Ethylene-based polymer compositions having branching and processes for producing the same

Abstract

The present disclosure provides an ethylene-based polymer composition, which is formed by high pressure (greater than or equal to 100 MPa) free radical polymerization. The ethylene-based polymer composition comprises a mixture of ethylene monomers and hydrocarbon molecules, each hydrocarbon molecule comprising three or more terminal olefin groups. The ethylene-based polymer has a melt index (MI) of 0.1 to 1.0 g / 10 min.

Description

Background Art

[0001] The level of branching in low density polyethylene (LDPE) is mainly attributed to the reactor design and the polymerization conditions used to prepare LDPE. Branching agents have been used to increase the level of branching in LDPE. However, the process conditions required to obtain a modified LDPE with a high level of branching generally result in a final product with a lower degree of crystallinity and a higher content of low molecular weight extractable fractions. Therefore, there is a need for a modified LDPE with a high level of branching that can be prepared under conditions that maintain good polymer properties. Summary of the invention

[0002] The present disclosure provides an ethylene-based polymer composition, which is formed by high pressure (greater than or equal to 100 MPa) free radical polymerization. The ethylene-based polymer composition comprises a mixture of ethylene monomers and hydrocarbon molecules, each hydrocarbon molecule comprising three or more terminal olefin groups. The ethylene-based polymer has a melt index (MI) of 0.1 to 1.0 g / 10 min.

[0003] The present disclosure provides a method. In an embodiment, the method includes reacting a mixture of ethylene monomer and hydrocarbon molecules in a polymerization reactor under free radical polymerization conditions and at a pressure greater than or equal to 100 MPa. Each hydrocarbon molecule includes three or more terminal olefin groups. The method includes forming an ethylene-based polymer having a melt index (MI) of 0.1 to 1.0 g / 10 min. In another embodiment, the hydrocarbon molecule has structure I

[0004] Structure I

[0005]

[0006] wherein n is 3 to 160, and m is 0 to 50.

[0007] definition

[0008] Any reference to the Periodic Table of the Elements is to the Periodic Table as published by CRC Press, Inc., 1990-1991. Reference to a group of elements in the table is made by a new notation for numbering the groups.

[0009] For purposes of U.S. patent practice, the contents of any referenced patent, patent application, or publication are incorporated by reference in their entirety (or their equivalent U.S. versions are incorporated by reference), particularly with respect to disclosure of definitions (to the extent not inconsistent with any definitions specifically provided in this disclosure).

[0010] Numerical ranges disclosed herein include all values ​​from the upper and lower limits, and all values ​​include the upper and lower limits. For ranges containing explicit values ​​(e.g., 1 or 2, or 3 to 5, or 6, or 7), any sub-range between any two explicit values ​​is included (e.g., the above ranges 1 to 7 include 1 to 2; 2 to 6; 5 to 7; 3 to 7; 5 to 6; etc.).

[0011] Unless stated to the contrary, implicit from the context, or customary in the art, all parts and percentages are by weight and all test methods are current as of the filing date of this disclosure.

[0012] The term "composition" refers to a mixture of materials which comprise the composition, as well as reaction products and decomposition products formed from the materials of the composition.

[0013] The terms "comprising", "including", "having" and their derivatives are not intended to exclude the presence of any additional components, steps or procedures, whether or not the components, steps or procedures are specifically disclosed. For the avoidance of any doubt, unless stated to the contrary, all compositions claimed by using the term "comprising" may include any additional additives, adjuvants or compounds, whether in polymeric form or otherwise. In contrast, the term "consisting essentially of excludes any other components, steps or procedures (except those that are not essential to operability) from the scope of any subsequent statements. The term "consisting of" excludes any components, steps or procedures that are not specifically described or listed. Unless otherwise stated, the term "or" refers to the listed members individually and in any combination. The use of the singular includes the use of the plural and vice versa.

[0014] As used herein, the term "polymer" or "polymeric material" refers to a compound prepared by polymerizing monomers, whether monomers of the same type or different types, which provide multiple and / or repeated "units" or "monomer units" constituting the polymer in a polymerized form. Therefore, the general term "polymer" thus encompasses the term "homopolymer", which is usually used to refer to polymers prepared from only one type of monomer, and the term "copolymer", which is usually used to refer to polymers prepared from at least two types of monomers. It also encompasses all forms of copolymers, such as random copolymers, block copolymers, etc. The terms "ethylene / α-olefin polymer" and "propylene / α-olefin polymer" represent copolymers prepared by polymerizing ethylene or propylene and one or more other polymerizable α-olefin monomers, respectively, as described above. It should be noted that although polymers are generally referred to as "made of" one or more specified monomers, "based on" a specified monomer or monomer type, "containing" a specified monomer content, etc., in this context, the term "monomer" should be understood to refer to the polymerized residue of the specified monomer rather than unpolymerized substances. In general, the polymer referred to herein is a "unit" based on the polymerized form of the corresponding monomer.

[0015] Unless stated to the contrary, implicit from the context, or customary in the art, all parts and percentages are by weight and all test methods are current as of the filing date of this application.

[0016] The term "blend" or "polymer blend" as used refers to a mixture of two or more polymers. A blend may be miscible or may be immiscible (not phase separated at the molecular level). A blend may or may not be phase separated. 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 known in the art. A blend may be effected by physically mixing two or more polymers at the macroscopic level (e.g., melt blending resins or compounding) or at the microscopic level (e.g., simultaneously formed in the same reactor).

[0017] As used herein, the term "ethylene / α-olefin copolymer" refers to a copolymer having greater than 50 mole percent polymerized ethylene monomer (based on the total amount of polymerizable monomers) and at least one α-olefin.

[0018] As used herein, the term "ethylene monomer" refers to a chemical unit having two carbon atoms with a double bond therebetween, and each carbon bonded to two hydrogen atoms, wherein the chemical unit is polymerized with other such chemical units to form an ethylene-based polymer composition.

[0019] As used herein, the term "high density polyethylene" (or HDPE) refers to an ethylene-based polymer having a density of at least 0.94 g / cc, or at least 0.94 g / cc to 0.98 g / cc. HDPE has a melt index of 0.1 g / 10 min to 25 g / 10 min. HDPE may include ethylene and one or more C3-C 20 α-olefin comonomers. The comonomers may be linear or branched. Non-limiting examples of suitable comonomers include propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, and 1-octene. HDPE can be produced in slurry, gas phase, or solution reactors using Ziegler-Natta, chromium-based, constrained geometry, or metallocene catalysts. Ethylene / C3–C 20 The α-olefin copolymer includes at least 50% by weight ethylene polymerized therein, or at least 70% by weight, or at least 80% by weight, or at least 85% by weight, or at least 90% by weight, or at least 95% by weight ethylene in polymerized form.

[0020] As used herein, the term "hydrocarbon molecule" refers to a chemical component having only carbon and hydrogen atoms.

