Method for producing elastomeric polymer in supercritical states

Abstract

FIELD: polymer production.SUBSTANCE: invention relates to the polymerization of an elastomeric polymer under supercritical conditions. A method for producing an elastomer is proposed, comprising the following steps: introducing an organic solvent, a monomer, a cocatalyst and a base catalyst into a reactor under anhydrous and oxygen-free conditions, wherein the materials undergo a polymerization reaction in the reactor in a mode in which the reaction temperature exceeds the supercritical temperature of the system, and the reaction pressure exceeds the supercritical pressure of the system, in order to obtain an elastomer; wherein the monomer is one or more of linear or branched α-olefins comprising 3-20 carbon atoms and ethylene, where the reaction temperature is from 135 to 220 °C, and the reaction pressure is from 2 to 10 MPa.EFFECT: creating a method for producing an elastomer, which is configured to eliminate the disadvantages of difficult solvent separation, high viscosity of the polymer solution and low polymer concentration during solution polymerization.5 cl, 3 tbl, 4 ex

Description

FIELD OF TECHNOLOGY TO WHICH THE INVENTION RELATES

[0001] The present invention relates to the field of polymeric materials, in particular, to a method for producing an elastomeric polymer (hereinafter referred to as an elastomer). BACKGROUND OF THE INVENTION

[0002] Elastomer belongs to a class of polymer materials with high elasticity and reversible deformation ability, and is widely used in the fields of rubber products, sealing materials, damping materials, medical materials and so on. At present, the industrial production of elastomers includes the gas-phase method, suspension method and solution method (Prog. Polym. Sci. 2001, 26, 1287-1336). Compared with the first two methods, the solution method has such advantages as small volume of polymerization reactor, short polymerization time, convenient change of product quality level, high single-pass ethylene conversion rate, precise control of product molecular weight and uniform distribution of copolymer composition (Synthetic Resins and Plastics. 2010, 27(2), 64-68).Therefore, the solution polymerization process is widely used in the production of elastomers, including ethylene / α-olefin copolymers, ethylene-propylene rubber (EPR, EPDM (ethylene-propylene-diene monomer copolymer rubber)), propylene-based elastomers, ethylene-based elastomers and the like. However, the solution polymerization process also has some disadvantages. For example, the solution polymerization of olefins consumes a large amount of organic solvent, the energy consumption for solvent separation and regeneration is significant, and the cost is high. In addition, in the solution polymerization process, as the polymer concentration increases, the viscosity of the solution increases and the resistance to mass transfer and heat dissipation increases, and there is a tendency for sediment to form inside the reactor or even clog the pipeline; therefore, the polymer concentration in the solution polymerization process is generally low.

[0003] Supercritical polymerization, by utilizing the unique physical properties of supercritical fluids, can significantly reduce the viscosity of conventional solution polymerization systems and eliminate mass transfer and heat dissipation difficulties at high concentrations, thereby promoting polymerization and increasing productivity and equipment utilization. The process also facilitates the separation of polymers from solvents, reduces energy consumption for solvent separation and recovery, and effectively reduces production costs.

[0004] However, the high-pressure equipment required to maintain the supercritical state during the supercritical polymerization process is expensive, and the initial capital investment and the costs of maintaining and operating the reactor and support systems (such as compressors and high-pressure sealing devices) are significantly higher. At the same time, the supercritical process places more stringent and complex demands on catalysts, requiring a catalyst system that is more resistant to high temperatures and high pressures. SUMMARY OF THE INVENTION

[0005] In view of this, the aim of the present invention is to create a method for producing an elastomer that overcomes the disadvantages of difficult solvent separation, high polymer solution viscosity, and low polymer concentration during solution polymerization. Furthermore, the resulting supercritical system, in the presence of hexane and monomers, is capable of polymerization under supercritical conditions at relatively low temperatures and pressures, thereby reducing production costs of the supercritical process and increasing throughput.

