KR101758572B1 - Method for transition of incompatible catalysts in polymerization - Google Patents

Abstract

The present invention relates to a method for converting between polymerization catalyst systems which are incompatible with each other, and more particularly to a method for converting an olefin polymerization reaction using a Ziegler Natta catalyst to an olefin polymerization reaction using a metallocene catalyst.
According to the present invention, excessive hydrogen is added at the beginning of the metallocene polymerization operation without introducing the deactivation agent or activator during the conversion process, thereby shortening the time required for the conversion process between the incompatible catalyst systems, The resulting polymerized product can be obtained.

Description

METHOD FOR TRANSMISSION OF INCOMPATIBLE CATALYST IN POLYMERIZATION < RTI ID = 0.0 >

The present invention relates to a method for converting between mutually immiscible polymerization catalyst systems, and more particularly to a method for converting from an olefin polymerization reaction using a Ziegler-Natta catalyst system to an olefin polymerization reaction using a metallocene catalyst system.

Ziegler - Natta catalysts and metallocene catalysts, which are known as catalysts for producing polyolefins, are in a mutually incompatible relationship. This is because the hydrogen reactivity between the Ziegler-Natta catalyst and the metallocene catalyst shows a significant difference in the comonomer reactivity.

In particular, in the case of hydrogen-reactive, the metallocene catalyst is 100 to 600 times more prevalent than the Ziegler-Natta catalyst, so that in the presence of a Ziegler-Natta catalyst under the operating conditions of conventional metallocene catalysts, the Ziegler- To cause serious gel problems in the product.

In order to avoid such problems, a method for conversion between mutually immiscible polymerization catalyst systems, in particular a conventional method for conversion from a Ziegler-Natta catalyst to a metallocene catalyst, comprises reacting an inert agent Is associated with the use of. Deactivation agents that can be used in these catalytic conversion processes are divided into reversible and irreversible deactivators.

In the case of the reversible inactivating agent, it can be relatively easily removed in the reactor as compared with the irreversible inactivating agent, thereby shortening the time required for the operation switching. However, the use of alkylaluminum component removers such as TEAL for the removal of the reversible inactivating agent may lead to the re-activation of the Ziegler Natta residual catalyst, from which the activity has been removed, thereby creating a gel in the product. On the other hand, if removal through only venting is performed in order to prevent gel formation, a trace amount of deactivating agent and a metallocene catalyst are bonded and deteriorated, and there is a possibility of gel formation by a metallocene catalyst.

In the case of the irreversible inactivating agent, unlike the reversible inactivating agent, the use of the alkylaluminum component removing agent such as TEAL for the removal of the deactivating agent is not likely to reactivate the inactivated Ziegler Natta residual catalyst, but is easily removed in the reactor The time required for conversion is long.

Therefore, there is a need to develop an efficient conversion method between mutually immiscible catalyst systems.

It is an object of the present invention to provide a method for efficiently switching between an incompatible polymerization catalyst capable of shortening the time required for the conversion process between the incompatible polymerization catalyst systems and producing a polymerization product free from gel problems.

Another object of the present invention is to provide a polymerization product in which gel problems are solved by applying the above-mentioned efficient conversion method between immiscible polymerization catalysts.

In order to achieve the above object, the present invention provides a method for converting from a polymerization reaction by a first catalyst to a polymerization reaction by a second catalyst which is immiscible with the first catalyst, comprising the steps of: a) ; b) terminating the polymerization reaction with the first catalyst; c) introducing a reversible inactivating agent; d) removing said deactivating agent through nitrogen ventilation; e) introducing hydrogen in an amount of 10 to 30 times the amount of hydrogen supplied to produce the olefin polymer melt index of 1 g / 10 min of said second catalyst, and establishing polymerization conditions using said second catalyst; And f) introducing a second catalyst; g) reducing the amount of hydrogen input to an amount of hydrogen input to produce an olefin polymer melt index of 0.5 to 10 g / 10 min of the second catalyst, and continuing the second catalytic polymerization. to provide.

According to a preferred embodiment of the present invention, the first catalyst comprises a Ziegler Natta catalyst, and the second catalyst may comprise a metallocene catalyst.

According to a preferred embodiment of the present invention, the step of stopping the supply of the first catalyst in the step b), and then maintaining the polymerization conditions for 1 to 10 hours may be further included.

According to a preferred embodiment of the present invention, the amount of the reversible deactivating agent in step c) may be 5 to 20 molar ratio with respect to the total metal atoms present in the reactor.

According to a preferred embodiment of the present invention, the step (d) may further include a step of maintaining the deactivating agent for 5 to 10 hours while flowing or stirring the deactivating agent.

According to a preferred embodiment of the present invention, the step (e) may further comprise the step of maintaining the hydrogen input amount for 0.5 to 2 times the internal product retention time.

According to a preferred embodiment of the present invention, the step g) may further comprise: h) judging whether or not the conversion from the polymerization reaction using the first catalyst to the polymerization reaction using the second catalyst is performed.

According to the present invention, excessive hydrogen is added at the beginning of the second catalytic polymerization operation without adding the deactivation agent or activator during the conversion from the polymerization reaction using the first catalyst to the polymerization reaction using the second catalyst, It is possible to shorten the time for the conversion step between the conversion catalyst systems and to obtain a polymerization product in which problems such as gel generation and the like are solved.

Fig. 1 is a process diagram of a gas phase polymerization reaction.

The present invention provides an efficient method for operating conversion between mutually immiscible catalyst systems.

A preferred example of the present invention is a method for converting a reactor for synthesizing a polymer using a first catalyst into a reactor for synthesizing a polymer using a second catalyst and converting it to a minimum required time, comprising the steps of vapor phase, liquid phase, slurry, Can be used. Especially suitable for gas phase polymerization processes in fluidized reactors.

Specifically, after the completion of the first catalyst operation, the first catalyst is deactivated using a reversible deactivation agent and the deactivation agent is removed only by nitrogen ventilation without addition of a remover. When the reactor conditions for the second catalyst operation are established, the hydrogen is supplied in excess to the normal second catalyst operating condition, and the hydrogen input amount is changed in a normal operating condition after a predetermined time.

Hereinafter, preferred embodiments of the present invention will be described in detail. In a preferred example of the present invention, a Ziegler-Natta catalyst is used as the first catalyst and a metallocene catalyst is used as the second catalyst.