[0021] As used herein, the term "linear low density polyethylene" (or "LLDPE") refers to a linear ethylene / α-olefin copolymer containing a heterogeneous distribution of short chain branches, which comprises units derived from ethylene and units derived from at least one C3-C 10 Units of α-olefins or C4-C8 α-olefin comonomers. LLDPE is characterized by having very few long chain branches (if any) compared to conventional LDPE. LLDPE has a density of 0.910 g / cc to less than 0.940 g / cc. Non-limiting examples of LLDPE include TUFLIN TM Linear low density polyethylene resin (available from The Dow Chemical Company), DOWLEX TM Polyethylene resin (available from The Dow Chemical Company) and MARLEX TM Polyethylene (available from Chevron Phillips)

[0022] As used herein, the term "low density polyethylene" (or LDPE) refers to polyethylene having a density of 0.909 g / cc to less than 0.940 g / cc, or 0.917 g / cc to 0.930 g / cc, and long chain branches with a broad molecular weight distribution (MWD greater than 3.0).

[0023] As used herein, the term "terminal olefin group" refers to a double bond between two carbon atoms in a polymer chain, wherein one of the carbons in the double bond is a =CH2 group. The terminal double bond is located at the end and / or branch end of the polymer chain. As used herein, the term "internal olefin group" refers to a 1,2-disubstituted carbon-carbon double bond in which the carbon atoms are in a trans configuration. The internal olefin group is located over the entire length of the polymer chain, but not at the end of the polymer chain or along the branch end of the polymer chain. The amount of terminal olefin groups and internal olefin groups per 1000 carbons is measured by FTIR.

[0024] As used herein, the term "olefin content" refers to the number of terminal olefin groups plus the number of internal olefin groups present in the polymer chain per 1000 carbon atoms.Olefin content is measured by infrared spectroscopy ("FTIR").

[0025] Test Method

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

[0027] Hexane extract

[0028] As used herein, the term "hexane extract" refers to the amount of hexane-soluble material removed from the resulting polymer composition by hexane. Polymer pellets (polymerized without further modification; 2.2 grams per press) were pressed into films with a thickness of 3.0 to 4.0 mils using a Carver press. The pellets were pressed in two stages. The melting stage lasted for 3 minutes at 190°C at 3000 pounds. The compression stage lasted for 3 minutes at 190°C at 40,000 pounds. No residue gloves (PIP*CleanTeam*Cotton Lyle Inspection Gloves, Product Model: 97-501) were worn to prevent residual oil from the operator's hands from contaminating the film. The film was punched into "1 inch x 1 inch" squares and weighed (2.5±0.05g). The film was then extracted in a hexane container in a hot water bath at "49.5±0.5°C" for two hours. After two hours, the membrane was removed, rinsed in clean hexane, and dried in a vacuum oven (80 ± 5 ° C) under full vacuum (ISOTEMP vacuum oven, model 281A, at 30 inches of mercury) for two hours. The membrane was then placed in a desiccator and allowed to cool to room temperature for at least one hour. The membrane was then reweighed and the amount of mass loss due to extraction in hexane was calculated. This method is based on 21 CFR § 177.1520 (d) (3) (ii) with one deviation from the FDA protocol, namely, hexane was used instead of n-hexane. Hexane extracts are reported in wt %.

[0029] Melt force

[0030] The D-MELT device (available from Goettfert GmbH Buchen, Germany) is used to determine the melt force. The D-MELT device includes a commercial plastic meter and a digital balance containing a custom weighted sample. At a constant temperature (190°C), the molten polymer strands are extruded from a standard plastic meter barrel using a weighted piston through a standard ASTM D1238 MFR die (orifice height [8.000 ± 0.025 mm] and diameter [2.0955 ± 0.005 mm]). In the D-MELT device, the extrudate is pulled onto a drum driven by a stepper motor through 2 free-rotating rollers, which are ramped up over a range of speeds during the analysis. The integrated control computer in the D-MELT device records the force of pulling the polymer strands upward on the tension roller mounted on the force sensor platform. According to the curve fitting function of the obtained force data, the final reported value is determined based on a constant speed ratio of the polymer strand speed to the die outlet speed (the exact speed ratio depends on the product group). Depending on the rheometer type, the measurements are reported as melt elasticity ("ME") in centinewtons (cN) or melt force ("MF") in millinewtons (mN).

[0031] Melt index

[0032] As used herein, the term "melt index" (or "MI") refers to a measure of how easily a thermoplastic polymer flows when in a molten state. Melt index or I2 is measured according to ASTM D 1238, Condition 190°C / 2.16 kg, and is reported in grams eluted per 10 minutes (g / 10 min). 10 Measured according to ASTM D1238, Condition 190°C / 10 kg, and reported in grams eluted per 10 minutes (g / 10 min).As used herein, the term "fractional melt index" refers to a melt index less than 1.0 g / 10 min.

[0033] Nuclear magnetic resonance (NMR) 1 H NMR)

[0034] As used herein, the term "nuclear magnetic resonance" or "NMR" refers to a spectroscopic analysis of a material or compound that shows the elemental and structural composition of a material or compound. Samples for proton NMR were prepared using 0.1-0.2 g of sample in 2.75 g of 30 / 70 wt / wt o-dichlorobenzene-d4 / perchloroethylene (ODCB-d4 / PCE) containing 0.001 M Cr prepared in a 10 mm tube. The sample was heated and vortexed at 115 ° C to ensure homogeneity. Single pulse proton spectra were obtained on a Bruker AVANCE 400 MHz spectrometer equipped with a Bruker Dual DUL high temperature cryoprobe and a sample temperature of 120 ° C. PBD spectra were obtained with ZG pulses P1 = 5 us (~30 ° PW), 16 scans, AQ 1.64 s, D1 14 s. The LDPE-PBD sample was run using a ZG pulse with 90° PW, 32 scans, AQ 1.64s, D114s.

[0035] Gel Permeation Chromatography (GPC)

[0036] The chromatographic system consists of a PolymerChar GPC-IR (Valencia, Spain) high temperature GPC chromatograph equipped with an internal IR5 infrared detector (IR5) and a 4-capillary viscometer (DV) connected to a Precision Detectors (now Agilent Technologies) 2-angle laser scattering (LS) detector model 2040. For all absolute light scattering measurements, a 15 degree angle was used for measurement. The autosampler oven chamber was set to 160°C, and the column chamber was set to 150°C. The columns used were 4 Agilent "MixedA" 30cm 20 micron linear mixed bed columns. The chromatographic solvent used was 1,2,4-trichlorobenzene and contained 200ppm of butylated hydroxytoluene (BHT). The solvent source was sparged with nitrogen. The injection volume used was 200 microliters, and the flow rate was 1.0 ml / min.

[0037] Calibration of the GPC column set was performed with at least 20 narrow molecular weight distribution polystyrene standards, the molecular weights of which ranged from 580 to 8,400,000 and were arranged in 6 "cocktail" mixtures, with at least ten times the interval between individual molecular weights. Standards were purchased from Agilent Technologies. Polystyrene standards were prepared in an amount of 0.025 grams in 50 ml of solvent for molecular weights equal to or greater than 1,000,000, and in an amount of 0.05 grams in 50 ml of solvent for molecular weights less than 1,000,000. Gently agitate at 80°C for 30 minutes to dissolve the polystyrene standards. The peak molecular weight of the polystyrene standards was converted to polyethylene molecular weight using Equation 1 (as described by Williams and Ward, J. Polym. Sci., Polym. Let., 6, 621 (1968)):

[0038] M 聚乙烯 =A×(M 聚苯乙烯 ) B (Equation 1)

[0039] Where M is the molecular weight, A has a value of 0.4315 and B equals 1.0.

