A cobalt-based catalyst and a method for producing a polybutadiene complex rich in 1,2-structure

Abstract

The application belongs to the field of olefin polymerization, and particularly relates to a cobalt-based catalyst and a preparation method of polybutadiene composite rich in 1,2-structure. The cobalt-based catalyst contains components A, B, C and D which are independently stored, the component A is a cobalt compound, the component B is an organic aluminum compound, the component C is carbon disulfide, and the component D is a silicon-containing compound. In the cobalt-based catalyst, the catalyst activity, the 1,2-addition directional selectivity and the 1,2-structure content in polybutadiene can be greatly improved by introducing the compound containing silicon-oxygen bond and the synergistic effect of the above components, the crystallization performance is improved to realize in-situ synthesis of polybutadiene composite material rich in 1,2-structure and silicon dioxide, and the production efficiency and product performance are improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of olefin polymerization, and particularly relates to a cobalt-based catalyst and application thereof, and a polybutadiene complex rich in 1,2-structure and a preparation method thereof. BACKGROUND

[0002] Under the action of different types of catalysts, butadiene can be polymerized to synthesize cis-1,4, trans-1,4 and 1,2-structure polybutadiene; when butadiene is subjected to 1,2 addition polymerization, isotactic, syndiotactic and atactic three kinds of 1,2-polybutadiene can be generated.

[0003] Ziegler-Natta type cobalt-based catalysts for the synthesis of high cis-1,4 polybutadiene are generally composed of halide or organic acid salt of cobalt and chlorinated alkyl aluminum, such as cobalt chloride (CoCl2) / dichloroisobutyl aluminum (Al(i-Bu)Cl2), CoCl2 / Al(i-Bu)Cl2 / monochlorodiisobutyl aluminum (Al(i-Bu)2Cl), cobalt isooctanoate (Co(oct)2) / Al(i-Bu)Cl2 / Al(i-Bu)2Cl, CoCl2 / monochlorodiethyl aluminum (AlEt2Cl), Co(oct)2 / AlEt2Cl / H2O, Co(oct)2 / AlEt2Cl / H2O / cyclooctadiene, and Co(oct)2 / hemi-ethyl aluminum chloride / tri-n-octyl aluminum / triethyl amine or triethanol amine, etc., see Goodrich-Gulf Chemicals, Inc. Polymerization process for aliphatic conjugated dienes. US3094514, 1963.06.18; Goodrich-Gulf Chemicals, Inc. Process of polymerizing conjugated dienes with a cobalt salt-hydrocarbyl aluminum compound catalyst. US3135725, 1964.06.02; Goodrich-Gulf Chemicals, Inc. Water modification of hydrocarbyl aluminum compounds employed in Ziegler catalysts used to produce stereoregulated polymerizations of monomeric diolefins. CA795860, 1968.10.01; Goodrich Company. Improved solvent system for butadiene-1,3 polymerization. CA1094248, 1976.04.12; Ube Industries, Ltd. Method for producing polybutadiene rubber and rubber composition. CN101084265B, 2011.03.23; The Dow Chemical Company. Catalyst system for high cis polybutadiene. WO02 / 30997A2, 2002.04.18.In addition, cobalt complex / alkyl aluminum oxide systems such as cobalt chloride 2,6-bis[1-(imine phenyl)ethyl]pyridine or bis(benzimidazolyl)amine cobalt complex / methylaluminoxane systems can also be used, see: Ai P F, Chen L, Jie S Y, Li BG. Polymerization of 1,3-butadiene catalyzed by ion-pair cobalt complexes with (benzimidazolyl)pyridine alcohol ligands. J Mol Catal A-Chem, 2013, 380, 1-9; Cariou R, Chirinos J, Gibson V C, Jacobsen G, Tomov A K, Elsegood M R J. 1,3-butadiene polymerization by bis(benzimidazolyl)amine metal complexes: remarkable microstructural control and a protocol for in-reactor blending of trans-1,4-, cis-1,4- and cis-1,4-co-1,2-vinylpolybutadiene. Macromolecules, 2009, 42(5): 1443-1444.

