PROCESS FOR PRODUCING A RETICULATED ARTICLE

Abstract

The present disclosure provides a process. In an embodiment, the process includes providing an apparatus. The apparatus includes (A) a passageway with an interior for receiving a first flow stream (FFS1) comprising a melted polymeric composition, the passageway having an inflow end and an opposing outflow end. The apparatus includes (B) a gear pump assembly having (i) a housing, (ii) a gear chamber in the housing, (iii) an inlet placing the passageway outflow end in fluid communication with the gear chamber, the inlet having a width (lw), (iv) a plurality of intermeshing gears mounted for rotation in the gear chamber, the gears having teeth which engage with each other in the chamber, and (v) an outlet in fluid communication with the gear chamber. The apparatus includes (C) one or more injectors upstream of the gear pump assembly for adding a second fluid into the first flow stream. The second fluid is composed of an optional radically graftable species, an optional cure agent, and a peroxide. The peroxide has an activation temperature. The process includes introducing the second fluid from each injector into the FFS1 at a location upstream of the inlet and feeding the FFS1 and the second fluid into the inlet. The process includes mixing, in the gear chamber, the second fluid with FFS1 to form a mixed fluid flowstream (mFFS), and discharging the mFFS from the outlet and into a die head to form a shaped article. The process includes passing the shaped article through a curing chamber, and crosslinking, in the curing chamber, the polymer to form a crosslinked shaped article (CSA).

Description

1 / 31 PROCESS FOR PRODUCING A NETWORKED ARTICLE BACKGROUND

[001] Extruders and static mixers are commonly used to combine, or otherwise mix, two or more viscous materials, such as molten polymer streams. A molten polymer stream is generally highly viscous, and the flow of the molten polymer stream in the process is typically laminar, without a natural mixing mechanism. The highly viscous nature of molten polymer streams makes the addition and mixing of small quantities of low-viscosity fluid products (additives) problematic. Although an extruder (twin-screw or single-screw with mixing element) can be used to mix a lower-viscosity liquid additive into a molten polymer stream, extruders are difficult to scale up, and production costs increase rapidly when production capacity and extruder size are desired.

[002] Employing a static mixer has the disadvantage of increasing capital costs. A static mixer impedes flow and consequently poses the risk of introducing significant pressure drop in a molten polymer flow production process. The pressure drop resulting from the addition of a static mixer in a flow process can lead to potential dead zones in the production stream. Dead zones can lead to long-term degradation of the molten polymer flow process, especially with reactive systems.

[003] The technique recognizes the need for alternative mixing processes for molten polymer streams that avoid static extruders and / or mixers. SUMMARY Petition 870250079651, dated 05 / 09 / 2025, page 13 / 53 2 / 31

[004] The present disclosure provides a process. In one embodiment, the process includes providing an apparatus. The apparatus includes (A) a passage with an interior for receiving a first flow stream (FFS1) comprising a molten polymeric composition, wherein the passage has an inlet end and an opposite flow end. The apparatus includes (B) a gear pump assembly having (i) a housing, (ii) a gear chamber in the housing, (iii) an inlet that places the flow end of the passage in fluid communication with the gear chamber, wherein the inlet has a width (Iw), (iv) a plurality of interlocking gears mounted for rotation in the gear chamber, wherein the gears have teeth that engage with each other in the chamber, and (v) an outlet in fluid communication with the gear chamber.The apparatus includes (C) one or more injectors upstream of the gear pump assembly to add a second fluid to the first flow stream. The second fluid is composed of an optional radically graftable species, an optional curing agent, and a peroxide. The peroxide has an activation temperature. The process includes introducing the second fluid from each injector into the FFS1 at a location upstream of the inlet and feeding the FFS1 and the second fluid to the inlet. The process includes mixing, in the gear chamber, the second fluid with FFS1 to form a mixed fluid flow stream (mFFS) and discharging the mFFS from the outlet into a die head to form a molded article. The process includes passing the molded article through a curing chamber and crosslinking, in the curing chamber, the polymer to form a crosslinked shaped article (“CSA”). BRIEF DESCRIPTION OF THE DRAWINGS

[005] Figure 1 is a cross-sectional view of an apparatus with a gear pump according to an embodiment of the present disclosure. Petition 870250079651, dated 05 / 09 / 2025, page 14 / 53 3 / 31

[006] Figure 2 is an enlarged view of Area 2 from Figure 1.

[007] Figure 3A is a cutaway perspective view of the apparatus of Figure 1, showing the fluid blades according to an embodiment of the present disclosure.

[008] Figure 3B is a cross-sectional view of Area 3B from Figure 3A.

[009] Figure 4A is a cross-sectional view of the apparatus in Figure 1 indicating alternative locations for the injectors in the apparatus passage.

[0010] Figures 4B-4E are cross-sectional views of the apparatus showing flow and mixing profiles corresponding to the injector locations in Figure 4A. Figures 4B-4E also show a cross-sectional view of the resulting mixed fluid flow stream and the corresponding CoV value for each respective flow and mixing profile.

[0011] Figure 5 is a side elevation view of an apparatus with a tapered section according to an embodiment of the present disclosure.

[0012] Figure 6A is a front elevation view of an injection duct in a vertical orientation according to an embodiment of the present disclosure.

[0013] Figure 6B is a front elevation view of an injection duct in a horizontal orientation according to an embodiment of the present disclosure.

[0014] Figures 7A, 7B and 7C are each a perspective view of the interlocking gears according to the respective embodiments of this disclosure.

[0015] Figure 8 is a perspective view of a double helical (herringbone) gear.

[0016] Figure 9 is an additive concentration profile for a spur gear (0° helix), a helical gear (7° helix), a helical gear (30° helix), and a double helical gear. Petition 870250079651, dated 05 / 09 / 2025, p. 15 / 53 4 / 31 (herringbone) in (A) injection angle of 0° and (B) injection angle of 90°. DEFINITIONS

[0017] Any reference to the Periodic Table of Elements refers to that as published by CRC Press, Inc., 1990–1991. The reference to a group of elements in that table is by the new notation for numbered groups.

[0018] For purposes of United States patent practice, the content of any patent, patent application or publication referenced is incorporated by reference in its entirety (or its U.S. equivalent is incorporated by reference), especially with respect to the disclosure of definitions (provided there is no inconsistency with any definitions specifically provided in this disclosure).

[0019] The numerical ranges disclosed here include all values ​​within, and including, the lower and upper values. 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., the range 1 to 7 above includes subranges 1 to 2; 2 to 6; 5 to 7; 3 to 7; 5 to 6; etc.).

[0020] Unless otherwise indicated, where implied by the context or where 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.

