Method for solution polymerization of ethylene-alpha-olefin copolymer using transition metal compound

Abstract

The method for solution polymerization of an ethylene-alpha-olefin copolymer according to the present invention can provide an ethylene-alpha-olefin copolymer having a low density of 0.90 g / cc or less and a wide molecular weight distribution of 2.0 or more and also can produce ethylene-alpha-olefin copolymers having significantly different molecular weights according to the amounts of hydrogen introduced.

Description

Solution polymerization method of ethylene-α-olefin copolymer using transition metal compounds

[0001] The present invention relates to a solution polymerization method for an ethylene-α-olefin copolymer.

[0002] Conventional catalysts used in the polymerization of olefin-based polymers include metallocene catalysts and Ziegler-Natta catalysts, and the two conventional catalysts have different characteristics in terms of molecular weight, molecular structure, density, and melt flow index of the olefin-based polymers produced.

[0003] The above Ziegler-Natta catalyst has non-uniform active sites due to the metal components dispersed on the solid surface being non-uniform, and therefore, the olefin polymer produced using the catalyst has a wide molecular weight distribution and is suitable for providing olefin polymers having various molecular structures. Therefore, since conventional olefin polymers used as materials for films, containers, cables, pipes, or fibers use polymer resins having a wide molecular weight distribution, a high melt flow index, and very low viscosity, the production of polyolefins using a Ziegler-Natta catalyst has been preferred.

[0004] However, since the above Ziegler-Natta catalyst has a uniform active site, it is difficult for a person skilled in the art to precisely control the viscosity, molecular weight distribution, molecular structure, and repeating unit content of comonomer, etc. that are targeted, and thus it is difficult to polymerize an olefin polymer having optimal properties according to the material used.

[0005] Metallocene catalysts are one of the catalysts used in ethylene polymerization, which are coordinated to a metal or a halogen compound on a metal by a ligand such as cyclopentadienyl, cycloheptadienyl, indenyl, or fluorenyl, and basically have a sandwich structure with each parent group. Since all active sites of a metallocene catalyst are uniform, when producing an olefin polymer using it, it has the advantage of being able to produce an olefin polymer with a narrow molecular weight distribution and a uniform distribution of comonomers.

[0006] For example, in Patent Document 1 (US Patent Publication No. US 5272236 A), when polymerizing an olefin-based polymer using a metallocene catalyst, the physical properties of the polymerized olefin-based polymer are controlled by controlling various polymerization conditions such as reaction temperature, monomer input amount, oxygen input amount, and stirring speed.

[0007] However, the conventional polymerization method of olefin-based polymers using metallocene catalysts has the problem that it cannot dramatically control the properties of the olefin-based polymers produced by simply controlling the polymerization conditions.

[0008] Therefore, there is a need for the development of a new metallocene catalyst and a polymer polymerization method using the same, which not only enables the production of polymers with a wide molecular weight distribution and low density through polymerization using a metallocene catalyst, but also enables the production of polymers with properties such as molecular weight more precisely controlled depending on the reaction conditions.

[0009] The purpose of the present invention is to provide a solution polymerization method for an ethylene-α-olefin copolymer capable of producing an ethylene-α-olefin copolymer having a low density and a broad molecular weight distribution.

[0010] Another object of the present invention relates to a solution polymerization method for an ethylene-α-olefin copolymer, and provides a solution polymerization method for an ethylene-α-olefin copolymer using a transition metal compound capable of producing distinct ethylene-α-olefin copolymers having a large difference in weight average molecular weight under the same catalyst mixture, the same olefin monomer, and the same reaction conditions.

[0011] The present invention provides a solution polymerization method for an ethylene-α-olefin copolymer using a catalyst composition comprising a transition metal compound of the following chemical formula 1 and a cocatalyst, wherein the density of the ethylene-α-olefin copolymer measured by ASTM D1505 is 0.90 g / cc or less and the molecular weight distribution is 2.0 or more.

[0012] [Chemical Formula 1]

[0013]

[0014] (In the above chemical formula 1, M is a metal of group 4 in the periodic table, R1 is a straight or branched C1-C7 alkyl, R2 and R3 are each independently hydrogen, straight or branched C1-C7 alkyl, C4-C 20 Cycloalkyl or C6-C 20 aryl, and n is an integer from 0 to 3.)

[0015] As one embodiment of the present invention, in the chemical formula 1, M is Zr (zirconium) or Ti (titanium), R1 is a straight or branched C1-C4 alkyl, R2 and R3 are each independently a straight or branched C1-C4 alkyl, and n may be 0 or 1.

[0016] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may satisfy the following equation 1.

[0017] [Formula 1]

[0018] 2 ≤ Mw1 / Mw0

[0019] (In the above equation 1, Mw1 is the weight average molecular weight of the ethylene-α-olefin copolymer manufactured when no hydrogen is added, and Mw0 is the weight average molecular weight of the ethylene-α-olefin copolymer manufactured when 20,000 ppm of hydrogen is added with respect to the total amount of the added input.)

[0020] As one embodiment of the present invention, the ethylene-α-olefin copolymer may have a weight average molecular weight of 10,000 to 200,000 g / mol.

[0021] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may have an internal pressure of 10 to 100 bar in the reactor.

[0022] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may have a polymerization reaction temperature of 30 to 200°C.

[0023] As one embodiment of the present invention, the cocatalyst may be at least one selected from the group consisting of N,N-diethylanilinium tetrakispentafluorophenylborate, N,N-2,4,6-pentamethylanilinium tetrakispentafluorophenylborate, and N,N-dimethylanilinium tetrakis3,5-bistrifluoromethylphenylborate.

[0024] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may use at least one solvent selected from the group consisting of n-hexane, n-heptane, n-butane, n-pentane, n-octane, and cyclohexane.

