Polymer compositions with enhanced aging and reduced shrinkage

Abstract

The polymer composition comprises (i) a copolymer of ethylene and an alpha olefin comonomer, the copolymer having a density of 0.945 g / cc to 0.960 g / cc, (ii) an ethylene-based polymer, and (iii) a polyethylene glycol. The combination of (i) and (ii) has a density of 10 5 g / mol to 10 5.5 g / mol weight average molecular weight range having a high Mw comonomer content of 3.2 wt% or greater based on the total weight of (i) and (ii) combined, wherein 15 wt% or more of the total weight of the polymer composition is a comonomer having a molecular weight of 10 5 g / mol to 10 5.5 g / mol range, wherein the polymer composition has a relevant comonomer content of 0.6 wt% or greater, and wherein the polymer composition has a density of 0.945 g / cc or greater as measured according to ASTM D792.

Description

Background Art Technical Field

[0002] The present disclosure relates generally to polymer compositions, and more particularly to polymer compositions that exhibit enhanced aging characteristics and reduced shrinkage. Background Art

[0004] Fiber optic cables can be used to transmit data at high speeds over long distances and are therefore being used in an increasing number of applications. Fiber optic cables are trending towards smaller sizes and lighter weight, which requires new mini-cable and micro-cable technologies for high fiber density construction. Due to the thin walls and high extrusion speeds used in the manufacture of these fiber optic cables, the performance properties of the polymer jacket on the cable are particularly important. The first property that the polymer jacket must exhibit is a density of 0.945 grams per cubic centimeter ("g / cc") or greater, so that the polymer jacket is sufficiently rigid and exhibits a hardness that can withstand abuse. The second property that the polymer jacket material must exhibit is a cyclic temperature shrinkage of 2.5% or less to minimize signal attenuation. The third property that the polymer jacket must exhibit is a retained tensile elongation at break of 75% or greater after heat aging to ensure cable life. The fourth property that the polymer jacket must exhibit is an environmental stress crack resistance ("ESCR") of 400 hours or greater to again ensure cable life.

[0005] A conventional approach to addressing the first characteristic is to include high-density polyethylene ("HDPE") in the jacket material. HDPE is a cost-effective jacket material that typically exhibits increased strength due to its high crystallinity and density of 0.945 g / cc or greater. The morphology of HDPE is a plurality of crystallites and an amorphous tie molecule phase that holds the crystalline phase together. HDPE provides the polymer composition with the necessary crystallinity to address the first characteristic, but the structure of some HDPEs makes them susceptible to cyclic temperature shrinkage, loss of mechanical properties after heat aging, and low ESCR, which can degrade the second, third, and fourth characteristics.

[0006] Attempts to address the shortcomings of HDPE used in cable jacketing have been reported. For example, World Intellectual Property Organization Publication No. 2014 / 099360A1 ("the '360 Publication") discloses the use of bimodal HDPE and modified components to address performance issues in polymer jacketing. The '360 Publication explains that HDPE and polymer architecture are already nearing optimality, and further investment would increase turnaround time and cost. Therefore, modified components should be incorporated to improve cyclic temperature shrinkage.

[0007] Thus, surprisingly, polymer compositions useful as cable jacketing have been discovered that exhibit a density of 0.945 g / cc or greater, a cyclic temperature shrinkage of 2.5% or less, a retained tensile elongation at break of 75% after heat aging, and an ESCR of 400 hours or greater due to a modified polymer architecture. Summary of the Invention

[0008] The present invention provides a polymer composition useful as cable jacketing that exhibits a density of 0.945 g / cc or greater, cyclic temperature shrinkage of 2.5% or less, a retained tensile elongation at break of 75% after heat aging, and an unconditioned ESCR of 400 or greater due to a modified polymer architecture.

[0009] The present invention is the result of the discovery that by using a bulk density of 0.945 g / cc and ５ g / mol to 10 5.5 The polymer composition can exhibit the above properties by blending polymers exhibiting a high Mw comonomer content of 3.2 wt% or greater in the molecular weight range of g / mol and having a relevant comonomer content of 0.6 wt% or greater. During the final deformation stage, under tensile loading, the tie chains are oriented along the tensile axis. Strong tie chains are required in order for strain hardening to occur and to meet the requirement of 75% retained tensile elongation at break after heat aging. Without being bound by theory, it is believed that at 10 5 g / mol to 10 5.5 The high Mw comonomer content of 3.2 wt% or greater in the molecular weight range of g / mol and the associated comonomer content of 0.6 wt% or greater strengthens the tethering molecules between the crystallites, resulting in a polymer composition with a density of 0.945 g / cc or greater, while enhancing the elongation at break and ESCR of the polymer composition. In addition, the cyclic temperature shrinkage is maintained at less than 2.5%.

[0010] The invention is particularly useful in cable jacketing.

[0011] According to a first feature of the present disclosure, the polymer composition comprises (i) a copolymer of ethylene and an alpha-olefin comonomer, the copolymer having a density of 0.945 g / cc to 0.960 g / cc, (ii) an ethylene-based polymer, and (iii) a polyethylene glycol. The combination of (i) and (ii) has a relative density of 100 g / cc as measured by GPC. 5 g / mol to 10 5.5 g / mol weight average molecular weight range having a high Mw comonomer content of 3.2 wt% or greater based on the total weight of (i) and (ii) combined, wherein 15 wt% or more of the total weight of the polymer composition is a comonomer having a molecular weight of 105 g / mol to 10 5.5 g / mol range, wherein the polymer composition has a relevant comonomer content of 0.6 wt% or greater, and wherein the polymer composition has a density of 0.945 g / cc or greater as measured according to ASTM D792.

[0012] According to a second feature of the present disclosure, the polymer composition includes 35 to 85 wt% of the copolymer, based on the total weight of the polymer composition.

[0013] According to the third feature of the present disclosure, the polymer composition includes 0.5 wt % to 1 wt % of polyethylene glycol based on the total weight of the polymer composition and the polyethylene glycol.

[0014] According to the fourth feature of the present disclosure, the polymer composition includes 15 wt% to 30 wt% of the ethylene-based polymer, based on the total weight of the polymer composition, and the ethylene-based polymer is a linear low density polyethylene having a density of 0.91 g / cc to 0.93 g / cc as measured according to ASTM D792.

[0015] According to the fifth feature of the present disclosure, the polymer composition comprises 15 wt% to 19 wt% of the vinyl polymer, based on the total weight of the polymer composition, and the vinyl polymer is a plastomer having a density of 0.90 g / cc to 0.91 g / cc as measured according to ASTM D792.

[0016] According to the sixth feature of the present disclosure, the polymer composition contains 45 wt% to 55 wt% of an ethylene-based polymer based on the total weight of the polymer composition, and the ethylene-based polymer is a high-density polyethylene having a density of 0.93 g / cc to 0.95 g / cc as measured according to ASTM D792.

[0017] According to the seventh feature of the present disclosure, the polymer composition includes 10 wt% to 15 wt% of the vinyl polymer, based on the total weight of the polymer composition, and the vinyl polymer is an elastomer having a density of 0.80 g / cc to 0.90 g / cc as measured according to ASTM D792.

[0018] According to the eighth feature of the present disclosure, the combination of (i) and (ii) is 10 5 g / mol to 10 5.5 The invention can be used in the molecular weight range of 1000 g / mol with a high Mw comonomer content of 12.0 wt% or less.

[0019] According to the ninth feature of the present disclosure, 30 wt% or less of the total weight of the polymer composition is a polymer having a molecular weight of 100 nm as measured by GPC. ５ g / mol to 10 5.５ Combinations of (i) and (ii) with molecular weights in the g / mol range.

[0020] According to a tenth feature of the present disclosure, a coated conductor includes: a conductor; and a polymer composition at least partially disposed around the conductor. DETAILED DESCRIPTION

[0021] As used herein, the term "and / or," when used in the context of a list of two or more items, means that any one of the listed items can be used alone, or any combination of two or more of the listed items can be used. For example, if a composition is described as comprising components A, B, and / or C, the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.

[0022] Unless otherwise stated, all ranges are inclusive.

[0023] Test methods refer to the most recent test methods as of the priority date of this document, unless the date is expressed as a two-digit hyphenated test method number. Reference to a test method includes reference to both the testing association and the test method number. Test method organizations are referenced by one of the following abbreviations: ASTM refers to ASTM International (formerly the American Society for Testing and Materials); IEC refers to the International Electrotechnical Commission; EN refers to European Standard; DIN refers to the German Institute for Standardization; and ISO refers to the International Organization for Standardization.

