Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F210/00—Copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F210/00—Copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
  • C08F210/02—Ethene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F210/00—Copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
  • C08F210/16—Copolymers of ethene with alpha-alkenes, e.g. EP rubbers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F4/00—Polymerisation catalysts
  • C08F4/42—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors
  • C08F4/44—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides
  • C08F4/60—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides together with refractory metals, iron group metals, platinum group metals, manganese, rhenium technetium or compounds thereof
  • C08F4/62—Refractory metals or compounds thereof
  • C08F4/64—Titanium, zirconium, hafnium or compounds thereof
  • C08F4/659—Component covered by group C08F4/64 containing a transition metal-carbon bond
  • C08F4/65912—Component covered by group C08F4/64 containing a transition metal-carbon bond in combination with an organoaluminium compound
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F4/00—Polymerisation catalysts
  • C08F4/42—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors
  • C08F4/44—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides
  • C08F4/60—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides together with refractory metals, iron group metals, platinum group metals, manganese, rhenium technetium or compounds thereof
  • C08F4/62—Refractory metals or compounds thereof
  • C08F4/64—Titanium, zirconium, hafnium or compounds thereof
  • C08F4/659—Component covered by group C08F4/64 containing a transition metal-carbon bond
  • C08F4/65916—Component covered by group C08F4/64 containing a transition metal-carbon bond supported on a carrier, e.g. silica, MgCl2, polymer
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F4/00—Polymerisation catalysts
  • C08F4/42—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors
  • C08F4/44—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides
  • C08F4/60—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides together with refractory metals, iron group metals, platinum group metals, manganese, rhenium technetium or compounds thereof
  • C08F4/62—Refractory metals or compounds thereof
  • C08F4/64—Titanium, zirconium, hafnium or compounds thereof
  • C08F4/659—Component covered by group C08F4/64 containing a transition metal-carbon bond
  • C08F4/6592—Component covered by group C08F4/64 containing a transition metal-carbon bond containing at least one cyclopentadienyl ring, condensed or not, e.g. an indenyl or a fluorenyl ring
  • C08F4/65922—Component covered by group C08F4/64 containing a transition metal-carbon bond containing at least one cyclopentadienyl ring, condensed or not, e.g. an indenyl or a fluorenyl ring containing at least two cyclopentadienyl rings, fused or not
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S526/00—Synthetic resins or natural rubbers -- part of the class 520 series
  • Y10S526/943—Polymerization with metallocene catalysts

Definitions

• the present invention relates to a method for producing an ethylene copolymer, and more particularly to a method suitable for producing an ethylene copolymer by a slurry polymerization method.
• Solution polymerization, slurry polymerization, and gas phase polymerization are known as methods for industrially producing polyolefins from olefins.
• a solution polymerization method since a polymer is dissolved in a liquid phase and polymerized in a homogeneous phase, a large amount of energy is required to separate the polymer and the solvent, and there is a disadvantage that the apparatus becomes complicated.
• the polymer in the slurry polymerization method and the gas phase polymerization method, the polymer is polymerized in a liquid phase and a gas phase to form a solid particulate polymer, so that the polymer can be easily separated and the equipment can be simplified.
• It has the advantage of:
• it is necessary that the solid particles do not adhere to each other, but in the production of an adhesive rubber-like polymer, it is necessary to use a method in a reactor or a transportation route. As a result, a phenomenon occurs in which particles adhere to each other or between the particles and the vessel wall, and these deposits accumulate, making it impossible to produce a polymer (felling).
• slurry-like polymerization methods and gas-phase polymerization methods form polymer particles having low crystallinity and low adhesiveness even in polyolefins. Although it is used in the production of all polymers, it requires rubber-like physical properties. Ethylen-1 ⁇ -olefin copolymer, ethylene-1 ⁇ -olefin which is polymerized using at least one transition metal catalyst of Zr and Hf -In industrial production of ethylene copolymers such as non-conjugated gen copolymers, long-term continuous operation can cause extremely severe fouling. And could not.
