Method for producing branched polyolefins

Abstract

This disclosure provides a process. In one embodiment, the process comprises contacting a first polymerization catalyst and a first co-catalyst with (i) an ethylene monomer and an optional α-olefin comonomer, and (ii) a double-headed aluminum-alkyl chain transfer agent, under first polymerization conditions in a first polymerization reactor at a temperature below 150°C. The process comprises first forming one or more telechelic aluminum-terminated polymer chains and supplying one or more telechelic aluminum-terminated polymer chains to a second polymerization reactor. The second polymerization reactor has second polymerization conditions, a second polymerization catalyst, a second co-catalyst, and a temperature of 160°C to 250°C. The process comprises contacting (iii) an ethylene monomer and an optional olefin comonomer, and (iv) one or more telechelic aluminum-terminated polymer chains in the second polymerization reactor. The process is greater than 8.0 10 This involves forming an ethylene-based polymer having a vinyl content of over 20 / 1,000,000C and 20 / 1,000,000C.

Description

[Technical Field]

[0001] Olefin polymers with long-chain branching (LCB) are olefin polymers that contain one or more side-chain branches whose length is comparable to or longer than the critical entanglement length. It is known that the incorporation of long-chain branching (LCB) improves processability and increases melt strength in olefin polymers.

[0002] Compared to linear olefin polymers of the same molecular weight, olefin polymers with LCB exhibit higher shear sensitivity, higher zero-shear viscosity, greater melt elasticity, greater impact strength, and higher melt strength ("melt strength" is the resistance to stretching during the extension of a molten olefin polymer). High melt strength is a desirable mechanical property in thermoforming, extrusion coating, and blow molding processes involving olefin polymers.

[0003] Furthermore, olefin polymers containing LCB exhibit higher viscosity at low shear rates and lower viscosity at high shear rates compared to linear olefin polymers with the same molecular weight. Shear reduction is advantageous in polymer processing under high shear conditions.

[0004] For linear low-density polyethylene (LLDPE), the common mechanism by which LCBs are formed during olefin coordination polymerization (a form of addition polymerization mediated by transition metal catalysts) is the insertion of vinyl-terminated polymer chains generated by thermal termination at the transition metal catalyst site. The level of LCB formed by this mechanism is usually low due to the small population of vinyl-terminated polymer chains. In contrast, low-density polyethylene (LDPE) produced by free radical polymerization is known for its excellent processability due to its unique "dendritic" branch-on-branch structure. It is known that α,ω-dienes such as decadienes can be added during olefin polymerization to crosslink two polymer chains. The α,ω-diene approach is disadvantageous because it increases the risk of gelation in the reactor system and imposes logistical burdens due to the limited availability and high cost of α,ω-dienes in industrial-scale quantities.

[0005] In this technical field, there is a recognized need for alternative processes to generate long-chain branching in olefinic polymers. In particular, there is a need for a process to generate long-chain branching in olefinic polymers (especially ethylene-based polymers) by coordination polymerization of olefins. [Overview of the project]

[0006] The present disclosure provides a process. In one embodiment, the process comprises contacting a first polymerization catalyst and a first cocatalyst with (i) an ethylene monomer and an optional α-olefin comonomer, and (ii) a di-functional aluminum-alkyl chain transfer agent, under first polymerization conditions in a first polymerization reactor at a temperature below 150°C. The process includes first forming one or more telechelic aluminum-terminated polymer chains and feeding the one or more telechelic aluminum-terminated polymer chains to a second polymerization reactor. The second polymerization reactor has second polymerization conditions, a second polymerization catalyst, a second cocatalyst, and a temperature of 160°C to 250°C. The process includes contacting, in the second polymerization reactor, (iii) an ethylene monomer and an optional olefin comonomer, and (iv) one or more telechelic aluminum-terminated polymer chains. The process includes forming an ethylene-based polymer having an I / I2 greater than 8.0 and a vinyl content greater than 20 / 1,000,000C. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] [Figure 1] FIG. 1 is a chart showing the chemical structures of different types of carbon-carbon double (unsaturations in the polymer chain) bonds of vinylene, trisubstituted, vinyl, and vinylidene. [Figure 2] FIG. 13 is a schematic diagram of a polymerization process according to an embodiment of the present disclosure. [Figure 3] FIG. 16 is a schematic diagram of a dual reactor polymerization system according to an embodiment of the present disclosure. <​​​​​​​​​​​​​All references to the periodic table refer to the version published by CRC Press, Inc., 1990–1991. References to element groups in this table refer to a new notation used to number the groups.

[0009] For the purposes of U.S. patent practice, the content of any referenced patent, patent application, or publication is incorporated herein by reference in its entirety, particularly with respect to the disclosure of definitions and general knowledge in the art (to the extent that it does not contradict any definitions specifically provided herein) (or the corresponding U.S. patent application of the publication is incorporated by reference in the same way).

[0010] Numerical ranges disclosed herein include all values ​​from the lower limit to the upper limit (including the lower and upper limits). In the case of a range that includes an explicit value (e.g., 1 or 2, or 3 to 5, or 6 or 7), any sub-range between any two explicit values ​​(e.g., in the case of the range 1 to 7 above, this includes sub-ranges such as 1 to 2, 2 to 6, 5 to 7, 3 to 7, 5 to 6, etc.).

