Polymer processing aids based on polymeric phosphites, polydimethylsiloxanes and polyalkylene glycols

Abstract

Embodiments of formulations, such as polymeric processing aid formulations, can include at least 95% by weight of an ethylene-based polymer, a polymeric phosphite, a substituted polydimethylsiloxane (PDMS), and at least 500 ppmw of a polyalkylene glycol.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the benefit and priority of U.S. Application No. 63 / 481,309, filed on January 24, 2023, the entire content of which is incorporated herein by reference. Technical Field

[0003] The present disclosure generally relates to formulations comprising ethylene - based polymers, and more particularly to formulations comprising ethylene - based polymers and processing aid materials such as polymeric phosphites, substituted polydimethylsiloxanes, and polyalkylene glycols. Background Art

[0004] Plastics are used in a wide range of industrial applications, including packaging, construction, and wires and cables. However, many plastics suffer from melt fracture during extrusion, which is a phenomenon in which the plastic surface is distorted due to fluctuations or irregularities. Some types of melt fracture, such as shark - skin melt fracture, affect the surface of the plastic by causing an irregular and sometimes scaly surface texture, which may reduce the gloss of the surface.

[0005] Conventional methods for preventing melt fracture in polyethylene include using fluoropolymer - based processing aids. However, concerns that fluorinated compounds may be persistent in the environment have led to restrictions on these materials, including fluoropolymer - based processing aids. Thus, there is a need for improved formulations that can reduce melt fracture while also alleviating concerns about environmental persistence. Summary of the Invention

[0006] Embodiments of the present disclosure address these problems with formulations comprising an ethylene - based polymer, a polymeric phosphite, a substituted polydimethylsiloxane, and a polyalkylene glycol. As described herein, the formulations may comprise at least 95 weight percent (wt.%) of an ethylene - based polymer. The formulations may also comprise at least 500 parts per million by weight (ppmw) of a polyalkylene glycol. Without being bound by theory, the polymeric phosphite, polydimethylsiloxane, and polyalkylene glycol act in combination as processing aids to reduce melt fracture.

[0007] According to one or more embodiments of the present disclosure, articles can be produced from the above - described formulations.

[0008] Additional features and advantages will be set forth in the detailed description which follows, and in part will be obvious to those skilled in the art from that description or recognized by practice of the embodiments described herein, including the detailed description which follows other than the claims.

[0009] It should be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and characteristics of the claimed subject matter. Detailed Description

[0010] Embodiments of formulations (such as polymer processing aid formulations comprising ethylene-based polymers, polymeric phosphites, substituted polydimethylsiloxanes, and polyalkylene glycols) will now be described in detail. In many of the embodiments described herein, the polymeric phosphites, substituted polydimethylsiloxanes (PDMS), and polyalkylene glycols can be considered together as processing aids. Additional additives may also be included; however, the formulations are substantially free of fluoropolymers.

[0011] Without being bound by theory, the polymeric phosphites, polyalkylene glycols, and substituted PDMS can interact with the metal surfaces of an extruder and with each other such that a lubricating multi-layer is formed between the metal surfaces and the polyethylene melt, thereby reducing melt fracture.

[0012] As used herein, the term "polymer" can refer to a polymeric compound prepared by polymerizing the same or different types of monomers. Thus, the general term polymer encompasses the term "homopolymer", which is commonly used to refer to a polymer prepared from only one type of monomer; and "copolymer", which refers to a polymer prepared from two or more different monomers. As used herein, the term "interpolymer" refers to a polymer prepared by polymerizing at least two different types of monomers. Thus, the general term interpolymer includes copolymers and polymers prepared from more than two different types of monomers (such as terpolymers).

[0013] The terms "blend", "polymer blend", etc. mean 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 methods known in the art. A blend is not a laminate, but one or more layers of a laminate may contain a blend. Such blends can be prepared as dry blends, formed in situ (e.g., in a reactor), melt blends, or using other techniques known to those skilled in the art.

[0014] As used in this disclosure, the term "polyethylene" or "ethylene-based polymer" can refer to a polymer that contains greater than 50 mole % of units derived from ethylene monomers. This includes polyethylene homopolymers or copolymers (meaning units derived from two or more comonomers). Common forms of ethylene-based polymers known in the art include low density polyethylene (LDPE); linear low density polyethylene (LLDPE); ultra low density polyethylene (ULDPE); very low density polyethylene (VLDPE); single-site catalyzed linear low density polyethylene, including both linear and substantially linear low density resins (m-LLDPE); medium density polyethylene (MDPE); and high density polyethylene (HDPE).