[0006] The present invention provides a method for producing an elastomer, including the following steps: introducing an organic solvent, a monomer, a cocatalyst and a base catalyst into a reactor under anhydrous and oxygen-free conditions, wherein the materials undergo a polymerization reaction in the reactor in a mode in which the reaction temperature exceeds the supercritical temperature of the system, and the reaction pressure exceeds the supercritical pressure of the system, to obtain an elastomer; wherein the monomer is one or more of linear or branched α-olefins containing 3-20 carbon atoms, and ethylene.

[0007] In a preferred embodiment, the organic solvent is a C6 alkane.

[0008] In a preferred embodiment, the monomer is one or more selected from the group consisting of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-hexadecene, 1-octadecene and 1-eicosene; and the monomer is subjected to dehydration and deoxygenation treatment before use.

[0009] In a preferred embodiment, the cocatalyst is one or more selected from the group consisting of methylaluminoxane compounds, modified methylaluminoxane compounds, tris(pentafluorophenyl)borane, triphenylcarbenium tetrakis(pentafluorophenyl)borate, N,N-dimethylaniline tetrakis(pentafluorophenyl)borate, triisobutylaluminum and trimethylaluminum.

[0010] In a preferred embodiment, the base catalyst is one or more selected from the group consisting of diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride, diphenylmethylene (cyclopentadienyl) (2-dimethylaminofluorenyl) zirconium dichloride, bis[2-(3',5'-di-tert-butylphenyl)indenyl]zirconium dichloride, dicyclopentadienyl bis(phenoxy)zirconium, ethylene bis(indenyl)bis(phenoxy)zirconium, bis(salicylidenephenylimino)titanium dichloride, [N-(3,5-di-tert-butylsalicylidene)-2-diphenylphosphinophenylimino]titanium trichloride, dimethylsilylenebis(indenyl)zirconium dichloride, dimethylsilylene(tetramethylcyclopentadienyl)(tert-butylamido)dimethyltitanium, dimethylsilylene(3-pyrrolilindenyl)(tert-butylamido)dimethyltitanium, pentamethylcyclopentadienyl(2-phenylphenoxy)titanium dichloride and pentamethylcyclopentadienyl(2,6-diisopropylphenoxy)titanium dichloride.

[0011] In a preferred embodiment, the reaction temperature is from 135 to 220°C.

[0012] In a preferred embodiment, the reaction pressure is from 2 to 10 MPa.

[0013] In a preferred embodiment, the polymerization reaction is carried out in a batch polymerization mode, a semi-continuous polymerization mode, or a continuous polymerization mode.

[0014] In a preferred embodiment, the polymerization reaction is carried out for a period of 2 minutes to 120 minutes.

[0015] In a preferred embodiment, the elastomer has a weight average molecular weight of 3,000 to 1,200,000 g / mol, a polydispersity index of 1.0 to 5.0, and a density of 0.84 to 0.93 g / cm 3 .

[0016] The present invention provides a method for producing an elastomer comprising the following steps: introducing an organic solvent, a monomer, a cocatalyst and a base catalyst into a reactor under anhydrous and oxygen-free conditions, wherein the materials undergo a polymerization reaction in the reactor in a mode in which the reaction temperature exceeds the supercritical temperature of the system, and the reaction pressure exceeds the supercritical pressure of the system, to obtain an elastomer; wherein the monomer is one or more of linear or branched α-olefins containing 3-20 carbon atoms, and ethylene.Compared with the prior art, the manufacturing method proposed by the present invention selects specific starting materials in combination with specific reaction conditions, resulting in an overall improvement in reaction performance and solving the problems of difficult solvent separation, high polymer solution viscosity, and low polymer concentration during solution polymerization. This accelerates the polymerization reaction and increases the productivity and utilization of production equipment. Furthermore, the method can effectively reduce the temperature and pressure of the supercritical polymerization solvent system, thereby reducing production costs of the supercritical process and increasing utilization. DETAILED DESCRIPTION.

