Method for producing graft polymers

Abstract

This disclosure provides a process. In one embodiment, the process includes providing an apparatus. The apparatus includes (A) a passage having an interior for receiving a first flowstream (FFS1) containing a molten polymer composition, the passage having an inlet end and an outlet end on the opposite side. The apparatus includes (B) (i) a housing, (ii) a gear chamber within the housing, and (iii) an inlet that fluidizes the outlet end of the passage to the gear chamber, with a width (I w The apparatus includes a gear pump assembly having an inlet having (iv) a plurality of meshing gears mounted to rotate within a gear chamber, the gears having teeth that engage with each other within the chamber, and (v) an outlet that is 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 to a first flow stream. The second fluid consists of radical-graftable species and peroxides. The peroxides have an activation temperature. The injectors are located upstream of the inlet. The process includes introducing the second fluid from each injector into the FFS1 at a location upstream of the inlet, and supplying the FFS1 and the second fluid into the inlet. The process includes mixing the second fluid with the FFS1 in the gear chamber to form a mixed fluid flow stream (mFFS), discharging the mFFS from the outlet into a curing chamber, and grafting radical-graftable species onto a polymer in the curing chamber to form a grafted polymer.

Description

[Technical Field]

[0001] Extruders and static mixers are commonly used to combine or otherwise mix two or more viscous materials, such as a polymer melt stream. Polymer melt streams are generally highly viscous, and the flow of the polymer melt stream in this process is typically laminar, without a spontaneous mixing mechanism. Due to the highly viscous nature of the polymer melt stream, the addition and mixing of small amounts of low-viscosity fluid products (additives) becomes problematic. While extruders (either twin-screw or single-screw) can be used to mix lower-viscosity liquid additives into the polymer melt stream, extruders are difficult to scale up, and production costs increase rapidly when increased production capacity and extruder size are desired.

[0002] Using static mixers has the disadvantage of increasing capital costs. Static mixers obstruct the flow, and consequently, create a risk of significant pressure drops in the polymer melting flow production process. The pressure drop resulting from the addition of static mixers to the flow process can create potential dead zones in the production flow stream. Dead zones can lead to long-term degradation of the polymer melting stream flow process.

[0003] In this technical field, there is a recognized need for alternative mixing processes for polymer melt streams that avoid extruders and / or static mixers. [Overview of the Initiative]

[0004] This disclosure provides a process. In one embodiment, the process includes providing an apparatus. The apparatus includes (A) a passage having an interior for receiving a first flowstream (FFS1) containing a molten polymer composition, the passage having an inlet end and an outlet end on the opposite side. The apparatus includes (B) (i) a housing, (ii) a gear chamber within the housing, and (iii) an inlet that fluidizes the outlet end of the passage to the gear chamber, with a width (I w The apparatus includes a gear pump assembly having an inlet, (iv) a plurality of meshing gears mounted to rotate within a gear chamber, each gear having teeth that engage with each other within the chamber, and (v) an outlet that is in fluid communication with the gear chamber. The apparatus includes (c) one or more injectors located upstream of the gear pump assembly for adding a second fluid to a first flow stream. The second fluid consists of radical-graftable species and peroxides. The peroxides have an activation temperature. The injectors are located upstream of the inlet. The process includes introducing the second fluid from each injector into the FFS1 at a location upstream of the inlet, and supplying the FFS1 and the second fluid into the inlet. The process includes mixing the second fluid with the FFS1 in the gear chamber to form a mixed fluid flow stream (mFFS), discharging the mFFS from the outlet into a curing chamber, and grafting radical-graftable species onto a polymer in the curing chamber to form a grafted polymer. [Brief explanation of the drawing]

[0005] [Figure 1] This is a cross-sectional view of a device equipped with a gear pump according to one embodiment of the present disclosure. [Figure 2] This is an enlarged view of region 2 in Figure 1. [Figure 3A] Figure 1 is an exploded perspective view of the apparatus, showing a fluid sheet according to one embodiment of the present disclosure. [Figure 3B] This is a cross-sectional view of region 3B in Figure 3A. [Figure 4A] Figure 1 is a cross-sectional view of the apparatus, showing alternative locations for the injector within the apparatus's passage. [Figure 4B] A cross-sectional view of an apparatus showing the flow and mixing profiles corresponding to the injector position in FIG. 4A. For each respective flow and mixing profile, a cross-sectional view of the resulting mixed fluid flow stream and the corresponding CoV value is also shown. [Figure 4C] A cross-sectional view of an apparatus showing the flow and mixing profiles corresponding to the injector position in FIG. 4A. For each respective flow and mixing profile, a cross-sectional view of the resulting mixed fluid flow stream and the corresponding CoV value is also shown. [Figure 4D] A cross-sectional view of an apparatus showing the flow and mixing profiles corresponding to the injector position in FIG. 4A. For each respective flow and mixing profile, a cross-sectional view of the resulting mixed fluid flow stream and the corresponding CoV value is also shown. [Figure 4E] A cross-sectional view of an apparatus showing the flow and mixing profiles corresponding to the injector position in FIG. 4A. For each respective flow and mixing profile, a cross-sectional view of the resulting mixed fluid flow stream and the corresponding CoV value is also shown. [Figure 5] A side view of an apparatus with a tapered portion according to an embodiment of the present disclosure. [Figure 6A] A front view of a vertically oriented injection conduit according to an embodiment of the present disclosure. [Figure 6B] A front view of a horizontally oriented injection conduit according to an embodiment of the present disclosure. [Figure 7A] A perspective view of meshing gears, each according to a respective embodiment of the present disclosure. [Figure 7B] A perspective view of meshing gears, each according to a respective embodiment of the present disclosure. [Figure 7C] A perspective view of meshing gears, each according to a respective embodiment of the present disclosure. [Figure 8] A perspective view of a herringbone gear. [Figure 9](A) Additive concentration profiles for spur gear (0° twist), helical gear (7° twist), helical gear (30° twist), and herringbone gear at injection angles of 0° and 90°. [Modes for carrying out the invention]

[0006] definition All references to the periodic table refer to the version published by CRC Press, Inc., 1990–1991. References to element groups in this table refer to a new notation used to number the groups.

