WO2024172898A1 - Polyethylene compositions containing recycled material - Google Patents

Abstract

A high density polyethylene (HDPE) composition comprises: a) a recycled HDPE resin having density from 0.94 g/cc to 0.97 g/cc, melt index (MIr) from 0.5 to 1 dg/min., and molecular weight distribution (Mw/Mn) from 8 to 15; and b) a virgin HDPE resin having a density from 0.940 g/cc to 0.970 g/cc, a melt index (MIv) from 2/MIr dg/min.to 32/MIr dg/min, and molecular weight distribution (Mw/Mn) from 2 to 5, wherein the weight percentage of virgin HDPE resin (Wv), based solely on the combined weight of virgin HDPE resin and recycled HDPE resin, meets the equations: Wv ? [ (0.66 dg/min - MIr(-0.257)) / (MIv(-0.257) - MIr(-0.257))] x 100/dg/min, and Wv ? [1-(0.2125MIr+ 0.0025MIv)] x 100/dg/min.

Description

POLYETHYLENE COMPOSITIONS CONTAINING RECYCLED MATERIAL FIELD [0001] The present invention relates to the field of polyethylene compositions that contain recycled material. BACKGROUND [0002] HDPE resin and polymer blends that contain HDPE resin are commonly used in packaging, such as bottles, jars and their closures. The packaging can be molded using known techniques, such as injection molding, compression molding and blow molding. Injection molding is commonly used for making complex shaped articles, such as caps, closures, threaded items and hinged items. [0003] Molding processes require the HDPE resin to provide an appropriate balance of easy processability and physical properties. For injection molding processes, the HDPE resin desirably has low melt viscosity and high shear thinning ratio so that it flows easily through the mold, and a low shrinkage anisotropy so that it minimizes deforming as it cools. Further, the HDPE resin desirably has good toughness (high breaking strain) and high strength (high breaking stress), so that it forms durable molded articles. [0004] Recycled HDPE resins are frequently blended with freshly made (“virgin”) HDPE in order to provide a blend that can meet specifications needed for commercial use. Such blends desirably contain as much recycled plastic as practical, in order to maximize the amount of recycled plastic used and minimize the amount of virgin plastic needed. It is desirable to identify blends of virgin HDPE resins with recycled HDPE resins that have a good balance of processability and physical properties that can be useful in injection molding or injection blow molding processes. SUMMARY [0005] Disclosed herein is a high density polyethylene composition. In a first aspect, the high density polyethylene (HDPE) composition comprising: a) a recycled HDPE resin having density from 0.940 g/cc to 0.970 g/cc, a melt index (MI_r) from 0.50 to 1.00 dg/min, and a molecular weight distribution (M_w/M_n) from 8 to 15; and b) a virgin HDPE resin having a density from 0.940 g/cc to 0.970 g/cc, a melt index (MI_v) from 2/MI_r dg/min to 32/MI_r dg/min, and a molecular weight distribution (M_w/M_n) from 2 to 5, wherein the weight percent of the virgin HDPE resin (W_v), based solely on the combined weight of virgin HDPE resin and recycled HDPE resin, meets the following equations: W_v ≥ [ (0.66 dg/min - MI_r ^(-0.257)) / (MI_v ^(-0.257) - MI_r ^(-0.257))] x 100/dg/min, and W_v ≤ [1-(0.2125MI_r+ 0.0025MI_v)] x 100/dg/min; and wherein the MI_r and MI_v are (I₂) and determined according to ASTM D1238 at 190°C, 2.16 kg. [0006] Also disclosed herein is a process for making a molded article. In this second aspect of the invention, the process to make a molded article comprising the steps of: (1) injecting a high density composition according to the embodiments disclosed herein into a mold; (2) cooling the high density polyethylene composition in the mold until solidified to form the molded article. [0007] Also disclosed herein is a molded article. In this third aspect of the invention, a molded article comprises the HDPE composition in the first aspect of the invention. [0008] Also disclosed herein is a process for forming a high density polyethylene composition. In this fourth aspect of the invention, the process comprises (a) providing a recycled HDPE resin having a density from 0.940 g/cc to 0.970 g/cc, a melt index (MIr) from 0.50 to 1.00 dg/min, and a molecular weight distribution (Mw/Mn) from 8 to 15; (b) a virgin HDPE resin having a density from 0.940 g/cc to 0.970 g/cc, a melt index (MIv) from 2/MIr dg/min to 32/MIr dg/min, and a molecular weight distribution (Mw/Mn) from 2 to 5; (c) melt blending a weight percent of the virgin HDPE resin (Wv) with a weight percent of the recycled HDPE resin (Wr), based solely on combined weight of the virgin HDPE resin and the recycled HDPE resin, wherein Wr = 100 - Wv, and Wv is calculated according to the following equations: Wv ≥ [ (0.66 dg/min - MIr^(-0.257)) / (MIv^(-0.257) - MIr^(-0.257))] x 100 dg/min; and Wv ≤ [1 - (0.2125MIr+ 0.0025MIv)] x 100 dg/min; and wherein the MI_r and MI_v are (I₂) and determined according to ASTM D1238 at 190°C, 2.16 kg. [0009] In some aspects, the HDPE compositions of this invention can