Belt for artificial turf

Abstract

The present disclosure provides a filament. In one embodiment, the filaments consist of a polyethylene composition. The polyethylene composition comprises (a) from 15% to 25% by weight of a first polyethylene component having a molecular weight (Mw) of greater than 200,000 g / mol and a density of from 0.925 g / cc to 0.945 g / cc, (b) from 20% to 35% by weight of a second polyethylene component having a molecular weight (Mw) of less than 80,000 g / mol and a density of from 0.915 g / cc to 0.950 g / cc, and (c) from 40% to 65% by weight of a third polyethylene component having a molecular weight (Mw) of less than 80,000 g / mol and a density of from 0.925 g / cc to 0.945 g / cc, the third polyethylene component has a molecular weight (Mw) of less than 100,000 g / mol and a density of from 0.940 g / cc to 0.965 g / cc. The polyethylene composition has a density of from 0.935 g / cc to 0.958 g / cc and a melt index (h) of from 0.5 g / 10 min to 5.0 g / 10 min. The present disclosure also provides a backing layer for artificial turf. The backing layer is prepared from filaments composed of a polyethylene composition.

Description

Background Technology

[0001] Conventional artificial turf consists of different materials: (i) polyethylene in yarn, (ii) polypropylene or polyester in the primary backing layer, and (iii) latex, polyurethane, or polyolefin dispersions in the secondary backing layer. Recyclability is becoming a key driver in the artificial turf industry. Several materials in conventional artificial turf are non-recyclable, such as polyester, latex, and polyurethane. In efforts to improve recyclability, high-density polyethylene (HDPE) has been proposed as an alternative material for the primary backing layer in artificial turf. Unfortunately, conventional HDPE detrimentally reduces the elongation of the primary backing layer and increases shrinkage.

[0002] There is a need for a recyclable artificial turf. Further, there is a need for an all-polyethylene (“monomaterial”) artificial turf that meets or exceeds the performance parameters of conventional artificial turf – durability, toughness, elongation, and low shrinkage. Summary of the Invention

[0003] This disclosure provides a filament. In one embodiment, the filament is composed of a polyethylene composition. The polyethylene composition comprises: (a) 15% to 25% by weight of a first polyethylene component having a molecular weight (Mw) greater than 200,000 g / mol and a density of 0.925 g / cc to 0.945 g / cc; (b) 20% to 35% by weight of a second polyethylene component having a molecular weight (Mw) less than 80,000 g / mol and a density of 0.915 g / cc to 0.950 g / cc; and (c) 40% to 65% by weight of a third polyethylene component having a molecular weight (Mw) less than 100,000 g / mol and a density of 0.940 g / cc to 0.965 g / cc. The polyethylene composition has a density of 0.935 g / cc to 0.958 g / cc and a melt index (I2) of 0.5 g / 10 min to 5.0 g / 10 min. This disclosure also provides a backing layer for artificial turf. The backing layer is prepared from filaments composed of a polyethylene composition.

[0004] This disclosure provides a backing layer. In one embodiment, the backing layer is composed of a polyethylene composition. The polyethylene composition comprises: (a) 15% to 25% by weight of a first polyethylene component having a molecular weight (Mw) greater than 200,000 g / mol and a density of 0.925 g / cc to 0.945 g / cc; (b) 20% to 35% by weight of a second polyethylene component having a molecular weight (Mw) less than 80,000 g / mol and a density of 0.915 g / cc to 0.950 g / cc; and (c) 40% to 65% by weight of a third polyethylene component having a molecular weight (Mw) less than 100,000 g / mol and a density of 0.940 g / cc to 0.965 g / cc. The polyethylene composition has a density of 0.935 g / cc to 0.958 g / cc and a melt index (I2) of 0.5 g / 10 min to 5.0 g / 10 min. This backing layer is for use in artificial turf. Attached Figure Description

[0005] Figure 1 This is a side view of an artificial turf according to one embodiment of the present disclosure.

[0006] Figure 2 This is a top plan view of the backing layer according to one embodiment of the present disclosure.

[0007] Figure 3 This is a schematic diagram of a dual-reactor polymerization system.

[0008] definition

[0009] Any reference to the periodic table is as in the version published by CRC Press, Inc. in 1990–1991. A group of elements in the table is referred to using a new notation for numbering the groups.

[0010] For the purposes of U.S. patent practice, any reference to a patent, patent application, or publication is incorporated herein by reference in its entirety (or its equivalent U.S. version thereof), especially the disclosure relating to definitions in the art (where there is no inconsistency with any definitions specifically provided in this disclosure) and common sense.

[0011] The numerical ranges disclosed herein include all values ​​from the lower limit to the upper limit, and include both the lower limit and the upper limit. For a range containing exact values ​​(e.g., a range between 1 or 2 or 3 and 5 or 6 or 7), any subranges between any two exact values ​​are included (e.g., the range 1 to 7 above includes subranges 1 to 2; 2 to 6; 5 to 7; 3 to 7; 5 to 6; etc.).

[0012] Unless stated to the contrary, implied by the context, or as is customary in the art, all parts and percentages are based on weight, and all test methods are current methods as of the date of this disclosure.

[0013] The terms “comprising,” “including,” “having,” and their derivatives do not exclude the presence of any additional components or processes. The term “consistently composed of” excludes any other components or processes except those essential to operability. The term “composed of” excludes any components or processes not specifically listed.

[0014] As used herein, the term "α-olefin" refers to an olefin having a double bond at the primary or α (alpha) position.

[0015] The terms "blend" and "polymer blend" refer to a composition of two or more polymers. Such blends may or may not be miscible. Such blends may or may not be phase-separated. Such blends may or may not contain one or more domain configurations, as determined by transmission electron spectroscopy, light scattering, X-ray scattering, and any other method known in the art. Blends are not laminates, but one or more layers of a laminate may contain blends. Such blends can be prepared as dry blends, formed in situ (e.g., in a reactor), or prepared as melt blends.

[0016] As used herein, the term "ethylene / α-olefin interpolymer" refers to an interpolymer comprising a majority (>50 mol%) amount of units derived from ethylene monomers in polymeric form, and the remaining units derived from one or more α-olefins. Typical α-olefins used to form ethylene / α-olefin interpolymers are C3-C64 ... 10 Olefins.

[0017] As used herein, the term "ethylene / α-olefin copolymer" refers to a copolymer comprising a majority amount (>50 mol%) of ethylene monomer and α-olefin as the only two monomer types.

[0018] "Ethylene-based polymers" or "polyethylene" refers to polymers containing a majority amount (>50 mol%) of units derived from ethylene monomers. This includes polyethylene homopolymers or copolymers (meaning units derived from two or more comonomers). Common forms of polyethylene known in the art include low-density polyethylene (LDPE); linear low-density polyethylene (LLDPE); ultra-low-density polyethylene (ULDPE); single-point catalytic linear low-density polyethylene, including both linear and substantially linear low-density resins (m-LLDPE); ethylene-based plastomers (POP) and ethylene-based elastomers (POE); medium-density polyethylene (MDPE); and high-density polyethylene (HDPE). The following description may help to understand the differences between some of these different polyethylene resins.

[0019] The term "LDPE" can also be referred to as "high-pressure ethylene polymer" or "highly branched polyethylene," and it is defined as meaning that the polymer is partially or wholly homopolymerized or copolymerized in an autoclave or tubular reactor at pressures above 14,500 psi (100 MPa) using a free radical initiator (such as peroxide) (see, for example, US 4,599,392, which is hereby incorporated herein by reference). LDPE resin typically has a viscosity of 0.916 g / cm³. 3 Up to 0.935 g / cm 3 The density within the range.

[0020] The term "LLDPE" encompasses two resins prepared using conventional Ziegler-Natta catalyst systems and chromium-based catalyst systems, as well as mono-site catalysts (including, but not limited to, substituted mono- or dicyclopentadienyl catalysts (commonly referred to as metallocenes), confined geometry catalysts, pyridinium amine catalysts, phosphine imine catalysts, and polyvalent aryloxy ether catalysts (commonly referred to as diphenylphenoxys), and comprising linear, substantially linear, or heterogeneous polyethylene copolymers or homopolymers. LLDPE contains less long-chain branching than LDPE, and LLDPE comprises substantially linear ethylene polymers, further defined in U.S. Patents 5,272,236, 5,278,272, 5,582,923, and 5,733,155; homogeneously branched linear ethylene polymer compositions, such as those in U.S. Patent No. 3,645,992; non-homogeneously branched ethylene polymers, such as those prepared according to the method disclosed in U.S. Patent No. 4,076,698; and / or blends thereof (such as those in U.S. Patent No. 4,076,698). (Those disclosed in US 3,914,342 or US 5,854,045). LLDPE can be manufactured by gas-phase, solution-phase, or slurry polymerization or any combination thereof, using any type of reactor or reactor configuration known in the art.