[0021] The terms “blend” or “polymer blend,” as used, refer to a mixture of two or more polymers. A blend may or may not be miscible (not separated into phases at the molecular level). A blend may or may not be separated into phases. A blend may or may not contain one or more domain configurations, as determined by transmission electron spectroscopy, light scattering, X-ray scattering, and Petition 870250079651, dated 05 / 09 / 2025, page 16 / 53 5 / 31 other methods known in the art. Blending can be carried out by physically mixing the two or more polymers at the macro level (e.g., melt blending or compounding resins) or at the micro level (e.g., simultaneous forming within the same reactor).

[0022] The term “composition” refers to a mixture of materials that constitute the composition, as well as reaction products and decomposition products formed from the materials of the composition.

[0023] 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 specifically disclosed. For the avoidance of doubt, all compositions claimed by the use of the term “comprising” or “comprising” may include any additive, adjuvant or additional compound, polymeric or not, unless stated otherwise. Conversely, the term “essentially consisting of” excludes from the scope of any subsequent citation any other component, step or procedure, except those that are not essential for operability. The term “consisting of” excludes any component, step or procedure not specifically outlined or listed. The term “or”, unless otherwise indicated, refers to the members listed individually as well as in any combination.

[0024] Ethylene-based polymer (interchangeably called polyethylene) is a polymer comprising a major amount (> 50 mol%) of units derived from ethylene monomer. This includes polyethylene homopolymers or copolymers (i.e., units derived from two or more comonomers). Common forms of polyethylene known in the art include low-density polyethylene (LDPE); linear low-density polyethylene (LLDPE); polyethylene Petition 870250079651, dated 05 / 09 / 2025, page 17 / 53 6 / 31 ultra-low density polyethylene (ULDPE); linear low-density polyethylene produced with a single-site catalyst, including both linear and substantially linear low-density (mLLDPE) resins; ethylene-based plastomers (POP) and ethylene-based elastomers (POE); medium-density polyethylene (MDPE); and high-density polyethylene (HOPE). These polyethylene materials are generally known in the art; however, the following descriptions may be helpful in understanding the differences between some of these different polyethylene resins.

[0025] The term “LDPE” may also be referred to as “high-pressure ethylene polymer” or “highly branched polyethylene” and should mean that the polymer is partially or fully homopolymerized or copolymerized in autoclaves or tubular reactors at pressures above 14,500 psi (100 MPa) using free radical initiators such as peroxides (see, for example, US patent 4,599,392, which is incorporated herein by reference). LDPE resins typically have a density in the range of 0.916 to 0.935 g / cm3.

[0026] The term “LLDPE” includes resin produced using traditional Ziegler-Natta catalytic systems and chromium-based catalytic systems, as well as single-site catalysts, including but not limited to substituted mono- or bis-cyclopentadienyl catalysts (typically called metallocene catalysts), restricted geometry catalysts, pyridylamine catalysts, phosphinimine catalysts, and polyvalent aryloxyether catalysts (typically called bisphenylphenoxy catalysts), and includes linear, substantially linear, or heterogeneous polyethylene copolymers or homopolymers. LLDPEs contain fewer long-chain branches than LDPEs and include the substantially linear ethylene polymers that are further defined in U.S. Patent No. 5,272,236. Petition 870250079651, dated 05 / 09 / 2025, page 18 / 53 7 / 31 No. 5,278,272, in US Patent No. 5,582,923 and in US Patent No. 5,733,155; homogeneously branched linear ethylene polymer compositions, such as those in US Patent No. 3,645,992; heterogeneously branched ethylene polymers, such as those prepared according to the process disclosed in US Patent No. 4,076,698; and / or blends thereof (such as those disclosed in US Patent No. 3,914,342 or US Patent No. 5,854,045). LLDPEs can be produced via gas-phase, solution-phase, or slurry polymerization, or any combination thereof, using any type of reactor or reactor configuration known in the art.

[0027] The term “MDPE” refers to polyethylenes that have densities of 0.926 to 0.935 g / cm3. “MDPE” is typically produced using chromium or Ziegler-Natta catalysts or using single-site catalysts including, but not limited to, substituted mono- or biscyclopentadienyl catalysts (typically called metallocene catalysts), restricted geometry catalysts, pyridylamine catalysts, phosphinimine catalysts and polyvalent aryloxyether catalysts (typically called bisphenylphenoxy catalysts) and typically have a molecular weight distribution (MWD) greater than 2.5.

[0028] The term “HDPE” refers to polyethylenes with densities greater than about 0.935 g / cm3 and up to about 0.980 g / cm3, which are generally prepared with Ziegler-Natta catalysts, chromium catalysts or single-site catalysts including, but not limited to, substituted mono- or bis-cyclopentadienyl catalysts (typically called metallocenes), restricted geometry catalysts, pyridylamine catalysts, phosphinimine catalysts and polyvalent aryloxyether catalysts (typically called bisphenylphenoxy).

[0029] The term “ULDPE” refers to polyethylenes that have densities of 0.855 to 0.912 g / cm3, which are generally prepared with catalysts. Petition 870250079651, dated 05 / 09 / 2025, p. 19 / 53 8 / 31 Ziegler-Natta catalysts, chromium catalysts, or single-site catalysts including, but not limited to, substituted mono- or biscyclopentadienyl catalysts (typically called metallocene catalysts), restricted geometry catalysts, pyridylamine catalysts, phosphinimine catalysts, and polyvalent aryloxyether catalysts (typically called bisphenylphenoxy catalysts). ULDPEs include, but are not limited to, polyethylene plastomers (ethylene-based) and polyethylene elastomers (ethylene-based). Polyethylene elastomers and plastomers (ethylene-based) generally have a density of 0.855 to 0.912 g / cm³.

[0030] An “olefin” is an unsaturated aliphatic hydrocarbon that has a carbon-carbon double bond.

[0031] An “olefin-based polymer” (interchangeably referred to as a “polyolefin”) is a polymer that contains a major weight percentage of polymerized olefin monomer (based on the total amount of polymerizable monomers) and may optionally contain at least one comonomer. Non-limiting examples of olefin-based polymers include ethylene-based polymers and propylene-based polymers.

[0032] The term “polymer” or “polymeric material,” as used herein, refers to a compound prepared by polymerization of monomers, whether of the same type or of a different type, which in the polymerized form provides the multiple and / or repeating “units” or “mer units” that constitute a polymer. The generic term polymer thus encompasses the term homopolymer, generally used to refer to polymers prepared from only one type of monomer, and the term copolymer, generally used to refer to polymers prepared from at least two types of monomers. It also encompasses all forms of copolymer, for example, random, block, etc. The terms “ethylene / α-olefin polymer” and “propylene / α-olefin polymer” are indicative of copolymer, as described above, prepared from the polymerization of Petition 870250079651, dated 05 / 09 / 2025, page 20 / 53 9 / 31 ethylene or propylene, respectively, and one or more additional polymerizable α-olefin monomers. It is noted that, although a polymer is often referred to as being “produced from” one or more specified monomers, “based on” a specified monomer or type of monomer, “containing” a specified monomer content or similar, in this context, the term “monomer” is understood to refer to the polymerized remainder of the specified monomer and not to the unpolymerized species. In general, the polymers in the present invention are referred to as being based on “units” that are the polymerized form of a corresponding monomer.