[0011] Unless otherwise objected, and unless implied by the context, all parts and percentages are based on weight, and all test methods are current as of the filing date of this disclosure.

[0012] As used herein, "alkyl group" refers to a saturated hydrocarbonyl group.

[0013] As used herein, the terms “blend” or “polymer blend” refer to a blend of two or more polymers. Such a blend may or may not be miscible (i.e., not phase-separated at the molecular level). Such a blend may or may not be phase-separated. Such a blend may or may not contain one or more domain configurations as determined by transmission electron spectroscopy, light scattering, X-ray scattering, and other methods well known in the art.

[0014] The term "composition" refers to a mixture of materials that constitute a composition, as well as reaction products and decomposition products formed from the materials of the composition.

[0015] The terms “comprising,” “including,” and “having,” and their derivatives, are not intended to exclude the presence of any additional components, processes, or procedures, whether or not they are specifically disclosed. To avoid any doubt, all compositions claimed through the use of the term “comprising” may, unless otherwise stated, include any additional additives, adjuvants, or compounds, whether or not they are polymers. In contrast, the term “consisting essentially of” excludes any other components, processes, or procedures from the scope of any prior description, except those not essential for operability. The term “consisting of” excludes any components, processes, or procedures that are not specifically described or enumerated. The term “or” refers to the enumerated members individually and in any combination, unless otherwise stated. The use of the singular includes the use of the plural, and vice versa.

[0016] The term "ethylene-based polymer" and similar terms refer to polymers that, based on the total weight of the polymer, contain a majority by weight percentage of ethylene-derived units in polymeric form. Non-limiting examples of ethylene-based polymers include low-density polyethylene (or ethylene homopolymer, or long-chain branching with a density of 0.915 g / cc to 0.940 g / cc and a broad MWD, typically produced by high-pressure free radical polymerization) and at least one C3-C 10 α-olefin, preferably an ethylene / α-olefin copolymer containing C3-C4 ("LDPE"), linear low-density polyethylene (or "LLDPE"), units derived from ethylene and at least one C3-C4 10Linear ethylene / α-olefin copolymers (LLDPE), which contain a heterogeneous short-chain branching distribution including units derived from α-olefin comonomers, or at least one C4-C8 α-olefin comonomer, or at least one C6-C8 α-olefin comonomer, are characterized in that, in contrast to conventional LDPE, long-chain branching is present, if any, only slightly, and LLDPE has densities ranging from 0.880 g / cc, 0.890 g / cc, 0.900 g / cc, 0.910 g / cc, 0.915 g / cc, 0.920 g / cc, 0.925 g / cc to 0.930 g / cc, 0.935 g / cc, or 0.940 g / cc), ultra-low density polyethylene (VLDPE), ultra-low density polyethylene (ULDPE), medium-density polyethylene (or "MDPE") - ethylene homopolymer, or at least one C3-C 10 α-olefins, or ethylene / α-olefin copolymers having a density of 0.926 g / cc to 0.940 g / cc containing C3-C4 α-olefins, high-density polyethylene (or "HDPE") ethylene homopolymers, or at least one C4-C 10 Examples include α-olefin comonomers, or C4-C8 α-olefin comonomers and ethylene / α-olefin copolymers having densities of 0.94 g / cc, 0.945 g / cc, 0.95 g / cc, or greater than 0.955 g / cc but less than 0.96 g / cc, or 0.97 g / cc, or 0.98 g / cc.

[0017] A "heteroatom" is an atom other than carbon and hydrogen. Heteroatoms can be non-carbon atoms from groups IV, V, VI, and VII of the periodic table. Non-restrictive examples of heteroatoms include F, N, O, P, B, S, and Si.

[0018] A "hydrocarbon" is a compound containing only hydrogen and carbon atoms. A "hydrocarbonyl" (or "hydrocarbonyl group") is a hydrocarbon with a bond value (typically monovalent). Hydrocarbons can have linear, cyclic, or branched structures.

[0019] An "interpolymer" is a polymer prepared by the polymerization of at least two different monomers. This general term includes polymers prepared from two different monomers, and copolymers, which are commonly used to refer to polymers prepared from more than two different monomers, such as terpolymers, tetrapolymers, etc.

[0020] The terms "long-chain branching," "LCB," and similar terms refer to branched chains extending from the polymer backbone, each containing more than one carbon atom. If the polymer is a copolymer (e.g., ethylene / α-olefin copolymer), the LCB contains one more carbon atom and two less carbon atoms than the total length of the longest comonomer copolymerized with ethylene. For example, in ethylene / octene copolymer, the LCB is at least seven carbon atoms long. In practice, the LCB is longer than the side chains resulting from the incorporation of comonomers into the polymer backbone. The polymer backbone of HPLDPE contains bonded ethylene units.

[0021] An "olefin polymer" or "polyolefin" is a polymer containing more than 50 weight percent of polymerizable olefin monomers (based on the total amount of polymerizable monomers), and may optionally contain at least one comonomer. Non-limiting examples of olefin polymers include ethylene polymers or propylene polymers.