have low melt index and/or high shear thinning, so that they are easy to process, and can also provide molded articles that have a good balance of toughness and strength. The composition can provide these properties even with relatively high proportions of recycled HDPE resin that is suitable for food contact. DETAILED DESCRIPTION [0010] The term “polyethylene” refers to polymers comprising a majority amount (>50 mol %) of units which have been derived from ethylene monomer. This includes polyethylene homopolymers or copolymers (meaning units derived from two or more comonomers). HDPE Resin [0011] This invention uses high density polyethylene (HDPE) resin. HDPE resin is a polyethylene that contains repeating units derived from ethylene, optionally with repeating units derived from one or more comonomers, and that has a density from 0.935 g/cc to 0.980 g/cc. [0012] In some embodiments, the HDPE resin is a homopolymer. In some embodiments, the HDPE resin is a copolymer in which some repeating units are derived from unsaturated comonomers other than ethylene. [0013] Examples of suitable comonomers used to make HDPE resin may include alpha-olefins. Suitable alpha-olefins may include those containing from 3 to 20 carbon atoms (C3-C20). For example, the alpha-olefin may be a C4-C20 alpha-olefin, a C4-C12 alpha-olefin, a C3–C10 alpha-olefin, a C3–C8 alpha- olefin, a C₄-C₈ alpha-olefin, or a C₆-C₈ alpha-olefin. In some embodiments, the alpha-olefin is selected from the group consisting of propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene and 1-decene. In other embodiments, the alpha-olefin is selected from the group consisting of propylene, 1-butene, 1-hexene, and 1-octene. In further embodiments, the alpha-olefin is selected from the group consisting of 1-hexene and 1-octene. [0014] In some embodiments, an HDPE copolymer comprises at least 95 weight percent repeating units derived from ethylene, or at least 96 weight percent or at least 97 weight percent or at least 98 weight percent or at least 99 weight percent or at least 99.5 weight percent, with the remaining repeating units derived from unsaturated comonomers. In some embodiments, an HDPE copolymer comprises at least 4 weight percent repeating units derived from comonomers, or at least 3 weight percent or at least 2 weight percent or at least 1 weight percent or at least 0.5 weight percent, with the remaining repeating units derived from ethylene monomer. It is well known how to select comonomers and comonomer content to obtain the desired molecular weight and other properties for an HDPE copolymer. Recycled HDPE resin [0015] The HDPE composition of the present invention comprises a recycled HDPE resin. [0016] In some embodiments, the recycled HDPE resin is pre-consumer/post-industrial recycled polyethylene. The terms “pre-consumer recycled HDPE resin” and “post-industrial recycled HDPE resin” refer to HDPE polymers and blends recovered from pre-consumer material, as defined by ISO-14021, such as scraps and waste from HDPE manufacturing facilities or from HDPE fabricators. The term pre-consumer recycled HDPE resin thus includes blends of HDPE resin (optionally with other polymers) recovered from materials diverted to the waste stream during a manufacturing process. The term “recycled HDPE resin,” as used herein, refers to pre-consumer recycled HDPE resins and post-industrial recycled HDPE resin. [0017] In some embodiments, the recycled HDPE resin is post-consumer recycled (PCR) HDPE resin. The term “post-consumer recycled” (or “PCR”) HDPE resin refers to HDPE resins and blends that were previously used in a consumer application such as packaging and were recycled after their use was completed. PCR polyethylene is typically collected from recycling programs and recycling plants. Sources of PCR HDPE resin can include, for example, bottle caps and closures, milk, water or orange juice containers, detergent bottles, office automation equipment (printers, computers, copiers, etc.), white goods (refrigerators, washing machines, etc.), consumer electronics (televisions, video cassette recorders, stereos, etc.), automotive shredder residue (the mixed materials remaining after most of the metals have been sorted from shredded automobiles and other metal-rich products “shredded” by metal recyclers), packaging waste, household waste, rotomolded parts (kayaks/coolers), building waste and industrial molding and extrusion scrap. [0018] The physical, chemical, and flow properties of recycled HDPE resins differ when compared to virgin HDPE resin. • Virgin HDPE resin frequently has tight specifications for density, melt index, narrow molecular weight distribution. On the other hand, recycled HDPE resin may contain a blend of various HDPE resins with different density, melt index, and molecular weights, coming from a variety of different applications. • Virgin HDPE generally has essentially no contaminants. Recycled HDPE resin may contain contaminants from its original use, such as residue such as paper, adhesive, ink, nylon, food residue, soap