[0024] As used herein, unless otherwise indicated, the term weight percent ("wt%") refers to the weight percent of a component based on the total weight of the polymer composition.

[0025] The melt index (I2) values ​​herein are values ​​determined according to ASTM method D1238 at 190 degrees Celsius (°C) and a mass of 2.16 kilograms (Kg), and are provided in units of grams eluted per ten minutes ("g / 10 min."). 21 ) values ​​refer to values ​​measured according to ASTM method D1238 at 190 degrees Celsius (°C) and 21.6 kg mass, and are provided in units of grams eluted per ten minutes (g / 10 min.).

[0026] Density values ​​herein refer to values ​​measured at 23°C according to ASTM D792 and are provided in grams per cubic centimeter ("g / cc").

[0027] As used herein, Chemical Abstract Services registration numbers ("CAS#") refer to the unique numerical identifier most recently assigned to a chemical compound by Chemical Abstract Services as of the priority date of this document.

[0028] polymer composition

[0029] The polymer composition comprises a copolymer of ethylene and an alpha-olefin comonomer, an ethylene-based polymer, and polyethylene glycol. The polymer composition in an unfilled state has a density of 0.945 g / cc to 0.970 g / cc. For example, the unfilled density of the polymer composition may be 0.945 g / cc or greater, or 0.946 g / cc or greater, or 0.948 g / cc or greater, or 0.950 g / cc or greater, or 0.952 g / cc or greater, or 0.954 g / cc or greater, or 0.955 g / cc or greater, or 0.956 g / cc or greater, or 0.958 g / cc or greater, or 0.960 g / cc or greater, or 0.962 g / cc or greater, or 0.964 g / cc or greater, or 0.966 g / cc or greater, or less, or 0.954 g / cc or less, or 0.952 g / cc or less, or 0.950 g / cc or less, or 0.948 g / cc or less, or 0.946 g / cc or less. As defined herein, the "unfilled state" of a polymer composition is defined as a polymer composition consisting essentially of a copolymer of ethylene and an alpha-olefin comonomer, an ethylene-based polymer, and polyethylene glycol.

[0030] Copolymer

[0031] One component of the polymer composition is a copolymer of ethylene and an alpha olefin comonomer. "Polymer" refers to a macromolecular compound comprising multiple monomers of the same or different types bonded together. "Copolymer" refers to a polymer prepared from two different monomer types. Copolymers may include ethylene and one or more C3-C 20Alpha-olefin comonomers such as propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, and 1-octene. Copolymers can have a unimodal or multimodal molecular weight distribution. As used herein, "unimodal" means that a polymeric material has a molecular weight distribution ("MWD") such that its gel permeation chromatography ("GPC") curve exhibits only a single peak and no discernible second peak or even a shoulder or hump relative to this single peak. In contrast, as used herein, "bimodal" means that the MWD in the GPC curve exhibits the presence of two component polymers, such as by having two peaks, or where one component can be indicated by a hump, shoulder, or tail relative to the peak of the other component polymer.

[0032] The copolymer can comprise 50 wt % or more, 60 wt % or more, 70 wt % or more, 80 wt % or more, 85 wt % or more, 90 wt % or more, or 91 wt % or more, or 92 wt % or more, or 93 wt % or more, or 94 wt % or more, or 95 wt % or more, or 96 wt % or more, or 97 wt % or more, or 97.5 wt % or more, as measured using nuclear magnetic resonance (NMR) or Fourier transform infrared (FTIR) spectroscopy. or 98 wt % or more, or 99 wt % or more, and at the same time 99.5 wt % or less, or 99 wt % or less, or 98 wt % or less, or 97 wt % or less, or 96 wt % or less, or 95 wt % or less, or 94 wt % or less, or 93 wt % or less, or 92 wt % or less, or 91 wt % or less, or 90 wt % or less, or 85 wt % or less, or 80 wt % or less, or 70 wt % or less, or 60 wt % or less of ethylene.

[0033] The copolymer can be a high density polyethylene ("HDPE"). The copolymer can be prepared in a slurry reactor, a gas phase reactor, or a solution reactor using a Ziegler-Natta, chromium-based, constrained geometry, or metallocene catalyst. The copolymer comprises at least 50% by weight of ethylene polymerized therein, or at least 70% by weight, or at least 80% by weight, or at least 85% by weight, or at least 90% by weight, or at least 95% by weight of ethylene in polymerized form, based on the weight of the ethylene-based polymer, as determined by nuclear magnetic resonance spectroscopy.

[0034] The copolymer has a density of 0.945 g / cc to 0.960 g / cc. For example, the copolymer can have a density of 0.945 g / cc or greater, or 0.946 g / cc or greater, or 0.948 g / cc or greater, or 0.950 g / cc or greater, or 0.952 g / cc or greater, or 0.954 g / cc or greater, or 0.955 g / cc or greater, or 0.956 g / cc or greater, or 0.958 g / cc or greater, while at the same time being 0.960 g / cc or less, or 9.58 g / cc or less, or 9.56 g / cc or less, or 0.955 g / cc or less, or 9.54 g / cc or less, or 9.52 g / cc or less, or 9.50 g / cc or less, or 9.48 g / cc or less, or 9.46 g / cc or less, as measured according to ASTM D792.

[0035] The copolymer may have a viscosity of 0.1 g / 10 min. or greater, or 0.3 g / 10 min. or greater, or 0.5 g / 10 min. or greater, or 1.0 g / 10 min. or greater, or 1.5 g / 10 min. or greater, or 2.0 g / 10 min. or greater, or 2.5 g / 10 min. or greater, or 3.0 g / 10 min. or greater, or 3.5 g / 10 min. or greater, or 4.0 g / 10 min. or greater, or 4.5 g / 1 0 min. or more, or 5.0 g / 10 min. or more, or 5.5 g / 10 min. or more, or 6.0 g / 10 min. or more, or 6.5 g / 10 min. or more, or 7.0 g / 10 min. or more, or 7.5 g / 10 min. or more, or 8.0 g / 10 min. or more, or 8.5 g / 10 min. or more, or 9.0 g / 10 min. or more, or 9.5 g / 10 min. or more, and at the same time 10.0 g / 10 min. or less, or 9.5 g / 10 min. or less, or 9.0 g / 10 min. or less, or 8.5 g / 10 min. or less, or 8.0 g / 10 min. or less, or 7.5 g / 10 min. or less, or 7.0 g / 10 min. or less, or 6.5 g / 10 min. or less, or 6.0 g / 10 min. or less, or 5.5 g / 10 min. or less, or 5.0 g / 10 min. or less, or 4.5 g / 10 min. or less, or 4.0 g / 10 min. or less, or 3.5 g / 10 min. or less, or 3.0 g / 10 min. or less, or 2.5 g / 10 min. or less, or 2.0 g / 10 min. or less, or 1.5 g / 10 min. or less, or 1.0 g / 10 min. or less, or 0.5 g / 10 min. or less, or 0.3 g / 10 min. or less melt index (I2).

[0036] The copolymer may have a viscosity of 90 g / 10 min. or greater, or 92 g / 10 min. or greater, or 94 g / 10 min. or greater, or 96 g / 10 min. or greater, or 98 g / 10 min. or greater, or 100 g / 10 min. or greater, or 102 g / 10 min. or greater, or 104 g / 10 min. or greater, or 106 g / 10 min. or greater, or 108 g / 10 min. or greater, or 110 g / 10 min. or greater, or 112 g / 10 min. or greater, or 114 g / 10 min. or greater, or 116 g / 10 min. or greater, or 118 g / 10 min., while at the same time or less, or 108 g / 10 min. or less, or 106 g / 10 min. or less, or 104 g / 10 min. or less, or 102 g / 10 min. or less, or 100 g / 10 min. or less, or 98 g / 10 min. or less, or 96 g / 10 min. or less, or 94 g / 10 min. or less, or 92 g / 10 min. or less melt index (I 21 ).

[0037] Polymer composition can comprise the multipolymer of 35 % by weight to 80 % by weight.For example, polymer composition can comprise the multipolymer of 35 % by weight to 80 % by weight.For example, polymer composition can comprise the multipolymer of 35 % by weight or more, or 40 % by weight or more, or 45 % by weight or more, or 50 % by weight or more, or 55 % by weight or more, or 60 % by weight or more, or 65 % by weight or more, or 70 % by weight or more, or 75 % by weight or more, or 80 % by weight or more, and simultaneously 85 % by weight or less, or 80 % by weight or less, or 75 % by weight or less, or 70 % by weight or less, or 65 % by weight or less, or 60 % by weight or less, or 55 % by weight or less, or 50 % by weight or less, or 45 % by weight or less, or 40 % by weight or less.

