3

[0076] This example illustrates the preparation of an olefin polymer according to the present invention.

[0077] exist Figure 1 The preparation of olefin polymers is carried out in the polymerization reaction apparatus shown, wherein the reactor has a capacity of 2 L. The reactor temperature is controlled at 50° C. and the pressure is set to 0.4 MPa via a jacket. The catalyst is introduced into the reactor 1 via pipeline 3. A nickel-based polymerization solution (polybutadiene, nickel-based catalyst, butadiene monomer mixture, monomer conversion rate of 79%) is continuously introduced into the reactor 1 via the material inlet and polymerized (at a rate of 0.65 kg / h). After that, polymerization is initiated. From the start of the polymerization reaction, the control unit 5 calculates the reaction mixture every 2.5 hours based on the data received from the various monomer conversion measurement units and according to the formula F of the present invention. t =F0+F0(1-X2) / (X2-X1) The amount of catalyst required for complete conversion of the nickel-based polymer solution is calculated to control the feed flow regulating valve 4 to adjust the feed flow of the catalyst, wherein the initial feed flow F0 of the rare earth catalyst is calculated according to the formula of the present invention: F0=M0(1-X0)C cat Calculated, C cat This was obtained by conducting a batch test experiment under the same polymerization conditions as in the example. After 6 hours of polymerization, the solution containing butadiene rubber was removed from the material outlet and filtered. The filter residue was washed three times with 100 mL of ethanol and 200 mL of water, and then dried in an oven at a temperature of 50°C and a pressure of -0.1 MPa (gauge pressure) to obtain butadiene rubber. The average conversion rate over 6-9 hours was 98%.

[0078] Example 4

[0079] This example illustrates the preparation of an olefin polymer according to the present invention.

[0080] exist Figure 1The preparation of olefin polymers is carried out in the polymerization reaction apparatus shown, wherein the reactor has a capacity of 2 L. The reactor temperature is controlled at 50° C. and the pressure is set to 0.4 MPa via a jacket. The catalyst is introduced into the reactor 1 via pipeline 3. A nickel-based polymerization solution (polybutadiene, nickel-based catalyst, butadiene monomer mixture, monomer conversion rate of 71%) is continuously introduced into the reactor 1 via the material inlet and polymerized (at a rate of 0.7 kg / h). After that, polymerization is initiated. From the start of the polymerization reaction, the control unit 5 calculates the reaction mixture every 3.5 hours based on the data received from the various monomer conversion measurement units and according to the formula F of the present invention. t =F0+F0(1-X2) / (X2-X1) The amount of catalyst required for complete conversion of the nickel-based polymer solution is calculated to control the feed flow regulating valve 4 to adjust the feed flow of the catalyst, wherein the initial feed flow F0 of the rare earth catalyst is calculated according to the formula of the present invention: F0=M0(1-X0)C cat Calculated, C cat This was obtained by conducting a batch test experiment under the same polymerization conditions as in the example. After 6 hours of polymerization, the solution containing butadiene rubber was removed from the material outlet and filtered. The filter residue was washed three times with 100 mL of ethanol and 200 mL of water, and then dried in an oven at a temperature of 50°C and a pressure of -0.1 MPa (gauge pressure) to obtain butadiene rubber. The average conversion rate over 6-9 hours was 93%.

