Polymers of ethylene and monocyclic organosiloxanes

Abstract

The present invention discloses an ethylene-based polymer composition, which comprises units derived from ethylene, units derived from a comonomer, and optionally units derived from a terpolymer. The comonomer is a monocyclic organosiloxane (MOCOS) of the following formula (I): [R 1 , R 2 SiO 2 / 2 n where n is an integer greater than or equal to 3, and each R 1 is independently a (C2-C4) alkenyl or H2C═C(R 1a )-C(═O)-O-(CH2) m - where R la is H or methyl, m is an integer from 1 to 4, and each R 2 is independently H, a (C1-C4) alkyl, phenyl or R 1 .

Description

BACKGROUND OF THE INVENTION

[0001] The level of branching in ethylene-based polymers such as low density polyethylene (LDPE) is attributed, for example, mainly to the reactor design (autoclave or tubular) and the polymerization conditions used to prepare LDPE. Branching agents for increasing the level of branching in LDPE are known. However, the process conditions required to obtain modified LDPE with a high level of branching typically result in a final product with poor properties, including a higher content of low molecular weight extractable fractions.

[0002] Accordingly, there is a continuing recognized need for LDPE having increased melt strength relative to an increased level of branching, prepared under polymerization conditions that maintain good polymer properties. SUMMARY OF THE INVENTION

[0003] The present disclosure relates to an ethylene-based polymer composition. In one embodiment, the ethylene-based polymer composition comprises units derived from ethylene, units derived from a comonomer, and optionally units derived from a terpolymer. The comonomer is a monocyclic organosiloxane (MOCOS) of formula (I)

[0004] [R 1 , R 2 SiO 2 / 2 n

[0005] wherein n is an integer greater than or equal to 3,

[0006] each R 1 is independently a (C2-C4) alkenyl or H2C═C(R 1a )-C(═O)-O-(CH2) m -

[0007] wherein R 1a is H or methyl,

[0008] m is an integer from 1 to 4, and

[0009] each R 2 is independently H, (C1-C4) alkyl, phenyl, or R 1 .

[0010] Definition

[0011] Any reference to the Periodic Table of the Elements is to the Periodic Table of the Elements published by CRC Press, Inc. in 1990-1991. A group of elements in the table is referred to by the new notation for numbering the groups.

[0012] ​For purposes of U.S. patent practice, the content of any referenced patent, patent application, or publication is incorporated by reference in its entirety (or its equivalent U.S. version is incorporated by reference), particularly with respect to the disclosure of definitions (to the extent not inconsistent with any definitions specifically provided in this disclosure).

[0013] The numerical ranges disclosed herein include all values from the lower value to the upper value, and include the lower and upper values. For ranges containing definite values (e.g., 1 or 2, or 3 to 5, or 6, or 7), any sub-range between any two definite values is included (e.g., the above range 1 to 7 includes sub-ranges such as 1 to 2; 2 to 6; 5 to 7; 3 to 7; 5 to 6, etc.).

[0014] Unless stated to the contrary, implied by the context, or customary in the art, all parts and percentages are by weight, and all test methods are current methods as of the filing date of this disclosure.

[0015] As used herein, "acrylate" is a monomer containing the following structure (A):

[0016] Structure (A)

[0017]

[0018] wherein R1 is a hydroxyl group or a C1-C 18 alkoxy group, and R2 is H or CH3. Monomers based on acrylates include acrylates and methacrylates.

[0019] "Alkane" is a saturated hydrocarbon. "Alkyl" (or "alkyl group") is an alkane having a valence (usually monovalent).

[0020] "Olefin" is a hydrocarbon containing a carbon-carbon double bond. "Alkenyl" (or "alkenyl group") is an olefin having a valence (usually monovalent).

[0021] The term "allyl" (or "allyl group") is a monovalent unsaturated C3H5 hydrocarbon. In other words, an allyl group is propylene minus one hydrogen atom.

[0022] As used, the term "blend" or "polymer blend" refers to a mixture of two or more polymers. The blend can be miscible or can be immiscible (not phase-separating at the molecular level). The blend can be or can not be phase-separated. The 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. The blend can be affected by physically mixing two or more polymers at the macro level (e.g., melt blending resins or compounding) or at the micro level (e.g., forming simultaneously within the same reactor).

[0023] The term "composition" means a mixture of materials that comprises the composition, as well as reaction products and decomposition products formed from the materials of the composition.

[0024] The terms "comprising", "including", "having", and derivatives thereof are not intended to exclude the presence of any additional component, step, or procedure, whether or not specifically disclosed. For any doubt, unless stated to the contrary, all compositions claimed by using the term "comprising" may include any additional additive, adjuvant, or compound, whether in polymeric form or otherwise. In contrast, the term "consisting essentially of" excludes from the scope of any subsequent recitation any other component, step, or procedure (except those that are not essential to the operability) other than the components, steps, or procedures recited. The term "consisting of" excludes any component, step, or procedure not specifically recited or listed. Unless otherwise stated, the term "or" refers to the listed members individually as well as in any combination. The use of the singular includes the use of the plural and vice versa.

[0025] "Ethylene-based polymer" is a polymer containing more than 50 weight percent (wt%) of polymerized ethylene monomer (based on the total amount of polymerizable monomers) and optionally may contain at least one comonomer. Ethylene-based polymers include ethylene homopolymers and ethylene copolymers (meaning units derived from ethylene and one or more comonomers). The terms "ethylene-based polymer" and "polyethylene" are used interchangeably.

