Patent Application
20220162400
Crosslinked polyethylene (XLPE) is widely used for high voltage insulation in power transmission systems. One way to produce XLPE is by way of a silane/moisture cure process. In a silane/moisture cure process, silane is grafted onto polyethylene in a reactive extrusion procedure in the presence of peroxide initiator. The resulting silane-grafted resin produces silane crosslinked polyethylene.
Drawbacks to the silane/moisture cure process include the environmental, health, and safety hazards associated with the handling and use of silane and peroxide. In addition, peroxide crosslinking of polyethylene generates by-products due to the decomposition of the peroxide. For example, dicumyl peroxide (DCP), a common crosslinking agent, typically decomposes and generates methane, acetophenone, and cumyl alcohol during polyethylene crosslinking. These crosslink by-products can deleteriously impact the electrical properties of XPLE power cables.
The art recognizes the on-going need to reduce the amount of peroxide and/or silane during the silane/moisture cure procedure for the crosslinking of olefin-based polymers and the crosslinking of polyethylene in particular.
The present disclosure provides a pellet. In an embodiment, the pellet includes: a body having a first end and an opposing second end. The body is composed of a polymeric material. The body has a length, a diameter (body diameter) and a channel. The channel has a diameter (channel diameter), the channel extends through the body from the first end to the second end. An additive in is the channel.
Also provided is a process. The process includes forming a pellet in a melt state, the pellet having a body, the body having a first end and an opposing second end. The body is composed of a polymeric material. The pellet has a channel extending through the body from the first end to the second end. The process includes injecting an additive into the channel while the additive is in a fluid state. The process includes solidifying the pellet and forming a loaded pellet where the loaded pellet has the additive in the channel.
For purposes of United States patent practice, the contents of any referenced patent, patent application or publication are incorporated by reference in their entirety (or its equivalent U.S. version is so incorporated by reference), especially with respect to the disclosure of definitions (to the extent not inconsistent with any definitions specifically provided in this disclosure) and general knowledge in the art.
The numerical ranges disclosed herein include all values from, and including, the lower value and the upper value. For ranges containing explicit values (e.g., 1, or 2, or 3 to 5, or 6, or 7) any subrange between any two explicit values is included (e.g., 1 to 2; 2 to 6; 5 to 7; 3 to 7; 5 to 6; etc.).
The terms “comprising,” “including,” “having,” and their derivatives, are not intended to exclude the presence of any additional component, step or procedure, whether or not the same is specifically disclosed. In order to avoid any doubt, all compositions claimed through use of the term “comprising” may include any additional additive, adjuvant, or compound, (whether polymerized or otherwise), unless stated to the contrary. In contrast, the term, “consisting essentially of” excludes from the scope of any succeeding recitation any other component, step, or procedure, excepting those that are not essential to operability. The term “consisting of” excludes any component, step, or procedure not specifically delineated or listed. The term “or,” unless stated otherwise, refers to the listed members individually as well as in any combination. Use of the singular includes use of the plural and vice versa.
Unless stated to the contrary, implicit from the context, or customary in the art, all parts and percentages are based on weight and all test methods are current as of the filing date of this disclosure.
“Blend,” “polymer blend” and like terms refer to a combination of two or more polymers. Such a blend may or may not be miscible. Such a combination may or may not be phase separated. Such a combination may or may not contain one or more domain configurations, as determined from transmission electron spectroscopy, light scattering, x-ray scattering, and any other method known in the art.
“Ethylene-based polymer” is a polymer that contains more than 50 weight percent polymerized ethylene monomer (based on the total amount of polymerizable monomers) and, optionally, may contain at least one comonomer. Ethylene-based polymer includes ethylene homopolymer, and ethylene copolymer (meaning units derived from ethylene and one or more comonomers). The terms “ethylene-based polymer” and “polyethylene” may be used interchangeably. Nonlimiting examples of ethylene-based polymer (polyethylene) include low density polyethylene (LDPE) and linear polyethylene. Nonlimiting examples of linear polyethylene include linear low density polyethylene (LLDPE), ultra-low density polyethylene (ULDPE), very low density polyethylene (VLDPE), multi-component ethylene-based copolymer (EPE), ethylene/α-olefin multi-block copolymers (also known as olefin block copolymer (OBC)), single-site catalyzed linear low density polyethylene (m-LLDPE), substantially linear, or linear, plastomers/elastomers, medium density polyethylene (MDPE), and high density polyethylene (HDPE). Generally, polyethylene may be produced in gas-phase, fluidized bed reactors, liquid phase slurry process reactors, or liquid phase solution process reactors, using a heterogeneous catalyst system, such as Ziegler-Natta catalyst, a homogeneous catalyst system, comprising Group 4 transition metals and ligand structures such as metallocene, non-metallocene metal-centered, heteroaryl, heterovalent aryloxyether, phosphinimine, and others. Combinations of heterogeneous and/or homogeneous catalysts also may be used in either single reactor or dual reactor configurations. In an embodiment, the ethylene-based polymer does not contain an aromatic comonomer polymerized therein.
“Ethylene plastomers/elastomers” are substantially linear, or linear, ethylene/α-olefin copolymers containing homogeneous short-chain branching distribution comprising units derived from ethylene and units derived from at least one C3-C10 α-olefin comonomer, or at least one C4-C8 α-olefin comonomer, or at least one C6-C8 α-olefin comonomer. Ethylene plastomers/elastomers have a density from 0.870 g/cc, or 0.880 g/cc, or 0.890 g/cc to 0.900 g/cc, or 0.902 g/cc, or 0.904 g/cc, or 0.909 g/cc, or 0.910 g/cc, or 0.917 g/cc. Nonlimiting examples of ethylene plastomers/elastomers include AFFINITY™ plastomers and elastomers (available from The Dow Chemical Company), EXACT™ Plastomers (available from ExxonMobil Chemical), Tafmer™ (available from Mitsui), Nexlene™ (available from SK Chemicals Co.), and Lucene™ (available LG Chem Ltd.).