• a solution polymerization method or a slurry monopolymerization method substantially similar to a solution polymerization method by adding a large amount of a solvent is employed.
• Japanese Patent Application Laid-Open No. 60-94412 discloses that when slurry polymerization is carried out in the presence of a Ti-based catalyst, a polysiloxane compound is previously formed on the inner wall of the reactor or on the surface of the portion where the reaction catalyst comes into contact. It has been proposed to prevent a rubber-like polymer formed by forming a film layer from adhering to a wall surface or the like.
• V, Zr and Hf should be at least as low as in slurry polymerization using Ti-based catalysts.
• the generated polymer is a more random and rubbery copolymer, the occurrence of burning is severe.
• the above method requires a step of forming a polysiloxane coating layer on the inner wall of the reactor or the surface where the reaction medium comes into contact, which increases the production cost. There was a drawback.
• An object of the present invention is to solve the above-mentioned problems of the prior art
• An object of the present invention is to provide a method for producing an ethylene copolymer capable of effectively preventing the occurrence of the above-mentioned fouling and enabling continuous operation.
• the present inventors have conducted intensive studies and as a result, found that at least one transition metal-based supported catalyst of V, Zr, and Hf compounds was present and that the silicide was present in a platform system.
• the present inventors have found that the coexistence of the coonet drastically reduces the filing and enables the continuous operation, and has reached the present invention.
• the present invention relates to a method in which ethylene and ⁇ -olefin or a non-conjugated gen and ethylene are mixed in a polymerization medium which does not substantially dissolve the copolymer to be produced, with V, In the presence of a catalyst supporting at least one transition metal compound of Zr and Hf compounds and an organic aluminum compound, the polysiloxane compound is
• An object of the present invention is to provide a method for producing an ethylene copolymer, which is characterized by co-existing and copolymerizing.
• Examples of the monoolefin used in the present invention include propylene, 1-butene, 1-hexene, 4-methylenpentene-1 and the like. .
• non-conjugated gen used in the present invention examples include i, 4-hexagene, dicyclopentene, methylencyclopentagen, and vinylno.
• the ethylene copolymers of the present invention such as rubornane, 5-ethylidene-2-nonolepollene, and isopropenylnorbornane, are examples of the resulting copolymer. It is produced by a slurry polymerization method in a polymerization medium of a hydrocarbon having 3 to 5 carbon atoms, which is substantially insoluble, in the presence of a supported catalyst and in the presence of a polysiloxane compound.
• hydrocarbons having 3 to 5 carbon atoms examples include propylene, propane, n-butane, isobutane, 1-ptene, 2-ptene, and isobutylene.
• N pentane, isopentan, pen mouth pentane, pentenes, etc. These may be used alone or as a mixture, and may be accompanied by a solvent such as n-hexane or toluene as long as they contain these as main components.
• the above-mentioned supported catalyst is used as a solid catalyst by supporting at least one transition metal compound and an organic aluminum compound of V, Zr and Hf compounds on a particulate carrier.
• the supported catalyst is used to form prepolymers involving solid catalyst particles.
• the pre-polymerization may be performed under the conditions to be provided, and the pre-polymer wrapped with the polymer may be used.
• the transition metal compound may include at least one compound of V, Zr, and Hf compounds, for example,
• each R 1 is independently C i-C 2.
• R 2 is - A linear, branched or cyclic alkylene group of C 6 , an alkyl-substituted silanylene group or an alkyl-substituted silaalkylene group of Si i to Si 2
• each X is a separate Alkyl, aryl, halide, hydride or zirconocene dimer, oxygen bridge, y is 2, 3 or 4, b is 0 or 1)
• Zr compound for example, dimethylsiliconbis (tetranodroindenyl) zirconium chloride, tetrahydroidenyldenyl quinolone ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ ⁇ ⁇
• R 1 , R 2 and R 3 are the same or different and are an alkyl group or alkoxy group having 1 to 14 carbon atoms, a halogen atom or a hydrogen atom, provided that at least One, more preferably two are alkyl groups), the general formula R 4 R 5 A &-0-A £ R 6 R 7
• R 4 , R 5 , R 6 and R 7 are the same or different and are an alkyl group or an alkoxy group having 1 to 14 carbon atoms), and the like.
