CN117580900A

CN117580900A - Polymer recovery process and product

Info

Publication number: CN117580900A
Application number: CN202280044149.2A
Authority: CN
Inventors: H·玛法德斯; M·C·亨得利; S·D·梅塔; M·康萨尔维; G·梅尔; L·E·科克伦
Original assignee: Equistar Chemicals LP
Current assignee: Equistar Chemicals LP
Priority date: 2021-06-22
Filing date: 2022-06-21
Publication date: 2024-02-20
Also published as: CN117580901A; CN117597385A; CN117580902A; CN117545800A

Abstract

Methods for processing LLDPE recyclates (including but not limited to polyethylene and polypropylene) and compositions derived therefrom are provided. The LLDPE recycle may be visbroken to improve processing characteristics and/or devolatilized to remove waste byproducts to produce a processed LLDPE recycle. The processed LLDPE recyclate is compounded with a pre-consumer polyolefin to produce a blended composition having acceptable or even improved processing characteristics. Such pre-consumer polyolefins may also be visbroken to further tailor the processing characteristics of such polymer blends. The combination of extruder and/or extruder zones may be used in the same or different locations for visbreaking and/or compounding of both the LLDPE recycle and/or the pre-consumer polyolefin.

Description

Polymer recovery process and product

Cross Reference to Related Applications

The present application claims priority from U.S. provisional patent application Ser. No. 63/213,429 entitled "Polymer recovery Process and product (POLYMER RECYCLATE PROCESSES AND PRODUCTS)" filed on 6 month 22 of 2021 and U.S. provisional patent application Ser. No. 63/238,655 entitled "Polymer recovery Process and product" filed on 8 month 30 of 2021, filed on even date 22 of 2021, the contents of which are incorporated herein by reference in their entireties.

Technical Field

The present disclosure relates to the use of extrusion processes alone or in combination with other polyolefins to improve the processing characteristics of polyolefin recyclates. The invention also relates to compositions produced by such processes.

Background

Polyolefins, including polyethylene and polypropylene, are useful in many applications, including packaging for food and other goods, electronics, automotive parts, and various manufactured goods. Waste plastic materials are available from a variety of sources, including differential recycling of municipal plastic waste, which is composed of flexible packaging (cast, blown and BOPP films), rigid packaging, blown bottles and injection molded containers. Generally, two main polyolefin fractions, polyethylene (including HDPE, LDPE, LLDPE) and polypropylene (including homopolymers, random copolymers, heterophasic copolymers) can be obtained by a step of separation from other polymers such as PVC, PET or PS.

The multicomponent nature of the recycled polyolefin or polyolefin fraction may result in low mechanical and optical properties of the manufactured article or polyolefin formulation, wherein a portion of the virgin LLDPE is replaced by recycled polymer. Variations in one or more characteristics of the recycled polyolefin, including but not limited to melt index, high load melt index, melt elasticity, complex viscosity, or combinations thereof, may result in unpredictable mechanical and/or optical properties. In addition, the recovered polyolefin or polyolefin fraction may contain impurities or be contaminated with other components. In addition, the molecular weight, molecular weight distribution, and/or comonomer content of the recovered polyolefin or polyolefin fraction may limit the range of virgin LLDPE into which the recovered polyolefin can be incorporated. Another limitation of using recycled polyolefin may be that these polymers may absorb volatile organic compounds during use, thereby creating an unpleasant odor.

In the case of polyethylene, it may be desirable to separate the polyethylene waste into fractions of predominantly HDPE, predominantly MDPE, predominantly LDPE, predominantly LLDPE or predominantly polypropylene. The present disclosure provides a process for producing a polyolefin composition comprising recycled LLDPE in the context of LLDPE parts, such polyolefin composition having a variety of useful properties. Such disclosed processes can be highly flexible and can be implemented with commonly used equipment and familiar techniques to produce a wide variety of products.

Disclosure of Invention

The present disclosure relates generally to methods for processing polyolefin recyclates, particularly linear low density polyethylene ("LLDPE") recyclates. Such processing includes performing visbreaking conditions in an extruder to convert the LLDPE recycle into a visbroken LLDPE recycle having a reduced weight average molecular weight. In some embodiments, the LLDPE recycle is also subjected to devolatilization conditions to convert the LLDPE recycle into a visbroken LLDPE recycle having a reduced weight average molecular weight and a reduced volatile organic compound ("VOC") content.

Visbreaking conditions include thermal visbreaking and/or peroxidic visbreaking. Thermal visbreaking includes temperature, pressure, and mechanical shear sufficient to cause polymer chain scission to predominate over polymer chain branching or crosslinking. Peroxide visbreaking may occur when peroxide is added to the polymer melt in an extruder and then the peroxide is thermally decomposed to form free radicals, which react with the polymer chain resulting in chain scission. In some embodiments, the visbreaking conditions consist of thermal visbreaking in the absence or substantial absence of oxygen at a temperature at least 180 ℃ above the melting point of the LLDPE.

The devolatilization conditions may include reducing the VOC in the polyolefin by a portion of an extruder having a dense mixing arrangement and a devolatilization zone to enable VOC removal at high temperatures. The devolatilization conditions may be further enhanced by injecting gas into the extruder, distributing the gas in the polymer melt to purge the VOC components, and extracting the gas and purged VOC components by venting and/or vacuum.

In some embodiments, the processed LLDPE recycle may be pelletized into a product at the extruder discharge. In other embodiments, the processed LLDPE recycle may be fed to a second extruder for compounding or blending with virgin LLDPE. In yet other embodiments, the virgin LLDPE can be a polyolefin powder product, pelletized polyolefin, or polyolefin melt from a polymerization apparatus, which is the product of a third extruder. In any of the embodiments in this paragraph, the virgin LLDPE may have been subjected to a visbreaking process prior to addition to the second reactor.

In some embodiments, virgin LLDPE is fed to a third extruder, and the polymer melt from the third extruder is co-fed to the second extruder along with the processed LLDPE recycle melt.

In some embodiments, a composition is provided wherein the composition is or comprises a polymer blend of 5wt.% to 90wt.% of the LLDPE recycle and 10wt.% to 95wt.% of the virgin LLDPE, wherein all weight percentages are based on the total weight of the polymer blend, and one or both of the LLDPE recycle feedstock and the virgin LLDPE are visbroken. Visbreaking may be thermal visbreaking and/or peroxidic visbreaking.

The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other film structures and/or processes for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of manufacture, together with further objects and advantages will be better understood from the following description.

Drawings

The claimed subject matter may be understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements, and in which:

FIG. 1 is a simplified flow diagram of a process for obtaining a processed LLDPE recycle according to an embodiment of the present invention;

FIG. 2 is a simplified flow diagram of a process for obtaining a blend of processed LLDPE recycle and virgin LLDPE using two extruders in accordance with an embodiment of the present invention;

FIG. 3 is a simplified flow diagram of a process for obtaining a blend of processed LLDPE recycle and virgin LLDPE using three extruders in accordance with an embodiment of the invention;

FIG. 4 is a superimposed graph showing the effect of LLDPE visbreaking on complex viscosity according to an embodiment of the present invention; and

fig. 5 is a superimposed graph showing the effect of LLDPE visbreaking on molecular weight according to an embodiment of the invention.

While the disclosed processes and compositions are susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail herein. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

Detailed Description

Illustrative embodiments of the subject matter claimed below will now be disclosed. In the interest of clarity, some features of some actual implementations may not be described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort, even if complex and time-consuming, would be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

The words and phrases used herein should be understood and interpreted to have a meaning consistent with the understanding of those words and phrases by those skilled in the relevant art. The special definition of a term or phrase, i.e., a definition that is different from the ordinary and customary meaning as understood by those skilled in the art, is intended to be implied by consistent usage of the term or phrase herein. To the extent that a term or phrase is intended to have a special meaning, i.e., a meaning other than the broadest meaning as understood by those skilled in the art, such special or clear definition is expressly set forth in the specification in a definitional manner that provides a special or clear definition for the term or phrase. It must also be noted that, as used in the specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless otherwise specified.

For example, the following discussion contains a non-exhaustive list of definitions of several specific terms used in the present invention (other terms may be defined or set forth in a manner defined elsewhere herein). These definitions are intended to clarify the meaning of the terms used herein. These terms are used in a manner consistent with their ordinary meaning, but for clarity, their definition will be specifically explained herein.

Definition of the definition

As used herein, "antioxidant" means a compound that inhibits oxidation, which is a chemical reaction that can produce free radicals and chain reactions.

As used herein, "compounding conditions" means temperature, pressure, and shear conditions that are practiced in an extruder to provide intimate mixing of two or more polymers and optional additives to produce a substantially uniform polymer product.

As used herein, "devolatilization conditions" means subjecting the polymer melt to injection and evacuation of purge gas in an extruder, heating, physical mixing, pressure reduction by venting or application of vacuum, or a combination thereof. The devolatilization conditions implemented in the extruder are sufficient to reduce the VOC of the polymer fed to the extruder by a predetermined percentage and/or to a predetermined VOC target of the polymer exiting the extruder. The devolatilization conditions involve the reduction of VOCs in the polyolefin by a portion of an extruder having a dense mixing arrangement and a devolatilization section to enable VOC removal at high temperatures. The devolatilization conditions may be further enhanced by injecting gas into the extruder, distributing the gas in the polymer melt to purge the VOC components, and extracting the gas and purged VOC components by venting or vacuum.

As used herein, "devolatilized LLDPE recycle" means a product obtained by subjecting a LLDPE recycle feedstock to devolatilization conditions as described herein.