[0026] As used herein, the term "ethylene monomer" or "ethylene" refers to a chemical unit having two carbon atoms with a double bond therebetween, and each carbon is bonded to two hydrogen atoms, wherein the chemical unit polymerizes with other such chemical units to form an ethylene-based polymer composition.

[0027] "Hydrocarbon" is a compound containing only hydrogen atoms and carbon atoms. "Hydrocarbyl" (or "hydrocarbyl group") is a hydrocarbon having a valence (usually monovalent). Hydrocarbons can have a straight-chain structure, a cyclic structure, or a branched structure.

[0028] As used herein, the term "linear low density polyethylene" (or "LLDPE") refers to a linear ethylene / α-olefin copolymer containing a heterogeneous short-chain branching distribution, which contains units derived from ethylene and units derived from at least one C3-C 10 α-olefin or C4-C8 α-olefin comonomer. LLDPE is characterized by very little long-chain branching (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 TMLinear 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).

[0029] As used herein, the term "low density polyethylene" (or LDPE) refers to polyethylene having a density of 0.910 g / cc to less than 0.940 g / cc, or 0.918 g / cc to 0.930 g / cc and a broad molecular weight distribution (MWD) of long chain branches (i.e., "broad MWD" is 4.0 to 20.0).

[0030] "Olefin" is an unsaturated aliphatic hydrocarbon having a carbon-carbon double bond.

[0031] The term "phenyl" (or "phenyl group") is a C6H5 aromatic hydrocarbon ring having a valence (usually monovalent).

[0032] As used herein, the term "polymer" or "polymeric material" refers to a compound prepared by polymerizing monomers, whether of the same type or different types, which in polymeric form provides multiple and / or repeating "units" or "monomer units" that make up the polymer. 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 copolymers, block copolymers, etc. The terms "ethylene / α-olefin polymer" and "propylene / α-olefin polymer" denote copolymers prepared as described above by polymerizing ethylene or propylene and one or more additional polymerizable α-olefin monomers, respectively. It should be noted that although polymers are commonly referred to as "made of", "based on", "containing" a specified monomer or monomer type, etc., in this context, the term "monomer" should be understood to refer to the polymerized residue of the specified monomer rather than the unpolymerized material. Generally, the polymers herein are referred to based on the "units" that are the polymerized form of the corresponding monomers.

[0033] Test method

[0034] Density is measured according to ASTM D792 Method B. Results are reported in grams per cubic centimeter (g / cc).

[0035] Fourier transform infrared analysis ("FTIR")

[0036] The amounts of terminal and internal trans double bonds per 1000 carbons (or “1000C”) are determined by Fourier transform infrared analysis (“FTIR”). Sample films (thickness approximately 250 to 300 microns) for FTIR analysis are compression molded by pressing approximately 0.5 g of sample pellets in a Carver hydraulic press with a heated platen set at 190 °C. The amounts of terminal and internal olefins per 1000 carbons are measured according to a procedure similar to that outlined in ASTM method D6248. FTIR measures internal olefin bonds in the trans configuration; internal olefin bonds in the cis configuration are not detectable by FTIR.

[0037] Gel permeation chromatography (GPC)

[0038] 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) coupled to a Precision Detectors (now Agilent Technologies) 2-angle laser light scattering (LS) detector model 2040. For all absolute light scattering measurements, a 15-degree angle is used for measurement. The autosampler oven chamber is set at 160 degrees Celsius and the column chamber is set at 150 degrees Celsius. The columns used are 4 Agilent “Mixed A” 30 cm 20 micron linear mixed-bed columns. The chromatographic solvent used is 1,2,4-trichlorobenzene (CAS 120-82-1, HPLC grade, from Fisher Scientific) and contains 200 ppm of butylated hydroxytoluene (BHT). The solvent source is nitrogen sparged. The injection volume used is 200 microliters and the flow rate is 1.0 mL / min.

[0039] Calibration of the GPC column set is performed with at least 20 narrow molecular weight distribution polystyrene standards with molecular weight ranges from 580 to 8,400,000 and arranged in 6 “cocktail” mixtures with at least a ten-fold separation between each molecular weight. The standards are purchased from Agilent Technologies. For molecular weights equal to or greater than 1,000,000, 0.025 g of polystyrene standard is prepared in 50 mL of solvent, and for molecular weights less than 1,000,000, 0.05 g of polystyrene standard is prepared in 50 mL of solvent. The polystyrene standards are dissolved at 80 degrees Celsius and gently stirred for 30 minutes. The polystyrene standard peak molecular weights are converted to polyethylene molecular weights using Equation 1 (as described in Williams and Ward, Journal of Polymer Science, Polymer Letters (J. Polym. Sci., Polym. Let.), 6, 621 (1968)):

[0040] M 聚乙烯 = A × (M 聚笨乙烯 ) B (Equation 1)

[0041] where M is the molecular weight, A has a value of 0.4315, and B equals 1.0.

[0042] A polynomial between 3rd and 5th order is used to fit the corresponding polyethylene equivalent calibration points. A small adjustment to A (from approximately 0.375 to 0.440) is made to correct for column resolution and band broadening effects such that the homopolymer polyethylene standard has a molecular weight of 120,000.

[0043] Plate counting of the GPC column set is performed with eicosane (prepared at 0.04 g in 50 mL of TCB and dissolved with slow stirring for 20 minutes). Plate count (Equation 2) and symmetry (Equation 3) are measured with a 200 μL injection according to the following equations:

[0044]

[0045] where RV is the retention volume in mL, the peak width is in mL, the peak maximum is the maximum height of the peak, and 1 / 2 height is 1 / 2 the height of the peak maximum.