≪ First catalyst: Ziegler-Natta catalyst >

In one example of the present invention, the Ziegler-Natan catalyst, which is the first catalyst, may be a conventional Ziegler-Natta catalyst used in the polymerization process. The Ziegler-Natta catalysts used in the present invention include, for example, organometallic compounds of Group 1 or 2 metals, typically trialkylaluminums, which are used as activators for transition metal halides and transition metal halides such as titanium or vanadium halides do.

The Ziegler-Natta catalyst may comprise alkyl aluminum or internal electron donors complexed to the transition metal. The transition metal halide is either supported or complexed to the magnesium compound. The active Ziegler Natta catalyst may be impregnated on an inorganic support such as silica or alumina. Further details of conventional Ziegler Natta catalysts are disclosed in U.S. Patent Nos. 3687920, 4086408, 4376191, 5019687, 4101445, 4560671, 4719193, 4755495, 5070055.

≪ Second catalyst: metallocene catalyst >

In one example of the present invention, the metallocene catalyst, which is the second catalyst, has the following constituents.

(a) a main catalyst mixture comprising a metallocene compound represented by the following general formula (1) or (2)

(b) a promoter comprising a Bulky compound which reacts with an aluminoxane compound or an organoaluminum compound or a metallocene compound to have catalytic activity,

(c) a support for supporting the main catalyst mixture and the cocatalyst

In the component (a), one or more of the following formulas (1) and (2) may be selected.

In Formula 1,

M is a Group 3 to 10 element in the periodic table, preferably a Group 4 element in the periodic table.

Ar ¹ and Ar ² may be the same or different and are each independently a ligand having a cyclopentadienyl skeleton, such as a cyclopentadienyl group, an indenyl group, a tetrahydroindenyl group, A fluorenyl group and the like and each independently represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkylsilyl group, a silylalkyl group, a haloalkyl group, A cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an arylalkyl group, an alkylaryl group, an arylsilyl group, a silylaryl group, ) Group or a halogen group as a substituent, or may form a ring by a bond between substituents.

X is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, an alkylsilyl group, a silylalkyl group, an aryl group having 6 to 20 carbon atoms, an arylalkyl group, an alkylaryl group, an arylsilyl group, a silylaryl group, An alkylsiloxy group, an aryloxy group having 6 to 20 carbon atoms, a halogen group, and an amine group,

n is an integer of 1 to 5 and varies depending on the oxidation number of the central metal.

(2) include, but are not limited to, bis (cyclopentadienyl) zirconium dichloride, bis (methylcyclopentadienyl) zirconium dichloride, bis (1,3-dimethylcyclopentadienyl) zirconium (Ethylcyclopentadienyl) zirconium dichloride, bis (isopropylcyclopentadienyl) zirconium dichloride, bis (n-butylcyclopentadienyl) zirconium dichloride, bis (isobutylcyclopentadienyl) zirconium dichloride, bis Zirconium dichloride, bis (indenyl) zirconium dichloride, bis (1-butyl-3-methylcyclopentadienyl) zirconium dichloride, bis (pentamethylcyclopentadienyl) zirconium dichloride, bis Zirconium dichloride, bis (4,5,6,7-tetrahydro-1-indenyl) zirconium dichloride, bis (n-butylcyclopentadienyl) zirconium dichloride, Is a ligand-free metallocene compound linking a cyclopentadienyl ring selected from the group comprising dichloride.

In Formula 2,

M is a Group 3 to 10 element in the periodic table, preferably a Group 4 element in the periodic table.

Ar ¹ and Ar ² may be the same or different from each other and each independently represents a ligand having a cyclopentadienyl skeleton, such as a cyclopentadienyl group, an indenyl group, a tetrahydroindenyl group, a fluorenyl group, etc., An alkyl group having 1 to 20 carbon atoms, an alkylsilyl group, a silylalkyl group, a haloalkyl group, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an arylalkyl group, an alkylaryl group, an arylsilyl group, Group may be a substituent, and a ring may be formed by a bond between substituents.

B is a component which does not directly coordinate to the transition metal M but connects the ligands Ar ¹ and Ar ^{2 and} can be selected from carbon (C), silicon (Si), germanium (Ge), nitrogen (N) And may be substituted with R.

R is hydrogen or an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, an alkylsilyl group, a silylalkyl group, an aryl group having 6 to 20 carbon atoms, an arylalkyl group, an alkylaryl group, an arylsilyl group, a silylaryl group or a hydrogen atom, It depends on the kind of B, and is 1 or 2.