[0025] As one embodiment of the present invention, the ethylene-α-olefin copolymer may be a copolymer of ethylene and at least one α-olefin selected from the group consisting of 1-octene, 1-hexene, and 1-butene.

[0026] As one embodiment of the present invention, the ethylene-α-olefin copolymer may have 50 to 99 mol% of ethylene repeating units based on the total repeating units.

[0027] As one embodiment of the present invention, the ethylene-α-olefin copolymer may have a melt flow index of 0.1 to 1,500 g / 10 min at a load of 2.16 kg as measured by ASTM D1238.

[0028] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may include a) a step of preparing an α-olefin composition by mixing an α-olefin in a solvent, and b) a step of introducing a catalyst composition into the α-olefin composition and introducing ethylene into a reactor to polymerize the ethylene-α-olefin copolymer.

[0029] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may additionally add hydrogen in step b).

[0030] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may further include at least one aluminum scavenger selected from the group consisting of trimethylaluminum, triethylaluminum, tripropylaluminum, triisobutylaluminum, and trihexylaluminum.

[0031] The solution polymerization method of the ethylene-α-olefin copolymer of the present invention can easily produce products having various molecular weights in a wide range depending on the amount of hydrogen input without having to adjust reaction conditions such as separate combinations of equivalents and reaction temperatures according to molecular weight, thereby producing ethylene-α-olefin copolymers that can be used for various purposes with one reactor.

[0032] The solution polymerization method of the ethylene-α-olefin copolymer of the present invention can produce an ethylene-α-olefin copolymer having a low density and a wide molecular weight distribution, so that the produced ethylene-α-olefin copolymer can be usefully used in materials requiring excellent processability, such as films, wraps, or bottles.

[0033] The present invention will be described in more detail below. However, the following specific examples or examples are merely references for explaining the present invention in detail, and the present invention is not limited thereto, and may be implemented in various forms.

[0034] Additionally, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing specific embodiments only and is not intended to be limiting.

[0035] Additionally, the singular forms used in the specification and the appended claims are intended to include the plural forms as well, unless the context clearly dictates otherwise.

[0036] Additionally, when a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0037] In addition, the terms "about", "substantially", etc. used in this specification are used in the sense of or close to the numerical value when manufacturing and material tolerances inherent to the meanings mentioned are presented, and are used to prevent unscrupulous infringers from unfairly exploiting the invention contents in which exact or absolute numerical values ​​are mentioned to aid understanding of the invention.

[0038] One embodiment of the present invention may provide a solution polymerization method for producing an ethylene-α-olefin copolymer using a catalyst composition comprising a transition metal compound of the following chemical formula 1 and a cocatalyst.

[0039] [Chemical Formula 1]

[0040]

[0041] (In the above chemical formula 1, M is a metal of group 4 in the periodic table, R1 is a straight or branched C1-C7 alkyl, R2 and R3 are each independently hydrogen, straight or branched C1-C7 alkyl, C4-C 20 Cycloalkyl or C6-C 20 aryl, and n is an integer from 0 to 3.)

[0042] At this time, the ethylene-α-olefin copolymer manufactured by the solution polymerization method of the ethylene-α-olefin copolymer may have a density of 0.900 g / cc or less as measured by ASTM D1505, and a molecular weight distribution of 2.0 or more.

[0043] As one embodiment of the present invention, the ethylene-α-olefin copolymer may have a density of 0.900 g / cc or less, preferably 0.850 to 0.900 / cc, and more preferably 0.860 to 0.880 g / cc, 0.860 to 0.879 g / cc, or 0.860 to 0.875 g / cc.

[0044] Since the above ethylene-α-olefin copolymer has a low density in the above range, it can have high processability and can be particularly usefully used as a material for wraps, films, bottles, etc.

[0045] As one embodiment of the present invention, the ethylene-α-olefin copolymer may have a molecular weight distribution of 2.0 or more, 2.5 or more, 3.0 or more, 4.0 or more, or 5.0 or less and values ​​thereof.

[0046] The ethylene-α-olefin copolymer within the above range may have both brittleness and elasticity, and thus may be preferred because it is easy to mold by stretch molding or blow molding, and products manufactured by including the copolymer may not be easily broken.

[0047] The molecular weight distribution of the above ethylene-α-olefin copolymer can be further broadened depending on the process scale of the solution polymerization method of the ethylene-α-olefin copolymer. For example, in the case of polymerization on a laboratory (rab) scale as in the example described below, the molecular weight distribution can satisfy 2.5 or more.

[0048] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may satisfy the following equation 1.

[0049] [Formula 1]

[0050] 2 ≤ Mw1 / Mw0

[0051] (In the above equation 1, Mw1 is the weight average molecular weight of the ethylene-α-olefin copolymer manufactured when no hydrogen is added, and Mw0 is the weight average molecular weight of the ethylene-α-olefin copolymer manufactured by adding 20,000 ppm of hydrogen based on the total amount of the added input.)

[0052] In the above formula 1, the input may mean all compounds input into the reactor, such as a solvent, monomer, and catalyst composition.

[0053] As another embodiment, the above ethylene-α-olefin copolymer solution polymerization method can satisfy Mw1 / Mw0 of 2.5 or more, preferably 3.0 or more, 3.5 or more, and more preferably 4.0 or more in the above formula 1, and although the upper limit is not limited, it can satisfy 7.0 or less, 6.0 or less, or 5.0 or less.

[0054] The solution polymerization method of the above ethylene-α-olefin copolymer satisfies the above-described range of Mw1 / Mw0, and thus enables the production of ethylene-α-olefin copolymers as individual grades having various molecular weights in a wide molecular weight range, so that the produced ethylene-α-olefin copolymer can be used as a variety of materials from high fluidity to low fluidity.

[0055] As another embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer can control the molecular weight of the ethylene-α-olefin copolymer by controlling the hydrogen input amount in the range of 100 ppm to 100,000 ppm, preferably 1,000 to 50,000 ppm, even if the hydrogen input amount is not defined in the above formula 1.