[0021] The term "MDPE" refers to a material with a density of 0.926 g / cm³. 3 Up to 0.935 g / cm 3 Polyethylene. “MDPE” is typically prepared using chromium or Ziegler-Natta catalysts or using single-point catalysts, including but not limited to substituted mono- or di-cyclopentadienyl catalysts (commonly known as metallocenes), restricted geometry catalysts, pyridinium amine catalysts, phosphine imine catalysts and polyvalent aryloxy ether catalysts (commonly known as diphenylphenoxy), and typically has a molecular weight distribution (“MWD”) greater than 2.5.

[0022] The term "HDPE" refers to a material with a density greater than 0.935 g / cm³. 3 And at most 0.980 g / cm 3 Polyethylene is generally prepared using Ziegler-Natta catalysts, chromium catalysts, or single-point catalysts (including but not limited to substituted mono- or di-cyclopentadienyl catalysts (commonly known as metallocenes), confined geometry catalysts, pyridineamine catalysts, phosphineimide catalysts, and polyvalent aryloxy ether catalysts (commonly known as diphenylphenoxy)).

[0023] The term "ULDPE" refers to a material with a density of 0.855 g / cm³. 3 Up to 0.912 g / cm 3Polyethylene, typically prepared using Ziegler-Natta catalysts, chromium catalysts, or single-point catalysts (including but not limited to substituted mono- or di-cyclopentadienyl catalysts (commonly known as metallocenes), confined geometry catalysts, pyridineamine catalysts, phosphine imine catalysts, and polyvalent aryloxy ether catalysts (commonly known as diphenylphenoxy)). ULDPE includes, but is not limited to, polyethylene (ethylene-based) plastomers and polyethylene (ethylene-based) elastomers. Polyethylene (ethylene-based) elastomers and plastomers typically have a density of 0.855 g / cm³. 3 Up to 0.912 g / cm 3 The density.

[0024] The term "multimodal" refers to a composition that can be characterized by having at least three (3) polymeric subcomponents with varying densities and weight-average molecular weights, and optionally, the composition may also have different melt index values. In one embodiment, multimodal can be defined by having at least three distinct peaks in a gel permeation chromatography (GPC) chromatogram showing a molecular weight distribution. In another embodiment, multimodal can be defined by having at least three distinct peaks in a crystallization elution fractionation (CEF) chromatogram showing a short-chain branching distribution. In yet another embodiment, multimodal can be defined by having at least three distinct peaks in an improved comonomer composition distribution (iCCD) elution curve. Multimodal includes compositions having three peaks in GPC, CEF, or iCCD, as well as compositions having more or fewer than three peaks, provided that the composition can be characterized by having at least three (3) polymeric subcomponents with varying densities and weight-average molecular weights according to the following test methods.

[0025] The term "trimodal polymer" refers to a multimodal ethylene-based polymer having three primary components: a first polyethylene component, a second polyethylene component, and a third polyethylene component. "Polyethylene component," such as "first polyethylene component," "second polyethylene component," or "third polyethylene component," refers to a sub-component (i.e., a multimodal or trimodal polymer) of the polyethylene composition disclosed herein, wherein each sub-component comprises ethylene monomers and optionally C3-C4. 12 Polyethylene with α-olefin comonomer.

[0026] The terms “nonwoven fabric” and “nonwoven fiber web” are used interchangeably in this document. “Nonwoven fabric” refers to a web-like structure having individual fibers or threads that are randomly inserted rather than in a identifiable manner as in knitted fabrics.

[0027] "Olefin-based polymers" are polymers containing a majority mol% of polymerizable olefin monomers (based on the total amount of polymerizable monomers) and optionally containing at least one comonomer. Non-limiting examples of olefin-based polymers include ethylene-based polymers and propylene-based polymers.

[0028] The term "polymer" refers to a macromolecular compound prepared by polymerizing monomers of the same or different types. "Polymers" include homopolymers, copolymers, terpolymers, interpolymers, etc. The term "interpolymer" refers to a polymer prepared by polymerizing at least two different types of monomers or comonomers. This includes, but is not limited to, copolymers (which typically refer to polymers prepared from two different types of monomers or comonomers), terpolymers (which typically refer to polymers prepared from three different types of monomers or comonomers), tetropolymers (which typically refer to polymers prepared from four different types of monomers or comonomers), etc.

[0029] "Propylene-based polymers" are polymers containing a majority amount (>50 mol%) of polymeric propylene and optionally including at least one comonomer. Propylene-based polymers typically contain at least 50 mol% of propylene-derived units based on the total amount of polymerizable monomers.

[0030] "Woven fabric" is a structure formed by warp and weft yarns. The warp and weft yarns interweave, so that the warp yarns extend longitudinally in the woven fabric, and the weft yarns extend perpendicular to the warp yarns.

[0031] Test methods

[0032] dtex It is a unit of measurement used to determine the linear density of filaments (or tapes) and is defined as the mass (in grams) of filament per 10,000 meters (m) of filament. For example, 168 dtex filament is filament with a mass of 168 g per 10,000 m of filament.

[0033] density The density of the total polyethylene composition was measured according to ASTM D792 Method B. Data are reported in Table 1A. For the first and second polyethylene components, density values ​​were obtained using Equations 1 to 16 and the deconvolution method described below. For the third polyethylene component, density values ​​were calculated using Equations 15 to 16. Density is expressed in grams per cubic centimeter (g / cc or g / cm³). 3 Report in units of 1. Individual component density data are reported in Table 3.

[0034] Conventional (Conv.) gel permeation chromatography (GPC)The chromatographic system consisted of a PolymerChar GPC-IR (Valencia, Spain) high-temperature GPC chromatograph equipped with an internal IR5 infrared detector (IR5). The autosampler oven chamber was set to 160°C, and the column chamber to 150°C. Four Agilent "Mixed A" 30cm 20µm linear mixed-bed columns were used. The chromatographic solvent was 1,2,4-trichlorobenzene containing 200 ppm butylated hydroxytoluene (BHT). The solvent source was nitrogen injection. The injection volume was 200 μL, and the flow rate was 1.0 mL / min.

[0035] The GPC column assembly was calibrated using 21 polystyrene standards with narrow molecular weight distributions, ranging from 580 to 8,400,000, arranged in six "cocktail" mixtures, with individual molecular weights spaced at least tenfold apart. The standards were purchased from Agilent Technologies. For molecular weights equal to or greater than 1,000,000, 0.025 g of polystyrene standard was prepared in 50 mL of solvent; for molecular weights less than 1,000,000, 0.05 g of polystyrene standard was prepared in 50 mL of solvent. The polystyrene standards were pre-dissolved at 80°C with gentle stirring for 30 min, then cooled, and the room temperature solution was transferred to an autosampler dissolution oven at 160°C for 30 min. Use Equation 1 to convert the peak molecular weight of polystyrene standards to the molecular weight of polyethylene (as described in Williams and Ward, J. Polym. Sci., Polym. Let., 6, 621 (1968)):

[0036]

[0037] Where M is the molecular weight, A has a value of 0.4129, and B equals 1.0.

[0038] A fifth-order polynomial was used to fit the calibration point for the corresponding polyethylene equivalent. Total plate counts were performed on the GPC column assembly using decane, which was introduced into the blank sample via a micropump controlled by a PolymerChar GPC-IR system. For four Agilent "Mixed A" 30 cm 20 μm linear mixed-bed columns, the plate count of the chromatographic system should be greater than 18,000.

[0039] Samples were prepared semi-automatically using PolymerChar Instrument Control software, with a target sample weight of 2 mg / ml. Solvent (containing 200 ppm BHT) was added to a pre-bubbled, diaphragm-capped vial via a PolymerChar high-temperature autosampler. The sample was then dissolved at 160°C for 2 hours with low-speed shaking.

[0040] Based on the GPC results, using the internal IR5 detector (measurement channel) of the PolymerChar GPC-IR chromatograph, according to Equation 2-4, the PolymerChar GPCOne was used. ™ The software calculates the Mn content based on the baseline-subtracted IR chromatograms 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) The calculation.

[0041]

[0042] To monitor deviations over time, a flow rate marker (decane) was introduced into each sample via a micropump controlled by a PolymerChar GPC-IR system. This flow rate marker (FM) was used to linearly correct the pump flow rate (nominal flow rate) for each sample by comparing the RV (RV(FM sample)) of the corresponding decane peak within the sample with the RV (RV(FM calibrated)) of the decane peak within the narrow standard calibration. It was then assumed that any variation in the decane marker peak time was linearly related to the flow rate (effective flow rate) throughout the run. The effective flow rate (relative to the narrow standard calibration) was calculated according to Equation 5 after calibration based on the flow marker peak system. (via PolymerChar GPCOne) ™ The software processes the flow marker peaks. Acceptable flow rate correction ensures that the effective flow rate is within + / - 0.5% of the nominal flow rate.

[0043]

[0044] GPC measurements were performed on both the total polyethylene composition and the polymer sampled from the first reactor containing the first polyethylene component and the second polyethylene component.