[0017] The technical solutions of the present invention will be clearly and completely described below in connection with the embodiments of the present invention. It is obvious that the described embodiments constitute only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by persons skilled in the art based on the described embodiments without creative efforts shall fall within the scope of legal protection of the present invention.

[0018] The present invention provides a method for producing an elastomer comprising the following steps: introducing an organic solvent, a monomer, a cocatalyst and a base catalyst into a reactor in dehydrated and oxygen-free states, wherein the materials undergo a polymerization reaction in the reactor in a mode in which the reaction temperature exceeds the supercritical temperature of the system, and the reaction pressure exceeds the supercritical pressure of the system, to obtain an elastomer; wherein the monomer is one or more of linear or branched α-olefins containing 3-20 carbon atoms, and ethylene.

[0019] In the present invention, anhydrous and anaerobic conditions are established using techniques well known to those skilled in the art. For example, the reactor can be flushed with solvent and then filled with solvent under normal pressure. Furthermore, all materials used are subjected to dehydration and deoxygenation treatment.

[0020] In the present invention, the organic solvent is preferably a C6 alkane, more preferably n-hexane, isohexane, or cyclohexane, and most preferably n-hexane. In the present invention, the source of the organic solvent is not particularly limited, and commercially available products well known to those skilled in the art can be used.

[0021] In the present invention, the monomer is one or more linear or branched α-olefins containing 3 to 20 carbon atoms and ethylene, preferably one or more selected from the group consisting of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-hexadecene, 1-octadecene and 1-eicosene, and more preferably ethylene and 1-butene. In the present invention, the source of the organic solvent is not particularly limited, and commercially available products well known to those skilled in the art can be used. The monomer is subjected to dehydration and deoxygenation treatment before use.

[0022] In the present invention, the cocatalyst is preferably one or more selected from the group consisting of a methylaluminoxane compound, a modified methylaluminoxane compound, tris(pentafluorophenyl)borane, triphenylcarbenium tetrakis(pentafluorophenyl)borate, N,N-dimethylaniline tetrakis(pentafluorophenyl)borate, triisobutylaluminum, and trimethylaluminum. In the present invention, the source of the cocatalyst is not particularly limited, and commercially available products well known to those skilled in the art can be used.

[0023] In the present invention, the base catalyst is preferably one or more selected from the group consisting of diphenylmethylene(cyclopentadienyl)(fluorenyl)zirconium dichloride, diphenylmethylene(cyclopentadienyl)(2-dimethylaminofluorenyl)zirconium dichloride, bis[2-(3',5'-di-tert-butylphenyl)indenyl]zirconium dichloride, dicyclopentadienyl-bis(phenoxy)zirconium, ethylene-bis(indenyl)bis(phenoxy)zirconium, bis(salicylidenephenylimino)titanium dichloride, [N-(3,5-di-tert-butylsalicylidene)-2-diphenylphosphinophenylimino]titanium trichloride, dimethylsilylenebis(indenyl)zirconium dichloride, dimethylsilylene(tetramethylcyclopentadienyl)(tert-butylamido)dimethyltitanium, dimethylsilylene(3-pyrrolilindenyl)(tert-butylamido)dimethyltitanium, pentamethylcyclopentadienyl(2-phenylphenoxy)titanium dichloride and pentamethylcyclopentadienyl(2,6-diisopropylphenoxy)titanium dichloride, more preferably diphenylmethylene(cyclopentadienyl)(2-dimethylaminofluorenyl)zirconium dichloride.In the present invention, the source of the base catalyst is not particularly limited, and commercially available metallocene catalysts or non-metallocene catalysts well known to those skilled in the art can be used.

[0024] In the present invention, the amount of each of the above-mentioned raw materials is preferably set according to a specific reaction. In a preferred embodiment of the present invention, the main catalyst has a concentration of preferably 1 to 50 μmol / L, more preferably 10 to 20 μmol / L. The molar concentration ratio of the cocatalyst to the main catalyst is preferably (60 to 120): 1, more preferably (80 to 100): 1. The feed rate of ethylene is preferably 10 kg / h to 100 kg / h, more preferably 30 to 50 kg / h. The feed rate of butene is preferably 50 to 150 kg / h, more preferably 70 to 90 kg / h. The feed rate of n-hexane is preferably 100 to 300 kg / h, more preferably 170 to 190 kg / h.