[0040] A polynomial between the 3rd and 5th order was used to fit the corresponding polyethylene equivalent calibration points. A small adjustment was made to A (from about 0.375 to 0.440) to correct for column resolution and band broadening effects so that the homopolymer polyethylene standard had a molecular weight of 120,000.

[0041] Total plate counts for the GPC column set were performed using eicosane (prepared at 0.04 g in 50 mL TCB and dissolved for 20 minutes with gentle agitation). Plate counts (Equation 2) and symmetry (Equation 3) were measured with a 200 microliter injection according to the following equations:

[0042]

[0043] Where RV is the retention volume in milliliters, peak width is in milliliters, peak maximum is the maximum height of the peak, and 1 / 2 height is 1 / 2 the height of peak maximum.

[0044]

[0045] Where RV is the retention volume in milliliters and the peak width is in milliliters, peak maximum is the maximum position of the peak, tenth height is 1 / 10 the height of the peak maximum, and where post peak refers to the tail of the peak at a retention volume later than the peak maximum, and where front peak refers to the front of the peak at a retention volume earlier than the peak maximum. The plate count of the chromatographic system should be greater than 24,000 and the symmetry should be between 0.98 and 1.22.

[0046] The samples were prepared semi-automatically using the PolymerChar "Instrument Control" software, where the target weight of the sample was set to 2 mg / ml, and the solvent (containing 200 ppm BHT) was added to a septum-covered vial previously sparged with nitrogen by the PolymerChar high temperature autosampler. The samples were dissolved at 160 degrees Celsius for 2 hours under "slow" shaking.

[0047] Based on the GPC results, the internal IR5 detector (measurement channel) of the PolymerChar GPC-IR spectrometer was used, according to Equations 4-6, using the PolymerChar GPCOne TM The software was used to calculate the Mn of the baseline-subtracted IR chromatogram at each equidistant data collection point (i) and the polyethylene equivalent molecular weight obtained from the narrow standard calibration curve at point (i) according to Equation 1. (GPC) 、Mw (GPC) and Mz (GPC) Calculation.

[0048]

[0049]

[0050]

[0051] To monitor deviations over time, a flow rate marker (decane) was introduced into each sample via a micropump controlled using a PolymerChar GPC-IR system. This flow rate marker (FM) was used to linearly correct the pump flow rate (flow rate (nominal)) for each sample by comparing the RV of the corresponding decane peak in the sample (RV (FM sample)) with the RV of the alkane peak in the narrow standard calibration (RV (calibrated by FM)). It was then assumed that any changes in the decane marker peak time were related to linear changes in the flow rate (flow rate (effective)) throughout the run. In order to facilitate the highest accuracy measured for the RV of the flow marker peak, a least squares fitting procedure was used to fit the peak of the flow marker concentration chromatogram to a quadratic equation. The first derivative of the quadratic equation was then used to solve for the true peak position. After calibrating the system based on the flow marker peak, the effective flow rate (relative to the narrow standard calibration) was calculated as Equation 7. By PolymerCharGPCOne TM The software completes the processing of the flow marker peaks. An acceptable flow rate correction is such that the effective flow rate should be within + / - 2% of the nominal flow rate.

[0052] Flow rate (effective) = flow rate (nominal) * (RV (FM校准) / RV (FM样品) ) (Equation 7)

[0053] Triple Detector GPC (TDGPC)

[0054] The chromatography system, running conditions, column setup, column calibration and calculation of conventional molecular weight moments and distributions were performed according to the methods described in Gel Permeation Chromatography (GPC).

[0055] To determine the offset of the viscometer and light scattering detectors relative to the IR5 detector, a systematic method for determining the multi-detector offset was performed in a manner consistent with that published by Balke, Mourey et al. (Mourey and Balke, Chromatography Polym. Chapter 12, (1992)) (Balke, Thitiratsakul, Lew, Cheung, Mourey, Chromatography Polym. Chapter 13 (1992)) using the PolymerChar GPCOne TM The software optimizes the triple detector log (MW and IV) results from broad homopolymer polyethylene standards (Mw / Mn>3) with the narrow standards column calibration results from the narrow standards calibration curve.

[0056] Absolute molecular weight data were obtained using the PolymerChar GPC One in a manner consistent with that published by Zimm (Zimm, B.H., Journal of Chemical Physics, 16, 1099 (1948)) and Kratochvil (Kratochvil, P., Classical Light Scattering from Polymer Solutions, Elsevier, Oxford, New York (1987)). TM The total injected concentration used to determine the molecular weight is obtained from the mass detector area and the mass detector constant, which is derived from a suitable linear polyethylene homopolymer or one of the polyethylene standards of known weight average molecular weight. The calculated molecular weight (using GPCOne TM ) is obtained using the light scattering constants from one or more of the polyethylene standards mentioned below and a refractive index concentration coefficient dn / dc of 0.104. Typically, the mass detector response (IR5) and the light scattering constant (using GPCOne TM Viscometer calibration (using GPCOne TM The viscometer constants (measured using GPCOne TM The specific viscosity area (DV) and injected mass of the calibration standards are related to their intrinsic viscosity. The chromatographic concentrations are assumed to be low enough to eliminate the effect of the 2nd viral coefficient (the effect of concentration on molecular weight).

[0057] Absolute weight average molecular weight (MW (Abs) )Yes (Using GPCOne TM ) is obtained by dividing the area of ​​the light scattering (LS) integrated chromatogram (calculated from the light scattering constant) by the mass recovered from the mass constant and the mass detector (IR5) area. Molecular weight and intrinsic viscosity responses are at the end of the chromatogram where the signal-to-noise ratio becomes low (using GPCOne TM ) linear extrapolation. Other corresponding moments Mn (Abs) and Mz (Abs) The calculations based on equations 8 to 9 are as follows:

[0058]

[0059]

[0060] gpcBR Branching Index by Triple Detector GPC (3D-GPC)

[0061] The gpcBR branching index is determined by first calibrating the light scattering, viscosity and concentration detectors as described above. The baseline is then subtracted from the light scattering, viscometer and concentration chromatograms. The integration window is then set to ensure integration of all low molecular weight retention volume ranges in the light scattering and viscometer chromatograms, and the chromatogram indicates the presence of detectable polymer from the infrared (IR5) chromatogram. Linear polyethylene standards are then used to establish polyethylene and polystyrene Mark-Houwink constants. After obtaining the constants, the two values ​​are used to construct two linear reference conventional calibrations of polyethylene molecular weight and polyethylene intrinsic viscosity as a function of elution volume, as shown in equations (10) and (11):

[0062] M PE =(K PS / K PE ) 1 / α PE +1 ·M PS αPS+1 / αPE+1 (Equation 10)

[0063] [η] PE =K PS ·M PS α+1 / M PE (Equation 11)

[0064] The gpcBR branching index is a robust method for characterizing long chain branching, as described in Yau, Wallace W., Examples of Using 3D-GPC—TREF for Polyolefin Characterization, Macromol. Symp., 2007, 257, 29-45. The index avoids the "slice-by-slice" 3D-GPC calculations and branching frequency calculations traditionally used to determine g' values, in favor of the entire polymer detector area. From the 3D-GPC data, the peak area method can be used to obtain the sample bulk absolute weight average molecular weight (Mw, Abs) by a light scattering (LS) detector. This method avoids the "slice-by-slice" ratio of the light scattering detector signal to the concentration detector signal required in the traditional g' determination.