"extruder" as used herein in the context of "first extruder", "second extruder" and "third extruder" means in some embodiments a separate extrusion device, and in other embodiments separate sections within a single extrusion device. In some embodiments, the first extruder and the second extruder are separate machines. In some embodiments, the first extruder and the second extruder are separate sections in a single machine. In some embodiments, the second extruder and the third extruder are separate machines. In some embodiments, the second extruder and the third extruder are separate sections in a single machine. In some embodiments, the first extruder, the second extruder, and the third extruder are separate machines. In some embodiments, the first extruder, the second extruder, and the third extruder are separate sections in a single machine. As used herein, "extruder" includes an extruder capable of continuous processing under visbreaking conditions, compounding conditions, melting conditions, or devolatilizing conditions, one or more Any device or combination of devices for seeding polyolefin, including but not limited to a Farrel continuous mixer (FCM ^TM Mixers, available from Farrel corporation, an Suoni, ct).

"HDPE" as used herein means that produced in a suspension, solution, slurry or gas phase polymerization process and having a density of 0.940g/cm ³ To 0.970g/cm ³ Ethylene homopolymers and ethylene copolymers within the scope.

As used herein, "LLDPE recycle feedstock" means a LLDPE recycle after collection and sorting but before being subjected to the process disclosed herein.

"LLDPE recycle" as used herein means post-consumer recovery ("PCR") LLDPE and/or post-industrial recovery ("PIR") LLDPE. The polyolefin recyclates are derived from end products that have completed their life cycle as consumer products and would otherwise be disposed of as waste (e.g., polyethylene water bottles), or from plastic waste generated from waste of industrial processes. Post-consumer polyolefins include polyolefins that have been collected in commercial and residential recycling programs, including flexible packaging (cast film, blown film, and BOPP film), rigid packaging, blown bottles, and injection molded containers. Typically, two main polyolefin fractions are obtained by a step of separation from other polymers such as PVC, PET or PS, namely polyethylene recyclates (including HDPE, MDPE, LDPE and LLDPE) and polypropylene recyclates (including homopolymers, random copolymers and heterophasic copolymers). The polyethylene recycle may be further separated to recover a fraction having LLDPE as the major component. In addition to contamination from different polymers, LLDPE recyclates often contain other impurities such as PMMA, PC, wood, paper, textiles, cellulose, food, and other organic waste, many of which can cause LLDPE recyclates to have unpleasant odors before and after typical processing.

"LDPE" as used herein means produced in a high pressure radical polymerization and having a density of 0.910g/cm ³ To 0.940g/cm ³ Ethylene homopolymers and ethylene copolymers within the scope.

"LLDPE" as used herein means produced in a suspension, solution, slurry or gas phase polymerization processAnd a density of 0.910g/cm ³ To 0.940g/cm ³ Ethylene copolymers within the scope.

As used herein, "MDPE" means produced in a suspension, solution, slurry or gas phase polymerization process and having a density of 0.925g/cm ³ To 0.940g/cm ³ Ethylene copolymers within the scope.

"melt conditions" as used herein means the temperature, pressure and shear conditions, alone or in combination with one another, required to produce a polymer melt from a feed of polymer pellets or powder.

As used herein, "processed LLDPE recycle" means a product obtained by subjecting a LLDPE recycle feedstock to visbreaking conditions as described herein or to visbreaking conditions followed by devolatilization conditions.

"virgin LLDPE" as used herein is a pre-consumer polyolefin. The pre-consumer polyolefin is a polyolefin product obtained directly or indirectly from petrochemical feedstock fed to a polymerization apparatus. The pre-consumer polyolefin may be subjected to post-polymerization processes such as, but not limited to, extrusion, pelletization, visbreaking, and/or other processing that is completed before the product reaches the end consumer. In some embodiments, the virgin LLDPE has a single thermal history. In some embodiments, the virgin LLDPE has more than one thermal history. In some embodiments, the virgin LLDPE does not include additives. In some embodiments, the virgin LLDPE includes an additive.

As used herein, "visbreaking conditions" means thermal visbreaking and/or peroxidic visbreaking. Thermal visbreaking includes temperature, pressure, and/or mechanical shear sufficient to break polymer chains instead of branching or crosslinking the polymer chains. Peroxide visbreaking occurs when peroxide is added to the polymer melt in an extruder and then the peroxide is thermally decomposed to form free radicals, which react with the polymer chains resulting in chain scission. As used herein, visbroken polymers will have lower number average and weight average molecular weights, narrower molecular weight distributions, higher melt indices, and higher high load melt indices. In some embodiments, the visbreaking conditions consist of performing thermal visbreaking at a temperature in the range of greater than or equal to 300 ℃, or 320 ℃ to 400 ℃, in the absence or substantial absence of oxygen.

As used herein, "visbreaking" means heat/chemical treatment of a polymer such that the M of LLDPE so treated _n 、M _w And MWD (M) _w /M _n ) Reduced melt index I ₂ (ASTM D-1238, 2.16kg at 190 ℃ C.) and high load melt index I ₂₁ (ASTM D-1238, 21.6kg at 190 ℃ C.). The application of high temperature and/or the addition of a free radical source (such as a peroxide) to polyolefin materials can result in degradation of the polymer chains and a decrease in the average molecular weight of the polymer. At the same time, the molecular weight distribution becomes narrow. When such processes are deliberately conducted to alter the properties of the polymer, these practices are commonly referred to as "visbreaking".

As used herein, "visbroken LLDPE recycle" means a product obtained by subjecting a LLDPE recycle feedstock to visbreaking conditions as described herein.

Processing LLDPE recycle feedstock

In fig. 1, a flow diagram 100 includes a visbreaking extruder 110 having a visbreaking zone 115 and an optional devolatilization zone 120. The LLDPE recycle feedstock 125 is added to the visbreaking extruder 110 near the inlet end of the extruder. LLDPE recycle is pumped through the extruder 110 by one or more rotating screw drivers in the barrel of the visbreaking extruder 110. The length of visbreaking extruder 110 is divided into one or more zones. Each zone may have one or more of the following: a specified pitch on the screw drive, inlets 130, 135 for injecting gas, vents or vacuum connections 140 for exhausting gas, means for adding or exhausting heat, inlets 145 for injecting peroxide, and inlets for injecting additives to impart preselected process conditions including, but not limited to, pressure, temperature, and/or shear.

Fig. 1 shows an embodiment having both a visbreaking zone 115 and an optional devolatilization zone 120. Other embodiments may have only visbreaking zone 115 without devolatilization zones. The process conditions in visbreaking extruder 110 may be further controlled by the rotational speed of the screw drive. The processed LLDPE recycle 150 is discharged near the discharge port of the visbreaking extruder 110 for further processing or pelletization.

LLDPE recycle feedstock

In some embodiments, the LLDPE recycle feedstock is derived from an ethylene homopolymer, units derived from ethylene, and units derived from one or more C' s ₃ -C ₁₂ Copolymers of units of alpha-olefins, copolymers of units derived from ethylene and units derived from one or more alpha-mono-olefins. Such C ₃ -C ₁₂ Alpha-olefins include, but are not limited to, substituted or unsubstituted C ₃ To C ₁₂ Alpha olefins such as propylene, butene, pentene, hexene, heptene, octene, nonene, decene, undecene, dodecane and isomers thereof. When present, the comonomer may be present in an amount of up to 20wt%, 15wt%, 10wt% or 5wt%. The LLDPE recycle feedstock may be derived as part of a post consumer recycled polyolefin and/or an post industrial recycled polyolefin consisting essentially of LLDPE recycle, where "essentially" means greater than or equal to 80wt%, greater than or equal to 85wt%, greater than or equal to 90wt% or greater than or equal to 95wt%, based on the total weight of the LLDPE recycle feedstock.

Such ethylene homopolymers and/or copolymers may be produced in suspension, solution, slurry or gas phase processes using known equipment and reaction conditions. In some embodiments, the polymerization temperature is in the range of about 0 ℃ to about 300 ℃ at atmospheric pressure, subatmospheric pressure, or superatmospheric pressure.

Slurry or solution polymerization systems may utilize subatmospheric or superatmospheric pressures and temperatures in the range of from about 40 ℃ to about 300 ℃. An exemplary liquid phase polymerization system is described in U.S. Pat. No. 3,324,095, the disclosure of which is incorporated herein by reference in its entirety. Liquid phase polymerization systems typically include a reactor in which olefin monomer and catalyst composition are added and which contains a liquid reaction medium for dissolving or suspending the polyolefin. The liquid reaction medium may consist of bulk liquid monomers or inert liquid hydrocarbons which do not react under the polymerization conditions employed. Although such an inert liquid hydrocarbon need not be used as a solvent for the catalyst composition or the polymer obtained by the process, it is generally used as a solvent for the monomers used in the polymerization. Inert liquid hydrocarbons suitable for this purpose are isopentane, hexane, cyclohexane, heptane, benzene, toluene, and the like. The reactive contact between the olefin monomer and the catalyst composition should be maintained by continuous stirring or agitation. The reaction medium containing the olefin polymer product and unreacted olefin monomer is continuously withdrawn from the reactor. The olefin polymer product is separated and unreacted olefin monomer and liquid reaction medium are recycled to the reactor.