[0045] An improved method for analyzing comonomer content (iCCD)An improved method for comonomer content analysis (iCCD) was developed in 2015 (Cong and Parrott et al., WO2017040127A1). iCCD tests were performed using a Crystallization Elution Fractionation (CEF) instrument (Perimocha, Spain) equipped with an IR-5 detector (PolymerChar, Spain) and a two-corner light scattering detector model 2040 (Precision Detectors, now Agilent Technologies). A guard column filled with 20-27 micrometer glass (MoSCi Corporation, USA) was installed just before the IR-5 detector in the detector oven. o-Dichlorobenzene (ODCB, 99% anhydrous or industrial grade) was used. The sample was obtained from Merck Life Sciences (EMD). Chemicals obtained silica gel 40 (particle size 0.2–0.5 mm, catalog number 10181-3) (which could previously be used as a solvent for drying ODCB). The dried silica was packed into three empty HT-GPC columns to further purify ODCB as the eluent. The CEF instrument was equipped with an autosampler with N2 purging capability. ODCB was bubbled with dry nitrogen (N2) for one hour before use. Sample preparation was performed at 160 °C with shaking at a concentration of 4 mg / ml (unless otherwise specified) using the autosampler for 1 hour. The injection volume was 300 μl. The iCCD temperature profile was as follows: crystallization from 105 °C to 30 °C at 3 °C / min, thermal equilibration at 30 °C for 2 minutes (including a 2-minute elution time for the soluble fraction), and elution from 30 °C to 140 °C at 3 °C / min. The flow rate during crystallization was 0.0 ml / min. The flow rate during elution was 0.50 ml / min. Data was collected at one data point / second.

[0046] An iCCD column was filled with gold-plated nickel particles (Bright7GNM8-NiS, Nippon Chemical Industrial Co.) in a 15cm (length) × 1 / 4” (ID) stainless steel tube. Column filling and conditioning were performed according to references (Cong, R.; Parrott, A.; Hollis, C.; Cheatham, M. WO2017040127A1). The final pressure for TCB slurry filling was 150 bar.

[0047] Column temperature calibration was performed using a mixture of a reference material, linear homopolymer polyethylene (with zero comonomer content, melt index (I2) of 1.0, polydispersity Mw / Mn of approximately 2.6 by conventional gel permeation chromatography, 1.0 mg / ml), and ODCB containing eicosane (2 mg / ml). The iCCD temperature calibration consisted of four steps: (1) calculating the delay volume, which was defined as the measured peak elution temperature of eicosane minus the temperature offset between 30.00 °C and the measured peak elution temperature; and (2) subtracting the temperature offset of the elution temperature from the raw iCCD temperature data. It should be noted that the temperature shift is a function of experimental conditions, such as elution temperature, elution flow rate, etc.; (3) A linear calibration line for switching elution temperatures in the range of 30.00 °C and 140.00 °C is established such that the linear homopolymer polyethylene reference has a peak temperature at 101.0 °C and the eicosane has a peak temperature at 30.0 °C; (4) For the soluble fraction measured isothermally at 30 °C, the elution temperature below 30.0 °C is linearly extrapolated by using an elution heating rate of 3 °C / min, according to the reference (Cerk and Cong et al., US9,688,795).

[0048] A relationship between comonomer content and elution temperature of iCCD was constructed using 12 reference materials (ethylene homopolymers and ethylene-octene random copolymers prepared with unit-point metallocene catalysts, with ethylene equivalent weight-average molecular weights ranging from 35,000 to 128,000). All these reference materials were analyzed in the same manner as previously specified at 4 mg / mL. The reported peak elution temperatures follow the elution temperatures of iCCDs at octene mol% versus R² of 0.978 as shown in the figure.

[0049] By assuming a shape factor of 1 and all virial coefficients equal to zero, the molecular weight of the polymer and the molecular weight of the polymer fraction were determined directly from the LS detector (90-degree angle) and the concentration detector (IR-5) according to the Rayleigh-Gans-Debys approximation (Striegel and Yau, Modern Size Exclusion Liquid Chromatogram, pp. 242 and 263). An integration window was set to integrate the entire chromatogram over an elution temperature range of 23.0 °C to 120 °C (temperature calibration specified above).

[0050] Calculating molecular weight (Mw) from iCCD involves the following steps: Measuring the inter-detector bias. The bias is defined as the geometric volume shift between the LS detector and the concentration detector. It is calculated as the difference in elution volume (mL) of the polymer peak between the concentration detector and the LS chromatogram. This is converted to a temperature bias using the elution heat rate and elution flow rate. Linear high-density polyethylene (with zero comonomer content, melt index (I2) of 1.0, and polydispersity Mw / Mn of approximately 2.6 by conventional gel permeation chromatography) was used. The same experimental conditions as the normal iCCD method described above were used, except for the following parameters: crystallization from 140°C to 137°C at 10°C / min, thermal equilibration at 137°C for 1 min as the elution time for the soluble fraction, elution time for the soluble fraction (SF) of 7 min at 3°C / min from 137°C to 142°C. The flow rate during crystallization was 0.0 mL / min. The flow rate during elution was 0.80 mL / min. The sample concentration was 1.0 mg / mL. Prior to integration, each LS data point in the LS chromatogram was shifted to correct for inter-detector offset. The baseline minus the LS and concentration chromatograms over the entire elution temperature range of step (1) was integrated. The MW detector constant was calculated using known MW HDPE samples in the range of 100,000 Mw to 140,000 Mw and the area ratio of the integrated LS and concentration signals. The Mw of the polymer was calculated using the ratio of the integrated light scattering detector (90-degree angle) to the concentration detector and the MW detector constant.

[0051] On GPCOne ® Molecular weight calculation and calibration are performed in the software.

[0052] iCCD measurements were performed on both the total polyethylene composition and the polymer sampled from the first reactor containing the first and second polyethylene components. 。

[0053] Numerical deconvolution of bivariate data The density, molecular weight (Mw), and melt index (I2) of the first, second, and third polyethylene components were obtained by convolving the bivariate data. Microsoft Excel was used for this process. ® The solver (Solver) (2018) performs a combined iCCD-SCBD (from iCCD wt) iCCD (T) plotted against temperature (T) and GPC-MWD (wt from conventional GPC) GPC (lgMW) is deconvolved with the plot of lgMW. For iCCD-SCBD, the calculated weight fraction (wt) is obtained using the method described in the iCCD section (in the range of approximately 23 to 120°C). 总和,iCCD(T) The temperature (T) data is reduced to approximately 200 equally spaced data points to strike a balance between appropriate iteration speed and temperature resolution. The summation of a single or series of exponentially corrected Gaussian distributions (Equation 6) (up to 3 peaks per component) represents each component (wt). C,iCCD (T)), and sum the components to obtain the total weight (wt) at any temperature (T). 总和,iCCD (T)), as shown in equations 7A-7D.

[0054]

[0055] Where C refers to a component (C=1, 2, or 3), P refers to a peak (P=1, 2, or 3), and a 0,C,P a is the chromatographic area of ​​peak P of component C in °C. 1,C,P The peak center of the P-th peak of the C-th component, expressed in °C, is a 2,C,P a is the peak width of the P-th peak of the C-th component, expressed in °C. 3,C,P The peak tailing of the P-th peak of the C-th component is expressed in °C, and T is the elution temperature in °C. In the case of using a single exponentially corrected Gaussian distribution to represent the iCCD-SCBD of the components, y T,C,2 =y T,C,3 =0. In the case of using two exponentially corrected Gaussian distributions to represent the iCCD-SCBD of the components, only y T,C,3 =0.

[0056]

[0057] Weight fraction (wf) of each component from iCCD-SCBD deconvolution C,iCCD ) can be represented as

[0058]

[0059] Among them wf C1,iCCD The weight fraction of the first polyethylene component obtained from iCCD-SCBD deconvolution is wf. C2,iCCD The weight fraction of the second polyethylene component, wf, is obtained from iCCD-SCBD deconvolution. C3,iCCD It is the weight fraction of the third polyethylene component obtained from iCCD-SCBD deconvolution, and the sum of the fractions is normalized to 1.00.

[0060] For GPC-MWD, the MWD values ​​obtained from the regular GPC description section were imported into the same spreadsheet in increments of 0.01 lg(MW / (g / mol)) between 2.00 and 7.00 (a total of 501 data points). The following equation shows the MWD values ​​at a weight-average molecular weight of M w,目标And polydispersity (M) w / M n The Flory–Schulz distribution with a value of 2.0.

[0061]

[0062] Where wt F-S,i It is in lg(M) i / (g / mol))(M i The weight fraction of molecules in g / mol, where i is an integer from 0 to 500 to represent each data point on the GPC-MWD plot, and the corresponding lg(M i / (g / mol)) is 2+0.01×i.

[0063] Subsequently, use each lg(M) i The sum of a series of normal distributions at (g / mol) broadens the Flory-Schulz distribution. i The weight fraction of the normally distributed curve with a peak at (g / mol) remains the same as the original Flory-Schulz distribution. The broadened Flory-Schulz distribution curve can be described by the following equation.