[0004] Polybutadiene rich in 1,2-structure, referred to as 1,2-polybutadiene, can be divided into atactic and stereoregular 1,2-polybutadiene. Most of the initiation systems or catalyst systems are used for 1,2-addition polymerization of butadiene, and usually atactic 1,2-polybutadiene with 1,2-structure content less than 84% is obtained, such as butyllithium / ether or aldehyde initiation system or tris[di(2-ethylhexyl)phosphoric acid]iron / hydrogenated dihexyl aluminum / hydrogenated dioctyl aluminum / diethyl phosphite, molybdenum pentachloride / tri-n-butyl phosphate / triethyl aluminum, etc. Catalyst system, see: Enichem S P A. Anionic copolymerization of conjugated dienes and vinyl arenes in the presence of alkyl ethers of tetrahydropyranyl methanol. EP856532, 1998.05.08; Bridgestone Corporation. Oxolanyl cyclic acetals as anionic polymerization modifiers. US5112929, 1992.05.12; Shandong Heze Yuhuang Chemical Co., Ltd. Preparation method of atactic 1,2-polybutadiene. CN110343203A, 2019.10.18; Zhao Xuan, Liu Jin-hui, and Hu Jing. MoCl5 / TBP / AlEt3 system initiates butadiene polymerization to prepare high-vinyl polybutadiene containing crystals. Polymer Material Science and Engineering, 2019, 35:7-12. To prepare crystallizable syndiotactic 1,2-polybutadiene, special catalyst systems are usually required, such as cobalt compound / organic aluminum / triphenyl phosphine or tri-mesityl phosphine, iron rich in 1,2-structure and 2-ethylhexanoate / triisobutyl aluminum / dialkyl phosphite, etc. See Japan Synthetic Rubber Co., Ltd. Process for the catalytic preparation of 1,2-polybutadiene having a high percentage of vinyl configuration. US3498963, 1970.03.03; Japan Synthetic Rubber Co., Ltd. Process for the preparation of 1,2-polybutadiene. US4182813, 1980.01.08; Bridgestone Corporation. Syndiotactic 1,2-polybutadiene with crystalline melting temperature between 130-180℃ is prepared by using [HP(O)(OR)2] or phosphorus acid ring catalyst system, see: Bridgestone Corporation.Iron-based catalyst composition and process for producing syndiotactic 1,2-polybutadiene. EP0994129A1, 2000.04.19; Bridgestone Corporation. Process for producing syndiotactic 1,2-polybutadiene and iron-based catalyst composition for use therein. EP0994130A, 2000.04.19; Bridgestone Corporation. Preparation of conjugated diene polymers by using an iron-based catalyst system. WO0149753A1, 2001.07.12; UBE Industries Limited. Method of producing 1,2-polybutadiene. US4153767, 1979.05.08; Ashitaka H, Ishikawa H, Ueno H, Nagasaka A. Syndiotactic 1,2-polybutadiene with Co-CS2 catalyst system. I. Preparation, properties, and application of highly crystalline syndiotactic 1,2-polybutadiene. J. Polym. Sci. Polym Chem. Ed., 1983, 21, 1853-1860. SUMMARY

[0005] The present application aims to provide a cobalt-based catalyst and its application, and a 1,2-structure-rich polybutadiene compound and its preparation method.

[0006] Specifically, the present application provides a cobalt-based catalyst, wherein the cobalt-based catalyst contains components A, B, C and D which are independently stored, the component A is a cobalt compound, the component B is an organic aluminum compound, the component C is carbon disulfide, and the component D is a silicon-containing compound.

[0007] The present application also provides an application of the cobalt-based catalyst in an olefin polymerization reaction.

[0008] The present application also provides a method for preparing 1,2-polybutadiene, wherein the method comprises mixing the components of the above-mentioned cobalt-based catalyst in a certain order with a butadiene monomer / hydrocarbon solvent solution in any one of the following mixing modes: D-A-E-B-C, D-E-A-B-C, D-E-B-A-C, E-D-A-B-C, E-D-B-A-C, D-E-A-C-B or E-D-A-C-B, and then performing a reaction under olefin polymerization conditions to obtain a 1,2-structure-rich polybutadiene complex, wherein E represents a butadiene monomer / hydrocarbon solvent solution.

[0009] In addition, the present application also provides a 1,2-structure-rich polybutadiene complex prepared by the above-mentioned method.

[0010] The technical scheme provided by the present application has the following beneficial effects:

[0011] In the cobalt-based catalyst, by introducing a compound containing a silicon-oxygen bond and the synergistic effect of the above-mentioned several components, the polymerization reactivity can be greatly improved, and the content of 1,2-structure in the polymerization product polybutadiene can be adjusted. In this cobalt-based catalytic reaction system, the monomer conversion rate increases with the increase of the amount of the silicon-containing compound, and by adjusting the D component, a 1,2-structure-rich polybutadiene complex with different D component contents can be obtained. DETAILED DESCRIPTION

[0012] The present application will be described in detail below.