The gas phase polymerization system can utilize superatmospheric pressure in the range of from 1psig (6.9 kPag) to 1,000psig (6.9 Mpag), 50psig (344 kPag) to 400psig (2.8 Mpag), or 100psig (689 kPag) to 300psig (2.1 Mpag), and a temperature in the range of from 30 ℃ to 130 ℃ or 65 ℃ to 110 ℃. The gas phase polymerization system may be a stirred or fluidized bed system. In some embodiments, the gas phase fluidized bed process is performed by continuously passing a stream containing one or more olefin monomers through a fluidized bed reactor under reaction conditions and in the presence of a catalyst composition at a velocity sufficient to maintain a bed of solid particles in suspension. A stream containing unreacted monomers is continuously withdrawn from the reactor, compressed, cooled, optionally partially or fully condensed, and recycled to the reactor. Product is withdrawn from the reactor and make-up monomer is added to the recycle stream. Any gas inert to the catalyst composition and reactants may also be present in the gas stream, as desired for temperature control of the polymerization system.

In some embodiments, ziegler-Natta (ZN) catalysts are used. Such catalysts are based on a group IVB transition metal compound and an organoaluminum compound (cocatalyst). Such transition metals include, but are not limited to, ti, zr, and Hf. Non-limiting examples of ZN catalyst systems include TiCl ₄ +Et ₃ Al and TiCl ₃ +AlEt ₂ Cl. The LLDPE homopolymers and/or copolymers have some long chain branching and 0.910g/cm ³ To 0.940g/cm ³ Density in the range.

LLDPE recycle feed derived from LLDPE as described above can be characterized as having:

i) At 0.910g/cm ³ To 0.940g/cm ³ Or 0.915g/cm ³ To 0.935g/cm ³ Density in the range;

ii) a melt index (2.16 kg,190 ℃) of less than or equal to 5.0g/10 min;

iii) A molecular weight distribution (M) of greater than or equal to 5.0, greater than or equal to 7.0, greater than or equal to 10.0, or greater than or equal to 15.0 _w /M _n )；

iv) a weight average molecular weight ("M") of greater than or equal to 85,000 daltons, greater than or equal to 120,000 daltons, greater than or equal to 180,000 daltons, or greater than or equal to 200,000 daltons, and/or less than or equal to 500,000 daltons, less than or equal to 400,000 daltons, less than or equal to 350,000 daltons, or less than or equal to 250,000 daltons _w1 ""; and

v) a melt elasticity ("ER") of greater than or equal to 0.5.

In some embodiments, in addition to the above characteristics, the LLDPE recycle feedstock can be characterized as having one or more of the following:

vi) a first VOC content;

vii) first high load melt index (I) ₂₁ ，21.6kg，190℃)；

viii) first melt index ratio (MIR, I ₂₁ /I ₂ )；

ix) a first long chain branching parameter (g') in the range of 0.85 to 1.00, 0.90 to 0.99 or 0.92 to 0.98;

x) a first overall polydispersity ratio (PDR);

xi) first complex viscosity ratioWherein->Is complex viscosity at 0.1 rad/s and +.>Is a complex viscosity at 100 rad/sec, both at a temperature of 190 ℃; and

xii) first intrinsic viscosity.

Visbreaking extruder

The LLDPE recycle feedstock is fed into a first extruder and subjected to visbreaking conditions and optionally devolatilizing conditions.

Visbreaking

Visbreaking conditions are carried out in the visbreaking zone of the first extruder and are tailored for LLDPE. In some embodiments, visbreaking conditions mean thermal visbreaking and/or peroxidic visbreaking. In some embodiments, visbreaking conditions consist of thermal visbreaking, wherein the temperature in the visbreaking zone is greater than or equal to 300 ℃, under which the chain scission reaction is believed to exceed the long chain branching and/or crosslinking reaction. In some embodiments, the temperature in the visbreaking zone may be in the range of 320 ℃ to 500 ℃, 340 ℃ to 480 ℃, or 360 ℃ to 460 ℃. In some embodiments, the apparatus at the discharge of the first extruder monitors the rheology (I ₂ 、I ₂₁ Viscosity, melt elasticity, complex viscosity ratio, etc.) to measure and assist in controlling visbreaking. In some embodiments, wherein the antioxidant addition is used in combination with visbreaking, the antioxidant addition point is at a location on the first extruder after a substantial portion of the visbreaking reaction has occurred. In some embodiments, the visbreaking conditions consist of performing thermal visbreaking in the absence or substantial absence of oxygen, wherein the substantial absence of oxygen means less than or equal to 1.0wt%, less than or equal to 0.10wt%, or less than or equal to 0.01wt%, based on the total weight of the polymers in the extruder. In some embodiments, the visbreaking extruder includes one or more melt filters.

Devolatilization of

The devolatilization conditions are optionally carried out in a first extruder and involve reducing the VOC in the LLDPE recycle feedstock through a portion of the extruder having a dense mixing arrangement and devolatilization zone to enable VOC removal at high temperatures. The devolatilization conditions may be further enhanced by: injecting a purge gas, such as, but not limited to, nitrogen, carbon dioxide, water, or a combination thereof, into the extruder; distributing a gas in the polymer melt to remove VOC components; and extracting the gas and the purged VOC components by venting and/or vacuum.

Processed LLDPE recyclates

The processed LLDPE recycle is discharged from the discharge outlet of the visbreaking extruder, where "processed" means that the LLDPE recycle feedstock is subjected to visbreaking conditions or to devolatilization conditions after being subjected to visbreaking conditions. As described above, the processed LLDPE recycle can be characterized as having:

i) A density, wherein the ratio of the density of the processed LLDPE recycle to the density of the LLDPE recycle feedstock is greater than or equal to 1.0;

ii) melt index (I) ₂ ) Wherein the ratio of the melt index of the processed LLDPE recycle to the melt index of the LLDPE recycle feed is greater than or equal to 5.0 and/or the processed LLDPE recycle has a melt index (I2) greater than or equal to 5.0g/10 minutes;

iii) A molecular weight distribution wherein the ratio of the molecular weight distribution of the processed LLDPE recycle to the molecular weight distribution of the LLDPE recycle feedstock is less than or equal to 0.8 and/or the molecular weight distribution of the processed LLDPE recycle is less than or equal to 5.0;

iv) weight average molecular weight ("M _w2 ") wherein the ratio of the weight average molecular weight of the processed LLDPE recycle to the weight average molecular weight of the LLDPE recycle feedstock is less than or equal to 0.90 or less than or equal to 0.80; and

v) melt elasticity ("ER"), wherein the ratio of ER of the processed LLDPE recycle to ER of the LLDPE recycle feedstock is less than or equal to 0.50, less than or equal to 0.40, or less than or equal to 0.30 and/or the second melt elasticity is less than 0.5.

In some embodiments, in addition to the foregoing characteristics, the processed LLDPE recycle may be characterized as having one or more of the following:

vi) VOC content, wherein the ratio of VOC content of the processed LLDPE recycle to VOC content of the LLDPE recycle feedstock is less than or equal to 0.9, 0.8, 0.7, 0.6, or 0.5, each, alone or in combination, having a lower limit of greater than or equal to 0.1;

vii) high load melt index (I) ₂₁ 21.6kg,190 ℃), wherein the ratio of the high load melt index of the processed LLDPE recycle to the high load melt index of the LLDPE recycle feedstock is greater than or equal to 2.0, greater than or equal to 3.0, or greater than or equal to 4.0;

viii) melt index ratio (MIR, I ₂₁ /I ₂ ) Wherein the MIR of the processed LLDPE recycle is less than or equal to 0.90, less than or equal to 0.85, or less than or equal to 0.80 with the MIR of the LLDPE recycle feedstock;

ix) a long chain branching parameter (g '), wherein the ratio of g ' of the processed LLDPE recycle to g ' of the LLDPE recycle feedstock is less than or equal to 1.0;

x) a first long chain branching index ("LCBI") greater than or equal to 0, and the processed LLDPE recycle has an LCBI greater than 0;

xi) an overall polydispersity ratio (PDR), wherein the ratio of PDR of the processed LLDPE recycle to PDR of the LLDPE recycle feedstock is less than or equal to 0.90, less than or equal to 0.80, or less than or equal to 0.70;

xii) complex viscosity ratioWherein the ratio of the complex viscosity ratio of the processed LLDPE recycle to the complex viscosity ratio of the LLDPE recycle feed is less than or equal to 0.7, less than or equal to 0.6, or less than or equal to 0.5, and/or the complex viscosity ratio of the processed LLDPE recycle is less than or equal to 3.0 or less than or equal to 2.0, and%>Is complex viscosity at 0.1 rad/s, and +.>Is a complex viscosity at 100 rad/sec, both at a temperature of 190 ℃; and

xiii) an intrinsic viscosity [ η ] wherein the ratio of the intrinsic viscosity of the processed LLDPE recycle to the intrinsic viscosity of the LLDPE recycle feedstock is less than or equal to 0.90, less than or equal to 0.80, or less than or equal to 0.70.

Blending of processed LLDPE recycle and polyolefin blend components-two extruders

In fig. 2, the flow diagram 200 includes a visbreaking extruder 210 and a compounding extruder 255. The embodiment of the invention shown in fig. 2 includes a visbreaking extruder 210 having a visbreaking zone 215 and a devolatilizing zone 220. The LLDPE recycle feedstock 225 is added to the visbreaking extruder 210 near the inlet end of the extruder. The LLDPE recycle feedstock 225 is pumped through the visbreaking extruder 210 by one or more rotating screw drivers in the barrel of the visbreaking extruder 210. The length of visbreaking extruder 210 is divided into one or more zones. Each zone may have one or more of the following: a specified pitch on the screw drive, inlets 230, 235 for injection of gas, vents or vacuum connections 240 for evacuation of gas, means for adding or evacuating heat, inlets 245 for injection of peroxide, and inlets for injection of additives to impart preselected process conditions including, but not limited to, pressure, temperature, and shear.