[0015] The term "LLDPE" includes two resins made using conventional Ziegler-Natta catalyst systems, chromium-based catalyst systems, and single-site catalysts (including but not limited to bis-metallocene catalysts (sometimes referred to as "m-LLDPE"), constrained geometry catalysts (CGC), and molecular catalysts). The resins include linear, substantially linear, or heterophasic polyethylene copolymers or homopolymers. Compared to LDPE, LLDPE contains less long chain branching and includes substantially linear ethylene polymers, which are further defined in U.S. Patent No. 5,272,236, U.S. Patent No. 5,278,272, U.S. Patent No. 5,582,923, and U.S. Patent No. 5,733,155; homogeneous branched linear ethylene polymer compositions, such as those in U.S. Patent No. 3,645,992; heterogeneous branched ethylene polymers, such as those prepared according to the process disclosed in U.S. Patent No. 4,076,698; and / or blends thereof (such as those disclosed in US 3,914,342 or US 5,854,045). LLDPE can be made by gas phase, solution phase, or slurry polymerization or any combination thereof, using any type of reactor or reactor configuration known in the art.

[0016] As used herein, "polymeric phosphite" refers to a polymeric compound containing phosphite and is intended to be interpreted broadly to include substances that might be called oligomeric materials. For example, a polymeric phosphite can contain a molecule having at least three, at least four, at least five, or at least six phosphite-containing units. As another example, a polymeric phosphite can contain a molecule having 500 or fewer, 100 or fewer, 90 or fewer, 50 or fewer, 20 or fewer, 5 to 500, 5 to 100, 5 to 15, or 3 to 20 phosphite-containing units.

[0017] As used herein, "fluoropolymer" refers to a polymeric compound containing fluorine and is intended to be construed broadly to include substances that may be referred to as oligomeric materials. For example, a fluoropolymer may include molecules containing at least three, at least four, at least five, or at least six fluorine-containing units. As another example, a polymeric phosphite may contain 500 or fewer, 100 or fewer, 90 or fewer, 50 or fewer, 20 or fewer, 5 to 500, 5 to 100, 5 to 15, or 3 to 20 fluorine-containing units.

[0018] As used herein, "substantially free of" means containing less than 50 ppmw.

[0019] As used herein, "polymer melt" refers to a polymer or polymer blend at a temperature above its glass transition temperature (i.e., below which the physical properties of the polymer change to those of a glassy or crystalline state) and generally above its melting temperature. The polymer melt can exist as a high-viscosity liquid and can have non-Newtonian or viscoelastic properties.

[0020] Various compositions are considered suitable for ethylene-based polymers. In one or more embodiments, the ethylene-based polymer may include linear low-density polyethylene (LLDPE). In an embodiment, the ethylene-based polymer may include a melt index (I2) of 0.5 g / 10 min as measured according to ASTM D-1238 (190 °C / 2.16 Kg). In an embodiment, the ethylene-based polymer may include a melt index of 0.01 g / 10 min to 2.0 g / 10 min, 0.2 g / 10 min to 0.8 g / 10 min, 0.3 g / 10 min to 0.7 g / 10 min, 0.4 g / 10 min to 0.6 g / 10 min, or 0.45 g / 10 min to 0.55 g / 10 min. In a further embodiment, the ethylene-based polymer may include a density of 0.850 g / cc to 0.950 g / cc, 0.875 g / cc to 0.925 g / cc, 0.890 g / cc to 0.915 g / cc, or 0.895 g / cc to 0.910 g / cc.

[0021] In one or more embodiments, the formulation may comprise at least 95 weight percent (wt%) of an ethylene-based polymer. In embodiments, the formulation may comprise at least 90 wt%, at least 91 wt%, at least 92 wt%, at least 93 wt%, at least 94 wt%, at least 95 wt%, at least 96 wt%, at least 97 wt%, at least 98 wt% or at least 99 wt% of an ethylene-based polymer. In embodiments, the formulation may comprise from 90.0 wt% to 99.9 wt%, from 91.0 wt% to 99.9 wt%, from 92.0 wt% to 99.9 wt%, from 93.0 wt% to 99.9 wt%, from 94.0 wt% to 99.9 wt%, from 95.0 wt% to 99.9 wt%, from 95.0 wt% to 99.8 wt%, from 95.0 wt% to 99.5 wt%, from 95.0 wt% to 99.3 wt%, from 95.0 wt% to 99.0 wt%, from 95.0 wt% to 98.5 wt%, from 95.0 wt% to 98.0 wt%, from 95.0 wt% to 97.5 wt%, from 95.0 wt% to 97.0 wt%, from 95.0 wt% to 96.5 wt%, from 95.0 wt% to 96.0 wt% or from 95.0 wt% to 95.5 wt%.