[0013] The cobalt-based catalyst provided by the present application contains components A, B, C and D which are independently stored, the component A is a cobalt compound, the component B is an organic aluminum compound, the component C is carbon disulfide, and the component D is a silicon-containing compound.

[0014] The cobalt compound is preferably an organic acid salt of cobalt and / or cobalt acetylacetonate, and specific examples thereof include, but are not limited to, at least one of cobalt naphthenate, cobalt benzoate, cobalt stearate, cobalt octanoate, cobalt iso-octanoate, cobalt neodecanoate, cobalt oleate, cobalt linoleate, cobalt diacetylacetonate and cobalt triacetylacetonate, and particularly preferably at least one selected from cobalt naphthenate, cobalt octanoate, cobalt iso-octanoate and cobalt neodecanoate.

[0015] The organic aluminum compound is preferably a compound of general formula AlR 1 3 and / or general formula AlHR 2 2, wherein R 1 and R 2each independently is a C1-C6 alkyl group, preferably each independently is an ethyl group, a propyl group or a butyl group. Specifically, examples of the organoaluminum compound include, but are not limited to, at least one selected from the group consisting of trimethylaluminum, triethylaluminum, tripropylaluminum, tributylaluminum, triisobutylaluminum, tripentylaluminum, trihexylaluminum, diethylaluminum hydride, dibutylaluminum hydride and diisobutylaluminum hydride, preferably at least one selected from the group consisting of triethylaluminum, triisobutylaluminum, diethylaluminum hydride, dibutylaluminum hydride and diisobutylaluminum hydride.

[0016] The silicon-containing compound is preferably a silicone oil and / or a silicon dioxide. Specifically, examples of the silicone oil include, but are not limited to, at least one selected from the group consisting of methyl silicone oil, ethyl silicone oil, phenyl silicone oil, methyl hydrogen-containing silicone oil, methyl phenyl silicone oil, methyl chlorophenyl silicone oil, methyl ethoxy silicone oil, methyl trifluoropropyl silicone oil, methyl vinyl silicone oil, methyl hydroxyl silicone oil, ethyl hydrogen-containing silicone oil, hydroxyl hydrogen-containing silicone oil and cyano-containing silicone oil, preferably at least one selected from the group consisting of methyl silicone oil, ethyl silicone oil, methyl hydrogen-containing silicone oil, ethyl hydrogen-containing silicone oil and hydroxyl hydrogen-containing silicone oil.

[0017] The silicon dioxide is a precipitated or fumed silicon dioxide. The specific surface area of the silicon dioxide is preferably 150 to 450 m 2 / g, more preferably 175 to 350 m 2 / g; the surface hydroxyl group content is preferably 1 x 10 17 to 7 x 10 17 / m 2 , more preferably 2 x 10 17 to 5 x 10 17 / m 2 .

[0018] The present application also provides use of the cobalt-based catalyst in an olefin polymerization reaction.

[0019] Specific examples of the olefin include, but are not limited to, at least one selected from the group consisting of butadiene, isoprene, 2-methyl-1,3-pentadiene, 2,4-hexadiene, styrene and methylstyrene, preferably at least one selected from the group consisting of butadiene, isoprene, styrene and methylstyrene, more preferably at least one selected from the group consisting of butadiene, isoprene and styrene.

[0020] The preparation method of 1,2-polybutadiene provided by the present application comprises mixing the components of the above-mentioned cobalt-based catalyst in a certain order with a butadiene monomer / hydrocarbon solvent solution, the mixing mode being selected from any one of D-E-A-B-C, D-E-B-A-C, E-D-A-B-C, E-D-B-A-C, D-E-A-C-B or E-D-A-C-B, and then performing reaction under olefin polymerization reaction conditions to obtain a polybutadiene compound rich in 1,2-structure, wherein E represents a butadiene monomer / hydrocarbon solvent solution. The feeding order of the materials has certain influence on catalytic activity and catalytic effect, and feeding according to the mode provided by the present application enables the cobalt-based catalyst to fully exert catalytic activity and better adjust the microstructure and content of 1,2-polybutadiene.