[0033] A “propylene-based polymer” (interchangeably referred to as “polypropylene”) is a polymer containing more than 50 mole percent of polymerized propylene monomer (based on the total amount of polymerizable monomers) and may optionally contain at least one comonomer. Propylene-based polymers include propylene homopolymers and propylene copolymers (i.e., propylene-derived units and one or more comonomers). The terms “propylene-based polymer” and “polypropylene” may be used interchangeably. A non-limiting example of a propylene-based polymer (polypropylene) is a propylene / α-olefin copolymer with at least one C2 or C4-C10 α-olefin comonomer. Testing methods

[0034] Degree of mixing. The degree of mixing is quantified by the coefficient of variation (CoV) of the local concentration of the second fluid (F2) relative to the first flow stream (FFS1) in a given cross-sectional plane. The CoV defined in Equation 1 is calculated in a cross-sectional plane normal to the average flow velocity, where C is the concentration at position re and te is the average concentration at time te. Petition 870250079651, dated 05 / 09 / 2025, page 21 / 53 10 / 31 Equation 1 σ CoV = C Equation 2n C = Average concentration = — / CínÍ=1 Equation 3 n σ = Des via paarao = I----------n

[0035] where is the sample size, which is the number of computational fluid dynamics fluid elements in the cross-sectional plane, and is the concentration in the i-th fluid element. In general, the smaller the CoV value, the greater the degree of mixing.

[0036] Density is measured according to ASTM D792, Method B. The result is recorded in grams per cubic centimeter (g / cc or g / cm3). The density of the fluid flow stream (in Table 1) is measured according to ASTM D 792. The result is recorded in grams (g) per cubic centimeter (g / cc or g / cm3).

[0037] The melt index (I? or MI (melt index)) is measured according to ASTM D-123 8 method, at 190 °C at 2.16 kg. Values ​​are reported in g / 10 min, which corresponds to grams eluted every 10 minutes.

[0038] “Viscosity” refers to the resistance of a fluid to deformation by shear stress or tensile stress. For the purposes of this descriptive report, viscosity is measured at 130 °C using a Brookfield viscometer, as measured in accordance with ASTM D 445. Results are reported in centipoise (cP). DETAILED DESCRIPTION

[0039] The present disclosure provides a process. In one embodiment, the process includes providing an apparatus. The apparatus includes (A) Petition 870250079651, dated 05 / 09 / 2025, p. 22 / 53 11 / 31 a passage with an interior to receive a first flow stream (FFS1). FFS1 is a fused polymeric composition. The passage has an inlet end and an opposite flow end. The apparatus includes (B) a gear pump assembly. The gear pump assembly includes (i) a housing, (ii) a gear chamber in the housing, (iii) an inlet placing the flow end of the passage in fluid communication with the gear chamber. The inlet has a width (Iw). The gear pump assembly also includes (iv) a plurality of interlocking gears mounted for rotation in the gear chamber. The gears have teeth that engage with each other in the chamber. The gear pump assembly also includes (v) an outlet in fluid communication with the gear chamber.The apparatus further includes (C) one or more injectors upstream of the gear pump assembly to add a second fluid to the first flow stream. The second fluid includes (i) an optional radically graftable species and (ii) a peroxide and, optionally, a curing agent (and / or optional burn retardant). The peroxide has an activation temperature. The process includes introducing the second fluid from each injector into FFS1 at a location upstream of the inlet; feeding FFS1 and the second fluid into the inlet and mixing, in the gear chamber, the second fluid with FFS1 to form a mixed fluid flow stream (mFFS). The process further includes discharging the mFFS from the outlet into a die head to form a molded article. The process includes passing the molded article through a curing chamber and crosslinking, in the curing chamber, the polymer to form a crosslinked shaped article (CSA).

[0040] The process includes providing an apparatus. The apparatus includes (A) a passage with an interior to receive a first flow stream (FFS1). The passage has an opening at one inlet end and a Petition 870250079651, dated 05 / 09 / 2025, page 23 / 53 12 / 31 opening at an opposite outlet end. The apparatus includes (B) a gear pump assembly. The gear pump assembly includes (i) a housing, (ii) a gear chamber in the housing, (iii) an inlet that places the passage in fluid communication with the gear chamber, the inlet having a width (Iw), (iv) a plurality of interlocking gears mounted for rotation in the gear chamber, the gears having teeth that engage with each other in the chamber, and (v) an outlet in fluid communication with the gear chamber. The apparatus includes (C) one or more injectors located upstream of the gear pump assembly to add a second fluid to the first flow stream. In one embodiment, each injector is located at a distance of at least half a gear diameter upstream from the inlet. In one embodiment, each injector has an elongated conduit that extends into the interior of the passage.The process involves introducing a second fluid from each respective elongated conduit into the FFS1 at a location at least half a gear diameter upstream of the inlet. The process includes feeding the FFS1 and the second fluid into the inlet, mixing the second fluid with the FFS1 in the gear chamber to form a mixed fluid flow stream (mFFS), and discharging the mFFS from the outlet.

[0041] The description is given here with specific reference to the accompanying drawings, which illustrate the features and operation of the embodiments of the present disclosure, but which are not intended to limit its scope. In the Figures (unless otherwise indicated), similar numerals are used to designate similar elements of the apparatus.

[0042] Figures 1 and 2 illustrate a mixing apparatus 10 that has a gear pump 12, a passage 14 and an outlet cylinder 16. The passage 14 is an annular body with a substantially uniform diameter, or a uniform diameter, along its length. A Petition 870250079651, dated 05 / 09 / 2025, page 24 / 53 13 / 31 passage 14 may or may not include a tapered section 15 as will be disclosed below. When the tapered section is not present, passage 14 has a substantially uniform diameter, or a uniform diameter, along the length of passage 14.

[0043] Apparatus 10 includes a gear pump assembly. A "gear pump" is a positive displacement pump that moves a fluid (or one or more fluids) by repeatedly encircling a fixed volume using interlocking gears in a housing, the interlocking gears transferring the fluid mechanically using a cyclic pumping action. The rotating gears develop a liquid seal with the pump housing and create suction at the pump inlet. The fluid drawn into the pump is enclosed within the cavities of the rotating gears and the fluid is transferred to a discharge outlet.