“High density polyethylene” (or “HDPE”) is an ethylene homopolymer or an ethylene/α-olefin copolymer with at least one C4-C10 α-olefin comonomer, or C4-C8 α-olefin comonomer and a density from greater than 0.94 g/cc, or 0.945 g/cc, or 0.95 g/cc, or 0.955 g/cc to 0.96 g/cc, or 0.97 g/cc, or 0.98 g/cc. The HDPE can be a monomodal copolymer or a multimodal copolymer. A “monomodal ethylene copolymer” is an ethylene/C4-C10 α-olefin copolymer that has one distinct peak in a gel permeation chromatography (GPC) showing the molecular weight distribution. A “multimodal ethylene copolymer” is an ethylene/C4-C10α-olefin copolymer that has at least two distinct peaks in a GPC showing the molecular weight distribution. Multimodal includes copolymer having two peaks (bimodal) as well as copolymer having more than two peaks. Nonlimiting examples of HDPE include DOW™ High Density Polyethylene (HDPE) Resins, ELITE™ Enhanced Polyethylene Resins, and CONTINUUM™ Bimodal Polyethylene Resins, each available from The Dow Chemical Company; LUPOLEN™, available from LyondeliBasell; and HDPE products from Borealis, Ineos, and ExxonMobil.
An “interpolymer” (or “copolymer”), is a polymer prepared by the polymerization of at least two different monomers. This generic term includes copolymers, usually employed to refer to polymers prepared from two different monomers, and polymers prepared from more than two different monomers, e.g., terpolymers, tetrapolymers, etc.
“Low density polyethylene” (or “LDPE”) consists of ethylene homopolymer, or ethylene/α-olefin copolymer comprising at least one C3-C10 α-olefin, preferably C3-C4 that has a density from 0.915 g/cc to 0.940 g/cc and contains long chain branching with broad MWD. LDPE is typically produced by way of high pressure free radical polymerization (tubular reactor or autoclave with free radical initiator). Nonlimiting examples of LDPE include MarFlex™ (Chevron Phillips), LUPOLEN™ (LyondellBasell), as well as LDPE products from Borealis, Ineos, ExxonMobil, and others.
“Linear low density polyethylene” (or “LLDPE”) is a linear ethylene/α-olefin copolymer containing heterogeneous short-chain branching distribution comprising units derived from ethylene and units derived from at least one C3-C10 α-olefin comonomer or at least one C4-C8 α-olefin comonomer, or at least one C6-C8 α-olefin comonomer. LLDPE is characterized by little, if any, long chain branching, in contrast to conventional LDPE. LLDPE has a density from 0.910 g/cc, or 0.915 g/cc, or 0.920 g/cc, or 0.925 g/cc to 0.930 g/cc, or 0.935 g/cc, or 0.940 g/cc. Nonlimiting examples of LLDPE include TUFLIN™ linear low density polyethylene resins and DOWLEX™ polyethylene resins, each available from the Dow Chemical Company; and MARLEX™ polyethylene (available from Chevron Phillips).
“Multi-component ethylene-based copolymer” (or “EPE”) comprises units derived from ethylene and units derived from at least one C3-C10 α-olefin comonomer, or at least one C4-C8 α-olefin comonomer, or at least one C6-C8 α-olefin comonomer, such as described in patent references U.S. Pat. Nos. 6,111,023; 5,677,383; and 6,984,695. EPE resins have a density from 0.905 g/cc, or 0.908 g/cc, or 0.912 g/cc, or 0.920 g/cc to 0.926 g/cc, or 0.929 g/cc, or 0.940 g/cc, or 0.962 g/cc. Nonlimiting examples of EPE resins include ELITE™ enhanced polyethylene and ELITE AT™ advanced technology resins, each available from The Dow Chemical Company; SURPASS™ Polyethylene (PE) Resins, available from Nova Chemicals; and SMART™, available from SK Chemicals Co.
An “olefin-based polymer” or “polyolefin” is a polymer that contains more than 50 weight percent polymerized olefin monomer (based on total amount of polymerizable monomers), and optionally, may contain at least one comonomer. Nonlimiting examples of an olefin-based polymer include ethylene-based polymer and propylene-based polymer. An “olefin” and like terms refers to hydrocarbons consisting of hydrogen and carbon whose molecules contain a pair of carbon atoms linked together by a double bond.
A “polymer” is a compound prepared by polymerizing monomers, whether of the same or a different type, that in polymerized form provide the multiple and/or repeating “units” or “mer units” that make up a polymer. The generic term polymer thus embraces the term “homopolymer,” usually employed to refer to polymers prepared from only one type of monomer, but not at the exclusion of residual amounts of other components used in preparing the homopolymer, such as chain transfer agents. The term “copolymer,” usually employed to refer to polymers prepared from at least two types of monomers. It also embraces all forms of copolymer, e.g., random, block, etc. The terms “ethylene/α-olefin polymer” and “propylene/α-olefin polymer” are indicative of copolymer as described above prepared from polymerizing ethylene or propylene respectively and one or more additional, polymerizable α-olefin monomer. It is noted that although a polymer is often referred to as being “made of” one or more specified monomers, “based on” a specified monomer or monomer type, “containing” a specified monomer content, or the like, in this context the term “monomer” is understood to be referring to the polymerized remnant of the specified monomer and not to the unpolymerized species. In general, polymers herein are referred to has being based on “units” that are the polymerized form of a corresponding monomer.