[0022] A "polymer" is a compound prepared by polymerizing monomers that provide a plurality of and / or repeating "units" or "mer units" that make up the polymer, whether of the same type or different types. Thus, the general term "polymer" encompasses the term "homopolymer", which is commonly used to refer to a polymer prepared from only one type of monomer, and the term "copolymer", which is commonly used to refer to a polymer prepared from at least two types of monomers. It also encompasses all forms of copolymers, such as random, block, etc. The terms "ethylene / α-olefin polymer" and "propylene / α-olefin polymer" each denote the above-mentioned copolymers prepared by polymerizing ethylene or propylene with one or more additional polymerizable α-olefin monomers. Polymers are often referred to as being "made of", "based on", "containing" a specified monomer or type of monomer, etc., but in this context, it should be noted that the term "monomer" is understood to refer to the specified monomer of the polymerization residue and not to non-polymerized species. Generally, polymers herein are based on "units" that are the polymerized form of the corresponding monomers.

[0023] Test Methods 1 1H NMR. 1 1H nuclear magnetic resonance 1 1H nuclear magnetic resonance, 1¹H NMR detects the following types of carbon-carbon double bonds ("unsaturated") in polymers: "Vinylene" is a carbon-carbon double bond having the formula R1-CH=CH-R2, where R1 and R2 are carbon atoms or heteroatoms selected from N, O, P, B, S, and Si, respectively. "Trisubstituted" is a carbon-carbon double bond in which the carbon of the double bond is bonded to a total of three carbon atoms, where R1, R2, and R3 (in Figure 1) are carbon atoms, respectively. "Vinyl" is a carbon-carbon double bond having the formula R-CH=CH2 (where R is a carbon atom or heteroatom selected from N, O, P, B, S, and Si). "Vinylidene" is a carbon-carbon double bond having the formula C=CH2. "Total unsaturation" (or "total") is the sum of vinylene, trisubstituted, vinyl, and vinylidene in the polymer. The chemical structures of vinylene, trisubstituted, vinyl, and vinylidene are given in Figure 1.

[0024] 1 Polymer samples for 1H NMR analysis were prepared by adding 130 mg of the sample to 3.25 g of 50 / 50 wt tetrachloroethane-d2 / perchloroethylene containing 0.001 M Cr(AcAc)3 in a 10 mm NMR tube. To prevent oxidation, the sample was purged by passing N2 through the solvent for approximately 5 minutes using a pipette inserted into the tube, then the tube was capped and sealed with Teflon tape. To ensure homogeneity, the sample was heated to 115°C and vortexed.

[0025] Using a Bruker AVANCE 400 / 600MHz spectrometer equipped with a Bruker high-temperature CryoProbe, at a sample temperature of 120°C, 11H NMR was performed. To obtain spectra, two experiments were performed: a control spectrum to quantify total polymer protons, and a double pre-saturation experiment to suppress strong polymer backbone peaks and enable a highly sensitive spectrum for quantification of end groups. The control was performed with a ZG pulse, 4 scans, SWH 10,000 Hz, AQ 1.64 s, D 114 s. The double pre-saturation experiment was performed with a modified pulse sequence, lc1prf2.zz1, TD32768, 100 scans, DS4, SWH 10,000 Hz, AQ 1.64 s, D 11 s, D 13 The test was performed in 13 seconds. The results are reported as the number of vinyl groups per 1,000,000 carbon atoms, i.e., per 1,000,000 C (and the number of vinylene, trisubstituted, vinylidene, and total).

[0026] Density is measured according to ASTM D792, Method B. The results are recorded in grams per cubic centimeter (g / cc).

[0027] Differential scanning calorimetry (DSC). Differential scanning calorimetry (DSC) can be used to measure the melting, crystallization, and glass transition behavior of polymers over a wide range of temperatures. The tests were performed using a TA Instruments DSC2500 equipped with a refrigerator cooling system. Aluminum DSC sealed sample pans were used, and 5–8 mg of sample was added. The tests were performed in a nitrogen environment.

[0028] At the start of the test, the temperature was equilibrated to 180°C and maintained isothermally for 5 minutes to remove thermal history. Next, the temperature was lowered to -40°C at a rate of 10°C / min to determine the crystallization temperature. After reaching the final temperature, it was held for 5 minutes. Finally, the temperature was raised back up to 180°C at a rate of 10°C / min to determine the melting point of the polymer.

[0029] Triple Detector GPC (TD-GPC). The chromatography system for triple detector gel permeation chromatography (TD-GPC) consisted of a PolymerChar GPC-IR (Valencia, Spain) high-temperature GPC chromatograph equipped with an internal IR5 infrared detector (IR5). The autosampler's oven compartment was set to 160°C, and the column compartment to 150°C. The columns used were four Agilent "Mixed A" 30 cm, 20 micron linear mixed-bed columns and a 20 μm pre-column. The chromatography solvent used was 1,2,4-trichlorobenzene containing 200 ppm butylated hydroxytoluene (BHT). The solvent source was spurged with nitrogen. The injection volume used was 200 microliters, and the flow rate was 1.0 ml / min.