[0022] A variety of compositions are considered suitable for polyalkylene glycols. For example, polyalkylene glycols can include polyethylene glycol, polypropylene glycol, polyisopropylene glycol, and combinations thereof. Examples of suitable polyalkylene glycol derivatives include ethers of polyalkylene glycols, mono- and polycarboxylic acid esters of polyalkylene glycols, and combinations thereof.

[0023] In one or more embodiments, the polyalkylene glycol may include polyethylene glycol (PEG) having an average molecular weight (MW) of from 1,000 grams per mole (g / mol) to 40,000 g / mol. In an embodiment, the PEG may have an average MW of from 1,000 g / mol to 40,000 g / mol, from 2,500 g / mol to 40,000 g / mol, from 5,000 g / mol to 40,000 g / mol, from 7,500 g / mol to 40,000 g / mol, from 10,000 g / mol to 40,000 g / mol, from 20,000 g / mol to 40,000 g / mol, from 1,000 g / mol to 20,000 g / mol, from 2,500 g / mol to 20,000 g / mol, from 5,000 g / mol to 20,000 g / mol, from 7,500 g / mol to 20,000 g / mol, from 10,000 g / mol to 20,000 g / mol, from 1,000 g / mol to 10,000 g / mol, from 2,500 g / mol to 10,000 g / mol, from 5,000 g / mol to 10,000 g / mol, or from 7,500 g / mol to 10,000 g / mol.

[0024] In addition, the formulation may contain at least 500 ppmw of PEG. In an embodiment, the formulation may contain at least 500 ppmw, at least 600 ppmw, at least 700 ppmw, at least 800 ppmw, at least 900 ppmw, or at least 1000 ppmw of PEG. Without being bound by theory, it has surprisingly been found that if a minimum amount of 500 ppmw of PEG is not provided in the formulation, the formulation may fail to clear melt fracture, or may fail to clear melt fracture within 120 minutes or less.

[0025] In one or more embodiments, the polymeric phosphite may be a liquid polymeric phosphite. In an embodiment, the polymeric phosphite may be a liquid polymeric phosphite having the formula (I), wherein R 1 、R 2 、R 3 and R 4 may be the same or different and are independently selected from the group consisting of C 1-20 alkyl, C 2-22 alkenyl, C 6-40 cycloalkyl, C 7-40 subcycloalkyl, and Y—OH serves as the end-capping moiety for R 1 、R 2 、R 3 and R 4 ; Y is selected from the group consisting of C 2-40 alkylene, C 2-40 alicyclic carboxylate, and C3-40 a group consisting of cycloalkyl; x ranges from 12 to 1,000; wherein R 7 and R 9 are independently selected from the group consisting of linear and branched C 1-6 alkylene groups, R 8 is selected from the group consisting of C 5-10 saturated carbocyclic rings, and a and b are independently selected from the group consisting of 0 and 1. In an embodiment, the polymeric phosphite has an average MW of at least 8,000.

[0026]

[0027] In one or more embodiments, the polymeric phosphite can be a liquid polymeric phosphite having the formula (Ia), wherein R 1 、R 2 、R 3 and R 4 can be the same or different and are independently selected from the group consisting of C 1-20 alkyl, C 2-22 alkenyl, C 6-40 cycloalkyl, C 7-40 subcycloalkyl groups, and Y—OH is used as the end-capping moiety for R 1 、R 2 、R 3 and R 4 ; Y is selected from the group consisting of C 2-40 alkylene, C 2-40 alicyclic carboxylate and C 3-40 cycloalkyl groups, and x ranges from 12 to 500. In an embodiment, the polymeric phosphite has an average MW of at least 8,000.

[0028]

[0029] In one or more embodiments, the formulation may comprise from 1000 ppmw to 2000 ppmw of a polymeric phosphite. In an embodiment, the formulation may comprise from 500 ppmw to 10000 ppmw, from 550 ppmw to 9500 ppmw, from 600 ppmw to 9000 ppmw, from 650 ppmw to 8500 ppmw, from 700 ppmw to 8000 ppmw, from 750 ppmw to 7500 ppmw, from 800 ppmw to 7000 ppmw, from 900 ppmw to 6500 ppmw, from 950 ppmw to 6000 ppmw, from 1000 ppmw to 5500 ppmw, from 1000 ppmw to 5000 ppmw, from 1000 ppmw to 4500 ppmw, from 1000 to 4000 ppmw, from 1000 ppmw to 3500 ppmw, from 1000 ppmw to 3000 ppmw, from 1000 ppmw to 2500 ppmw or from 1000 ppmw to 2000 ppmw of a polymeric phosphite.