“Single-site catalyzed linear low density polyethylenes” (or “m-LLDPE”) are linear ethylene/α-olefin copolymers containing homogeneous short-chain branching distribution comprising units derived from ethylene and units derived from at least one C3-C10 α-olefin comonomer, or at least one C4-C8 α-olefin comonomer, or at least one C6-C8 α-olefin comonomer. m-LLDPE has density from 0.913 g/cc, or 0.918 g/cc, or 0.920 g/cc to 0.925 g/cc, or 0.940 g/cc. Nonlimiting examples of m-LLDPE include EXCEED™ metallocene PE (available from ExxonMobil Chemical), LUFLEXEN™ m-LLDPE (available from LyondellBasell), and ELTEX™ PF m-LLDPE (available from Ineos Olefins & Polymers).
“Ultra low density polyethylene” (or “ULDPE”) and “very low density polyethylene” (or “VLDPE”) each is a linear ethylene/α-olefin copolymer containing heterogeneous short-chain branching distribution comprising units derived from ethylene and units derived from at least one C3-C10 α-olefin comonomer, or at least one C4-C8 α-olefin comonomer, or at least one C6-C8 α-olefin comonomer. ULDPE and VLDPE each has a density from 0.885 g/cc, or 0.90 g/cc to 0.915 g/cc. Nonlimiting examples of ULDPE and VLDPE include ATTANE™ ULDPE resins and FLEXOMER™ VLDPE resins, each available from The Dow Chemical Company.
“Melt blending” is a process in which at least two components are combined or otherwise mixed together, and at least one of the components is in a melted state. The melt blending may be accomplished by one or more of various know processes, e.g., batch mixing, extrusion blending, extrusion molding, and the like. “Melt blended” compositions are compositions which were formed through the process of melt blending.
“Thermoplastic polymer” and like terms refers to a linear or branched polymer that can be repeatedly softened and made flowable when heated and returned to a hard state when cooled to room temperature. A thermoplastic polymer typically has an elastic modulus greater than 68.95 MPa (10,000 psi) as measured in accordance with ASTM D638-72. In addition, a thermoplastic polymer can be molded or extruded into an article of any predetermined shape when heated to the softened state.
“Thermoset polymer”, “thermosetting polymers” and like terms indicate that once cured, the polymer cannot be softened nor further shaped by heat. Thermosetting polymers, once cured, are space network polymers and are highly crosslinked to form rigid three-dimensional molecular structures.
The present disclosure provides a pellet. In an embodiment, the pellet includes a body that is composed of a polymeric material. The body has a first end and a second end located on an opposite side of the body. The body includes a length and a diameter. The body has a channel having a channel diameter. The channel extends through the body from the first end to the second end. An additive is located in the channel.
Pellet
Referring to the drawings and initially to
The body 20 has a cylindrical shape. The body 20 includes the first end 15 and the second end 25, the ends having a circular shape. The first end 15 and the second end 25 are located on opposite side of the body 20. An axis of symmetry A is located at the center of circles formed by the ends 15 and 25. Pellet 10 includes a channel 30 that is parallel to the axis of symmetry A. The channel 30 has a cylindrical shape, or a generally cylindrical shape, and is located in the center of the body 20. The channel 30 spans the entire length of the body 20. Channel 30 extends from the first end 15 to the second end 25.
Body 20 has a circular, or a generally circular, cross-sectional shape. Body 20 also has a cylindrical, or a generally cylindrical shape. It is understood that the circular, cross-sectional shape of the body 20 can be altered (i.e., squeezed, pressed or packed), due to forces imparted upon the pellet 10 during industrial scale production and/or handling of the pellet while the pellet is still in a melted state. Consequently, the cross-sectional shape of the body 20 may be more elliptical in shape than circular in shape, thus the definition of “generally circular in cross-sectional shape.”
The body 20 and the channel 30 each has a respective diameter—body diameter 40 and channel diameter 45. The term, “diameter,” as used herein, is the greatest length between two points on body/channel surface that extends through the center, through axis of symmetry A, of the body/channel. In other words, when the pellet 10 has an elliptical shape (as opposed to a circular shape), the diameter is the major axis of the ellipse. In an embodiment, the shape of the body 20 resembles a hockey puck.
Additive
An additive 100 is present in the channel 30 as shown in
In an embodiment, the additive 100 includes a material having at least one C—Si—O group. The term, “C—Si—O group,” as used herein, is a moiety within an organic molecule having a carbon atom covalently bonded to a silicon atom, the silicon atom covalently bonded to an oxygen atom.
In an embodiment, the material having at least one C—Si—O group is a siloxane.
In an embodiment the siloxane is polydimethylsiloxane (PDMS).
In an embodiment, the material having at least one C—Si—O group is a silane. The silane is a hydrolysable silane having the following Structure (A):
wherein R′ is a hydrogen atom or methyl group; x and y are 0 or 1 with the proviso that when x is 1, y is 1; n is an integer from 1 to 12 inclusive, or n is an integer from 1 to 4, and each R″ independently is a hydrolysable organic group such as an alkoxy group having from 1 to 12 carbon atoms (e.g., methoxy, ethoxy, butoxy), aryloxy group (e.g., phenoxy), araloxy group (e.g., benzyloxy), aliphatic acyloxy group having from 1 to 12 carbon atoms (e.g., formyloxy, acetyloxy, propanoyloxy), amino or substituted amino groups (alkylamino, arylamino), or a lower alkyl group having 1 to 6 carbon atoms inclusive, with the proviso that at least one of the three “R” groups forms an Si—O bond with the silicon atom.
Nonlimiting examples of suitable hydrolysable silane include silanes that have an ethylenically unsaturated hydrocarbyl group, such as vinyl, allyl, isopropenyl, butenyl, cyclohexenyl or gamma-(meth)acryloxy allyl group, and a hydrolysable group, such as, for example, a hydrocarbyloxy, hydrocarbonyloxy, or hydrocarbylamino group. Examples of hydrolysable groups include methoxy, ethoxy, formyloxy, acetoxy, propionyloxy, and alkyl or arylamino groups.