The above formula (2) includes, but not limited to, but not limited to, rac-ethylene bis (1-indenyl) zirconium dichloride, rac- ethylene bis (1-indenyl) hafnium dichloride, rac- Tetrahydroindenyl) zirconium dichloride, rac-ethylene bis (1-tetrahydroindenyl) hafnium dichloride, rac-dimethylsilanediylbis (2-methyl-tetrahydrobenzenylenyl) zirconium dichloride, rac -Dimethylsilanediylbis (2-methyl-tetrahydrobenzenylenyl) hafnium dichloride, rac-diphenylsilandiylbis (2-methyl-tetrahydrobenzenylenyl) zirconium dichloride, rac- Dimethylsilandiylbis (2-methyl-4,5-benzindenyl) zirconium dichloride, rac-dimethylsilanediylbis (2-methyl-tetrahydrobenzenylidene) hafnium dichloride, -Methyl-4,5-benzindenyl) hafnium dichloride Diphenylsilanediylbis (2-methyl-4,5-benzindenyl) zirconium dichloride, rac-diphenylsilandiylbis (2-methyl-4,5-benzindenyl) hafnium di (2-methyl-5,6-cyclopentadienylindenyl) zirconium dichloride, rac-dimethylsilanediylbis (2-methyl-5,6-cyclopentadienyl Diphenylsilanediylbis (2-methyl-5,6-cyclopentadienylindenyl) zirconium dichloride, rac-diphenylsilandiylbis (2-methyl-5,6 (2-methyl-4-phenylindenyl) zirconium dichloride, rac-dimethylsilylbis (2-methyl-4-phenylindenyl) hafnium dichloride, ) Hafnium dichloride, rac-diphenylsilylbis (2-methyl-4-phenylindenyl) zirconium dichloride, rac-diphenylsilylbis Lee (Cyclopentadienyl) hafnium dichloride, diphenylmethylidene (cyclopentadienyl) (9-fluorenyl) zirconium dichloride, isopropylidene (cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylidene (cyclopentadienyl) (9-fluorenyl) hafnium dichloride, iso-propylidene (3-methylcyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylidene (3-methylcyclopentadienyl) (9-fluorenyl) zirconium dichloride, iso-propylidene (3-methylcyclopentadienyl) (Cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylsilyl ((cyclopentadienyl) zirconium dichloride), diphenylmethylidene (3-methylcyclopentadienyl) Cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethyllithium (Cyclopentadienyl) (2,7-di-tert-butylfluorene-9-yl) zirconium dichloride, diphenylmethylidene (cyclopentadienyl) (3-tert-butylcyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) zirconium dichloride, diphenylmethylidene Butyl-cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, diphenylmethylidene (3-tert- butyl-5-methylcyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) zirconium dichloride, diphenylmethylidene (3-tert- butyl- (9-fluorenyl) zirconium dichloride, 1,2-ethylene bis (9-fluorenyl) hafnium dichloride, rac- [1, 2-bis (9-fluorenyl) -1-phenyl-ethane] zirconium dichloride, ethane] hafnium dichloride, [1- (9-fluorenyl) -2- (5,6-cyclopenta- 2-methyl Ethane] zirconium dichloride, [1- (9-fluorenyl) -2- (5,6-cyclopenta-2-methyl-1-indenyl) [(4- (fluorenyl) -4,6,6-trimethyl-2-phenyl-tetrahydropentrene] zirconium dichloride, [4- (fluorenyl) (2-phenyl-cyclopentadienyl) (9-fluorenyl) zirconium dichloride, iso-propylidene (2-phenyl-cyclopentadienyl) (2-phenyl-cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2-phenyl-cyclopentadienyl) 9-fluorenyl) hafnium dichloride, isopropylidene (2-phenyl-cyclopentadienyl (2,7-di-tert-butylfluorene-9-yl) zirconium dichloride, isopropylidene (2-phenyl-cyclopentadienyl) (2-phenyl-cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) zirconium dichloride, diphenylmethylidene (2-phenyl- (Fluorenyl) -4,6,6-trimethyl-2- (p-tolyl) -cyclopentadienyl) (2,7- -Tetrahydropentrene] zirconium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2- (p- tolyl) -tetrahydropentrene] hafnium dichloride, [isopropylidene- Cyclopentadienyl) - (9-fluorenyl)] zirconium dichloride, [isopropylidene- (2- (p- tolyl) -cyclopentadienyl) - 4- (fluorenyl) -4,6,6-trimethyl-2- (m-tolyl) -tetrahydro-penta ] Zirconium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2- (m-tolyl) -tetrahydropentrene] hafnium dichloride, [isopropylidene (2- ) - cyclopentadienyl) - (9-fluorenyl)] zirconium dichloride, [isopropylidene (2- (m- tolyl) -cyclopentadienyl) - (9-fluorenyl)] hafnium dichloride , [Diphenylmethylidene (2- (m-tolyl) -cyclopentadienyl) - (9-fluorenyl)] zirconium dichloride, (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, [isopropylidene (2- (m-tolyl) -cyclopentadienyl) ] Zirconium dichloride, [isopropylidene (2- (m-tolyl) -cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl)] hafnium dichloride, [diphenylmethylidene (2,7-di-tert-butylfluoren-9-yl)] zirconium dichloride (2- (m-tolyl) -cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl)] hafnium dichloride, [4- (fluorenylidene) cyclopentadienyl] ) -4,6,6-trimethyl-2- (o-tolyl) -tetrahydropentrene] zirconium dichloride, [4- (fluorenyl) ) -Tetrahydropentrene] hafnium dichloride, [isopropylidene (2- (o-tolyl) -cyclopentadienyl) (9-fluorenyl)] zirconium dichloride, [isopropylidene (2- (9-fluorenyl)] hafnium dichloride, [4- (fluorenyl) -4,6,6-trimethyl- 2- (2,3-dimethylphenyl) -tetra (Fluorenyl) -4,6,6-trimethyl-2- (2,3-dimethylphenyl) -tetrahydropentrene] hafnium dichloride, [4- (fluorenyl) (2,4-dimethylphenyl) -tetrahydro-pentalene] zirconium dichloride, [4- (fluorenyl) - (2,4-dimethylphenyl) -tetrahydropentrene] zirconium dichloride, [isopropylidene (2- (2,3-dimethylphenyl) -cyclopentadienyl) ( (9-fluorenyl)) hafnium dichloride, [isopropylidene (2 (2,3-dimethylphenyl) -cyclopentadienyl) Cyclopentadienyl) (9-fluorenyl)] zirconium dichloride, [isopropylidene (2- (2,3-dimethylphenyl) -cyclopentadienyl) (9 -Fluorenyl]) hafnium dichloride, [diphenylmethylidene (2- (2,3-dimethylphenyl) -cyclopentadienyl) (9-fluorenyl)] zirconium dichloride, diphenylmethylidene Cyclopentadienyl) (9-fluorenyl)] hafnium dichloride, [diphenylmethylidene (2- (2,4-dimethylphenyl) -cyclopentadienyl) (9-fluorenyl)] zirconium dichloride, [diphenylmethylidene (2- (2, Cyclopentadienyl) (9-fluorenyl)] hafnium dichloride, [isopropylidene (2- (2,3-dimethylphenyl) -cyclopentadienyl) (2,2-di-tert-butylfluorene-9-yl)] zirconium dichloride, [isopropylidene (2- (2,3- dimethylphenyl) -cyclopentadienyl) 9-yl)] hafnium dichloride, [isopropylidene (2- (2,4-dimethylphenyl) -cyclopentadienyl) (2,7-di-tert- butylfluoren-9-yl)] zirconium di (2,7-di-tert-butylfluoren-9-yl)] hafnium dichloride, [diphenylmethylidene (diphenylmethylidene) (2,2-di-tert-butylfluoren-9-yl)] zirconium dichloride, [diphenylmethylidene (2- (2,3- dimethylphenyl) cyclopentadienyl) Dimethylphenyl) cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl)] hafnium dichloride, diphenylmethylidene (2- Dimethylphenyl) cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl)] zirconium dichloride, diphenylmethylidene (2- (2,4- Yl)] hafnium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2- (2,6-dimethylphenyl) ) - tetrahydropentalene] zirconium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2- (2,6- dimethylphenyl) -tetrahydropentrene] hafnium dichloride, [4 - (fluorenyl) -4,6,6-trimethyl-2- (3,5-dimethylphenyl) -tetrahydropentrene] zirconium dichloride, [4- (fluorenyl) Tetramethylphenyl) tetrahydropentene] hafnium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2-tetramethylphenyl-tetrahydropentrene] zirconium Tetramethylphenyl-tetrahydropentene] hafnium (4-fluorenyl) -4,6,6-trimethyl-2- (2,4-dimethoxyphenyl) -tetrahydropentrene] zirconium dichloride, [4- (fluorenyl) -4 (3, 6-trimethyl-2- (2,4-dimethoxyphenyl) -tetrahydropentrene] hafnium dichloride, [4- (fluorenyl) Dimethoxyphenyl) -tetrahydropentrene] zirconium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2- (3,5- (Fluorenyl) -4,6,6-trimethyl-2- (chlorophenyl) -tetrahydropentrene] zirconium dichloride, [4- (fluorenyl) 2- (fluorophenyl) -tetrahydro-pentalene] hafnium dichloride, [4- (fluorenyl) -4,6,6-trimethyl- 2- (fluorophenyl) Zirconium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2- (fluorophenyl) -tetrahydro-penta (4-fluorenyl) -4,6,6-trimethyl-2- (difluorophenyl) -tetrahydropentrene] zirconium dichloride, [4- (fluorenyl) , 6,6-trimethyl-2- (difluorophenyl) -tetrahydropentrene] hafnium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2- (pentafluorophenyl) ) - tetrahydropentalene] zirconium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2- (difluorophenyl) -tetrahydropentrene] hafnium dichloride, [4- Fluorenyl) hafnium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2 (tert- butylphenyl) - (3,5-trifluoromethyl-phenyl) -tetrahydropentrene] zirconium dichloride, [4- (fluorenyl) -4,6,6-trimethyl- 2- (3,5- Methyl-phenyl) -tetrahydro-pentalene] hafnium dichloride, [4- (fluorenyl) -4,6,6-trimethyl (3,5-di-tert-butylphenyl) tetrahydropentrene] zirconium dichloride, [4- (fluorenyl) -4,6,6- Tetrapropylenesulfonium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2- (biphenyl) -tetrahydropentrene] zirconium dichloride, [4- (Fluorenyl) -4,6,6-trimethyl-2- (biphenyl) -tetrahydropentrene] hafnium dichloride, [4- (fluorenyl) (Fluorenyl) -4,6,6-trimethyl-2-naphthyl-tetrahydropentene] hafnium dichloride, [4- (fluorenyl) -4,6,6-trimethyl-2- (3,5-diphenyl-phenyl) -tetrahydro-pentalene] zirconium dichloride, [4- (fluorenyl) (3,5-diphenyl-phenyl) -tetrahydropentrene] hafnium dichloride, isopropylidene (2-tetramethylphenyl-cyclo Zirconium dichloride, isopropylidene (2- (2,6-dimethylphenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, isopropylidene ( Cyclopentadienyl) (9-fluorenyl) zirconium dichloride, isopropylidene (2- (2,4-dimethoxyphenyl) -cyclopentadienyl) (9 Zirconium dichloride, isopropylidene (2- (3,5-dimethoxyphenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, (9-fluorenyl) zirconium dichloride, isopropylidene (2- (2,6-dimethoxyphenyl) -cyclopentadienyl) (9-fluorenylidene) ) Zirconium dichloride, isopropylidene (2- (dichlorophenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, isopropylidene (9-fluorenyl) zirconium dichloride, isopropylidene (2- (fluoro) -cyclopentadienyl) zirconium dichloride, isopropylidene (2- (trichlorophenyl) Phenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, isopropylidene (2- (difluorophenyl) cyclopentadienyl) (9-fluorenyl) zirconium dichloride, isopropyl (9-fluorenyl) zirconium dichloride, isopropylidene (2- (3,5-trifluoromethyl-phenyl) -cyclopentadienyl (cyclopentadienyl) Zirconium dichloride, isopropylidene (2- (tert-butylphenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, isopropylidene (2- Cyclopentadienyl) (9-fluorenyl) zirconium dichloride, isopropylidene (2- (biphenyl) -cyclophenyl) Zirconium dichloride, isopropylidene (2- (3,5-diphenyl-phenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, isopropylidene (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2-tetramethylphenyl-cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenyl (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2- (3,5-dimethylphenyl) -cyclopentadienyl) ) (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2- (2,4-dimethoxyphenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylidene Cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2- (2,3-dimethoxyphenyl) -cyclopentadienyl) (9- Zirconium dichloride, diphenylmethylidene (2- (2,6-dimethoxyphenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2- Phenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2- (dichlorophenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethyl (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2- (fluorophenyl) -cyclopentadienyl) (9-fluorenylidene) ) Zirconium dichloride, diphenylmethylidene (2- (difluorophenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2- (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2- (3,5-trifluoromethyl-phenyl) -cyclopentadienyl Zirconium dichloride, diphenylmethylidene (2- (tert-butylphenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2- Cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2- (biphenyl) -cyclopentadienyl) (9-fluorenyl) Zirconium dichloride, diphenylmethylidene (2- (3,5-diphenyl-phenyl) -cyclopentadienyl) (9-fluorenyl) zirconium dichloride, diphenylmethylidene (2- (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride (cyclopentadienyl) (9-fluorenyl) zirconium dichloride, isopropylidene (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, isopropylidene (2- (3,6-dimethylphenyl) -cyclopentadienyl) , 5-dimethylphenyl) -cyclopentane (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, isopropylidene (2- (2,4-dimethoxyphenyl) -cyclopentadienyl) Di-tert-butylfluorene-9-yl) hafnium dichloride, isopropylidene (2- (3,5- dimethoxyphenyl) cyclopentadienyl) Yl) hafnium dichloride, isopropylidene (2- (2,3-dimethoxyphenyl) -cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, Isopropylidene (2- (2,6-dimethoxyphenyl) -cyclopentadienyl) (2,7-di-tert- butylfluoren-9-yl) hafnium dichloride, isopropylidene (2- Phenyl) -cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, isopropylidene (2- (dichlorophenyl) cyclopentadienyl) Di-tert-butylfluorene-9-yl) hafnium dichloride, isopropylidene (2- (trichlorophenyl) -cyclopenta (2,7-di-tert-butyl-9-yl) hafnium dichloride, isopropylidene (2- (fluorophenyl) -cyclopentadienyl) Yl) hafnium dichloride, isopropylidene (2- (difluorophenyl) cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, isopropylidene (2- (pentafluorophenyl) cyclopentadienyl) Cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, isopropylidene (2- (tert- butylphenyl) -cyclopentadienyl Yl) hafnium dichloride, isopropylidene (2- (3,5-di-tert-butylphenyl) -cyclopentadienyl) (2, Di-tert-butylfluoren-9-yl) hafnium dichloride, isopropylidene (2- (biphenyl) Cyclopentadienyl) (2 (3,5-di-tert-butylfluoren-9-yl) hafnium dichloride, isopropylidene (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, isopropylidene (2-naphthyl-cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, diphenylmethylidene (2-tetramethylphenyl-cyclopentadienyl) Cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, diphenylmethylidene (2- (3,5-dimethylphenyl) Diphenylmethylidene (2- (2,4-dimethoxyphenyl) -cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, (Ditert-butylfluoren-9-yl) hafnium dichloride, diphenylmethylidene (2- (3,5-dimethoxyphenyl) Diphenylmethylidene (2- (2,3-dimethoxyphenyl) -cyclopentadienyl) (2, 3-dimethoxyphenyl) cyclopentadienyl) (2,6-dimethoxyphenyl) cyclopentadienyl) (2,7-di-tert-butyl) butylidene chloride, diphenylmethylidene (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, diphenylmethylidene (2- (chlorophenyl) -cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, diphenylmethylidene (2- (trichlorophenyl) -cyclopentadienyl) Cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, diphenylmethylidene (2- (fluorophenyl) (Tert-butylfluorene-9-yl) hafnium dichloride, diphenylmethylidene (2- (difluorophenyl) -cyclopene (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, diphenylmethylidene (2- (pentafluorophenyl) -cyclopentadienyl) (2,7-di-tert-butyl-phenyl) -cyclopentadienyl) (diphenylmethyl) diphenylmethylidene Yl) hafnium dichloride, diphenylmethylidene (2- (tert-butylphenyl) cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, Diphenylmethylidene (2- (3,5-di-tert-butylphenyl) cyclopentadienyl) (2,7-di-tert-butylfluorene-9-yl) hafnium dichloride, diphenylmethylidene (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, diphenylmethylidene (2- (3,5-diphenyl-phenyl) ) -Cyclopentadienyl) (2,7-di-tert-butylfluoren-9-yl) hafnium dichloride, diphenylmethylidene (2-naphthyl- Other cyclopentadienyl) (2,7-di-tert-butyl-fluoren-9-yl) hafnium dichloride metallocene compound is such that the ligand for connecting the cyclopentadienyl ring selected from the group comprising metal.