and detergent residue and other polymers such as linear low density polyethylene, polypropylene, ethylene vinyl alcohol and polyethylene terephthalate (PET). • Virgin HDPE has little previous heat exposure. Recycled HDPE has been previously extruded or molded, potentially more than once. This heat history affects molecular structure of the polymers. [0019] The recycled HDPE resin in the present invention has a density from 0.940 g/cc to 0.970 g/cc. All individual values and subranges from 0.940 g/cc to 0.970 g/cc are included and disclosed herein. In some embodiments, the recycled HDPE resin has a density of at least 0.945 g/cc or at least 0.950 g/cc or at least 0.952 g/cc or at least 0.954 g/cc or at least 0.956 g/cc or at least 0.957 g/cc or at least 0.958 g/cc. In some embodiments, the recycled HDPE resin has a density of at most 0.968 g/cc or at most 0.966 g/cc or at most 0.965 g/cc or at most 0.963 g/cc or at most 0.961 g/cc. [0020] The recycled HDPE resin has a melt index (I2) of from 0.50 dg/min to 1.00 dg/min. This melt index is abbreviated MI_r in this application. All individual values and subranges from 0.50 dg/min to 1.00 dg/min are included and disclosed herein. In some embodiments, the melt index (I₂) of the recycled HDPE resin (MIr) is at least 0.52 dg/min or at least 0.54 dg/min or at least 0.56 dg/min or at least 0.58 dg/min or at least 0.60 dg/min or at least 0.62 dg/min or at least 0.65 dg/min. In some embodiments, the melt index (I2) of the recycled HDPE resin (MIr) is at most 0.90 dg/min or at most 0.85 dg/min or at most 0.80 dg/min or at most 0.75 dg/min or at most 0.72 dg/min or at most 0.70 dg/min. [0021] In some embodiments, the recycled HDPE resin has a melt flow ratio (I21/I2) of at least 60 or at least 70 or at least 80 or at least 90. In some embodiments, the melt flow ratio (I21/I2) of the recycled HDPE resin is at most 140 or at most 130 or at most 120 or at most 110 or at most 100. [0022] The recycled HDPE resin has a molecular weight distribution (Mw/Mn) of from 8 to 15. In some embodiments, the molecular weight distribution (Mw/Mn) of the recycled HDPE resin is at least 8.5 or at least 9.0 or at least 9.5 or at least 10 or at least 10.5. In some embodiments, the molecular weight distribution (Mw/Mn) of the recycled HDPE resin is at most 13 or at most 11 or at most 10 or at most 9 or at most 8.5. [0023] In some embodiments, the recycled HDPE resin has a number average molecular weight (Mn) of at least 13,000 Dalton (Da) or at least 14,000 Da or at least 15,000 Da. In some embodiments, the number average molecular weight (Mn) of the recycled HDPE resin is at most 23000 Da or at most 22,000 Da or at most 21,000 Da or at most 20,000 Da. [0024] In some embodiments, the recycled HDPE resin has a weight average molecular weight (Mw) of at least 100,000 Da or at least 105,000 Da or at least 110,000 Da. In some embodiments, the weight average molecular weight (Mw) of the recycled HDPE resin is at most 150,000 Da or at most 145,000 Da or at most 140,000 Da or at most 135,000 Da. [0025] In some embodiments, the recycled HDPE resin has a breaking strain of at least 100 percent or at least 150 percent or at least 180 percent or at least 190 percent. In some embodiments, the breaking strain of the recycled HDPE resin is at most 300 percent or at most 250 percent or at most 225 percent or at most 210 percent. [0026] In some embodiments, the recycled HDPE resin has a flexural modulus of at least 80 ksi or at least 90 ksi or at least 100 ksi. In some embodiments, the flexural modulus of the recycled HDPE resin is at most 180 ksi or at most 160 ksi or at most 150 ksi or at most 140 ksi or at most 130 ksi or at most 120 ksi. (1 ksi = 1000 psi.) [0027] Recycled HDPE resin may have a higher gel content than virgin HDPE resin, due to the more extensive heat history for the recycled HDPE resin. For example, when measured according to the Test Methods below, the virgin HDPE resin can have a total gel count in the 200 to 800 micron size range of less than 500 or less than 400, whereas in some embodiments, the recycled HDPE resin may have a total gel count in the 200 to 800 micron size range that is more than 500 or more than 1000 or more than 2000 or more than 5000. High gel counts may not be desirable, but may be unavoidable in some recycled HDPE resins. [0028] Recycled HDPE resin may have higher ash content than virgin HDPE resin due to the more extensive heat history for the recycled HDPE resin. For example, when measured according to the Test Methods below, the virgin HDPE resin may have an ash content of less than 0.05 weight percent, whereas in some embodiments, the recycled HDPE resin may have an ash content of more than 0.05 weight percent or at least 0.08 weight percent or at least 0.10 weight percent or at least 0.12 weight percent. Higher ash content may not be desirable, but may be unavoidable in some recycled HDPE resins. [0029] Recycled HDPE resin may have lower reflectance (L*) and higher yellowness index (YI) than virgin HDPE resin. For example, when measured