[0056] As another embodiment according to Example 1 of the present invention, the ethylene-α-olefin copolymer has a weight average molecular weight of 146,100 g / mol when no hydrogen is added during polymerization, but when polymerized by adding 10,000 ppm, 20,000 ppm, and 30,000 ppm of hydrogen, the molecular weights are 56,049 g / mol, 34,059 g / mol, and 26,852 g / mol, respectively, so that polymers with a molecular weight difference of more than 4 times can be produced in the same polymerization system. In other words, product diversity can be easily achieved without changing the catalyst.

[0057] Therefore, the solution polymerization method of the above ethylene-α-olefin copolymer can produce an ethylene-α-olefin copolymer having a low density in the range described above and a wide molecular weight distribution by using a catalyst composition including the transition metal compound of the above chemical formula 1, and thus can be usefully used for materials requiring excellent processability such as films, wraps, or bottles.

[0058] In addition, the solution polymerization method of the ethylene-α-olefin copolymer can provide a low molecular weight polyolefin having a weight average molecular weight of an ethylene-α-olefin copolymer obtained by adding 20,000 ppm of hydrogen to ethylene during solution polymerization using a catalyst composition including a transition metal compound of the above chemical formula 1, which is 1 / 2, 1 / 3, or 1 / 4 or less of the molecular weight of an ethylene-α-olefin copolymer polymerized using the same catalyst composition without adding hydrogen.

[0059] That is, the solution polymerization method of the above ethylene-α-olefin copolymer can provide various grades of ethylene-α-olefin copolymers having different molecular weights for each polymerization lot simply by changing the amount of hydrogen input in the same metal transition compound, the same monomer combination, and the same reactor, and thus, each ethylene-α-olefin copolymer having a large difference in molecular weight can be manufactured in a reactor of a small volume, which may be preferred.

[0060] In one embodiment of the present invention, the ethylene-α-olefin copolymer may have a weight average molecular weight of 10,000 to 200,000 g / mol, and in another embodiment, may have a weight average molecular weight of 10,000 to 150,000 g / mol.

[0061] As described above, the above ethylene-α-olefin copolymer can control the weight average molecular weight depending on the amount of hydrogen input, and thus can provide an ethylene-α-olefin copolymer having a wide range of molecular weights, and thus can be applied and used in various ways to materials requiring high molecular weight and materials requiring low molecular weight.

[0062] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may have a melt flow index of 0.1 to 1,500 g / 10 min at a load of 2.16 kg as measured by ASTM D1238, preferably 0.5 to 1,500 g / 10 min, more preferably 1.0 to 1,500 g / 10 min, even though the same catalyst composition is adopted.

[0063] That is, the solution polymerization method of the above ethylene-α-olefin copolymer has a very wide melt flow index, and thus can produce resins requiring various processability and mechanical strength.

[0064] As one embodiment of the present invention, the ethylene-α-olefin copolymer may be a copolymerization comprising ethylene and at least one α-olefin selected from the group consisting of 1-octene, 1-hexene, and 1-butene, and as another embodiment, the α-olefin may be 1-octene, 1-hexene, or a mixed monomer thereof or 1-octene, but is not necessarily limited thereto.

[0065] As one embodiment of the present invention, as one embodiment of the present invention, the ethylene-α-olefin copolymer may have 50 to 99 mol% of ethylene repeating units based on the total repeating units, and in another embodiment, may have 60 to 99 mol% or 70 to 99 mol%.

[0066] An ethylene-α-olefin copolymer containing ethylene repeating units in the above range can have a density in the range described above, and can also have excellent mechanical strength and high heat-sealability, so that it can be usefully used as a heat-sealable film, but is not necessarily limited thereto.

[0067] Accordingly, as an embodiment of the present invention, an ethylene-α-olefin copolymer having an ethylene repeating unit of 50 to 99 mol%, a density measured by ASTM D1505 of 0.850 to 0.900 g / cc, a molecular weight distribution of 2.0 to 5.0, and a weight average molecular weight of 10,000 to 200,000 g / mol can be provided.

[0068] Since the above ethylene-α-olefin copolymer satisfies the above properties simultaneously, it can be usefully used as a main resin component or various resin components such as a wax component in materials such as films, wraps, or bottles.

[0069] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer can produce ethylene-α-olefin copolymers having various molecular weights and the above-described properties using a catalyst composition including a transition metal compound of the following chemical formula 1 and a cocatalyst.

[0070] [Chemical Formula 1]

[0071]

[0072] (In the above chemical formula 1, M is a metal of group 4 in the periodic table, R1 is a straight or branched C1-C7 alkyl, R2 and R3 are each independently hydrogen, straight or branched C1-C7 alkyl, C4-C 20 Cycloalkyl or C6-C 20 aryl, and n is an integer from 0 to 3.)

[0073] The transition metal compound represented by the above chemical formula 1 has particularly excellent reactivity with hydrogen, and thus, the solution polymerization method of an ethylene-α-olefin copolymer using the compound can easily control the weight average molecular weight of the ethylene-α-olefin copolymer produced simply by controlling the amount of hydrogen introduced.

[0074] That is, the solution polymerization method of ethylene-α-olefin copolymer according to one embodiment of the present invention

[0075] Compared to the molecular weight diversity of ethylene-α-olefin copolymers produced using conventional transition metal compounds, a wider range of molecular weights can be controlled. Therefore, the solution polymerization method for the ethylene-α-olefin copolymer not only enables the production of copolymers for a wider range of applications using the same catalyst composition, but also, in the present invention, provides ethylene-α-olefin copolymers having the desired density and molecular weight distribution.