[0007] For the purposes of U.S. patent practice, the content of any referenced patent, patent application, or publication, in particular with respect to the disclosure of definitions (to the extent that it does not conflict with any definitions specifically provided in this disclosure), is incorporated by reference in its entirety (or its corresponding U.S. version is incorporated by reference in this way).

[0008] Numerical ranges disclosed herein include all values ​​from the lower limit to the upper limit (including the lower and upper limits). In the case of ranges that include explicit values ​​(e.g., 1 or 2, or 3 to 5, or 6, or 7), any subrange between any two explicit values ​​is included (for example, the above range of 1 to 7 includes subranges such as 1 to 2, 2 to 6, 5 to 7, 3 to 7, 5 to 6, etc.).

[0009] Unless otherwise stated, implied by 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.

[0010] Where used, the terms “blend” or “polymer blend” refer to a mixture of two or more polymers. A blend may or may not be miscible (not phase-separated at the molecular level). A blend may or may not be phase-separated. A blend may or may not contain one or more domain configurations as determined by transmission electron spectroscopy, light scattering, X-ray scattering, and other methods known in the art. A blend may be influenced by the physical mixing of two or more polymers at a macro level (e.g., melt blending or formulation of resins) or at a micro level (e.g., simultaneous formation in the same reactor).

[0011] The term "composition" refers to a mixture of materials that constitute a composition, as well as reaction products and decomposition products formed from the materials of the composition.

[0012] The terms “comprising,” “including,” and “having,” and their derivatives, are not intended to exclude the presence of any additional components, processes, or procedures, whether or not they are specifically disclosed. To avoid any doubt, all compositions claimed through the use of the term “comprising” may, unless otherwise stated, include any additional additives, adjuvants, or compounds, whether or not they are polymers. In contrast, the term “consisting essentially of” excludes any other components, processes, or procedures from the scope of any prior description, except those not essential for operability. The term “consisting of” excludes any components, processes, or procedures that are not specifically described or enumerated. The term “or” refers to the enumerated members individually and in any combination, unless otherwise stated.

[0013] Ethylene polymers (commonly referred to as polyethylene) are polymers containing units derived from a majority (more than 50 mol%) of ethylene monomers. These include polyethylene homopolymers or copolymers (meaning units derived from two or more comonomers). Common forms of polyethylene known in the art include low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), ultra-low-density polyethylene (ULDPE), single-site catalyst linear low-density polyethylene (m-LLDPE) which includes both linear low-density resins and substantially linear low-density resins, ethylene plastomers (POP) and ethylene elastomers (POE), medium-density polyethylene (MDPE), and high-density polyethylene (HDPE). These polyethylene materials are generally known in the art. However, the following description may help understand the differences between some of these different polyethylene resins.

[0014] The term "LDPE" may also be referred to as "high-pressure ethylene polymer" or "highly branched polyethylene," but is defined to mean that the polymer is partially or completely homopolymerized or copolymerized in an autoclave or tubular reactor at a pressure exceeding 14,500 psi (100 MPa) using a free radical initiator such as a peroxide (see, for example, U.S. Patent No. 4,599,392, incorporated herein by reference). LDPE resins typically have a viscosity of 0.916–0.935 g / cm³. 3 It has a density within the range.

[0015] The term "LLDPE" includes both resins produced using traditional Ziegler-Natta catalyst systems and chromium-based catalyst systems, as well as single-site catalysts including but not limited to mono- or bis-cyclopentadienyl catalysts (typically referred to as metallocenes), geometrically constrained catalysts, pyridylamine catalysts, phosphineimine catalysts, and polyvalent aryloxyether catalysts (typically referred to as bisphenylphenoxy), and includes linear, substantially linear, or heterogeneous polyethylene copolymers or homopolymers. LLDPE contains fewer long-chain branches than LDPE and includes substantially linear ethylene polymers as further defined in U.S. Patents 5,272,236, 5,278,272, 5,582,923 and 5,733,155; homogeneously branched linear ethylene polymer compositions such as those in U.S. Patent 3,645,992; heterogeneously branched ethylene polymers such as those prepared according to the process disclosed in U.S. Patent 4,076,698; and / or blends thereof (such as those disclosed in U.S. Patents 3,914,342 or 5,854,045). LLDPE 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.

[0016] The term "MDPE" refers to 0.926-0.935 g / cm³ 3 This refers to polyethylene having a density of . "MDPE" is typically produced using chromium or Ziegler-Natta catalysts, or single-site catalysts including but not limited to substituted mono- or bis-cyclopentadienyl catalysts (typically referred to as metallocenes), geometrically constrained catalysts, pyridylamine catalysts, phosphineimine catalysts, and polyvalent aryloxyether catalysts (typically referred to as bisphenylphenoxy), and typically has a molecular weight distribution ("MWD") greater than 2.5.

[0017] The term "HDPE" generally refers to a single-site catalyst prepared using a catalyst including, but not limited to, Ziegler-Natta catalysts, chromium catalysts, or substituted mono- or bis-cyclopentadienyl catalysts (typically referred to as metallocenes), geometrically constrained catalysts, pyridylamine catalysts, phosphineimine catalysts, and polyvalent aryloxy ether catalysts (typically referred to as bisphenylphenoxy), at a concentration of approximately 0.935 g / cm³. 3 Super ~ maximum approx. 0.980g / cm 3 This refers to polyethylene having a certain density.

[0018] The term "ULDPE" generally refers to single-site catalysts, including but not limited to Ziegler-Natta catalysts, chromium catalysts, or substituted mono- or bis-cyclopentadienyl catalysts (typically referred to as metallocenes), geometrically constrained catalysts, pyridylamine catalysts, phosphineimine catalysts, and polyvalent aryloxyether catalysts (typically referred to as bisphenylphenoxy), prepared using 0.855–0.912 g / cm³ 3 This refers to polyethylene having a density of 0.855 to 0.912 g / cm³. Examples of ULDPE include, but are not limited to, polyethylene (ethylene-based) plastomers and polyethylene (ethylene-based) elastomers. Polyethylene (ethylene-based) elastomer plastomers generally have a density of 0.855 to 0.912 g / cm³. 3 It has a density of .