according to the Test Methods below, the virgin HDPE resin can have a reflectance (L*) of more than 85 percent, whereas in some embodiments, the recycled HDPE resin has a reflectance (L*) of less than 85 percent or less than 80 percent or less than 78 percent. Moreover, the virgin HDPE resin may have a Yellowness Index of less than 5 or less than 3 or less than 1, whereas in some embodiments, the recycled HDPE resin has a Yellowness Index of more than 5 or at least 8 or at least 10 or at least 12. Low reflectance and high yellowness may not be desirable, but may be unavoidable in some recycled HDPE resins. [0030] Suitable recycled HDPE resins are commercially available, such as under the name Ecoprime from Envision Plastics. An exemplary recycled HDPE resin has the following properties: Melt Index 0.50 dg/min to 0.85 dg/min. D i 0958 / 0965 /

[003 ] Other recycled HDPE resins can be prepared by know processes such as: (1) separating HDPE materials having desired properties from a recycle waste stream; (2) washing the separated HDPE materials; and (3) grinding the separated HDPE materials. An example of such a process is described in European Patent 2697025 B1. Virgin HDPE Resin [0032] The HDPE composition of the present invention also comprises a virgin HDPE resin. The term “virgin HDPE resin” refers to HDPE resin that has not been previously recycled or commercially used, for example, in a consumer application. The virgin HDPE resin has • a density from 0.940 g/cc to 0.970 g/cc, • a melt index (MIv) from 2/MIr dg/min to 32/MIr dg/min, wherein MIr is the melt index of the recycled HDPE resin, and • a molecular weight distribution (M_w/M_n) from 2 to 5. [0033] The virgin HDPE resin has a density from 0.940 g/cc to 0.970 g/cc. In some embodiments, the density of the virgin HDPE resin is at least 0.945 g/cc or at least 0.950 g/cc or at least 0.955 g/cc or at least 0.957 g/cc or at least 0.959 g/cc or at least 0.960 g/cc. In some embodiments, the density of the virgin HDPE resin is at most 0.965 g/cc or at most 0.963 g/cc or at most 0.962 g/cc. [0034] The virgin HDPE resin has a melt index (MIv) of from 2/MIr dg/min.to 32/MIr dg/min, wherein MI_r is the melt index of the recycled HDPE resin and the melt index is determined according to ASTM D1238 at 190°C, 2.16 kg. In some embodiments, the virgin HDPE resin (MIv) has a melt index of at least 2.25/MIr dg/min. or at least 2.50/MIr dg/min. or at least 2.75/MIr dg/min. or at least 3.00/MIr dg/min. or at least 3.25/MIr dg/min. or at least 5.00/MIr dg/min. or at least 10.0/MIr dg/min. In some embodiments, the melt index of the virgin HDPE resin (MIv) is at most 30/MIr dg/min. or at most 25/MIr dg/min. or at most 22/MIr dg/min. or at most 20/MIr dg/min. or at most 18/MIr dg/min. or at most 15/MIr dg/min. [0035] In some embodiments, the melt index of the virgin HDPE resin (MIv) is at least 2 dg/min or at least 3 dg/min or at least 4 dg/min or at least 4.5 dg/min or at least 5 dg/min or at least 5 dg/min or at least 10 dg/min or at least 12 dg/min or at least 18 dg/min or at least 20 dg/min. In some embodiments, the melt index of the virgin HDPE resin (MIv) is at most 64 dg/min or at most 60 dg/min or at most 50 dg/min or at most 41 dg/min or at most 38 dg/min or at most 35 dg/min or at most 32 dg/min or at most 30 dg/min. [0036] In some embodiments, the virgin HDPE resin has a melt flow ratio (I21/I2) of at least 8 or at least 10 or at least 15 or at least 20. In some embodiments, the melt flow ratio (I21/I2) of the virgin HDPE resin is at most 65 or at most 55 or at most 45 or at most 35 or at most 30. _[0037] The virgin HDPE resin has a molecular weight distribution (M_w/M_n) of from 2 to 5. In some embodiments, the virgin HDPE resin has molecular weight distribution (Mw/Mn) of is at least 2.5 or at least 3.0 or at least 3.5. In some embodiments, the molecular weight distribution (Mw/Mn) of the virgin HDPE resin is at most 4.8 or at most 4.7or at most 4.6. [0038] In some embodiments, the virgin HDPE resin has a number average molecular weight (Mn) of at least 8000 Da or at least 8500 Da or at least 9000 Da. In some embodiments, the number average molecular weight (Mn) of the virgin HDPE resin is at most 20000 Da or at most 19000 Da or at most 18000 Da or at most 17000 Da. [0039] In some embodiments, the virgin HDPE resin has a weight average molecular weight (Mw) of at least 35000 Da or at least 36000 Da or at least 37000 Da. In some embodiments, the weight average molecular weight (Mw) of the virgin HDPE resin is at most 75000 Da or at most 74000 Da or at most 73000 Da or at most 72000 Da. [0040] In some embodiments, the virgin HDPE resin has a unimodal molecular weight distribution. A unimodal HDPE resin has molecular weight profile that has a single peak in a GPC chromatogram; in contrast to a multimodal HDPE resin, which as a molecular weight profile that has multiple peaks or at least shoulders or tails that represent a distinct fraction having a different weight average molecular weight from the main fraction. [0041] In some embodiments, the