[0076] As another embodiment of the present invention, the transition metal compound may have a structure in which, in the chemical formula 1 described above, M is Zr (zirconium) or Ti (titanium), R1 is a straight or branched C1-C4 alkyl, R2 and R3 are each independently a straight or branched C1-C4 alkyl, and n is an integer of 0 or 1, and preferably, in the chemical formula 1, M is Zr, R1 is ethylene or n-butylene, R2 and R3 are each independently methylene or ethylene, and n is 0 or 1.

[0077] The solution polymerization method of an ethylene-α-olefin copolymer using a transition metal compound of the chemical formula 1 described above can be preferred because it can produce an ethylene-α-olefin copolymer having a wider range of weight average molecular weights by controlling the hydrogen content, and can also produce an ethylene-α-olefin copolymer satisfying the density and molecular weight distribution ranges described above.

[0078] As one embodiment of the present invention, the activity of the transition metal compound may be 400 kg(mPo) / g·hr(cat) or more, 500 kg(mPo) / g·hr(cat) or more, 550 kg(mPo) / g·hr(cat) or more, 600 kg(mPo) / g·hr(cat) or more, and the upper limit is not limited, but may be 800 kg(mPo) / g·hr(cat) or less or 700 kg(mPo) / g·hr(cat) or less.

[0079] The activity of the above transition metal compound may be the content (kg) of the ethylene-α-olefin copolymer (mPo) produced per hour relative to the content (g) of the transition metal compound (cat) included in the solution polymerization method of the ethylene-α-olefin copolymer.

[0080] Since the above transition metal compound has an activity in the above range, solution polymerization of an ethylene-α-olefin copolymer using the compound can have excellent polymerization reactivity and may be preferred.

[0081] Hereinafter, the solution polymerization method of the ethylene-α-olefin copolymer of the present invention will be described in more detail.

[0082] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may include a) a step of preparing an α-olefin composition by mixing an α-olefin in a solvent, and b) a step of introducing a catalyst composition into the α-olefin composition and introducing ethylene into a reactor to copolymerize the ethylene-α-olefin copolymer.

[0083] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may additionally add hydrogen in step b).

[0084] The above solution polymerization method of ethylene-α-olefin copolymer can control the weight average molecular weight of the ethylene-α-olefin copolymer by introducing hydrogen in step b), and can also manufacture various types of ethylene-α-olefin copolymers having a wide range of weight average molecular weights by adjusting the amount of hydrogen introduced during step b).

[0085] As another embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may be performed by sequentially adding hydrogen, a transition metal compound, ethylene, and a cocatalyst to an α-olefin composition.

[0086] As another embodiment, the solution polymerization method of the ethylene-α-olefin copolymer may be carried out by contacting the transition metal compound, the cocatalyst, and ethylene in the presence of a solvent. At this time, the transition metal compound and the cocatalyst components may be separately introduced into the reactor, or each component may be mixed in advance and introduced into the reactor. However, the mixing conditions, such as the order of introduction, temperature, or concentration listed above, are not necessarily limited as long as the physical properties of the ethylene-α-olefin copolymer are not impaired.

[0087] As one embodiment of the present invention, the solvent may be at least one selected from the group consisting of n-hexane, n-heptane, n-butane, n-pentane, n-octane, and cyclohexane.

[0088] As another embodiment, the solvent may be n-hexane or cyclohexane, and n-hexane may be used alone in view of its excellent solubility in α-olefins, but this is not necessarily limited as long as it allows α-olefin dissolution and does not impair the properties of the ethylene-α-olefin copolymer produced.

[0089] As one embodiment of the present invention, the α-olefin may be at least one selected from the group consisting of 1-octene, 1-hexene, and 1-butene, and since this is the same as described in the comonomer of the ethylene-α-olefin copolymer, a detailed description thereof will be omitted.

[0090] In one embodiment of the present invention, the ethylene-α-olefin copolymer may have 50 to 99 mol% of ethylene repeating units based on the total repeating units, and in another embodiment, may have 60 to 99 mol% or 70 to 99 mol%, but is not necessarily limited thereto.

[0091] An ethylene-α-olefin copolymer manufactured by including an α-olefin in the above range can have excellent mechanical strength and high heat-sealability, and thus can be advantageously used as a heat-sealable film.

[0092] In one embodiment of the present invention, the α-olefin composition may contain 0.1 to 1 M of α-olefin, and in another embodiment, it may contain 0.5 to 1 M, but this is not necessarily limited thereto.

[0093] As one embodiment of the present invention, the catalyst composition may be a mixture of the above-described metal transition compound and a cocatalyst.

[0094] As one embodiment of the present invention, the cocatalyst may be any one or more selected from the group consisting of N,N-diethylanilinium tetrakispentafluorophenylborate, N,N-2,4,6-pentamethylanilinium tetrakispentafluorophenylborate, and N,N-dimethylanilinium tetrakis3,5-bistrifluoromethylphenylborate, etc., as long as it is recognizable by a person skilled in the art, but is not particularly limited thereto.

[0095] As another embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may use N-diethylanilinium tetrakispentafluorophenylborate or N,N-2,4,6-pentamethylanilinium tetrakispentafluorophenylborate as a cocatalyst, or use N-diethylanilinium tetrakispentafluorophenylborate alone, which may facilitate control of the molecular weight of the ethylene-α-olefin copolymer produced, but is not necessarily limited thereto.

[0096] As one embodiment of the present invention, the catalyst composition may be a mixture of a transition metal compound and a cocatalyst at a molar ratio of 1:5 or more, for example, 1:5 to 1:10, and in another embodiment, 1:5 to 1:8 or 1:5 to 1:7.

[0097] A catalyst composition satisfying the above molar ratio does not inhibit the properties of a transition metal compound, increases the activity of the transition metal compound, and thus a solution polymerization method of an ethylene-α-olefin copolymer including the catalyst composition can have excellent polymerization reactivity, but is not necessarily limited thereto.