In an embodiment, the hydrolysable silane is an unsaturated alkoxy silane such as vinyl trimethoxy silane (VTMS), vinyl triethoxy silane, vinyl triacetoxy silane, gamma-(meth)acryloxy, propyl trimethoxy silane, and mixtures of these silanes.
In an embodiment, the additive 100 includes a peroxide, a silane, a catalyst, a curing coagent, an antioxidant, an azo compound, a flame retardant, a metal deactivator, a UV stabilizer, a voltage stabilizer, a water tree retardant, or combinations thereof.
Nonlimiting examples of suitable peroxide include cumene hydroperoxide, dicumyl peroxide (DCP), isopropylcumyl t-butyl peroxide, t-butyl cumylperoxide, isopropyl cumylperoxide, di(isopropylcumyl) peroxide, di-t-amyl peroxide (DTAP), di-t-butyl peroxide, benzoyl peroxide, lauryl peroxide, methyl ethyl ketone peroxide, bis(1,1-dimethylethyl) peroxide, bis(1,1-dimethylpropyl) peroxide, t-butyl peracetate, t-butyl peroctoate, t-butyl peroxybenzoate, 2,5-dimethyl-2,5-bis(1,1-dimethylethylperoxy) hexane, 2,5-dimethyl-2,5-bis(1,1-dimethylethylperoxy) hexyne, 2,5-bis(t-butyl peroxy)-2,5-dimethylhexane, 2,5-bis(t-butyl peroxy)-2,5-dimethylhexyne, 3,1,1-bis(t-butyl peroxy)-3,3,5-trimethylcyclohexane, 1,1-bis(1,1-dimethylethylperoxy)-3,3,5-trimethylcyclohexane, bis(α-t-butyl-peroxyisopropyl) benzene (BIPB), butyl 4,4-di(tert-butylperoxy) valerate, and 4,4-bis(1,1-dimethylethylperoxy) valeric acid.
Nonlimiting examples of suitable catalyst include coordination complexes comprising tin and an organic ligand, such as dialkyltin dicarboxylates. In an embodiment, the dialkyltin dicarboxylate is a di((C1-C10)alkyl)tin dicarboxylate, a dialkyltin di(C8-C18)carboxylate, a di((C1-C10)alkyl)tin di(C8-C18)carboxylate, a di((C3-C5)alkyl)tin di(C10-C14)carboxylate, a di((C4)alkyl)tin di(C12)carboxylate, or a combination thereof. In a further embodiment, the dialkyltin dicarboxylate is dibutyltin dilaurate.
Nonlimiting examples of suitable curing coagent include 2-allylphenyl allyl ether; 4-isopropenyl-2,6-dimethylphenyl allyl ether; 2,6-dimethyl-4-allylphenyl allyl ether; 2-methoxy-4-allylphenyl allyl ether; 2,2′-diallyl bisphenol A; O,O′-diallyl bisphenol A (or tetramethyl diallylbisphenol A); 2,4-diphenyl-4-methyl-1-pentene (or 1,3-diisopropenylbenzene)′, triallyl isocyanurate (“TAIC”); triallyl cyanurate (“TAC”), triallyl trimellitate (“TATM”); N,N,N′,N′,N″,N″-hexaallyl-1,3,5-triazine-2,4,6-triamine (“HATATA”), (also known as N2,N2,N4,N4,N6,N6-hexaallyl-1,3,5-triazine-2,4,6-triamine); triallyl orthoformate; pentaerythritol triallyl ether; triallyl citrate (or triallyl aconitate); trimethylolpropane triacrylate (“TMPTA”); trimethylolpropane trimethylacrylate (“TMPTMA”); ethoxylated bisphenol A dimethacrylate; 1,6-hexanediol diacrylate; pentaerythritol tetraacrylate; dipentaerythritol pentaacrylate; tris(2-hydroxyethyl) isocyanurate triacrylate; propoxylated glyceryl triacrylate; trimethylallyl isocyanurate (TMAIC); N,N-m-phenylene dimaleimide; and zinc dimethacrylate.
Nonlimiting examples of suitable antioxidant include bis(4-(1-methyl-1-phenylethyl)phenyl)amine, 2,2′-methylene-bis(4-methyl-6-t-butylphenol), 2,2′-thiobis(2-t-butyl-5-methylphenol, 4,4′-thiobis(2-t-butyl-5-methylphenol) (or 4,4′-thiobis(6-tert-butyl-m-cresol), 2,2′-thiobis(6-t-butyl-4-methylphenol, tris[(4-tert-butyl-3-hydroxy-2,6-dimethylphenyl)methyl]-1,3,5-triazine-2,4,6-trione, pentaerythritol tetrakis(3-(3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl)propionate, 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid, 2,2′-thiodiethanediyl ester, distearyl thiodipropionate (“DSTDP”), dilauryl thiodipropionate, stearyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 2,4-bis(dodecylthiomethyl)-6-methylphenol, 4,6-bis(octylthiomethyl)-o-cresol, 2′,3-bis[[3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyl]] propionohydrazide, 4,4′-bis-(α,α-dimethylbenzyl) diphenylamine, and sulfanediyldiethane-2,1-diyl-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate].
A nonlimiting example of a suitable azo compound is 2,2-azobisisobutyronitrile.
In an embodiment, the additive is an additive blend. The additive blend includes two or more additives as described herein.
In an embodiment, the additive blend includes a carrier. Nonlimiting examples of suitable carrier include olefin-based polymer, wax, and a combination thereof. The two or more additives of the additive blend are dispersed homogenously throughout the carrier.
In an embodiment, the carrier includes a solidifier.