[0025] In the present invention, the materials undergo a polymerization reaction in a reactor under conditions in which the reaction temperature exceeds the supercritical temperature of the system, and the reaction pressure exceeds the supercritical pressure of the system; wherein the reaction temperature is preferably from 135 to 220°C, more preferably from 183 to 187°C, and the reaction pressure is preferably from 2 to 10 MPa, more preferably from 5 to 7 MPa.

[0026] In the present invention, the reaction temperature, i.e., the polymerization temperature, should be higher than the supercritical temperature of the polymerization system, and the reaction pressure, i.e., the polymerization pressure, should also be higher than the supercritical pressure of the polymerization system. This is the fundamental idea for solving the technical problems of the present invention.

[0027] In the present invention, the polymerization reaction is preferably carried out in a batch polymerization mode, a semi-continuous polymerization mode, or a continuous polymerization mode. When a batch or semi-continuous polymerization process is adopted, the organic solvent, monomers, cocatalyst, and main catalyst can be introduced into the reactor sequentially or simultaneously, but they are preferably introduced sequentially. When a continuous polymerization process is adopted, the organic solvent, monomers, cocatalyst, and main catalyst must be introduced into the reactor continuously and simultaneously. Based on this, the present invention is applicable to various polymerization reaction conditions and has wide application prospects.

[0028] In a preferred embodiment of the present invention, the polymerization reaction process is specifically as follows.

[0029] The circulating purification system is started to purify n-hexane, ethylene, and 1-butene to ensure the feedstock is dehydrated and anaerobic. The mixed material feed line is opened, and the mixed materials are heated to a temperature of 130 to 150°C and then introduced into the reactor. The reactor temperature is increased, and the reaction pressure is adjusted to meet the above requirements. The main catalyst and cocatalyst feed line is opened, the main catalyst and cocatalyst are introduced, and the screw extruder is started to extrude and pelletize the polymer. After a significant increase in temperature is observed, the temperature of the mixed materials is gradually reduced to room temperature until the reaction becomes stable. The reaction temperature is maintained within the above range, and the materials undergo polymerization in the reactor, producing a polymer product.

[0030] In the present invention, the polymerization reaction is preferably carried out for a period of 2 min to 120 min.

[0031] The present invention provides a method for producing an elastomer by supercritical polymerization, wherein the produced elastomer comprises, but is not limited to, an ethylene-α-olefin copolymer, a propylene-based elastomer, and an ethylene-based elastomer.

[0032] In the present invention, the elastomer has a weight average molecular weight of preferably 3,000 g / mol to 1,200,000 g / mol, more preferably 100,000 to 250,000 g / mol; a polydispersity index of preferably 1.0 to 5.0, more preferably 2.0 to 3.0; and a density of preferably 0.84 to 0.93 g / cm 3 , more preferably from 0.85 to 0.90 g / cm 3 .

[0033] The present invention provides a method for producing an elastomer. A C6 alkane solvent, monomers, a cocatalyst, and a base catalyst are introduced into a reactor in an anhydrous and anaerobic state. The reaction temperature and pressure are set above the supercritical temperature and supercritical pressure of the C6 alkane solvent. The concentration of the fed monomers ranges from 0.1 to 20 mol / L. The residence time of all materials in the reactor is controlled within the range of 2 to 120 min. Under catalytic conditions using the base catalyst and cocatalyst, the monomers polymerize in a supercritical fluid. This effectively reduces the viscosity of the polymerization system, significantly improves production efficiency, facilitates the separation of the polymer from the solvent, and reduces energy consumption for solvent separation and regeneration.