[0030] The GPC column set was calibrated using 21 polystyrene standards with a narrow molecular weight distribution ranging from 580 to 8,400,000, placed in six "cocktail" mixtures with at least a 10-fold gap between individual molecular weights. The standards were purchased from Agilent Technologies. Polystyrene standards were prepared using 0.025 grams in 50 ml of solvent for molecular weights above 1,000,000, and 0.05 grams in 50 ml of solvent for molecular weights below 1,000,000. The polystyrene standards were dissolved at 80 degrees Celsius for 30 minutes with gentle stirring. The peak molecular weights of the polystyrene standards were converted to polyethylene molecular weights using Equation 1 (as described in Williams and Ward, J. Polym. Sci., Polym. Let., 6, 621 (1968)):

[0031]

number

[0032] A quintic polynomial was used to fit the respective polyethylene equivalent calibration points. A slight adjustment (approximately 0.375 to 0.445) was made for A to correct the column resolution and band expansion effect so that linear monopolymer polyethylene standards could be obtained at 120,000 Mw.

[0033] The total plate count of the GPC column set was performed using decane (prepared at 0.04 g in 50 ml of TCB and dissolved for 20 minutes with gentle agitation). Plate count (Equation 2) and symmetry (Equation 3) were measured in 200 microliter injections according to the following equations:

[0034]

number

[0035] The sample was prepared semi-automatically using PolymerChar's "Instrument Control" software, with a target weight of 2 mg / mL. The solvent (containing 200 ppm BHT) was added to a vial with a pre-nitrogen-spurged septum cap via a PolymerChar high-temperature autosampler. The sample was dissolved at 160°C for 2 hours with slow shaking.

[0036] Mn (GPC) , Mw (GPC) , and Mz (GPC) The calculations were based on GPC results using the internal IR5 detector (measurement channel) of the PolymerChar GPC-IR chromatograph, according to Equations 4 to 6, using PolymerChar's GPCOne® software, IR chromatograms with baselines subtracted at each equally spaced data acquisition point (i), and polyethylene equivalent molecular weights obtained from the narrow standard calibration curve for point (i) in Equation 1.

[0037]

number

[0038] To monitor deviations over time, a flow rate marker (decane) was introduced into each sample via a micropump controlled by the PolymerChar GPC-IR system. Using this flow rate marker (FM), the pump flow rate (nominal flow rate) for each sample was linearly corrected by matching the RV (RV(FM sample)) of each decane peak in the sample with the RV (RV(FM calibrated)) of the calibrated decane peak in the narrow standard material. It was assumed that any temporal change in the decane marker peak corresponds to a linear shift in the flow rate (effective flow rate) over the entire run. To facilitate the highest accuracy of RV measurement of the flow marker peak, the flow marker concentration chromatogram peaks were fitted to a quadratic equation using the least-squares fitting method. The true peak location was then solved using the first derivative of the quadratic equation. After calibrating the system based on the flow rate marker peaks, the effective flow rate (relative to the narrow standard calibration) was calculated as shown in Equation 7. The processing of the flow rate marker peaks was performed via PolymerChar GPCOne® software. The acceptable flow rate correction should be such that the effective flow rate is within ±1% of the apparent flow rate.

[0039] Effective flow rate = Nominal flow rate * (RV (Calibrated FM) / RV (FM sample)) (Equation 7)

[0040] Meltflow Index ( I 2. I 10 ) were measured according to ASTM method D1238. I2 and I 10 The measurements were taken at 190°C / 2.16 kg and 190°C / 10 kg, respectively. The results are reported as grams of elution per 10 minutes, i.e., g / 10 min.

[0041] Dynamic mechanical analysis (DMA) was performed using an ARES-G2 rheometer with two parallel plates of 25 mm diameter. The tests were conducted at 190°C, using a 1.8 mm gap, at a frequency interval ranging from 0.1 to 100 rad / s, and under a 10% strain. By applying this deformation and measuring the resulting torque with a transducer, parameters such as complex viscosity, storage modulus, and loss modulus at specific shear conditions were determined.

[0042] Detailed explanation This disclosure provides a process. In one embodiment, a process is provided which includes contacting a first polymerization catalyst and a first co-catalyst with (i) an ethylene monomer and an optional α-olefin comonomer, and (ii) a double-headed aluminum-alkyl chain transfer agent, under first polymerization conditions in a first polymerization reactor at a temperature below 150°C, to first form one or more telechelic aluminum-terminated polymer chains, and supplying one or more telechelic aluminum-terminated polymer chains to a second polymerization reactor having second polymerization conditions, a second polymerization catalyst, a second co-catalyst, and a temperature of 160°C to 250°C. The process includes contacting (iii) an ethylene monomer and an optional olefin comonomer, and (iv) one or more telechelic aluminum-terminated polymer chains in the second polymerization reactor, and I greater than 8.0 10 This includes forming an ethylene-based polymer having a vinyl content of / I2 and over 20 / 1,000,000C.

[0043] The process involves contacting a first polymerization catalyst and a first co-catalyst with (i) olefin monomers and optionally selected olefin comonomers, and (ii) a double-headed aluminum-alkyl chain transfer agent, under first polymerization conditions in a first polymerization reactor at a temperature below 150°C. As used herein, the term “polymerization conditions” refers to process parameters when ethylene (and optionally selected olefin comonomers) are copolymerized in the presence of the catalyst system. Examples of first polymerization conditions include those that affect polymerization reactor conditions (reactor type), reactor pressure, reactor temperature, reagent and polymer concentrations, solvent, support, residence time and distribution, molecular weight distribution and polymer structure. As used herein, the term “first polymerization conditions” includes polymerization temperatures of below 150°C, or 85°C to 150°C, or 90°C to 140°C, or 100°C to 135°C, or 110°C to 130°C.