Fig. 2 shows an embodiment having both visbreaking zones 215 and devolatilization zones 220. Other embodiments may independently have the visbreaking zone 215 or the devolatilization zone 220 without the other. The process conditions in visbreaking extruder 210 may be further controlled by the rotational speed of the screw drive. The processed LLDPE recycle 250 is discharged near the discharge port of the visbreaking extruder 210 for further processing.

The embodiment of fig. 2 includes a second extruder 255 having a compounding zone 260. The processed LLDPE recycle 250 is added as a first blend component with the polyolefin blend component 252 to a compounding extruder 255 near the inlet end of the extruder and subjected to compounding conditions. The polyolefin blend component 252 includes virgin polyolefin, polyolefin recycle feedstock, processed polyolefin recycle, or a combination thereof. In some embodiments, the virgin polyolefin comprises virgin HDPE, virgin LLDPE, virgin HDPE, virgin MDPE, virgin polypropylene, or a combination thereof. In some embodiments, the polyolefin recycle feedstock comprises an LDPE recycle feedstock, an LLDPE recycle feedstock, an HDPE recycle feedstock, an MDPE recycle feedstock, a polypropylene recycle feedstock, or a combination thereof. In some embodiments, the processed polyolefin recycle comprises a processed LDPE recycle, a second processed LLDPE recycle, a processed HDPE recycle, a processed MDPE recycle, a processed polypropylene recycle, or a combination thereof. In some embodiments, the polyolefin blend component includes virgin LLDPE, LLDPE recycle raw materials, processed LLDPE recycle, or combinations thereof. The mixture of the LLDPE recycle 250 and the polyolefin blend component 252 is pumped through the compounding extruder 255 by one or more rotating screw drivers in the barrel of the extruder 255. One or more additional inlets near the inlet end of the extruder are used to add antioxidants 265 and/or other components 270. The length of compounding extruder 255 may be divided into one or more zones. Each zone may have one or more of the following: a specified pitch on the screw drive, means for adding or removing heat, an inlet for injecting additives, and a vent or vacuum connection 275 for removing gas to impart preselected process conditions including, but not limited to, pressure, temperature, and shear. The blend 280 of processed LLDPE recycle 250 and polyolefin blend component 252 is discharged near the discharge outlet of compounding extruder 255 for further processing or pelletization.

In some embodiments, the polyolefin blend component may be a polyolefin powder product, a pelletized polyolefin, or a polyolefin melt from a polymerization apparatus, which is the product exiting the third extruder. In some of these embodiments, the polymerization apparatus comprises two, three, or more polymerization reactors and/or two, three, or more polymerization zones within a polymerization reactor. More specific polymerization apparatus embodiments include, but are not limited to, two or three gas phase fluidized bed reactors in series, two or three slurry phase reactors in series, and a gas phase fluidized bed reactor in series with a multi-zone circulating reactor.

In some embodiments, the amount of polyolefin blend components (which may themselves comprise two or more polymers) is determined based on a logarithmic mixing rule, wherein the blend components satisfy the following equation:

wherein:

MFR is I ₂ 、I ₂₁ Or other selected melt index;

MFR _{blends of} A target MFR that is the final blend product;

n is the number of components in the blend; and

i is the i-th component of the n-component blend.

Blend components

The first blend component is a processed LLDPE recycle produced from a visbreaking extruder. The second blend component includes virgin polyolefin, polyolefin recycle feedstock, processed polyolefin recycle, or a combination thereof. In some embodiments, the virgin polyolefin comprises virgin LDPE, virgin LLDPE, virgin HDPE, virgin polypropylene, or a combination thereof. In some embodiments, the polyolefin recycle feedstock comprises an LDPE recycle feedstock, an LLDPE recycle feedstock, an HDPE recycle feedstock, a polypropylene recycle feedstock, or a combination thereof. In some embodiments, the processed polyolefin recycle comprises a processed LDPE recycle, a second processed LLDPE recycle, a processed HDPE recycle, a processed polypropylene recycle, or a combination thereof. In some embodiments, the polyolefin blend component includes virgin LLDPE, LLDPE recycle raw materials, processed LLDPE recycle, or combinations thereof. When the processed LLDPE recycle is blended with another processed LLDPE recycle, the first LLDPE recycle will have at least one parameter distinguishing it from the second processed LLDPE recycle.

-Virgin LLDPE

In some embodiments, the virgin LLDPE is from an ethylene homopolymer, units derived from ethylene, and units derived from one or more C' s ₃ -C ₁₂ Copolymers of units of alpha-olefins, copolymers of units derived from ethylene and units derived from one or more alpha-mono-olefins. Such C ₃ -C ₁₂ Alpha-olefins include, but are not limited to, substituted or unsubstituted C ₃ To C ₁₂ Alpha olefins such as propylene, butene, pentene, hexene, heptene, octene, nonene, decene, undecene, dodecane and isomers thereof. When present, the comonomer may be present in an amount of up to 20wt%, 15wt%, 10wt% or 5 wt%.

The virgin LLDPE can be characterized as having:

ii) a melt index (2.16 kg,190 ℃) in the range of 1.0g/10 min to 100g/10 min, 2.0g/10 min to 80g/10 min or 3.0g/10 min to 50g/10 min.

iii) A molecular weight distribution (M) of greater than 15 _w /M _n ) The method comprises the steps of carrying out a first treatment on the surface of the And

iv) a weight average molecular weight of less than or equal to 250,000 daltons, less than or equal to 200,000 daltons, less than or equal to 150,000 daltons, or less than or equal to 100,000 daltons.

-LLDPE recycle feedstock

In some embodiments, the LLDPE recycle feedstock is derived from an ethylene homopolymer, units derived from ethylene, and units derived from one or more C' s ₃ -C ₁₂ Copolymers of units of alpha-olefins, copolymers of units derived from ethylene and units derived from one or more alpha-mono-olefins. Such C ₃ -C ₁₂ Alpha-olefins include, but are not limited to, substituted or unsubstituted C ₃ To C ₁₂ Alpha olefins such as propylene, butene, pentene, hexene, heptene, octene, nonene, decene, undecene, dodecane and isomers thereof. When present, the comonomer may be present in an amount of up to 20wt%, 15wt%, 10wt% or 5wt%. The LLDPE recycle feedstock may be derived as part of a post consumer recycled polyolefin and/or an post industrial recycled polyolefin consisting essentially of LLDPE recycle, where "essentially" means greater than or equal to 80wt%, greater than or equal to 85wt%, greater than or equal to 90wt%, or greater than or equal to 95wt%, based on the total weight of the LLDPE recycle feedstock.

ii) a melt index (2.16 kg,190 ℃) of less than or equal to 5.0g/10 min;

v) a melt elasticity ("ER") of greater than or equal to 0.5.

vi) a first VOC content;

vii) first high load melt index (I) ₂₁ ，21.6kg，190℃)；

viii) first melt index ratio (MIR, I ₂₁ /I ₂ )；

x) a first overall polydispersity ratio (PDR);

xi) first complex viscosity ratioWherein->Is complex viscosity at 0.1 rad/s and +.>Is at 100 rad/sComplex viscosity at 190 ℃; and

xii) first intrinsic viscosity.

-Processed LLDPE recyclates

Compounding extruder

The processed LLDPE recycle and polyolefin blend components are fed into a second extruder or mixer, wherein the blend is subjected to compounding conditions. Compounding conditions are carried out in the compounding zone of the second extruder or mixer and are tailored to the particular polyolefin and optional additives mixture. Temperature, pressure and shear conditions sufficient to provide intimate mixing of the processed LLDPE recycle and virgin LLDPE and optional additives are conducted in a second extruder or mixer to produce a substantially homogeneous polymer blend of the processed LLDPE recycle and virgin LLDPE. In some embodiments, the compounding conditions include a temperature in the compounding zone of less than or equal to 300 ℃, less than or equal to 250 ℃, or less than or equal to 200 ℃. In some embodiments, the temperature in the compounding zone may be in the range of 125 ℃ to 195 ℃, 130 ℃ to 180 ℃, or 135 ℃ to 165 ℃.

Blend of processed LLDPE recycle and polyolefin blend components

In some embodiments, the blend includes 5wt.% to 90wt.%, 10wt.% to 80wt.%, 15wt.% to 70wt.%, 20wt.% to 60wt.%, or 25wt.% to 50wt.% of the processed LLDPE recycle and 10wt.% to 95wt.%, 20wt.% to 90wt.%, 30wt.% to 85wt.%, 40wt.% to 80wt.%, or 50wt.% to 75wt.% of the polyolefin blend component, respectively, wherein all weight percentages are based on the total weight of the polymer blend. In some embodiments, the virgin LLDPE is visbroken. Such visbreaking of virgin LLDPE may be thermal visbreaking and/or peroxidic visbreaking. In some embodiments, such visbreaking conditions of the virgin LLDPE consist of thermal visbreaking in the absence or substantial absence of oxygen at a temperature above the melting point of the LLDPE, greater than or equal to 300 ℃, or in the range of 320 ℃ to 400 ℃.

In some embodiments, the blend of the processed LLDPE recycle and the polyolefin blend component is combined or independent of the preceding paragraphComprises a bimodal polymer wherein the processed LLDPE recycle product has a weight average molecular weight ("M _w3 "), the polyolefin blend component has a weight average molecular weight (" M ") _w4 ""; and M is _w3 /M _w4 Less than or equal to 0.9, 0.8, 0.7, 0.6, or 0.5, or alternatively greater than or equal to 1.1, 1.25, 1.5, 1.75, or 2.0.