In the metallocene catalyst of the present invention, the mixed metallocene transition metal compounds include a promoter that causes polymerization activity, and the promoter is an aluminoxane compound having a structure represented by the following formula (3) or (4) and / or Aluminum compound.

In this formula,

R ¹ is an alkyl group having 1 to 10 carbon atoms,

q is an integer of 1 to 70;

In this formula,

R ² , R ³ and R ⁴ are the same or different and each is an alkyl group having 1 to 10 carbon atoms, an alkoxy group or a halogen group, and at least one of R ² , R ³ and R ⁴ is an alkyl group.

In this formula,

C is a proton-binding cation of a Lewis Base or a metal or non-metal compound having oxidizing power,

D is a compound of an organic substance and an element belonging to Groups 5 to 15 on the periodic table.

The compound represented by the above-mentioned general formula (3) may be used in combination with one or more compounds selected from the group consisting of methylaluminoxane, ethylaluminoxane, butylaluminoxane, hexylaluminoxane, octylaluminoxane, decylaluminoxane, And the like.

The compound represented by Formula 4 may be selected from the group consisting of trimethylaluminum, triethylaluminum, tributylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum, dimethyl But are not limited to, dimethylaluminum methoxide, diethylaluminum methoxide, dibutylaluminum methoxide, dimethylaluminum chloride, diethylaluminum chloride, dibutylaluminum chloride dibutylaluminum chloride, methylaluminum dimethoxide, ethylaluminum dimethoxide, butylaluminum dimethoxide, methylaluminum dichloride, ethylaluminum dichloride, It may be a fluoride (ethylaluminum dichloride), and butyl aluminum dichloride, at least one compound selected from group consisting of such as (butylaluminum dichloride).

The compound represented by the general formula (5) is preferably a compound selected from the group consisting of triphenylcarbenium tetrakis (pentafluorophenyl) borate, trimethylammonium tetraphenylborate, triethylammonium tetraphenylborate Tripropylammonium tetraphenylborate, tributylammonium tetraphenylborate, trimethylammonium tetrakis (pentafluorophenyl) borate, triethylammonium tetrakis (triphenylphosphine) borate, Triethylammonium tetrakis (pentafluorophenyl) borate, tripropylammonium tetrakis (pentafluorophenyl) borate, tributylammonium tetrakis (pentafluorophenyl) borate, Anilinium tetrakis (pentafluorophenyl) borate, anilinium tetraphenylborate, anilinium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate), pyridinium tetraphenylborate, pyridinium tetrakis (pentafluorophenyl) borate, (Pentafluorophenyl) borate, silver tetrakis (pentafluorophenyl) borate, silver tetraphenylborate, silver tetrakis (pentafluorophenyl) borate, Tris (pentafluorophenyl) borane, tris (2,3,5,6-tetrafluorophenyl) borane (tris (2,3,5,6-tetraf luorophenyl) borane, tris (2,3,4,5-tetraphenylphenyl) borane, and tris (3,4,5-trifluorophenyl) ) And boron (tris (3,4,5-trifluorophenyl) borane).

Further, the metallocene catalyst of the present invention comprises a main catalyst mixture component in which the metallocene compound is mixed and a support for supporting the cocatalyst.

≪ Inactivating agent >

In the present invention, the deactivating agent is a catalyst destroying agent or an inhibitor which deactivates the ability of the catalyst to polymerize the olefin. In general, inactivating agents are divided into two types, such as reversible and irreversible inactivating agents.

First, the reversible deactivating agent includes, for example, internal olefins such as carbon monoxide, carbon dioxide, and 2-butene, internal dienes such as 2-4 hexadiene, alkenes and butadiene, and the like. The reversible deactivating agent inhibits the catalytic activity and the polymerization reaction for a certain period of time, but after a certain time under the usual operating conditions, the catalyst is reactivated to continue the polymerization reaction.