[0038] vinyl polymers

[0039] As described above, the polymer composition comprises an ethylene-based polymer. As used herein, an "ethylene-based" polymer is a polymer in which greater than 50% by weight of the monomers are ethylene, although other comonomers may also be used. The ethylene-based polymer may include ethylene and one or more C3-C 20Alpha-olefin comonomers such as propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, and 1-octene. The vinyl polymers may have a unimodal or multimodal molecular weight distribution and may be used alone or in combination with one or more other types of vinyl polymers (e.g., blends of two or more vinyl polymers that differ from one another in terms of monomer composition and content, preparation catalysis, molecular weight, molecular weight distribution, density, etc.). If blends of vinyl polymers are employed, the polymers may be blended by any in-reactor or post-reactor method.

[0040] The ethylene-based polymer may comprise 50 wt % or more, 60 wt % or more, 70 wt % or more, 80 wt % or more, 85 wt % or more, 90 wt % or more, or 91 wt % or more, or 92 wt % or more, or 93 wt % or more, or 94 wt % or more, or 95 wt % or more, or 96 wt % or more, or 97 wt % or more, or 97.5 wt % or more, as measured using nuclear magnetic resonance (NMR) or Fourier transform infrared (FTIR) spectroscopy. %, or 98 wt % or more, or 99 wt % or more, while at the same time 99.5 wt % or less, or 99 wt % or less, or 98 wt % or less, or 97 wt % or less, or 96 wt % or less, or 95 wt % or less, or 94 wt % or less, or 93 wt % or less, or 92 wt % or less, or 91 wt % or less, or 90 wt % or less, or 85 wt % or less, or 80 wt % or less, or 70 wt % or less, or 60 wt % or less of ethylene. Other units of the ethylene-based polymer may include C3, or C4, or C6, or C8, or C 10 , or C 12 , or C 16 , or C 18 , or C 20 α-Olefins such as propylene, 1-butene, 1-hexene, 4-methyl-1-pentene and 1-octene.

[0041] The polymer composition may comprise from 15% to 55% by weight of the vinyl polymer. For example, the polymer composition may comprise 15% by weight or more, or 20% by weight or more, or 25% by weight or more, or 30% by weight or more, or 35% by weight or more, or 40% by weight or more, or 45% by weight or more, or 50% by weight or more, while at the same time comprising 55% by weight or less, or 50% by weight or less, or 45% by weight or less, or 40% by weight or less, or 35% by weight or less, or 30% by weight or less, or 25% by weight or less, or 20% by weight or less of the vinyl polymer.

[0042] The vinyl polymer may be linear low density polyethylene ("LLDPE"). In the LLDPE example, the polymer composition may include 15 wt% or more, or 16 wt% or more, or 17 wt% or more, or 18 wt% or more, or 19 wt% or more, or 20 wt% or more, or 21 wt% or more, or 22 wt% or more, or 23 wt% or more, or 24 wt% or more, or 25 wt% or more, or 26 wt% or more, or 27 wt% or more, or 28 wt% or more, or 29 wt% or more, while at the same time being 30 wt% or less, or 29 wt% or less, or 28 wt% or less, or 27 wt% or less, or 26 wt% or less, or 25 wt% or less, or 24 wt% or less, or 23 wt% or less, or 22 wt% or less, or 21 wt% or less, or 20 wt% or less, or 19 wt% or less, or 18 wt% or less, or 17 wt% or less, or 16 wt% or less of ethylene-based polymer. As described in accordance with ASTM Examples of LLDPE of ethylene-based polymers may have a % OD of 0.910 g / cc or greater, or 0.912 g / cc or greater, or 0.914 g / cc or greater, or 0.916 g / cc or greater, or 0.918 g / cc or greater, or 0.920 g / cc or greater, or 0.922 g / cc or greater, or 0.924 g / cc or greater, or 0.926 g / cc or greater, or 0.928 g / cc or greater, while at the same time having a density of 0.930 g / cc or less, or 0.928 g / cc or less, or 0.926 g / cc or less, or 0.924 g / cc or less, or 0.922 g / cc or less, or 0.920 g / cc or less, or 0.918 g / cc or less, or 0.916 g / cc or less, or 0.914 g / cc or less, or 0.912 g / cc or less. Examples of LLPDEs for vinyl polymers may have 0.1 g / 10 min. or greater, or 0.2 g / 10 min. or greater, or 0.4 g / 10 min. or greater, or 0.56 g / 10 min. or greater, or 0.6 g / 10 min. or greater, or 0.8 g / 10 min. or greater, or 1.0 g / 10 min. or greater, or 1.2 g / 10 min. or greater, or 1.4 g / 10 min. or greater. or less, or 1.4 g / 10 min. or less, or 1.2 g / 10 min. or less, or 1.0 g / 10 min. or less, or 0.8 g / 10 min. or less, or 0.6 g / 10 min. or less, or 0.56 g / 10 min. or less, or 0.4 g / 10 min. or less, or 0.2 g / 10 min. or less of a melt index (I2).Exemplary LLPDEs of ethylene-based polymers may have a melt index (MI) of 10 g / 10 min. or greater, or 20 g / 10 min. or greater, or 40 g / 10 min. or greater, or 56 g / 10 min. or greater, or 60 g / 10 min. or greater, or 80 g / 10 min. or greater, or 100 g / 10 min. or greater, or 120 g / 10 min. or greater, or 140 g / 10 min. or greater, while at the same time being 150 g / 10 min. or less, or 140 g / 10 min. or less, or 120 g / 10 min. or less, or 100 g / 10 min. or less, or 80 g / 10 min. or less, or 60 g / 10 min. or less, or 56 g / 10 min. or less, or 40 g / 10 min. or less, or 20 g / 10 min. or less. 21 ).

[0043] The vinyl polymer can be a plastomer. In a plastomer example, the polymer composition can include 15 wt % or more, or 16 wt % or more, or 17 wt % or more, or 18 wt % or more, or 19 wt % or more, while 20 wt % or less, or 19 wt % or less, or 18 wt % or less, or 17 wt % or less, or 16 wt % or less of the vinyl polymer. As measured according to ASTM D792, the plastomer example of the vinyl polymer can have 0.900 g / cc or greater, or 0.901 g / cc or greater, or 0.902 g / cc or greater, or 0.903 g / cc or greater, or 0.904 g / cc or greater, or 0.905 g / cc or greater, or 0.906 g / cc or greater, or 0.907 g / cc or greater, or 0.908 g / cc or greater, or 0.909 g / cc or greater. / cc or greater, while having a density of 0.910 g / cc or less, or 0.909 g / cc or less, or 0.908 g / cc or less, or 0.907 g / cc or less, or 0.906 g / cc or less, or 0.905 g / cc or less, or 0.904 g / cc or less, or 0.903 g / cc or less, or 0.902 g / cc or less, or 0.901 g / cc or less. Examples of plastomers of vinyl polymers may have a density of 0.1 g / 10 min. or greater, or 0.2 g / 10 min. or greater, or 0.4 g / 10 min. or greater, or 0.6 g / 10 min. or greater, or 0.8 g / 10 min. or greater, or 0.86 g / 10 min. or greater, or 1.0 g / 10 min. or greater, or 1.2 g / 10 min. or greater, or 1.4 g / 10 min. or greater. or less, or 1.4 g / 10 min. or less, or 1.2 g / 10 min. or less, or 1.0 g / 10 min. or less, or 0.8 g / 10 min. or less, or 0.6 g / 10 min. or less, or 0.56 g / 10 min. or less, or 0.4 g / 10 min. or less, or 0.2 g / 10 min. or less of a melt index (I2).Examples of plastomers of ethylene-based polymers may have a density of 10 g / 10 min. or greater, or 12 g / 10 min. or greater, or 14 g / 10 min. or greater, or 16 g / 10 min. or greater, or 18 g / 10 min. or greater, or 20 g / 10 min. or greater, or 22 g / 10 min. or greater, or 24 g / 10 min. or greater, or 26 g / 10 min. or greater, or 28 g / 10 min. or greater, or 30 g / 10 min. or greater, or 32 g / 10 min. or greater, or 34 g / 10 min. or greater. or less, or 30 g / 10 min. or less, or 28 g / 10 min. or less, or 26 g / 10 min. or less, or 24 g / 10 min. or less, or 22 g / 10 min. or less melt index (I). 21 ).