[0030] "Polydimethylsiloxane" ("PDMS") is a polymeric organosilicon compound having the following general formula (II), where n is the number of repeating monomer [SiO(CH3)2] units and n is greater than or equal to 2, or is from 2 to 20,000:

[0031]

[0032] Although the present disclosure relates to substituted PDMS, it is contemplated that unsubstituted PDMS may also be used in various formulations. "Substituted PDMS" is a PDMS in which at least one methyl group of formula (II) is replaced or substituted by a substituent. Non-limiting examples of substituents include halogen atoms (such as chlorine, fluorine, bromine and iodine); groups containing halogen atoms (such as chloromethyl group, perfluorobutyl group, trifluoroethyl group and nonafluorohexyl group); groups containing an oxygen atom (such as hydroxyl group, alkoxy groups (such as methoxy group and ethoxy group), (meth)acrylic group and carboxyl group); groups containing a nitrogen atom (such as amino functional group, acylamino functional group and cyano functional group); groups containing a sulfur atom (such as mercapto group); hydrogen; C2-C 10 alkyl group (such as ethyl group); C2-C 10 alkynyl group; alkenyl groups (such as vinyl group and allyl group); aryl groups (such as phenyl group and substituted phenyl group); cycloalkyl groups (such as cyclohexyl group); and combinations thereof. The substituted methyl group can be a terminal methyl group or a non-terminal methyl group. Examples of suitable substituted PDMS include trialkylsilyl-capped PDMS, where at least one alkyl is C2-C 10Alkyl; dialkylhydroxysilyl-terminated PDMS; dialkylhydrosilyl-terminated PDMS; dialkylalkenylsilyl-terminated PDMS; and dialkylvinylsilyl-terminated PDMS. In one embodiment, the substituted PDMS is dimethylhydroxysilyl-terminated PDMS. In another embodiment, the substituted PDMS is dimethylvinylsilyl-terminated PDMS.

[0033] In one embodiment, the substituted PDMS does not include a group containing a nitrogen atom. In another embodiment, the substituted PDMS does not include an epoxy-substituted group. In one embodiment, the PDMS is unsubstituted. "Unsubstituted PDMS" is a PDMS of formula (II), wherein the methyl groups in formula (II) are not substituted by substituents. In one embodiment, the unsubstituted PDMS is trimethylsilyl-terminated PDMS.

[0034] In another embodiment, the PDMS may include silanol-terminated PDMS. In one embodiment, the silanol-terminated PDMS may have at least one silanol group at at least one end of the polymeric or oligomeric material. In yet another embodiment, the silanol-terminated PDMS may have silanol groups at both ends of the polymeric or oligomeric material.

[0035] In one or more embodiments, the PDMS may have a kinematic viscosity of at least 1,000 centistokes (cSt) to 100,000 cSt. In an embodiment, the PDMS may have a kinematic viscosity of 100 cSt to 100,000 cSt, 250 cSt to 100,000 cSt, 500 cSt to 100,000 cSt, 750 cSt to 100,000 cSt, 1,000 cSt to 100,000 cSt, 2,500 cSt to 100,000 cSt, 5,000 cSt to 100,000 cSt, 7,500 cSt to 100,000 cSt, 10,000 cSt to 100,000 cSt, 25,000 cSt to 100,000 cSt, 50,000 cSt to 100,000 cSt, 75,000 cSt to 100,000 cSt, 100,000 cSt to 250,000 cSt, or 100,000 cSt to 500,000 cSt.

[0036] In one or more embodiments, the formulation may comprise from 840 ppmw to 1680 ppmw of PDMS. In an embodiment, the formulation may comprise from 500 ppmw to 10000 ppmw, from 550 ppmw to 9000 ppmw, from 600 ppmw to 8000 ppmw, from 650 ppmw to 7000 ppmw, from 700 ppmw to 6000 ppmw, from 750 ppmw to 5000 ppmw, from 800 ppmw to 4000 ppmw, from 800 ppmw to 3000 ppmw, or from 800 ppmw to 2000 ppmw of PDMS.