The irreversible deactivation agent is a substance that irreversibly deactivates the ability of the catalyst to polymerize the olefin. Examples of the inert deactivator include water, oxygen, alcohol, glycol, phenol, ether, carbonyl compound (e.g., ketone, aldehyde etc.) , Amines, nitriles, nitric acid compounds, pyridine, and the like, but are not limited thereto.

<Remover or Activator>

The remover or activator in the present invention is an organometallic compound such as BX ₃ , R ₁ R ₂ Mg, ethylmagnesium, R ₄ CORMg, RCNR, ZnR ₂ , CdR ₂ , LiR, SnR ₄ Halogen, each R group is a hydrocarbon group which may be the same or different).

A more preferred organometallic compound is AlR _(3-n) X _n wherein R is alkyl or cycloalkyl of 1 to 30, preferably 1 to 10 carbon atoms, branched or linear, or hydride radical , X is halogen, and n is 0, 1, or 2).

The most preferred organometallic compounds are alkylaluminums such as triethylaluminum (TEAL), trimethylaluminum (TMAL), triisobutylaluminum (TIBA) and tri-n-hexylaluminum (TnHAL).

In the present invention, after the polymerization of the Ziegler-Natta catalyst, the removal of the remover or activator is not performed until the completion of the conversion to the metallocene catalyst.

<Polymerization Step>

The process of the present invention can be used in gas phase, liquid phase, slurry or bulk phase polymerization processes. In particular, a gas phase polymerization process in a fluidized bed reactor is preferred.

An example of a typical gas phase polymerization process in the art will be described with reference to FIG.

The gas flow including the monomer for polymer polymerization proceeds through the fluidized bed reactor (1 in FIG. 1) and the inner fluidized bed is formed and the polymerization reaction proceeds, and the gas containing the unused monomer in the polymerization reaction (2 in FIG. 1) The flow rises. The gas flow whose temperature has been raised by the polymerization reaction is transferred to the compressor (3 in Fig. 1) and the heat exchanger (4 in Fig. 1) and is controlled to a temperature level suitable for the polymerization reaction. The monomers, , Co-catalyst, etc., and circulates to the gas phase polymerization reactor. The catalyst components required for the polymerization are separately introduced directly into the reactor fluidized bed site, and the resulting polymer is discharged from the bottom of the inner fluidized bed. The gas phase polymerization process is preferably carried out at a temperature of from 60 to 120 DEG C, more preferably from 65 to 100 DEG C, even more preferably from 70 to 90 DEG C, and preferably from 2 to 40 atm, more preferably from 10 to 30 atm, Even more preferably from 15 to 25 atmospheres.

A method for switching between immiscible polymerization catalyst systems according to an example of the present invention includes the following steps. Here, the polymerization catalysts which are mutually immiscible with each other are exemplified by a Ziegler-Natta catalyst and a metallocene catalyst.

a) conducting a polymerization reaction using a Ziegler-Natta catalyst;

b) terminating the polymerization reaction with the Ziegler Natta catalyst;

c) introducing a reversible inactivating agent;

d) removing said deactivating agent through nitrogen ventilation;

e) introducing hydrogen in an amount of 10 to 30 times the amount of hydrogen input to produce the olefin polymer melt index of 1 g / 10 min of the metallocene catalyst, and establishing polymerization conditions using the metallocene catalyst;

f) introducing a metallocene catalyst; And

g) reducing the amount of hydrogen input to a hydrogen input to produce an olefin polymer melt index of 0.5 to 10 g / 10 min of the metallocene catalyst, thereby continuing the metallocene catalytic polymerization.

Here, the reversible inactivating agent is preferably carbon dioxide. It is preferable that the polymerization step is a gas phase process.

The above step a) is a polymerization reaction carried out under ordinary polymerization reaction conditions using a Ziegler-Natta catalyst.

According to one example, the polymerization reaction using the Ziegler-Natta catalyst in step a) is carried out under conditions of a reactor pressure of 15 to 25 kgf / cm 2, a reactor temperature of 70 to 90 ° C and an ethylene ratio of 20 to 50 mol% . &Lt; / RTI &gt;

In the step b), the supply of the Ziegler-Natta catalyst is stopped to stop the polymerization reaction. Further, in order to sufficiently exhaust the olefin polymerization ability of the residual catalyst in the reactor, it is preferable to maintain the polymerization conditions for 1 to 10 hours.

In the step c), the amount of the reversible deactivation agent is preferably 5 to 20 times the total number of moles of the metal element present in the reactor so as to achieve sufficient reversible deactivation of the residual catalyst in the reactor.

Maintaining the reactor at a temperature of 70 to 90 DEG C and a pressure in the reactor of 5 to 25 atm for 5 to 10 hours to achieve sufficient reversible deactivation of the residual catalyst in the reactor prior to step c) .

In order to sufficiently remove the deactivation agent in the reactor in the step d), the nitrogen ventilation proceeds to a process of repeating the pressurization and the depressurization, and the range of 20 to 1 atm is suitable. The criterion for the completion of the nitrogen ventilation is that the inactivating substance in the degassing gas is 1 mol ppm or less. In the deactivation agent removal step, a separate scavenger, such as the alkylaluminum component (TEAL, TIBA, TnHAL, etc.), does not provide the possibility of causing reactivation of the Ziegler Natta residual catalyst deactivated by the reversible deactivation agent.

No remover or catalyst activator (cocatalyst) is subsequently provided for the same reasons in steps d), e), f) and g) above.

According to one example, the polymerization reaction with the metallocene catalyst in step e) is carried out at a reactor pressure of 15 to 25 kgf / cm &lt; 2 &gt;, a reactor temperature of 70 to 90 DEG C and an ethylene ratio of 20 to 80 mol% Is preferably carried out under the above conditions.

The gas composition in step e) is preferably composed of ethylene alone or in combination with one or more monomers, hydrogen to control the melt index of the polymer, non-condensable inert gas.

In step e), alpha olefin monomers of ethylene and one or more monomers such as propylene, butene-1, pentene-1, hexene-1, octene-1, decene-1, styrene and cyclic and polycyclic olefins, Are suitably used. Preferably, the comonomer is an alpha-olefin having 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, even more preferably 4 to 10 carbon atoms.

The hydrogen in step e) has the role of regulating the melt index or molecular weight of the polymer, especially the reversible deactivation agent remaining in the reactor after nitrogen venting in step d) and the metallocene catalyst introduced in step f) To achieve the role of preventing the formation of gels, i.e., high molecular weight polymers, during the olefin polymerization in step g), the hydrogenation rate of the olefin polymer melt index of 1 g / 10 min at typical metallocene catalyst operating conditions, It is preferable to add 30 times the amount.