[0044] The ethylene-based polymer may be HDPE. In the HDPE example, the polymer composition may include 45 wt% or more, or 46 wt% or more, or 47 wt% or more, or 48 wt% or more, or 49 wt% or more, or 50 wt% or more, or 51 wt% or more, or 52 wt% or more, or 53 wt% or more, or 54 wt% or more, while at the same time comprising 55 wt% or less, or 54 wt% or less, or 53 wt% or less, or 52 wt% or less, or 51 wt% or less, or 50 wt% or less, or 49 wt% or less, or 48 wt% or less, or 47 wt% or less, or 46 wt% or less of the ethylene-based polymer. As described in accordance with ASTM Examples of HDPE ethylene-based polymers may have a g / cc value of 0.930 g / cc or greater, or 0.932 g / cc or greater, or 0.934 g / cc or greater, or 0.936 g / cc or greater, or 0.938 g / cc or greater, or 0.940 g / cc or greater, or 0.942 g / cc or greater, or 0.944 g / cc or greater, or 0.946 g / cc or greater, or 0.948 g / cc or greater, while at the same time having a density of 0.950 g / cc or less, or 0.948 g / cc or less, or 0.946 g / cc or less, or 0.944 g / cc or less, or 0.942 g / cc or less, or 0.940 g / cc or less, or 0.938 g / cc or less, or 0.936 g / cc or less, or 0.934 g / cc or less, or 0.932 g / cc or less. Examples of HDPE ethylene-based polymers may have a viscosity of 0.1 g / 10 min. or greater, or 0.2 g / 10 min. or greater, or 0.4 g / 10 min. or greater, or 0.6 g / 10 min. or greater, or 0.8 g / 10 min. or greater, or 0.86 g / 10 min. or greater, or 1.0 g / 10 min. or greater, or 1.2 g / 10 min. or greater, or 1.4 g / 10 min. or greater. or less, or 1.4 g / 10 min. or less, or 1.2 g / 10 min. or less, or 1.0 g / 10 min. or less, or 0.8 g / 10 min. or less, or 0.6 g / 10 min. or less, or 0.56 g / 10 min. or less, or 0.4 g / 10 min. or less, or 0.2 g / 10 min. or less of a melt index (I2).

[0045] The vinyl polymer can be an elastomer. In an example of an elastomer, the polymer composition can include 10 wt% or more, or 11 wt% or more, or 12 wt% or more, or 13 wt% or more, or 14 wt% or more, while at the same time including 15 wt% or less, or 14 wt% or less, or 13 wt% or less, or 12 wt% or less, or 11 wt% or less of the vinyl polymer. An example of an elastomer that is a vinyl polymer can have a viscosity as measured according to ASTM D792 of 0.80 g / cc or greater, or 0.81 g / cc or greater, or 0.82 g / cc or greater, or 0.83 g / cc or greater, or 0.84 g / cc or greater, or 0.85 g / cc or greater, or 0.86 g / cc or greater, or 0.87 g / cc or greater, or 0.874 g / cc or greater, or 0.88 g / cc or greater, or 0.89 g / cc or greater, while at the same time having a density of 0.90 g / cc or less, or 0.89 g / cc or less, or 0.88 g / cc or less, or 0.874 g / cc or less, or 0.87 g / cc or less, or 0.86 g / cc or less, or 0.85 g / cc or less, or 0.84 g / cc or less, or 0.83 g / cc or less, or 0.82 g / cc or less, or 0.81 g / cc or less. Examples of elastomeric vinyl polymers may have a viscosity of 0.1 g / 10 min. or greater, or 0.2 g / 10 min. or greater, or 0.4 g / 10 min. or greater, or 0.6 g / 10 min. or greater, or 0.8 g / 10 min. or greater, or 0.86 g / 10 min. or greater, or 1.0 g / 10 min. or greater, or 1.2 g / 10 min. or greater, or 1.4 g / 10 min. or greater. or less, or 1.4 g / 10 min. or less, or 1.2 g / 10 min. or less, or 1.0 g / 10 min. or less, or 0.8 g / 10 min. or less, or 0.6 g / 10 min. or less, or 0.56 g / 10 min. or less, or 0.4 g / 10 min. or less, or 0.2 g / 10 min. or less of a melt index (I2).

[0046] It is understood that two or more of the LLDPE, plastomer, HDPE, and elastomer examples of ethylene-based polymers may be used in the polymer composition without departing from the teachings provided herein.

[0047] polyethylene glycol

[0048] The polymer composition comprises polyethylene glycol. Polyethylene glycol refers to an oligomer or polymer of ethylene oxide represented by structure (I):

[0049] H-(O-CH2-CH2) q -OH structure (I)

[0050] Wherein q refers to the number of repeating units in the polyethylene glycol polymer. The q value of polyethylene glycol can range from 200 to 10,000.

[0051] The polyethylene glycol may have a weight average molecular weight of 10,000 g / mol or greater, or 20,000 g / mol or greater, or 30,000 g / mol or greater, or 35,000 g / mol or greater, or 40,000 g / mol or greater, or 45,000 g / mol or greater, or 50,000 g / mol or greater, or 55,000 g / mol or greater, or 60,000 g / mol or greater, or 65,000 g / mol or greater, or 70,000 g / mol or greater, or 75,000 g / mol or greater, or 80,000 g / mol or greater, or 85,000 g / mol or greater, or 90,000 g / mol or greater, or 95,000 g / mol or greater. or more, while at the same time being 100,000 g / mol or less, or 90,000 g / mol or less, or 85,000 g / mol or less, or 80,000 g / mol or less, or 75,000 g / mol or less, or 70,000 g / mol or less, or 65,000 g / mol or less, or 60,000 g / mol or less, or 55,000 g / mol or less, or 50,000 g / mol or less, or 45,000 g / mol or less, or 40,000 g / mol or less, or 35,000 g / mol or less, or 30,000 g / mol or less, or 25,000 g / mol or less, or 20,000 g / mol or less, or 15,000 g / mol or less. Blends of polyethylene glycols of different average molecular weights may be used in the polymer composition in equal or varying weight percentages.

[0052] Polyethylene glycol can be 0.1 wt % to 2 wt % of the polymer composition. The polymer composition can include 0.1 wt % or more, or 0.2 wt % or more, or 0.3 wt % or more, or 0.4 wt % or more, or 0.5 wt % or more, or 0.6 wt % or more, or 0.7 wt % or more, or 0.8 wt % or more, or 0.9 wt % or more, or 1.0 wt % or more, or 1.1 wt % or more, or 1.2 wt % or more, or 1.3 wt % or more, or 1.4 wt % or more, or 1.5 wt % or more, or 1.6 wt % or more, or 1.7 wt % or more, or 1.8 wt % or more, or 1.9 wt % or more %, while at the same time 2.0 wt % or less, or 1.9 wt % or less, or 1.8 wt % or less, or 1.7 wt % or less, or 1.6 wt % or less, or 1.5 wt % or less, or 1.4 wt % or less, or 1.3 wt % or less, or 1.2 wt % or less, or 1.1 wt % or less, or 1.0 wt % or less, or 0.9 wt % or less, or 0.8 wt % or less, or 0.7 wt % or less, or 0.6 wt % or less, or 0.5 wt % or less, or 0.4 wt % or less, or 0.3 wt % or less, or 0.2 wt % or less of polyethylene glycol.

[0053] Copolymers and vinyl polymers

[0054] As described above, the copolymer and the vinyl polymer each contain a comonomer. By adjusting the weight percent of the comonomer and the molecular weight fraction of the comonomer present in the combined copolymer and vinyl polymer, the polymer composition can meet or exceed the target mechanical properties described above. The portion of the polymer for which the comonomer content should be adjusted is the portion having a weight average molecular weight of about 10 5 g / mol to 10 5.5 The ratio of polymers with a weight average molecular weight of about 10 5 g / mol to 10 5.5 The proportion of polymer in g / mol is defined herein as the "high Mw weight fraction," as explained in more detail below in the GPC test method.

[0055] The polymer composition may comprise a high Mw weight fraction of 0.02 or greater or 0.04 or greater or 0.06 or greater or 0.08 or greater or 0.10 or greater or 0.12 or greater or 0.14 or greater or 0.16 or greater or 0.18 or greater or 0.20 or greater or 0.22 or greater or 0.24 or greater or 0.26 or greater or 0.28 or greater while at the same time being 0.30 or less or 0.28 or less or 0.26 or less or 0.24 or less or 0.22 or less or 0.20 or less or 0.18 or less or 0.16 or less or 0.14 or less or 0.12 or less or 0.10 or less or 0.08 or less or 0.06 or less or 0.04 or less or 0.02 or less. The weight percent of the high Mw weight fraction of the copolymer and ethylene-based polymer combined is calculated by multiplying the weight fraction value by 100.