[0065] For 3D-GPC, the sample intrinsic viscosity is also obtained independently using equation (8). The area calculation in equations (5) and (8) provides higher accuracy because, as the total sample area, it is less sensitive to changes caused by detector noise and 3D-GPC settings on the baseline and integration limits. More importantly, the peak area calculation is not affected by detector volume offset. Similarly, the sample intrinsic viscosity (IV) is obtained with high accuracy by the area method shown in equation (12):

[0066]

[0067] where η spi Represents the specific viscosity obtained from the viscometer detector.

[0068] To determine the gpcBR branching index, the light scattering elution area of ​​the sample polymer is used to determine the molecular weight of the sample. The viscosity detector elution area of ​​the sample polymer is used to determine the intrinsic viscosity (IV or [η]) of the sample.

[0069] First, the molecular weight and intrinsic viscosity of a linear polyethylene standard (eg, SRM 1475a) or equivalent is determined using a conventional calibration ("cc") for both molecular weight and intrinsic viscosity as a function of elution volume.

[0070]

[0071] Equation (14) is used to determine the gpcBR branching index:

[0072]

[0073] where [η] is the measured intrinsic viscosity, [η] cc is the intrinsic viscosity from conventional calibration, Mw is the measured weight average molecular weight, and Mw ,cc is the conventionally calibrated weight average molecular weight. The weight average molecular weight by light scattering (LS) is often referred to as the "absolute weight average molecular weight" or "Mw,Abs". Mw,cc using a conventional GPC molecular weight calibration curve ("conventional calibration") is often referred to as the "polymer chain backbone molecular weight", "conventional weight average molecular weight" and "Mw, GPC ”.

[0074] All statistical values ​​with a "cc" subscript were determined using their respective elution volumes, corresponding conventional calibrations and concentrations (Ci) as described previously. Non-subscripted values ​​are based on measurements of mass detector, LALLS and viscometer areas. Iterative Adjustment K PEThe values ​​of α and Log K were adjusted until the gpcBR measurement for the linear reference sample was zero. For example, the final values ​​of α and Log K for gpcBR in this particular case were determined to be 0.725 and -3.391 for polyethylene and 0.722 and -3.993 for polystyrene, respectively. These polyethylene coefficients were then entered into Equation 13.

[0075] Once the K and α values ​​were determined using the procedure discussed previously, the procedure was repeated using the branched samples. Since the best "cc" calibration values ​​were applied, the final Mark-Houwink constants obtained from the linear reference were used to analyze the branched samples.

[0076] The interpretation of gpcBR is straightforward. For linear polymers, the gpcBR calculated from equation (14) will be close to zero because the values ​​measured by LS and viscometry will be close to conventional calibration standards. For branched polymers, gpcBR will be higher than zero, especially for high levels of long chain branching, because the measured polymer molecular weight will be higher than the calculated Mw,cc, and the calculated IVcc will be higher than the measured polymer IV. In effect, the gpcBR value represents the fractional IV change due to the molecular size shrinking effect as a result of polymer branching. A gpcBR value of 0.5 or 2.0 means that the molecular size shrinking effect on IV is 50% and 200%, respectively, relative to an equivalent linear polymer molecule.

[0077] For these specific examples, the advantage of using gpcBR over traditional "g' index" and branching frequency calculations is due to the higher accuracy of gpcBR. All parameters used in the gpcBR index determination are obtained with good accuracy and are not adversely affected by the low 3D-GPC detector response at high molecular weights from the concentration detector. Errors in the detector volume alignment also do not affect the accuracy of the gpcBR index determination. Fourier Transform Infrared Analysis

[0078] The amount of terminal olefins and internal olefins (double bonds or unsaturation) per 1000 carbons (or "1000C") was determined by Fourier transform infrared analysis ("FTIR"). Sample films (about 250 to 300 microns thick) for FTIR analysis were compression molded by pressing about 0.5 g of sample pellets in a Carver hydraulic press with heated platens set to 190° C. The levels of terminal olefins and internal olefins were measured following a procedure similar to that outlined in ASTM method D6248. DETAILED DESCRIPTION

[0079] The present disclosure provides an ethylene-based polymer composition. The ethylene-based polymer composition includes a polymerization product of a mixture of ethylene monomers and hydrocarbon molecules with three or more terminal olefin groups. The ethylene-based polymer has a melt index of 0.1 g / 10 min to 1.0 g / 10 min.

[0080] In an embodiment, the ethylene-based polymer composition is formed by a process involving high pressure (greater than 100 MPa) and free radical polymerization. A mixture of ethylene monomers and hydrocarbon molecules having three or more terminal olefin groups are reacted together to form an ethylene-based polymer composition. The polymerization process is discussed in detail below.

[0081] Hydrocarbon molecules

[0082] Ethylene-based polymer compositions are polymerization products of a mixture of ethylene and hydrocarbon molecules with three or more terminal olefin groups. Hydrocarbon molecules have only carbon atoms and hydrogen atoms and have three or more terminal olefin groups. As used herein, the term "hydrocarbon molecules comprising three or more terminal olefin groups" (or interchangeably referred to as "hydrocarbon molecules") refers to a chemical component of a polymer chain consisting of only carbon atoms and hydrogen atoms, the polymer chain being side-chain and having three or more ends, wherein olefin groups (i.e., carbon-carbon double bonds) are present at each end. As used herein, the term "mixture of hydrocarbon molecules" refers to two or more hydrocarbon molecules, wherein at least two molecules are different in structure, property and / or composition.

[0083] In an embodiment, the number of terminal olefin groups present in each of the hydrocarbon molecules is 3, or 5, or 7, or 8 to 17, or 18. In another embodiment, the number of terminal olefin groups present in each of the hydrocarbon molecules is 3 to 40, or 5 to 40, or 10 to 40, or 12 to 20. For example, a mixture of hydrocarbon molecules may include a first hydrocarbon molecule having three terminal olefin groups and a second hydrocarbon molecule having twelve terminal olefin groups.

[0084] In an embodiment, each of the hydrocarbon molecules in the mixture has structure I:

[0085] Structure I

[0086]

[0087] wherein n (the number of terminal olefin groups) is 3 to 160, and m (the number of internal olefin groups) is 0 to 50. In another embodiment, n is 3, or 5, or 10, or 20, or 30, or 40, and m is 0, or 10, or 20, or 40, or 50. In another embodiment, n is 3 to 160, or 5 to 100, or 9 to 40, and m is 0 to 30, or 1 to 20, or 1 to 10.