virgin HDPE resin has a breaking stress of at least 3500 psi (24 MPa) or at least 3800 psi (26 MPa) or at least 4000 psi (27 MPa). In some embodiments, the breaking stress of the virgin HDPE resin is at most 5000 psi (35 MPa) or at most 4500 psi (31 MPa) or at most 4200 psi (29 MPa). (The conversion of units is known, 145 psi ≈ 1 MPa) [0042] In some embodiments, the virgin HDPE resin has a breaking strain of at least 5 percent or at least 7 percent or at least 9 percent. In some embodiments, the breaking strain of the virgin HDPE resin is at most 20 percent or at most 15 percent or at most 13 percent or at most 11 percent. [0043] In some embodiments, the virgin HDPE resin has a flexural modulus of at least 100 ksi (690 MPa) or at least 120 ksi (830 MPa) or at least 140 ksi (965 MPa). In some embodiments, the flexural modulus of the virgin HDPE resin is at most 200 ksi (1400 MPa) or at most 180 ksi (1250 MPa) or at most 160 ksi (1100 MPa). (1 ksi = 1000 psi.) [0044] HDPE resins can be made by known processes, such as solution, slurry and/or gas-phase polymerization of ethylene monomer and optionally comonomers in the presence of Ziegler-Natta catalysts, metallocene catalysts or other single site catalysts. In some embodiments, the catalyst is a Ziegler-Natta catalyst. HDPE Compositions [0045] The HDPE composition comprises a recycled HDPE resin and a virgin HDPE resin. The recycled HDPE resin and the virgin HDPE resin can be melt-blended together to form the HDPE composition. The recycled HDPE resin and the virgin HDPE resin are blended such that the weight percent of virgin HDPE resin (W_v), based solely on the combined weight of virgin HDPE resin and recycled HDPE resin, meets the following equations: W_v ≥ [ (0.66 dg/min - MI_r ^(-0.257)) / (MI_v ^(-0.257) - MI_r ^(-0.257))] x 100/dg/min. Wv ≤ [1-(0.2125MIr+ 0.0025MIv)] x 100/dg/min, and wherein MI_r is the melt index (I₂) of the recycled HDPE resin and MI_v is the melt index (I₂) of the virgin HDPE resin. The weight percent of recycled HDPE resin (W_r), based solely on the combined weight of virgin HDPE resin and recycled HDPE resin, is 100 - Wv. Of course, all values of Wv and Wr must be greater than 0 (> 0) and less than 100 (< 100). [0046] In some embodiments, • Wv ≥ [(0.2250MIr+ 0.0025MIv)/dg/min] x 100; or • W_v ≥ [(0.2500MI_r+ 0.0025MI_v)/dg/min] x 100. [0047] In some embodiments, • W_v ≤ [ (0.655 dg/min - MI_r ^(-0.257)) / (MI_v ^(-0.257) - MI_r ^(-0.257))] x 100/dg/min; or • Wv ≤ [ (0.65 dg/min - MIr^(-0.257)) / (MIv^(-0.257) - MIr^(-0.257))] x 100/dg/min; or • Wv ≤ [ (0.64 dg/min - MIr^(-0.257)) / (MIv^(-0.257) - MIr^(-0.257))] x 100/dg/min. [0048] In some embodiments, the HDPE composition comprises at least 12 weight percent recycled HDPE resin or at least 14 weight percent or at least 18 weight percent or at least 20 weight percent or at least 22 weight percent or at least 24 weight percent or at least 25 weight percent, based solely on the combined weight of virgin HDPE resin and recycled HDPE resin. In some embodiments, the HDPE composition comprises at most 50 weight percent recycled HDPE resin or at most 43 weight percent or at most 41 weight percent or at most 36 weight percent or at most 30 weight percent, based solely on the combined weight of virgin HDPE resin and recycled HDPE resin. For example, the HDPE composition may comprise from 15 to 30 weight percent recycled HDPE resin, based solely on the combined weight of virgin HDPE resin and recycled HDPE resin, or from 19 to 34 weight percent, or from 20 to 36 weight percent, or from 21 to 36 weight percent. [0049] In some embodiments, the HDPE composition comprises at most 88 weight percent virgin HDPE resin, based solely on the combined weight of virgin HDPE resin and recycled HDPE resin, or at most 86 weight percent or at most 82 weight percent or at most 80 weight percent or at most 78 or at most 76 weight percent or at most 75 weight percent weight percent. In some embodiments, the HDPE composition comprises at least 50 weight percent virgin HDPE resin, based solely on the combined weight of virgin HDPE resin and recycled HDPE resin, or at least 57 weight percent or at least 59 weight percent or at least 64 weight percent or at least 70 weight percent. For example, the HDPE composition may contain from 70 to 85 weight percent virgin HDPE resin, based solely on the combined weight of virgin HDPE resin and recycled HDPE resin, or from 66 to 81 weight percent, or from 64 to 79 weight percent. [0050] In some specific embodiments of the invention, the HDPE composition has values of MIr, MIv, Wr, and Wv as follows: • MIr is 0.60 dg/min to 0.70 dg/min, MIv is 2.90 dg/min to 54 dg/min, Wr is 14% to 40%, and Wv is 60% to 86%. (Alternatively, Wr is 14% to 38% and Wv is 62% to 86%.); or • MI_r is 0.65 dg/min to 0.70 dg/min, MI_v is 2.90 dg/min to 50 dg/min, W_r is 15% to 40%, and W_v is 60% to 85%. (Alternatively, W_r is 16% to 38% and W_v is 62% to 84%.); or • MI_r is 0.70 dg/min to 0.80 dg/min, MI_v is 2.5 dg/min to 45 dg/min, W_r is 16% to 42%, and W_v is 