[0056] The average comonomer content of the high Mw weight fraction ("high Mw comonomer content") is determined from short chain branching data obtained by GPC, as described below in the GPC Test Methods. The polymer composition may comprise 3.2 wt% or greater, or 3.4 wt% or greater, or 3.6 wt% or greater, or 3.8 wt% or greater, or 4.0 wt% or greater, or 4.2 wt% or greater, or 4.4 wt% or greater, or 4.6 wt% or greater, or 4.8 wt% or greater, or 5.0 wt% or greater, or 5.2 wt% or greater, or 5.4 wt% or greater, or 5.6 wt% or greater, or 5.8 wt% or greater, while the same % or less, or 4.8 wt% or less, or 4.6 wt% or less, or 4.4 wt% or less, or 4.2 wt% or less, or 4.0 wt% or less, or 3.8 wt% or less, or 3.6 wt% or less, or 3.4 wt% or less of high Mw comonomer content.

[0057] The product of the high Mw weight fraction and the high Mw comonomer content (defined as "relevant comonomer content") thus represents the weight percentage of the total mass of comonomer present in all chains with an overall size Log10Mw between 5.00 and 5.50 compared to the total mass of the polymer composition. The polymer composition may comprise a relevant comonomer content of 0.6 wt% or greater, or 0.8 wt% or greater, or 1.0 wt% or greater, or 1.2 wt% or greater, or 1.4 wt% or greater, or 1.6 wt% or greater, or 1.8 wt% or greater, or 2.0 wt% or greater, or 2.2 wt% or greater, or 2.4 wt% or greater, or 2.6 wt% or greater, or 2.8 wt% or greater, or 3.0 wt% or greater, or 3.2 wt% or greater. In other words, the molecular weight as measured by GPC is between 10 5 g / mol to 10 5.5 The total comonomer contained within the g / mol range fraction is at least 0.6 weight percent, based on the total weight of the polymer composition.

[0058] Mechanical properties

[0059] As described in more detail below, the polymer composition can exhibit a retained tensile elongation at break after aging of greater than 75%. For example, the polymer composition can have a retained elongation at break of 76% or greater, or 80% or greater, or 85% or greater, or 90% or greater, or 95% or greater, or 100% or greater, while at the same time being 105% or less, or 100% or less, or 95% or less, or 90% or less, or 85% or less, or 80% or less.

[0060] As explained in more detail below, the polymer composition can exhibit an ESCR of greater than 400 hours. For example, the polymer composition can exhibit an ESCR of 400 hours or greater, or 450 hours or greater, or 500 hours or greater, or 600 hours or greater, or 700 hours or greater, or 800 hours or greater, or 900 hours or greater, or 1000 hours or greater, or 1100 hours or greater, or 1200 hours or greater, or 1300 hours or greater, or 1400 hours or greater, or 1500 hours or greater, or 1600 hours or greater, or 1700 hours or greater, or 1800 hours or greater, or 1900 hours or greater. or less, while at the same time having an ESCR of 2000 hours or less, or 1900 hours or less, or 1800 hours or less, or 1700 hours or less, or 1600 hours or less, or 1500 hours or less, or 1400 hours or less, or 1300 hours or less, or 1200 hours or less, or 1100 hours or less, or 1000 hours or less, or 900 hours or less, or 800 hours or less, or 700 hours or less, or 600 hours or less, or 500 hours or less, or 450 hours or less.

[0061] As explained in more detail below, the polymer composition can exhibit a cyclic temperature shrinkage of less than 2.50%. For example, the cyclic temperature shrinkage of the polymer composition can be 2.45% or less, or 2.40% or less, or 2.35% or less, or 2.30% or less, or 2.25% or less, or 2.20% or less, or 2.15% or less, or 2.10% or less, or 2.05% or less, or 2.00% or less, or 1.95% or less, or 1.90% or less, or 1.85% or less, or 1.80% or less, or 1.75% or less, or 1.70% or less, or 1.65% or less, or 1.60% or less, or 1.8 .55% or less, while at the same time 1.50% or more, or 1.55% or more, or 1.60% or more, or 1.65% or more, or 1.70% or more, or 1.75% or more, or 1.80% or more, or 1.85% or more, or 1.90% or more, or 1.95% or more, or 2.00% or more, or 2.05% or more, or 2.10% or more, or 2.15% or more, or 2.20% or more, or 2.25% or more, or 2.30% or more, or 2.35% or more, or 2.40% or more.

[0062] additive

[0063] The polymer composition may include additional additives in the form of antioxidants, processing aids, coupling agents, UV stabilizers (including UV absorbers), antistatic agents, carbon black, additional nucleating agents, slip agents, lubricants, viscosity control agents, tackifiers, antiblocking agents, surfactants, extender oils, acid scavengers, flame retardants, and metal deactivators. The polymer composition may include 0.01% to 5% by weight of one or more additional additives. The additives may be added individually as pure components, in combination, and / or in one or more masterbatches.

[0064] The polymer composition contains one or more hindered amine light stabilizers. HALS are chemical compounds containing amine functional groups that are used as stabilizers in plastics and polymers. These compounds can be derivatives of tetramethylpiperidine and are primarily used to protect polymers from free radical oxidation due to exposure to UV light. HALS can include one or more of the following: poly (4-hydroxy-2,2,6,6-tetramethyl-1-piperidinethanol-alt-1,4-butanedioic acid) (CAS# 65447-77-0); bis (2,2,6,6-tetramethyl-4-piperidinyl) sebacate (CAS# 52829-07-9); di-(1,2,2,6,6-pentamethyl-4-piperidinyl)-2-butyl-2-(3,5-di-tert-butyl-4-piperidinyl)-2-ol hydroxybenzyl) malonate (CAS#63843-89-0); bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate (CAS#129757-67-1); poly[[6-[(1,1,3,3-tetramethylbutyl)amino]-s-triazine-2,4-diyl]-[(2,2,6,6-tetramethyl-4-piperidinyl)imino]-hexamethylene-[(2,2,6,6-tetramethyl- 4-piperidinyl)imino] (CAS# 71878-19-8); 1,3,5-triazine-2,4,6-triamine, N,N″′-1,2-ethanediylbis[N-[3-[[4,6-bis[butyl(1,2,2,6,6-pentamethyl-4-piperidinyl)amino]-1,3,5-triazin-2-yl]amino]propyl]-N′,N′′-dibutyl-N′,N′′-bis(1,2,2,6,6-pentamethyl-4-piperidinyl)imino] -piperidinyl)-(CAS#106990-43-6); 1,6-hexanediamine, N,N'-bis(2,2,6,6-tetramethyl-4-piperidinyl)-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-1-butylamine and N-butyl-2,2,6,6-tetramethyl-4-piperidinamine (CAS#192268-64-7). Examples of HALS are available under the trade name TINUVIN TM 622 and CHIMASSORB TM944 is commercially available from BASF, Ludwigshafen, Germany. The polymer composition may comprise 0.1 wt% to 1.0 wt% of the HALS, based on the total weight of the polymer composition. For example, the polymer composition may comprise 0.1 wt% or more, or 0.2 wt% or more, or 0.3 wt% or more, or 0.4 wt% or more, or 0.5 wt% or more, or 0.6 wt% or more, or 0.7 wt% or more, or 0.8 wt% or more, or 0.9 wt% or more, while at the same time comprising 1.0 wt% or less, or 0.9 wt% or less, or 0.8 wt% or less, or 0.7 wt% or less, or 0.6 wt% or less, or 0.5 wt% or less, or 0.4 wt% or less, or 0.3 wt% or less, or 0.2 wt% or less of the HALS, based on the total weight of the polymer composition.

[0065] The polymer composition can include one or more particulate fillers, such as glass fiber or various mineral fillers, including nanocomposites. Fillers, especially those with elongated or flaky particles providing a higher aspect ratio (length / thickness), can improve modulus and post-extrusion shrinkage characteristics. One or more fillers can have a median size or d50 less than 20 μm, less than 10 μm or less than 5 μm. The filler can be surface treated to promote wetting or dispersion in the polymer composition. The specific example of suitable fillers includes but is not limited to calcium carbonate, silicon dioxide, quartz, fused quartz, talc, mica, clay, kaolin, wollastonite, feldspar, aluminum hydroxide and graphite. The filler can be included in the polymer composition in an amount within the range of 2 wt % to 30 wt % or 5 wt % to 30 wt % based on the gross weight of the polymer composition.