[0044] Figure 1 shows a cutaway view of the apparatus 10. Figure 1 shows the gear pump assembly 12. The gear pump assembly 12 includes a housing 18 that defines a gear chamber 20. The gear chamber 20 has an inlet 19. The inlet 19 is an opening in the housing 18 that places the passage 14 in fluid communication with the gear chamber 20. The inlet 19 has an inlet width 21. The inlet width 21 is the longest length of the inlet 19 that extends between opposite sides of the housing 18. When the top-to-bottom length of the inlet 19 is not the same length as the side-to-side length for the inlet 19, the inlet width 21 is the greater length among the top-to-bottom length or the side-to-side length. When the inlet 19 has a circular cross-sectional shape, the inlet width 21 is the diameter of the inlet 19.Since the configuration and shape of input 19 can vary, the length of input width 21 can vary accordingly. In other words, a. Petition 870250079651, dated 05 / 09 / 2025, page 25 / 53 14 / 31 entry width 21 may or may not include the aggregate diameters for the interlocking gears 22a and 22b, in addition to the small gap, or small clearance, between each gear and the inner wall of the gear chamber 20. The length, or span, of the entry width 21 is interchangeably called “Iw”.

[0045] Inside the gear chamber 20 resides a plurality of (or two) interlocking gears (interchangeably called gears, or gear (singular)), gear 22a and gear 22b. Each gear 22a, 22b has 24 teeth. The 24 teeth of gear 22a interlock with (or lock with) the 24 teeth of gear 22b. In one embodiment, gear 22a has the same size and shape as gear 22b, so that gear 22a and gear 22b each have a gear diameter 25 with the same length.The “gear diameter” (also known as the “outer gear diameter”), as used herein, is the length of a straight-line segment that starts from a gear tooth, passes through the axis of rotation, and extends through the gear to an opposite gear tooth and defines an outermost gear diameter, as shown by gear diameter 25, gear diameter 25 being a straight-line segment shown in Figure 1. Gear diameter 25 is interchangeably referred to as “Gd”. The term “gear diameter” is interchangeably referred to as “outer gear diameter” and / or “pitch diameter”. Alternatively, gear 22a may have a different size and / or shape than gear 22b. Each gear 22a, 22b is supported by a separate shaft (not shown). Generally, one gear is driven by a motor, and this drives the other gear (the pulley).In one embodiment, both axes can be driven by motors. The axes are supported by bearings on each side of the housing. Petition 870250079651, dated 05 / 09 / 2025, p. 26 / 53 15 / 31 Each shaft rotates a corresponding gear around an axis of rotation. Gear 22a rotates around axis of rotation 26a, gear 22b rotates around axis of rotation 26b. As each gear 22a, 22b rotates around its respective axis of rotation, the teeth 24 mesh, interlock, engage, or otherwise interlock with each other. As the rotation of the gears continues, the teeth disengage from each other.

[0046] In one embodiment, each gear has a helix angle. A “helix angle,” as used herein, is the angle between the axis of rotation of the gear and a line tangent to one of the teeth, as seen from an elevated view of the gear. The helix angle can be from 0° to 45°. In another embodiment, the helix angle for gears 22a, 22b is from 0° to 5°.

[0047] In one embodiment, each gear is a double helical (herringbone) gear. A “double helical (herringbone) gear” is a gear with gear teeth having an alpha helix angle from one end of the gear cylinder to the middle of the gear cylinder and then a 360-alpha angle from the middle of the gear cylinder to the other end of the gear cylinder. The angle is measured from the edge of the helical gear teeth to the axis of the gear cylinder moving clockwise. This creates a “V-pattern” (as shown in Figure 8) for the gear teeth on the gear cylinder and hence the name “herringbone”.

[0048] The process involves feeding a first fluid flow stream 34 (shaded gray area in Figure 1) into passage 14. Passage 14 has an upstream or inlet end to receive the first fluid flow stream. Passage 14 has a downstream, or flow, end in fluid communication with inlet 19. A “fluid flow stream”, as used herein, is a material that is in a Petition 870250079651, dated 05 / 09 / 2025, page 27 / 53 16 / 31 fluid state and moves, or otherwise flows, like a stream. Fluid flow is distinct from the flow of fine solid particles (sand spill, for example) because fine solid particles (sand particles) are not in a fluid state. Flow is typically induced and sustained by gravity, but other forms of energy or force can be used to induce flow, for example, those resulting from the use of a pump. Non-limiting examples of first-stream fluid flow material (interchangeably called “FFS1”) include polymer in a molten, melted, or otherwise fluid state including polyester, polyamide, polyurethane, polyolefin (polyethylene, polypropylene), poly(ethylene terephthalate), natural rubber, synthetic rubber, EPDM, and combinations thereof. In one embodiment, FFS1 has a viscosity of 0.1 g / 10 min at 1000 g / 10 min, or 0.1 g / 10 min at 100 g / 10 min, or 0.1 g / 10 min at 10 g / 10 min.

[0049] Apparatus 10 includes one or more injectors 50 for introducing a second fluid into FFS1. Apparatus 10 may include one, or two, or three, or four, or five, or six, or more injectors 50. The injectors 50 are located upstream of the gear pump assembly 12. The injectors 50 are in fluid communication with a source for the second fluid, along with piping, valve(s), and pump(s) to supply the second fluid to the injectors 50. The second fluid (interchangeably referred to as “F2”) includes (i) a free radical initiator, such as a peroxide, for example, (ii) an optional radically graftable species, (iii) an optional curing agent. In one embodiment, the second fluid has a viscosity that is lower than the viscosity of FFS1. It is understood that F2 is a fluid and may or may not include solid particles dispersed within it, and that F2 has a lower viscosity than FF1.In a further embodiment, the second fluid has a viscosity of 1 centipoise (cP) to 5000 cP, or 1 cP to 1000 cP, or 1 cP to 100 cP, or 1 cP to 10 cP. Petition 870250079651, dated 05 / 09 / 2025, p. 28 / 53 17 / 31

[0050] Non-limiting examples of suitable free radical initiators include organic initiators such as dicumyl peroxide, di-tert-butyl peroxide, t-butyl perbenzoate, benzoyl peroxide, cumene hydroperoxide, t-butyl peroctoate, methyl ethyl ketone peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, lauryl peroxide, tert-butyl peracetate, and combinations thereof. The free radical initiator (the peroxide) has an activation temperature (or decomposition temperature).

[0051] A variety of radically graftable species can be attached to the polymer composition of FFS1, either individually or as relatively short grafts. These radically graftable species include unsaturated molecules, each containing at least one heteroatom. These radically graftable species include, but are not limited to, silane comonomer, maleic anhydride, dibutyl maleate, dicyclohexyl maleate, diisobutyl maleate, dioctadecyl maleate, N-phenylmaleimide, citraconic anhydride, tetrahydrophthalic anhydride, bromomaleic anhydride, chloromaleic anhydride, nadic anhydride, methylnadic anhydride, alkenylsuccinic anhydride, maleic acid, fumaric acid, diethyl fumarate, itaconic acid, citraconic acid, crotonic acid and the respective ethers, imides, salts and Diels-Alder adducts of these compounds.