[0037] In addition, the weight ratio of polyalkylene glycol:PDMS:polymeric phosphite can be from 1:1:1 to 1:1:2 to 1:2:2. In an embodiment, the weight ratio of polyalkylene glycol:PDMS:polymeric phosphite can be from 1:1:1 to 1:1:10, from 1:1:1 to 1:1:5, from 1:1:1 to 1:1:2, from 1:1:1 to 1:10:1, from 1:1:1 to 1:5:1, or from 1:1:1 to 1:2:1.

[0038] In one or more embodiments, the formulation may be substantially free of fluoropolymers. In an embodiment, the formulation may comprise less than 50 ppmw, less than 40 ppmw, less than 30 ppmw, less than 20 ppmw, less than 10 ppmw, less than 5 ppmw, less than 2 ppmw, or less than 1 ppmw of fluoropolymers.

[0039] Additional optional additives are contemplated for the formulation. In some embodiments, the composition may comprise one or more other additives. Non-limiting examples of suitable other additives include antioxidants, antistatic agents, stabilizers, nucleating agents, colorants, pigments, ultraviolet (UV) absorbers or stabilizers, slip agents, anti-caking agents, flame retardants, compatibilizers, plasticizers, fillers, processing aids, anti-fogging additives, crosslinking agents (such as peroxides), and combinations thereof. All individual values and subranges from 0 wt% to 3 wt% are included and disclosed herein; for example, the total amount of additives in the polymer copolymer can be from a lower limit of 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, or 4.5 wt% to an upper limit of from 1 wt%, 2 wt%, 3 wt%, 4 wt%, or 5 wt%.

[0040] It is considered that various processing procedures are applicable to the production of processing aid formulations. For example, it is expected to add the processing aid components in various sequences. In one or more embodiments, the processing aid can be prepared by first forming a masterbatch of one or more of PDMS, polyalkylene glycol, and polymeric phosphite in a polyethylene resin. In an embodiment, forming the masterbatch in the polyethylene resin can include compounding the polyethylene resin with one or more of PDMS, polyalkylene glycol, and polymeric phosphite. The masterbatch can be combined with the polymer resin to reduce melt fracture in the base resin in the extruder, thereby producing the finished product. The masterbatch can be melt blended or dry blended with the base resin before or during extrusion to produce a product with reduced melt fracture. The base resin can include ethylene-based polymers such as LLDPE.

[0041] In one or more embodiments, the formulation can clear melt fracture in less than or equal to 120 minutes (min). In an embodiment, the formulation can clear melt fracture in less than 200 minutes, less than 175 minutes, less than 150 minutes, less than 125 minutes, less than or equal to 120 minutes, less than or equal to 110 minutes, less than or equal to 100 minutes, less than or equal to 90 minutes, less than or equal to 80 minutes, less than or equal to 70 minutes, less than or equal to 60 minutes, less than or equal to 50 minutes, or less than or equal to 40 minutes.

[0042] Product

[0043] In one or more embodiments, the product can be produced from the base resin and the PPA formulation described herein. The product can include a film, such as a monolayer film or a multilayer film. The product containing the film can include non-rigid packaging, such as flexible packaging, pouches, stand-up pouches, etc. The product can also include rigid packaging, such as wires and cables, pipes, etc. The product can also include a tube or pipe or wire.

[0044] Test Method

[0045] Melt index (190 °C, 2.16 kg, "I2") test method: Use ASTM D1238-13 "Standard Test Method for Melt Flow Rates of Thermoplastics by Extrusion Platometer", under the conditions of 190 °C / 2.16 kilograms (kg). The results are reported in grams per 10 minutes of elution (g / 10min).

[0046] Density measurements were performed according to ASTM D4703. According to ASTM D792, Method B, measurements were made within one hour of pressing the sample.

[0047] The average molecular weight (MW) can be determined according to ASTM D4274, the entire protocol of ASTM D4274 is incorporated herein by reference.

[0048] The kinematic viscosity of PDMS was measured using an MCR 301 rheometer commercially available from Anton-Paar. The rheometer was equipped with a 25 millimeter (mm) stainless steel cone and plate fixture at an operating temperature of 25 °C. Steady shear measurements were performed at shear rates in the range of 0.1 s-1 to 500 s-1. Before each measurement, the material was allowed to equilibrate for at least 5 minutes. The kinematic viscosity is the average viscosity at a shear rate of -1 from 0.1 s -1 to 10 s.

[0049] Example

[0050] The following examples are provided by way of illustration and are presented in a manner that should be recognized by those skilled in the art and are not meant to limit the disclosure as a whole or the appended claims.