[0034] The present invention provides a method for producing an elastomer comprising the following steps: introducing an organic solvent, a monomer, a cocatalyst and a base catalyst into a reactor under anhydrous and oxygen-free conditions, wherein the materials undergo a polymerization reaction in the reactor in a mode in which the reaction temperature exceeds the supercritical temperature of the system, and the reaction pressure exceeds the supercritical pressure of the system, to obtain an elastomer; wherein the monomer is one or more of linear or branched α-olefins containing 3-20 carbon atoms and ethylene.Compared with the prior art, the manufacturing method proposed by the present invention selects specific starting materials in combination with specific reaction conditions, resulting in an overall improvement in reaction performance and solving the problems of difficult solvent separation, high polymer solution viscosity, and low polymer concentration during solution polymerization. This method accelerates the polymerization reaction and increases the polymerization yield. Furthermore, the method can effectively reduce the temperature and pressure of the supercritical polymerization solvent system, thereby reducing the production costs of the supercritical process.

[0035] To further illustrate the present invention, the following embodiments are described in detail. In the present invention, the feed molar concentration refers to the initial monomer concentration upon entering the reactor, calculated based on the volume of alkane solvent; the feed molar ratio refers to the initial ratio of the molar concentrations of monomer to comonomer upon entering the reactor. All starting materials used in the following embodiments of the present invention are commercially available.

[0036] Example 1

[0037] In this experiment, diphenylmethylene(cyclopentadienyl)(2-dimethylaminofluorenyl)zirconium dichloride was used as the base catalyst, methylaluminoxane as the cocatalyst, n-hexane as the organic solvent, and 1-butene as the comonomer. 1-Butene was liquefied and stored under a pressure of 4 atmospheres (0.405 MPa) at room temperature, and the base catalyst was dissolved in 5 ml of toluene to prepare a solution for use. Before the experiment, the reactor was flushed by displacing its contents with the solvent and then filled with the solvent under normal pressure.

[0038] The experimental procedure was as follows. A circulating purification system was started to purify n-hexane, ethylene, and 1-butene to ensure the feedstock was dehydrated and anaerobic. The mixed material feed line was opened, and the mixed materials were heated to 140°C and fed into the reactor. The reactor temperature was increased, and the reaction pressure was maintained at 6 MPa. Then, the main catalyst and cocatalyst feed line was opened, the main catalyst and cocatalyst were fed, and the screw extruder was started to extrude and pelletize the polymer. After a significant increase in temperature was observed, the temperature of the mixed materials was gradually reduced to room temperature until the reaction became stable. The reaction temperature was stabilized at 180°C, and the polymerization reaction time was 20 minutes, resulting in the polymer product.

[0039] In this experiment, the concentration of the main catalyst in the reactor was 15 μmol / L, the molar concentration ratio of the cocatalyst to the main catalyst was 91:1, and the feed rates of ethylene, butene, and n-hexane were 41 kg / h, 81 kg / h, and 178 kg / h, respectively. The mass ratio of 1-butene to ethylene in the feed was 1.97:1. All materials used in this experiment were subjected to dehydration and deoxygenation treatment.

[0040] The molecular weight (Mw and Mn) and polydispersity index (PDI) of the polymer were determined using high-temperature gel permeation chromatography (PL-GPC220). 1,2,4-trichlorobenzene was used as a solvent, and a polymer solution with a concentration of 0.1 to 0.3 wt% was prepared at 150°C. For the determination at 150°C, polystyrene standards (PS) with a narrow molecular weight distribution were used, with a solvent flow rate of 1.0 ml / min. For all PS standards, the parameter k = 5.91 × 10 -4and a=0.69. For polyethylene (PE), the parameter was k=1.21×10 -4 and a=0.707.

[0041] The melting point (Tm) of the copolymer was determined using a Mettler DSC 3+. A polymer sample weighing 8.0 to 10.0 mg was heated at a rate of 20°C / min to 120°C and held for 5 minutes to eliminate thermal history. The sample was then cooled at a rate of 10°C / min to -100°C and held for 5 minutes, after which it was reheated at a rate of 10°C / min to 120°C. The polymer melting point was obtained from the second heating curve.