[0046]

[0047] where RV is the retention volume in milliliters, and the peak width is in milliliters, the peak maximum is the maximum position of the peak, the one-tenth height is 1 / 10 of the height of the peak maximum, and where the trailing peak refers to the peak tail with a retention volume later than the peak maximum, and where the leading peak refers to the peak front with 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.

[0048] Samples were prepared semi-automatically using PolymerChar’s “Instrument Control” software, where the target weight of the sample was set at 2 mg / ml, and the solvent (containing 200 ppm BHT) was added to a septum-capped vial pre-bubbled with nitrogen through a PolymerChar high-temperature autosampler. The sample was dissolved at 160 °C for 2 hours with shaking at “low speed”.

[0049] Based on the GPC results, using the internal IR5 detector (measurement channel) of the PolymerChar GPC-IR chromatograph, according to Equation 4-6, using PolymerChar GPCOne TM software, the Mn (GPC) , Mw (GPC) and Mz (GPC) were calculated from the baseline-subtracted IR chromatogram at each equidistant data collection point (i) and the polyethylene equivalent molecular weight obtained from the calibration curve of the narrow standards at point (i) according to Equation 1.

[0050]

[0051]

[0052]

[0053] To monitor the deviation over time, a flow rate marker (decane) is introduced into each sample via a micropump controlled by a PolymerChar GPC-IR system. This flow rate marker (FM) is used to linearly correct the pump flow rate (flow rate (nominal)) of each sample by comparing the RV (RV(FM sample)) of the corresponding decane peak within the sample to the RV (RV(calibrated with FM)) of the alkane peak within the narrow standard calibration. Then, any change in the decane marker peak time is assumed to be related to a linear change in the flow rate (flow rate (effective)) over the course of the run. To facilitate the highest accuracy in the RV measurement of the flow marker peak, a least squares fitting procedure is used to fit the peak of the flow marker concentration chromatogram to a quadratic equation. Then, the first derivative of the quadratic equation is used to solve for the true peak position. After calibrating the system based on the flow marker peak, the effective flow rate (relative to narrow standard calibration) is calculated according to Equation 7. The processing of the flow marker peak is completed by PolymerChar GPCOne TM software. An acceptable flow rate correction results in the effective flow rate being within + / - 2% of the nominal flow rate.

[0054] Flow rate (effective) = Flow rate (nominal) * (RV(calibrated with FM) / RV(FM sample)) (Equation 7)

[0055] Triple detector GPC (TDGPC)

[0056] The chromatographic system, run conditions, column settings, column calibration, and calculation of conventional molecular weight moments and distributions are performed according to the methods described in gel permeation chromatography (GPC).

[0057] To determine the offsets of the viscometer and light scattering detector relative to the IR5 detector, the systematic method for determining multi-detector offsets is 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)) in a manner consistent with that published, thus using PolymerChar GPCOne TM software to optimize the triple detector log (MW and IV) results from a broad homopolymer polyethylene standard (Mw / Mn > 3) with the narrow standard column calibration results from the narrow standard calibration curve.

[0058] Absolute molecular weight data uses PolymerChar GPCOne TMThe software was obtained in a manner consistent with the following publications: Zimm (Zimm, B.H., Journal of Physical Chemistry, 16, 1099 (1948)) and Kratochvil (Kratochvil, P., Classical Light Scattering from Polymer Solutions, Elsevier, Oxford, NY (1987)). The total injection concentration for determining the molecular weight was obtained based on the mass detector area and the mass detector constant, which was derived from one of the appropriate linear polyethylene homopolymers or polyethylene standards of known weight-average molecular weight. The calculated molecular weight (using GPCOne TM ) was obtained using the light scattering constant from one or more of the polyethylene standards mentioned below and the refractive index concentration coefficient dn / dc of 0.104. Generally, the mass detector response (IR5) and the light scattering constant (determined using GPCOne TM ) should be determined using linear standards with a molecular weight exceeding approximately 50,000 g / mol. Viscometer calibration (determined using GPCOne TM ) can be accomplished using the method described by the manufacturer or, alternatively, by using the published values (obtainable from the National Institute of Standards and Technology (NIST)) of a suitable linear standard such as Standard Reference Material (SRM) 1475a. The viscometer constant (obtained using GPCOne TM ) was calculated, which relates the specific viscosity area (DV) of the calibration standard and the injected mass to its intrinsic viscosity. It was assumed that the chromatographic concentration was low enough to eliminate the effect of resolving the second virial coefficient (the effect of concentration on molecular weight).

[0059] The absolute weight-average molecular weight (MW (Abs) ) was (using GPCOne TM ) obtained by dividing the area of the light scattering (LS) integrated chromatography (calculated from the light scattering constant) by the mass recovered from the mass constant and the mass detector (IR5) area. The molecular weight and intrinsic viscosity responses were linearly extrapolated at the chromatographic end where the signal-to-noise ratio became low (using GPCOne TM ). The other corresponding moments Mn (Abs) and Mz (Abs) were calculated according to Equations 8 - 9 as follows:

[0060]

[0061]

[0062] gpcBR Branching Index by Triple Detector GPC (3D-GPC)

[0063] The gpcBR branching index is determined by first calibrating the light scattering, viscosity, and concentration detectors as described above. Then, the baselines are subtracted from the light scattering, viscometer, and concentration chromatograms. Then, the integration windows are set to ensure the integration of all low molecular weight retention volume ranges in the light scattering and viscometer chromatograms, where the chromatograms indicate the presence of detectable polymers from the infrared (IR5) chromatogram. Then, the polyethylene and polystyrene Mark-Houwink constants are established using linear polyethylene standards. After obtaining the constants, these 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):

[0064] M PE =(K PS / K PE ) 1 / α PE +1 ·M PS αPS+1 / αPE+1 (Equation 10)

[0065] [η] PE =K PS ·M PS α+1 / M PE (Equation 11).