[0051] The following commercial compositions were used in the following examples.

[0052] DOWLEX TM DOWLEX 2047G is a commercial LLDPE resin available from Dow Inc, Midland, MI, having a density of 0.915 g / cc to 0.919 g / cc and a melt index (I2) of 2.0 g / 10 min to 2.6 g / 10 min.

[0053] PDMS-1 is a commercial polydimethylsiloxane silanol functional polymer also available from Dow Inc, having a kinematic viscosity of 50,000 cSt.

[0054] PDMS-2 is a commercial polydimethylsiloxane silicone fluid available from Dow Inc, having a kinematic viscosity of 60,000 cSt.

[0055] The comparative masterbatch contains 8 wt% of Dynamar TM 5920 fluoropolymer, and Ziegler-Natta catalyzed LLDPE having a density of 0.917 g / cc and a melt index (I2) of 2.3 g / 10 min.

[0056] LGP - 12 polyphosphite, commercially available from Dover Chemical.

[0057] CARBOWAX commercially available from Dow Chemical TM 8000 PEG has a molecular weight of 7000 g / mol to 9000 g / mol.

[0058] CARBOWAX commercially available from Dow Chemical TM 3350 PEG has a molecular weight of 3015 g / mol to 3685 g / mol.

[0059] Example 1

[0060] Produce experimental LLDPE resin 1 with a melt index of 0.5 g / 10 min and a density of 0.905 grams per milliliter (g / mL).

[0061] Purify the raw materials and Isopar TM E, this Isopar TM E is a high - purity isoparaffinic solvent with a narrow boiling range, commercially available from ExxonMobil. Hydrogen is supplied in a high - purity grade and is not further purified.

[0062] Two reactor systems are used in a series configuration. Each continuous solution polymerization reactor includes a liquid - filled non - adiabatic isothermal circulation loop reactor that simulates a continuous stirred - tank reactor (CSTR) with heat removal. Independent control of all feeds is possible.

[0063] Feed three feed streams: solvent / ethylene feed stream, comonomer / ethylene feed stream, and hydrogen / ethylene feed stream into the first and second reactors. The feed stream conditions and compositions are shown in Table 1. Pressurize the feed streams to greater than the reaction pressure via a mechanical compressor or pump. Manually batch - dilute each catalyst component with the purified solvent and pressurize it to greater than the reaction pressure. All reaction feed streams are measured with mass flow meters and independently controlled with a computer - automated valve control system.

[0064] Table 1: Reaction Conditions

[0065] Reactor Configuration Type Double Series Comonomer Type Type 1-Octene Mass Flow Ratio of Solvent to Ethylene in the Feed of the First Reactor g / g 5.3 Mass Flow Ratio of Comonomer to Ethylene in the Feed of the First Reactor g / g 0.65 Mass Flow Ratio of Hydrogen to Ethylene in the Feed of the First Reactor g / g 2.0E-04 Temperature of the First Reactor ℃ 141 Pressure of the First Reactor barg 50 Ethylene Conversion in the First Reactor ％ 79.2 Catalyst Type in the First Reactor Type Catalyst Component 1 Type of Cocatalyst 1 in the First Reactor Type Cocatalyst 1 Type of Cocatalyst 2 in the First Reactor Type Cocatalyst 2 Molar Ratio of Cocatalyst 1 to Catalyst in the First Reactor (Ratio of B to Zr) Ratio 2.0 Molar Ratio of Cocatalyst 2 to Catalyst in the First Reactor (Ratio of Al to Zr) Ratio 74.1 Residence Time in the First Reactor min 17.2 Percentage of Ethylene Feed Entering the First Reactor wt% 59.2 Mass Flow Ratio of Solvent to Ethylene in the Feed of the Second Reactor g / g 2.5 Mass Flow Ratio of Comonomer to Ethylene in the Feed of the Second Reactor g / g 0.186 Mass Flow Ratio of Hydrogen to Ethylene in the Feed of the Second Reactor g / g 3.0E-04 Temperature of the Second Reactor ℃ 190 Pressure of the Second Reactor barg 50 Ethylene Conversion in the Second Reactor ％ 85.9 Catalyst Type in the Second Reactor Type Catalyst Component 1 Type of Cocatalyst 1 in the Second Reactor Type Cocatalyst 1 Type of Cocatalyst 2 in the Second Reactor Type Cocatalyst 2 Molar Ratio of Cocatalyst 1 to Catalyst in the Second Reactor (Ratio of B to Zr) mol / mol 1.4 Molar Ratio of Cocatalyst 2 to Catalyst in the Second Reactor (Ratio of Al to Zr) mol / mol 7.0 Residence Time in the Second Reactor min 7.3

[0066] Thermally control the total fresh feed stream entering each reactor to maintain a single solution phase by passing the feed stream through a heat exchanger. Inject the feed stream of each reactor into each reactor at two locations, with approximately equal reactor volumes between each injection location. Control the feed stream such that each injector receives half of the total fresh feed mass flow rate.