[0019] "Olefins" are unsaturated aliphatic hydrocarbons that have a carbon-carbon double bond.

[0020] An "olefin polymer" (commonly referred to as "polyolefin") is a polymer that contains a majority by weight percent of polymerizable olefin monomers (based on the total amount of polymerizable monomers) and may optionally contain at least one comonomer. Non-limiting examples of olefin polymers include ethylene polymers and propylene polymers.

[0021] As used herein, the terms “polymer” or “polymer material” refer to compounds prepared by polymerizing monomers, whether of the same or different types, providing multiple and / or repeating “units” or “mer units” constituting the polymer in a polymeric form. Thus, the general term polymer encompasses the term homopolymer, which is commonly used to refer to polymers prepared from only one type of monomer, and the term copolymer, which is commonly used to refer to polymers prepared from at least two types of monomers. It also encompasses all forms of copolymers, such as random and block copolymers. The terms “ethylene / α-olefin polymer” and “propylene / α-olefin polymer” refer to the aforementioned copolymers and one or more additional polymerizable α-olefin monomers prepared by polymerizing ethylene or propylene, respectively. Polymers are often referred to as "made of" one or more specified monomers, "based on" a specified monomer or type of monomer, or "containing" a specified monomer content. However, it should be noted that in this context, the term "monomer" is understood to refer to the specified monomer of the polymerization residue, and not to the non-polymerized species. In general, polymers as used herein are referred to in terms of "units," which are the polymerization forms of the corresponding monomers.

[0022] A "propylene polymer" (interchangeably referred to as "polypropylene") is a polymer containing more than 50 mole percent of polymerizable propylene monomer (based on the total amount of polymerizable monomers) and optionally containing at least one comonomer. Propylene polymers include propylene homopolymers and propylene copolymers (meaning units derived from propylene and one or more comonomers). The terms "propylene polymer" and "polypropylene" may be used interchangeably. A non-limiting example of a propylene polymer (polypropylene) is at least one C2 or C4-C 10It is a propylene / α-olefin copolymer having an α-olefin comonomer.

[0023] Test method Degree of mixing. The degree of mixing is quantified by the coefficient of variance (CoV) of the local concentration of a second fluid (F2) with respect to a first flow stream (FFS1) on a specific cross-sectional plane. The CoV defined by Equation 1 is calculated on a cross-sectional plane perpendicular to the average flow velocity, where C is the concentration at position r and time t,

[0024]

Number

[0025]

Number

[0026] Density is measured in accordance with ASTM D792, Method B. Results are recorded in grams per cubic centimeter (g) (g / cc or g / cm 3 )). The density of the fluid flow stream (Table 1) is measured in accordance with ASTM D792. Results are recorded in grams per cubic centimeter (g) (g / cc or g / cm 3 ).

[0027] The melt index (I2 or MI) is measured in accordance with ASTM D - 1238 at 2.16 kg and 190 °C. Values are reported in g / 10 min corresponding to grams eluted per 10 minutes.

[0028] Viscosity refers to the resistance of a fluid deformed by either shear stress or tensile stress. For the purposes of this specification, viscosity is measured at 130°C using a Brookfield viscometer measured in accordance with ASTM D445. The results are reported in centipoise (cP).

[0029] Detailed explanation This disclosure provides a process. In one embodiment, the process includes providing an apparatus. The apparatus includes (A) a passage having an interior for receiving a first flowstream (FFS1). FFS1 is a molten polymer composition. The passage has an inlet end and an outlet end on the opposite side. The apparatus includes (B) a gear pump assembly. The gear pump assembly includes (i) a housing, (ii) a gear chamber within the housing, and (iii) an inlet that fluidizes the outlet end of the passage to the gear chamber. The inlet has a width (I w The gear pump assembly also includes (iv) a plurality of meshing gears mounted to rotate within a gear chamber. The gears have teeth that engage with each other within the chamber. The gear pump assembly also includes (v) an outlet that is in fluid communication with the gear chamber. The apparatus further includes (C) one or more injectors upstream of the gear pump assembly for adding a second fluid to the first flow stream. The second fluid includes (i) radical-graftable species and (ii) peroxides. The peroxides have an activation temperature. The process includes introducing the second fluid from each injector into the FFS1 at a position upstream of the inlet, supplying the FFS1 and the second fluid into the inlet, and mixing the second fluid with the FFS1 in the gear chamber to form a mixed fluid flow stream (mFFS). The process further includes discharging the mFFS from the outlet into a curing chamber, and grafting the radical-graftable species onto a polymer in the curing chamber to form a grafted polymer.

[0030] This process includes providing an apparatus. The apparatus includes (A) a passage having an interior for receiving a first flowstream (FFS1). The passage has an opening at the inlet end and an opening at the opposite outlet end. The apparatus includes (B) a gear pump assembly. The gear pump assembly includes (i) a housing, (ii) a gear chamber within the housing, and (iii) an inlet for fluid communication between the passage and the gear chamber, with a width (I w The apparatus includes an inlet having (iv) a plurality of meshing gears mounted to rotate within a gear chamber, each gear having teeth that engage with each other within the chamber, and (v) an outlet that is in fluid communication with the gear chamber. The apparatus includes (c) one or more injectors located upstream of the gear pump assembly for adding a second fluid to the first flowstream. In one embodiment, each injector is located upstream of the inlet at a distance of at least half the diameter of the gear. In one embodiment, each injector has an elongated conduit extending into the passage. In one embodiment, the process includes introducing the second fluid into the FFS1 from each elongated conduit at a position located upstream of the inlet at least half the diameter of the gear. The process includes supplying the FFS1 and the second fluid into the inlet, mixing the second fluid with the FFS1 within the gear chamber to form a mixed fluid flowstream (mFFS), and discharging the mFFS from the outlet.