[0021] The present application does not have special limitations on the addition amount of each material, and preferably, the molar ratio of the cobalt compound to the monomer is (1x10 -6 ~1x10 -3 ):1, more preferably (1x10 -5 ~5x10 -4 ):1, and most preferably (1.0x10 -4 ~2.5x10 -4 ):1; the molar ratio of the organic aluminum compound to the monomer is (1x10 -4 ~5x10 -2 ):1, more preferably (5x10 -4 ~1x10 -2 ):1, and most preferably (1x10 -3 ~5x10 -3 ):1; the mass ratio of the silicon-containing compound to the monomer is (0.1x10 -2 ~10x10 -2 ):1, more preferably (0.2x10 -2 ~8x10 -2 ):1, and most preferably (0.4x10 -2 ~6.0x10 -2 ):1; and the molar ratio of carbon disulfide to the monomer is (2.0x10 -4 ~4.5x10 -3 ):1, more preferably (2.5x10 -4 ~4.0x10 -3 ):1, and most preferably (2.8x10 -4 ~3.8x10 -3 ):1.

[0022] The olefin polymerization reaction of the present application is not particularly limited in terms of conditions, and generally includes a reaction temperature of -30 to 110°C, preferably -10 to 100°C, and more preferably 30 to 60°C, and a reaction time of 30 minutes to 30 hours, preferably 1 hour to 20 hours, and more preferably 1 hour to 4 hours. When the polymerization reaction temperature is low, the polymerization time can be extended, and when the polymerization reaction temperature is high, the polymerization time can be shortened.

[0023] During the olefin polymerization reaction, all operations are performed under inert gas protection, preferably under nitrogen protection. At the end of the polymerization reaction, a compound such as water, an alcohol, or a phenol can be used as a terminating agent to terminate the reaction. In addition, a carboxylic acid, an amine compound, an ester compound, or the like can be added to the terminating agent as an auxiliary agent.

[0024] The olefin polymerization reaction can be performed in a single polymerization reactor device, a plurality of polymerization reactor devices connected in series, or a pipe reactor, and can be performed using a continuous polymerization operation method or a batch polymerization operation method. The olefin polymerization reaction can be bulk polymerization or solution polymerization.

[0025] When solution polymerization is used, a hydrocarbon compound is generally used as a solvent. The timing of adding the solvent is not particularly limited, and the solvent can be added before, after, or during the addition of the components of the cobalt-based catalyst and the butadiene monomer, or the solvent can be mixed with any one of the components of the cobalt-based catalyst and the butadiene monomer and then added to the reaction system. The hydrocarbon compound can be at least one of an aliphatic hydrocarbon, an alicyclic hydrocarbon, and an aromatic hydrocarbon, and specific examples thereof include, but are not limited to, at least one of butane, pentane, hexane, cyclohexane, heptane, octane, methylcyclohexane, benzene, toluene, xylene, and mesitylene, preferably at least one selected from the group consisting of butane, pentane, hexane, cyclohexane, and toluene. In addition, the concentration of the monomer in the solvent can be 40 to 200 g / L, preferably 80 to 180 g / L, and more preferably 100 to 150 g / L.

[0026] Compared with the prior art, the present application achieves a remarkable effect, the catalyst activity is improved, the 1,2-addition directional selectivity is improved, the 1,2-structure content in the polybutadiene is increased, the crystallization melting enthalpy is increased, and a composite material of polybutadiene rich in 1,2-structure and silicon dioxide can be synthesized in situ, which helps to improve production efficiency and product performance and reduce catalyst cost.

[0027] The present application is illustrated by the following examples, which do not constitute a limitation on the scope or implementation method of the present application.

[0028] In the following examples and comparative examples:

[0029] (1) The infrared spectrum of the soluble fraction was determined using a Nicolet Fourier transform infrared spectrometer (FTIR) model 6700. The scanning range was set to 400-2000 cm -1 , and the microstructure content of the polymer was calculated.

[0030] (2) The melting point, melting enthalpy and glass transition temperature of the polymerization product were determined using a TA differential scanning calorimeter (DSC) model Q200. The test conditions included a temperature range of -130-250°C and a heating rate of 10°C / min.