[0052] The radically writable species may be a silane comonomer. The silane comonomer with the following formula may be grafted onto the FFS1 polymer composition: where R1 is a hydrogen atom or methyl group; x is 0 or 1 with the condition that when x is 1, n is at least 1; men are independently an integer from 0 to 12 inclusive, or from 1 to 4, and each R2 is independently a hydrolyzable organic group, such as a group Petition 870250079651, dated 05 / 09 / 2025, page 29 / 53 18 / 31 alkoxy groups with 1 to 12 carbon atoms (e.g., methoxy, ethoxy, butoxy), an aryloxy group (e.g., phenoxy), an aryloxy group (e.g., benzyloxy), an aliphatic acyloxy group with 1 to 12 carbon atoms (e.g., formyloxy, acetyloxy, propanoyloxy), amino or substituted amino groups (e.g., alkylamino, arylamino) or a lower alkyl group with 1 to 6 carbon atoms inclusive, provided that no more than one of the three R groups is an alkyl. These silanes can be grafted onto the FFS1 polymer composition by using an appropriate amount of organic peroxide.

[0053] Non-limiting examples of suitable silanes include unsaturated silanes comprising an ethylenically unsaturated hydrocarbyl group, such as a vinyl, allyl, isopropenyl, butenyl, cyclohexenyl or gamma-(meth)acryloxyallyl group, and a hydrolyzable group, such as, for example, a hydrocarbyloxy, hydrocarbonyloxy or hydrocarbylamino group. Non-limiting examples of hydrolyzable groups include methoxy, ethoxy, formyloxy, acetoxy, propionyloxy and alkyl or arylamine groups. In one embodiment, the silane comonomer is selected from vinyl trimethoxysilane (VTMS), vinyl triethoxysilane, vinyl triacetoxysilane, gamma(meth)acryloxypropyltrimethoxysilane or a combination thereof.

[0054] In one embodiment, each injector 50 includes an elongated conduit 52 that extends, penetrates, or otherwise traverses the interior of passage 14. Each elongated conduit 52 traverses a portion or the entire diameter of passage 14, each elongated conduit 52 extending through the interior of passage 14.

[0055] In one embodiment, each elongated conduit 52 includes a plurality of spaced ports 54 extending along the length of one downstream side of each elongated conduit 52. The ports 54 discharge, or otherwise dispense, the second fluid along a length of each elongated conduit 52. In one embodiment, the ports 54 discharge Petition 870250079651, dated 05 / 09 / 2025, p. 30 / 53 19 / 31 a continuous flow of the second fluid along a length of each conduit forming a fluid sheet. A “fluid sheet”, as used herein, is a substantially continuous, or continuous, fluid body composed of the second fluid disposed in FFS1, the fluid sheet body having a length, a width, and a height when FFS1 is viewed from a cross-sectional view downstream of the elongated conduit. Figure 3A is a cutaway perspective view of apparatus 10 with passage 14 and cabinet 18 removed, Figure 3A showing the fluid sheets 60a, 60b formed from the respective injectors 50a, 50b (each having a respective elongated conduit 52 and spaced ports 54). Figure 3A shows each fluid layer 60a, 60b having a corresponding body 62, wherein each body 62 is a continuous volume of F2, and each body 62 has the respective dimensions of a length (L), width (W), and height (H).

[0056] Referring back to Figure 1, in one embodiment, the injectors 50 are located at a distance that is at least half a gear diameter (or 0.5 Gd) upstream of inlet 19. For example, when gear 22a (and / or gear 22b) has a diameter of 32 cm, the distance of half the gear diameter (or 0.5 Gd) is 16 cm. The process involves introducing the second fluid 36 (interchangeably referred to as “F2”) into FFS1 34 at a distance that is at least half a gear diameter, or 0.5 Gd, upstream of inlet 19, or from 1 Gd to 5 Gd, or from 1 Gd to 3 Gd, or from 1.5 Gd to 3 Gd upstream of inlet 19. In one embodiment, the apparatus 10 includes two injectors, the first injector 50a and the second injector 50b, injector 50a being displaced from injection 50b along a passage diameter 56, each injector 50a, 50b (and passage diameter 56) being located at a distance of at least 0.5 Gd upstream of inlet 19, as shown in Figure 1.

[0057] In one embodiment, the length of the input width 21 Petition 870250079651, dated 05 / 09 / 2025, page 31 / 53 20 / 31 is greater than the length of the gear diameter 25. Injectors 50 are located at a distance that is at least the inlet width, Iw, upstream of inlet 19. The process includes the introduction of the second fluid 36 (interchangeably referred to as “F2”) into FFS1 34 at a distance that is at least 1 Iw upstream of inlet 19, or from 1 Iw to 5 Iw, or from 1 Iw to 3 Iw, or from 1.5 Iw to 3 Iw upstream of inlet 19. In one embodiment, the apparatus 10 includes two injectors, the first injector 50a and the second injector 50b, injector 50a being displaced from injection 50b along a passage diameter 56, each injector 50a, 50b (and passage diameter 56) being located at a distance of 1 Iw upstream of inlet 19, as shown in Figure 1.

[0058] In one embodiment, each injector includes a set of a plurality of spaced ports extending along a portion of the passage sidewall (“wall injectors”). The ports are perforated through the sidewall and are in fluid communication with the source for the second fluid, as disclosed in the copendente ussn case filed at (84964-US-PSP), the contents of which are incorporated herein by reference. The wall injectors may be located at a distance that is at least half a gear diameter (or 0.5 Gd) upstream of inlet 19 or located at a distance that is at least the inlet width, Iw, upstream of inlet 19 as disclosed in relation to injectors 50 above.

[0059] The process involves feeding FFS1 and F2 into inlet 19 and mixing F2 36 into FFS1 34 in gear chamber 20. FFS1 34 and F2 36 enter gear chamber 20 from passage 14. The counter-rotating gears 22a, 22b create a suction force in Area 4 trapping, or otherwise pulling, FFS1 and F2 into gear chamber 20. As the counter-rotation of gears 22a, 22b continues, FFS1 and F2 are stretched into a space 38 between teeth 24 and the inner wall of the Petition 870250079651, dated 05 / 09 / 2025, p. 32 / 53 21 / 31 gear chamber 20, as shown by arrows M in Figure 1. With further rotation of the gear, stretching continues and a compression force occurs in space 38, mixing F2 into FFS1. As teeth 24 of gear 22a engage (or re-engage) with teeth 24 of gear 22b in Area 5, the trapped FFS2 that is mixed into FFS1 is expelled from gear chamber 20, out and through outlet 42 as a mixed flow stream 40 (or “mFFS 40”). This “suction-stretch-squeeze-expel” cycle repeats as gears 22a, 22b continue in counter-rotation, with the suction force trapping new quantities of FFS1 34 and F2 36 between the interlocking teeth and the inner wall of the gear chamber, continuing the cycle.