In an embodiment, the solidifier is a nucleating agent. Nonlimiting examples of suitable nucleating agent include talc, a carboxylate salt (e.g., sodium benzoate), a sorbitol acetal, a clarifier, a phosphate ester salt, an organic pigment and an inorganic pigment. Not wishing to bound by theory, the mixture of the carrier and the solidifier can facilitate solidification of the additives within the carrier located inside the pellet.
In an embodiment, the carrier is wax. In a further embodiment, the wax has a density greater than 0.94 g/cm3.
The carrier may comprise two or more embodiment described herein.
In an embodiment, the additive blend includes from 1 wt % to 99 wt % of two or more additives and from 1 wt % to 99 wt % of the carrier. Weight percentage is based on a total weight of the additive blend.
In an embodiment, the additive blend includes a peroxide, a catalyst, a silane, a metal deactivator, an antioxidant, a UV stabilizer, a voltage stabilizer, and combinations thereof. In a further embodiment, the additive blend includes the carrier.
In an embodiment, the additive blend includes from 60 wt %, or 70 wt %, or 80 wt % to 90 wt %, or 96 wt % silane; from 1 wt %, or 2 wt %, or 5 wt %, or 8 wt % to 10 wt %, or 15 wt %, or 20 wt % peroxide; and from 1 wt %, or 2 wt %, or 3 wt % to 4 wt %, or 5 wt %, or 8 wt % catalyst. In a further embodiment, the additive blend includes from 70 wt % to 96 wt % silane, from 1 wt % to 10 wt % peroxide, and from 1 wt % to 5 wt % catalyst.
In an embodiment, the additive blend includes a peroxide, a curing coagent, a flame retardant, a water tree retardant, an antioxidant, a UV stabilizer, a voltage stabilizer, and combinations thereof. In a further embodiment, the additive blend includes the carrier.
In an embodiment, the additive blend includes from 50 wt %, or 60 wt %, or 70 wt % to 80 wt %, or 90 wt % or 99 wt % carrier and from 50 wt %, or 40 wt %, or 30 wt % to 20 wt %, 10 wt %, or 1 wt % curing coagent. In a further embodiment, the additive blend includes from 50 to 99 wt %, or from 70 to 80 wt % carrier and from 50 to 1 wt %, or from 30 to 20 wt % curing coagent. Weight percentage is based on the total weight of the additive blend.
A portion of the additive or additive blend may or may not be absorbed into the body 20 through the channel 30. A portion of the additive or additive blend may or may not be adsorbed on the channel surface. In an embodiment, a portion of the additive is absorbed into the body 20 through the channel 30 and a portion of the additive (or additive blend) is adsorbed on the channel surface. The term “absorption,” and derivatives thereof (i.e., “absorbed”), as used herein, is the assimilation of molecular species of the additive throughout the bulk (i.e., within), the body 20. The term “adsorption,” and derivatives thereof (i.e., “adsorbed”), as used herein, is the accumulation of the molecular species of the additive at the body surface rather than within the bulk of the body 20.
The additive may comprise two or more embodiment described herein.
Pellet Dimensions
The pellet 10 has a channel diameter-to-body diameter (CBD) ratio. The term, “channel diameter-to-body diameter (or “CBD”) ratio”, as used herein, refers to the result obtained by dividing the channel diameter by the body diameter (i.e., the CBD is the quotient of the channel diameter and the body diameter). For example when the channel diameter is 2.0 mm and the body diameter is 7.0 mm, the CBD ratio is 0.29. In an embodiment, the CBD ratio is from 0.03, or 0.05, or 0.07, or 0.11 to 0.13, or 0.15, or 0.2, or 0.25, or 0.3, or 0.35, or 0.4, or 0.45, or 0.5. In a further embodiment, the CBD ratio is from 0.03 to 0.5, or from 0.05 to 0.45, or from 0.05 to 0.25, or from 0.05 to 0.15, or from 0.11 to 0.15.
In an embodiment: (i) the length 35 is from 0.4 mm, or 0.8 mm, or 1 mm, or 1.2 mm, or 1.4 mm, or 1.5 mm, or 1.6 mm, or 1.7 mm to 1.9 mm, or 2 mm, or 2.2 mm, or 2.5 mm, or 3 mm, or 3.3 mm, or 3.5 mm, or 4 mm; (ii) the body diameter 40 is from 0.7 millimeters (mm), or 0.8 mm, or 0.9 mm, or 1.0 mm, or 1.5 mm to 3.7 mm, or 4.0 mm, or 4.2 mm, or 4.6 mm, or 5.0 mm; and (iii) the channel diameter 45 is from 0.10 mm, or 0.13 mm, or 0.15 mm, or 0.18 mm to 0.3 mm, or 0.4 mm, or 0.5 mm, or 0.6 mm, or 0.8 mm or 1 mm, or 1.6 mm, or 1.8 mm. In a further embodiment: (i) the length 35 is from 0.4 to 4 mm, or from 0.8 to 3.5 mm, or from 1 to 3.5 mm, or from 1.4 to 2.5 mm, or from 1.5 to 1.9 mm; (ii) the body diameter 40 is from 0.7 to 5.0 mm, or from 0.8 to 4.2 mm, or from 1.0 to 4.0 mm; and (iii) the channel diameter 45 is from 0.10 to 1.8 mm, or from 0.15 to 1.6 mm, or from 0.18 to 1 mm, or from 0.18 to 0.8 mm, or from 0.18 to 0.6 mm.
Returning to
A second orifice 60 is located in the center of a second face 65. The second orifice 60 is circular in shape, or generally circular in shape, and opens into the channel 30. The second orifice 60 has an area that is a function of the channel diameter 45. It is understood that the area of the second orifice 60 is a void space and the first orifice 60 does not have a surface. The second face 65 and the second orifice 60 form concentric circles that are bisected by the axis of symmetry A. The second face 65 has a surface that does not include the second orifice 60. In other words, the second face 65 has the shape of a flat ring.