[0031] Example 1

[0032] After 26 mg of silica (SiO2, specific surface area 293 m 2 / g, surface hydroxyl content 2.59 x 10 17 / m 2 ) was added to a dry polymerization reactor under nitrogen protection, a cobalt neodecanoate / hexane solution, a butadiene / hexane solution ([Bd] = 2.4 mol / L), a triisobutyl aluminum / hexane solution and a carbon disulfide / hexane solution were sequentially added to carry out butadiene polymerization, wherein the molar ratio of cobalt to monomer was 2.0 x 10 -4 : 1, the molar ratio of aluminum to monomer was 4.5 x 10 -3 : 1, the molar ratio of carbon disulfide to monomer was 2.5 x 10 -3 : 1, and the SiO2 was 0.5% of the mass of the monomer. After the polymerization reaction was carried out at 30°C for 3 h, a hexane solution containing 1 wt% of 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propyl octadecyl ester was added to the polymerization reactor to terminate the reaction, and the polymerization product was washed and dried to constant weight in a vacuum oven at 40°C. The yield of the polymerization product was 64.9%. The 1,2-structure content of the obtained polybutadiene was 83.1%, the cis-1,4 structure content was 0.9%, and the trans-1,4 structure content was 15.9%. The mass content of silica in the polybutadiene composite was 0.8%. The crystalline melting temperature range of the polymer was 148-202°C, the melting peak temperature was 193°C, and the melting enthalpy was 40.4 J / g.

[0033] Compared with Comparative Example 1, under the same test conditions, the catalytic activity of the cobalt-based catalyst described in Example 1 was increased by 13.1% after the addition of SiO2, the 1,2-structure content of the polybutadiene was increased by 4.0%, and the crystalline melting enthalpy of the polymer was increased by 12.5%.

[0034] Example 2

[0035] The polymerization method and the rest of the conditions are the same as in Example 1, except that the amount of silica added is 259 mg, so that SiO2 is 5.0% of the mass of the monomer. The yield of the polymerization reaction product is 78.5%, the 1,2-structure content in the obtained polybutadiene is 82.4%, the cis-1,4 structure content is 3.5%, and the trans-1,4 structure content is 14.1%; the silica content in the polybutadiene composite is 6.0%; the crystalline melting temperature range of the polymer composite is 156-200°C, the melting peak temperature is 193°C, and the melting enthalpy is 44.0 J / g.

[0036] Compared with Comparative Example 1, under the same test conditions, the catalytic activity of the cobalt-based catalyst described in Example 2 is increased by 36.5% after the addition of SiO2, and the 1,2-structure content in the polybutadiene is increased by 3.1%, and the crystalline melting enthalpy of the polymer is increased by 22.6%.

[0037] Example 3

[0038] The polymerization method and the rest of the conditions are the same as in Example 1, except that the silicon-containing compound is replaced with highly dispersed white carbon black 383, and the amount added is 104 mg, so that the highly dispersed white carbon black is 2.0% of the mass of the monomer. The yield of the polymerization reaction product is 91.6%, the 1,2-structure content in the polybutadiene is 84.7%, the cis-1,4 structure content is 11.8%, and the trans-1,4 structure content is 3.5%; the silica mass content in the polybutadiene composite is 2.6%; the crystalline melting temperature range of the polymer composite is 164-202°C, and the melting peak temperature is 193°C.

[0039] Compared with Comparative Example 1, under the same test conditions, the catalytic activity of the cobalt-based catalyst described in Example 3 is increased by 59.6% after the addition of SiO2, and the 1,2-structure content in the polybutadiene is increased by 6.0%.

[0040] Example 4

[0041] The polymerization method and the rest of the conditions are the same as in Example 1, except that SiO2 (specific surface area 308 m 2 / g, surface hydroxyl content 2.87 x 10 17 / m 2 ) is 1.5% of the mass of the monomer, and the molar ratio of carbon disulfide to monomer is 3.0 x 10 -4 :1. The yield of the polymerization reaction product is 69.1%, the 1,2-structure content in the polybutadiene is 84.7%, the cis-1,4 structure content is 1.2%, and the trans-1,4 structure content is 14.0%; the silica mass content in the polybutadiene composite is 2.2%; the crystalline melting temperature range is 154-201°C, the melting peak temperature is 194°C, and the melting enthalpy is 43.1 J / g.

[0042] Compared with Comparative Example 1, the addition of SiO2 to the cobalt-based catalyst described in Example 4 increased the catalytic activity by 20.4%, the 1,2-structure content in polybutadiene by 4.8%, and the enthalpy of crystallization by 20.1%.