[0044] In one embodiment, the first polymerization catalyst has formula (1), Formula (1)

[0045] [ka] In the formula, X 1 Each instance is a halide, N,N-dimethylamide, or C1-4 alkyl, preferably each instance is X 1 It is methyl, R1~R7 are independently hydrogen, halogen, and C1~C 20 Alkyl, or C6-C 20 It is either aryl, or two adjacent R groups are joined together to form a ring.

[0046] In one embodiment, the first polymerization catalyst has formula (2)

[0047] [ka]

[0048] The first polymerization condition includes providing a first co-catalyst. Non-limiting examples of preferred first co-catalysts include boron compounds that can be used as activation co-catalysts in the preparation of the improved catalysts of this disclosure, including trisubstituted ammonium salts, such as trimethylammonium tetrakis(pentafluorophenyl)borate, triethylammonium tetrakis(pentafluorophenyl)borate, tripropylammonium tetrakis(pentafluorophenyl)borate, tri(n-butyl)ammonium tetrakis(pentafluorophenyl)borate, tri(sec-butyl)ammonium tetrakis(pentafluorophenyl)borate, N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate, N,N-dimethylanilinium n-butyltris(pentafluorophenyl)borate, N,N-dimethylanilinium benzyltris(pentafluorophenyl)borate, N,N-dimethylanilinium tetrakis(4-(t-butyldimethylsilyl)-2,3,5,6-tetrafluorophenyl)borate, N ,N-dimethylanilinium tetrakis(4-(triisopropylsilyl)-2,3,5,6-tetrafluorophenyl) borate, N,N-dimethylanilinium pentafluorophenoxytris(pentafluorophenyl) borate, N,N-diethylanilinium tetrakis(pentafluorophenyl) borate, N,N-dimethyl-2,4,6-trimethylanilinium tetrakis(pentafluorophenyl) borate, dimethyloctadecylammonium tetrakis(pentafluorophenyl) borate, methyldioctadecylammonium tetrakis(pentafluorophenyl) borate; multiple dialkylammonium salts, e.g., di-(i-propyl)ammonium tetrakis(pentafluorophenyl) borate, methyloctadecylammonium tetrakis(pentafluorophenyl) borate, methyloctadecylammonium tetrakis(pentafluorophenyl) borate, and dioctadecylammonium tetrakis(pentafluorophenyl) borate;Examples include various trisubstituted phosphonium salts, such as triphenylphosphonium tetrakis(pentafluorophenyl)borate, methyl dioctadecylphosphonium tetrakis(pentafluorophenyl)borate, and tri(2,6-dimethylphenyl)phosphonium tetrakis(pentafluorophenyl)borate; disubstituted oxonium salts, such as diphenyloxonium tetrakis(pentafluorophenyl)borate, di(o-tolyl)oxonium tetrakis(pentafluorophenyl)borate, and di(octadecyl)oxonium tetrakis(pentafluorophenyl)borate; and disubstituted sulfonium salts, such as di(o-tolyl)sulfonium tetrakis(pentafluorophenyl)borate and methyloctadecylsulfonium tetrakis(pentafluorophenyl)borate.

[0049] (i) an ethylene monomer and (ii) an optional olefin comonomer are polymerized under the first polymerization conditions. Non-limiting examples of preferred olefin comonomers include α-olefins having 3 to 30 carbon atoms, or 3 to 20 carbon atoms, or 3 to 10 carbon atoms, or 4 to 8 carbon atoms. In one embodiment, an olefin comonomer is present, and the olefin comonomer is selected from propylene, butene, hexene, and octene, or selected from butene, hexene, and octene.

[0050] In one embodiment, the process includes contacting a first polymerization catalyst and a first co-catalyst with (i) an ethylene monomer and (ii) one or more C3-C8α-olefin comonomers under first polymerization conditions in a first polymerization reactor at a temperature of less than 150°C to eliminate the diene and / or branching agent.

[0051] This process involves contacting a first polymerization catalyst and a first co-catalyst with (i) an olefin monomer and an optionally selected olefin comonomer, and (ii) a double-headed aluminum-alkyl chain transfer agent, under first polymerization conditions at a temperature below 150°C. As used herein, "chain transfer agent" refers to a compound in which a polymeryl group (e.g., alkyl group) in the chain transfer agent can be exchanged for a growing polymer chain in the catalyst, resulting in the cessation of polymer chain growth under first polymerization conditions. As used herein, "double-headed aluminum-alkyl chain transfer agent" is a chain transfer agent having formula A,

[0052] [ka] During the ceremony, n is a number between 1 and 100. R1 is a divalent linear, branched, or cyclic C4-C 100 A hydrocarbyl group, optionally containing at least one heteroatom, and being aliphatic or aromatic, R2, R3, R4, and R5 are each independently hydrogen, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. R2 and R3, and R4 and R5 may bond to each other to form a divalent C4-C100 ring. Non-limiting examples of double-headed aluminum-alkyl chain transfer agents include the structures (B), (C), (D), and (E) shown below.