[0060] The process involves discharging mFFS 40 from outlet 42. From outlet 42, mFFS 42 flows to a die head 44 to form a molded article, as shown in Figure 5. Non-limiting examples of suitable die heads include a tube mold and / or a tube extrusion die.

[0061] The process involves passing the molded article through a curing chamber 16 and forming a crosslinked molded article, as shown in Figure 5. The process includes maintaining, during mixing and discharge, the mFFS temperature below the peroxide activation temperature to avoid premature crosslinking or “burning”. As the mFFS is formed by the die head on the molded article, the molded article is pushed by the upstream melt pressure generated by the melt pump through the curing chamber 16. Non-limiting examples of suitable curing chambers include a high-temperature tube (a “high-temperature tube” is a tube or chamber that can be heated above the peroxide activation temperature) and / or a vulcanizing tube. The process involves heating the molded article above the peroxide activation temperature in the curing chamber. Exposure to temperatures above the Petition 870250079651, dated 05 / 09 / 2025, pp. 33 / 53 22 / 31 activation temperature of the peroxide induces crosslinking of the molded article.

[0062] In one embodiment, the second fluid includes a peroxide, a radically graftable species, and an optional curing agent. The process involves discharging mFFS (containing peroxide, radically graftable species, and optional curing agent) from the outlet. From the outlet, the mFFS flows to the die head to form a molded article (containing polymer, peroxide, radically graftable species, and optional curing agent). The process involves passing the molded article through the curing chamber 16. In this embodiment, non-limiting examples of suitable curing chambers include a high-temperature tube, a moisture crosslinking chamber, a sauna, a hot water bath, an ambient condition chamber, and combinations thereof.The process involves grafting, in the curing chamber, the radically graftable species onto the polymer to form a graft polymer and subsequently crosslinking, in the curing chamber, the graft polymer to form a crosslinked graft-shaped article (CgSA).

[0063] In one embodiment, the second fluid includes a peroxide, a radically graftable species, and a curing agent that is a moisture-curing catalyst. The process involves discharging mFFS (containing peroxide, radically graftable species, and moisture-curing catalyst) from the outlet. From the outlet, the mFFS flows to the die head to form a molded article (containing polymer, peroxide, radically graftable species, and moisture-curing catalyst). The process involves passing the molded article through the curing chamber 16, which is a moisture crosslinking chamber, a sauna, a hot water bath, and any combination thereof. The process includes grafting, in the curing chamber, the radically graftable species onto the polymer to form a grafted polymer and subsequently crosslinking the grafted polymer with the moisture-curing catalyst in the curing chamber to form an article. Petition 870250079651, dated 05 / 09 / 2025, p. 34 / 53 23 / 31 in cross-linked graft form (CgSA).

[0064] Without adhering to a specific theory, the Applicant found that introducing the second fluid into FFS1 at a distance that is at least half a gear diameter (or a distance that is at least one Iwa upstream of inlet 19) unexpectedly creates, or otherwise defines, a recirculation zone in passage 14 (or, alternatively, in the tapered section).A “recirculation zone”, as used herein, is a volume portion in passage 14 (or a volume portion in the tapered section) with a downstream end defined by a plane encompassing inlet 19 and an upstream end defined by a plane encompassing elongated conduits located at least half a gear diameter (0.5 Ga) away and upstream from inlet 19 (or located at a distance of at least one lwa away and upstream from inlet 19); wherein the rotation of gears 22a, 22b creates in the volume portion (i) a laminar flow stream of FFS1 and the second fluid and (ii) a vortex flow stream of FFS1 and the second fluid.The recirculation zones perform two actions: (1) the recirculation zone moves the second inlet fluid blades (F2) to a low pressure zone at an apex of the gear interlock zone; and (2) the recirculation zone intensifies the mixing of the second fluid blades (F2), where a portion of the second fluid F2 initially mixes in the recirculation zone and then enters the gear chamber 20.

[0065] In one embodiment, the process involves forming a laminar flow stream through gear chamber 20. A “laminar flow stream,” as used herein, is a flow in which small disturbances in the form of eddies or vortices do not have sufficient energy to sustain; any eddies or vortices dissipate instantaneously; laminar flow as opposed to turbulent flow. The laminar flow stream includes a portion of FFS1 and a portion of F2 flowing through and around the Petition 870250079651, dated 05 / 09 / 2025, page 35 / 53 24 / 31 interlocking gears 22a and 22b, as shown by arrows M in Figures 1 and 2.

[0066] In one embodiment, the process also includes the formation of a vortex flow stream in the recirculation zone. A “vortex flow stream,” as used herein, is a flow stream in the recirculation zone where a portion of FFS1 and / or including a portion of F2 rotates around an axis to create a vortex. The recirculation zone (composed of FFS1 and F2) is located in the passage, such that the downstream end of the recirculation zone is bounded by the top of the gear teeth, the side wall of the passage is bounded by the other side, and the upstream end of the recirculation zone is defined by the location of the injectors, the injectors being at least 0.5 Ga upstream of inlet 19 (or at least one lw from inlet 19). The upstream end of the recirculation zone remains open to the viscous flow of FFS1 and FFS2, as shown by arrow 1 in Figure 1.The gear pump assembly 12 with two gears rotating in opposite directions to each other creates two recirculation zones, with a separate and discrete vortex flow in each recirculation zone, each recirculation zone being upstream of each respective gear 22a, 22b, as shown in Figure 1 and Figure 3B.

[0067] In one embodiment, the apparatus 10 includes a first injector 50a and a second injector 50b as shown in Figure 3A. Each injector includes a respective elongated conduit 52 with respective ports 54 for discharging the second fluid 36 as the respective first flow blade 60a and second flow blade 60b in FFS1 34. The first injector 50a is located at a distance from the second injector. The injectors 50 are located at least half a gear diameter, 0.5 Ga, upstream of inlet 19 (or are located at a distance 1 lwa upstream of inlet 19), thus defining a recirculation zone. The process includes introducing the Petition 870250079651, dated 05 / 09 / 2025, page 36 / 53 25 / 31 second fluid from each respective elongated conduit (face to face with ports 54) and form the respective first flow blade 60a and second flow blade 60b in FFS1 at a location at least 0.5 Ga (or at least one Iw) upstream of inlet 19. The process includes forming a first vortex flow 66a and a second vortex flow 66b in the respective first recirculation zone 70a and second recirculation zone 70b, as shown in Figure 1. The process includes feeding FFS1 34 and flow blades 60a, 60b into inlet 19; mixing, in gear chamber 20, the second fluid 36 with FFS1 34 to form a mixed flow stream 40 (mFF 40S); discharging mFFS 40 from outlet 42; and form an mFFS 40 having CoV from 0.1 to 0.5.