[0043] Example 5

[0044] The polymerization method and other conditions were the same as in Example 1, except that the amount of silica added was 1.5% of the monomer mass, and the molar ratio of carbon disulfide to monomer was 3.5 × 10⁻⁶. -3 1. The yield of the polymerization product was 65.8%. The content of 1,2-structure in polybutadiene was 78.6%, the content of cis-1,4-structure was 4.2%, and the content of trans-1,4-structure was 17.1%. The mass content of silica in the polybutadiene composite was 2.3%. The polymer crystallization melting temperature range was 161–201℃, the melting peak temperature was 192℃, and the melting enthalpy was 42.3 J / g.

[0045] Compared with Comparative Example 1, the addition of SiO2 to the cobalt-based catalyst in Example 5 increased the catalytic activity by 14.6% and the crystallization melting enthalpy by 17.8%.

[0046] Example 6

[0047] The polymerization method and other conditions are the same as in Example 1, except that 52 mg of silica (with a specific surface area of ​​308 m²) is added. 2 / g, with a surface hydroxyl content of 2.87×10 17 pcs / m 2 The polymerization reaction yielded a product yield of 69.9%, with polybutadiene containing 84.4% 1,2-structure, 6.9% cis-1,4-structure, and 8.8% trans-1,4-structure. The polybutadiene composite contained 1.4% silica by mass. The polymer crystallization melting temperature range was 145–195 °C, the melting peak temperature was 186 °C, and the enthalpy of melting was 35.9 J / g.

[0048] Compared with Comparative Example 1, under the same experimental conditions, the addition of SiO2 to the cobalt-based catalyst described in Example 6 increased the catalytic activity by 21.8% and the 1,2-structure content in polybutadiene by 5.6%.

[0049] Example 7

[0050] The polymerization method and other conditions were the same as in Example 6, except that the molar ratio of carbon disulfide to monomer was 1.0 × 10⁻⁶. -3:1. The yield of the polymerization product was 57.1%, the content of 1,2-structure in the polybutadiene was 85.7%, the content of cis-1,4-structure was 0.3%, the content of trans-1,4-structure was 14.0%, the content of SiO2 in the polybutadiene composite was 1.4%, the crystalline melting temperature range of the polymer was 156-198°C, the melting peak temperature was 192°C, and the melting enthalpy was 40.5 J / g.

[0051] Compared with Comparative Example 1, under the same test conditions, the content of 1,2-structure in the polybutadiene increased by 7.3% and the crystalline melting enthalpy increased by 12.8% after adding SiO2 to the cobalt-based catalyst described in Example 7.

[0052] Example 8

[0053] The polymerization method and the rest of the conditions were the same as in Example 7, except that the hexane solution of SiO2, the hexane solution of cobalt neodecanoate, the hexane solution of butadiene monomer and triisobutyl aluminum were mixed for 40 min, and then the hexane solution of carbon disulfide was added. The yield of the polymerization product was 59.7%, the content of 1,2-structure in the polybutadiene was 84.5%, the content of cis-1,4-structure was 0.3%, the content of trans-1,4-structure was 15.2%, the content of SiO2 in the polybutadiene composite was 1.4%, the crystalline melting temperature range of the polymer was 142-201°C, the melting peak temperature was 194°C, and the melting enthalpy was 52.8 J / g.

[0054] Compared with Comparative Example 1, under the same test conditions, the catalytic activity increased by 4.0%, the content of 1,2-structure in the polybutadiene increased by 5.8%, and the melting enthalpy increased by 47.1% after adding SiO2 to the cobalt-based catalyst described in Example 8.

[0055] Example 9

[0056] The polymerization method and the rest of the conditions were the same as in Example 7, except that the silicon-containing compound was dimethyl silicone oil, and the amount of addition was 0.5% of the mass of the monomer. The yield of the polymerization product was 59.2%, the content of 1,2-structure in the polybutadiene was 80.2%, the content of cis-1,4-structure was 0.6%, the content of trans-1,4-structure was 19.2%, the content of dimethyl silicone oil in the polybutadiene composite was 0.8%. The crystalline melting temperature range of the polymer was 147-200°C, the melting peak temperature was 194°C, and the crystalline melting enthalpy was 43.9 J / g.

[0057] Compared with Comparative Example 1, under the same test conditions, the catalytic activity increased by 3.1% and the crystalline melting enthalpy increased by 22.3% after adding dimethyl silicone oil to the cobalt-based catalyst described in Example 9.