[0053] [ka]

[0054] [ka]

[0055] [ka] m is an integer between 1 and 100, or between 1 and 10; and / or

[0056] [ka] m is an integer between 1 and 100, or between 1 and 10.

[0057] Figure 2 is a schematic diagram of the process. Under first polymerization conditions in a first polymerization reactor ("reactor-1") at a temperature below 150°C (or 135°C), contact occurs between a first polymerization catalyst, a first co-catalyst, an ethylene monomer (and an optional olefin comonomer) or octene, and a double-headed aluminum-alkyl chain transfer agent. Alkyl groups on the aluminum migrate to the catalyst, grow from both ends into polymer chains, and migrate back to the aluminum, forming one or more telechelic aluminum-terminated polymer chains 12. As used herein, "telechelic aluminum-terminated polymer chain" is a polymer or prepolymer chain having at least two ends that can enter into further polymerization or other reactions via their reactive end groups, wherein the polymer or prepolymer contains aluminum metal at at least two ends of the chain.

[0058] The second polymerization catalyst is resilient to olefin polymerization at high temperatures, i.e., 160°C to 250°C. In one embodiment, the second polymerization catalyst has formula (3),

[0059] [ka] During the ceremony, M is titanium, zirconium, or hafnium. Each Y 1 and Y 2 (C1~C 40 ) Hydrocarbyl, (C1~C 40) independently selected from the group consisting of trihydrocarbylsilylhydrocarbyl, halogen, alkoxide, or amine, or two Y groups together are a divalent hydrocarbylene, hydrocarbadiyl, or trihydrocarbylsilyl group. Each Ar 1 and Ar 2 (C6~C 40 ) Aryl, substitution (C6~C 40 )Aaryl, (C3~C 40 ) Heteroaryls, and substitutions (C3~C 40 ) Selected from the group consisting of heteroaryls, T 1 It is a divalent bridging group of 2 to 20 carbon atoms, independently containing heteroatoms containing Si, Ge, O, N, S, and P in each occurrence, at arbitrary selection. Each R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , and R 14 These are, independently, hydrogen, halogens, (C1~C 40 ) Hydrocarbyl substitution (C1~C 40 ) Hydrocarbyl, (C1~C 40 ) Heterohydrocarbyl, substitution (C1~C 40 ) Heterohydrocarbyl, (C6~C 40 ) Aryl, substitution (C6~C 40 )Aaryl, (C3~C 40 ) Heteroaryls, and substitutions (C3~C 40 ) Selected from the group consisting of heteroaryls and nitro (NO2).

[0060] In one embodiment, the second polymerization catalyst has formula (4).

[0061] [ka]

[0062] The second polymerization condition includes providing a second co-catalyst. A non-limiting example of a suitable second co-catalyst is a co-catalyst suitable for use with the first polymerization catalyst.

[0063] (i) an ethylene monomer and (ii) an optional olefin comonomer are polymerized under second polymerization conditions. Non-limiting examples of preferred olefin comonomers include α-olefins having 3 to 30 carbon atoms, or 3 to 20 carbon atoms, or 3 to 8 carbon atoms, or 4 to 8 carbon atoms. In one embodiment, an olefin comonomer is present, selected from propylene, 1-butene, 1-hexene, and 1-octene, or selected from 1-butene, 1-hexene, and 1-octene.

[0064] The process involves supplying one or more telechelic aluminum-terminated polymer chains 12 (from a first polymerization reactor) to a second polymerization reactor, or transferring them by other means. The telechelic aluminum-terminated polymer 12 is either supplied directly to the second polymerization reactor or flows directly into the second polymerization reactor. The second polymerization reactor has second polymerization conditions, a second polymerization catalyst, a second co-catalyst, and a temperature of 160°C to 250°C. As used herein, the term “second polymerization conditions” refers to the process parameters when ethylene (and optionally selected olefin comonomers) are copolymerized in the second polymerization reactor in the presence of a second catalyst system, and the second polymerization conditions are different from the first polymerization conditions. In particular, the second polymerization conditions include parameters such as polymerization reactor conditions (reactor type), reactor pressure, reactor temperature, reagent and polymer concentrations, solvent, support, residence time and distribution, and one or more parameters in the second polymerization conditions are different from the respective parameters in the first polymerization conditions. The second polymerization condition affects the molecular weight distribution and polymer structure. As used herein, the term “second polymerization condition” includes polymerization temperatures of 160°C to 250°C, 180°C to 230°C, or 190°C to 220°C.

[0065] Referring to Figure 2, in a second polymerization reactor ("main reactor" in Figure 2) under second polymerization conditions at a temperature of 160°C to 250°C (or 190°C), the process includes contacting a plurality of aluminum-terminated polymer chains 12 with ethylene monomers (and optionally selected olefin comonomers, or octene) to form one or more growing polymer chains 14. When the first polymerization catalyst effectively performs chain transfer with a double-headed aluminum-alkyl chain transfer agent, the second polymerization catalyst provides (1) resilience to polymerization at high temperatures (160°C to 250°C), and (2) the ability to incorporate vinyl-terminated polymer chains.