[0066] 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. This index avoids the "slice-by-slice" 3D-GPC calculations and branching frequency calculations traditionally used to determine g′ values, favoring the entire polymer detector region. From the 3D-GPC data, the absolute weight-average molecular weight of the sample bulk (Mw, Abs) can be obtained by the peak area method through the 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 traditional g′ determinations.

[0067] In the case of 3D-GPC, the sample intrinsic viscosity is also obtained independently using Equation (8). The area calculations in Equations (5) and (8) provide higher precision because, as the total sample area, it is less sensitive to variations 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 offsets. Similarly, a high-precision sample intrinsic viscosity (IV) is obtained by the area method shown in Equation (12):

[0068]

[0069] where η spi represents the specific viscosity obtained from the viscometer detector.

[0070] 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.

[0071] First, the molecular weight and intrinsic viscosity of a linear polyethylene standard sample (e.g., SRM1475a) or equivalent are determined for both the molecular weight and intrinsic viscosity varying with elution volume using conventional calibration (“cc”):

[0072]

[0073] Equation 14 is used to determine the gpcBR branching index

[0074]

[0075] 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 weight-average molecular weight of conventional calibration. The weight-average molecular weight determined by light scattering (LS) is usually referred to as the “absolute weight-average molecular weight” or “Mw,Abs”. Mw,cc using the conventional GPC molecular weight calibration curve (“conventional calibration”) is usually referred to as the “polymer chain backbone molecular weight”, “conventional weight-average molecular weight”, and “Mw, GPC ”.

[0076] All statistical values with the “cc” subscript are determined using their respective elution volumes and the corresponding conventional calibration and concentration (Ci) as described above. The non-subscript values are based on the measured values of the mass detector, LALLS, and viscometer area. Iteratively adjust K PEThe value is until the gpcBR measurement of the linear reference sample is zero. For example, in this specific case, the final values of α and Log K for gpcBR determination are 0.725 and -3.391 for polyethylene, and 0.722 and -3.993 for polystyrene, respectively. Then these polyethylene coefficients are input into Equation 13.

[0077] Once the K and α values are determined using the previously discussed procedure, repeat the procedure with the branched sample. Due to applying the optimal “cc” calibration value, the final Mark-Houwink constants obtained from the linear reference are used to analyze the branched sample.

[0078] The interpretation of gpcBR is straightforward. For linear polymers, the gpcBR calculated by Equation (14) will be close to zero because the values measured by LS and viscometry will be close to the 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 fact, the gpcBR value represents the fractional IV change due to the molecular size contraction effect as a result of polymer branching. A gpcBR value of 0.5 or 2.0 means that the molecular size contraction effect on IV is 50% and 200% respectively relative to the equivalent linear polymer molecules.

[0079] For these specific examples, the advantage of using gpcBR compared to the traditional “g′ index” and branching frequency calculations is due to the higher precision of gpcBR. All parameters used in the gpcBR index determination are obtained with good precision and are not adversely affected by the low 3D-GPC detector response at high molecular weights from the concentration detector. Errors in detector volume alignment also do not affect the precision of gpcBR index determination.

[0080] Melt strength

[0081] The melt force was measured using a D-MELT device (purchased from Goettfert GmbH Buchen, Germany). The D-MELT device includes a commercial plastometer and a digital balance combined with a customized weighted sample. At a constant temperature (190 °C), a molten polymer strand was extruded through a standard ASTM D1238 MFR die (orifice height [8.000 ± 0.025 mm] and diameter [2.0955 ± 0.005 mm]) using a weighted piston. In the D-MELT device, the extrudate was pulled onto a drum driven by a stepper motor through two freely rotating rollers, and the stepper motor was tilted within a speed range during the analysis. The force of the polymer strand pulled on the force sensor platform mounted on the tension roller was recorded by an integrated control computer in the D-MELT device. Based on the curve fitting function of the obtained force data, the final reported value was determined based on the constant speed ratio of the polymer strand speed to the die exit speed (the exact speed ratio depends on the product group). The measurement results are reported as melt elasticity ("ME") in centinewtons (cN) or melt force ("MF") in millinewtons (mN), depending on the rheometer type. Immediately after the force measurement, the melt index ("MI") was measured under ASTM conditions with the same charge.

[0082] Melt index

[0083] 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. The melt index or I2 is measured according to ASTM D 1238, Condition 190 °C / 2.16 kg and reported in grams eluted per 10 minutes (g / 10 min). I10 is measured according to ASTM D 1238, Condition 190 °C / 10 kg and reported in grams eluted per 10 minutes (g / 10 min).

[0084] Melt strength

[0085] As used herein, the term "melt strength" refers to a measure of the maximum tension applied to a polymer in a molten state before it breaks. The melt strength was measured at 190 °C using Rheotens 71.97 ( Inc.; Rock Hill, SC). Using a The Rheotester 2000 capillary rheometer feeds a molten sample (25 g to 50 g). The sample is fed into a barrel (L = 300 mm, diameter = 12 mm), compressed and melted for 10 minutes, and then extruded at a constant piston speed of 0.265 mm / s, which corresponds to 38.2 s at a given die diameter. -1 The extrudate passes through a wheel of the Rheotens located 100 mm below the die exit and is pulled downward by the wheel with an acceleration of 2.4 millimeters per square second (mm / s 2 ). The force applied to the wheel (measured in centinewtons (cN)) is recorded as a function of the speed of the wheel (mm / s). The sample is repeated at least twice until two curves of the force (in cN) as a function of the strand speed (in mm / s) overlap, and then the curve with the highest speed at strand breakage is reported. The melt strength (or "MS") is reported as the plateau force before strand breakage, in centinewtons, cN.