• these include, for example, triethyl aluminum, tripropyl aluminum, triisobutylaluminum, and trihexyl aluminum.
• Perimeter aluminum, trioctylaluminum, dimethylaluminum chloride, and genoareaminium chloride Ethyl alcohol, hydride, ethyl alminum ethoxide, ethyl alminum sesquichloride, Ethyl olenominium sesquichloride, echso olenominium dimethyl chloride, vis (Jechinorea luminum) oxide And the like.
• R 8 is an alkyl group having 1 to 5 carbon atoms such as methyl, ethyl, propyl, butyl, pentyl, etc., and n is an integer of 1 to 40
• organic aluminum compounds can be used alone or in combination. Further, an activity improver, a modifier and the like suitable for each transition metal may be added.
• the particle size is 1 as a particulate carrier! ) To ⁇ 0 / im of a granular or particulate inorganic or organic compound.
• porous oxide is rather preferred, in particular S i 0 2, A & 2 0 3, M g O, Z r 0 2,
• Examples of the organic carrier include granular or fine solid particles of an organic compound having a particle size of 10 to 300 / im.
• Examples of the organic compound include ethylene, propylene, and 1-butene.
• the polysiloxane compound used in the present invention coexists with the polymerization reaction system and prevents adhesion of the ethylene copolymer.
• As the polysiloxane compound Average composition ratio R a S i 0 4 —
• R is a substituted or unsubstituted monovalent organic group, for example, a methyl group, an ethyl group, a propyl group, a vinyl group, a phenyl group, or a halogen-substituted hydrocarbon thereof.
• a is a number greater than 0 and less than 4, preferably from 1.800 to 2.500, particularly preferably from 1.900 to 2.002.
• Polyorganosiloxane compounds having the formula (1) are used. Polysiloxane compounds are mainly linear compounds, but some may form a branched or three-dimensional structure, and may be homopolymers or copolymers. It may be a combination or a mixture thereof.
• the degree of polymerization of the polyorganosiloxane having the above average composition ratio is preferably from 3 to 10,000, and 2, (! To 10,000 can reduce the occurrence of bleed during processing of the product. , More preferred.
• the polyorganosiloxane having the above average composition ratio is terminated with a trimethylsilyl group, a dimethylvinylsilyl group, a triphenylsilyl group, or the like at the end of the molecular chain.
• Those which are blocked with a trimethylsilyl group are particularly preferred because they have a small adverse effect on the polymerization activity.
• the molecular weight of the polysiloxane compound there is no particular limitation on the molecular weight of the polysiloxane compound, but it is easy to perform operations such as solid separation or slurry washing, preventing the contamination of the product polymer with the polysiloxane and separating. From the viewpoint of reusing the obtained polysiloxane, those which can be dissolved in the polymerization medium are preferable.
• the method for adding the polysiloxane to the reactor is not particularly limited as long as it can be uniformly dispersed in the polymerization solution. If it is a liquid such as silicone oil, it may be added directly or mixed with any of the polymerization feeds and supplied. Materials with poor fluidity, such as raw rubber, can be dissolved in a solvent or dissolved in one of the polymerization feeds beforehand and supplied in the same manner as for silicone oil. it can.
• the polysiloxane compound is preferably used in the polymerization medium in the range of 0.1 to 5,000 ppm, more preferably 1 to 5 ppm. Further, the amount of the copolymer to be formed is preferably in the range of l to 50,000 Gppm (preferably, more preferably 10 to 5,000 Gpm). The greater the amount of polysiloxane added, the greater the anti-adhesion effect.However, if the amount is too large, it will affect the polymerization reaction. Because of the adverse effects, the maximum amount of addition depends on the allowable residual amount of polysiloxane in accordance with the intended use of the product, and on the removal capacity of the equipment if a facility for removing polysiloxane is installed. It is determined. As the washing equipment, those generally installed to remove residual media, by-products, unreacted monomers and the like in the copolymer can be used. The minimum amount is set according to the adhesion of the polymer to be produced.