[0088] In one embodiment, the mixture of hydrocarbon molecules consists of two or more hydrocarbon molecules having structure I:

[0089] Structure I

[0090]

[0091] Where n is the number of terminal olefin groups, m is the number of internal olefin groups, the average n content is from 9 to 40, and the average m content is from 1 to 10. The "average n content" is calculated by dividing the number average molecular weight (Mn) by the weight average molecular weight (Mw) of the hydrocarbon molecules, and then multiplying by the fraction of terminal olefin groups. The "average m content" is calculated by dividing the number average molecular weight (Mn) by the weight average molecular weight (Mw) of the hydrocarbon molecules, and then multiplying by the fraction of internal olefin groups.

[0092] In one embodiment, Structure I has the following respective average n content and average m content (expressed as "n / m"): 9-40 / 1-10, or 12-38 / 2-8, or 13-37 / 2-6, or 15-35 / 2-6, or 19 / 3, or 33 / 5.

[0093] In one embodiment, the mixture of hydrocarbon molecules based on structure I has a molecular weight distribution of 1.2 to 20. In another embodiment, the mixture of hydrocarbon molecules based on structure I has a molecular weight distribution of 1.2, or 1.3, or 1.4 to 2, or 5 to 10 or 20. In another embodiment, the mixture of hydrocarbon molecules based on structure I has a molecular weight distribution of 1.2 to 20, or 1.3 to 10, or 1.3 to 5.

[0094] In an embodiment, each of the hydrocarbon molecules has structure II:

[0095] Structure II

[0096]

[0097] wherein n is 3 to 160, and m is 0 to 50; x is 0 to 50, and y is 0 to 50. In another embodiment, n is 3, or 5, or 10, or 20 to 30, or 40, or 50, m is 0, or 1 to 10, or 20; x is 0, or 1, or 5, or 10, or 20 to 30, or 40; and y is 0, or 1, or 10, or 20 to 30, or 40. In another embodiment, n is 3 to 160, or 5 to 100, or 9 to 50, or 9 to 40; m is 1 to 10, or 2 to 5; x is 0 to 50, or 1 to 20, or 1 to 10; and y is 0 to 50, or 1 to 20, or 1 to 10.

[0098] The hydrocarbon molecules of structure I and / or structure II are interchangeably referred to hereinafter as "branching agents".

[0099] Symbols in Structure I and Structure II represents a cis-alkyl group or a trans-alkyl group relative to a double bond.

[0100] In an embodiment, a mixture of hydrocarbon molecules having structure I and / or structure II with different molecular weights is used.

[0101] It is understood that the present ethylene-based polymer composition may include (i) only structure I, (ii) only structure II, or (iii) a combination of structure I and structure II. It is understood that as used herein, the term "ethylene-based polymer composition" refers to a polymer that is a reaction product of ethylene having structure I and / or structure II.

[0102] In an embodiment, the ethylene-based polymer composition comprises 95 wt%, or 96 wt%, or 97 wt%, or 98 wt% to 99 wt%, or 99.5 wt%, or 99.7 wt%, or 99.9 wt% of ethylene and a mixture of an amount of hydrocarbon molecules, or 5.0 wt%, or 4.0 wt%, or 3.0 wt%, or 2.0 wt% to 1.0 wt%, or 0.5 wt%, or 0.3 wt%, or 0.1 wt% of hydrocarbon molecules in polymerized form. The weight percentages are based on the total weight of the ethylene-based polymer composition. In another embodiment, the ethylene-based polymer composition includes 95.0 wt% to 99.9 wt%, or 96 wt% to 99.8 wt%, or 98 wt% to 99.8 wt% ethylene in polymerized form, and the mixture of hydrocarbon molecules is present in an amount of 5.0 wt% to 0.1 wt%, or 4.0 wt% to 0.2 wt%, or 2.0 wt% to 0.2 wt%.

[0103] The ethylene-based polymer composition has a density of 0.909 g / cc to 0.940 g / cc. In an embodiment, the ethylene-based polymer composition has a density of 0.909 g / cc, or 0.915 g / cc, or 0.920 g / cc to 0.930 g / cc, or 0.935 g / cc, or 0.940 g / cc. In another embodiment, the ethylene-based polymer composition has a density of 0.910 g / cc to 0.940 g / cc, or 0.915 g / cc to 0.935 g / cc, or 0.917 g / cc to 0.930 g / cc, or 0.917 g / cc to 0.926 g / cc.

[0104] In one embodiment, the ethylene-based polymer composition has a melt force index of 40 to 120 g*mN / 10 min. As used herein, the term "melt force index" or "MFI" is defined by the following equation (A):

[0105] Equation (A)

[0106] MFI = MI x MF, where

[0107] MI is 0.1 to 1.0 g / 10 min, MF is 170 to 340 mN

[0108] And the obtained MFI is 40 to 120 g*mN / 10min.

[0109] MFI shows a modified melt force value separate from melt index.In one embodiment, the ethylene-based polymer composition has a MI of 0.1 to 0.5 g / 10 min, a MF of 190 to 260 mN, and an MFI of 40 to 80 g*mN / 10 min (Equation (A)).

[0110] The ethylene-based polymer composition has a terminal olefin content of 0.05 / 1000 carbon, or 0.10 / 1000 carbon, or 0.15 / 1000 carbon, or 0.2 / 1000 carbon, or 0.24 / 1000 carbon to 0.25 / 1000 carbon, or 0.3 / 1000 carbon, or 0.5 / 1000 carbon, or 0.8 / 1000 carbon; the ethylene-based composition also has an internal olefin content of 0.08 / 1000 carbon, or 0.10 / 1000 carbon to 1.2 / 1000 carbon, or 0.15 / 1000 carbon, or 0.2 / 1000 carbon.

[0111] In one embodiment, the ethylene-based polymer composition has a terminal to internal olefin ratio of 1.0 to 5.0. In another embodiment, the ethylene-based polymer composition has a terminal to internal olefin ratio of 1.1 to 4.0, or 1.2 to 3.5, or 1.3 to 3.0, or 1.4 to 2.5.

[0112] In another embodiment, the ethylene-based polymer composition has a total olefin content of greater than 0.1, from 0.15 to 0.45, from 0.18 to 0.40, or from 0.19 to 3.7.

[0113] In one embodiment, the ethylene-based polymer composition has a hexane extract content of 1.0 wt% to 3.0 wt%, based on the weight of the ethylene-based polymer composition. In another embodiment, the ethylene-based polymer composition has a hexane extract content of 1.1 wt% to 2.5 wt%, or 1.2 wt% to 2.0 wt%, or 1.3 wt% to 1.9 wt%, or 1.4 wt% to 1.8 wt%, or 1.5 wt% to 2.0 wt%.

[0114] In another embodiment, the ethylene-based polymer composition has an Mw / Mn greater than 20.0, or from 21.0 to 30.0, or from 22.0 to 29.0, or from 23.0 to 29.