[0098] The solution polymerization method of the above ethylene-α-olefin copolymer has excellent polymerizability of the transition metal compound represented by the above chemical formula 1 and excellent reactivity with hydrogen, so that an ethylene-α-olefin copolymer having a large difference in weight average molecular weight as shown in the following chemical formula 1 can be produced.

[0099] In one embodiment of the present invention, the solution polymerization method of an ethylene-α-olefin copolymer may have an internal pressure of 10 to 100 bar in the reactor, and in another embodiment, it may be 20 to 80 bar or 20 to 50 bar.

[0100] The pressure inside the reactor of the solution polymerization method of the above ethylene-α-olefin copolymer may be preferred in terms of the ethylene-α-olefin copolymer being manufactured having the target weight average molecular weight, content of ethylene repeating units, and molecular weight distribution, but is not particularly limited as long as it is recognizable by a person skilled in the art.

[0101] As another embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may be one in which ethylene (gas) is introduced at a pressure of 10 to 30 bar within the reactor, or at a pressure of 15 to 25 bar, but this may vary depending on the volume of the reactor, and is therefore not necessarily limited thereto.

[0102] An ethylene-α-olefin copolymer manufactured by injecting ethylene at a pressure within the above range may contain the target ethylene repeating unit and thus may have excellent physical properties and may be preferred.

[0103] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may further include introducing an inert gas, and the gas may be introduced at an internal pressure of 10 to 40 bar, 10 to 30 bar, or 20 to 30 bar in the reactor.

[0104] The above inert gas may be introduced after ethylene is introduced into the reactor, and this may be preferred because the pressure inside the reactor, which is lowered due to consumption of ethylene in the step of copolymerizing the b) ethylene-α-olefin copolymer, can be maintained at 10 to 100 bar as described above.

[0105] The above inert gas is not particularly limited, but may be, as a non-limiting example, helium, neon, or argon, and it may be preferred to use argon in terms of providing a safer solution polymerization method of ethylene-α-olefin copolymer.

[0106] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may further include an aluminum scavenger, and it may be preferred to introduce the scavenger before introducing ethylene, a transition metal compound, and a cocatalyst.

[0107] The solution polymerization method of an ethylene-α-olefin copolymer further including the above scavenger may be preferred because it can produce a high-purity ethylene-α-olefin copolymer by removing oxygen, moisture, and impurities contained in the α-olefin composition.

[0108] In one embodiment of the present invention, the aluminum scavenger may be at least one selected from the group consisting of trimethylaluminum, triethylaluminum, tripropylaluminum, triisobutylaluminum, and trihexylaluminum, and in another embodiment, using triisobutylaluminum alone can produce a higher purity ethylene-α-olefin copolymer, but this is not necessarily limited thereto.

[0109] As one embodiment of the present invention, the aluminum scavenger may be added in an amount of 0.5 to 2 μmol or 0.5 to 0.5 to 1.5 μmol per 1 liter of the α-olefin composition, but this is not necessarily limited thereto.

[0110] As one embodiment of the present invention, the solution polymerization method of the ethylene-α-olefin copolymer may have a polymerization reaction temperature of 30 to 200°C, and as another embodiment, it may be 50 to 150°C, or 60 to 100°C.

[0111] The polymerization temperature within the above range can be excellent in the polymerization processability of the solution polymerization method of the ethylene-α-olefin copolymer due to the high activity of the transition metal compound, and can reduce the volume of the process and process equipment for recycling the unreacted monomer due to the low content of unreacted ethylene and α-olefin. However, this is not necessarily limited as long as it does not impair the physical properties of the ethylene-α-olefin copolymer produced.

[0112] The present invention will be described in more detail based on the following examples and comparative examples. However, the following examples and comparative examples are merely illustrative examples for further explaining the present invention, and the present invention is not limited by these examples and comparative examples.

[0113] [measurement method]

[0114] 1. GPC (gel permeation chromatography) measurement

[0115] The measurement solution of ethylene-α-olefin copolymer dissolved in trichlorobenzene was measured using GPC (Polymer Char, GPC-6), and the weight average molecular weight and molecular weight distribution (PDI) were obtained by controlling the conditions of 160 ℃ and flow rate of 1.0 ml / min using a column (Agilient, PL gel Olexis column).

[0116] 2. Measurement of changes in weight-average molecular weight according to hydrogen input amount

[0117] Under the same reaction conditions such as transition metal compound, cocatalyst, and temperature, the weight average molecular weight (Mw1) of the ethylene-1-octene copolymer manufactured without adding hydrogen gas was divided by the weight average molecular weight (Mw0) of the ethylene-1-octene copolymer manufactured by adding 20,000 ppm of hydrogen gas, and the value calculated was expressed as the change rate of the weight average molecular weight, and the weight average molecular weight was measured using the same method as the GPC measurement method mentioned above.

[0118] 3. Density measurement

[0119] Measured according to ASTM D1505.

[0120] 4. Melt Flow Index (MI) Measurement

[0121] It was measured according to ASTM D1238, and the melt flow index (g / 10 min) was measured under the condition of a load of 2.16 kg after melting at 190 ℃.

[0122] [Manufacturing Example 1]

[0123]

[0124] 2,7-Di-t-butylfluorene (2.00 g, 7.2 mmol) was dissolved in 30 mL of diethyl ether, and 4.7 mL of a hexane solution of n-Butyllithium (1.6 M concentration) was slowly added at room temperature, and the mixture was stirred at the same temperature for 12 hours. Afterwards, 1.65 g (7.2 mmol) of diphenylfulvene was slowly added to the stirred solution, and stirring was continued again at 80 °C for 12 hours. After stirring, the solution was filtered, and the filtered solution was dried in an oven to obtain 2.67 g (5.2 mmol) of compound A in a yield of 73%.