[0042] The polymer density was measured using the drainage method.

[0043] The ASPEN simulation results for the saturated vapor pressure of mixed materials at different temperatures are shown in Table 1.Table 1. Vapor pressure and temperature correlation model Temperature, °C Pressure, MPa Model state Supercritical state 160,00 5,654 Everything is fine (OK) No 170,00 5,772 OK No 175,00 5,778 OK No 176,00 5,774 OK No 177,00 5,768 OK No 178,00 5,758 OK No 179,00 5,765 Errors Yes 180,00 4,967 Errors Yes 185,00 5,211 Errors Yes

[0044] The experimental results are listed below in Table 2.

[0045] Table 1 shows that when the reactor feed composition is formed from 41 kg / h of ethylene, 81 kg / h of α-olefin, and 178 kg / h of n-hexane, the mixed material system can be maintained in a completely liquid phase below the critical temperature of 178°C due to the pressure increase. When the reactor parameters are set above 179°C and 5.759 MPa, the reactor system has a temperature and pressure above the critical ones and is therefore in a supercritical state.

[0046] Example 2

[0047] The experimental conditions were the same as in Example 1, except that the reaction temperature was increased to 185°C and the reaction pressure was 6 MPa. The experimental results are shown in Table 2.

[0048] Example 3

[0049] The experimental conditions were the same as in Example 1, except that the reaction temperature was increased to 190°C and the reaction pressure was 6 MPa. The experimental results are shown in Table 2.

[0050] Comparative Example 1

[0051] The experimental conditions were the same as in Example 1, except that the reaction temperature was maintained at approximately 150°C and the reaction pressure was 6 MPa. The experimental results are shown in Table 2.

[0052] Comparative Example 2

[0053] The experimental conditions were the same as in Example 1, except that the reaction temperature was maintained at approximately 160°C and the reaction pressure was 6 MPa. The experimental results are shown in Table 2.

[0054] Comparative Example 3

[0055] The experimental conditions were the same as those in Example 1, except that the reaction temperature was maintained at about 170°C and the reaction pressure was 6 MPa. The experimental results are shown in Table 2.Table 2. Experimental results №№ Output, kg Torque, N∙cm Tm, °C Mw, 104 g / mol PDI (polydisp index) Density, g / cm3 Example 1 45,25 1000 60,25 13,20 2,31 0,869 Example 2 45,56 990 60,31 13,39 2,29 0,870 Example 3 45,36 965 60,45 13,45 2,30 0,867 Comparative example 1 45,32 1370 55,02 12,48 2,26 0,865 Comparative example 2 45,24 1325 56,11 12,50 2,29 0,866 Comparative example 3 45,01 1260 57,21 12,60 2,28 0,867

[0056] The experimental results show that, under the same yield (i.e., the same copolymer concentration in the reactor system), the stirring torque in Examples 1-3 is significantly weaker than in Comparative Examples 1-3. This indicates that polymerization in a supercritical fluid can significantly reduce the viscosity of the polymerization system. Meanwhile, other product test data are stable and meet the requirements for the finished product.

[0057] Example 4: The energy consumption of the unit operating at the reaction temperature under supercritical reaction conditions is shown in Table 3.

[0058] Comparative Example 4: The energy consumption of the unit operating at reaction temperature under non-supercritical reaction conditions is shown in Table 3.Table 3. Comparison of the effects of supercritical and non-supercritical processes on the energy consumption and performance of the flash outgassing process State of polymerization Polymerization temperature, °C Polymerization pressure, MPa Required spraying temperature, °C Heating temperature difference, °C kg of conventional fuel per ton of product, kg of conventional fuel / t Productivity and equipment utilization, % Comparative example 4 non-supercritical 150 6,0 185 35 100,76 80 Example 4 supercritical 185 6,0 185 0 11,40 100

[0059] As shown in Table 3, when the reaction temperature of the operating unit was increased from the non-supercritical reaction condition (150°C, 6.0 MPa) to the supercritical reaction condition (185°C, 6.0 MPa), the steam consumption for heating for flash evaporation was reduced by 88%. Due to the reduced viscosity of the material in the supercritical state, the throughput of the screw extruder was increased, and the productivity of the unit increased by 80% to 100%.