[0066] Processing aids may include fluororesins such as metal salts of polytetrafluoroethylene or fluorinated ethylene propylene; carboxylic acids such as zinc stearate or calcium stearate; fatty acids such as stearic acid, oleic acid or erucic acid; fatty amides such as stearamide, oleamide, erucamide or N,N′-ethylenebisstearamide; polyethylene wax; oxidized polyethylene wax; polymers of ethylene oxide; copolymers of ethylene oxide and propylene oxide; vegetable waxes; petroleum waxes; nonionic surfactants; silicone fluids and polysiloxanes.

[0067] Antioxidants may include hindered phenols such as tetrakis[methylene(3,5-di-tert-butyl-4-hydroxyhydro-cinnamate)]methane; bis[(β-(3,5-di-tert-butyl-4-hydroxybenzyl)methylcarboxyethyl)]-sulfide, 4,4′-thiobis(2-methyl-6-tert-butylphenol), 4,4′-thiobis(2-tert-butyl-5-methylphenol), 2,2′-thiobis(4-methyl-6-tert-butylphenol) and thiodiethylenebis(3,5-di-tert-butyl-4-hydroxy)-hydrocinnamate; phosphites and phosphonites, Such as tris (2,4-di-tert-butylphenyl) phosphite and di-tert-butylphenyl-phosphite; thio compounds, such as dilauryl thiodipropionate, dimyristyl thiodipropionate and distearyl thiodipropionate; various siloxanes; polymeric 2,2,4-trimethyl-1,2-didihydroquinoline, n,n'-bis (1,4-dimethylpentyl-p-phenylenediamine), alkylated diphenylamine, 4,4'-bis (α, α-dimethylbenzyl) diphenylamine, diphenyl-p-phenylenediamine, mixed diaryl-p-phenylenediamines and other hindered amine antidegradants or stabilizers.

[0068] Compounding and coating conductor formation

[0069] The component of polymer composition can be added in batches or continuous mixer to form the composition of melt blending.Can add component in any order or first prepare one or more masterbatches to blend with other components.Melt blending can be carried out at a temperature higher than the melting point of the highest molten polymer.Then the melt blended composition can be transported in an extruder or injection molding machine, or be formed into required goods through a mold, or be converted into pellet, adhesive tape, bar or film or some other forms to be used for storage or preparation and supply to the material of next shaping or processing step.Optionally, if shaped as pellet or some similar configurations, pellet etc. can be coated with a release agent so that the processing when storage.

[0070] Examples of compounding equipment include internal batch mixers such as the BANBURY TM or BOLLING TM Internal mixer. Alternatively, a continuous single screw or twin screw mixer such as a FARRELL TM Continuous mixer, WERNER TM and PFLEIDERER TM Twin screw mixer or BUSS TM Kneading Continuous Extruder. The type of mixer utilized and the operating conditions of the mixer will affect the properties of the composition, such as viscosity, volume resistivity and extruded surface smoothness.

[0071] A coated conductor can be made from a polymer composition. The coated conductor includes a conductor and a coating. The coating comprises a polymer composition. The polymer composition is at least partially disposed around the conductor to produce the coated conductor. The conductor can include a conductive metal or an optically transparent structure.

[0072] A method for preparing a coated conductor includes mixing and heating a polymer composition in an extruder to at least the melting temperature of the polymer components to form a polymer melt blend, and then applying the polymer melt blend to a conductor. The term "onto" includes direct or indirect contact between the polymer melt blend and the conductor. The polymer melt blend is in an extrudable state.

[0073] The polymer composition is disposed on and / or around the conductor to form a coating. The coating may be one or more inner layers, such as an insulating layer. The coating may completely or partially cover or otherwise surround or encase the conductor. The coating may be the sole component surrounding the conductor. Alternatively, the coating may be a layer of a multi-layer jacket or sheath surrounding the conductor. The coating may directly contact the conductor. The coating may directly contact the insulating layer surrounding the conductor.

[0074] Example

[0075] Material

[0076] The following materials were used in the following examples.

[0077] The copolymer has a density of 0.955 g / cc, a melt index (I2) of 1.5 g / 10 min. and a melt index (I 21 ) is an ethylene-hexene copolymer of 106 g / 10 min. and is available from The Dow Chemical Company, Midland, MI.

[0078] EP1 has a density of 0.920 g / cc, a melt index (I2) of 0.56 g / 10 min. and a melt index (I 21 ) is 56g / 10min. UNIPOL TM Gas phase unimodal ethylene-butene polymers.

[0079] EP2 has a density of 0.904 g / cc, a melt index (I2) of 0.85 g / 10 min. and a melt index (I 21 ) is 24g / 10min. UNIPOL TM Gas-phase unimodal ethylene-butene polymer (plastomer).

[0080] EP3 is an ethylene-butene polymer (elastomer) having a density of 0.874 g / cc and a melt index (I2) of 0.8 g / 10 min. and is available from The Dow Chemical Company, Midland, Michigan.

[0081] EP4 is an ethylene-octene polymer having a density of 0.94 g / cc and a melt index (I2) of 0.85 g / 10 min. and is available from The Dow Chemical Company, Midland, Michigan.

[0082] CBMB is a carbon black masterbatch containing 45 wt% carbon black and is available from The Dow Chemical Company, Midland, Michigan.

[0083] PEG is polyethylene glycol with a weight average molecular weight of 20,000 g / mol and is available from Clariant, Germany.

[0084] AO1 is 4,4'-thiobis(2-tert-butyl-5-methylphenol), available under the trade name LOWINOX TM TBM-6 is commercially available and can be obtained from Addivant, Danbury, CT.

[0085] AO2 is a sterically hindered phenolic antioxidant with the chemical name of pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, which can be IRGANOX 1010 TM Commercially available from BASF, Ludwigshafen, Germany.

[0086] AO3 is a hydrolysis-stable phosphite processing stabilizer with the chemical name tris(2,4-di-tert-butylphenyl) phosphite. 168 was purchased commercially from BASF, Ludwigshafen, Germany.

[0087] PA is a trade name DYNAMAR TM FX 5912 is a fluororesin processing aid commercially available from 3M, Saint Paul, Minnesota, USA.

[0088] Sample preparation

[0089] Inventive Examples ("IE") 1-6 and Comparative Examples ("CE") 1-5 were compounded on a small BANBURY (1.2 kg) or BANBURY (12 kg) batch mixer from HF Mixing Group. The drop temperature was 150°C. After compounding, the samples were extruded and pelletized. CE4 is a pre-compounded and pelletized sample.

[0090] The pelletized samples are formed into plates and jackets for different mechanical tests. Plates are prepared by compression molding pellets on a preheated arbor press at 180°C. Pellets are placed in molds of different thicknesses according to test requirements. The sample is heated to 180°C for 4 minutes, then pressed at 3.45 MPa for 3 minutes, and then pressed at 17.24 MPa for 3 minutes. The sample is cooled to 23°C at 15°C / minute in the press and then taken out. A jacket sample with a wall thickness of 0.05cm is prepared by extruding the polymer composition onto a conductor at 91 meters / minute using a 6.35cm wire extrusion line from Davis-Standard at 180°C-240°C. The conductor is taken out and the jacket sample is conditioned at room temperature for 24 hours before the tensile test.

[0091] The samples were heat aged to obtain tensile elongation at break by preheating a Type I oven (according to ASTM D5423) to 100°C. The samples were then loaded into the preheated oven and aged for 10 days. After aging, the samples were then conditioned at 23°C, 50% relative humidity for 24 hours.

[0092] Test Method

[0093] Triple detector gel permeation chromatography (GPC) was performed using a chromatographic system. The chromatographic system consisted of a PolymerChar GPC-IR (Valencia, Spain) high temperature GPC chromatograph equipped with an internal IR5 infrared detector (IR5) and a 4-capillary viscometer (DV) connected to an Agilent Technologies 2-angle laser light scattering (LS) detector model 2040. For all light scattering measurements, a 15-degree angle was used for measurement purposes. The autosampler oven chamber was set to 160 degrees Celsius, and the column chamber was set to 150 degrees Celsius. The columns used were 4 Agilent "MixedA" 30 cm 20 micron linear mixed bed columns. The chromatographic solvent used was 1,2,4 trichlorobenzene and contained 200 ppm of butylated hydroxytoluene (BHT). The solvent source was nitrogen sparged. The injection volume used was 200 microliters, and the flow rate was 1.0 ml / min.