Blending-three extruders for processed LLDPE recycle and polyolefin blend components

In fig. 3, flow chart 300 includes visbreaking extruder 310, melt extruder 357, and compounding extruder 355. The embodiment of the invention shown in fig. 3 includes a visbreaking extruder 310 having a visbreaking zone 315 and a devolatilizing zone 320. LLDPE recycle feedstock 325 is added to visbreaking extruder 310 near the inlet end of the extruder. LLDPE recycle feedstock 325 is pumped through visbreaking extruder 310 by one or more rotating screw drivers in the barrel of visbreaking extruder 310. The length of visbreaking extruder 310 is divided into one or more zones. Each zone may have one or more of the following: a specified pitch on the screw drive, inlets 330, 335 for injecting gas, vents or vacuum connections 340 for exhausting gas, means for adding or exhausting heat, inlet 345 for injecting peroxide, and inlet for injecting additives to impart preselected process conditions including, but not limited to, pressure, temperature, and shear.

Fig. 3 shows an embodiment having both visbreaking zone 315 and devolatilization zone 320. Other embodiments may independently have the visbreaking zone 315 or the devolatilization zone 320 without the other. The process conditions in visbreaking extruder 310 may be further controlled by the rotational speed of the screw drive. The processed LLDPE recycle 350 is discharged near the discharge port of the visbreaking extruder 310 for further processing.

The embodiment of fig. 3 includes a second extruder 355 having a compounding zone 360 and a third extruder 357 having a melting zone 362. Third blend component 383 is added to melt extruder 357 near the extruder inlet end, optionally with antioxidants 365 and other components 370. The polyolefin blend component 352 includes virgin polyolefin, polyolefin recycle feedstock, processed polyolefin recycle, or a combination thereof. In some embodiments, the virgin polyolefin comprises virgin LDPE, virgin LLDPE, virgin HDPE, virgin MDPE, virgin polypropylene, or a combination thereof. In some embodiments, the polyolefin recycle feedstock comprises an LDPE recycle feedstock, an LLDPE recycle feedstock, an HDPE recycle feedstock, an MDPE recycle feedstock, a polypropylene recycle feedstock, or a combination thereof. In some embodiments, the processed polyolefin recycle comprises a processed LDPE recycle, a second processed LLDPE recycle, a processed HDPE recycle, a processed MDPE recycle, a processed polypropylene recycle, or a combination thereof. In some embodiments, the polyolefin blend component includes virgin LLDPE, LLDPE recycle raw materials, processed LLDPE recycle, or combinations thereof. The mixture of the third blend component 352 and optional antioxidants 365 and/or other components 370 is pumped through the melt extruder 357 by one or more rotating screw drivers in the barrel of the melt extruder 357. The length of the melt extruder 357 may be divided into one or more zones. Each zone may have one or more of the following: a specified pitch on the screw drive, means for adding or removing heat, an inlet for injecting additives, and a vent or vacuum connection for removing gas to impart preselected process conditions including, but not limited to, pressure, temperature, and shear. The melt of polyolefin blend component 352 is discharged at a discharge port near melt extruder 357 for further processing or pelletization.

The processed LLDPE recycle 350 is added to a compounding extruder 355 near the inlet end of the extruder along with a melt of a polyolefin blend component 352. The mixture of the processed LLDPE recycle 350 and the polyolefin blend component 352 is pumped through the compounding extruder 355 by one or more rotating screw drivers in the barrel of the compounding extruder 355, and the mixture is subjected to compounding conditions. The length of compounding extruder 355 may be divided into one or more zones. Each zone may have one or more of the following: a specified pitch on the screw drive, means for adding or removing heat, an inlet for injecting additives, and an exhaust port and/or vacuum connection for exhausting gas 375 to impart preselected process conditions including, but not limited to, pressure, temperature, and shear. The blend 380 of the melt of the processed LLDPE recycle 350 and the polyolefin blend component 352 is discharged near the discharge port of the compounding extruder 355 for further processing or pelletization.

wherein:

MFR is I ₂ 、I ₂₁ Or other selected melt index;

MFR _{blends of} A target MFR that is the final blend product;

n is the number of components in the blend; and

i is the i-th component of the n-component blend.

Blend components

The first blend component is a processed LLDPE recycle from a visbreaking extruder production. The second blend component includes virgin polyolefin, polyolefin recycle feedstock, processed polyolefin recycle, or a combination thereof. In some embodiments, the virgin polyolefin comprises virgin LDPE, virgin LLDPE, virgin HDPE, virgin MDPE, virgin polypropylene, or a combination thereof. In some embodiments, the polyolefin recycle feedstock comprises an LDPE recycle feedstock, an LLDPE recycle feedstock, an HDPE recycle feedstock, an MDPE recycle feedstock, a polypropylene recycle feedstock, or a combination thereof. In some embodiments, the processed polyolefin recycle comprises a processed LDPE recycle, a second processed LLDPE recycle, a processed HDPE recycle, a processed MDPE recycle, a processed polypropylene recycle, or a combination thereof. In some embodiments, the second blend component comprises virgin LLDPE, a LLDPE recycle feedstock, a processed LLDPE recycle, or a combination thereof. When the processed LLDPE recycle is blended with another processed LLDPE recycle, the first LLDPE recycle will have at least one parameter distinguishing it from the second processed LLDPE recycle.

-Virgin LLDPE

In some embodiments, ziegler-Natta (ZN) catalysts are used. Such catalysts are based on group IVB transition metalsA compound and an organoaluminum compound (co-catalyst). Such transition metals include, but are not limited to, ti, zr, and Hf. Non-limiting examples of ZN catalyst systems include TiCl ₄ +Et ₃ Al and TiCl ₃ +AlEt ₂ Cl. The LLDPE homopolymers and/or copolymers have some long chain branching and 0.910g/cm ³ To 0.940g/cm ³ Density in the range.

The virgin LLDPE can be characterized as having:

-LLDPE recycle feedstock

In some embodiments, the LLDPE recycle feedstock is derived from an ethylene homopolymer, units derived from ethylene, and units derived from one or more C' s ₃ -C ₁₂ Copolymers of units of alpha-olefins, copolymers of units derived from ethylene and units derived from one or more alpha-mono-olefins. Such C ₃ -C ₁₂ Alpha-olefins include, but are not limited to, substituted or unsubstituted C ₃ To C ₁₂ Alpha olefins such as propylene, butene, pentene, hexene, heptene, octene, nonene, decene, undecene, dodecane and isomers thereof. When present, the comonomer may be present in an amount of up to 20wt%, 15wt%, 10wt% or 5 wt%. The LLDPE recycle feedstock may be derived as part of a post consumer recycled polyolefin and/or an post industrial recycled polyolefin consisting essentially of LLDPE recycle, where "essentially" means greater than or equal to 80wt%, greater than or equal to 85wt%, greater than or equal to 90wt% or greater than or equal to 95wt%, based on the total weight of the LLDPE recycle feedstock 。

ii) a melt index (2.16 kg,190 ℃) of less than or equal to 5.0g/10 min;

v) a melt elasticity ("ER") of greater than or equal to 0.5.

vi) a first VOC content;

vii) first high negativeMelt index (I) ₂₁ ，21.6kg，190℃)；

viii) first melt index ratio (MIR, I ₂₁ /I ₂ )；

x) a first overall polydispersity ratio (PDR);

xii) first intrinsic viscosity.

-Processed LLDPE recyclates

Melt extruder

The polyolefin blend components and optionally antioxidants and/or other components are fed into a third extruder or mixer wherein the blend is subjected to melt conditions. The melting conditions are carried out in the melting zone of the third extruder or mixer and are tailored to the particular polyolefin and optional additives mixture. Temperature, pressure and shear conditions sufficient to provide intimate mixing of the processed LLDPE recycle and virgin LLDPE and optional additives are conducted in a second extruder or mixer to produce a substantially homogeneous polymer blend of the processed LLDPE recycle and virgin LLDPE. In some embodiments, the melting conditions include a temperature in the melting zone in the range of 130 ℃ to 250 ℃ or 150 ℃ to 230 ℃.

Compounding extruder

Blend of processed LLDPE recycle and polyolefin blend components

In some embodiments, the blend of the processed LLDPE recycle and the polyolefin blend component, in combination or independently of the blend ratio in the preceding paragraph, comprises a bimodal polymer, wherein the processed LLDPE recycle product has a weight average molecular weight ("M") _w3 "), the polyolefin blend component has a weight average molecular weight (" M ") _w4 ""; and M is _w3 /M _w4 Less than or equal to 0.9, 0.8, 0.7, 0.6, or 0.5, or alternatively greater than or equal to 1.1, 1.25, 1.5, 1.75, or 2.0.

Certain embodiments

In some embodiments, a method for processing a Linear Low Density Polyethylene (LLDPE) recycle includes providing a LLDPE recycle feedstock, adding the LLDPE recycle to a first extruder to produce a first LLDPE recycle melt, and subjecting the first LLDPE recycle melt to visbreaking conditions to produce a second LLDPE recycle melt. The LLDPE recycle raw material comprises: at 0.910g/cm ³ To 0.940g/cm ³ A first density within a range; a first melt index (2.16 kg,190 ℃) of less than or equal to 5.0g/10 minutes; a first molecular weight distribution (M) of greater than or equal to 5.0, greater than or equal to 7.0, greater than or equal to 10.0, or greater than or equal to 15.0 _w /M _n ) The method comprises the steps of carrying out a first treatment on the surface of the A first weight average molecular weight ("M") of greater than or equal to 85,000 daltons, greater than or equal to 120,000 daltons, greater than or equal to 180,000 daltons, or greater than or equal to 200,000 daltons, and/or less than or equal to 500,000 daltons, less than or equal to 400,000 daltons, less than or equal to 350,000 daltons, or less than or equal to 250,000 daltons _w1 ""; and a first melt elasticity ("ER") of greater than or equal to 0.5.