[0031] This specification describes the features and operation of embodiments of the present disclosure, with particular reference to the accompanying drawings, which are not intended to limit the scope. In the drawings, the same numbers are used throughout to indicate similar elements of the apparatus (unless otherwise indicated).

[0032] Figures 1 and 2 show a mixing apparatus 10 having a gear pump 12, a passage 14, and an outlet barrel 16. The passage 14 is an annular body having a substantially uniform diameter along its length, or a uniform diameter. The passage 14 may or may not include a tapered section 15, as disclosed below. If there is no tapered section, the passage 14 has a substantially uniform diameter along its length, or a uniform diameter.

[0033] The 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 confining a certain volume using meshing gears within a housing, the meshing gears mechanically transporting the fluid using a circulating pump action. The rotating gears form a fluid seal with the pump housing and generate an attractive force at the pump inlet. The fluid drawn into the pump is confined within the cavity of the rotating gears, and the fluid is then transported to the outlet.

[0034] Figure 1 is a cross-sectional view of the apparatus 10. Figure 1 shows a 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 allows a passage 14 to fluidly communicate 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 extending between the opposite sides of the housing 18. If the vertical length of the inlet 19 is not the same as the horizontal length of the inlet 19, the inlet width 21 is the larger of the vertical length or the horizontal length. If 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 the inlet 19 can vary, the length of the inlet width 21 can vary accordingly. In other words, the inlet width 21 may or may not include the total diameter of the meshing gears 22a and 22b, in addition to the small clearance or gap between each gear and the inner wall of the gear chamber 20. The length or extent of the inlet width 21 is interchangeable with "I w It is referred to as "".

[0035] Within the gear chamber 20 are several (or two) meshing gears (replaced by gear(multiple) or gear(singular)), gear 22a and gear 22b. Each gear 22a, 22b has teeth 24. The teeth 24 of gear 22a mesh with (or connect with) the teeth 24 of gear 22b. In one embodiment, gear 22a is the same size and shape as gear 22b, and as a result, gears 22a and 22b each have a gear diameter 25 of the same length. As used herein, “gear diameter” (also known as “outer gear diameter”) is the length of a straight segment that starts from one gear tooth, passes through the axis of rotation, crosses the gear, and extends to the opposite gear tooth, defining the outermost gear diameter, as indicated by the gear diameter 25, and the gear diameter 25 is the straight segment shown in Figure 1. The gear diameter 25 is interchangeably referred to as “G d The term "gear diameter" is interchangeably referred to as "gear outer diameter" and / or "pitch diameter". Alternatively, gear 22a may have a different size and / or shape from gear 22b. Each gear 22a, 22b is supported by a separate shaft (not shown). Generally, one gear is driven by a motor, which drives the other gear (idler). In one embodiment, both shafts may be driven by motors. The shafts are supported by bearings on each side of the casing. Each shaft rotates its respective gear around a rotation axis. Gear 22a rotates around rotation axis 26a, and gear 22b rotates around rotation axis 26b. As each gear 22a, 22b rotates around its respective rotation axis, the teeth 24 are mated, meshed, engaged, or otherwise engaged with each other. As the rotation of the gears continues, the teeth disengage from each other.

[0036] In one embodiment, each gear has a helix angle. As used herein, “helix angle” is the angle between the axis of rotation of the gear and the line tangent to one of the teeth, as viewed from the front view of the gear. The helix angle can be between 0° and 45°. In a further embodiment, the helix angles of gears 22a and 22b are between 0° and 5°.

[0037] In one embodiment, each gear is a herringbone gear. A "herringbone gear" is a gear in which the gear teeth have a helix angle α from one end of the gear cylinder to the center of the gear cylinder and an angle of 360-α from the center of the gear cylinder to the other end of the gear cylinder. The angle is measured from the edge of the teeth of the helical gear to the axis of the gear cylinder, which moves clockwise. This creates a "V-shaped pattern" (shown in Figure 8) on the gear teeth on the gear cylinder, hence the name "herringbone."

[0038] This process involves supplying a first fluid flow stream 34 (shaded gray area in Figure 1) into a passage 14. The passage 14 has an upstream or inlet end for receiving the first fluid flow stream. The passage 14 has a downstream end, i.e., an outlet end, which is in fluid communication with an inlet 19. As used herein, “fluid flow stream” means a material that is in a fluid state and moves as a stream or otherwise flows. Fluid flow differs from the flow of fine solid particles (e.g., sand injection) 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, from the use of a pump. Non-limiting examples of the first fluid flow stream (compatiblely referred to as “FFS1”) material include polymers in a molten, dissolved, or otherwise flowable 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 to 1000 g / 10 min, or 0.1 g / 10 min to 100 g / 10 min, or 0.1 g / 10 min to 10 g / 10 min.

[0039] The apparatus 10 includes one or more injectors 50 for introducing a second fluid into the FFS1. The apparatus 10 may include one, two, three, four, five, 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 supply source for the second fluid, along with piping, valves, and pumps for supplying 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, and (ii) a radical graftable species. In one embodiment, the second fluid has a viscosity lower than that of the FFS1. F2 is a fluid, and may or may not contain solid particles dispersed therein, and it is understood that F2 has a viscosity lower than that of the FFS1. 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.

[0040] Non-limiting examples of suitable free radical initiators include organic initiators such as dicumyl peroxide, di-tert-butyl peroxide, t-butylbenzoyl peroxide, benzoyl peroxide, cumene hydroperoxide, t-butyl peroctoate, methyl ethyl ketone peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, lauryl peroxide, and tert-butyl peracetate, as well as combinations thereof. Free radical initiators (peroxides) have an activation temperature.