[0064]

[0065] in It is in lg(M) i The molecular weight fraction at (g / mol) is given by j, where j is an integer in the range of 0 to 500, and σ is the standard deviation of the normal distribution. Therefore, the molecular weight distribution curves for all three components can be expressed by the following equation. The number-average molecular weight (Mn) can be calculated based on the broadened Flory-Schulz distribution. n(GPC) ), weight-average molecular weight (M w(GPC) ) and MWD (M w(GPC) / M n(GPC) ).

[0066]

[0067] in This is the normal distribution width parameter, with subscripts C1, C2, and C3 representing the first, second, and third polyethylene components, respectively. C1,GPC wf C2,GPC and wf C3,GPC These are the weight fractions of the first, second, and third polyethylene components from GPC-MWD, respectively.

[0068] Each of the paired components (first polyethylene component (C1), second polyethylene component (C2), and third polyethylene component (C3)) from iCCD-SCBD and GPC-MWD is considered to have equivalent quality for their respective technologies, as shown in Equations 14A-14E.

[0069]

[0070] The relative weight yield of each component can be initially estimated using process and catalyst data (including catalyst efficiency and reactor mass balance). Alternatively, the initial estimate of the weight fraction of each component can be compared by integrating a local region of the iCCD-SCBD or GPC-MWD plot of the polyethylene composition (paying particular attention to visible areas with defined peaks or peak inflection points). For example, if the separation is good, the peak area of ​​each component in the iCCD-SCBD curve can be estimated by lowering the vertical line between the peaks. Patents disclosed in WO201913394A1 and WO2019133373A1... Figure 2 Examples of iCCD-SCBD curves are provided. All of these disclosures are incorporated herein by reference. The correlation between molecular weight order and initial molecular weight estimates can be obtained from the peak positions of associated component regions in iCCD-SCBD and iCCD-MW plots, and should be expected to be consistent with GPC-CC measurements. In some cases, the initial assignment of peak areas and composition can be obtained from multi-peak GPC-MWD as a starting point and validated under iCCD-SCBD and iCCD-MW plots.

[0071] We can use a series of standard unit point samples with comonomer content (wt%) measured by NMR to obtain initial estimates of the peak elution temperature, width, and tail for each component in the iCCD-SCBD from the calibration of peak elution temperature, width, and tail. These calibrations can also inform the comonomer content of individual components from the measured peak elution temperature.

[0072] Microsoft Excel ® The solver is programmed to minimize a combination of the following two: wt 总和,GPC (lgM i The sum of squares of the residuals between the measured GPC-MWD and the measured GPC-MWD; and wt 总和,iCCD (T) is the sum of squares of the residuals between the measured iCCD-SCBD and the measured values ​​(where the sampling widths and areas of the two observed distributions are normalized relative to each other). When the GPC-MWD and iCCD-SCBD fits converge simultaneously, they are given equal weights. Initial estimates of weight fractions and peak widths in the iCCD-SCBD, along with molecular weight targets for each component, are used to enable Microsoft Excel.® The solver begins as described in this article.

[0073] The co-crystallization effect that distorts peak shapes in the iCCD is compensated by using exponentially corrected Gaussian (EMG) peak fitting and, in extreme cases, by using phase addition to describe multiple (up to 3) EMG peaks of a single component. Components produced by a single-center catalyst can be modeled by a single EMG peak. Components produced by a Ziegler-Natta catalyst can be modeled by 1, 2, or 3 EMG peaks or tails with long faces at low temperatures, sufficient to satisfy the single EMG peak of a Ziegler-Natta component with extremely high density and extremely low molecular weight targets on the iCCD-SCBD plot. In all cases, only a single broadened Flory-Schulz distribution (Equations 13A-13C) is used, and the weight fraction is assigned to the relevant sum of one or more components from the EMG components of the iCCD-SCBD model (Equations 14A-14E).

[0074] For the first and second polyethylene components prepared via a single-center catalyst, GPC deconvolution is determined by the normal distribution width parameter of Equations 13A and 13B ( or The polydispersity is limited to between 0.000 and 0.170 (corresponding to a polydispersity of approximately 2.00 to 2.33). In these cases, for the third polyethylene component, M in Equation 9... w,目标 It is limited to the minimum because its target is set to the minimum according to this specific reaction scheme. It should be noted that, according to the expected performance targets of the blends in the combined resin reactor, it is not limited to the minimum in all possible cases. (In iCCD-SCBD plotting (wt...)) iCCD The component peaks of the first and second polyethylene components were observed at the temperatures shown on the (T) and temperature curves, and plotted using an iCCD-MW plot (M). w(iCCD) M in the temperature curve w(iCCD) Two weight-average molecular weights (M) of the first and second polyethylene components were observed. w,目标 The ranking of the three components (preliminary estimate) is as follows. Therefore, the order of the molecular weights of the three components is well known. The reactor mass balance yields the mass percentage (Wf) of the third polyethylene component according to Equation 13C, or alternatively, it can be calculated from deconvolution using Equation 13D based on the strength of the known distribution models of iCCD and GPC, and the total weight fractions must be added to 1 (Equations 14A-14E).

[0075] Generally speaking, it has been found that using Excel... ®Approximately 20 solver iterations will typically converge well to a solution. If the peak order in the iCCD-MW plot is inconsistent with the measured molecular weight and the observed comonomer wt.% measured by GPC-CC, the data must be reconciled by changing the iteration start point (temperature or logMW) in Excel or slightly altering the width and tail factor so that the iteration continues to converge to a consistent solution between the measurements. Alternatively, the measurement resolution must be increased, or additional peaks can be added to the iCCD-SCBD to better approximate the elution peak shape of the individual components. If such a component is prepared separately, it can be modeled a priori using several EMG distributions.

[0076] Additionally, the predicted M of iCCD-MW can be generated by multiplying the weight-average molecular weight of each component in the GPC-MWD by the weight fraction of each component observed at each point along the iCCD-SCBD plot. w(iCCD) Response. Predicted M w(iCCD) M needs to be measured in iCCD-MW plotting w(iCCD) Consistent. The amount of comonomer incorporation can also be plotted as a function of elution temperature based on a series of known copolymer standards, and measurements of individual components from iCCD-MW and iCCD-SCBD plots can also be used. w(iCCD) The GPC-CC plot is predicted based on the amount of comonomer incorporation. The predicted GPC-CC plot needs to be consistent with the measured GPC-CC.

[0077] The correlation between peak temperature and density in iCCD-SCBD data was obtained using a series of linear ethylene-based polymer standard resins polymerized with a single-site catalyst having a melt index (I²) of approximately 1 g / 10 min, or a nominal weight-average molecular weight of approximately 105,000 g / mol by GPC, and a polydispersity (or MWD) of less than 2.3 by GPC. At least 10 standard resins with known comonomer contents, densities, and molecular weights in the density range of 0.87 g / cc to 0.96 g / cc were used. Peak temperature and density data were fitted to a 5th-order polynomial curve to obtain a calibration curve.

[0078] By fitting the peak width and peak tail to temperature with a linear line, the correlation between peak width and peak tail to peak temperature can be similarly obtained, which is very useful for initial estimation during deconvolution.

[0079] In the resin of this invention presented herein, the first and second polyethylene components are represented by the first two peaks between elution temperatures of 35°C and 90°C, directly from iCCD-SCBD deconvolution plots. Using a peak temperature versus density calibration curve, the "original density" (density) is calculated from the observed peak positions.原始 Density is determined by using Equation 15. 原始 (In g / cc) Corrected to density taking into account the contribution of molecular weight (in g / mol). 真实 (in g / cc):

[0080]

[0081] Where M w(GPC) It is the weight-average molecular weight of a single component deconvolved from GPC-MWD.

[0082] It can be based on the known density of the resin and the density of the first polyethylene component. 真实 Density of the second polyethylene component 真实 The density of the third polyethylene component is calculated based on the weight fraction of each component and Equation 16 below.

[0083]

[0084] The melt index (I2) of each polyethylene component can be estimated from its weight-average molecular weight using the following equation:

[0085]

[0086] Where M w(GPC) I2 is the weight-average molecular weight (in g / mol) of a single component deconvoluted from the GPC-MWD curve, and I2 is the melt index (in g / 10 min). Note that the amount of long-chain branching can change the coefficients. Furthermore, to determine the product composition, direct sampling of a single reactor with a single catalyst under identical reactor conditions, sampling of the first reactor in a tandem dual-reactor configuration, or sampling of both reactors in a parallel dual-reactor configuration can help determine the density, melt index (I2), GPC-MWD, and iCCD-SCBD of each individual component of the polyethylene composition, especially when the reaction is effectively terminated after the sampling point. This allows for better confirmation when the peak positions of the first and second polyethylene components cannot be adequately determined from the three-component mixture.