The second LLDPE recycle melt has: a second density, wherein the ratio of the second density to the first density is greater than or equal to 1.0; a second melt index, wherein the ratio of the second melt index to the first melt index is greater than or equal to 5.0, and/or the processed LLDPE recycle has a melt index (I) greater than or equal to 5.0g/10 minutes ₂ ) The method comprises the steps of carrying out a first treatment on the surface of the A second molecular weight distribution, wherein the ratio of the second molecular weight distribution to the first molecular weight distribution is less than or equal to 0.8, and/or the molecular weight distribution of the processed LLDPE recycle is less than or equal to 5.0; second weight average molecular weight ("M) _w2 ") where M _w2 /M _w1 Less than or equal to 0.90 or less than or equal to 0.80; and a second melt elasticity, wherein the ratio of the second melt elasticity to the first melt elasticity is less than or equal to 0.50, less than or equal to 0.40, or less than or equal to 0.30 and/or the second melt elasticity is less than 0.50.

In a further embodiment, the method is further characterized by one or more of the following:

a) LLDPE recycle raw materials include post-consumer recycle waste, post-industrial recycle waste, or a combination thereof;

b) Visbreaking conditions consist of thermal visbreaking, which in some cases is carried out at a temperature greater than or equal to 300 ℃, or at a temperature ranging from 320 ℃ to 400 ℃;

c) Subjecting the first LLDPE recycle melt to a devolatilization condition to produce a second LLDPE recycle melt, wherein the LLDPE recycle feedstock has a first volatile organic compound content, the first LLDPE recycle melt has a second volatile organic compound content, and a ratio of the second volatile organic compound content to the first volatile organic compound content is less than or equal to 0.9, and in some cases, the devolatilization condition further comprises:

i) Injection and evacuation of a purge gas, and in some cases, the purge gas comprises nitrogen, carbon dioxide, water, or a combination thereof;

ii) an evacuation condition, a vacuum condition, or a combination thereof;

d) Passing the second LLDPE recycle melt through a melt filter;

e) Adding an antioxidant to the first extruder; and

f) The LLDPE recycle feed has a first high load melt index (21.6 kg,190 ℃) and the second LLDPE recycle melt has a second high load melt index and the ratio of the second high load melt index to the first high load melt index is greater than or equal to 2.0, greater than or equal to 3.0, or greater than or equal to 4.0;

g) The LLDPE recycle feedstock has a first melt index ratio (I ₂₁ /I ₂ ) The second LLDPE recycle melt has a second melt index ratio and the ratio of the second melt index ratio to the first melt index ratio is less than or equal to 0.90, less than or equal to 0.85, or less than or equal to 0.80;

h) The LLDPE recycle feed has a first long chain branching parameter (g ') in the range of from 0.85 to 1.00, from 0.90 to 0.99, or from 0.92 to 0.98, the ratio of the second LLDPE recycle and/or the second g ' to the first g ' being less than or equal to 1.0;

i) The LLDPE recycle feedstock has a first long chain branching index ("LCBI") greater than or equal to 0, and the processed LLDPE recycle has an LCBI greater than 0;

j) The LLDPE recycle feedstock has an overall polydispersity measurement ("PDR"), the second LLDPE recycle melt has a second PDR, and the ratio of the second PDR to the first PDR is less than or equal to 0.90, less than or equal to 0.80, or less than or equal to 0.70;

k) LLDPE recycle feedstock having a first complex viscosity ratioWherein the ratio of the complex viscosity ratio of the processed LLDPE recycle to the complex viscosity ratio of the LLDPE recycle feedstock is less than or equal to 0.7, less than or equal to 0.6, or less than or equal to 0.5, and/or the complex viscosity ratio of the processed LLDPE recycle is less than or equal to 3.0 or less than or equal to 2.0; and

l) the LLDPE recycle feedstock has a first intrinsic viscosity, the second LLDPE recycle melt has an intrinsic viscosity, and the ratio of the second intrinsic viscosity to the first intrinsic viscosity is less than or equal to 0.90, less than or equal to 0.80, or less than or equal to 0.70.

In some embodiments, the foregoing method further comprises forming the LLDPE recycle product by withdrawing the second LLDPE recycle melt from the first extruder to further process or pelletize the second LLDPE recycle melt.

In a further embodiment of the foregoing process, the LLDPE recycle product and the first polyolefin blend component are added to a second extruder, and compounding conditions are achieved in the second extruder to form a polyolefin product comprising a melt-blended mixture of the processed LLDPE recycle product and the first polyolefin blend component. In some embodiments, such compounding conditions include a temperature of less than or equal to 300 ℃. In some embodiments, the first polyolefin blend component comprises virgin polyolefin, polyolefin recycle feedstock, processed polyolefin recycle, or a combination thereof. In yet a further embodiment: the virgin polyolefin includes virgin LDPE, virgin LLDPE, virgin HDPE, virgin MDPE, virgin polypropylene, or a combination thereof; the polyolefin recycle material comprises LDPE recycle material, LLDPE recycle material, HDPE recycle material, MDPE recycle material, polypropylene recycle material or a combination thereof; and the processed polyolefin recycle comprises a processed LDPE recycle, a second processed LLDPE recycle, a processed HDPE recycle, a processed MDPE recycle, a processed polypropylene recycle, or a combination thereof. In some embodiments, the first polyolefin blend component comprises virgin LLDPE, LLDPE recycle feedstock, processed LLDPE recycle, or a combination thereof.

In a further embodiment of the foregoing process, the LLDPE recycle product: added in an amount ranging from 5wt.% to 90wt.%, or from 20wt.% to 60wt.%, based on the total weight of the LLDPE recycle product and the first polyolefin blend component; and/or the LLDPE recycle product has a third weight average molecular weight ("M _w3 ") the first polyolefin blend component has a fourth weight average molecular weight (" M ") _w4 ") and

M _w3 /M _w3 less than or equal to 0.8 or greater than or equal to 1.25.

In further embodiments of the foregoing process, the first polyolefin blend component is a first virgin LLDPE comprising the polymer product produced in the first polymerization unit, wherein in some cases the polymer product is subjected to a visbreaking process after polymerization, and in some embodiments the visbreaking process comprises thermal visbreaking, peroxide visbreaking, or a combination thereof.

In a further embodiment of the foregoing process, the first polyolefin blend component comprises a polyolefin powder prepared in a first polymerization unit.

In a further embodiment of the foregoing method, an antioxidant is added to the second extruder.

In a further embodiment of the foregoing method, the method further comprises: adding a second polyolefin blend component to a third extruder; achieving melt conditions in a third extruder to produce a second polyolefin blend component melt; the second polyolefin blend component melt is discharged as the first polyolefin blend component.

In a further embodiment of the foregoing process, the second polyolefin blend component comprises virgin LLDPE, a LLDPE recycle feedstock, processed LLDPE recycle, or a combination thereof.

In a further embodiment of the foregoing process, the second polyolefin blend component is subjected to a visbreaking process after polymerization, wherein in some cases the visbreaking process consists of thermal visbreaking.

In a further embodiment of the foregoing process, the second polyolefin blend component comprises polyethylene powder and/or polyethylene pellets prepared in the second polymerization unit.

In a further embodiment of the foregoing process, the first polymerization device and/or the second polymerization device each comprise more than two polymerization reactors and/or two or more polymerization zones within a polymerization reactor.

In a further embodiment of the foregoing process, the first polymerization device and/or the second polymerization device each comprises two or more gas phase fluidized bed reactors in series, two or more slurry phase reactors in series, or a gas phase fluidized bed reactor in series with a multi-zone circulating reactor.

In a further embodiment of the foregoing method, an antioxidant is added to the third extruder.

In some embodiments, a composition includes a polymer blend of a first polymer and a second polymer. The first polymer is a first processed LLDPE recycle and is present in an amount in the range of 5wt.% to 90 wt.%. The second polymer is virgin polyolefin, polyolefin recycle feedstock, processed polyolefin recycle, or a combination thereof, and is present in an amount in the range of 10wt.% to 95 wt.%. All weight percentages are based on the total weight of the first polymer and the second polymer.

In a further embodiment of the foregoing composition: the virgin polyolefin includes virgin LDPE, virgin LLDPE, virgin HDPE, virgin MDPE, virgin polypropylene, or a combination thereof; the polyolefin recycle material comprises LDPE recycle material, LLDPE recycle material, HDPE recycle material, MDPE recycle material, polypropylene recycle material or a combination thereof; and the processed polyolefin recycle comprises a processed LDPE recycle, a second processed LLDPE recycle, a processed HDPE recycle, a processed MDPE recycle, a processed polypropylene recycle, or a combination thereof.

In a further embodiment of the foregoing composition, processing means undergoing thermal visbreaking or undergoing thermal visbreaking and devolatilization.

In some embodiments, the blend includes a blend having a first I ₂ Visbroken LLDPE of (C) and having a second I ₂ A virgin LLDPE of (a), a LLDPE recycle feedstock, a processed LLDPE recycle, or a combination thereof, wherein:

(I ₂ ) _{blends of} Is the target melt index of the final blend product;

n is the number of components in the blend; and

i is the i-th component of the n-component blend.

The following examples illustrate the invention; however, those skilled in the art will recognize many variations that are within the spirit of the invention and scope of the claims. In order to facilitate a better understanding of the present invention, the following examples of preferred embodiments are given. The following examples should not be construed as limiting or restricting the scope of the invention.

Examples

The following examples are included to demonstrate preferred embodiments of the invention. It should be appreciated by those of skill in the art that the techniques disclosed in the examples which follow represent techniques discovered by the inventor to function well in the practice of the invention, and thus can be considered to constitute preferred modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.