[0041] Various radical-graftable species may be bonded to the FFS1 polymer composition individually or as relatively short grafts. Each of these radical-graftable species comprises an unsaturated molecule containing at least one heteroatom. Examples of radical-graftable species include, but are not limited to, silane comonomers, maleic anhydride, dibutyl maleate, dicyclohexyl maleate, diisobutyl maleate, dioctadecyl maleate, N-phenylmaleimide, citraconic anhydride, tetrahydrophthalic anhydride, bromomaleic anhydride, chloromaleic anhydride, nadic anhydride, methylnadic anhydride, alkenyl succinic anhydride, maleic acid, fumaric acid, diethyl fumarate, itaconic acid, citraconic acid, crotonic acid, and their respective esters, imides, salts, and Diels-Alder adducts.

[0042] Radical-graftable species may be silane comonomers. Silane comonomers having the following formula can be grafted onto the FFS1 polymer composition,

[0043] [ka] In the formula, R 1 x is a hydrogen atom or a methyl group, x is 0 or 1, provided that if x is 1, n is at least 1, m and n are independently integers from 0 to 12 (including the ends) or from 1 to 4, and each R 2These are independently hydrolyzable organic groups, such as alkoxy groups having 1 to 12 carbon atoms (e.g., methoxy, ethoxy, butoxy), aryloxy groups (e.g., phenoxy), araloxy groups (e.g., benzyloxy), aliphatic acyloxy groups having 1 to 12 carbon atoms (e.g., formyloxy, acetyloxy, propanoyloxy), amino groups or substituted amino groups (e.g., alkylamino, arylamino), or lower alkyl groups having 1 to 6 carbon atoms (including both ends), provided that one or less of the three R groups are alkyl. These silanes may be grafted into the FFS1 polymer composition by using a suitable amount of organic peroxide.

[0044] Non-limiting examples of suitable silanes include ethylenically unsaturated hydrocarbyl groups such as vinyl, allyl, isopropenyl, butenyl, cyclohexenyl, or gamma-(meth)acrylooxyallyl groups, and unsaturated silanes containing hydrolyzable groups such as hydrocarbyloxy, hydrocarbonyloxy, or hydrocarbylamino groups. Non-limiting examples of hydrolyzable groups include methoxy, ethoxy, formyloxy, acetoxy, propionyloxy, and alkyl or arylamino groups. In one embodiment, the silane comonomer is selected from vinyl trimethoxysilane (VTMS), vinyl triethoxysilane, vinyl triacetoxysilane, gamma-(meth)acrylooxypropyltrimethoxysilane, and combinations thereof.

[0045] In one embodiment, each injector 50 includes an elongated conduit 52 that extends into, penetrates, or otherwise traverses the interior of the passage 14. Each elongated conduit 52 traverses part of or the entire diameter of the passage 14, and each elongated conduit 52 extends across the interior of the passage 14.

[0046] In one embodiment, each elongated conduit 52 includes a plurality of spaced-out portion ports 54 extending along the downstream length of each elongated conduit 52. The ports 54 discharge or otherwise distribute the second fluid along the length of each elongated conduit 52. In one embodiment, the ports 54 discharge a continuous flow of the second fluid along the length of each conduit forming a fluid sheet. As used herein, “fluid sheet” means a substantially continuous or continuous fluid body composed of the second fluid arranged within the FFS 1, the body of the fluid sheet having length, width, and height when the FFS 1 is viewed from a cross-sectional view downstream of the elongated conduits. Figure 3A is an exploded perspective view of the apparatus 10 with the passage 14 and housing 18 removed, and Figure 3A shows the fluid sheets 60a, 60b formed from the respective injectors 50a, 50b (each having its respective elongated conduit 52 and spaced-out ports 54). Figure 3A shows fluid sheets 60a and 60b, each having a body 62, each body 62 having a continuous volume of F2, and each body 62 having dimensions of length (L), width (W), and height (H).

[0047] Returning to Figure 1, in one embodiment, the injector 50 is positioned at a distance of at least half the gear diameter (i.e., 0.5G). d ) is located upstream of the inlet 19. For example, if gear 22a (and / or gear 22b) has a diameter of 32 cm, then the distance is half the gear diameter (i.e., 0.5 G). d The distance is 16 cm. This process involves introducing the second fluid 36 (referred to interchangeably as "F2") into the FFS1 34 over a distance of at least half the gear diameter (i.e., 0.5 G). d ) Only upstream from entrance 19, or 1G d ~5G d , or 1G d ~3G d , or 1.5G d ~3G dThis includes introducing the inlet 19 upstream by a distance of . In one embodiment, the apparatus 10 includes two injectors, a first injector 50a and a second injector 50b, wherein injector 50a is spaced apart from injection 50b along a passage diameter 56, and each injector 50a, 50b (and passage diameter 56) is at least 0.5G as shown in Figure 1. d It is located upstream from entrance 19 by a certain distance.

[0048] In one embodiment, the length of the inlet width 21 is greater than the length of the gear diameter 25. The injector 50 has at least an inlet width (I w It is located upstream of the inlet 19 by a distance of ) . This process introduces the second fluid 36 (referred to interchangeably as "F2") into the FFS1 34, at least 1 I w From entrance 19 upstream for a distance of that length, or 1 I w ~5 I w , or 1 I w ~3 I w , or 1.5 I w ~3 I w This includes introducing the inlet 19 upstream by a certain distance. In one embodiment, the apparatus 10 includes two injectors, a first injector 50a and a second injector 50b, where injector 50a is spaced apart from injection 50b along a passage diameter 56, and each injector 50a, 50b (and passage diameter 56) is as shown in Figure 1. w It is located upstream from entrance 19 by a certain distance.

[0049] In one embodiment, each injector includes a set of multiple spaced-apart portion ports extending along a portion of the passage sidewall ("wall injector"). The ports are formed through the sidewall and are in fluid communication with a second fluid source, as disclosed in jointly filed U.S. Patent Application No. _____________ Filing Date _____________ (84964-US-PSP). The entire contents of that application are incorporated herein by reference. The wall injector is at least half the gear diameter (i.e., 0.5G) dEven if it is located upstream of the inlet 19 by the distance of ), as disclosed above with respect to the injector 50, at least the inlet width I w It may also be located a certain distance upstream from entrance 19.