[0058] Example 10

[0059] The polymerization method and the rest of the conditions are the same as in Example 6, except that the order of feeding the materials is different, i.e. silica, butadiene / hexane solution, cobalt neodecanoate / hexane solution, triisobutyl aluminum / hexane solution and carbon disulfide / hexane solution. The yield of the polymerization product is 66.7%, the 1,2-structure content of the polybutadiene is 86.8%, the cis-1,4 structure content is 1.4%, and the trans-1,4 structure content is 11.8%; the silica content in the polybutadiene composite is 1.4%; the crystalline melting temperature range of the polymer is 149-201°C, the melting peak temperature is 194°C, and the melting enthalpy is 43.8 J / g.

[0060] Compared with Comparative Example 1, under the same test conditions, the catalytic activity of the cobalt-based catalyst described in Example 10 is increased by 16.2% after the addition of SiO2, the 1,2-structure content of the polybutadiene is increased by 8.6%, and the crystalline melting enthalpy is increased by 22.0%.

[0061] Comparative Example 1

[0062] Under the protection of nitrogen, 40 mL of a butadiene / hexane solution ([Bd]=2.4 mol / L) was added to a dry polymerization reactor, followed by the sequential addition of a cobalt neodecanoate / hexane solution, a triisobutyl aluminum / hexane solution and a carbon disulfide / hexane solution, which were mixed uniformly, and the molar ratio of cobalt to monomer was 2.0x10 -4 :1, the molar ratio of aluminum to monomer was 4.5x10 -3 :1, and the molar ratio of carbon disulfide to monomer was 2.5x10 -3 :1. After the polymerization reaction at 30°C for 3 h, a hexane solution containing 1 wt% of 2,6-di-tert-butyl-p-cresol was added to the polymerization reactor to terminate the reaction, which was washed clean and then dried to a constant weight in a vacuum oven at 40°C. The yield of the polymerization product was 57.4%. The 1,2-structure content of the obtained polybutadiene was 79.9%, the cis-1,4 structure content was 1.9%, and the trans-1,4 structure content was 18.1%; the crystalline melting temperature range of the polymer was 162-199°C, the melting peak temperature was 193°C, and the melting enthalpy was 35.9 J / g.

[0063] The above describes the preferred embodiments of the present application in detail, but the present application is not limited to the specific details in the above-described embodiments, and various simple modifications can be made to the technical solutions of the present application within the technical concept of the present application, and these simple modifications all belong to the protection scope of the present application.

[0064] In addition, it should be noted that each specific technical feature described in the above-described specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present application will not describe various possible combinations again.

[0065] Furthermore, the various embodiments can also be combined, if not in contradiction, as long as they do not deviate from the spirit of the present application, which should be considered as disclosed.

Claims

1. A cobalt-based catalyst characterized in that, The cobalt-based catalyst contains components A, B, C and D, which are independently stored, the component A is a cobalt compound, the component B is an organic aluminum compound, the component C is carbon disulfide, and the component D is a silicon-containing compound; The silicon-containing compound is a silicone oil and / or a silicon dioxide; The silicone oil is at least one selected from methyl silicone oil, ethyl silicone oil, phenyl silicone oil, methyl hydrogen-containing silicone oil, methyl phenyl silicone oil, methyl chlorophenyl silicone oil, methyl ethoxy silicone oil, methyl trifluoropropyl silicone oil, methyl vinyl silicone oil, methyl hydroxyl silicone oil, ethyl hydrogen-containing silicone oil, hydroxyl hydrogen-containing silicone oil and cyano-containing silicone oil; The specific surface area of the silica is 150 to 450 m 2 / g, and the surface hydroxyl group content is 1 x 10 17 to 7 x 10 17 / m 2 .

2. The cobalt-based catalyst according to claim 1, characterized in that, The cobalt compound is an organic acid salt of cobalt and / or cobalt acetylacetone.

3. The cobalt-based catalyst according to claim 2, characterized in that The cobalt compound is at least one selected from cobalt naphthenate, cobalt benzoate, cobalt stearate, cobalt octanoate, cobalt iso-octanoate, cobalt neodecanoate, cobalt oleate, cobalt linoleate, cobalt diacetylacetone and cobalt triacetylacetone.

4. The cobalt-based catalyst according to claim 3, characterized in that, The cobalt compound is at least one selected from cobalt naphthenate, cobalt octanoate, cobalt iso-octanoate and cobalt neodecanoate.

5. The cobalt-based catalyst according to claim 1, wherein The organoaluminum compound is a compound of the general formula AlR 1 3 and / or a compound of the general formula AlHR 2 2, R 1 and R 2 are each independently a Ci-C6alkyl.