[0066] In one embodiment, ethylene ("C2=") and an optional olefin comonomer, octene ("C8="), as shown in Figure 2, are present. The growing polymer chain 14 is an ethylene / octene copolymer. As the polymer chain 14 grows, simultaneously or substantially simultaneously, multiple aluminum-terminated polymer chains 12 are converted to one or more polymeric chains or polymericdienes 12a. Although not bound by any particular theory, it is thought that under second polymerization conditions (and second polymerization temperatures of 160°C to 250°C), the aluminum-terminated polymer chains 12 undergo β-hydride elimination to form double vinyl-terminated polymeric chains 12a (or "polymericdienes"). In the second polymerization reactor, under second polymerization conditions, the vinyl-terminated polymeric chains 12a are incorporated into the growing polymer chain 14, or otherwise inserted, thereby forming an olefinic polymer having H-shaped long-chain branches 16. In one embodiment, the growing polymer chain is an ethylene / octen copolymer, and the vinyl-terminated polymeryl chain 12a is incorporated into the growing ethylene / octen copolymer chain or inserted in other ways to form an ethylene / octen copolymer having H-shaped long-chain branching.

[0067] In one embodiment, the process involves a first polymerization catalyst and a first co-catalyst having the structure of formula (1) under first polymerization conditions in a first polymerization reactor at a temperature of 120°C to 150°C (or 135°C). (i) Ethylene monomers and C3-C8α-olefin comonomers (e.g., octene), and (ii) Contact with a double-headed aluminum-alkyl chain transfer agent (e.g., IPRA), First, form one or more telechelic aluminum-terminated polymer chains, One or more telechelic aluminum-terminated polymer chains are supplied to a second polymerization reactor having second polymerization conditions, a second polymerization catalyst having the structure of formula (2), a second co-catalyst, and a temperature of 180°C to 230°C (or 190°C). In the second polymerization reactor, (iii) Ethylene monomers and C3-C8α-olefin comonomers (e.g., octene), and (iv) Contacting one or more telechelic aluminum-terminated polymer chains, (i) I of 8.5-20.0, or 9.0-15.0, or 9.3-13.2 10 / I2, and / or (ii) Vinyl content of 25 / 1,000,000C to 100 / 1,000,000C, or 30 / 1,000,000C to 90 / 1,000,000C, or 35 / 1,000,000C to 80 / 1,000,000C, and / or (iii) Forming an ethylene-based polymer having an Mw / Mn ratio of 2.4 to 4.0, or 2.5 to 3.5, or 2.6 to 3.4.

[0068] Some embodiments of this disclosure are described in detail below, without limitation, as examples. [Examples]

[0069] Table 1 below provides the catalysts, co-catalysts, and di-aluminum-alkyl chain transfer agents used to prepare comparative samples (CS) A to C and examples (IE) 1 to 5 of the present invention.

[0070] [Table 1]

[0071] Polymerization of ethylene / octen copolymers having LCBs An ethylene-based polymer having H-shaped long-chain branching was synthesized using a first polymerization reactor, which was a well-mixed high-pressure autoclave reactor, and a second polymerization reactor, which was a well-mixed high-pressure autoclave reactor. The first and second polymerization reactors were configured in series as shown in Figure 3 (hereinafter interchangeably referred to as the "dual reactor system"). The purified solvent Isopar-E, ethylene monomer, and octen comonomer were mixed with a chain transfer agent (CTA) and injected into the first polymerization reactor with a capacity of 5 liters.

[0072] A first polymerization catalyst (catalyst 1), a borate activator, a double-headed aluminum-alkyl chain transfer agent (IPRA), an ethylene monomer, and an octen comonomer were introduced into a first polymerization reactor to produce telechelic aluminum-terminated polymer chains.

[0073] The telechelic aluminum-terminated polymer chains were transferred to a second polymerization reactor. The second polymerization reactor was supplied with a second polymerization catalyst (catalyst 2), a borate activator, ethylene, octene, and hydrogen to produce ethylene / octene copolymer growth chains. The telechelic aluminum-terminated polymer chains underwent β-hydride elimination at high temperatures in the second polymerization reactor (190°C) to form divinyl polymeric chains or polymeric dienes.

[0074] Divinyl polymeryl chains were incorporated and the growing ethylene / octene polymer chains were crosslinked to form ethylene / octene copolymers with long-chain branching and ethylene / octene copolymers with H-shaped branching.

[0075] The effluent from the second polymerization reactor consists of polymer, solvent, and unreacted reagents such as monomers, comonomers, hydrogen, aluminum-alkyl chain transfer agents (IPRA), and catalyst components. The effluent from the second polymerization reactor is sent to a destorage unit to remove the solvent and unreacted monomers. Either water or isopropyl alcohol (IPA) is added to the effluent to neutralize the remaining catalyst components and metal alkyls.

[0076] In comparative sample 1 (CS1), the first polymerization reactor was not used. Using catalyst 2, the CS1 polymer was produced using only the second polymerization reactor. IE1-5 were produced using the "dual reactor system" described above. The polymerization conditions are provided in Tables 2 and 3 below, where "R1" is the first polymerization reactor and "R2" is the second polymerization reactor.