[0087] The analytical cross-grading in GPC-TREF (such as the PolymerChar CFC cell equipped with online light scattering (Valencia, Spain)) and the direct examination and quantification performed by similar calibration and calibration of the relationship with density in a bivariate space representing SCBD and molecular weight can also be used to measure the amount of each component in the composition or to more precisely distinguish each component, especially for initial estimation, or in cases where high co-crystallization or low resolution / distinction of the substance can occur, particularly in MWD and SCBD spaces. (Development of an Automated Cross-Fractionation Apparatus (TREF-GPC) for a Full Characterization of the Bivariate Distribution of Polyolefins. Polyolefin Characterization. Macromolecular Symposia, Vol. 257, 2007, pp. 13-28. A. Ortín, B. Monrabal, J. Sancho-Tello) Sufficient resolution must be achieved in both 1gMW and temperature space, and should be validated by direct composition ratio methods (e.g., IR-5 and light-scattering molecular weight measurements). See Characterization of Chemical Composition along the Molar Mass Distribution in Polyolefin Copolymers by GPC Using a Modern Filter-Based IR Detector. Polyolefin Characterization - ICPC 2012 Macromolecular Symposia, Vol. 330, 2013, pp. 63-80, A. Ortín, J. Montesinos, E. López, P. del Hierro, B. Monrabal, JRTorres-Lapasió, MCGarcía-Álvarez-Coque.The deconvolution of the components must be performed using a set of similar equations and similar calibrations that are tested by a series of unit point resins and resin blends.

[0088] Branching measurement The GPC system consisted of a 150°C high-temperature chromatograph equipped with a Polymer Char IR-5 infrared detector, a two-angle light scattering detector (Agilent 1260), and a differential viscometer from Polymer Char. Four PL-mixed A columns (7.5 mm x 300 mm), commercially available from Agilent, were installed in series before the IR-5 detector in a detector oven. 1,2,4-Trichlorobenzene (TCB, HPLC grade) and 2,5-di-tert-butyl-4-methylphenol (BHT) (such as those commercially available from Sigma-Aldrich) were obtained. Eight hundred mg of BHT was added to four liters of TCB. TCB containing BHT is now referred to as "TCB". Sample preparation was performed using an autosampler at 2 mg / mL with shaking at 160°C for 3 hours. The injection volume was 200 mL. The GPC temperature was 150°C, and the flow rate was 1 mL / min. GPC was calibrated using a series of narrow molecular weight (Mw) polystyrene standards.

[0089] The GPC column set was calibrated using 21 polystyrene standards with narrow molecular weight distributions, ranging from 580 to 9,835,000, arranged in a six-cocktail mixture, with individual molecular weights spaced at least tenfold apart. A fifth-order polynomial was used to fit the calibration points for the corresponding polyethylene equivalents. The molecular weights of the polystyrene standard peaks were then converted to polyethylene molecular weights.

[0090] Composition and MWD were measured using an IR-5 infrared detector. The composition detector was calibrated using a series of copolymer standards with different comonomer levels. (C) 13 NMR yielded the weight percent (wt%) comonomer levels for these samples. For each standard, composition-related signals were collected and labeled “Measured,” “Methylene” (CH2), and “Methyl” (CH3). When performing molecular weight correction, the “Measured” signal was used as the concentration signal, while the ratio of the “Methyl” to “Methylene” signals was used for composition calculations. A plot of these ratios from NMR was created comparing the comonomer weight percent to a series of standards. Linear regression of the data resulted in a good fit to the dataset.

[0091] Melt index The melt index (I²) was measured at 190°C and 2.16 kg according to ASTM D1238. Similarly, the melt index (I₂) was measured at 190°C and 10 kg according to ASTM D1238.10 Melt index (I2) values. These values ​​are reported in g / 10min, corresponding to the number of grams eluted per 10 minutes. These data for the total polyethylene composition are collected and reported in Table 2. Melt index (I2) values ​​for the first, second, and third polyethylene components are calculated according to Equations 15 to 16 and the deconvolution method described above and are shown in Table 3.

[0092] Shrinkage Cut a one-meter strip and immerse it in a 90°C hot oil bath for 20 seconds. Remove the strip from the bath, dry it manually, and remeasure its length. Heat shrinkage is expressed as the percentage reduction in length before and after immersion: Heat shrinkage = (Previous length - Later length) / Previous length * 100%.

[0093] Toughness and elongation A single 250 mm long strip was measured at 250 mm / min using a Zwick tensile force gauge until the fiber broke. Toughness was defined as the tensile force at break divided by the linear weight and expressed in cN / dtex, where “cN” is centinewtons. Ultimate elongation is the strain at fiber break, expressed as a percentage of deformation. Detailed Implementation

[0094] This disclosure provides a filament. In one embodiment, the filament is composed of a polyethylene composition. The polyethylene composition comprises (a) 15% to 25% by weight of a first polyethylene component. The first polyethylene component has a molecular weight (Mw) greater than 200,000 g / mol and a density of 0.925 g / cc to 0.945 g / cc. The polyethylene composition comprises (b) 20% to 35% by weight of a second polyethylene component. The second polyethylene component has a molecular weight (Mw) less than 80,000 g / mol and a density of 0.915 g / cc to 0.950 g / cc. The polyethylene composition comprises (c) 40% to 65% by weight of a third polyethylene component. The third polyethylene component has a molecular weight (Mw) less than 100,000 g / mol and a density of 0.940 g / cc to 0.965 g / cc. The polyethylene composition has a density of 0.935 g / cc to 0.958 g / cc and a melt index (I2) of 0.5 g / 10 min to 5.0 g / 10 min.

[0095] 1. Filament

[0096] As used herein, "filament" refers to a unidirectionally oriented, long strand of a cast extruded polymer material with a linear density of 100 dtex to 2500 dtex. Filaments can be monofilaments, film strips, or tapes.

[0097] In one embodiment, the filament is a strip. As used herein, "strip" is a unidirectionally oriented, elongated strand of a cast extruded polymer material having relatively parallel or substantially parallel sides and a linear density of 100 dtex to 2500 dtex. Strips typically have a length-to-diameter ratio greater than 10. Strips typically have a polygonal, square, or rectangular, or otherwise flat (i.e., "strip-like") cross-sectional shape. Strips have a thickness of 50 μm to 120 μm, or 70 μm to 100 μm, and a width of 0.1 mm to 5 mm, or 0.5 mm to 3 mm. Strips are typically longitudinally oriented (or otherwise stretched) to provide desired properties such as elongation and / or toughness.

[0098] In one embodiment, the tape has a line density of 300 dtex to 1500 dtex, or 700 dtex to 1500 dtex.

[0099] 2. Polyethylene component

[0100] The filament (or tape) is composed of a polyethylene composition. The polyethylene composition is an ethylene monomer and at least one C3-C... 12 The product of polymerization of an α-olefin comonomer or at least one C4-C8 α-olefin comonomer. Non-limiting examples of suitable α-olefin comonomers include propylene, 1-butene, 1-hexene, and 1-octene, and combinations thereof; or 1-butene, 1-hexene, 1-octene, and combinations thereof; or 1-hexene, 1-octene, and combinations thereof, or 1-octene.

[0101] The polyethylene composition comprises three components: (a) a first polyethylene component, (b) a second polyethylene component, and (c) a third polyethylene component. The polyethylene composition includes (a) a first polyethylene component of 15% to 25% by weight based on the total weight of the polyethylene composition, the first polyethylene component having a weight-average molecular weight (Mw) greater than 200,000 g / mol and a density of 0.925 g / cc to 0.945 g / cc. All individual values ​​and sub-ranges of 15% to 25% by weight are disclosed and included herein. For example, the polyethylene composition may contain 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, or 24% to 25%, 24%, 23%, 22%, 21%, 20%, 19%, 18%, 17%, or 16% by weight based on the total weight of the polyethylene composition. The first polyethylene component may have a Mw greater than 200,000 g / mol, or greater than 210,000 g / mol, or greater than 250,000 g / mol, or greater than 280,000 g / mol, or greater than 300,000 g / mol, or greater than 310,000 g / mol, or from 210,000 g / mol to 400,000 g / mol. The first polyethylene component may have a density of 0.925 g / cc to 0.945 g / cc, or 0.930 g / cc to 0.945 g / cc, or 0.930 g / cc to 0.940 g / cc. The density of the polyethylene composition components (e.g., the first polyethylene component, the second polyethylene component, and the third polyethylene component) is calculated according to the equations provided in the Test Methods section.

[0102] In one embodiment, the first polyethylene component has a peak temperature greater than 99.5°C in the elution profile obtained via improved comonomer composition distribution (iCCD). In some embodiments, the first polyethylene component is a homopolymer. In some embodiments, the first polyethylene component may include C3–C 12 α-Olefin comonomers. Exemplary α-olefin comonomers include, but are not limited to, propylene-1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, and 4-methyl-1-pentene. One or more α-olefin comonomers of the first polyethylene component may be selected from the group consisting of propylene, 1-butene, 1-hexene, and 1-octene, or, alternatively, from the group consisting of 1-butene, 1-hexene, and 1-octene, or, alternatively, from the group consisting of 1-hexene and 1-octene.