[0094] Calibration and calculation of conventional molecular weight moments and distributions were performed according to the methods described in the conventional GPC procedures (using a 20 um "Mixed A" column).

[0095] The systematic method for determining the multi-detector offset was performed in a manner consistent with that published by Balke, Mourey et al. (Mourey and Balke, Chromatography Polym., Chapter 12, (1992)) (Balke, Thitiratsakul, Lew, Cheung, Mourey, Chromatography Polym., Chapter 13, (1992)) using the PolymerChar GPCOne TM The software optimizes the triple detector logarithmic (MW and IV) results from a broad homopolymer polyethylene standard (Mw / Mn>3) with the narrow standards column calibration results from the narrow standards calibration curve.As used herein, "MW" refers to molecular weight.

[0096] Absolute molecular weight data were obtained using PolymerChar GPCOne TM The software was developed in a manner consistent with that published by Zimm (Zimm, BH, Journal of Physical Chemistry, 16, 1099 (1948)) and Kratochvil (Kratochvil, P., Classical Light Scattering from Polymer Solutions, Elsevier, Oxford, NY (1987)). The total injected concentration used to determine the molecular weight was obtained from the mass detector area and the mass detector constant, which was derived from a suitable linear polyethylene homopolymer or one of the polyethylene standards of known weight average molecular weight. The calculated molecular weight (using GPCOne TM ) are obtained using the light scattering constants from one or more polyethylene standards mentioned below and a refractive index concentration coefficient dn / dc of 0.104. Typically, the mass detector response (IR5) and the light scattering constant (using GPCOne TM Viscometer calibration (using GPCOne TMThe viscometer constant (measured using GPCOne) can be calculated using the method described by the manufacturer or, alternatively, by using the published value of a suitable linear standard such as Standard Reference Material (SRM) 1475a (available from the National Institute of Standards and Technology, NIST). TM Obtained), which relates the specific viscosity area (DV) and injected mass used for the calibration standard to its intrinsic viscosity (IV). The chromatographic concentration was assumed to be low enough to eliminate the effect of resolving the second viral coefficient (the effect of concentration on molecular weight).

[0097] The absolute weight average molecular weight (Mw(Abs)) is calculated by dividing the light scattering (LS) integrated chromatogram (determined by the light scattering constant) by the mass recovered from the mass constant and mass detector (IR5) area (using GPCOne TM The molecular weight and intrinsic viscosity responses were extrapolated at the end of the chromatogram where the signal-to-noise ratio was low (using GPCOne TM ). Other corresponding moments Mn (Abs) and Mz (Abs) The calculation according to equation 1-2 is as follows:

[0098]

[0099]

[0100] Conventional GPC: The chromatography system consisted of a PolymerChar GPC-IR (Valencia, Spain) high temperature GPC chromatograph equipped with an internal IR5 infrared detector (IR5) coupled to a Precision Detectors (now Agilent Technologies) 2-angle laser light scattering (LS) detector model 2040. For all light scattering measurements, a 15 degree angle was used for measurement purposes. The autosampler oven chamber was set to 160 degrees Celsius, and the column chamber was set to 150 degrees Celsius. The columns used were four Agilent "MixedA" 30 cm 20 micron linear mixed bed columns. The chromatographic solvent used was 1,2,4 trichlorobenzene containing 200 ppm of butylated hydroxytoluene (BHT). The solvent source was nitrogen sparged. The injection volume used was 200 microliters, and the flow rate was 1.0 ml / min.

[0101] Calibration of the GPC column set was performed using 21 narrow molecular weight distribution polystyrene standards with molecular weights ranging from 580 g / mol to 8,400,000 g / mol and arranged in the form of 6 "cocktail" mixtures with at least ten times the spacing between individual molecular weights. Standards were purchased from Agilent Technologies. For molecular weights equal to or greater than 1,000,000 g / mol, polystyrene standards were prepared at 0.025 g in 50 ml of solvent, and for molecular weights less than 1,000,000 g / mol, polystyrene standards were prepared at 0.05 g in 50 ml of solvent. The polystyrene standards were dissolved at 80 degrees Celsius and gently stirred for 30 minutes. The polystyrene standard peak molecular weight was converted to polyethylene molecular weight using equation 1 (as described by Williams and Ward, J. Polym. Sci., Polym. Let., 6, 621 (1968)):

[0102] MW 聚乙烯 =A×(Mw 聚苯乙烯 ) B (Equation 3)

[0103] Where MW is the molecular weight, the value of A is 0.4315 and B is equal to 1.0.

[0104] A fifth order polynomial was used to fit the calibration points to the corresponding polyethylene equivalents.Small adjustments to A (approximately 0.395 to 0.440) were made to correct for column resolution and band broadening effects, resulting in a linear homopolymer polyethylene standard at 120,000 g / mol Mw.

[0105] Total plate counts were performed on the GPC column set using decane (prepared as 0.04 g in 50 ml TCB). Plate counts (Equation 4) and symmetry (Equation 5) were measured at 200 μl injections according to the following equations:

[0106]

[0107] where RV is the retention volume in milliliters, peak width is in milliliters, peak maximum is the maximum height of the peak, and 1 / 2 height is the height of 1 / 2 the peak maximum.

[0108]

[0109] Where RV is the retention volume in milliliters, and peak width is in milliliters, peak maximum is the maximum position of the peak, tenth height is 1 / 10 the height of the peak maximum, and where post-peak is the tail of the peak with a retention volume later than the peak maximum, and where front-peak is the front of the peak 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.

[0110] The samples were prepared semi-automatically using PolymerChar "Instrument Control" software, with a target sample weight of 2 mg / mL and solvent (containing 200 ppm BHT) added to a septum-capped vial previously sparged with nitrogen via a PolymerChar high-temperature autosampler. The samples were dissolved at 160 degrees Celsius for 2 hours with "low speed" shaking.

[0111] Based on the GPC results using the internal IR5 detector (measurement channel) of the PolymerChar GPC-IR spectrometer according to Equations 6-8, the TM Calculations of Mn(conv), Mw(conv), and Mz(conv) were performed using the IR software, the baseline-subtracted IR chromatogram at each equally spaced data collection point (i), and the polyethylene equivalent molecular weight obtained from the narrow standard calibration curve at point (i) according to Equation 1.

[0112]

[0113]

[0114]

[0115] To monitor the deviation over time, a flow rate marker (decane) was introduced into each sample via a micropump controlled by the PolymerChar GPC-IR system. This flow rate marker (FM) was used to linearly correct the pump flow rate for each sample (Flow Rate (Nominal)) by comparing the RV of the corresponding decane peak in the sample (RV (FM Sample)) with the RV of the decane peak in the narrow standard calibration (RV (FM Calibrated)). It was then assumed that any change in the decane marker peak time was related to a linear change in flow rate (Flow Rate (Effective)) throughout the run. To facilitate the highest accuracy in the RV measurement of the flow marker peak, a least squares fitting procedure was used to fit the peak of the flow marker concentration chromatogram to a quadratic equation. The first derivative of the quadratic equation was then used to solve for the true peak position. After calibrating the system based on the flow marker peak, the effective flow rate (relative to the narrow standard calibration) was calculated as Equation 9. by PolymerChar GPCOne TM The software completes the processing of the flow marker peaks.An acceptable flow rate correction is such that the effective flow rate should be within + / - 2% of the nominal flow rate.

[0116] Flow rate (effective) = flow rate (nominal) × (RV (FM calibration) / RV (FM sample)) (Equation 9)

[0117] Using known short chain branching (SCB) frequencies (e.g., by 13 The IR5 detector was calibrated for quantitative analysis using at least ten vinyl polymer standards (polyethylene homopolymer and ethylene / octene copolymer) with short chain branching frequencies ranging from 0 SCB / 1000 total C for the homopolymer to approximately 40 SCB / 1000 total C, where total C = carbon in the backbone + carbon in the branches. Each standard had a weight average molecular weight of 36,000 to 126,000 g / mole, as determined by the GPC-LALS processing method described above. Each standard had a molecular weight distribution (Mw / Mn) of 2.0 to 2.5, as determined by the GPC-LALS processing method described above.