[0125]

[0126] Afterwards, 1.0 g (1.97 mmol) of the obtained compound A was dissolved in 20 ml of ether, and 2.6 ml of a hexane solution of 1.6 M n-Butyllithium was slowly added at -30 °C. Afterwards, the temperature was raised to room temperature and stirred for 12 hours, and the temperature was lowered again to -30 °C, and 458 mg (1.97 mmol) of ZrCl4 was added. Afterwards, the temperature was raised to room temperature and stirred for 12 hours to react, and after completion of the reaction, the solvent was dried, and the dried reactant was immersed in toluene to wash away residual impurities, and then dried in an oven to remove toluene, obtaining 224 g of compound B with a yield of 81%. The manufactured compound B was measured by NMR [1H-NMR (CDCl3, 300 MHz)], and the measured values ​​were 8.07 (d, 2H), 7.99 (d, 2H), 7.92 (d, 2H), 7.63 (dd, 2H), 7.48 (dt, 2H), 7.39 (dt, 2H), 7.32-7.28 (m, 2H), 6.38-6.36 (m, 4H), 5.71 (t, 2H), 1.07 (s, 18H), confirming that compound B was manufactured.

[0127]

[0128] Finally, 0.5 g (0.75 mmol) of the above-obtained compound B was dissolved in 10 ml of toluene, and then, while cooled to -30°C, 0.75 ml of a 3.0 M ether solution of methylmagnesium bromide was slowly added. After this, the temperature was raised to room temperature and the mixture was stirred for 12 hours to react. After completion of the reaction, the solvent was dried and the mixture was immersed in hexane to wash away impurities, and then dried in an oven to obtain 375 mg of Preparation Example 1 with a yield of 75%. As a result of NMR measurement of the manufactured Manufacturing Example 1 [1H-NMR (CDCl3, 300 MHz)], 8.12 (d, 2H), 7.97 (d, 2H), 7.87 (d, 2H), 7.48 (dd, 2H), 7.39 (dt, 2H), 7.31-7.20 (m, 4H), 6.31 (t, 2H), 6.23 (d, 2H), 5.50 (t, 2H), 1.06 (s, 18H), -1.68 (s, 6H) were measured, confirming that Manufacturing Example 1 was manufactured.

[0129] [Manufacturing Example 2]

[0130] To dissolve 4 ml of a 2.4 M THF solution of sodium cyclopentadienylide was added slowly at -30 °C. The mixture was stirred for 12 hours and allowed to warm to room temperature. The solution was filtered to remove salts, and 6.6 ml of a 1.6 M hexane solution of n-butyllithium was slowly added at -30 °C. The mixture was allowed to warm to room temperature and stirred for 12 hours. To the stirred solution, 1.75 g (9.6 mmol) of benzophenone was slowly added at -30 °C, the mixture was allowed to warm to room temperature and stirred for 12 hours, and a 10 wt% concentrated HCl aqueous solution was added to extract the pentane reactant. The extracted reactant was then subjected to column chromatography (Polymer Char, GPC-6) to obtain 1.65 g of 2-butyl-6,6-diphenylpentafulvene with a yield of 60%.

[0131]

[0132] 1.00 g (3.6 mmol) of 2,7-Di-t-butylfluorene was dissolved in 15 ml of diethyl ether, and 2.4 ml of a 1.6 M hexane solution of n-Butyllithium was slowly added at room temperature, and the mixture was stirred at the same temperature for 12 hours. 1.03 g (3.6 mmol) of the obtained 2-butyl-6,6-diphenylpentafulvene was slowly added to the stirred solution at room temperature, and the mixture was stirred at the same temperature for 12 hours. After stirring, the solution was filtered and dried in an oven to obtain 854 mg (1.5 mmol) of compound C in a yield of 42%.

[0133]

[0134] Afterwards, 0.5 g (0.89 mmol) of the obtained compound C was dissolved in 10 ml of ether, and 1.2 ml of a hexane solution of n-Butyllithium having a concentration of 1.6 M was slowly added at -30 °C. Afterwards, the temperature was raised to room temperature and stirred for 12 hours, and the temperature was lowered again to -30 °C, and 405 mg (0.89 mmol) of ZrCl4 was added. Afterwards, the temperature was raised to room temperature and stirred for 12 hours to react, and after completion of the reaction, the solvent was dried, and the dried reactant was immersed in toluene to wash away residual impurities, and then dried in an oven to remove toluene, obtaining 224 g of compound D with a yield of 35%. The manufactured compound D was measured by NMR [1H-NMR (CDCl3, 300 MHz)], and the measured values ​​were 8.06-7.85 (m, 6H), 7.59-7.22 (m, 8H), 6.27 (d, 2H), 6.02 (m, 1H), 5.57 (m, 1H), 5.31 (m, 1H), 2.37 (m, 2H), 1.53-0.85 (m, 9H), 1.02 (s, 18H), confirming that compound D was manufactured.

[0135]

[0136] Finally, 0.224 g (0.31 mmol) of the compound D obtained above was dissolved in 5 ml of toluene, and then, while cooled to -30°C, 0.75 ml of 3.0 M ether solution of methylmagnesium bromide was slowly added. After that, the temperature was raised to room temperature and stirred for 12 hours to react. After completion of the reaction, the solvent was dried and impurities were washed away by immersion in hexane, and then dried in an oven to obtain 138 mg of Preparation Example 2 with a yield of 65%. As a result of NMR measurement of the manufactured Manufacturing Example 2 [1H-NMR (CDCl3, 300 MHz)], 8.10-7.80 (m, 6H), 7.44-7.14 (m, 8H), 6.16 (d, 2H), 5.98 (m, 1H), 5.36 (m, 1H), 5.16 (m, 1H), 2.31 (m, 2H), 1.58-0.81 (m, 9H), 1.02 (s, 18H), -1.77 (d, 6H) were measured, confirming that Manufacturing Example 2 was manufactured.