• composition ratio of the ethylene-one-olefin copolymer is determined by NMR, a calibration curve is created by infrared analysis, and the composition of the copolymer is determined based on the calibration curve. I asked.
• the amount of double bonds in the copolymer was measured by infrared spectroscopy, and the iodine value was determined.
• the catalyst used in the examples was prepared by the following method.
• DaVisQn 952 silica gel (Fujidevoso), which was heated sufficiently at 4 QQ ° C for 10 hours to remove water, was then dried on 5 Separa Brusco, which had been thoroughly dried and purged with nitrogen. 6 g was added, and hexane was added to obtain a slurry of 4. Further, while stirring the mixture at a rotation speed of 6 rpm, a solution of getyl aluminum monochloride adjusted to 3 mol Z with a hexane solvent 212.? ml was added dropwise over 35 minutes. Thereafter, stirring was continued for 2 hours at a rotation speed of 150 rpm.
• Degree of polymerization approx. 5,000 c: dimethylsiloxane z copolymer of methylvinylsiloxane (molar ratio: 99Z1) Degree of polymerization-approx. 5,000 D: dimethylsiloxane N-methyl-1,1-, 1-trifluoro mouth copolymer of propyl siloxane (molar ratio 9QZ 10)
• Viscosity 500,000 cSt B2: Homopolymer of dimethyl siloxane
• Viscosity 100, HO cSt B 3: Homopolymer of dimethyl siloxane
• Viscosity 1,000 cStB5: Homopolymer of dimethyl siloxane
• Triethyl aluminum (TEAL) of O.lg was diluted with normal hexane as an organic aluminum and injected into the catalyst supply pipe of this autoclaved catalyst.
• Li ? Diluted B.O.g was diluted with normal hexane and injected, and 450 g of dried propylene solution was injected to make the whole amount autoclaved.
• a small vessel with a capacity of 70 cc was filled with hydrogen, and the vessel was ventilated to reduce the pressure difference to 7 kg Z cnf. Then, 300 NL of ethylene was injected through a flow meter. The temperature of the autoclave was kept at 35 ° C by an external jacket.
• the copolymer was polymerized in the same manner as in Example 1 except that triethyl aluminum and silicone were not separately mixed and each was supplied alone.
• the shape of the polymer was observed in the same manner as in Example 1. However, no adhesion to the wall surface or the stirring blade was observed, and the obtained polymer was in the form of spherical particles.
• Table 1 shows the properties of the obtained copolymer.
• a copolymer was obtained in the same manner as in Example 1 except that the charged amounts shown in Table 1 were used, and the shape and properties of the copolymer were examined in the same manner, and the results are shown in Table 1. did.
• Reaction product of N-tallow-1,3-diaminopropane and epichlorohydrin in a molar ratio of 1: 1.5 1.3.3% by weight of dodecinolebenzen Snorrephonic acid is a substance consisting of 7.4% by weight.
• a copolymer was obtained in the same manner as in Example 1 except that 5-ethylidene-2-norbornane (ENB) was used and the amounts charged were as shown in Table 1.
• ENB was purified and dehydrated by simple distillation in advance, and added after injection of 300 NL of ethylene.
• the adhesion and shape of the copolymer to the vessel wall were observed in the same manner as in Example 1, but there was no adhesion to the wall surface and the stirring blade, and the obtained polymer was in the form of spherical particles. there were.
• Table 1 shows the properties of the obtained copolymer.
• a copolymer was obtained in the same manner as in Example 12 except that silicone was not used, and the shape and properties of the copolymer were similarly examined. The results are shown in Table 1. However, the obtained copolymer was in a lump and adhered to the inner wall surface and the stirring blade. Examples 13 and 14
• a copolymer was obtained in the same manner as in Example 1 except that the polymerization temperature was changed to 40 ° C, and the amounts of hydrogen and ethylene added were changed to the respective amounts shown in Table 1. , And similarly The shape and properties of the polymer were examined, and the results are shown in Table 1.