In step e), preferably at a temperature of from 60 to 120 캜, more preferably from 65 to 100 캜, even more preferably from 70 to 90 캜, and preferably from 2 to 40 atm, more preferably from 10 to 30 atm , And even more preferably from 15 to 25 atmospheres. This applies equally to steps f) and g) above.

The time for maintaining the hydrogen overload state in step e) is preferably 0.5 to 3 times, more preferably 0.5 to 2.5 times the reactor residence time of the product polymerized with the metallocene catalyst under typical operating conditions, Fold, and even more preferably 0.5 to 2 times. The residence time of the reactor is calculated by dividing the amount of product discharge per hour into the weight of product inside the reactor.

In step h) above, it is preferred that the hydrogen is changed to a hydrogen input amount which produces an olefin polymer melt index of 0.5 to 10 g / 10 min under a typical metallocene catalyst operating condition.

Further comprising, after step g), h) determining whether to switch from a polymerization reaction with a Ziegler-Natta catalyst to a polymerization reaction with a metallocene catalyst, which comprises reacting the product obtained in step a) ) &Lt; / RTI &gt; of the product. If the conversion process is successful, the gel content will be similar before and after the process, and if the conversion process fails, the gel content will be higher in the product of step g) than the product of step a). The present invention provides a technique for solving such a problem.

Hereinafter, preferred embodiments and comparative examples are provided to facilitate understanding of the present invention. However, the following examples are intended to illustrate the present invention without limiting it thereto.

[Example]

<Catalyst Preparation>

Toluene and n-hexane were purchased from Sigma-Aldrich for anhydrous grades as raw materials for the metallocene catalyst preparation, and then activated molecular sieves (Molecular Sieve, 4A) or an activated alumina layer to further dry. MAO (methylaluminoxane) was purchased from Albemarle Corporation using a 10% toluene solution (HS-MAO-10%). Silica used XPO2410 from Grace without any further treatment.

In addition, the metallocene compound bis (1-butyl-3-methyl-cyclopentadienyl) zirconium dichloride was obtained from Albemarle Co., (Indenyl) zirconium dichloride was purchased from Chemtura Organometallics GmbH and used without purification.

The metallocene catalyst was prepared by reacting 5.7 g of bis (1-butyl-3-methyl-cyclopentadienyl) zirconium dichloride and 5.2 g of bis (indenyl) zirconium dichloride in a glove box Weighed and placed in a flask. At room temperature, MAO solution (920 g) was slowly added to the metallocene compound and stirred for 1 hour. Silica (200 g) was taken out of the glove box and then placed in a 3 L glass reactor under nitrogen. Then, toluene was added to the reactor to lower the temperature of the slurry silica to 0 ° C, and then the mixed reaction solution of the catalyst and MAO was added slowly. After stirring for 1 hour, the temperature was raised to 70 ° C and the reaction was further continued for 6 hours. After the reaction was completed, the temperature was lowered to room temperature, stirring was stopped, and the toluene layer was separated and removed. N-hexane was added and washed three times. After vacuum drying, 300 g of a supported catalyst of free flowing powder (Bright Flowing Powder) was obtained. As a result of ICP analysis of the supported catalyst, Zr was 0.77 wt% and Al was 13.9 wt%.

In order to feed the catalyst into the process operation, 200 g of the above metallocene supported catalyst was diluted in 10 kg of well-dried mineral oil under a nitrogen atmosphere.

Ziegler-Natta catalysts were prepared by impregnating titanium chloride, magnesium chloride, and tetrahydrofuran (THF) complexes from a THF solution into a silica support. The silica was first dehydrated at 600 ° C to remove water and chemically treated with triethylaluminum (TEAL) to remove any remaining water. The catalyst was treated by adding tri-n-hexylaluminum (TnHAL) and diethylaluminum chloride (DEAC) in an isopentane solution and dried to produce the final Ziegler Natan catalyst. The final catalyst had a 1% titanium content, a DEAC / THF molar ratio of 0.26 and a molar ratio of 0.29 TnHAL / THF.

&Lt; Gas Phase Polymerization Method in Fluidized Bed &

The Ziegler-Natta catalyst and the metallocene catalyst prepared by the above-mentioned catalyst production method were prepared by using the gas phase polymerization reactor of FIG. 1, under the operating conditions shown in the following Table 1 in steps a) and g) Respectively.

Reaction conditions Ziegler Natta catalyst Metallocene catalyst Temperature (℃)
Pressure (kgf / cm ² )
Ethylene (mol%)
Hydrogen (mol%)
Comonomer (mol%)
Alkyl aluminum / ethylene (g / kg)
Bed weight (kg)
Bed stay time (hr)
Bad discharge rate (kg / hr)
Gas circulation rate (m / s)
MI (g / 10 min)
Density (g / ml) 85
22
35
4.2
12.3 (1-butene)
0.18 (TEAL)
42
6
7
0.35
One
0.923 85
22
62
0.015
1.7 (1-Hexene)
0
42
6
7
0.35
One
0.917

<Conversion step>

a) Ziegler appears  Catalyzed polymerization To carry out the reaction  step

The Ziegler-Natta catalyst polymerization operation was carried out under the conditions described in Table 1, and a sample for film molding was taken as a control group for confirming whether or not the drilling operation was successful.

b) Ziegler appears  Stopping the polymerization reaction using the catalyst

Exhausting the ability to polymerize the olefin of the remaining catalyst in the reactor by maintaining the polymerization conditions other than the disconnection of the Ziegler-Natta catalyst and the cocatalyst, wherein, in addition to stopping the introduction of the Ziegler-Natta catalyst and its cocatalyst (TEAL) , Pressure, gas composition, bed weight and gas circulation rate were maintained for 6 hours in the same condition as the previous step.

c) reversible The inactivating agent  Step of injecting

Carbon dioxide was injected in an amount of 10 times the total number of moles of metal atoms existing in the fluidized bed in the reactor. After injection of carbon dioxide, the gas circulation flow was maintained for 6 hours. During the process, the temperature was maintained at 85 ° C and the pressure was maintained at 22 kgf / cm ² .