58% to 84%. (Alternatively, W_r is 16% to 39% and W_v is 61% to 84%.) All percentages are by weight, based solely on the combined weight of recycled HDPE resin and virgin HDPE resin. [0051] In other specific embodiments of the invention, the HDPE composition has values of MIr, MIv, Wr, and Wv as follows: • MIr is 0.60 dg/min to 0.70 dg/min, MIv is 37 dg/min to 53 dg/min, Wr is 24% to 40%, and Wv is 60% to 76%. (Alternatively, Wr is 24% to 38% and Wv is 62% to 76%.); or • MI_r is 0.65 dg/min to 0.70 dg/min, MI_v is 37 dg/min to 50 dg/min, W_r is 24% to 40%, and W_v is 60% to 76%. (Alternatively, Wr is 24% to 38% and Wv is 62% to 76%.); or • MI_r is 0.70 dg/min to 0.80 dg/min, MI_v is 22 dg/min to 40 dg/min, W_r is 25% to 42%, and W_v is 58% to 75%. (Alternatively, W_r is 25% to 38% and W_v is 62% to 75%.) All percentages are by weight, based solely on the combined weight of recycled HDPE resin and virgin HDPE resin. [0052] In some embodiments, the HDPE composition may contain additives. In some embodiments, additives make up no more than 5 weight percent of the HDPE composition or no more than 4 weight percent or no more than 3 weight percent or no more than 2 weight percent or no more than 1 weight percent. In some embodiments, additives make up essentially 0 weight percent of the HDPE composition. [0053] In some embodiments, the HDPE composition has a density of at least 0.950 g/cc or at least 0.952 g/cc or at least 0.954 g/cc or at least 0.955 g/cc. In some embodiments, the HDPE composition has a density of at most 0.970 g/cc or at most 0.968 g/cc or at most 0.967 g/cc or at most 0.960 g/cc. [0054] In some embodiments, the HDPE composition has a melt index (I2) of at least 2.5 dg/min or at least 3.0 dg/min or at least 5.0 dg/min or at least 7.0 dg/min. In some embodiments, the melt index (I2) of the HDPE composition is at most 15 dg/min or at most 12 dg/min or at most 10 dg/min. The melt indices achieved by the HDPE compositions indicate ease of processability in injection molding processes. [0055] In some embodiments, the HDPE composition has a melt flow ratio (I10/I2) of at least 8.0 or at least 8.2 or at least 8.5. In some embodiments, the melt flow ratio (I10/I2) of the HDPE composition is at most 12 or at most 11 or at most 10. [0056] In some embodiments, the HDPE composition has a melt flow ratio (I21/I2) of at least 20 or at least 22 or at least 24 or at least 26. In some embodiments, the melt flow ratio (I21/I2) of the HDPE composition is at most 45 or at most 40 or at most 38 or at most 36 or at most 33 or at most 30. _[0057] In some embodiments, the HDPE composition has a molecular weight distribution (M_w/M_n) of at least 4.0 or at least 4.5 or at least 4.8 or at least 5.0. In some embodiments, the molecular weight distribution (Mw/Mn) of the HDPE composition is at most 10 or at most 8 or at most 6. [0058] In some embodiments, the HDPE composition has a yield strain measured at 500 mm/min of at least 2 percent or at least 3 percent at least 4 percent or at least 5 percent or at least 6 percent or at least 7 percent. In some embodiments, the yield strain of the HDPE composition measured at 500 mm/min is at most 20 percent or at most 15 percent. In some embodiments, the HDPE composition has a yield strain measured at 50 mm/min of at least 2 percent or at least 3 percent at least 4 percent or at least 5 percent. In some embodiments, the yield strain of the HDPE composition measured at 50 mm/min is at most 20 percent or at most 15 percent. [0059] In some embodiments, the HDPE composition has a break strain measured at 500 mm/min of at least 10 percent or at least 12 percent at least 14 percent or at least 16 percent or at least 18 percent or at least 20 percent. In some embodiments, the break strain of the HDPE composition measured at 500 mm/min is at most 30 percent or at most 25 percent. In some embodiments, the HDPE composition has a break strain measured at 50 mm/min of at least 5 percent or at least 6 percent at least 7 percent or at least 8 percent or at least 9 percent or at least 10 percent. In some embodiments, the break strain of the HDPE composition measured at 500 mm/min is at most 30 percent or at most 25 percent. [0060] In some embodiments, the HDPE composition has a flexural modulus measured at 0.05 in/sec of at least 135 ksi (930 MPa) or at least 145 ksi (1000 MPa) or at least 155 ksi (1070 MPa) or at least 160 ksi (1100 MPa). In some embodiments, the flexural modulus of the HDPE composition measured at 0.05 in/sec is at most 250 ksi (1730 MPa) or at most 200 ksi (1380 MPa) or at most 180 ksi (1240 MPa). In some embodiments, the HDPE composition has a flexural modulus measured at 0.5 in/sec of at least 135 ksi (930 MPa) or at least 145 ksi (1000 MPa) or at least 155 ksi (1070 MPa) or at least 160 ksi (1100 MPa) or at least 180 ksi (1240 MPa) or at least 200 ksi (1380 MPa). In some embodiments, the flexural modulus of the HDPE composition measured at 0.5 in/sec is at most 300 ksi (2068 Mpa) or at most 250 ksi (1730 Mpa) or at most 230 ksi (1586Mpa). (1 ksi = 1000 