6. The cobalt-based catalyst according to claim 5, characterized in that, The organic aluminum compound is at least one selected from trimethyl aluminum, triethyl aluminum, tripropyl aluminum, tributyl aluminum, triisobutyl aluminum, tripentyl aluminum, trihexyl aluminum, diethyl aluminum hydride, dibutyl aluminum hydride and diisobutyl aluminum hydride.

7. The cobalt-based catalyst according to claim 6, characterized in that The organic aluminum compound is at least one selected from triethyl aluminum, triisobutyl aluminum, diethyl aluminum hydride, dibutyl aluminum hydride and diisobutyl aluminum hydride.

8. The cobalt-based catalyst according to claim 1, wherein The silicone oil is at least one selected from methyl silicone oil, ethyl silicone oil, methyl hydrogen-containing silicone oil, ethyl hydrogen-containing silicone oil and hydroxyl hydrogen-containing silicone oil; The specific surface area of the silica is 175 to 350 m 2 / g, and the surface hydroxyl group content is 2 x 10 17 ~ 5 x 10 17 / g. 2 .

9. Use of the cobalt-based catalyst according to any one of claims 1-8 in an olefin polymerization reaction.

10. A process for the preparation of a polybutadiene compound enriched in 1,2- structure, characterized in that, The method comprises mixing the components of the cobalt-based catalyst according to any one of claims 1-8 in a certain order with a butadiene monomer / hydrocarbon solvent solution, the mixing mode is selected from any one of D-E-A-B-C, D-E-B-A-C, E-D-A-B-C, E-D-B-A-C, D-E-A-C-B or E-D-A-C-B, and then reacting under olefin polymerization reaction conditions to obtain a 1,2-structure-rich polybutadiene composite, wherein E represents a butadiene monomer / hydrocarbon solvent solution.

11. The method for producing a polybutadiene compound rich in 1,2- structure according to claim 10, characterized by, The molar ratio of the cobalt compound to the monomer is (1 x 10 -6 ~1 x 10 -3 ): 1; the molar ratio of the organoaluminum compound to the monomer is (1 x 10 -4 ~5 x 10 -2 ): 1; the molar ratio of the carbon disulfide to the monomer is (2.0 x 10 -4 ~4.5 x 10 -3 ): 1; and the mass ratio of the silicon-containing compound to the monomer is (0.1 x 10 -2 ~10 x 10 -2 ):

1.

12. The method for producing a polybutadiene compound rich in 1,2-structure according to claim 11, characterized by, The molar ratio of the cobalt compound to the monomer is (1 x 10 -5 ~5 x 10 -4 ): 1; the molar ratio of the organoaluminum compound to the monomer is (5 x 10 -4 ~1 x 10 -2 ): 1; the molar ratio of the carbon disulfide to the monomer is (2.5 x 10 -4 ~4.0 x 10 -3 ): 1; and the mass ratio of the silicon-containing compound to the monomer is (0.2 x 10 -2 ~8 x 10 -2 ):

1.

13. The method for producing a polybutadiene compound rich in 1,2- structure according to claim 12, characterized by, The molar ratio of the cobalt compound to the monomer is (1 x 10 -4 ~2 x 10 -4 ): 1; the molar ratio of the organoaluminum compound to the monomer is (1 x 10 -3 ~5 x 10 -3 ): 1; the molar ratio of the carbon disulfide to the monomer is (2.8 x 10 -4 ~3.8 x 10 -3 ): 1; and the mass ratio of the silicon-containing compound to the monomer is (0.4 x 10 -2 ~6 x 10 -2 ):

1.

14. The process for preparing a polybutadiene compound rich in 1,2- structure according to any one of claims 10 to 13, characterized in that, The conditions of the olefin polymerization reaction include a reaction temperature of -30 ~ 110℃; and a reaction time of 0.5 ~ 30 h.

15. The method for producing a polybutadiene compound rich in 1,2- structure according to claim 14, characterized by, The conditions of the olefin polymerization reaction include a reaction temperature of -20 ~ 105℃; and a reaction time of 1 ~ 20 h.

16. The method for producing a polybutadiene compound rich in 1,2- structure according to claim 15, characterized by, The conditions of the olefin polymerization reaction include a reaction temperature of -10 ~ 100℃; and a reaction time of 1 ~ 4 h.

17. A 1,2-structure-rich polybutadiene composite prepared by the method according to any one of claims 10-16.