The following examples use commercial LLDPE compositions having low melt index as a substitute for LLDPE recycle raw materials. After processing, the visbroken low melt index LLDPE (alone or blended with other components) is compared with the higher melt index virgin LLDPE, as described herein.

Test method

Density was determined according to ASTM D-4703 and ASTM D-1505/ISO-1183.

High load melt index (' I) ₂₁ ") was determined by ASTMD-1238-F (190 ℃ C./21.6 kg).

Shear rheology measurements were performed according to ASTM4440-95a, which characterizes dynamic viscoelasticity properties (storage modulus G', loss modulus G "and complex viscosity η ^* As a function of the oscillation frequency ω). Rheometry was performed using a rotary rheometer (TA Instruments). A 25mm parallel plate clamp was used. The samples were compression molded into discs (about 29mm diameter and about 1.3mm thickness) using a hot press at 190 ℃. The oscillation frequency sweep experiment (398.1 rad/s to 0.0251 rad/s) was performed at 190 ℃. The applied strain amplitude was about 10%, and the operating gap was set to 1mm. A nitrogen flow is applied in the sample chamber to minimize thermal oxidation during measurement.

Melt elasticity ("ER") is determined as described in New measurement method for polydispersity of Polymer melt rheology data (New Measures of Polydispersity from Rheological Data on Polymer Melts) by R.Shroff and H.Mavridis, J.applied Polymer Science, 57 (1995) 1605. See also U.S. patent nos. 7,238,754, 6,171,993 and 5,534,472 (column 10, lines 20-30), the teachings of which are incorporated herein by reference. Thus, the storage modulus (G ') and loss modulus (G') were measured. Nine lowest frequency points (5 points per frequency decade) were used and the linear equation was fitted to log 'versus log' by least squares regression. ER is then calculated according to the following equation:

ER＝(1.781×10 ^-3 )×G'

Wherein G "=5,000 dyn/cm ² . ER is calculated using the same procedure and equations for both linear and long chain branched polyolefins.

PDR or"Total polydispersity measurement" is determined as discussed in New measurement of polydispersity of Polymer melt rheology data by R.Shroff and H.Mavridis, J.App.Polymer science 57 (1995) 1605, page 1619, equation 27, where G _ref,1 ＝1.95*10 ⁴ dyn/cm ² And log of ₁₀ (G* _ref,3 /G* _ref,1 ) =2. The PDR is calculated using the same procedure and equations for both linear and long chain branched polyolefins.

At a frequency of 0.1 rad/sec and at a frequency of 100 rad/secComplex viscosity->Is used as an additional measure of shear sensitivity +.>And thus serves as an additional measure of the rheological breadth or polydispersity of the polymer melt.

Melt index (' I) ₂ ") was determined by ASTM D-1238-E (190 ℃ C./2.16 kg).

Molecular weight distribution ("MWD") and molecular weight average (number average molecular weight M _n、 Weight average molecular weight M _w And a z-average molecular weight M _z ) High temperature polymer carbon gel permeation chromatography ("GPC") (also known as size exclusion chromatography ("SEC")) was used to determine, and was equipped with a filter-based infrared detector IR5, a four-capillary differential bridge viscometer, and a Wyatt 18 angle light scattering detector. M is M _n 、M _w 、M _z MWD and Short Chain Branching (SCB) spectra were reported using an IR detector, while long chain branching parameters g' were determined using a combination of viscometer and IR detector at 145 ℃. Based on hydrodynamic size in 1,2, 4-Trichlorobenzene (TCB), polymer fractionation was performed at 145 ℃ using three Agilent (Agilent) PLgel oxides GPC columns with 300ppm antioxidant Butylated Hydroxytoluene (BHT) as mobile phase. Weigh 16 in a 10mL vialmg polymer and sealed for GPC measurement. In an Agilent autosampler, the dissolution process was completed automatically (in 8ml TCB) with continuous shaking for 1 hour at 160 ℃. During the dissolution process, 20 μl of heptane was also injected into the vial as a flow marker. After the dissolution process, 200 μl of the solution was injected into the GPC column. GPC columns were calibrated based on twelve monodisperse Polystyrene (PS) standards (supplied by PSS) of 578 g/mol to 3,510,000 g/mol. Comonomer composition (or SCB profile) is reported based on different calibration profiles obtained using a series of relatively narrow polyethylenes (polyethylene with 1-hexene and 1-octene comonomers provided by the polymeric char and polyethylene with 1-butene synthesized internally) with known CH ₃ Total carbon number/1000, which is determined by established solution NMR techniques. Data were analyzed using GPC one software. The long chain branching parameter g' is determined by the following equation:

g'＝[η]/[η] _lin

where [ eta ] is the average intrinsic viscosity of the polymer, which is derived by summing the slices over the GPC profile, as follows:

wherein c _i Is the concentration of a particular slice obtained from the IR detector, and [. Eta. ]] _i Is the intrinsic viscosity of the slice measured from the viscometer detector. [ eta ]] _lin Using the mark-houwink equation for linear high density polyethyleneObtained from IR detector, where M _i Is for the reference linear polyethylene, K and α are the mark-houwink constants for the linear polymer, which are k= 0.000374, α= 0.7265 for the linear polyethylene and k=0.00041, α= 0.6570 for the linear polypropylene.

Volatile organic compounds ("VOCs") are separated by pyrolysis-gas chromatography/mass spectrometry ("P-GC/MS") in parts per billion (ppb), millionsFraction (ppm) or sum micrograms/cubic meter (μg/m) ³ ) And (5) measuring.

Determination of zero shear viscosity η using a Sabia equation fit of dynamic complex viscosity to radian frequency ₀ The disclosures of which are incorporated herein by reference in their entirety, as described in Shroff and Mavridis, (1999) long chain branching index of substantially linear polyethylenes (A Long Chain Branching Index for Essentially Linear Polyethylenes), macromolecules (32, 8454-8464, focusing on appendix B).

LCBI is determined using equation 13:

equation 13 and its use are described in Shroff and Mavridis, (1999) long chain branching index of substantially linear polyethylene, macromolecules, 32, 8454-8464, the disclosure of which is incorporated herein by reference in its entirety.

By the method of Janzen and Colby (J. Janzen and R.H.Colby, "diagnosis of long chain branching in polyethylene (diagnosis Long-chain branching in polyethylenes)," journal of molecular Structure (Journal of Molecular Structure), "volumes 485 to 486, 10, 1999, pages 569 to 583), the long chain branching frequency is determined using equations (2 to 3) and constants of Table 2 in the above references, characterized by the long chain branching ratio per million carbon atoms, or LCB/10 ⁶ C. In particular, the method comprises the steps of,the zero shear viscosity below is determined by extrapolating the complex viscosity data via the Sabia equation, as described separately. The weight average molecular weight Mw is determined by GPC. Using these two parameters and the methods of Janzen and Colby, the long chain branching frequency LCB/10 ⁶ C can be determined numerically so that all 3 parameters (η ₀ 、M _w And LCB/10 ⁶ C) Equations (2 to 3) in the above references are satisfied. The method of Janzen and Colby predicts zero shear viscosity of the material versus a fully linear polymer (LCB/10) with the same average molecular weight ⁶ C=0) ratio η of zero shear viscosity ₀ /η _{0, linearity} In LCB/10 ⁶ Exhibits a maximum value at a certain value of C and thus for eta ₀ /η _{0, linearity} There are two LCB/10's per value ⁶ The level or value of C may reach such a ratio. LCB/10 for the purposes of this calculation ⁶ The lowest value of C is always in a given ratio _η 0/η _{0, linearity} And (5) selecting.

Raw materials

The raw materials used herein are shown in table 1 below.

TABLE 1

*190℃/2.16 kg

* All materials were purchased from liandebarcel industries (LyondellBasell Industries NV)

Examples 1 to 3

Examples 1 to 3 in table 2 show the visbreaking results of the LLDPE resins. P1 is believed to clearly represent the LLDPE recycle feedstock. P1 (LLDPE recycle raw material substitute) had a weight of 0.921g/cm prior to processing ³ And a melt index I of 2.1g/10 min ₂ . The results of example 1 in table 2 show many other properties of P1.

Examples 2 and 3 were prepared by visbreaking part P1. Visbreaking was performed by feeding P1 into Werner and pfleiderer zsk40 twin screw extruders at a feed rate of 50 lbs/hr, screw speed of 600rpm and target temperature profile of 200/250/325/325/325/325/325/325/325 deg.c (from the feed inlet to the die). The extrudate is crushed into pellets. In examples 2 and 3, a different screw design was used, resulting in an increase in the energy input of the polymer in the extruder in example 3 compared to example 2. In Table 2, visbroken P1 of example 2 using the first extruder screw design is labeled P1-vb1, while visbroken P1 of example 3 using the second extruder screw design is labeled P1-vb2.

Example 2 it is shown that,melt index I of P1 ₂ The improvement by visbreaking was 6.4 times, whereas the density was only nominally increased. Example 3 shows the melt index I of P1 ₂ The improvement by visbreaking was 7.2-fold. Melt index I in examples 2 and 3 ₂ The difference in (a) was attributed to the specific energy ("SPE") input of the polymer being 0.498kW.hr/kg and 0.540kW.hr/kg, respectively.

Examples show high load melt index I for P1 ₂₁ Is improved by a factor of 4.9 by visbreaking and the melt index ratio (I ₂₁ /I ₂ ) From 29 to 22. In both examples 2 and 3 the melt elasticity ("ER") was reduced by about half. The overall polydispersity measure ("PDR") of examples 2 and 3 is reduced by about one third.