[0137] [Comparative Manufacturing Example 1]

[0138] Comparative Manufacturing Example 1 was obtained by reacting in the same manner as in Manufacturing Example 1 except that 9H-fluorene was used instead of 2,7-Di-t-butylfluorene.

[0139]

[0140] [Comparative Manufacturing Example 2]

[0141] Comparative Manufacturing Example 2 was obtained by the same reaction as in Manufacturing Example 2 except that 9H-fluorene was used instead of 2,7-Di-t-butylfluorene and n-butyl-substituted diphenylpentafulvene was used instead of diphenylpentafulvene.

[0142]

[0143] [Comparative Manufacturing Example 3]

[0144] By reacting in the same manner as described in U.S. Patent Publication No. US 5272236 A (November 29, 1993), a transition metal compound represented by the following chemical formula 2 was obtained.

[0145] [Chemical Formula 2]

[0146]

[0147] [Examples 1 to 6 and Comparative Examples 1 to 6]

[0148] A 2-liter autoclave reactor was used to remove moisture and impurities inside the reactor using a vacuum pump and maintain a low pressure of 0.3 torr or less, and the temperature of the reactor was raised to 60°C while purging the reactor using argon (Ar) gas for more than 30 minutes.

[0149] A hexane solution containing 1-octene dissolved in a concentration of 0.8 M was introduced into a heated reactor, and 2 ml of triisobutyl aluminum (TiBAL) with a concentration of 1 M was introduced as a scavenger. Hydrogen was introduced in an amount shown in Table 1 below based on the total amount of the input into the reactor. Thereafter, the reactor was stirred at a speed of 500 rpm and heated to 80°C. Upon reaching 80°C, 2 μmol of the transition metal compounds shown in Table 1 below and ethylene were introduced into the reactor at 20 bar. Argon was continuously introduced into the reactor to maintain a pressure of 25 bar after the introduction of the catalyst and ethylene, and 12 μmol of dimethylanilinium tetrakis(pentafluorophenyl)borate was additionally introduced into the pressurized reactor as a cocatalyst.

[0150] The temperature of the reactor, in which the cocatalyst and argon gas were maintained at a constant pressure, was raised from 80°C to 120°C to carry out a polymerization reaction, and 5 minutes after the polymerization reaction, the argon injection was stopped to terminate the reaction.

[0151] The molten polymer inside the reactor was transferred to a separator through the reactor outlet, unreacted ethylene and 1-octene were separated from the hexane solvent, and the polymer was dried in a vacuum oven at 80°C for 12 hours to obtain an ethylene-1-octene copolymer.

[0152] The obtained ethylene-1-octene copolymer was measured using the above measurement method and the results are shown in Table 1 below.

[0153] Catalyst type Activity (kg mPO / g cat.h) Hydrogen (ppm) Weight average molecular weight (g / mol) Molecular weight change (Mw1 / Mw0) PDI Density (g / cc) MI (g / 10min) Example 1 Manufacturing Example 1 5510146, 1004.29 2.9 0.87 4 1.34 Example 2 55610, 00056, 049 2.8 0.87 4 Not measurable Example 3 56120, 00034, 059 2.7 0.875 Not measurable Example 4 52430, 00026, 85 22.7 0.874 Not measurable Example 5 Manufacturing Example 2 4820121, 265 2.94 3.30.87 23.91 Example 644520,00041,2113.40.872UnmeasurableComparative Example 1Comparative Manufacturing Example 14420124,5801.611.40.8763.24Comparative Example 238420,00077,4221.50.87712.0Comparative Example 3Comparative Manufacturing Example 24030100,2351.331.70.8802.08Comparative Example 441520,00075,3341.50.8799.56Comparative Example 5Comparative Manufacturing Example 460073,4641.451.50.8847.48Comparative Example 634520,00050,6941.80.88515.6

[0154] In the above Table 1, in the case of Examples 1 to 6, it can be seen that the difference in weight average molecular weight between the ethylene-1-octene copolymer manufactured without adding hydrogen and the ethylene-α-olefin copolymer manufactured by increasing the amount of hydrogen added is large, about 2 to 4 times.

[0155] Taking Example 1 as an example, when only the amount of hydrogen input was controlled under the same catalyst mixture, the same monomer, and the same temperature conditions, in the same reactor, in Example 2, where 10,000 ppm of hydrogen was input, the weight molecular weight decreased by more than 2 times to 56,049 g / mol. In addition, in Example 3, where 20,000 ppm of hydrogen was input, the weight average molecular weight decreased by more than 4 times, and in Example 3, where 30,000 ppm of hydrogen was input, the molecular weight decrease rate decreased by more than 5.3 times, so it can be seen that the weight average molecular weight decrease rate of the manufactured ethylene-α-olefin copolymer according to the amount of hydrogen input varies very greatly.

[0156] In contrast, in the case of Comparative Examples 1 to 6, the reduction rate of the molecular weight of ethylene-1-octene produced according to the amount of hydrogen input is very small, less than 2 times, so the range of change is not large, and it can be seen that it is impossible to produce various polymers having various molecular weights in the same reaction system.

[0157] In addition, it was confirmed that the ethylene-1-octene copolymers manufactured in Examples 1 to 4 had a density of 0.9 g / cc or less, preferably a very low density of 0.880 g / cc or 0.879 g / cc or less, more preferably 0.875 g / cc or less, and a molecular weight distribution of 2.0 or more, 2.5 or more, 2.7 or more, 2.8 or more, 2.9 or more, preferably 3.0 or more, more preferably 3.3 or 3.4, and a wide PDI.

[0158] In contrast, the ethylene-1-octene copolymers manufactured in Comparative Examples 1 to 6 had a density of 0.875 or higher, which was higher than that of Examples 1 to 6, and it was confirmed that the manufactured PDI was narrower than that of Examples 1 to 6.