[0103] The polyethylene composition comprises (b) 20% to 35% by weight of a second polyethylene component having a molecular weight (Mw) of less than 80,000 g / mol and a density of 0.915 g / cc to 0.950 g / cc. All individual values ​​and sub-ranges of 20% to 35% by weight are disclosed and included herein. For example, the polyethylene composition may comprise 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, or 34% by weight of the total weight of the polyethylene composition, up to 35%, 34%, 33%, 32%, 31%, 30%, 29%, 28%, 27%, 26%, 25%, 24%, 23%, 22%, or 21% by weight of the second polyethylene component. The second polyethylene component may have a Mw of less than 80,000 g / mol, or less than 70,000 g / mol, or less than 60,000 g / mol, or less than 55,000 g / mol, or from 15,000 g / mol to 75,000 g / mol. The second polyethylene component may have a density of 0.915 g / cc to 0.950 g / cc, or 0.915 g / cc to 0.940 g / cc, or 0.915 g / cc to 0.935 g / cc, or 0.915 g / cc to 0.930 g / cc, or 0.915 g / cc to 0.925 g / cc.

[0104] The second polyethylene component can have different levels of C3-C 12 α-olefin comonomers are incorporated. In one embodiment, the second polyethylene component may have a higher C3-C ratio than the first polyethylene component. 12 α-olefin comonomers are incorporated. For example, the second polyethylene component can have 2% to 20% C3-C636 by weight. 12 α-olefin comonomer, or 3% to 19% by weight of C3-C 12 α-olefin comonomer, or 5% to 17% by weight of C3-C 12 α-Olefin comonomer. One or more α-olefin comonomers of the second polyethylene component may be selected from the group consisting of propylene, 1-butene, 1-hexene and 1-octene, or, in alternative schemes, from the group consisting of 1-butene, 1-hexene and 1-octene, or, in alternative schemes, from the group consisting of 1-hexene and 1-octene.

[0105] The polyethylene composition comprises (c) 40 wt% to 65 wt% of a third polyethylene component having a molecular weight (Mw) of less than 100,000 g / mol and a density of 0.940 g / cc to 0.965 g / cc. All individual values ​​and sub-ranges of 40 wt% to 65 wt% are disclosed and included herein. For example, the polyethylene composition may comprise 40 wt%, 41 wt%, 43 wt%, 45 wt%, 47 wt%, 49 wt%, 51 wt%, 53 wt%, 55 wt%, 57 wt%, 59 wt%, 61 wt% or 63 wt% to 65 wt%, 63 wt%, 61 wt%, 59 wt%, 57 wt%, 55 wt%, 53 wt%, 51 wt%, 49 wt%, 47 wt%, 45 wt%, 43 wt% or 41 wt% of the third polyethylene component based on the total weight of the polyethylene composition.

[0106] The third polyethylene component may have a molecular weight (Mw) of less than 100,000 g / mol, or less than 90,000 g / mol, or less than 80,000 g / mol, or from 15,000 g / mol to 90,000 g / mol. The third polyethylene component may have a density of 0.940 g / cc to 0.965 g / cc, or 0.942 g / cc to 0.965 g / cc, or 0.942 g / cc to 0.963 g / cc. The third polyethylene component may have different levels of C3-C. 12 α-olefin comonomers are incorporated. In one embodiment, the third polyethylene component may have a lower C3-C ratio than the first polyethylene component. 12 α-olefin comonomers are incorporated. For example, the third polyethylene component may have less than 10% by weight of C3-C4. 12 α-olefin comonomer, or 0.5% by weight or at least 10% by weight of C3-C 12 α-olefin comonomer, or 2% by weight or at least 10% by weight of C3-C 12 α-Olefin comonomer. One or more α-olefin comonomers of the third polyethylene component may be selected from the group consisting of propylene, 1-butene, 1-hexene and 1-octene, or, in alternative schemes, from the group consisting of 1-butene, 1-hexene and 1-octene, or, in alternative schemes, from the group consisting of 1-hexene and 1-octene.

[0107] In one embodiment, the filament (or tape) is composed of a polyethylene composition having (a) a first polyethylene component, (b) a second polyethylene component and (c) a third polyethylene component, and the polyethylene composition has one, some or all of the following properties:

[0108] (i) densities of 0.935 g / cc to 0.958 g / cc, or 0.936 g / cc to 0.954 g / cc, or 0.935 g / cc to 0.950 g / cc; and / or

[0109] (ii) a melt index (I2) of 0.5 g / 10 min to 5.0 g / 10 min, or 0.5 g / 10 min to 3.0 g / 10 min, or 0.5 g / 10 min to 2.0 g / 10 min, or 1.0 g / min to 2.0 g / min; and / or

[0110] (iii) Mw / Mn of 3.5 to 10, or 3.5 to 8.0, or 3.5 to 6.0, or 3.5 to 4.0; and / or

[0111] (iv) Mz / Mw of 3.0 to 5.5, or 3.0 to 4.5, or 3.0 to 3.9, or 3.0 to 3.6; and / or

[0112] (v) 8.5 to 15.0, or 8.5 to 14.0, or 8.5 to 13.0, or 8.5 to 12.5 of I 10 / I2 value; and

[0113] The belt has one, some, or all of the following characteristics:

[0114] (vi) Linear densities of 300 dtex to 1500 dtex, or 700 dtex to 1500 dtex, or 725 dtex to 775 dtex; and / or

[0115] (vii) Shrinkage values ​​of 0.1% to less than 1.0% or 0.1% to 0.5%; and / or

[0116] (viii) 20% to 30% elongation; and / or

[0117] (ix) Toughness from 2.0 cN / dtex to 3.0 cN / dtex.

[0118] The filament, tape, and / or polyethylene composition may further comprise one or more optional additives. Non-limiting examples of suitable additives include antioxidants, pigments, colorants, UV stabilizers, UV absorbers, curing agents, crosslinking aids, accelerators and retarders, processing aids, fillers, coupling agents, UV absorbers or stabilizers, antistatic agents, nucleating agents, slip agents, plasticizers, lubricants, viscosity control agents, tackifiers, anti-caking agents, surfactants, bulking oils, acid removers, and metal passivators. In one embodiment, a colorant, such as SICOLEN, may be added in amounts less than about 10% by weight, less than about 8% by weight, less than about 6% by weight, or even less than about 4% by weight. ™Green 85-125345 (purchased from BASF). In another embodiment, a processing aid, such as ARX-741 (purchased from Argus), may be added in amounts less than about 2% by weight, less than about 1.5% by weight, or even less than about 1% by weight. Based on the weight of the formulation, the additive may be used in amounts ranging from about 0.001% by weight to more than about 10% by weight.

[0119] 3. Artificial turf / backing layer

[0120] In one implementation, the filament is a strip and is used as one or more components in the artificial turf. Figure 1 An embodiment of an artificial turf 10 having a primary backing layer 13 having a plurality of artificial turf yarns 11 extending upward therefrom. As used herein, the term "artificial turf" refers to a carpet-like covering having substantially upright, or upright, polymer strands of artificial turf yarns 11 extending upward from a substrate, which is the primary backing layer 13. The artificial turf 10 may optionally include a filler 12 and a shock-absorbing layer 15. The artificial turf 10 also includes a secondary backing layer 14. The secondary backing layer 14 contacts the primary backing layer 13. Figure 1 As shown, the artificial turf yarn 11, primary backing layer 13, secondary backing layer 14, and shock-absorbing layer 15 can be attached to each other, and the filler 12 can be distributed on top of the artificial turf yarn 11. The artificial turf 10 can be placed on the ground 16 or other desired surfaces.

[0121] The artificial turf 10 of this invention comprises a plurality of artificial turf yarns 11 extending upward from a primary backing layer 13. As used herein, the term "artificial turf yarn" or "yarn" hereinafter includes fibrous ribbon yarn, co-extruded ribbon yarn, monoribbon yarn, and monofilament yarn. A "fibrillated ribbon" or "fibrillated ribbon yarn" is a cast extruded film cut into strips (typically about 1 cm wide), stretched, and with long slits cut (fibrillated) into strips, so that the grass blades are strip-shaped. "Monofilament yarn" is extruded into individual yarns or strands having a desired cross-sectional shape and thickness, and then oriented and relaxed in a hot oven. The artificial turf yarns form the polymer strands of the artificial turf. Artificial turf requires resilience, toughness, flexibility, stretch, and durability. Therefore, artificial turf yarn excludes yarns used for fabrics (i.e., woven and / or knitted fabrics).

[0122] The artificial turf yarn 11 is composed of a polymer material. Non-limiting examples of polymer materials suitable for the yarn include olefin-based polymers (such as propylene-based polymers and / or ethylene-based polymers), polyesters, nylons, and combinations thereof. In one embodiment, the artificial turf yarn 11 is composed of an ethylene-based polymer. In another embodiment, the artificial turf yarn 11 is composed of the polyethylene composition of the present invention with (a) a first polyethylene component, (b) a second polyethylene component, and (c) a third polyethylene component.