In examples 2 and 3, complex viscosity compared to P1And->All reduced by several orders of magnitude and complex viscosity ratio +.>About half a decrease. In examples 2 and 3, the intrinsic viscosity [ eta ]]About one third less.

In examples 2 and 3, the number average molecular weight (M compared with P1 _n ) Reduced by 19% and 27%, respectively, weight average molecular weight (M _w ) Reduced by 42% and 43%, Z-average molecular weight (M _z ) The reduction is 53% and 54%. In examples 2 and 3, the molecular weight distribution (M _w /M _n ) Respectively 28% and 21%, while the molecular weight ratio (M _z /M _w ) Reduced by 19% and 20%, respectively.

TABLE 2

vb=visbreaking

Dynamic oscillation data generated based on sample analysis of P1, P1-vb1 and P1-vb2 are shown in Table 3 below . The data in Table 3 show that for all P1, P1-vb1 and P1-vb2, the complex viscosity decreases with increasing frequency. Table 3 further shows that visbreaking P1 results in lower complex viscosities (. Eta.) of P1-vb1 and P1-vb2 for all tested frequency values ^* ). In addition, the complex viscosity difference between P1 and P1-vb2 decreases with increasing frequency. Applicants believe that this suggests, without wishing to be bound by any particular theory, that visbreaking has a greater effect on the higher molecular weight chains in LLDPE, i.e., more chain scission, and further that the MWD of P1-vb1 (M _w /M _n ) Narrower. Fig. 4 is a comparison of the curves generated by the data in table 3 versus examples 1 to 3. Superimposed graphs show the complex viscosity in poise (eta ^* ) As a function of the logarithm of the oscillation frequency in radians per second.

TABLE 3 Table 3

Fig. 5 is a comparison of the molecular weight curves generated in examples 1 to 3. The superimposed graph shows the molecular weight reduction and narrowing of the molecular weight distribution achieved by visbreaking.

For brevity, only certain ranges are explicitly disclosed herein. However, in addition to the recited ranges, any lower limit may be combined with any upper limit to list the ranges not explicitly recited, and ranges from any lower limit may be combined with any other lower limit to list the ranges not explicitly recited, as well as ranges from any upper limit may be combined with any other upper limit to list the ranges not explicitly recited. In addition, each point or individual value between its endpoints is included within a range even though not explicitly recited. Thus, each point or individual value may be combined as its own lower or upper limit with any other point or individual value or any other lower or upper limit to list ranges not explicitly recited.

Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Furthermore, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, membrane structure, composition of layers, means, methods and/or steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, membrane structures, compositions of layers, means, methods, and/or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, film structures, compositions of matter, means, methods, and/or steps.

Claims

1. A method for processing a Linear Low Density Polyethylene (LLDPE) recycle, comprising:

a. providing an LLDPE recycle feedstock having:

i) At 0.910g/cm ³ To 0.940g/cm ³ A first density within a range;

ii) a first melt index (I) of less than or equal to 5.0g/10 min ₂ )；

iii) A first molecular weight distribution (M) greater than 5.0 _w /M _n )；

iv) a first weight average molecular weight ("M") greater than or equal to 85,000 daltons _w1 ""; and

v) a first melt elasticity ("ER") greater than or equal to 0.5;

b. adding the LLDPE recycle to a first extruder to produce a first LLDPE recycle melt; and

c. subjecting the first LLDPE recycle melt to visbreaking conditions to produce a second LLDPE recycle melt having:

i) A second density, wherein a ratio of the second density to the first density is greater than or equal to 1.0;

ii) a second melt index, wherein the ratio of the second melt index to the first melt index is greater than or equal to 5.0;

iii) A second molecular weight distribution, wherein the ratio of the second molecular weight distribution to the first molecular weight distribution is less than or equal to 0.8;

iv) a second weight average molecular weight ("M _w2 ") where M _w2 /M _w1 Less than or equal to 0.90; and

v) a second melt elasticity, wherein the ratio of the second melt elasticity to the first melt elasticity is less than or equal to 0.50 and/or the second melt elasticity is less than 0.5.

2. The method of claim 1, wherein the LLDPE recycle feedstock comprises post-consumer recycle waste, post-industrial recycle waste, or a combination thereof.

3. The method of claim 1, wherein the visbreaking conditions consist of thermal visbreaking.

4. A process according to claim 3, wherein thermal visbreaking is carried out at a temperature greater than or equal to 300 ℃.

5. The method of claim 1, further comprising further subjecting the first LLDPE recycle melt to devolatilization conditions to produce the second LLDPE recycle melt, wherein:

the LLDPE recycle feedstock has a first volatile organic compound content;

the first LLDPE recycle melt having a second volatile organic compound content; and

the ratio of the second volatile organic compound content to the first volatile organic compound content is less than or equal to 0.9.

6. The method of claim 5, wherein the devolatilization conditions comprise injection and evacuation of a purge gas.

7. The method of claim 1, wherein the method is characterized by one or more of the following:

i) The LLDPE recycle feedstock has a first high load melt index (I ₂₁ ) The second LLDPE recycle melt has a second high load melt index and the ratio of the second high load melt index to the first high load melt index is greater than or equal to 2.0;

ii) the LLDPE recycle feedstock has a first melt index ratio (I) ₂₁ /I ₂ ) The second LLDPE recycle melt has a second melt index ratio and the ratio of the second melt index ratio to the first melt index ratio is less than or equal to 0.90;

iii) The LLDPE recycle feedstock has a first long chain branching parameter (g ') in the range of 0.85 to 1.00, the second LLDPE recycle melt has a second g', and the ratio of the second g 'to the first g' is less than or equal to 1.0;

iv) the LLDPE recycle feedstock has a first long chain branching index ("LCBI") less than or equal to 0 and the second LLDPE recycle melt has a second LCBI ") greater than 0;

v) the LLDPE recycle feedstock has an overall polydispersity measurement ("PDR"), the second LLDPE recycle melt has a second PDR, and the ratio of the second PDR to the first PDR is less than or equal to 0.90;

vi) the LLDPE recycle feedstock has a first complex viscosity ratio, the second LLDPE recycle melt has a second complex viscosity ratio, and the ratio of the second complex viscosity ratio to the first complex viscosity ratio is less than or equal to 0.70, and/or the second complex viscosity ratio is less than or equal to 3.0; and

vii) the LLDPE recycle feedstock has a first intrinsic viscosity, the second LLDPE recycle melt has a second intrinsic viscosity, and the ratio of the second intrinsic viscosity to the first intrinsic viscosity is less than or equal to 0.90.

8. The method of claim 1, wherein the LLDPE recycle product is formed by withdrawing the second LLDPE recycle melt from the first extruder for further processing or pelletizing the second LLDPE recycle melt.

9. The method of claim 8, further comprising:

adding the LLDPE recycle product and a first polyolefin blend component to a second extruder; and

compounding conditions are achieved in the second extruder to form a polyolefin product comprising a melt blended mixture of the processed LLDPE recycle product and the first polyolefin blend component.

10. The method of claim 9, wherein the first polyolefin blend component comprises virgin polyolefin, polyolefin recycle feedstock, processed polyolefin recycle, or a combination thereof.

11. The composition of claim 10, wherein:

a. the virgin polyolefin comprises virgin LDPE, virgin LLDPE, virgin HDPE, virgin MDPE, virgin polypropylene, or a combination thereof;

b. The polyolefin recycle raw material comprises LDPE recycle raw material, LLDPE recycle raw material, HDPE recycle raw material, MDPE recycle raw material, polypropylene recycle raw material or a combination thereof; and

c. the processed polyolefin recycle comprises a processed LDPE recycle, a second processed LLDPE recycle, a processed HDPE recycle, a processed MDPE recycle, a processed polypropylene recycle, or a combination thereof.

12. The method of claim 11, wherein the first polyolefin blend component comprises virgin LLDPE, a LLDPE recycle feedstock, a processed LLDPE recycle, or a combination thereof.

13. The method of claim 9, wherein the LLDPE recycle product is added in an amount ranging from 5wt.% to 90wt.% based on the total weight of the LLDPE recycle product and the first polyolefin blend component.

14. The method of claim 9, wherein the compounding conditions comprise a temperature of less than or equal to 300 ℃.

15. The method of claim 9, further comprising:

adding a second polyolefin blend component to a third extruder;

achieving melt conditions in the third extruder to produce a second polyolefin blend component melt; and

Withdrawing the second polyolefin blend component melt as the first polyolefin blend component.

16. The method of claim 15, wherein the second blend component comprises virgin LLDPE, a LLDPE recycle feedstock, a processed LLDPE recycle, or a combination thereof.

17. A composition comprising a polymer blend of:

a. a first polymer, wherein the first polymer:

i) Is a first processed LLDPE recycle; and is also provided with

ii) is present in an amount ranging from 5wt.% to 90 wt.%;

and

b. A second polymer, wherein the second polymer:

i) Is virgin polyolefin, polyolefin recycle feedstock, processed polyolefin recycle, or a combination thereof; and is also provided with

ii) is present in an amount ranging from 10wt.% to 95 wt.%;

wherein all weight percentages are based on the total weight of the first polymer and the second polymer.

18. The composition of claim 17, wherein:

19. The composition of claim 17, wherein processing means undergoing thermal visbreaking and optionally undergoing devolatilization.

20. A blend, comprising:

visbroken LLDPE having a first I ₂ The method comprises the steps of carrying out a first treatment on the surface of the And

having a second I ₂ Raw LLDPE, LLDPE recycle feedstock, processed LLDPE recycle, or a combination thereof;

wherein:

(I ₂ ) _{blends of} Is the target melt index of the final blend product;

n is the number of components in the blend; and

i is the i-th component of the n-component blend.