[0086] Nuclear magnetic resonance ( 1 H NMR)

[0087] As used herein, the terms "nuclear magnetic resonance" or "NMR" or "proton NMR" refer to the spectroscopic analysis of a material or compound that provides information about the chemical composition and structure of the material or compound. Samples for proton NMR are prepared using 0.1 g to 0.2 g of sample in 3.25 g of 30 / 70 wt / wt ortho-dichlorobenzene-d4 / perchloroethylene (ODCB-d4 / PCE) containing 0.001 M chromium(III) acetylacetonate Cr(AcAc)3, which is prepared in a 10 mm tube. The sample is heated and vortexed at 115 °C to ensure homogeneity. A single-pulse proton spectrum is obtained on a Bruker AVANCE 600 MHz spectrometer equipped with a Bruker high-temperature CryoProbe and a sample temperature of 120 °C. The spectrum is acquired using a ZG pulse P1 = 20 us (90° PW), 64 scans, AQ 1.82 s, D1 15 s.

[0088] By the 1 1H NMR spectrum obtained as described above, the amounts of Si-CH3 per 1000 carbons and Si-CH=CH2 (alternatively referred to as "Si-vinyl") groups per 1000 carbons are determined. The total polymeric protons are quantified by integration from approximately -0.5 ppm to 3 ppm, and this integration is set to a value of 2000 and thus represents 1000 carbons. The signal from three Si-vinyl protons appears as three separate multiplets from approximately 5.8 ppm to 6.1 ppm. The (D Vi)4 The multiplet overlaps partially with one of the vinyl protons at the chain end of LDPE at about 5.76 ppm. Therefore, only the two multiplets at about 5.92 ppm and 6.02 ppm are integrated and averaged to give the molar number of Si-vinyl per 1000 carbons. Description of the Drawings

[0089] Figure 1 is a graph showing the melt force (MF) against the weight percentage of MOCOS present in the resonance peak ethylene / MOCOS copolymer according to an embodiment of the present disclosure. Detailed Description

[0090] The present disclosure relates to ethylene-based polymer compositions. In one embodiment, the ethylene-based polymer composition comprises units derived from ethylene, units derived from a comonomer, and optionally units derived from a terpolymer. The comonomer is a monocyclic organosiloxane (MOCOS) of the following formula (I)

[0091] [R 1 , R 2 SiO 2 / 2 n

[0092] where n is an integer greater than or equal to 3,

[0093] each R 1 is independently a (C2-C4) alkenyl or H2C═C(R 1a )-C(═O)-O-(CH2) m-

[0094] where R 1a is H or methyl,

[0095] m is an integer from 1 to 4, and

[0096] each R 2 is independently H, (C1-C4) alkyl, phenyl or R 1 .

[0097] ​The ethylene-based polymer composition comprises (i) units derived from ethylene, (ii) units derived from a comonomer (hereinafter interchangeably referred to as “ethylene / MOCOS copolymer”), and (iii) optionally units derived from a terpolymer (hereinafter interchangeably referred to as “ethylene / MOCOS / terpolymer”), wherein the ethylene units constitute the major amount (weight %) of the monomers present in the polymer. In other words, the ethylene-based polymer composition comprises ethylene monomer, MOCOS comonomer (and optionally terpolymer), and each of these two monomers (or each of these three monomers when a terpolymer is present) is polymerized into the polymer backbone. In this way, the ethylene-based polymer of the present invention is structurally different from polyethylene having a functional additive grafted to the polymer chain in the form of a side chain.

[0098] In addition to ethylene, the ethylene-based polymer composition further comprises units derived from a comonomer. The comonomer is a monocyclic organosiloxane of formula (I) [R 1 , R 2 SiO 2 / 2 n , which is interchangeably referred to as “MOCOS” or “MOCOS comonomer”. Formula (I) is a molecule containing a monocyclic substructure composed of silicon and oxygen atoms arranged in an alternating pattern; and formula (I) contains an unsaturated organic (hydrocarbyl) group; and optionally hydrogen (“H”), a saturated substituent group or an aromatic substituent group. There are at least two unsaturated organic groups, and each of at least two silicon atoms in the cyclic substructure has at least one unsaturated organic group bonded thereto, and wherein after considering the unsaturated organic group and the oxygen atom, any remaining valence of the silicon atom is bonded to a hydrogen atom, a saturated substituent group or an aromatic substituent group; or a collection of such molecules.

[0099] MOCOS can be a monocyclic organosiloxane composed of a 6-membered ring (n = 3), an 8-membered ring (n = 4), a 10-membered ring (n = -5) or a 12-membered ring (n = 6). The cyclic substructure is composed of units of formula (I):

[0100] [R 1 , R 2 SiO 2 / 2 n ,

[0101] wherein n is an integer greater than or equal to 3, or n is 3, or 4 to 5, or 6,

[0102] each R 1 is independently a (C2-C4) alkenyl or H2C═C(R 1a )-C(═O)-O-(CH2) m- , wherein R​​1a is H or methyl,

[0103] each R 2 is independently H, (C1-C4)alkyl, phenyl or R 1 (as defined above). In each [R 1 ,R 2 SiO 2 / 2 unit, the R 1 group and the R 2 group are bonded to their respective silicon atoms. These units can be simply named D R1，R2 using the conventional siloxane shorthand notation, such that formula (I) becomes [D R1，R2 n 。R 1 and R 2 can be the same or different.