[0115] In one embodiment, the ethylene-based polymer has a gpcBr value of greater than 3.0 or from 3.05 to 3.40.

[0116] In an embodiment, the ethylene-based polymer composition has one, some, or all of the following properties:

[0117] (i) MI is from 0.1, or 0.2, or 0.3 to 0.4, or 0.5 g / 10 min; and / or

[0118] (ii) MF is from 190 or 210 to 220 or 240 mN; and / or

[0119] (iii) an MFI of 40, or 50 to 60, or 70 g*mN / 10min; and / or

[0120] (iv) a terminal olefin content of 0.08 / 1000 carbons, or 0.10 / 1000 carbons, or 0.15 / 1000 carbons to 0.2 / 1000 carbons, or 0.24 / 1000 carbons, or 0.26 / 1000 carbons; and / or

[0121] (v) an internal olefin content of 0.08 / 1000 carbons, or 0.10 / 1000 carbons to 0.12 / 1000 carbons; and / or

[0122] (vi) a terminal olefin to internal olefin ratio of 1.3 to 3.0, or 1.4 to 2.5; and / or

[0123] (vii) Mw / Mn of 22.0 to 29.0; and / or

[0124] (viii) a gpcBr value of 3.05 to 3.40; and / or

[0125] (ix) a density of 0.910 g / cc to 0.925 g / cc;

[0126] In an embodiment, the polymer composition based on ethylene includes a blend component. A blend component is a polymer that does not include a mixture of hydrocarbon molecules (i.e., does not include a branching agent with structure I or structure II). Non-limiting examples of suitable blend components include ethylene-based polymers, ethylene / α-olefin copolymers, ethylene / C3-C8α-olefin copolymers, ethylene / C4-C8α-olefin copolymers, and copolymers of ethylene and one or more of the following comonomers: acrylate, (meth) acrylic acid, (meth) acrylate, carbon monoxide, maleic anhydride, vinyl acetate, vinyl propionate, maleic acid monoesters, maleic acid diesters, vinyltrialkoxysilanes, vinyltrialkylsilanes, and any combination thereof.

[0127] In an embodiment, the blend component is an ethylene-based polymer that does not include a mixture of hydrocarbon molecules.

[0128] In an embodiment, the blend component is high density polyethylene (HDPE).

[0129] In an embodiment, the blend component is linear low density polyethylene (LLDPE).

[0130] In another embodiment, the blend component is an ethylene / α-olefin copolymer. In a further embodiment, the α-olefin of the blend component is a C3-C8 α-olefin, or a C4-C8 α-olefin.

[0131] The ethylene-based polymer composition comprises a combination of two or more embodiments as described herein.

[0132] The present disclosure also provides an article comprising at least one component formed from the ethylene-based polymer composition described herein or a combination of two or more embodiments.

[0133] In an embodiment, the article is a coating of a film.

[0134] In an embodiment, the article is a coating.

[0135] In an embodiment, the article is a film.

[0136] An article comprises a combination of two or more embodiments as described herein.

[0137] method

[0138] The present disclosure also provides a process for producing the present ethylene-based polymer composition. The method includes polymerizing ethylene monomer in the presence of a mixture of hydrocarbon molecules (Structure I and / or Structure II) in a reactor configuration that provides high pressure (greater than 100 MPa) free radical polymerization conditions. The reactor configuration is one or more tubular reactors and / or one or more autoclave reactors.

[0139] In order to produce highly branched ethylene-based polymer compositions, a high-pressure free radical initiated polymerization process is used. Two different high-pressure free radical initiated polymerization process types are known. In the first process type, a stirred autoclave reactor with one or more reaction zones is used. The autoclave reactor typically has several injection points for initiator or monomer feed or both. In the second process type, a jacketed tube is used as a reactor with one or more reaction zones. Suitable but non-limiting reactor lengths can be 100 meters to 3000 meters (m), or 1000 meters to 2000 meters. The beginning of the reaction zone of either type of reactor is typically defined by the side injection of the initiator, ethylene, chain transfer agent (or telomer), comonomer, and any combination thereof of the reaction. The high-pressure process can be carried out in an autoclave reactor or a tubular reactor with one or more reaction zones, or in a combination of an autoclave reactor and a tubular reactor each containing one or more reaction zones. In an embodiment, an initiator is injected before the reaction zone initiating free radical polymerization.

[0140] In one embodiment, the method includes polymerizing ethylene monomer in the presence of a mixture of hydrocarbon molecules (Structure I and / or Structure II), chain transfer agents (CTA) and free radical initiators in a tubular reactor under high pressure (greater than 100 MPa) polymerization conditions. The tubular reactor is a multi-zone tubular reactor with alternating positions for feeding fresh ethylene to control the ratio of ethylene to CTA, thereby controlling polymer properties. Fresh ethylene monomer is added simultaneously in multiple positions to achieve the desired ethylene monomer and chain transfer rate. The addition of fresh CTA addition points is carefully selected to control polymer properties. Fresh CTA is added simultaneously at multiple positions to achieve the desired ratio of CTA to ethylene monomer. Similarly, the addition point and amount of fresh hydrocarbon molecules (Structure I and / or Structure II) are controlled to control gel formation while maximizing the desired properties of increased melt strength and performance in target applications. Fresh hydrocarbon molecules (Structure I and / or Structure II) are added simultaneously to multiple positions to achieve the desired ratio of hydrocarbon molecules to ethylene monomer. The use of a mixture of hydrocarbon molecules to broaden the molecular weight distribution and increase the melt strength of the polymer places further demands on the distribution of the mixture of CTA and hydrocarbon molecules along the reactor system in order to achieve the desired changes in product properties while minimizing potential negative effects such as gel formation, reactor fouling, process instability. Non-limiting examples of suitable tubular polymerization reactors include tubular reactors and polymerization conditions as disclosed in WO2013059042 (A1) and WO2013078018 (A2), the entire contents of each reference being incorporated herein by reference.

[0141] Non-limiting examples of ethylene monomers for producing ethylene-based polymer compositions include purified ethylene obtained by removing polar components from a loop recycle stream or by using a reaction system configuration so that only fresh ethylene is used to prepare the ethylene-based polymer composition of the present invention. Other examples of ethylene monomers include ethylene monomers from a recycle loop, wherein the method includes a recycle loop to increase conversion efficiency.

[0142] One or more chain transfer agents (CTA) are added to the tubular reactor to control molecular weight. Non-limiting examples of suitable CTAs include propylene, isobutane, n-butane, 1-butene, methyl ethyl ketone, acetone, ethyl acetate, propionaldehyde, ISOPAR (ExxonMobil Chemical Co.) and isopropanol and combinations thereof. The amount of the CTA used in the method is 0.01 to 10 weight percent, or 0.01 to 5 weight percent, or 0.1 to 1.0 weight percent, or 0.1 to 0.5 weight percent, or 0.01 to 0.1 weight percent of the total reaction mixture.

[0143] In one embodiment, the CTA is propionaldehyde.