[0060] As a result, the method for producing an elastomer proposed in the present invention brings about the following advantageous effects.

[0061] The polymerization temperature and pressure used in the present invention are maintained above the supercritical temperature and pressure of the polymerization system. Polymerization is carried out in a supercritical fluid, which not only significantly reduces the viscosity of the system and promotes an increase in the polymer concentration in the solution, thereby improving production efficiency, but also enables simple separation of the solid and liquid phases after polymerization in the supercritical fluid, significantly reducing the energy consumption for solvent separation and regeneration. Furthermore, by introducing a hexane solvent system, a supercritical system is created in the presence of hexane, enabling supercritical polymerization at relatively low temperatures and pressures, thereby reducing production costs for supercritical polymerization and facilitating preparation for industrial production.

[0062] The foregoing description of the disclosed embodiments enables those skilled in the art to make or practice the present invention. Various modifications to the disclosed embodiments will be apparent to those skilled in the art. The general principles described herein may be applied to other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention should not be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for producing an elastomer, comprising the following steps: introduction of an organic solvent, monomer, a cocatalyst and a main catalyst into a reactor under anhydrous and oxygen-free conditions, wherein the materials undergo a polymerization reaction in the reactor in a mode in which the reaction temperature exceeds the supercritical temperature of the system and the reaction pressure exceeds the supercritical pressure of the system to produce an elastomer; wherein the monomer is one or more of linear or branched α-olefins containing 3-20 carbon atoms and ethylene; where the organic solvent is a C6 alkane; wherein the cocatalyst is one or more selected from the group consisting of a methylaluminoxane compound, a modified methylaluminoxane compound, tris(pentafluorophenyl)borane, triphenylcarbenium tetrakis(pentafluorophenyl)borate, N,N-dimethylaniline tetrakis(pentafluorophenyl)borate, triisobutylaluminum and trimethylaluminum; wherein the base catalyst is one or more selected from the group consisting of diphenylmethylene(cyclopentadienyl)(fluorenyl)zirconium dichloride, diphenylmethylene(cyclopentadienyl)(2-dimethylaminofluorenyl)zirconium dichloride, bis[2-(3',5'-di-tert-butylphenyl)indenyl]zirconium dichloride, dicyclopentadienylbis(phenoxy)zirconium, ethylene-bis(indenyl)bis(phenoxy)zirconium, bis(salicylidenephenylimino)titanium dichloride, [N-(3,5-di-tert-butylsalicylidene)-2-diphenylphosphinophenylimino]titanium trichloride, dimethylsilylenebis(indenyl)zirconium dichloride, dimethylsilylene(tetramethylcyclopentadienyl)(tert-butylamido)dimethyltitanium, dimethylsilylene(3-pyrrolilindenyl)(tert-butylamido)dimethyltitanium, pentamethylcyclopentadienyl(2-phenylphenoxy)titanium dichloride and pentamethylcyclopentadienyl(2,6-diisopropylphenoxy)titanium dichloride; where the reaction temperature is from 135 to 220°C; where the reaction pressure is from 2 to 10 MPa.

2. The method of claim 1, wherein the monomer is one or more selected from the group consisting of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-hexadecene, 1-octadecene and 1-eicosene; and The monomer is dehydrated and deoxygenated before use.

3. The method according to claim 1, wherein the polymerization reaction is carried out in a batch polymerization, semi-continuous polymerization or continuous polymerization mode.

4. The method according to claim 1, wherein the polymerization reaction is carried out for a period of 2 to 120 minutes.

5. The method according to claim 1, wherein the elastomer has a weight average molecular weight from 3000 to 1200000 g / mol, a polydispersity index of 1.0-5.0 and a density from 0.84 to 0.93 g / cm 3 .