The first face 55 has a “first surface area” that is the product of the expression (0.25×π×[(the body diameter 40)2−(the channel diameter 45)2]). The second face 65 has a “second surface area” that is the product of the expression (0.25×n×[(the body diameter 40)2−(the channel diameter 45)2]). The surface area of the first face 55 is equal to the surface area of the second face 65.
The body 20 has a body surface that includes a “facial surface.” The facial surface includes the first face 55 and the second face 65. The facial surface has a “facial surface area” that is the sum of the surface area of the first face 55 and the surface area of the second face 65. The facial surface area is the product of the expression 2×(0.25×n×[(the body diameter 40)2−(the channel diameter 45)2]).
The channel 30 has a channel surface 75 including a “channel surface area.” The channel surface area is the product of the expression (n×the channel diameter 45×the length 35). In an embodiment, the channel surface area is from 0.5 mm2, or 1 mm2, or 2 mm2, or 3 mm2 to 6 mm2, to 7 mm2, or 8 mm2, or 9 mm2, or 10 mm2, or 11 mm2. In a further embodiment, the channel surface area is from 0.5 to 11 mm2, or from 1 to 9 mm2, or from 1 to 8 mm2, or from 2 to 8 mm2.
The pellet 10 has a surface area that is the sum of the body surface area and the channel surface area. In an embodiment, the pellet surface area is from 4 mm2, or 15 mm2, or 25 mm2, or 30 mm2, or 35 mm2 to 40 mm2, or 45 mm2, or 50 mm2, or 60 mm2, or 70 mm 2, or 80 mm2. In a further embodiment, the pellet surface area is from 15 to 80 mm2, or from 30 to 60 mm2, or from 35 to 50 mm2.
In an embodiment, (i) the length 35 is from 0.4 mm, or 0.8 mm, or 1 mm, or 1.2 mm, or 1.4 mm, or 1.5 mm, or 1.6 mm, or 1.7 mm to 1.9 mm, or 2 mm, or 2.2 mm, or 2.5 mm, or 3 mm, or 3.3 mm, or 3.5 mm, or 4 mm; (ii) the body diameter 40 is from 0.7 mm, or 0.8 mm, or 0.9 mm, or 1.0 mm, or 1.5 mm to 3.7 mm, or4.0 mm, or 4.2 mm, or4.6 mm, or 5.0 mm; (iii) the pellet surface area is from 4 mm2, or 15 mm2, or 25 mm2, or 30 mm2, or 35 mm2 to 40 mm2, or 45 mm2, or 50 mm2, or 60 mm2, or 70 mm2, or 80 mm2 and (iv) the CBD ratio is from 0.03, or 0.05, or 0.07, or 0.11 to 0.13, or 0.15, or 0.2, or 0.25, or 0.3, or 0.35, or 0.4, or 0.45, or 0.5. In a further embodiment, (i) the length 35 is from 0.4 to 4 mm, or from 0.8 to 3.5 mm, or from 1 to 3.5 mm, or from 1.4 to 2.5 mm, or from 1.5 to 1.9 mm; (ii) the body diameter 40 is from 0.7 to 5.0 mm, or from 0.8 to 4.2 mm, or from 1.0 to 4.0 mm; (iii) the pellet surface area is from 15 to 80 mm2, or from 30 to 60 mm2, or from 35 to 50 mm2 and (iv) the CBD ratio is from 0.03 to 0.5, or from 0.05 to 0.45, or from 0.05 to 0.25, or from 0.05 to 0.15, or from 0.11 to 0.15.
The term, “standard pellet,” as used herein, refers to a pellet without a channel that is otherwise identical to the pellet 10 of the preset disclosure, i.e., the standard pellet has the same body diameter 40 and the same body length 35 as the pellet 10 and the standard pellet is made of the same polymeric material as the body 20 of the pellet 10. In an embodiment, the surface area of pellet 10 is greater than the surface area of a standard pellet. A ratio of the pellet surface area-to-standard pellet surface area is termed the “PSP ratio.” In an embodiment the PSP ratio is from 1.02, or 1.03, or 1.05, or 1.07 to 1.09, or 1.1, or 1.11, or 1.12, or 1.15, or 1.2, or 1.4. In a further embodiment the PSP ratio is from 1.02 to 1.4, or from 1.05 to 1.15, or from 1.05 to 1.11.
The pellet 10 has an channel surface area-to-body surface area (CSBS) ratio. The term, “channel surface area-to-body surface area (or “CSBS”) ratio”, as used herein, refers to the result obtained by dividing the channel surface area by the body surface area (i.e., the CSBS is the quotient of the channel surface area by the body surface area). For example when the channel surface area is 2.0 mm2 and the body surface area is 7.0 mm2, the CSBS ratio is 0.29. In an embodiment, the CSBS ratio is from 0.02, or 0.03, or 0.06, or 0.10, or 0.13 to 0.15, or 0.18, or 0.21, or 0.23, or 0.25, or 0.3. In a further embodiment the CSBS ratio is from 0.02 to 0.3, or from 0.03 to 0.25, or from 0.03 to 0.23, or from 0.03 to 0.21, or from 0.03 to 0.18.