[0144] One or more free radical initiators are fed into the tubular reactor to produce the polymer composition based on ethylene. The limiting examples of suitable free radical initiators include organic peroxides, cyclic peroxides, diacyl peroxides, dialkyl peroxides, hydroperoxides, peroxycarbonates, peroxydicarbonates, peroxyesters, peroxyketals, tert-butyl peroxypivalate, di-tert-butyl peroxide, tert-butyl peroxyacetate and tert-butyl peroxy-2-hexanoate, and combinations thereof. In one embodiment, the free radical initiator includes at least one peroxide group incorporated in the ring structure. Non-limiting examples of free radical initiators having peroxide groups incorporated in a ring structure include TRIGONOX 301 (3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxynonane) and TRIGONOX 311 (3,3,5,7,7-pentamethyl-1,2,4-trioxepane) available from Akzo Nobel, and HMCH-4-AL (3,3,6,6,9,9-hexamethyl-1,2,4,5-tetraoxacyclononane) available from United Initiators. These organic peroxy initiators are used in amounts of 0.001 wt % to 0.2 wt % based on the weight of the polymerizable monomers.

[0145] In one embodiment, the free radical initiator is a combination of t-butyl peroxy-2-ethylhexanoate and di-t-butyl peroxide.

[0146] In one embodiment, the polymerization is carried out in a tubular reactor having multiple reactor zones (3 to 6 reactor zones). The maximum temperature of each reactor zone is 150° C. to 360° C., or 170° C. to 350° C., or 200° C. to 340° C. The pressure in each tubular reactor zone is typically 100 MPa to 380 MPa, 110 MPa to 340 MPa, or 110 MPa to 300 MPa. The hydrocarbon molecules (Structure I and / or Structure II) are fed directly to the reaction zone or directly to the feed zone of the reaction zone through a compression stage.

[0147] In one embodiment, hydrocarbon molecules (structure I and / or structure II) are added at the entrance of the reaction zone before or simultaneously with the addition of free radical initiator. In another embodiment, hydrocarbon molecules (structure I and / or structure II) are added before the addition of initiator to achieve good dispersion.

[0148] In one embodiment, hydrocarbon molecules (Structure I and / or Structure II) are fed only to reaction zone 1 .

[0149] In an embodiment, the ethylene fed to the first reaction zone is 10% to 100% of the total ethylene fed to the polymerization. In other embodiments, the ethylene fed to the first reaction zone is 20% to 80%, further 25% to 75%, further 30% to 70%, further 40% to 60% of the total ethylene fed to the polymerization.

[0150] In one embodiment, the tubular reactor has three reactor zones. The method includes maintaining the peak temperature of the first reactor at 290°C to 310°C and the pressure at 230MPa to 200MPa, maintaining the peak temperature of the second reactor at 290°C to 310°C and the pressure at 225MPa to 195MPa, and maintaining the peak temperature of the third reactor at 290°C to 310°C and the pressure at 220MPa to 190MPa. The method includes feeding CTA (propionaldehyde) and peroxy radical initiators (tert-butyl peroxy-2-ethylhexanoate and di-tert-butyl peroxide) to each of the three reactor zones to control the peak temperature in the reactor and the MI of the final product. Ethylene monomer, hydrocarbon molecules (structure I and / or structure II) are fed to the first reactor zone only at a ratio of 0.0016 to 0.0048kg hydrocarbon molecules to kg ethylene. The method comprises polymerizing ethylene monomers in the presence of a mixture of hydrocarbon molecules (Structure I and / or Structure II), a chain transfer agent (CTA) and a free radical initiator under the above polymerization conditions and forming an ethylene-based polymer composition having one, some or all of the following properties:

[0151] (i) MI is from 0.1, or 0.2, or 0.3 to 0.4, or 0.5 g / 10 min; and / or

[0152] (ii) MF is from 190 or 210 to 220 or 240 mN; and / or

[0153] (iii) an MFI of 40, or 50 to 60, or 70 g*mN / 10min; and / or

[0154] (iv) a terminal olefin content of 0.08 / 1000 carbons, or 0.10 / 1000 carbons, or 0.15 / 1000 carbons to 0.2 / 1000 carbons, or 0.24 / 1000 carbons, or 0.26 / 1000 carbons; and / or

[0155] (v) an internal olefin content of 0.08 / 1000 carbon, or 0.10 / 1000 carbon to 0.12 / 1000 carbon; and / or

[0156] (vi) a terminal olefin to internal olefin ratio of 1.3 to 3.0, or 1.4 to 2.5; and / or

[0157] (vii) Mw / Mn of 22.0 to 29.0; and / or

[0158] (viii) a gpcBr value of 3.05 to 3.40; and / or

[0159] (ix) a density of 0.910 g / cc to 0.925 g / cc;

[0160] In one embodiment, the method includes polymerizing ethylene monomers under the above polymerization conditions in the presence of a mixture of hydrocarbon molecules (structure I and / or structure II), one or more additional monomers, a chain transfer agent (CTA), and a free radical initiator. Non-limiting examples of additional monomers include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, and 4-methyl-1-pentene, acrylic acid esters, (meth)acrylic acid, (meth)acrylic acid esters, carbon monoxide, maleic anhydride, vinyl acetate, vinyl propionate, maleic acid monoesters, maleic acid diesters, vinyl trialkoxysilanes, vinyl trialkylsilanes, and any combination thereof.

[0161] additive

[0162] In an embodiment, the composition includes one or more additives. Non-limiting examples of additives include stabilizers, plasticizers, antistatic agents, pigments, dyes, nucleating agents, fillers, slip agents, flame retardants, processing aids, smoke suppressants, viscosity control agents, and antiblocking agents. Based on the weight of the ethylene-based polymer composition, the polymer composition may, for example, include less than 10% of the combined weight of one or more additives.

[0163] In an embodiment, the ethylene-based polymer composition is treated with one or more stabilizers, for example antioxidants, such as IRGANOX 1010, IRGANOX 1076, and IRGAFOS 168. Typically, the ethylene-based polymer composition is treated with one or more stabilizers prior to extrusion or other melt processing.

[0164] application

[0165] The ethylene-based polymer compositions of the present disclosure can be used in various conventional thermoplastic manufacturing processes to produce useful articles, including but not limited to single-layer and multilayer films; agricultural films, molded articles, such as blow-molded, injection-molded or rotationally-molded articles; coatings; fibers; and woven or nonwoven fabrics, cables, pipes, greenhouse films, silo bag films, collation shrink films, food packaging films, foams.

[0166] The ethylene-based polymer compositions can be used in a variety of films including, but not limited to, clear shrink films, agricultural films, collation shrink films, cast stretch films, silage films, stretch hoods, sealants, and diaper backsheets. Other suitable applications include, but are not limited to, wire and cable, gaskets and profiles, adhesives; footwear components, and automotive interior parts. The ethylene-based polymer compositions of the present invention can be used as part of a blend with LLDPE for agricultural films - large blown films.

[0167] Applicants have surprisingly discovered that using a mixture of hydrocarbon molecules in the reactor, wherein n is greater than three or n is greater than or equal to 5, results in an ethylene-based polymer composition having an increased number of branching points, thereby resulting in greater melt forces.