[0081] Example 5

[0082] exist Figure 1 The preparation of olefin polymers is carried out in the polymerization reaction apparatus shown, wherein the reactor has a capacity of 2L. The reactor temperature is controlled at 50°C and the pressure is set to 0.4MPa via a jacket. The catalyst is introduced into the reactor 1 via pipeline 3. A nickel-based polymerization solution (polybutadiene, nickel-based catalyst, butadiene monomer mixture, monomer conversion rate of 76%) is continuously introduced into the reactor 1 via the material inlet and polymerized (at a rate of 0.7kg / h). After that, polymerization is initiated. From the start of the polymerization reaction, the control unit 5 calculates the reaction mixture every 1 hour based on the data received from the various monomer conversion measurement units and according to the formula F of the present invention. t =F0+F0(1-X2) / (X2-X1) The amount of catalyst required for complete conversion of the nickel-based polymer solution is calculated to control the feed flow regulating valve 4 to adjust the feed flow of the catalyst, wherein the initial feed flow F0 of the rare earth catalyst is calculated according to the formula of the present invention: F0=M0(1-X0)C cat Calculated, C catThis was obtained by conducting a batch test experiment under the same polymerization conditions as in the example. After 6 hours of polymerization, the solution containing butadiene rubber was removed from the material outlet and filtered. The filter residue was washed three times with 100 mL of ethanol and 200 mL of water, and then dried in an oven at a temperature of 50°C and a pressure of -0.1 MPa (gauge pressure) to obtain butadiene rubber. The average conversion rate over 6-9 hours was 90%.

[0083] Comparative Example 1

[0084] This comparative example illustrates the reference preparation of an olefin polymer.

[0085] Olefin polymers were prepared according to the method of Example 1, except that the catalyst flow rate (calculated based on an inlet monomer conversion of 82%) was kept constant and the feed rate of gaseous olefin monomers was not adjusted. The average conversion rate over 6-9 hours was 89%.

[0086] Comparative Example 2

[0087] This comparative example illustrates the reference preparation of an olefin polymer.

[0088] Olefin polymers were prepared according to the method of Example 1, except that, every 0.5 h, control unit 5 controlled feed flow regulating valve 4 to adjust the catalyst feed flow rate based on the amount of catalyst required for complete conversion of the nickel-based polymerization solution, calculated from data received from the monomer conversion measurement units. The average conversion rate for 6-9 hours was 100%. However, the amount of catalyst added was too high, resulting in a product with a substandard Mooney standard.

[0089] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A nickel-based butadiene polymerization method, comprising continuously introducing a rare earth catalyst into a polymerization reaction system under solution polymerization reaction conditions of nickel-based butadiene, characterized in that: The feed flow rate of the rare earth catalyst is adjusted according to the measured amount of unreacted monomers in the reactor, The feed flow rate F of the rare earth catalyst t Satisfies the following formula, F t =F0+F0(1-X2) / (X2-X1) Among them, F t is the feed flow rate at time t, in mol / h; F0 is the feed flow rate at time t0, in mol / h; X1 is the monomer conversion rate of the polymerization solution when it enters the polymerization kettle at time t; X2 is the monomer conversion rate of the polymerization solution when it flows out of the polymerization kettle at time t, And, the time interval from t0 to t is greater than 0.5 hours, Where, F0=M0(1-X0)C cat , Wherein, M0 is the initial unpolymerized monomer flow rate, in mol / h; X0 is the monomer conversion rate of the polymerization solution when it enters the polymerization kettle at time t0; C cat The amount of catalyst required for complete conversion of the monomer.

2. The method according to claim 1, wherein The time interval from t0 to t is less than 6 hours.

3. The method according to claim 1 or 2, wherein: The time interval from t0 to t is more than 1 hour.

4. The method according to claim 3, wherein: The time interval from t0 to t is 1.5-2.5 hours.

5. The method according to claim 1 or 2, wherein: The rare earth catalyst is selected from one or more of a neodymium neodecanoate catalytic system, a neodymium isooctanoate catalytic system, a neodymium sulfonate catalytic system, a neodymium phosphonate catalytic system and a neodymium isopropoxide catalytic system.

6. The method according to claim 1 or 2, wherein: The solution polymerization reaction conditions include: reaction temperature of 20-200° C., reaction pressure of 0-11 MPa, and reaction time of 1-10 hours.

7. The method according to claim 6, wherein: The solution polymerization reaction conditions include: reaction temperature of 20-80° C., reaction pressure of 0-0.6 MPa, and reaction time of 1-5 hours.

8. The method according to claim 1 or 2, wherein: The monomer conversion rate and feed flow rate of the rare earth catalyst during the polymerization process were monitored in real time.

9. Use of the method according to any one of claims 1 to 8 in the preparation of nickel-based butadiene rubber.

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