• the polymerization temperature was kept at 30 ° C by controlling the cooling amount of the jacket. Forty minutes after the start of the polymerization, a small amount of methanol was added to stop the polymerization reaction.
• the resulting port Li Ma one is 75 g arm twelve viscosity comprises 65 wt% of ethylene-les emissions at the ML i + 4 (100 ° C ) 9 (I der is, Po Li on the wall and ⁇ deposition of mer is not observed, the copolymer was Tsu because in granular 0
• a copolymer was obtained in the same manner as in Example 15 except that silicone was not used.
• the resulting polymer is 52 g, contains 3% by weight of ethylene, and has a ML of 4 (100 ° C). However, the polymer of g was attached to the wall surface and the stirring blade in a lump.
• the supply of the raw material to the reactor is performed at a predetermined rate of propylene 35 / hour (the molar ratio of ethylene propylene in the gas phase in the reactor is 2.5 to 2.6.
• the mixture was cooled to -10 to -5 ° C, and hydrogen, TEAL and silicone were mixed in a pipe and supplied.
• the 3 ⁇ catalyst was injected directly into the reactor by a pump as a slurry suspended in a solution of £ 0 [0] ⁇ 4 in normal hexane.
• the polymerization temperature was maintained at 35 ° C by adjusting the temperature of the refrigerant in the reactor jacket.
• Copolymers were obtained by continuous polymerization in the same manner as in the examples except that ENB was used and the charge amounts shown in Table 2 were used.
• the raw material was supplied to the reactor by mixing 35 hours of propylene with a predetermined amount of ethylene, cooling to -10 to -5 ° C, and adding hydrogen, 9
• Example 24 Continuous operation was performed in the same manner as in Example 2 except that silicone was not added. However, the violent adhesion caused a clogging trouble in a short time. The raw rubber roll processability of the copolymer obtained in this comparative example was examined, and the result was determined to be “excellent”.
• Example 24
• the polymerization temperature depends on the adjustment of the jacket refrigerant flow and the self-flow.
• the temperature was kept at 30 ° C by adjusting the cooling amount of the shingling.
• the monomer composition is adjusted by adjusting the ethylene supply rate so that the ethylene / propylene ratio in the gas phase in the reactor is constant.
• the molecular weight is adjusted by adjusting the molecular weight.
• the hydrogen supply rate was adjusted so that the hydrogen concentration in the gas phase of the reactor was kept constant.
• a copolymer was obtained in the same manner as in Example 24 except that silicone was not added.
• Example 8 ⁇ 2 0.04 300 450 6 0 0.08 0.3 64 55.8 0 No adhesion, granular
• Example 9 ⁇ 3 U.U4 300 450 0 U U.Uo U * J 4o a bU.o u D
• Example 16 A 2 0 5.5.1.0 .4 28 85 0 54
• Example 19 B 0.5 0 3.0 0.4 0.9 27 75 0 54
• Example C 0 3.3 0.6 0.9 27 82 0 48 CO
• Example 21 B2 0 3.3 0.6 0.9 27 85 0 48 CO
• Example 22 A 0 2.75 0.5 0.7 26 85 0 48
• the coating has almost no effect on the polymerization activity of the catalyst and the physical properties of the produced polymer, and the formation of a polysiloxane coating layer on the inner wall of the reactor, etc. In addition, it can be prevented. Therefore, a slurry polymerization method using at least one transition metal-based catalyst of V, Zr and Hf, which has been practically impossible due to the conventional furling method, This makes it possible to industrially produce a rubber-like ethylene copolymer.

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• 1990
  • 1990-06-12 JP JP2153484A patent/JPH0445110A/ja active Pending
• 1991
  • 1991-06-10 KR KR1019910009494A patent/KR920000802A/ko not_active Withdrawn
  • 1991-06-11 CN CN91104055A patent/CN1057272A/zh active Pending
  • 1991-06-12 WO PCT/JP1991/000783 patent/WO1991019747A1/ja not_active Ceased
  • 1991-06-12 EP EP91911188A patent/EP0535230A1/en not_active Withdrawn
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