[0050] This process includes supplying FFS1 and F2 into the inlet 19 and mixing F2 36 with FFS1 34 in the gear chamber 20. FFS1 34 and F2 36 enter the gear chamber 20 from the passage 14. The reverse-rotating gears 22a and 22b generate an attractive force in region 4 that traps or otherwise pulls FFS1 and F2 into the gear chamber 20. As the reverse rotation of gears 22a and 22b continues, FFS1 and F2 stretch in the space 38 between the teeth 24 and the inner wall of the gear chamber 20, as indicated by arrow M in Figure 1. Further rotation of the gears continues the stretching, generating a compressive force in the space 38 and mixing F2 with FFS1. When the teeth 24 from gear 22a engage (or re-engage) with the teeth 24 from gear 22b in region 5, the captured FFS2 mixed within FFS1 is discharged from the gear chamber 20 and exits through outlet 42 as a mixed fluid flowstream 40 (i.e., "mFFS40"). This "suction-extension-compression-discharge" cycle is repeated as gears 22a and 22b continue to rotate in opposite directions, with the suction force capturing new amounts of FFS1 34 and F2 36 between the meshing teeth and the inner wall of the gear chamber, and the cycle continues.

[0051] This process includes discharging the mFFS 40 from outlet 42. The mFFS 42 flows into the curing chamber 16 from outlet 42, as shown in Figure 5. A non-limiting example of a suitable curing chamber is a high-temperature tube ("high-temperature tube" is a tube or chamber that can be heated above the peroxide activation temperature). This process includes grafting radical-graftable species onto the polymer within the curing chamber 16 to form a grafted polymer.

[0052] This process involves heating mFFS40 in a curing chamber to a temperature above the peroxide activation temperature. Exposure to a temperature above the peroxide activation temperature induces the grafting of radical-graftable species onto the polymer.

[0053] While not bound by any particular theory, the incorporation of functional monomers into polymers is thought to be achieved by radical-mediated grafting in the molten state of the polymer. Under this process, peroxides decompose into alkoxy radicals (above the peroxide activation temperature), abstracting hydrogen from the polymer and yielding polymer central radicals. These radicals then proceed to add to the unsaturated monomer. Through a series of addition and growth steps, a functionalized (grafted) material is obtained.

[0054] In one embodiment, the process includes maintaining the temperature of the mFFS below the peroxide activation temperature during mixing and discharge to prevent the peroxide from decomposing before complete homogenization.

[0055] Alternatively, the desired temperature for peroxide decomposition can be achieved through shear heating in the gear pump. Additional heat can also be supplied externally to obtain the desired activation temperature of the peroxide. Once temperature and homogeneity are achieved, the residence time required for the optimal grafting level is minimal. The desired residence time can be achieved by introducing the mFFS into a heated zone (e.g., a heated pipe) after the mFFS has been discharged from the gear pump.

[0056] In one embodiment, the minimum residence time is 4 half-lives at the peroxide activation temperature (peroxide decomposition temperature).

[0057] While not bound by any particular theory, the applicant places the second fluid within the FFS1 at a distance that is at least half the gear diameter (i.e., at least one I wIt was found that introducing the fluid a distance upstream of the inlet 19 unexpectedly creates or otherwise defines a recirculation zone within the passage 14 (or alternatively, within the tapered section). As used herein, “recirculation zone” means the downstream end defined by the plane encompassing the inlet 19 and the area from the inlet 19 by at least half the gear diameter (0.5G). d ) away from and located upstream (i.e., at least 1 I from entrance 19) w This is a volumetric portion (or volumetric portion within the tapered section) within passage 14, having an upstream end defined by a plane encompassing an elongated conduit (located separately upstream). The rotation of gears 22a and 22b generates (i) laminar flow streams of FFS1 and the second fluid, and (ii) eddy flow streams of FFS1 and the second fluid within the volumetric portion. The recirculation zone performs two actions: (1) the recirculation zone moves the incoming second fluid sheet (F2) to the low-pressure zone at the apex of the gear meshing zone, and (2) the recirculation zone enhances the mixing of the second fluid sheet (F2) so that a portion of the second fluid F2 is first mixed within the recirculation zone and then enters the gear chamber 20.

[0058] In one embodiment, this process includes forming a laminar flow stream through the gear chamber 20. As used herein, “laminar flow stream” means a flow in which small turbulence in the form of vortices or eddies does not have enough energy to sustain its state, where vortices or eddies dissipate instantaneously, and laminar flow is not suitable for turbulent flow. The laminar flow stream includes portions of FFS1 and F2 flowing through and around the meshing gears 22a and 22b, as indicated by arrow M in Figures 1 and 2.

[0059] In one embodiment, the process also includes forming a vortex flow stream within a recirculation zone. As used herein, “vortex flow stream” is a flow stream within a recirculation zone that includes a portion of FFS1 and / or a portion of F2, which rotates around an axis to generate a vortex. The recirculation zone (consisting of FFS1 and F2) is defined such that the downstream end of the recirculation zone is in contact with the top of a gear tooth, the passage sidewall is in contact with another side, the upstream end of the recirculation zone is defined by the position of the injector, and the injector is at least 0.5G d It is located at a distance upstream from entrance 19 (i.e., at least 1 I from entrance 19). w It is located within the passage (at a distance from each other). The upstream end of the recirculation zone remains open to the viscous flows of FFS1 and FFS2, as indicated by arrow 1 in Figure 1. The gear pump assembly 12, having two gears rotating in opposite directions to each other, generates two recirculation zones, each containing a separate discrete vortex flow, and each recirculation zone is located upstream of its respective gears 22a and 22b, as shown in Figures 1 and 3B.