[0104] Non-limiting examples of compounds suitable for the MOCOS of formula (I) include: for the MOCOS shorthand name D Vi，Et ,R 1 is vinyl and R 2 is ethyl, where Vi is vinyl and Et is ethyl; for the MOCOS shorthand name D 烯丙基，Et ,R 1 is allyl and R 2 is ethyl; for the MOCOS shorthand name D 丁烯基，Et ,R 1 is butenyl (H2C=C(H)CH2CH2-) and R 2 is ethyl; for the MOCOS shorthand name D Vi，Vi ,R 1 is vinyl and R 2 is vinyl; for the MOCOS shorthand name D 烯丙基，烯丙基 ,R 1 is allyl and R 2 is allyl; for the MOCOS shorthand name D 丁烯基，丁烯基 ,R 1 is butenyl (H2C=C(H)CH2CH2-) and R 2 is butenyl; for the MOCOS shorthand name D Vi，Ph ,R1 is vinyl and R 2 is phenyl; for the MOCOS shorthand name D 烯丙基，Ph ,R 1 is allyl and R 2 is benzene; for the MOCOS shorthand name D 丁烯基，Ph ,R 1 is butenyl (H2C=C(H)CH2CH2-) and R 2 ​is phenyl.

[0105] When R 2 is methyl (CH3), this unit can be more simply named D R1 , such that formula (I) becomes [D R1 n . Further non - limiting examples of compounds of MOCOS applicable to formula (I) include: for the MOCOS shorthand name D Vi , R 1 is vinyl and R 2 is methyl; for the MOCOS shorthand name D 烯丙基 , R 1 is allyl and R 2 is methyl; for the MOCOS shorthand name D 丁烯基 , R 1 is butenyl (H2C=C(H)CH2CH2 -) and R 2 is methyl.

[0106] In one embodiment, for the MOCOS of formula (I), each R 1 is independently H2C=C(R 1a ) - C(=O) - O - (CH2) m -, where R 1a is H or methyl, and the subscript m is an integer from 1 or 2 to 3 or to 4 and any range or individual value therein. In a further embodiment, each R 2 is independently (C1 - C2) alkyl or (C2 - C3) alkenyl; or each R 2 is independently (C1 - C2) alkyl; or each R 2 is independently methyl.

[0107] In one embodiment, the MOCOS of formula (I) is 2,4,6 - trimethyl - 2,4,6 - trivinyl - cyclotrisiloxane “(D Vi )3” (CAS No. 3901 - 77 - 7) having the following structure (B):

[0108] Structure (B)

[0109]

[0110] In one embodiment, the MOCOS of formula (I) is 2,4,6,8 - tetramethyl - 2,4,6,8 - tetravinyl - cyclotetrasiloxane “(D Vi )4” (CAS No. 2554 - 06 - 5) having the following structure (C):

[0111] Structure (C)

[0112] ​

[0113] In one embodiment, the MOCOS of formula (I) is 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinyl-cyclopentasiloxane (D Vi )5.

[0114] The MOCOS comonomer of formula (I) is present in the ethylene-based polymer in an amount of 0.01 wt% to 2 wt%, or 0.01 wt% to 0.5 wt%, or 0.05 wt% to 0.45 wt%, or 0.1 wt% to 0.40 wt%, or 0.15 wt% to 0.30 wt%, or 0.05 wt% to 0.15 wt%. The weight percentages are based on the total weight of the ethylene-based polymer composition.

[0115] In addition to ethylene and the MOCOS comonomer, the ethylene-based polymer composition further comprises optional units derived from a terpolymer monomer. When present, the terpolymer monomer is an olefin, an unsaturated ester, a functionalized olefin, a silane, and combinations thereof. Non-limiting examples of suitable terpolymer monomers (when the terpolymer monomer is present) include propylene, C4-C8 α-olefins, acrylates, (meth)acrylates, vinyl acetate, vinyltrimethoxysilane, and combinations thereof. When the terpolymer monomer is present in the ethylene-based polymer, the terpolymer monomer is present in an amount of 0.5 wt% to 20 wt%, or 1 wt% to 15 wt%, or 3 wt% to 12 wt%, or 5 wt% to 10 wt%. The weight percentages are based on the total weight of the ethylene-based polymer composition.

[0116] In one embodiment, the ethylene-based polymer composition of the present invention comprises an ethylene / MOCOS copolymer of formula (I) and further comprises a terpolymer monomer of formula (II)

[0117] Formula (II)

[0118] [R 1 , R 2 SiO 2 / 2 n

[0119] wherein n is an integer greater than or equal to 3,

[0120] each R 1 is independently a methyl group, a (C2-C4) alkenyl group or H2C═C(R 1a )-C(═O)-O-(CH2) m -, provided that at least two R 1 are not methyl groups,

[0121] where R​1a is H or methyl,

[0122] m is an integer from 1 to 4, and

[0123] each R 2 is independently H, (C1-C4)alkyl, phenyl or R 1 .