[0077] [Table 2]

[0078] [Table 3]

[0079] [Table 4]

[0080] Examples (IE) IE1-5 of the present invention were produced by increasing the amount of telechelic aluminum-terminated polymer chains, which are products of the first reactor, and supplying them to the second reactor. 10 The I2 ratio increased, indicating the formation of branched polymers. As is evident from the significantly higher amount of vinyl groups in the IE1-IE5 samples, the telechelic aluminum-terminated polymer chains were converted to polymer dienes in the second reactor.

[0081] The DMS analysis of the products is shown in Figure 4. The polymers of the present invention produced from IE1-5 exhibit significantly different rheological behavior compared to the linear polymer produced from CS1, such as higher shear reduction and lower tan-δ values. This is consistent with the behavior of branched polymers.

[0082] This disclosure is not limited to the embodiments and examples contained herein, but is specifically intended to include some embodiments and modified forms of those embodiments, including combinations of elements of different embodiments, to the extent that they fall within the scope of the following claims.

Claims

1. It is a process, Under first polymerization conditions in a first polymerization reactor at a temperature of less than 150°C, the first polymerization catalyst and the first co-catalyst are... (i) Ethylene monomers and optionally selected α-olefin comonomers, (ii) Contact with a double-headed aluminum-alkyl chain transfer agent, The first step is to form one or more telechelic aluminum-terminated polymer chains, The one or more telechelic aluminum-terminated polymer chains are supplied to a second polymerization reactor having second polymerization conditions, a second polymerization catalyst, a second co-catalyst, and a temperature of 160°C to 250°C. In the second polymerization reactor, (iii) Ethylene monomers and optionally selected olefin comonomers, and (iv) Contacting one or more telechelic aluminum-terminated polymer chains, I above 8.0 １０ / I ２ A process comprising forming an ethylene-based polymer having a vinyl content of more than 20 / 1,000,000C.

2. The contact within the second polymerization reactor is Forming one or more growing polymer chains, Converting one or more double-ended aluminum-terminated polymer chains into one or more divinyl polymeryl chains, Incorporating one or more divinyl polymeryl chains into the growing polymer chain, I above 8.0 １０ / I ２ The process according to claim 1, comprising forming an ethylene-based polymer having a vinyl content of more than 20 / 1,000,000C.

3. The first polymerization catalyst is 【Chemistry 1】 It has a structure, In the formula, X １ Each instance of this is a halide, N,N-dimethylamide, or C １ ~ ４ It is alkyl, R １ to R ７ each independently represents hydrogen, halogen, C １ to C ２０ alkyl, or C ６ to C ２０ aryl, or two adjacent R groups join together to form a ring, the process according to claim 1 or 2.

4. The process according to any one of claims 1 to 3, wherein the first polymerization catalyst has the structure of formula (2). 【Chemistry 2】

5. The aforementioned dialuminum-alkyl chain transfer agent is 【Transformation 3】 【Chemistry 4】 【Transformation 5】 (In the formula, m is an integer between 1 and 100.) 【Transformation 6】 (wherein m is an integer between 1 and 100), and The process according to any one of claims 1 to 4, having a structure selected from the group consisting of these combinations.

6. The second polymerization catalyst is of formula (3) 【Transformation 7】 It has a structure, During the ceremony, M is titanium, zirconium, or hafnium. Each Y １ and Y ２ is, (C １ ~C ４０ ) Hydrocarbyl, (C １ ~C ４０ ) independently selected from the group consisting of trihydrocarbylsilylhydrocarbyl, halogen, alkoxide, or amine, or the two Y groups together are a divalent hydrocarbylene, hydrocarbadiyl, or trihydrocarbylsilyl group. Each Ar １ and Ar ２ (C ６ ~C ４０ ) Aryl, substitution (C ６ ~C ４０ ) Aryl, (C ３ ~C ４０ ) heteroaryl and substituted (C ３ ~C ４０ ) Selected from the group consisting of heteroaryls, T １ It is a divalent bridging group of 2 to 20 carbon atoms, independently containing, at any choice, a heteroatom containing Si, Ge, O, N, S, and P in each occurrence. Each R １ , R ２ , R ３ , R ４ , R ５ , R ６ , R ７ , R ８ , R ９ , R １０ , R １１ , R １２ , R １３ , and R １４ These are, independently, hydrogen, halogen, (C １ ~C ４０ ) Hydrocarbyl, substitution (C １ ~C ４０ ) Hydrocarbyl, (C １ ~C ４０ ) Heterohydrocarbyl, substitution (C １ ~C ４０ ) Heterohydrocarbyl, (C ６ ~C ４０ ) Aryl, substitution (C ６ ~C ４０ ) Aryl, (C ３ ~C ４０ ) heteroaryl and substituted (C ３ ~C ４０ ) heteroaryl and nitro(NO ２ A process according to any one of claims 1 to 5, selected from the group consisting of ).

7. The process according to any one of claims 1 to 6, wherein the second polymerization catalyst has the structure of formula (4). 【Transformation 8】

8. The above-mentioned optional α-olefin comonomer exists, C ４ ~C ８ It is an α-olefin comonomer, and the process described above is (i) I 8.5 to 20.0 １０ / I ２ and, (ii) Ethylene / C having a vinyl content of 25 / 1,000,000C to 100 / 1,000,000C ４ ~C ８ The process according to any one of claims 1 to 7, comprising forming an α-olefin copolymer.

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