[0060] In one embodiment, the apparatus 10 includes a first injector 50a and a second injector 50b, as shown in Figure 3A. Each injector includes an elongated conduit 52 having a port 54 for discharging the second fluid 36 into the FFS1 34 as a first flow sheet 60a and a second flow sheet 60b, respectively. The first injector 50a is separated from the second injector by a certain distance. The injector 50 has a diameter of at least half the gear diameter, 0.5G d Only the entrance 19 is located upstream (i.e., 1 I w The recirculation zone is defined by the distance (located upstream from inlet 19) thereafter. This process involves introducing the second fluid from each elongated conduit (towards port 54) and introducing each of the first flowsheet 60a and second flowsheet 60b into the FFS1 at least 0.5G d (that is, at least 1 I wThis process includes forming a first eddy flow 66a and a second eddy flow 66b in the first recirculation zone 70a and the second recirculation zone 70b, respectively, as shown in Figure 1. This process includes supplying the FFS1 34 and flow sheets 60a and 60b into the inlet 19, mixing a second fluid 36 with the FFS1 34 in the gear chamber 20 to form a mixed fluid flow stream 40 (mFF 40S), discharging the mFFS 40 from the outlet 42, and forming the mFFS 40 having a CoV of 0.1 to 0.5.

[0061] For evaluation purposes, Figures 4A to 4E show the device 10 with injectors at different positions within the passage 14, and the gear pump assembly 12. In Figure 4A, position A is 0.5G. d This indicates the two injectors located upstream of inlet 19 at a distance of 0.5G. Position C is 0.5G. d The single injector in the gear chamber 20 is located less than a distance upstream of the inlet 19. Position D is in space 38 and is 0.5G. d The two injectors in the gear chamber 20 are located less than a distance upstream from the inlet 19. Position E is in passage 14 and is at 0.5G. d This indicates a single injector located less than a certain distance upstream of inlet 19.

[0062] Figure 4B shows the flow and mixing profiles of the two injectors at position A in Figure 4A, and a cross-sectional view of the mFFS 40 is taken along line 4B-4B. The laminar flow M and eddy flow N form an mFFS with a CoV of 0.33. Figure 4B, with the injectors at position A, is an example of the present disclosure.

[0063] Figure 4C shows the flow and mixing profiles of a single injector at position C in Figure 4A, and a cross-section of the mFFS 40 is taken along line 4C-4C. The laminar flow M and non-edgy flow N form an mFFS with a CoV of 0.61. Figure 4C, with a single injector at position C, is a comparative sample of the present disclosure.

[0064] Figure 4D shows the flow and mixing profiles of the two injectors at position D in Figure 4A, and a cross-sectional view of the mFFS 40 is taken along line 4D-4D. The laminar flow M and non-eddy flow N form an mFFS with a CoV of 0.54. Figure 4D, with the two injectors at position D, is a comparative sample of the present disclosure.

[0065] Figure 4E shows the flow and mixing profiles of a single injector at position E in Figure 4A, and a cross-sectional view of the mFFS 40 is taken along line 4E-4E. The laminar flow M and eddy flow N form an mFFS with a CoV of 0.89. Figure 4E, with a single injector at position E, is a comparative sample of the present disclosure.

[0066] Figure 5 shows an embodiment of the device 10 having a tapered section 15 that is in fluid communication with the passage 14 and located upstream of the gear assembly 12. The tapered section 15 is in fluid communication with the gear chamber 20.

[0067] In one embodiment, the device 10 includes a tapered section 15. The tapered section 15 is an annular body 28 having an upstream end 30 whose diameter is greater than the length of the inlet width 21. The tapered section 15 has a downstream end 32 whose diameter is the length of the inlet width 21. In other words, the diameter of the downstream end 32 is the same as, or substantially the same as, the inlet width 21.

[0068] As the tapered section 15 moves from the upstream end 30 to the downstream end 32, it has a body 28 having a diameter that gradually decreases or otherwise gradually decreases, while contracting the internal volume within the tapered section 15. Thus, the tapered section 15 has an upstream diameter greater than the chamber width and decreases to a downstream end having a diameter equal to, substantially equal to, or smaller than the chamber width. The contracted diameter of the tapered section 15 increases the pressure of the fluid flowstream as the fluid flowstream enters the gear chamber 20. In one embodiment, this process involves positioning an elongated conduit at the upstream end of the tapered section and introducing a second fluid into the FFS1 from each respective elongated conduit through at least one inlet width (I w The process includes introducing only the first fluid at a position upstream of the inlet, supplying the FFS1 and the second fluid into the inlet 19, 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. In a further embodiment, this process includes forming an mFFS having a CoV of 0.1 to 0.5.

[0069] This disclosure advantageously provides a process for mixing a second fluid (F2), such as an additive, into a polymer melt stream (FFS1) without using an extruder and a static mixer. In one embodiment, the process is achieved by utilizing a liquid additive injector system installed in a conduit that carries the polymer flow to a gear pump. This disclosure also provides a specific gear profile for achieving effective mixing. The desired mixing is achieved by utilizing the shear and mixing provided by the gear pump.

[0070] Examples of embodiments of the present disclosure are provided below, but are not limited to the above. [Examples]

[0071] Table 1 below shows the materials used in the examples.

[0072] [Table 1]

[0073] In one embodiment, apparatus 100 is provided, as shown in Figure 1. Apparatus 100 is similar to apparatus 10 (disclosed earlier), and apparatus 100 includes additional and / or alternative components for evaluating mixing performance.

[0074] The elongated conduit 52 penetrates or otherwise traverses the passage 14 and extends traversing the interior of the passage 14. The elongated conduit 52 extends into the interior of the passage. Multiple spaced partial ports extend along the downstream length of the elongated conduit 52. The apparatus 100 may also include a source of F2, along with piping, valves, and a pump for supplying F2 to the elongated conduit 52. In the case of apparatus 100, the distance between the rotating shaft 26a and the elongated conduit 52 is 7.6 inches (2.5 inches). w The distance between the inlet and the injector is 1.95 I w In the case of apparatus 100, the outlet barrel 16 is 18 inches (6.5 inches). w This is the length of ).

[0075] For evaluation purposes, an elongated conduit 152 is provided, which includes two elongated conduits 156a and 156b that are spaced apart from each other and parallel or substantially parallel to each other, as shown in Figures 6A and 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 from each other. The ports 156 are located on the downstream faces of each elongated conduit 154a and 154b.