[0124] The ethylene-based polymer composition may comprise one or more optional additives. When additives are present, non-limiting examples of suitable additives include stabilizers, light stabilizers, UV absorbers, antioxidants, plasticizers, antistatic agents, pigments, dyes, nucleating agents, fillers, slip agents, flame retardants, processing aids, smoke inhibitors, peroxides, crosslinking aids and scorch inhibitors, viscosity control agents and anti-caking agents. Based on the weight of the ethylene-based polymer composition, the ethylene-based polymer composition may for example comprise less than 10% by combined weight of one or more additives.

[0125] In one embodiment, the ethylene-based polymer composition is treated with one or more stabilizers, such as antioxidants, such as IRGANOX 1010, IRGANOX 1076 and IRGAFOS 168. Generally, the ethylene-based polymer composition is treated with one or more stabilizers prior to extrusion or other melt processes.

[0126] In one embodiment, the ethylene-based polymer composition is an ethylene / MOCOS copolymer composed of (i) ethylene and (ii) 0.05 wt% to 0.5 wt% of a MOCOS copolymer selected from (D Vi )3, (D Vi )4 and (D Vi )5, the ethylene / MOCOS copolymer having an Mw / Mn of 7.5 to 9.5, a vinyl content of 0.3600 / 1000 carbon atoms to 0.6200 / 1000 carbon atoms, a trans content of 0.1000 / 1000 carbon atoms to 0.3100 / 1000 carbon atoms, an MI of 2.0 g / 10 min to 5.0 g / 10 min and a melt strength of 5.0 cN to 8.5 cN.

[0127] In one embodiment, the ethylene-based polymer composition is an ethylene / MOCOS copolymer composed of (i) ethylene and (ii) 0.05 wt% to 0.5 wt% of (D Vi )4, the ethylene / MOCOS copolymer composition having one, some or all of the following properties:

[0128] (i) an Mw / Mn of 7.5 to 9.5; and / or

[0129] (ii) Vinyl content of 0.3600 / 1000 to 0.6200 / 1000 carbon atoms; and / or

[0130] (iii) Trans content of 0.1000 / 1000 to 0.3100 / 1000 carbon atoms; and / or

[0131] (iv) MI of 2.0 g / 10 min to 5.0 g / 10 min, or 2.5 g / 10 min to 4.7 g / 10 min; and / or

[0132] (v) Melt elasticity of 2.5 cN to 5.0 cN, or 2.7 cN to 4.8 cN; and / or

[0133] (vi) Melt force of 20 mN to 40 mN, or 22 mN to 37 mN; and / or

[0134] (vii) Melt strength of 5.0 cN to 8.5 cN, or 5.5 cN to 8.5 cN.

[0135] In one embodiment, the ethylene-based polymer composition is an ethylene / MOCOS copolymer composed of (i) ethylene and (ii) 0.1 wt% to 0.5 wt% of a MOCOS copolymer selected from (D Vi ) 4, the ethylene / MOCOS copolymer having an Mw / Mn of 7.0 to 7.5, a vinyl content of 0.5800 / 1000 to 0.6200 / 1000 carbon atoms, a trans content of 0.2000 / 1000 to 0.2500 / 1000 carbon atoms, and an MI of 35.0 g / 10 min to 42.0 g / 10 min.

[0136] In one embodiment, the ethylene-based polymer composition is an ethylene / MOCOS / MA terpolymer composed of (i) ethylene, (ii) 0.1 wt% to 0.5 wt% of MOCOS, and (iii) 8 wt% to 12 wt% of MA.

[0137] Application

[0138] The ethylene-based polymer compositions of the present disclosure can be used in a variety of conventional thermoplastic manufacturing processes to prepare useful articles, including but not limited to monolayer and multilayer films; agricultural films, molded articles such as blow molded articles, injection molded articles, or calender molded articles; coatings; fibers; and woven or non-woven fabrics, cables, tubes, greenhouse films, silo bag films, shrink wrap films, food packaging films, foams. The ethylene-based polymer compositions of the present invention are well-suited for applications that require crosslinking by free radical methods, such as organic peroxides, and such applications include but are not limited to insulation for power cables.

[0139] The ethylene-based polymer composition of the present invention can be used in a variety of films, including but not limited to transparent shrink films, agricultural films, finishing shrink films, cast stretch films, silage films, stretch hoods, sealants, and diaper backsheets. Other suitable applications include but are not limited to wire insulation, cable insulation, gaskets and profiles, adhesives; footwear components and automotive interior components. The ethylene-based polymer composition of the present invention can be used as part of a blend with LLDPE for agricultural films - large blown films.

[0140] By way of example and not limitation, some embodiments of the present disclosure will now be described in detail in the following examples.

[0141] Example

[0142] The materials used in the examples are listed in Table 1 below.

[0143] Table 1

[0144]

[0145]

[0146] The amounts of each material used in the examples of the present invention and comparative samples (controls) are provided in Table 2 below. A mixture of ethylene, MOCOS ((D Vi )4), propylene (as a chain transfer agent), and methyl acrylate (as a terpolymer monomer in Comparative Sample 6 and Examples 7 - 8 of the present invention) was added to a 545 milliliter (ml) stirred autoclave. An organic peroxide (Luperox 26) was added to the mixture as a 0.5 wt%, 1 wt%, or 2 wt% odorless solvent oil solution as a polymerization initiator, and the mixture was subjected to a set pressure of approximately 28,000 psi (1,969 kg / cm 2 ). The reactor temperature was set to a target temperature of 220 °C. Under the polymerization conditions shown in Table 2, ethylene / MOCOS copolymers were continuously synthesized and subsequently converted into pellet form by melt extrusion. The conditions listed in Table 2 are the average values over the time span during which the samples were collected. The "autoclave-prepared" experimental reactor copolymers thus formed were found to have the properties shown in Table 3.