[0118] For each of the "SCB" standards, the "IR5 Area Ratio" (or "IR5 Methyl Channel Area / IR5 Measurement Channel Area") was calculated as the "Baseline-Subtracted Area Response of the IR5 Methyl Channel Sensor" to the "Baseline-Subtracted Area Response of the IR5 Measurement Channel Sensor" (as included as part of the GPC-IR instrument via the standard filter and filter wheel supplied by PolymerChar: Part No. IR5_FWM01). A linear fit of the SCB frequency to the "IR5 Area Ratio" was constructed in the form of Equation 10:

[0119] SCB / 1000 total C = A0 + [A1 x (IR5 methyl channel area / IR5 measurement channel area)] (Equation 10)

[0120] In Equation 10, A0 is the intercept of "SCB / 1000 total C" at "IR5 area ratio" of zero, and A1 is the slope of "SCB / 1000 total C" with respect to "IR5 area ratio" and represents the increase of SCB / 1000 total C as "IR5 area ratio" changes.

[0121] A "series of linear, baseline-subtracted chromatogram heights" of the chromatogram produced by the "IR5 methyl channel sensor" was established as a function of the column elution volume to produce a baseline-corrected chromatogram (methyl channel). A "series of linear, baseline-subtracted chromatogram heights" of the chromatogram produced by the "IR5 measurement channel" was established as a function of the column elution volume to produce a baseline-corrected chromatogram (measurement channel).

[0122] At each column elution volume index (each equally spaced index represents 1 data point per second at 1 ml / min elution) at both ends of the sample integration limit, the "IR5 Height Ratio" of the "Baseline Corrected Chromatogram (Methyl Channel)" to the "Baseline Corrected Chromatogram (Measurement Channel)" is calculated. The "IR5 Height Ratio" is multiplied by the factor A1, and the factor A0 is added to this result to produce the predicted SCB frequency for the sample. The result is converted to comonomer mole percentage in Equation 11 as follows:

[0123]

[0124] In Equation 11, "SCB f " is "SCB per 1000 total C", and "comonomer length" = 8.

[0125] The mole % comonomer is then converted to weight % comonomer by using the molecular weights of octene and ethylene.

[0126] By the above method, the weight percent comonomer of a sample or any portion of a sample can be calculated. The use of this technique in combination with conventional GPC analysis allows the weight percent comonomer to be determined as a function of molecular weight (C8 i ).

[0127] The high Mw weight fraction is determined by the conventional GPC method described above.The high Mw weight fraction is the total mass fraction having a Log10 Mw of at least 5.00 and less than 5.50 based on conventional GPC, as shown in Equation 12.

[0128]

[0129] The high Mw comonomer content is calculated by using the weight average comonomer wt% reported within these molecular weight ranges, as shown in Equation 13.

[0130]

[0131] The product of the high Mw weight fraction and the high Mw comonomer content is the weight fraction of the resin that consists of the comonomer included in the polymer chain of a specific molecular weight. This product is the relevant comonomer.

[0132] The elongation at break was measured using an extensometer according to IEC 60811-501 on plate samples at 25 mm / min.

[0133] Density was measured at 23°C according to ASTM D792.

[0134] According to ASTM D1238 at 190 ° C with a specified 2.16 kg (I2) load or 21.6 kg load (I 21 ) to measure the melt index.

[0135] ESCR was measured according to IEC 60811-406 (2012) Method B without oven conditioning the test sample. A 52 g sample was placed in a frame measuring 150 mm x 180 mm x 1.9 mm. An initial force of <1 kilonewton ("kN") was applied at 170°C. A force of 200 kN was then applied for 2 minutes while the sample was held at 170°C. After 2 minutes, a cooling box was placed in the press and the temperature was lowered to 40°C.

[0136] Cyclic temperature retraction testing is performed on jacket samples. Cyclic temperature retraction is performed by conditioning the jacket samples in an oven from 40°C to 100°C at a ramp rate of 0.5°C / min. The sample is held at 100°C for 60 minutes, then the temperature is reduced back to 40°C at a rate of 0.5°C / min. The jacket is held at 40°C for 20 minutes, and then the temperature cycle is repeated 4 more times for a total of 5 cycles. Shrinkage is reported as the percentage change in jacket length from before to after the test and is measured on a 61 cm long specimen using a ruler accurate to 1.6 mm.

[0137] result

[0138] Table 1 provides combined data for IE1-IE6 and CE1-CE4. Table 2 provides mechanical testing results and target values ​​for mechanical properties for IE1-IE6 and CE1-CE4. The tensile elongation at break is provided for unaged ("TE") and heat-aged samples ("Aged TE"). The retained elongation at break after aging ("Retained TE") is calculated by dividing the Aged TE value by the TE value of the sample. The entry "nm" indicates that the particular property was not measured.

[0139] Table 1

[0140]

[0141] *Calculated by interpolation from IE1 and CE4

[0142] Table 2

[0143]

[0144] Referring now to Tables 1 and 2, IE1-IE6 were able to exceed the target values ​​for each mechanical property, while CE1-CE4 all failed to meet at least one of the target mechanical property values. IE1-IE6 demonstrate that various ethylene-based polymers at various concentrations can meet mechanical property targets, as long as the high-Mw comonomer content is 3.2 wt% or greater, based on the total weight of the combined copolymer and ethylene-based polymer, and the related comonomer content is 0.6 wt% or greater. CE1 demonstrates that, despite having the same ingredients and similar concentrations as IE1, IE4, and IE5, the related comonomer content is below 0.6 wt% and, therefore, fails to meet the ESCR target. CE2 demonstrates that the incorporation of polyethylene glycol can help achieve the ESCR target. CE3 and CE4 each demonstrate that a high-Mw comonomer content below 3.2 wt% fails to produce a sample that meets each of the target mechanical property values. Furthermore, CE3 and CE4 each demonstrate that a related comonomer content below 0.6 wt% fails to produce a sample that meets each of the target mechanical property values.

Claims

1. A polymer composition comprising: (i) a copolymer of ethylene and an alpha-olefin comonomer, said copolymer having a density from 0.945 g / cc to 0.960 g / cc; (ii) vinyl polymers; and (iii) polyethylene glycol, The combination of (i) and (ii) is 10 5 g / mol to 10 5.5 g / mol weight average molecular weight range having a high Mw comonomer content of 3.2 wt% or more based on the total weight of (i) and (ii) combined, wherein 15 wt% or more of the total weight of the polymer composition is a polymer having a relative humidity of 10 % as measured by GPC. 5 g / mol to 10 5.5 said combination of (i) and (ii) having a molecular weight in the range of g / mol, wherein the polymer composition has a relevant comonomer content of 0.6 wt% or greater, and wherein the polymer composition has a density of 0.945 g / cc or greater as measured according to ASTM D792.

2. The polymer composition of claim 1, wherein the polymer composition comprises 35 to 85 wt% of the copolymer, based on the total weight of the polymer composition.

3. The polymer composition of claim 1, wherein the polymer composition comprises 0.5 wt% to 1 wt% of the polyethylene glycol, based on the total weight of the polymer composition.

4. The polymeric composition of claim 1 , wherein the polymeric composition comprises 15 to 30 weight percent of the ethylene-based polymer, based on the total weight of the polymeric composition, and the ethylene-based polymer is a linear low density polyethylene having a density of 0.91 to 0.93 g / cc as measured according to ASTM D792.

5. The polymer composition of claim 1 , wherein the polymer composition comprises 15 to 19 weight percent of the ethylene-based polymer, based on the total weight of the polymer composition, and the ethylene-based polymer is a plastomer having a density of 0.90 to 0.91 g / cc as measured according to ASTM D792.

6. The polymer composition of claim 1 , wherein the polymer composition comprises 45 to 55 weight percent of the ethylene-based polymer, based on the total weight of the polymer composition, and the ethylene-based polymer is a high density polyethylene having a density of 0.93 to 0.95 g / cc as measured according to ASTM D792.

7. The polymer composition of claim 1 , wherein the polymer composition comprises 10 to 15 weight percent of the ethylene-based polymer, based on the total weight of the polymer composition, and the ethylene-based polymer is an elastomer having a density of 0.80 to 0.90 g / cc as measured according to ASTM D792.

8. The polymer composition of claim 1, wherein the combination of (i) and (ii) is 10 5 g / mol to 10 5.5 The invention can be used in the molecular weight range of 1000 g / mol with a high Mw comonomer content of 12.0 wt% or less.

9. The polymer composition of claim 1, wherein 30 wt% or less of the total weight of the polymer composition is a polymer having a 10 5 g / mol to 10 5.5 The combinations of (i) and (ii) having a molecular weight in the g / mol range.

10. A coated conductor, comprising: conductor; as well as The polymer composition of any one of claims 1 to 9, wherein the polymer composition is at least partially disposed around the conductor.

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