[0076] In configuration A, the elongated conduit 152 is oriented vertically within the passage 14 such that the elongated conduits 154a and 154b are parallel or substantially parallel to the respective rotation axes 26a and 26b of the gears 22a and 22b, as shown in Figure 6A.

[0077] In configuration B, the elongated conduit 152 is oriented horizontally within the passage 14 such that the elongated conduits 154a and 154b are perpendicular or substantially perpendicular to the respective rotation axes 26a and 26b of the gear, as shown in Figure 6B.

[0078] In apparatus 100, the pitch diameter of each gear is 2.756 inches. In the gear chamber 20, both (i) the intertooth clearance and (ii) the clearance between the gear tip and the housing are maintained at 0.01 inches. Gears with four different helix angles are provided for evaluation. Gears 122a and 122b have a helix angle of 0° (Figure 7A). Gears 222a and 222b have a helix angle of 7° (Figure 7B). Gears 322a and 322b have a helix angle of 30° (Figure 7C). Gears 422a and 422b have a herringbone pattern (Figure 7D).

[0079] Table 2 below shows the CoV values ​​in the cross-sectional plane at the outlet barrel 16 of the mFFS40. The flow through apparatus 100 is simulated using a modeling technique called Computational Fluid Dynamics (CFD). The CoV values ​​in Table 2 below are generated using CFD (Starccm+V15) and a meshing tool (SCORG). The CoV values ​​are calculated using Equation 1, where the average additive concentration is estimated based on the input mass flow rate of the additive, and the local concentration of the additive is estimated from the CFD results. The CoV values ​​are calculated in the cross-sectional plane perpendicular to the flow stream (downstream from the outlet) at 1.81 I w ) is calculated over the cross-sectional area. As previously mentioned, CoV calculates the ratio of the standard deviation to the mean concentration of the second fluid (F2). The standard deviation and mean concentration values ​​are calculated based on the results of the CFD simulation under the previously mentioned operating conditions. The simulation is run to achieve steady-state conditions when there is no longer any change in the mean and standard deviation of the concentration values ​​over different cross-sectional planes. Since the CFD simulation retains details of the velocity, pressure, temperature, and concentration values ​​in each calculation cell, the standard deviation and mean concentration values ​​in a given cross-sectional area can be calculated.

[0080] [Table 2]

[0081] The CoV value, which indicates the degree of mixing, was lower in the case of 0° injection (configuration A) compared to its 90° injection control (configuration B), and surprisingly, this trend was found to be constant regardless of the gear design profile. Note that lower CoV values ​​indicate better mixing than CoV values ​​below 0.5, which are considered sufficient for most chemical processes (Paul, et al., Handbook of Industrial Mixing, 2003). In addition to the orientation of the injection conduit, the effect of the gear helix angle is also evident. Herringbone gears showed the lowest CoV values, followed by a 0° helix angle (spur gear), and the CoV value increased as the single helix angle increased. With increasing helix angles, the second fluid (additive) tends to accumulate on one side of the outlet conduit due to the pressure gradient facilitated by the single helical gear. However, the additive flow is symmetrical with respect to the herringbone gear due to the dual helix angles (counterclockwise and clockwise) that make the spanwise pressure gradient net zero, and the symmetry provided by gear teeth with different helix angles equidistant from the gear's center plane also ensures optimal performance in additive mixing.

[0082] Figure 9 shows the additive concentration profiles for spur, helical, and herringbone gears for 0° and 90° injection. As previously mentioned, when the additive accumulates on one side, the helical gear promotes preferential flow. However, in the case of the herringbone gear (Figure 8), the flow remains uniform with a continuous contact line (extension) that results in uniform mixing. Therefore, the CoV value of the herringbone gear is generally lower compared to the spur and helical gears.

[0083] It has been found that increasing the helix angle promotes a preferential flow on the suction side of the gear pump. As the teeth disengage from each other, the discharge rate changes along the gear span. Gear profiles with a large helix angle tend to open first on one side, thus resulting in a low-pressure zone. While not bound by any particular theory, this low-pressure zone draws more additive from one side of the upstream C of the gear chamber than from the other side, thereby creating a non-uniform distribution of additive.

[0084] This disclosure is not limited to the embodiments and examples contained herein, but is specifically intended to include some embodiments and modified forms of those embodiments, including combinations of elements of different embodiments, to the extent that they fall within the scope of the following claims.

Claims

1. It is a process, To provide an apparatus, (A) A passage having an interior for receiving a first flowstream (FFS1) containing a molten polymer composition, the passage having an inlet end and an outlet end on the opposite side, (B) Gear pump assembly, (i) Housing, (ii) Gear chamber within the housing, (iii) An inlet that connects the outlet end of the passage to the gear chamber, with a width (I ｗ ) has an entrance, (iv) A plurality of meshing gears mounted to rotate within the gear chamber, each having teeth that engage with each other within the chamber, and (v) A gear pump assembly including an outlet that is in fluid communication with the gear chamber, (C) To provide an apparatus comprising one or more injectors located upstream of the gear pump assembly for adding a second fluid to the first flowstream, wherein the second fluid comprises radical-graftable species and peroxides, the peroxides having an activation temperature, and the injectors are located upstream of the inlet, the process comprising The second fluid is introduced into the FFS1 from each injector at a position upstream of the inlet, The FFS1 and the second fluid are supplied into the inlet, Within the gear chamber, the second fluid is mixed with FFS1 to form a mixed fluid flowstream (mFFS), Discharge the aforementioned mFFS into the curing chamber from the outlet, A process comprising grafting the radical-graftable species onto the polymer in the curing chamber to form a graft polymer.

2. The process according to claim 1, comprising maintaining the temperature of the mFFS below the peroxide activation temperature during the mixing and discharge.

3. The one or more injectors are located upstream of the inlet at a distance of at least half the gear diameter, and the process is The process according to claim 1 or 2, comprising introducing the second fluid from each injector into the FFS1 at a position upstream of the inlet by at least half the diameter of the gear.

4. The process according to any one of claims 1 to 3, comprising heating the mFFS in the curing chamber to a temperature above the peroxide activation temperature.

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