[0159] Therefore, the solution polymerization method of an ethylene-α-olefin copolymer using a transition metal compound according to the present invention can not only provide an ethylene-α-olefin copolymer having a low density and a wide molecular weight distribution, but also easily produce an ethylene-α-olefin copolymer having a very wide range of weight average molecular weights simply by controlling the amount of hydrogen input.

[0160] That is, the solution polymerization method of the above ethylene-α-olefin copolymer is sensitive to the concentration of hydrogen and accordingly, the difference in molecular weight according to the hydrogen concentration can be controlled very greatly, so that ethylene-α-olefin copolymers having various molecular weights can be provided, each having a difference in molecular weight of 2 times or more or 4 times or more under the same catalyst mixture and cocatalyst, the same monomer, and the same reaction temperature conditions.

[0161] As described above, the present invention has been described through specific matters and limited examples, but these are provided only to help a more general understanding of the present invention, and the present invention is not limited to the above examples, and those skilled in the art to which the present invention pertains can make various modifications and variations based on this description.

[0162] Therefore, the idea of ​​the present invention should not be limited to the described embodiments, and all things that are equivalent or equivalent to the following claims as well as the claims are considered to fall within the scope of the idea of ​​the present invention.

Claims

1. A solution polymerization method of an ethylene-α-olefin copolymer using a catalyst composition comprising a transition metal compound of the following chemical formula 1 and a cocatalyst, The above ethylene-α-olefin copolymer is a solution polymerization method of an ethylene-α-olefin copolymer having a density of 0.90 g / cc or less and a molecular weight distribution of 2.0 or more as measured by ASTM D1505. [Chemical Formula 1] In the above chemical formula 1, M is a metal in group 4 of the periodic table, R 1 Silver straight or branched chain C 1 -C 7 It is alkyl, R 2 and R 3 are independently hydrogen, straight-chain or branched-chain C 1 -C 7 Alkyl, C 4 -C 20 Cycloalkyl or C 6 -C 20 It's Aryl, n is an integer from 0 to 3.

2. In paragraph 1, In the above chemical formula 1, M is Zr or Ti, R 1 Silver straight or branched chain C 1 -C 4 It is alkyl, R 2 and R 3 are linear or branched chain C independently of each other. 1 -C 4 It is alkyl, Solution polymerization method of ethylene-α-olefin copolymer where n is 0 or 1.

3. In paragraph 1, The solution polymerization method of the above ethylene-α-olefin copolymer is a solution polymerization method of an ethylene-α-olefin copolymer satisfying the following equation 1. [Formula 1] 2 ≤ Mw 1 / Mw 0 In the above equation 1, Mw 1 is the weight average molecular weight of the ethylene-α-olefin copolymer produced when no hydrogen is added, Mw 0 is the weight average molecular weight of the ethylene-α-olefin copolymer produced when hydrogen is added at 20,000 ppm with respect to the total amount of input materials.

4. In paragraph 1, The above ethylene-α-olefin copolymer is a solution polymerization method of an ethylene-α-olefin copolymer having a weight average molecular weight of 10,000 to 200,000 g / mol.

5. In paragraph 1, The above solution polymerization method for ethylene-α-olefin copolymer is a solution polymerization method for ethylene-α-olefin copolymer at a pressure inside the reactor of 10 to 100 bar.

6. In paragraph 1, The solution polymerization method of the above ethylene-α-olefin copolymer is a solution polymerization method of the ethylene-α-olefin copolymer having a polymerization reaction temperature of 30 to 200°C.

7. In paragraph 1, A solution polymerization method for an ethylene-α-olefin copolymer, wherein the cocatalyst is at least one selected from the group consisting of N,N-diethylanilinium tetrakispentafluorophenylborate, N,N-2,4,6-pentamethylanilinium tetrakispentafluorophenylborate, and N,N-dimethylanilinium tetrakis3,5-bistrifluoromethylphenylborate.

8. In paragraph 1, The solution polymerization method of the above ethylene-α-olefin copolymer is a solution polymerization method of an ethylene-α-olefin copolymer using at least one solvent selected from the group consisting of n-hexane, n-heptane, n-butane, n-pentane, n-octane, and cyclohexane.

9. In paragraph 1, The above ethylene-α-olefin copolymer is a solution polymerization method for an ethylene-α-olefin copolymer, wherein the ethylene-α-olefin copolymer is copolymerized with ethylene and at least one α-olefin selected from the group consisting of 1-octene, 1-hexene, and 1-butene.

10. In paragraph 1, The above ethylene-α-olefin copolymer is a solution polymerization method of an ethylene-α-olefin copolymer having 50 to 99 mol% of ethylene repeating units with respect to the total repeating units.

11. In paragraph 1, The above ethylene-α-olefin copolymer is a solution polymerization method of an ethylene-α-olefin copolymer having a melt flow index of 0.1 to 1,500 g / 10 min at a load of 2.16 kg as measured by ASTM D1238.

12. In paragraph 1, The solution polymerization method of the above ethylene-α-olefin copolymer comprises the steps of: a) preparing an α-olefin composition by mixing an α-olefin in a solvent; and b) A solution polymerization method for an ethylene-α-olefin copolymer, comprising a step of adding a catalyst composition to the above α-olefin composition and adding ethylene into a reactor to polymerize an ethylene-α-olefin copolymer.

13. In paragraph 12, The solution polymerization method of the above ethylene-α-olefin copolymer is a solution polymerization method of the ethylene-α-olefin copolymer in which hydrogen is additionally added in step b).

14. In paragraph 1, A solution polymerization method for the above ethylene-α-olefin copolymer further comprises at least one aluminum scavenger selected from the group consisting of trimethylaluminum, triethylaluminum, tripropylaluminum, triisobutylaluminum, and trihexylaluminum.

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