[0068] For evaluation purposes, Figures 4A to 4E show the apparatus 10 with injectors at different locations within passage 14 and gear pump assembly 12. In Figure 4A, location A indicates two injectors at a distance of 0.5 Ga upstream of inlet 19. Location C indicates a single injector within gear chamber 20 at a distance less than 0.5 Ga upstream of inlet 19. Location D indicates two injectors in gear chamber 20 in space 38 and a distance less than 0.5 Ga upstream of inlet 19. Location E indicates a single injector in passage 14 and a distance less than 0.5 Ga upstream of inlet 19.

[0069] Figure 4B shows a flow and mixing profile for two injectors at locations A in Figure 4A, with a cross-sectional view of mFFS 40 taken along line 4B-4B. Laminar flow Meo and vortex flow N form an mFFS with a CoV of 0.33. Figure 4B with the injectors at locations A is an example of the present disclosure.

[0070] Figure 4C shows a flow and mixing profile for a single injector at location C in Figure 4A, with a cross-sectional view of mFFS 40 taken along line 4C-4C. Laminar flow M and no vortex flow N form an mFFS with a CoV of 0.61. Figure 4C with Petition 870250079651, dated 05 / 09 / 2025, page 37 / 53 26 / 31 a single injector at site C is a comparative sample of the present disclosure.

[0071] Figure 4D shows a flow and mixing profile for two injectors at locations D in Figure 4A, with a cross-sectional view of mFFS 40 taken along line 4D-4D. Laminar flow M and no vortex flow N form an mFFS with a CoV of 0.54. Figure 4D with two injectors at locations D is a comparative sample of the present disclosure.

[0072] Figure 4E shows a flow and mixing profile for a single injector at location E in Figure 4A, with a cross-sectional view of mFFS 40 taken along line 4E-4E. The laminar flow Meo vortex flow N forms an mFFS with a CoV of 0.89. Figure 4E with a single injector at location E is a comparative sample of the present disclosure.

[0073] Figure 5 shows an embodiment of the apparatus 10 having a tapered section 15 in fluid communication with the passage 14 and located on an upstream side of the gear assembly 12. The tapered section 15 is in fluid communication with the gear chamber 20.

[0074] In one embodiment, the apparatus 10 includes the tapered section 15. The tapered section 15 is an annular body 28 with an upstream end 30 having a diameter that is greater than the length of the inlet width 21. The tapered section 15 has a downstream end 32 with a diameter that is the length of the inlet width 21. In other words, the diameter of the downstream end 32 is equal to or substantially equal to the inlet width 21.

[0075] Moving from the upstream end 30 to the downstream end 32, the tapered section 15 has a body 28 with a diameter that gradually reduces, or otherwise gradually diminishes, constricting the internal volume within the tapered section 15. In this way, the tapered section 15 has an upstream diameter that is greater than the width of the chamber which reduces until the downstream end having a diameter that is equal to, or Petition 870250079651, dated 05 / 09 / 2025, pages 38 / 53 27 / 31 substantially equal to, or less than, the width of the chamber. The constricted diameter of the tapered section 15 increases the pressure in the fluid flow stream when the fluid flow stream enters the gear chamber 20. In one embodiment, the process includes positioning the elongated conduits at the upstream end of the tapered section; introducing the second fluid from each respective elongated conduit into the FFS1 at a location at least one inlet width (Iw) upstream of the inlet; feeding the FFS1 and the second fluid to the inlet 19; mixing, in the gear chamber, the second fluid with the FFS1 to form a mixed fluid flow stream (mFFS); and discharging the mFFS from the outlet. In another embodiment, the process includes forming an mFFS with a CoV of 0.1 to 0.5.

[0076] This disclosure advantageously provides a process for mixing a second fluid (F2), as an additive to a molten polymer stream (FFS1) without the use of extruders and static mixers. In one embodiment, the present process is carried out using a liquid additive injection system that is placed in the conduit that carries the polymer stream to the gear pump. This disclosure also provides a specific gear profile to achieve effective mixing. The shear and mixing provided by the gear pump are capitalized to achieve the desired mixing.

[0077] By way of example, and not limitation, examples of modes of this disclosure are provided below. EXAMPLES

[0078] Table 1 below provides the materials used in the examples. Table 1 - Materials F2 (additive) FFS1 LDPE (2MI, 0.92 g / cm3) Density g / cm3 0.720 0.720 Viscosity [cP] 1.0 1,000,000 Temperature, °C 130 130 Petition 870250079651, dated 05 / 09 / 2025, page 39 / 53 28 / 31 Weight fraction 0.018 0.982

[0079] In one embodiment, an apparatus 100 is provided, as shown in Figure 1. Apparatus 100 is similar to apparatus 10 (disclosed above), except that apparatus 100 includes additional and / or alternative components to evaluate the mixing performance.

[0080] The elongated conduit 52 penetrates, or otherwise traverses, passage 14 and extends through the interior of passage 14. The elongated conduit 52 extends into the interior of the passage. A plurality of spaced ports extend along the length of one downstream side of the elongated conduit 52. The apparatus 100 may also include a source for F2, along with piping, valve(s), and pump(s) to supply F2 to the elongated conduit 52. For the apparatus 100, the distance between the axis of rotation 26a and the elongated conduit 52 is 7.6 inches (2.5 lw). The distance between the inlet and the injectors is 1.95 lw. For the apparatus 100, the outlet cylinder 16 is 18 inches (6.5 lw) long.

[0081] For evaluation purposes, an elongated conduit 152 is provided and includes two elongated conduits 156a, 156b spaced and parallel or substantially parallel to each other, as shown in Figures 6A-6B. Each elongated conduit 156a and 156b is a 0.5-inch Schedule 80 pipe with four 3 / 32-inch ports 156 spaced 1 inch apart. The ports 156 are on the downstream face of each elongated conduit 154a, 154b.

[0082] In configuration A, the elongated conduit 152 is oriented vertically in passage 14, so that the elongated conduit 154a and the elongated conduit 154b are parallel or substantially parallel to each axis of rotation 26a, 26b for the respective gears 22a, 22b, as shown in Figure 6A.

[0083] In configuration B, the elongated conduit 152 is oriented horizontally in passage 14, so that the elongated conduit 154a and the elongated conduit 154b are perpendicular or substantially perpendicular to each axis of rotation 26a, 26b for the gears, as Petition 870250079651, dated 05 / 09 / 2025, pages 40 / 53 29 / 31 shown in Figure 6B.