In an embodiment, (i) the length 35 is from 0.4 mm, or 0.8 mm, or 1 mm, or 1.2 mm, or 1.4 mm, or 1.5 mm, or 1.6 mm, or 1.7 mm to 1.9 mm, or 2 mm, or 2.2 mm, or 2.5 mm, or 3 mm, or 3.3 mm, or 3.5 mm, or 4 mm; (ii) the body diameter 40 is from 0.7 mm, or 0.8 mm, or 0.9 mm, or 1.0 mm, or 1.5 mm to 3.7 mm, or 4.0 mm, or 4.2 mm, or 4.6 mm, or 5.0 mm; (iii) the pellet surface area is from 4 mm2, or 15 mm2, or 25 mm2, or 30 mm2, or 35 mm2 to 40 mm2, or 45 mm2, or 50 mm2, or 60 mm2, or 70 mm2, or 80 mm2 and (iv) the CSBS ratio is from 0.02, or 0.03, or 0.06, or 0.10, or 0.13 to 0.15, or 0.18, or 0.21, or 0.23, or 0.25, or 0.3. In a further embodiment, (i) the length 35 is from 0.4 to 4 mm, or from 0.8 to 3.5 mm, or from 1 to 3.5 mm, or from 1.4 to 2.5 mm, or from 1.5 to 1.9 mm; (ii) the body diameter 40 is from 0.7 to 5.0 mm, or from 0.8 to 4.2 mm, or from 1.0 to 4.0 mm; (iii) the pellet surface area is from 15 to 80 mm2, or from 30 to 60 mm2, or from 35 to 50 mm2 and (iv) the CSBS ratio is from 0.02 to 0.3, or from 0.03 to 0.25, or from 0.03 to 0.23, or from 0.03 to 0.21, or from 0.03 to 0.18.
The body 20 is composed of a polymeric material. In an embodiment, the polymeric material is selected from the group consisting of ethylene-based polymer, olefin-based polymer (i.e., a polyolefin polyolefin), crosslinkable polyolefin, polyamide, polyimide, polyester, aromatic polyester, polyacrylonitrile, polycarbonate, polyethylene terephthalate, polysulfide, polysulfone, polyurethane, polyether, polystyrene, polythioether, polytetrafluoroethylene, polyvinyl chloride, phenol-formaldehyde resin, wax, hot melt adhesive, thermoplastic elastomer, thermoplastic polyurethane, rubber, aromatic vinyl polymer, aliphatic vinyl polymer, aromatic alkenyl polymer, and copolymer of the foregoing. In a further embodiment, the polymeric material is selected from an organic polymer, a propylene-based polymer, a thermoplastic polymer, a thermoset polymer, a polymer melt-blend, polymer blends thereof and combinations thereof.
In an embodiment, the polymeric material for body 20 is an ethylene homopolymer.
In an embodiment, the polymeric material for body 20 is an ethylene-based polymer. Non-limiting examples of an ethylene-based polymers include ethylene/α-olefin interpolymers and ethylene/α-olefin copolymers. In an embodiment, the α-olefins include C3-C20 α-olefins and C3-C8 α-olefins. In a further embodiment the α-olefins are linear, branched or cyclic. Nonlimiting examples of suitable α-olefins include propylene, 1-butene, 4-methyl-1-pentene, 1-pentene, 1-hexene, 1-heptene and 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, and 1-octadecene. Nonlimiting examples of suitable cyclic α-olefins include cyclohexene and cyclopentene. Nonlimiting examples of suitable ethylene/α-olefin interpolymers include ethylene/propylene, ethylene/1-butene, ethylene/1-hexene, ethylene/1-octene, ethylene/propylene/1-octene, ethylene/propylene/1-butene, and ethylene/1-butene/1-octene.
In an embodiment, the ethylene-based polymer is an ethylene/α-olefin interpolymer. In an embodiment, the ethylene/α-olefin interpolymer has an α-olefin content from 1 wt %, or 5 wt %, or 10 wt %, or 15 wt %, or 20 wt %, or 25 wt % to 35 wt %, or 45 wt %, or 50 wt %. In a further embodiment, ethylene/α-olefin interpolymer has an α-olefin content of from 1 to 50 wt %, or from 5 to 45 wt %, or from 10 to 40 wt %. Weight percentage is based on a total weight of the interpolymer.
In an embodiment, the ethylene-based polymer is selected from low-density polyethylene (LDPE), linear-low-density polyethylene (LLDPE), very-low-density polyethylene (VLDPE), and combinations of two or more thereof.
In an embodiment, the ethylene-based polymer is an LDPE. In a further embodiment, the LDPE has a density of 0.92 g/cm3 and a melt index (I2) of 2 g/10 min.
In an embodiment, the ethylene-based polymers is an LLDPE.
In an embodiment, the ethylene-based polymer is a blend of two or more ethylene-based polymers described herein. In a further embodiment, the ethylene-based polymers of the blend are blended by an in-reactor process or a post-reactor process.
The polymeric material may comprise two or more embodiments disclosed herein.
Process
The present disclosure provides a process. In an embodiment, the process includes forming a pellet in a melt state. The pellet has a body. The body has a first end and an opposing second end. The body is composed of a polymeric material. The pellet has a channel extending through the body from the first end to the second end. The process includes injecting an additive into the channel. The additive is in a fluid state. The process includes solidifying the pellet, and forming a loaded pellet having additive in the channel.
Formation of the pellet 10 occurs when the olefin-based polymer (which forms the body 20) is in a melt state. The term “melt state,” as used herein, is the olefin-based polymer heated to a molten plastic condition. In other words, the olefin-based polymer in the melt state is extrudable, or otherwise is an extrudate that flows, or is otherwise flowable, through an extruder and/or a die plate. In an embodiment, the olefin-based polymer is an ethylene-based polymer in the melt state. In a further embodiment, the ethylene-based polymer in the melt state is an LDPE in the melt state.
The process includes injecting an additive into the channel 30. The additive can be any additive as previously disclosed herein. The additive is injected into the channel 30 (i) when the additive is in a fluid state and (ii) when the pellet is in the melt state. The term “fluid state,” as used herein, is the additive flows, or otherwise the additive is in a flowable condition.