psi) [0061] In some embodiments, the HDPE composition has a 2% secant modulus measured at 0.05 in/sec of at least 140 ksi (965 MPa) or at least 150 ksi (1030 MPa) or at least 155 ksi (1070 MPa). In some embodiments, the HDPE composition has a 2% secant modulus measured at 0.05 in/sec of at most 250 ksi (1730 MPa) or at most 200 ksi (1380 MPa). In some embodiments, the HDPE composition has a 2% secant modulus measured at 0.5 in/sec of at least 140 ksi (965 MPa) or at least 150 ksi (1030 MPa) or at least 155 ksi (1070 MPa). In some embodiments, the 2% secant modulus of the HDPE composition measured at 0.5 in/sec is at most 250 ksi (1730 MPa) or at most 200 ksi (1380 MPa). [0062] In some embodiments, the HDPE composition has a shrinkage anisotropy of at most 1.8 or 1.7 or 1.6 or 1.5 or 1.4 or 1.3 or 1.2. In some embodiments, the shrinkage anisotropy of the HDPE composition is at least 1.1 or 1.2. [0063] A process for making the HDPE composition is also disclosed. The process comprises: (a) providing a recycled HDPE resin having a density from 0.940 g/cc to 0.970 g/cc, a melt index (MI_r) from 0.50 to 1.00 dg/min, and a molecular weight distribution (M_w/M_n) from 8 to 15; (b) a virgin HDPE resin having a density from 0.940 g/cc to 0.970 g/cc, a melt index (MI_v) from 2/MI_r dg/min to 32/MI_r dg/min, and a molecular weight distribution (M_w/M_n) from 2 to 5; (c) melt blending a weight percent of the virgin HDPE resin (W_v) with a weight percent of the recycled HDPE resin (W_r), based solely on combined weight of the virgin HDPE resin and the recycled HDPE resin, wherein W_r = 100 - W_v, and W_v is calculated according to the following equations: W_v ≥ [ (0.66 dg/min - MI_r ^(-0.257)) / (MI_v ^(-0.257) - MI_r ^(-0.257))] x 100 dg/min; and W_v ≤ [1 - (0.2125MI_r+ 0.0025MI_v)] x 100 dg/min; and wherein the MI_r and MI_v are (I₂) and determined according to ASTM D1238 at 190°C, 2.16 kg. The HDPE composition can be made by melt-blending the recycled HDPE resin and the virgin HDPE resin, optionally with other additives. In summary, powders or pellets of the recycled HDPE resin and the virgin HDPE resin are subjected to heat and shear in an extruder, blender or kneader or similar equipment until they melt and become homogeneously blended together. In some embodiments, the melt temperature during blending is at least 180℃ or at least 185℃ or at least 190℃. In some embodiment, the melt temperature during blending is at most 210℃ or at most 205℃ or at most 200℃. [0064] The melt blended HDPE composition can be fabricated to make molded articles after it is blended while still molten, such as by feeding from the extruder into an injection molding, blow-molding or compression molding or other end use process. [0065] Alternatively, the melt blended HDPE composition can be made into pellets or other intermediate form for convenient storage and shipping, such as by extruding, chopping and cooling the molten HDPE composition. In this embodiment, the HDPE composition may be considered “preblended” because the HDPE composition is melt-blended before it is needed and then fixed in a convenient form for storage and shipping. Shaped Articles and Their Production [0066] The HDPE compositions of this invention can be used in conventional fabrication processes to make shaped articles, such as injection molding, compression molding, and blow molding. Each of these processes is well-known and described in many publications, and equipment to practice it is commercially available. [0067] An injection molding process comprises the steps of: (1) injecting the high density polyethylene composition according to embodiments disclosed herein into a mold; (2) cooling the high density polyethylene composition in the mold until solidified to form the molded article. [0068] In a compression molding process, a two-piece mold provides a cavity having the shape of a desired molded article. The mold is heated, and an appropriate amount of molten HDPE composition is loaded into the lower half of the mold. The two parts of the mold are brought together under pressure. The HDPE composition, softened by heat, is thereby welded into a continuous mass having the shape of the cavity. The continuous mass may be hardened via chilling under pressure in the mold, and released from the mold. [0069] Blow molding processes include extrusion blow molding, injection blow molding and injection stretch blow molding. [0070] In an extrusion blow molding process, the HDPE composition is melted and extruded as a hollow tube, called a parison. The parison is enclosed in a cooled metal mold for a shaped article such as a bottle, container, or part. Air or a neutral gas such as nitrogen is then blown into the parison, inflating it into the shape of the mold. After the HDPE composition has cooled sufficiently, the mold is opened, and the part is ejected. [0071] In an injection blow molding process, the HDPE composition is melted and injected into a metal mold for a shaped article such as a bottle, container, or part. Air or a neutral gas such as nitrogen