[0067] The catalyst components (shown in Table 2) are injected into each polymerization reactor through a specially designed injection stinger. The computer controls the feed of the main catalyst component to maintain each reactor monomer conversion at a specified target. The cocatalyst component is fed to the main catalyst component based on the calculated specified molar ratio.

[0068] Table 2: Catalyst Components

[0069]

[0070] After injection, the feed stream is immediately mixed with the recycled polymerization reactor contents using a static mixing element. The contents of each reactor are continuously circulated through a heat exchanger that is responsible for removing most of the reaction heat, and the temperature on the coolant side of which is responsible for maintaining the isothermal reaction environment at a specified temperature. The circulation around each reactor loop is provided by a pump.

[0071] The effluent from the first polymerization reactor (containing solvent, monomer, comonomer, hydrogen, catalyst components, and polymer) leaves the first reactor loop and is added to the second reactor loop.

[0072] The final reactor effluent (effluent from the second reactor in a double-tandem configuration) enters a zone where a suitable reagent (such as water) is added and reacts with the suitable reagent to deactivate the final reactor effluent. At the same reactor outlet location, other additives are added for polymer stabilization (typical antioxidants suitable for stabilization during extrusion and blown film fabrication, such as octadecyl 3,5 - di - tert - butyl - 4 - hydroxyhydrocinnamate, tris(2,4 - di - tert - butylphenyl) phosphite, and tetrakis(methylene(3,5 - di - tert - butyl - 4 - hydroxyhydrocinnamate)) methane).

[0073] After catalyst deactivation and addition of additives, the reactor effluent enters a devolatilization system where the polymer is removed from the non - polymer stream. The separated polymer melt is pelletized and collected. The non - polymer stream passes through various devices that separate most of the ethylene removed from the system. Most of the solvent and unreacted comonomer are recycled back to the reactor system after passing through a purification system. A small amount of solvent and comonomer are purged from the process.

[0074] Example 2

[0075] In this example, a product containing DOWLEX is produced TMProcessing aid masterbatch for 2047G polyethylene resin. In some formulations, the polyethylene resin is compounded with silicone. In some formulations, the silicone is PDMS-1 or PDMS-2. Additionally, as described above, a comparative masterbatch containing a fluoropolymer was also prepared.

[0076] The experimental LLDPE resin 1 prepared according to Example 1 was added as the base resin to a twin-screw extruder (TSE) without any processing aids until the flow stabilized, which resulted in melt fracture in the extrudate. The TSE was a ZSK 18MEGAlab, an 18 mm co-rotating TSE, commercially available from Coperion. The ratio of the screw thread length to the outer diameter (L / D) of the TSE was 40, and the ratio of the outer diameter to the inner diameter (D o / D i ) was 1.55. The processing conditions used are provided in Table 3. An uncoated split slit die with a slit width of 10 mm, a flow length of 10 mm, and a die gap of 2 mm was used to screen the formulations at an apparent shear rate of 151 s- 1 .

[0077] Table 3: Processing Conditions Used in TSE

[0078] Temperature of Zone 1 (°C) 170 Temperature of Zone 2 (°C) 190 Temperature of Zone 3 (°C) 190 Temperatures of Zones 4 to 7 (°C) 190 Screw Speed (RPM) 300

[0079] Subsequently, the masterbatch and other components were dry-blended and fed into the same hopper of the TSE to produce polymer processing aid (PPA) formulations as shown in Table 4.

[0080] Table 4: PPA Formulations by Formulation Number

[0081]

[0082]

[0083] After melt fracture was reached, the PPA formulations were introduced, and the time required for visual clearance of the melt fracture was recorded, as shown in Table 5. When the formulations were introduced into the extruder after the base resin for extrusion had stabilized, the timer was started. If the melt fracture was not cleared after 120 minutes, the timer was stopped.

[0084] After each formulation, the extruder was purged with the base resin until melt fracture was fully re-established, which was also visually confirmed by the stabilization of the processing conditions (extruder torque, pressure). The processing data for the PPA formulations are listed in Table 6.