[0084] In apparatus 100, the pitch diameter for each gear is 2.756 inches. In gear chamber 20, both (i) the tooth backlash and (ii) the clearance between the gear tip and the housing are maintained at 0.01 inch. Gears with four different helix angles are provided for evaluation. Gears 122a, 122b have a helix angle of 0° (Figure 7A). Gears 222a, 222b have a helix angle of 7° (Figure 7B). Gears 322a, 322b have a helix angle of 30° (Figure 7C). Gears 422a, 422b have a double helix (herringbone) (Figure 7D).

[0085] Table 2 below provides the CoV values ​​for a cross-sectional plane of mFFS 40 in the outlet drum 16. Computational Fluid Dynamics (CFD), a modeling approach, is used to simulate the flow through the apparatus 100. CFD (Starccm+ V15) and mesh tool (SCORG) are used to generate the CoV values ​​in Table 2 below. The CoV values ​​are calculated using Equation 1, where the average additive concentration is estimated based on the additive inlet mass flow rate and the local additive concentration is estimated from the CFD results. The CoV values ​​are calculated through a cross-section (1.81 lwa downstream of the outlet) that is perpendicular to the flow stream. As mentioned earlier, CoV calculates the ratio of the standard deviation over the average concentration of the second fluid (F2).The standard deviation and average concentration values ​​are calculated based on the CFD simulation results under the aforementioned operating conditions. Simulations are run to achieve steady-state conditions when there are no further changes in the average and standard deviations of the concentration values ​​in different cross-sectional planes. Since the CFD simulation retains the details of velocity, pressure, temperature, and concentration values ​​in each computational cell, the values ​​of... Petition 870250079651, dated 05 / 09 / 2025, pages 41 / 53 30 / 31 standard deviation and average concentration in a given cross-section can be calculated. Table 2 - Mixture evaluation - CoV values________________________ Gear helix angle 0° Gear helix angle 7° Gear helix angle 30° Gear herringbone Configuration A (0°) Elongated conduit 0.33 0.5 0.7 0.1 Configuration B (90°) Elongated conduit 1.5 1.1 1.4 0.25

[0086] It was surprisingly found that the CoV values ​​indicative of the degree of mixing are lower for the 0° injection case (configuration A) compared to its 90° injection counterpart (configuration B), and this trend is consistent regardless of the gear design profile. Note that low CoV values ​​indicate better mixing, with a CoV value below 0.5 considered sufficient for most chemical processes (Paul, et al., Handbook of Industrial Mixing, 2003). In addition to the injection conduit orientation, the effect of the gear helix angle is also evident. The double helix (herringbone) gear showed the lowest CoV value, followed by the 0° helix angle (straight gear), with CoV values ​​increasing as the single helix angle increases.With increasing helix angle, the second fluid (additive) tends to accumulate on one side of the outlet conduit due to a pressure gradient promoted by the single helix gears. However, the additive flow becomes symmetrical for double helical (herringbone) gears due to the double helix angle (left and right) resulting in a zero liquid pressure gradient along the span, and also the symmetry provided by the gear teeth with different helix angles being equidistant from the gear's central plane makes their performance the best in mixing the additive.

[0087] Figure 9 shows the additive concentration profile for Petition 870250079651, dated 05 / 09 / 2025, pages 42 / 53 31 / 31 Straight, helical, and bi-helical (herringbone) gears for 0° and 90° injection. As described earlier, preferential flow is promoted by the helical gear where the additive accumulates on one side. However, for the bi-helical (herringbone) gear (Figure 8), the flow remains uniform with a continuous line of contact (elongation) resulting in uniform mixing. Thus, the CoV values ​​for the bi-helical (herringbone) gear are generally lower than those for straight and helical gears.

[0088] It has been found that increasing the helix angle promotes some preferential flow on the suction side of the gear pump. As the teeth disengage from each other, the discharge volume changes along the gear span. The gear profile with a large helix angle tends to open more on one side first, thus resulting in a low-pressure zone. Without adhering to a specific theory, this low-pressure zone pulls more additive from one side of the upstream C side of the gear chamber than the other, and thus creates a non-uniform distribution of the additive.

[0089] It is specifically intended that the present disclosure is not limited to the embodiments and illustrations contained herein, but includes modified forms of those embodiments, including portions of the embodiments and combinations of elements from different embodiments, as is the case within the scope of the following claims. Petition 870250079651, dated 05 / 09 / 2025, pp. 43 / 53

Claims

1 / 2 CLAIMS 1. Process, characterized in that it comprises: providing an apparatus comprising: (A) a passage with an interior for receiving a first flow stream (FFS1) comprising a molten polymeric composition, the passage having an inlet end and an opposite flow end;(B) a gear pump assembly comprising (i) a housing, (ii) a gear chamber in the housing, (iii) an inlet placing the flow end of the passage in fluid communication with the gear chamber, wherein the inlet having a width (Iw), (iv) a plurality of interlocking gears mounted for rotation in the gear chamber, wherein the gears have teeth that engage with each other in the chamber, and (v) an outlet in fluid communication with the gear chamber, (C) one or more injectors upstream of the gear pump assembly for adding a second fluid to the first flow stream, wherein the second fluid comprises an optional radically graftable species, an optional curing agent and a peroxide, wherein the peroxide has an activation temperature, wherein the injectors are located upstream of the inlet, wherein the process comprises introducing the second fluid from each injector into FFS1 at a location upstream of the inlet;Feed the FFS1 and the second fluid into the inlet; mix, in the gear chamber, the second fluid with the FFS1 to form a mixed fluid flow stream (mFFS); discharge the mFFS from the outlet into a die head to form a molded article; pass the molded article through a curing chamber; and crosslink, in the curing chamber, the polymer to form a crosslinked shaped article (CSA).

2. Process according to claim 1, characterized in that it comprises maintaining, during mixing and discharge, the temperature of the mFFS below the activation temperature of peroxide.

3. Process according to claim 1 or 2, characterized in that one or more injectors are located at a distance of at least half a gear diameter upstream from the inlet, the process comprising introducing the second fluid from each injector into the FFS1 at a location at least half a gear diameter upstream from the inlet.

4. Process according to any one of claims 1 to 3, characterized in that it comprises heating the mFFS above the activation temperature in the curing chamber.

5. Process according to any one of claims 1 to 4, characterized in that the second fluid comprises the peroxide and the radically graftable species, the process comprising grafting, in the curing chamber, the radically graftable species onto the polymer to form a grafted polymer; and crosslinking the grafted polymer to form a crosslinked grafted molded article (CgSA). Petition 870250079651, dated 05 / 09 / 2025, pp. 45 / 53

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