[0168] Examples

[0169] Polybutadiene (Additive A: Nisso PB B-1000, having structure I) was provided by Nippon Soda, Co. The properties of this material are listed in Table 1 below.

[0170] Table 1

[0171]

[0172] 1 Provided by Soda Co., Ltd.

[0173] 2 Determination by GPC

[0174] 3Calculated by dividing Mn by the Mw of butadiene monomer (hydrocarbon molecule) and multiplying by the fraction of terminal olefin groups of n and internal olefin groups of m. Example: Mn = 1200 g / mol, Avg n = (1200 g / mol) / (54.09 g / mol of butadiene monomer) = 22 repeat units * 0.85 (terminal / total olefins) = average 18.8 terminal vinyl groups / chain

[0175] Polymerization: Tubular Reactors

[0176] Comparison sample 1

[0177] Polymerization is carried out in a tubular reactor with three reaction zones. In each reaction zone, pressurized water is circulated through the jacket of the reactor, and the water is used to cool and / or heat the reaction medium. The inlet pressure is 222MPa, and the pressure drop of the whole tubular reactor system is about 30MPa. Each reaction zone has an inlet and an outlet. Each inlet stream is composed of the outlet stream from the previous reaction zone and / or the ethylene-rich feed stream added. Unconverted ethylene and other gaseous components in the reactor outlet are recycled by high pressure recycle and low pressure recycle, and compressed and distributed by a supercharger, a first stage and a super (secondary) compressor. Organic peroxides (peroxy-2-ethyl-tert-butyl hexanoate and di-tert-butyl peroxide) are fed into each reaction zone. Propionaldehyde (PA) is used as a chain transfer agent (CTA), and it is present in each reaction zone inlet, derived from low pressure and high pressure recycle streams. Only fresh PA is added to the second reaction zone and the third reaction zone at a ratio equal to 0.8 and 0.2 respectively. Fresh ethylene is directed to the first reaction zone.

[0178] After reaching the first peak temperature (maximum temperature) in reaction zone 1, the reaction medium is cooled by means of pressurized water. At the outlet of reaction zone 1, the reaction medium is further cooled by injecting a cold ethylene-rich feed, and the reaction is reinitiated by feeding an organic peroxide system. The process is repeated at the end of the second reaction zone to enable further polymerization in the third reaction zone. The polymer is extruded and pelletized (about 30 pellets / gram) at a melt temperature of about 230-250° C. using a single screw extruder. The weight ratio of the ethylene-rich feed stream to the three reaction zones is 1.00:0.80:0.20. The internal processing speeds of the first reaction zone, the second reaction zone, and the third reaction zone are about 12.5, 9, and 11 m / sec, respectively. Other information can be found in Tables 2 and 3.

[0179] Invention Example 1

[0180] The polymerization was carried out in a tubular reactor with three reaction zones, as discussed above for Comparative Sample 1. All process conditions were the same as Comparative Sample (CS) 1, except that in Inventive Example 1, Additive A was added to the first zone. Additional information can be found in Tables 2 and 3.

[0181] Invention Example 2

[0182] The polymerization was carried out in a tubular reactor with three reaction zones as discussed above for Inventive Example 1. All process conditions were the same as Inventive Example (IE) 1 except that additional additive A was fed to the first zone. Further information can be found in Tables 2 and 3.

[0183] Table 2: Pressure and temperature conditions of comparative examples and inventive examples

[0184]

[0185] Table 3: Polymer properties of examples

[0186]

[0187] It is particularly intended that the present disclosure is not limited to the embodiments and descriptions contained herein, but includes modifications of those embodiments including parts of the embodiments and combinations of elements of different embodiments as appear within the scope of the following claims.

Claims

1. An ethylene-based polymer composition formed by free radical polymerization of the following materials under high pressure greater than or equal to 100 MPa: Ethylene monomer, and A mixture of hydrocarbon molecules, each hydrocarbon molecule containing three or more terminal olefin groups, wherein the melt index MI of the ethylene-based polymer composition is 0.1 to 1.0 g / 10 min, The hydrocarbon molecule has structure I: Structure I wherein n is 9 to 40, and m is 1 to 10, The free radical polymerization is carried out in a tubular reactor having a plurality of reaction zones, and the mixture of hydrocarbon molecules is fed only to the first reaction zone.

2. The ethylene-based polymer composition of claim 1, wherein the ethylene-based polymer composition has a melt force MF of 170 to 340 mN.

3. The ethylene-based polymer composition of claim 1, wherein the ethylene-based polymer composition has a melt force index (MFI) defined by the following equation (A): Equation (A) MFI=MI*MF wherein MI is 0.1 to 1.0 g / 10 min, MF is 170 to 340 mN; and The MFI is 40 to 120 g*mN / 10 min.

4. The ethylene-based polymer composition according to any one of claims 1 to 3, wherein n is 12 to 35, and m is 2 to 8.

5. The ethylene-based polymer composition according to any one of claims 1 to 3, wherein n is 12 to 20 and m is 2 to 6; and / or The tubular reactor has 3 to 6 reaction zones.

6. The ethylene-based polymer composition of any one of claims 1-3, wherein the ethylene-based polymer composition comprises, in polymerized form, 95 wt% to 99.98 wt% of ethylene and 0.02 wt% to 5.0 wt% of a mixture of the hydrocarbon molecules, based on the total weight of the ethylene-based polymer composition.

7. The ethylene-based polymer composition of any one of claims 1 to 3, wherein the ethylene-based polymer composition has a terminal olefin content of 0.05 / 1000 carbons to 0.8 / 1000 carbons.

8. The ethylene-based polymer composition of any one of claims 1-3, wherein the ethylene-based polymer composition has an internal trans-olefin content of 0.07 / 1000 carbons to 0.2 / 1000 carbons.

9. The ethylene-based polymer composition of any one of claims 1-3, wherein the ethylene-based polymer composition has a density from 0.909 g / cc to 0.940 g / cc.

10. The ethylene-based polymer composition of any one of claims 1-3, further comprising a blend component, wherein the blend component does not include a mixture of the hydrocarbon molecules.

11. An article comprising the composition according to any one of claims 1 to 10.

12. The article of claim 11, wherein the article is selected from the group consisting of a film, a coating, and a coated sheet.

13. The article of claim 11, wherein the article is a coating for a cable.

14. The article of claim 11, wherein the article is a coating for an electrical wire.

15. A method comprising: reacting a mixture of ethylene monomer and hydrocarbon molecules, each hydrocarbon molecule comprising three or more terminal olefin groups, in a polymerization reactor under free radical polymerization conditions and at a pressure greater than or equal to 100 MPa; and forming an ethylene-based polymer composition having a melt index MI of 0.1 to 1 g / 10 min, The hydrocarbon molecule has structure I: Structure I wherein n is 9 to 40, and m is 1 to 10, The free radical polymerization is carried out in a tubular reactor having a plurality of reaction zones, and the mixture of hydrocarbon molecules is fed only to the first reaction zone.

16. The process according to claim 15, wherein the polymerization takes place in a reactor configuration comprising at least one tubular reactor.

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