The process includes solidifying the pellet and the additive to form a loaded pellet. The loaded (and solidified) pellet contains the additive in the channel 30. The additive present in the channel of the loaded pellet may be in the liquid state or may be a solid.
In an embodiment, solidification includes cooling the olefin-based polymer of the body, that is in the melt state, from an elevated temperature to ambient conditions (room temperature).
The process includes forming a loaded pellet. The term, “loaded pellet,” as used herein, refers to a pellet (a hollow pellet), having a quantity of additive located in channel 30. In an embodiment, the additive adheres to the channel surface, such that the additive is retained in—and does not flow freely from—the channel 30.
In an embodiment, the process includes cutting the pellet in the melt state as an extrudate exiting an extruder die plate and into an underwater bath to cool and solidify the pellet and the additive and form the loaded pellet.
In an embodiment, the process includes injecting an additive into the channel. In an embodiment, the additive is in a fluid state. In a further embodiment, the additive includes a material having at least one C—Si—O group. The process includes forming a loaded pellet with the material having at least one C—Si—O group in the channel.
In an embodiment, the additive is an additive blend that includes (i) one or more additives and (ii) a carrier. The carrier is a polyolefin, (such as an ethylene-based polymer, for example).
In an embodiment, the additive is an additive blend including from 60 wt %, or 70 wt %, or 80 wt % to 90 wt %, or 96 wt % silane; from 1 wt %, or 2 wt %, or 5 wt %, or 8 wt % to 10 wt %, or 15 wt %, or 20 wt % peroxide; and from 1 wt %, or 2 wt %, or 3 wt % to 4 wt %, or 5 wt %, or 8 wt % catalyst. In a further embodiment, the additive is an additive blend including from 70 wt % to 96 wt % silane, from 1 wt % to 10 wt % peroxide, and from 1 wt % to 5 wt % catalyst. Weight percentage is based on the total weight of the additive blend.
In an embodiment, the additive is an additive blend including from 50 wt %, or 60 wt %, or 70 wt % to 80 wt %, or 90 wt % or 99 wt % carrier and from 50 wt %, or 40 wt %, or 30 wt % to 20 wt %, 10 wt %, or 1 wt % curing coagent. In a further embodiment, the additive is an additive blend including from 50 to 99 wt %, or from 70 to 80 wt % carrier and from 50 to 1 wt %, or from 30 to 20 wt % curing coagent. Weight percentage is based on the total weight of the additive blend.
The additive blend, (e.g., the additive blend of carrier with silane, peroxide and catalyst dispersed therein), is in a fluid state when injected into the channel 30. In other words, the blend of carrier with silane, peroxide and catalyst dispersed therein is in a molten plastic condition when injected into the channel 30.
In an embodiment, the body has a length and a diameter (body diameter), and the channel has a channel diameter as disclosed above. The process includes forming a loaded pellet having a channel diameter-to-body diameter ratio from 0.05 to 0.15.
In an embodiment, the process includes forming a loaded pellet (with silane in the channel 30) having at least one closed end. In a further embodiment, the process includes forming a loaded pellet (with silane in the channel) having two closed ends.
In an embodiment, the pellet 10 is produced as disclosed in co-pending application ______ (attorney docket No. 82430-WO-PCT), filed on ______, the entire contents of which is incorporated by reference herein.
By way of example, and not limitation, some embodiments of the present disclosure will now be described in detail in the following Examples.
The raw materials used to formulate the Inventive Examples (“IE”) are provided in Table 1 below.
Comparative Sample 1 (CS-1) and Inventive Examples 1-8 (IE-1 to IE-8) are produced with XUS 38658.00 as the extrudate and the process conditions listed in Table 2. The extrusion process uses a Coperion ZSK-26 twin-screw extruder and a loss-in-weight feeder (K-Tron model KCLQX3). The fluid 50 (e.g., air or N2) is injected into the extrudate using the die assembly disclosed in co-pending application ______ (attorney docket No. 82430-WO-PCT), filed on ______, the entire contents of which is incorporated by reference herein. A Gala underwater rotating blade apparatus forms the pellets. The extruder is equipped with 26 millimeter (mm) diameter twin-screws and 11 barrel segments, 10 of which are independently controlled with electric heating and water cooling. The length to diameter ratio of the extruder is 44:1. A light-intensity screw design is used in order to minimize the shear heating of polymer melt.
Fluid-filled pellets (IE-1 to IE-8) are produced with injection of nitrogen gas into the extrudate as listed in Table 3. IE-1 through IE-6 are produced using a nitrogen flow rate of 10 ml/min and a nitrogen pressure between 34 kPag (5 psig) and 410 kPag (60 psig). IE-7 and IE-8 are produced using a nitrogen flow rate of 50 ml/min and a nitrogen pressure of 69 kPag (10 psig).
The dimensions of the pellets formed from process conditions IE-1 to IE-8 from Table 2 are imaged with optical microscopy. The results of the optical microscopy of pellets IE-1 to IE-8 are listed in Table 3.
Inventive Examples 9-20 (IE-9 to IE-20) are produced with the extrusion process conditions listed in Table 4 below. IE-9 to IE-20 are produced using the same process described above with the exception that an additive—silicone oil—is injected into the extrudate using the die assembly disclosed in co-pending application ______ (attorney docket No. 82430-WO-PCT), filed on ______, the entire contents of which is incorporated by reference herein. The silicone oil is injected at the pressures listed in Table 4 to produce loaded pellets.
The dimensions of the loaded pellets (with the additive silicone oil in the channel), formed from process conditions IE-9 to IE-20 from Table 4 are imaged with optical microscopy. The results of the optical microscopy of loaded pellets IE-9 to IE-20 are listed in Table 5 below.
It is specifically intended that the present disclosure not be limited to the embodiments and illustrations contained herein, but include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as come with the scope of the following claims.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2019/080378 | 3/29/2019 | WO | 00 |