d) reacting the compound of formula The inactivating agent  Steps to remove

Nitrogen pressurized ventilation of the gas phase fluidized bed reactor was performed 10 times at a pressure of 5 to 20 kgf / cm ² . Nitrogen ventilation took 3 hours and after nitrogen ventilation, less than 1 ppm of carbon dioxide was measured.

e) Metallocene  The conditions for polymerization reaction using a catalyst are established, and in particular, hydrogen is added in an excess amount relative to a normal level

The gas circulation flow in the reactor was set up under the metallocene operating condition shown in Table 1 except for hydrogen, which constitutes the composition of the gas circulation flow for the metallocene catalyst polymerization operation. For hydrogen, the gas composition was set at 0.3 mol%.

f) Metallocene  Introducing a catalyst; And

When the gas composition reaches the equilibrium state in the step e), the metallocene catalyst prepared in the catalyst preparation is introduced into the reactor to initiate the polymerization reaction. After the start of step f), the set gas composition was maintained to maintain 6 hours (one time of reactor residence time).

g) Metallocene  By reducing the amount of hydrogen input, Metallocene  Continuing the catalytic polymerization;

After the completion of the step f), the hydrogenation charge amount was adjusted to 0.015 mol% and the polymerization reaction was carried out under the metallocene operating conditions shown in Table 1 above. Samples for judging the success of the conversion process were taken at the time point when the cumulative amount of discharged product corresponds to twice the weight of the bed weight in the reactor after the initiation of this step.

The samples of step a) and step g) taken to determine success were subjected to film formation to measure the degree of gel inclusion. The film was formed using a plastic corder (Brabender). The degree of gel content was visually confirmed by the number of gels per 450 cm ² of the film. The results are shown in Table 2.

[Comparative Example 1]

In the conversion step, the operating conditions were the same as those of the example except that the composition of hydrogen was set to 0 mol% in step e). The results are shown in Table 2.

[Comparative Example 2]

In the conversion step, the operating conditions were the same as those of the example except that the composition of hydrogen was set to 0.015 mol% in step e). The results are shown in Table 2.

[Comparative Example 3]

In the conversion step, the same procedure as in Comparative Example 2 was carried out except that the sample was sampled at a point in time when the cumulative amount of discharged products in the step g) corresponded to the weight of three times the weight of the bed in the reactor. The results are shown in Table 2.

[Comparative Example 4]

In the conversion step, the same procedure as in Comparative Example 2 was carried out except that the sample was sampled at a point in time when the cumulative amount of discharged products in the step g) corresponded to the weight of five times the weight of the bed in the reactor. The results are shown in Table 2.

Example Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Step e)
: Hydrogen composition (mol%) 0.3 0 0.015 0.015 0.015 Step g)
: Sampling point (cumulative production discharge / bed weight) 2 2 2 3 5 Number of gels (EA) Step a) 0 0 0 0 0 Step g) 0 100 or more 50 42 19

Unlike Comparative Examples 1 to 4, under the condition of no conversion of the deactivation agent or activator during the conversion process and during the metallocene polymerization operation, the gas phase composition for the metallocene operation and the hydrogenation at the beginning of the metallocene polymerization operation It can be seen that the polymerization product in which the gel problem is solved in the case of the excessive amount can be obtained while producing a small amount of the non-genuine product in a comparatively short time.

1: Fluidized bed reactor
2: reactor top
3: Compressor
4: Heat exchanger

Claims (15)

A method for converting from a polymerization reaction with a first catalyst to a polymerization reaction with a second catalyst that is incompatible with the first catalyst,
a) conducting a polymerization reaction using a first catalyst;
b) terminating the polymerization reaction with the first catalyst;
c) introducing a reversible inactivating agent;
d) removing said deactivating agent through nitrogen ventilation;
e) introducing hydrogen in an amount of 10 to 30 times the amount of hydrogen supplied to produce the olefin polymer melt index of 1 g / 10 min of said second catalyst, and establishing polymerization conditions using said second catalyst;
f) introducing a second catalyst; And
g) reducing the amount of hydrogen input to a hydrogen input amount to produce an olefin polymer melt index of 0.5 to 10 g / 10 min of the second catalyst, and continuing the second catalytic polymerization
&Lt; RTI ID = 0.0 &gt; 1, &lt; / RTI &gt; The method according to claim 1,
Wherein the first catalyst comprises a Ziegler Natta catalyst and the second catalyst comprises a metallocene catalyst. The method according to claim 1,
Wherein the reversible inactivating agent is carbon dioxide. The method according to claim 1,
The polymerization reaction using the first catalyst in the step a) is carried out under a condition of a reactor pressure of 15 to 25 kgf / cm 2, a reactor temperature of 70 to 90 ° C and an ethylene ratio of 20 to 50 mol% in the gas composition in the reactor . The method according to claim 1,
Wherein the supply of the first catalyst is stopped in the step b) and the polymerization reaction is stopped. 6. The method of claim 5,
Wherein the polymerization conditions are maintained for 1 to 10 hours after the supply of the first catalyst is stopped in the step b). The method according to claim 1,
Wherein the amount of the reversible deactivation agent in step c) is in the range of 5 to 20 molar equivalents relative to the total metal atoms present in the reactor. The method according to claim 1,
Further comprising, after step c) and after step d), maintaining the deactivating agent for 5 to 10 hours while flowing or stirring. The method according to claim 1,
Wherein no separate organometallic compound is added in step d), step e), step f), step g) and step h). 10. The method of claim 9,
Wherein the organometallic compound is a compound of the formula AlR _(3-n) X _n , wherein R is a branched or linear alkyl or cycloalkyl having 1 to 30 carbon atoms, or a hydride radical, X is halogen and n Lt; / RTI &gt; is 0, 1 or 2. The method according to claim 1,
Wherein the hydrogen input amount in the step e) is maintained for 0.5 to 2 times the internal product retention time. The method according to claim 1,
Wherein the polymerization conditions using the second catalyst in step e) are such that the reactor pressure is from 15 to 25 kgf / cm 2, the reactor temperature is from 70 to 90 ° C and the ethylene ratio in the reactor internal gas composition is from 20 to 80 mol%. The method according to claim 1,
Further comprising, after step g), h) determining whether to switch from a polymerization reaction using the first catalyst to a polymerization reaction using the second catalyst. 14. The method of claim 13,
The method according to any one of the above items (1) to (5), wherein the conversion of the product obtained in step (h) is carried out by measuring the gel content of the product obtained in step (a) and the product obtained in step (g). The method according to claim 1,
Wherein the polymerization reaction is a gas phase process.

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