[0123] Artificial turf 10 may optionally include infill 12. Non-limiting examples of infill materials include granular rubber particles such as SBR (styrene-butadiene rubber) recycled from automobile tires, EPDM (ethylene / propylene / terpolymer), other vulcanized rubbers or rubber recycled from belts, thermoplastic elastomers (TPE), thermoplastic vulcanized rubbers (TPV), and mixtures thereof.

[0124] The primary backing layer 13 is one or more sheets to which artificial turf yarn 11 is sewn or woven, such that the artificial turf yarn 11 extends outward from the top side of the primary backing layer 13. The primary backing layer can be a polymer sheet of woven fabric, a polymer sheet of nonwoven fabric, or a perforated polymer sheet. The primary backing layer provides dimensional stability to the artificial turf system.

[0125] In one embodiment, the primary backing layer (interchangeably referred to as the "backing layer") comprises a polyethylene composition of the present invention as previously disclosed herein. The polyethylene composition comprises (a) 15% to 25% by weight of a first polyethylene component. The first polyethylene component has a molecular weight (Mw) greater than 200,000 g / mol and a density of 0.925 g / cc to 0.945 g / cc. The polyethylene composition comprises (b) 20% to 35% by weight of a second polyethylene component. The second polyethylene component has a molecular weight (Mw) less than 80,000 g / mol and a density of 0.915 g / cc to 0.950 g / cc. The polyethylene composition comprises (c) 40% to 65% by weight of a third polyethylene component. The third polyethylene component has a molecular weight (Mw) less than 100,000 g / mol and a density of 0.940 g / cc to 0.965 g / cc. The polyethylene composition has a density of 0.935 g / cc to 0.958 g / cc and a melt index (I2) of 0.5 g / 10 min to 5.0 g / 10 min.

[0126] In one embodiment, the primary backing layer (or backing layer) is a woven fabric composed of warp filaments and weft filaments. Figure 2The weft filaments are woven or otherwise interlaced in an "up-down-up-down" manner, such that the weft filaments are perpendicular to the warp filaments. At least one of the warp or weft filaments is composed of the polyethylene composition of the present invention.

[0127] In one embodiment, each of the warp filaments and the weft filaments is composed of the polyethylene composition of the present invention. In other words, the warp filaments are composed of the polyethylene composition of the present invention, and the weft filaments are composed of the polyethylene composition of the present invention combined with (a) a first polyethylene component, (b) a second polyethylene component, and (c) a third polyethylene component.

[0128] In one implementation, the warp filaments are warp tapes, and the weft filaments are weft tapes.

[0129] In one embodiment, the backing layer is a perforated sheet. The perforated sheet is composed of the polyethylene composition of the present invention and (a) a first polyethylene component, (b) a second polyethylene component and (c) a third polyethylene component.

[0130] This disclosure relates to trimodal polyethylene compositions that can be used as filaments / ribbons in the production of artificial turf backing layers. The polyethylene compositions of this invention provide desired performance properties for primary backing layers, such as low shrinkage, toughness, and / or elongation. Without wishing to be bound by any particular theory, it is believed that the unique design of the polyethylene compositions of this invention—including, for example, the weight fraction of the three-component composition and the first polyethylene component, the Z-average molecular weight (Mz), and the average short-chain branching level (SCB) in the portion between log(Mw) 4.0 and 5.0—is important. logMw4-5 — This provides improved processability, improved elongation, and reduced shrinkage characteristics. The polyethylene compositions of this invention can be incorporated into artificial turf, filaments, strips, and / or artificial turf backing layers to enhance the recyclability of artificial turf.

[0131] It is believed that the HMW, near-homogeneous fraction, namely the first polyethylene component (a), anchors the overall structure of the strip, so that when the strip is exposed to higher temperatures, the LMW fractions (the second and third polyethylene components (b and c)) do not shrink because they are directly anchored by the first polyethylene component (a). Furthermore, the polyethylene compositions of the present invention have an MI of 0.5 g / 10 min to 5.0 g / 10 min and a high Ig of 8.5 to 15. 10 / I2, which helps with proper extrusion processing.

[0132] Embodiments of this disclosure will now be described in detail, by way of example and not limitation.

[0133] Example

[0134] 1. Materials

[0135] The materials of the embodiments of the invention (“IE”) and the comparative samples (“CS”) are listed in Tables 1A, 1B and 1C below.

[0136] Table 1A

[0137]

[0138] 1. Preparation of IE1

[0139] All feedstocks (monomers and comonomers) and process solvents (narrow-boiling-range, high-purity isoparaffin solvent, Isopar-E) were purified using molecular sieves before being introduced into the reaction environment. Hydrogen was supplied pressurized at a high purity level without further purification. The monomer feed stream to the reactor was pressurized to above the reaction pressure via a mechanical compressor. The solvent and comonomer feed streams were pressurized to above the reaction pressure via pumps. Individual catalyst components were manually diluted in batches with purified solvent and pressurized to above the reaction pressure. All reaction feed streams were measured by mass flow meters and independently controlled by a computer-automated valve control system.

[0140] The two reactor systems are used in series. The first continuous solution polymerization reactor consists of a liquid-filled, non-adiabatic isothermal circulating reactor that mimics a continuous stirred tank reactor (CSTR) with heat removal. All fresh solvent, monomer, comonomer, hydrogen, and catalyst components can be independently controlled. The total fresh feed stream (solvent, monomer, comonomer, and hydrogen) to the first reactor is temperature-controlled to maintain a single solution phase by passing the feed stream through a heat exchanger. The total fresh feed to each polymerization reactor is injected into the reactor at three locations, with approximately equal reactor volumes between each injection location. The fresh feed is controlled by each injector receiving one-third of the total fresh feed mass flow rate. The catalyst components are injected into the polymerization reactor at two distinct locations, with similar reactor volumes between each injection location and receiving half of the total flow rate for each injection. The primary catalyst component feed is computer-controlled to maintain the reactor monomer conversion at a specified target. The secondary catalyst component is fed at a specified molar ratio to the total catalyst (catalyst-B molar ratio = (catalyst-B) mol / (catalyst-A + catalyst-B) mol × 100). A boron-containing co-catalyst component is fed based on the specified molar ratio to the total catalyst metals (primary + secondary) fed to the reactor. An Al-containing co-catalyst component is fed to maintain a specified Al concentration in the reactor. Immediately following each reactor feed or catalyst injection point, the material stream is mixed with the contents of the circulating polymerization reactor using a static mixing element. The reactor contents are continuously circulated through a heat exchanger responsible for removing a significant amount of reaction heat, and the temperature on the coolant side is responsible for maintaining the isothermal reaction environment at the specified temperature. Circulation around the reactor loop is provided by a pump. A sample system is maintained to periodically collect material from the first circulating reactor. After collection, the samples are dried in a vacuum oven and submitted for GPC and iCCD analysis. GPC and iCCD analyses provide measurements of the polymer split between the primary and secondary catalysts in the first reactor loop; the results can be used to adjust the molar ratio of the secondary catalyst to achieve the desired polymer split within the first reactor loop.

[0141] The effluent from the first polymerization reactor (containing solvent, monomer, comonomer, hydrogen, catalyst components and polymer) leaves the first reactor and is added to the second reactor.

[0142] The second continuous solution polymerization reactor consists of a liquid-filled, non-adiabatic isothermal circulating reactor that mimics a continuous stirred tank reactor (CSTR) with heat removal. All fresh solvent, monomer, comonomer, hydrogen, and catalyst components can be independently controlled. The total fresh feed stream (solvent, monomer, comonomer, and hydrogen) to the second reactor is temperature-controlled to maintain a single solution phase by passing the feed stream through a heat exchanger. The total fresh feed to each polymerization reactor is injected into the reactor at two locations, with approximately equal reactor volumes between each injection point. The fresh feed is controlled by receiving half the total fresh feed mass flow rate at each injector. The catalyst component (catalyst component 3) is injected into the polymerization reactor via injection needles. The primary catalyst component feed is computer-controlled to maintain the reactor monomer conversion at a specified target. The cocatalyst component is fed based on a specified molar ratio to the primary catalyst component. Immediately following each reactor feed and catalyst injection point, the material stream is mixed with the contents of the circulating polymerization reactor using static mixing elements. The contents of each reactor are continuously circulated through a heat exchanger, which removes most of the heat of reaction, and the temperature on the coolant side is responsible for maintaining the isothermal reaction environment at the specified temperature. Circulation around each reactor loop is provided by a pump.