[0085] Table 5: Time to Eliminate Melt Fracture by Formulation Number

[0086] Formulation Number Time to Eliminate Melt Fracture (minutes) CE1 100 CE2 Not Eliminated at 120 Minutes CE3 Not Eliminated at 120 Minutes CE4 Not Eliminated at 120 Minutes CE5 Not Eliminated at 120 Minutes CE6 Not Eliminated at 120 Minutes CE7 Not Eliminated at 120 Minutes CE8 Not Eliminated at 120 Minutes CE9 Not Eliminated at 120 Minutes CE10 Not Eliminated at 120 Minutes IE1 70 IE2 40 IE3 110 IE4 40 IE5 80

[0087] Table 6: Process Data of Various Formulations

[0088]

[0089] As shown in Tables 4 and 5, CE2 with only polymeric phosphite as a processing aid, CE3 with only PEG as a processing aid, and CE4 with only PDMS as a processing aid all failed to clear the melt fracture within 120 minutes.

[0090] In addition, as shown by CE4 to CE8, formulations containing only two processing aid components selected from the list consisting of PEG, polymeric phosphite, and PDMS also did not clear the melt fracture within 120 minutes.

[0091] Furthermore, when using less than 500 ppmw of PEG, formulations containing polyalkylene glycol, polymeric phosphite, and PDMS may be less effective, as shown by CE9 which uses only 360 ppmw of PEG and only partially clears the melt fracture after 120 minutes.

[0092] In addition, formulation CE10 using unsubstituted PDMS failed to clear the melt fracture within 120 minutes.

[0093] IE1 to IE5 containing PEG, polymeric phosphite, and substituted PDMS as processing aids cleared the melt fracture in less than 120 minutes. Furthermore, they cleared the melt fracture even faster than CE1, which is a formulation containing a fluoropolymer. This is even more significant when considering that the formulations of the present invention do not include the same environmental persistence issues as fluoropolymer processing aids.

[0094] The subject matter of the present disclosure has been described in detail and with reference to specific embodiments. It should be understood that any detailed description of a component or feature of an embodiment does not necessarily imply that the component or feature is necessary for a particular embodiment or any other embodiment. Further, it will be apparent to those skilled in the art that various modifications and changes can be made to the described embodiments without departing from the essence and scope of the claimed subject matter.

[0095] It should be noted that one or more of the appended claims utilize the term "wherein" as a transitional phrase. For the purpose of defining the present technology, it should be noted that this term is introduced in the claims as an open transitional phrase that is used to introduce a recitation of a series of characteristics of a structure and should be interpreted in a manner similar to the more commonly used open preamble term "comprising".

[0096] It should be understood that where a first component is described as "comprising" a second component, it is contemplated that in embodiments, the first component "consists of" or "consists essentially of" the second component. It should also be understood that where a first component is described as "comprising" a second component, it is contemplated that in embodiments, the first component may comprise at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95% or even at least 99% of the second component (where % may be % by weight or % by mole).

[0097] It should also be noted that references herein to "at least one" component, element, etc. should not be used to create an inference that the alternative use of the article "a / an" should be limited to a single component, element, etc.

Claims

1. A formulation, the formulation comprising: at least 95 wt% of an ethylene-based polymer; a polymeric phosphite; a substituted polydimethylsiloxane (PDMS); and at least 500 ppmw of a polyalkylene glycol.

2. The formulation according to claim 1, wherein the polyalkylene glycol is polyethylene glycol (PEG) having an average molecular weight (MW) of 1,000 to 40,000.

3. The formulation according to any one of the preceding claims, wherein the formulation is substantially free of fluoropolymers.

4. The formulation according to any one of the preceding claims, wherein the polymeric phosphite is a liquid polymeric phosphite.

5. The formulation according to any one of the preceding claims, wherein the substituted PDMS comprises a hydroxyl group, a carboxyl group, an amino functional group, or a combination thereof.

6. The formulation according to any one of the preceding claims, wherein the substituted PDMS includes silanol-terminated PDMS.

7. The formulation according to any one of the preceding claims, wherein the substituted PDMS has a kinematic viscosity of at least 1,000 cSt to 100,000 cSt.

8. The formulation according to any one of the preceding claims, wherein the ethylene-based polymer includes LLDPE.

9. An article, the article being produced from the formulation according to any one of the preceding claims.

10. A method of manufacturing an article, the method comprising: Extruding a polymer melt comprising the formulation according to any one of the preceding claims to produce the article.

11. The method according to claim 10, wherein the article includes a rigid article and a film.

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