[0147] Table 2: Polymerization conditions

[0148]

[0149]

[0150] Control = Comparative Sample

[0151] IE = Embodiment of the present invention

[0152] The characteristics of the obtained ethylene / MOCOS copolymer and ethylene / MOCOS / MA terpolymer are provided in Table 3 below.

[0153] Table 3 - Characteristics of ethylene / MOCOS copolymers and ethylene / MOCOS / MA terpolymers

[0154]

[0155] Control = Comparative sample

[0156] IE = Embodiment of the present invention

[0157] MA = Methyl acrylate, ME = Melt elasticity (cN), MF = Melt force (mN), MI = Melt index (g / 10 min), MS = Melt strength (cN)

[0158] NM = Not measured

[0159] * - wt% (D Vi )4 and wt% MA, based on the total weight of the ethylene-based polymer composition

[0160] + Vinyl and trans in mol%

[0161] Table 4: GPC characteristics of ethylene / MOCOS copolymers

[0162]

[0163] *ID = Identification, wt% (D in closed brackets Vj )4 is the first value and MI is the second value

[0164] Proton NMR is used to characterize the degree of incorporation / transformation of (D Vi )4 in the selected samples. Proton NMR detects the presence of Si—CH3 and Si-vinyl. On average, 2.5 double bonds per molecule of (D Vi )4 are incorporated into the polyethylene backbone (Table 5). Without being bound by a particular theory, it is believed that (D Vi )4 copolymerizes with ethylene and the incorporation of two double bonds produces an H-branched structure, thus unexpectedly increasing the melt strength.

[0165] Table 5 - NMR data of ethylene / MOCOS copolymers

[0166]

[0167] Figure 1Shows the melt forces of Control 1, IE11, IE2, IE3, and IE4 from Table 3 against weight percentage (D Vi )4 (from left to right). As Figure 1 shown, compared to the melt force of the comparative sample LDPE and Control 1, even low levels (from 0.5 wt% IE4 down to 0.08 wt% IE11) of (D Vi )4 result in a significant increase in the melt force. Figure 1 The linear regression lines of the examples of the present invention in 2 show a very good linear fit between the examples of the present invention (correlation coefficient R Vi is 0.9989), while the y-intercept of the linear regression line (19.4 mN) (which is much higher than that of the comparative example (12.8 mN)) indicates a highly non-linear behavior at very low levels of (D Vi )4. That is, even very low levels of (D Vi )4 result in a surprisingly rapid increase in the melt force; see, for example, IE11 at 0.08 wt% (D Vi )4 with the corresponding MF of 22.07 mN and IE2 at 0.15 wt% (D Vi )4 with the corresponding MF of 25.03 mN. At these low levels, the degree of effectiveness of (D Vi )4 in increasing the melt force is an unexpected result.

[0168] In particular, it is desirable that the present disclosure is not limited to the embodiments and descriptions contained herein, but includes modifications of those embodiments, which modifications include combinations of parts of the embodiments and elements of different embodiments that fall within the scope of the following claims.

Claims

1. An ethylene-based polymer composition, the ethylene-based polymer composition comprising: a polymer comprising: (i) greater than 50 wt% of units derived from ethylene, (ii) 0.01 to 2 wt% of units derived from a comonomer, and (iii) optionally 0 wt% to 20 wt% of units derived from an acrylate terpolymer monomer, wherein the weight percentages are based on the total weight of the polymer; and the comonomer is a monocyclic organosiloxane (MOCOS) of formula (I) [R 1 ,R 2 SiO 2 / 2 n ​ where n is an integer greater than or equal to 3, Each R 1 is independently a (C2-C4) alkenyl or H2C=C(R 1a )-C(=O)-O-(CH2) m - wherein R 1a is H or methyl; m is an integer from 1 to 4; and Each R 2 is independently H, (C1-C4)alkyl, phenyl or R 1 .

2. The ethylene-based polymer composition according to claim 1, the ethylene-based polymer composition comprising 0.01 wt% to 0.5 wt% of the MOCOS comonomer.

3. The ethylene-based polymer composition according to any one of claims 1 to 2, wherein the MOCOS comonomer is selected from the group consisting of: 2,4,6-trimethyl-2,4,6-trivinyl-cyclotrisiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane, 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinyl-cyclopentasiloxane, and combinations thereof.

4. The ethylene-based polymer composition according to any one of claims 1 to 2, wherein the ethylene-based polymer is an ethylene / MOCOS copolymer having (i) an Mw / Mn of 7.5 to 9.5, (ii) a vinyl content of 0.3600 / 1000 carbons to 0.6200 / 1000 carbons, and (iii) a trans content of 0.1000 / 1000 carbon atoms to 0.3100 / 1000 carbon atoms.

5. The ethylene-based polymer composition according to any one of claims 1 to 2, wherein the ethylene / MOCOS copolymer has (iv) an MI of 2.0 g / 10 min to 5.0 g / 10 min, and (v) a melt strength of 5.0 cN to 8.5 cN.

6. The ethylene-based polymer composition according to claim 1, wherein the terpolymer monomer is present.

7. The ethylene-based polymer composition according to claim 6, wherein the ethylene-based polymer comprises 0.01 wt% to 0.5 wt% of the MOCOS comonomer; and 0.5 wt% to 20 wt% of the terpolymer monomer.

8. An article, the article comprising the ethylene-based polymer composition according to any one of claims 1 to 7.

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