[0143] After exiting the second reactor loop, the effluent from the second / final reactor enters the insulated tube of the post-reactor, where the total volume is approximately 21.4% of the combined volume of the two circulating reactors. The reaction continues for a period before entering the mixing zone, where it is stopped by deactivating the catalyst through the addition of a suitable reagent (water) and its reaction. At the same reactor outlet location, additional additives are added for polymer stabilization (typical antioxidants suitable for stability during extrusion and blown film manufacturing processes, such as octadecyl 3,5-di-tert-butyl-4-hydroxycinnamate, tetra(methylene(3,5-di-tert-butyl-4-hydroxycinnamate))methane, and tris(2,4-di-tert-butyl-phenyl)phosphite) and acid neutralization (typically the acid scavenger calcium stearate).

[0144] After catalyst deactivation and the addition of additives, the reactor effluent enters a volatilization system where polymers are removed from the non-polymer stream. The separated polymer melt is granulated and collected. The non-polymer stream is separated through various devices that handle most of the ethylene removed from the system. Most of the solvent and unreacted comonomers are recycled back to the reactor after passing through a purification system. Small amounts of solvent and comonomers are removed from the process.

[0145] Figure 3The reactor feed data stream is illustrated in the diagram, corresponding to the values ​​in Table 1B used to generate IE1. Presenting the data allows for easy handling of the reaction system as a once-through flow diagram, taking into account the complexity of the solvent recycling system.

[0146] The catalysts and co-catalysts used to generate IE1 are provided in Table 1B below. The polymerization conditions used to generate IE1 are provided in Table 1C below.

[0147] Table 1. Catalysts and co-catalysts for B-IE1

[0148]

[0149] Table 1. Aggregation conditions for C-IE1

[0150]

[0151] Based on the above test methods, the density, melt index (I2), and I of samples PE1 and PE2 were measured and compared. 10 / I2, Mz, Mw / Mn, Mz / Mn. Tables 2, 3, 4, and 5 below provide the characteristics of IE1 and the comparative samples PE2 and PE3.

[0152] Table 2 - Data on Polyethylene Compositions

[0153]

[0154] The density, Mw, and weight % (wt.%) of each of the components (comparisons) (i.e., polyethylene component 1 (comparison 1), polyethylene component 2 (comparison 2), and polyethylene component 3 (comparison 3)) were measured according to the test methods described above. Table 3 provides the results.

[0155] Table 3

[0156]

[0157] 2. Preparation of the belt

[0158] The belt is produced in a production line with fibrils. The method begins by extruding a cast film of the polyethylene composition of the present invention, which is immediately immersed in a water bath for quenching. The cast film is then removed from the water bath and dried to remove any moisture or water. The film is then fibrillated into smaller films. The width varies depending on the type of belt to be extruded (2 mm for warp and 5 mm for weft).

[0159] After fibrillation, a stretching step is then performed. The membrane is stretched in an oven (105°C to 115°C) at a stretch ratio of 4 to 5. The term "stretch ratio" (or "SR") is defined as the stretch ratio of the membrane between the oven inlet and the oven outlet. It is measured as the ratio of the linear velocity at the oven inlet to the linear velocity at the oven outlet.

[0160] Following the stretching step, an annealing step is performed. In the annealing step, the filament is heated in an oven (105°C to 115°C) and / or rolled at a controlled speed to control shrinkage.

[0161] Finally, fibrillation is performed in each strip of the tape. For the primary backing layer, needle fibrillation is performed to create small cuts in the membrane, which will facilitate subsequent yarn tufting.

[0162] The warp tape is 1 mm wide, and two tapes are wound together to form a single warp tape. The weft tape is 2.2 mm to 2.3 mm wide, and they are used separately.

[0163] The stretch ratio and annealing were kept constant for all samples, i.e., 5.2 SR and 10% annealing. The production process conditions are provided in Table 4 below.

[0164] Table 4. Processing conditions for belt production .

[0165]

[0166] The comparison samples (PE1, PE2) and the embodiment of the present invention (IE1) were run at 750 dB. The characteristics of the band are provided in Table 5 below.

[0167] Table 5. Mechanical properties of the produced belts .

[0168]

[0169] CS1 and IE1 are directly comparable; both resins have the same density (0.950 g / cc) and the same molecular weight index (MI) (1.5 g / 10 min to 1.6 g / 10 min). CS1 has a shrinkage rate of 1.6%, while IE1 has a shrinkage rate of 0.4%. Compared to CS1, the trimodal nature of the polyethylene composition of the present invention in IE1 provides a 4-fold improvement in shrinkage rate (i.e., less shrinkage).

[0170] CS2 has a higher density (0.955 g / cc) than IE1 (0.950 g / cc). However, IE1 still achieves a lower shrinkage rate (0.4%) compared to CS2 (1.1%).

[0171] Generally, shrinkage rate is related to resin density, and under the same conditions, polyethylene resins with higher density typically have lower shrinkage rates than polyethylene resins with lower density. CS2 has a higher density than CS1 and IE1 (CS2 density 0.955 g / cc vs. CS1 / IE1 density 0.950 g / cc). CS2 exhibits a shrinkage rate of 1.1%. The applicant unexpectedly discovered a polyethylene resin that achieves a low shrinkage rate (0.4%) in the tape. Without being bound by any particular theory, it is believed that the low shrinkage rate in the IE1 tape is due to the molecular structure of the trimodal polyethylene resin in IE1. The applicant’s IE1 polyethylene composition’s ability to achieve a lower shrinkage rate (0.4%) at a density of 0.950 g / cc compared to the 1.1% shrinkage rate of CS1 polyethylene resin with the same density (0.950 g / cc), and the ability of IE1 to achieve a lower shrinkage rate (0.4%) at a lower density (0.950 g / cc) compared to the 1.1% shrinkage rate of CS2 at a higher density (0.955 g / cc) are unexpected.

[0172] It is particularly desirable that this disclosure is not limited to the embodiments and descriptions contained herein, but includes modifications of those embodiments, including portions of embodiments appearing within the scope of the following claims and combinations of elements of different embodiments.

Claims

1. A filament, said filament comprising: A polyethylene composition, the polyethylene composition comprising (a) 15% to 25% by weight of a first polyethylene component, the first polyethylene component having a molecular weight (Mw) greater than 200,000 g / mol and a density of 0.925 g / cc to 0.945 g / cc; (b) 20% to 35% by weight of a second polyethylene component, the second polyethylene component having a molecular weight (Mw) of less than 80,000 g / mol and a density of 0.915 g / cc to 0.950 g / cc; and (c) 40% to 65% by weight of a third polyethylene component, said third polyethylene component having a molecular weight (Mw) of less than 100,000 g / mol and a density of 0.940 g / cc to 0.965 g / cc; and The polyethylene composition has Densities ranging from 0.935 g / cc to 0.958 g / cc, and Melt index (I2) from 0.5 g / 10 min to 5.0 g / 10 min.

2. The filament according to claim 1, wherein the polyethylene composition has an Mz / Mw ratio of 3.0 to 5.

5.

3. The filament according to any one of claims 1 to 2, wherein the polyethylene composition has a molecular weight distribution (Mw / Mn) of 3.5 to 10.

4. The filament according to any one of claims 1 to 3, wherein the polyethylene composition has a melt index I10 / melt index I2 (I10 / I2) value of 8.5 to 15.

5. The filament according to any one of claims 1 to 4, wherein the filament has a linear density of 300 dtex to 1500 dtex.

6. The filament according to any one of claims 1 to 5, wherein the filament has a shrinkage value of 0.1% to less than 1.0%.

7. The filament according to any one of claims 1 to 6, wherein the filament has an elongation of 20% to 30%.

8. The filament according to any one of claims 1 to 7, wherein the filament has a toughness of 2.0 cN / dtex to 3.0 cN / dtex.

9. The filament according to any one of claims 1 to 8, wherein the filament is a tape.

10. A backing layer, the backing layer comprising: A polyethylene composition, the polyethylene composition comprising (a) 15% to 25% by weight of a first polyethylene component, the first polyethylene component having a molecular weight (Mw) greater than 200,000 g / mol and a density of 0.925 g / cc to 0.945 g / cc; (b) 20% to 35% by weight of a second polyethylene component, the second polyethylene component having a molecular weight (Mw) of less than 80,000 g / mol and a density of 0.915 g / cc to 0.950 g / cc; and (c) 40% to 65% by weight of a third polyethylene component, said third polyethylene component having a molecular weight (Mw) of less than 100,000 g / mol and a density of 0.940 g / cc to 0.965 g / cc; and The polyethylene composition has Densities ranging from 0.935 g / cc to 0.958 g / cc, and Melt index (I2) from 0.5 g / 10 min to 5.0 g / 10 min.

11. The backing layer of claim 10, wherein the backing layer is a base fabric, the base fabric comprising... One or more warp filaments; and One or more weft filaments, said one or more weft filaments being woven through said warp filaments; and At least one of the warp filaments and the weft filaments is composed of the polyethylene composition.

12. The backing layer according to claim 11, wherein the warp filaments are composed of the polyethylene composition; and The weft filaments are composed of the polyethylene composition.

13. The backing layer according to claim 12, wherein the warp filaments are warp tapes; and The weft filament is a weft tape.

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