is then blown into the mold, inflating the HDPE composition into the shape of the mold. After the HDPE composition has cooled sufficiently, the mold is opened, and the part is ejected. [0072] In an injection stretch blow molding process, a preform of the HDPE composition is made by injection molding. In some embodiments, the final neck features for the final molded item (such as threading on a bottle neck) are made on the preform. Next, the molten preform is placed in a mold. Air or a neutral gas such as nitrogen is then blown into the preform, inflating it into the shape of the mold. After the HDPE composition has cooled sufficiently, the mold is opened, and the part is ejected. The preform may be blown immediately after it is formed, or it may be cooled and then reheated and blown later. [0073] Each of these processes makes a molded or shaped article comprising the composition of the present invention. Shaped articles can come in a variety of shapes and sizes, from small articles such as pill bottles, to medium articles such as drink bottles, to large items such as outdoor furniture, trash cans and auto parts. In some embodiments, the composition of the present invention may be the only polymer in the shaped article. In some embodiments, the shaped article may contain layers or zones of different polymers to serve different purposes in the article. [0074] In some embodiments, HDPE compositions of the present invention are used in injection molding processes or injection stretch blow-molding processes, as previously described. In some embodiments, the temperature of the molten HDPE composition during injection is at least 150℃ or at least 155℃ or at least 160℃. In some embodiments, the temperature of the molten HDPE composition during injection is at most 210℃ or at most 190℃ or at most 180℃. [0075] “Flow length ratio” is important in injection molding. Flow length ratio is the length that an injected polymer must flow to completely fill the mold (the length from the injection point to the farthest part of the mold cavity) divided by the thickness of the mold cavity. Small injection molded articles (such as 26-43 mm) frequently require a flow length ratio from 40 to 80. Medium sized articles (such as 80 mm to 150 mm) commonly require a flow length ratio from 150 to 250. Large sized articles (such as 550 mm to 1150 mm) can require a flow length ratio from 200 to 300. Polymers with lower melt viscosity and higher melt index may achieve higher flow length ratio. Some HDPE compositions of the present invention may be able to achieve a flow length ratio of at least 80 or at least 100 or at least 120 or at least 150 or at least 180 or at least 200. [0076] The product of the molding process is a shaped article containing an HDPE composition of this invention. In some embodiments, the molded part has a length of no more than 60 mm and/or a length to thickness ratio of less than 100. In some embodiments, the molded part has a length of 60 mm to 200 mm and/or a length to thickness ratio of 100 to 250. In some embodiments, the molded part has a length of more than 200 mm and/or a length to thickness ratio of more than 250. Compositions of this invention may be especially useful in caps and closures for containers. Test Methods Parameters described in this application can be measured using the following measurements: Parameter Test

Molecular Weight and Molecular Weight Distribution (Conventional GPC): [0077] Conventional GPC is obtained by high temperature gel permeation chromatography (GPC) equipment (PolymerChar, Spain). The IR5 detector (“measurement channel”) is used as a concentration detector. GPCOne software (PolymerChar, Spain) is used to calculate weight-average (Mw), and number- average (Mn) molecular weight of the polymer and to determine molecular weight distribution (Mw/Mn). The method uses three four 20 micron PL gel mixed A columns (Agilent Technologies, column dimension 100 X 7.6 mm) operating at a system temperature of 150 ^oC. Samples are prepared at a 2 mg/mL concentration in 1,2,4-trichlorobenzene solvent containing 200 part per million of antioxidant butylated hydroxytoluene (BHT) for 3 hours at 160 ^oC with a gentle shaking by autosampler (PolymerChar, Spain). The flow rate is 1.0 mL/min, the injection size is 200 microliters. GPCOne software is used to calculate the plate count. The chromatographic system must have a minimum of 22,000 plates. [0078] The GPC column set is calibrated by running at least 20 narrow molecular weight distribution polystyrene standards. The calibration uses a third order fit for the system with three10 micron PL gel mixed B columns or a fifth order fit for the system with four 20 micron PL gel mixed A columns. The molecular weight (MW) of the standards range from 580 g/mol to 8,400,000 g/mol, and the standards are contained in 6 “cocktail” mixtures. Each standard mixture has approximately a decade of separation between individual molecular weights. The standard mixtures are purchased from Agilent Technologies. The polystyrene standards are prepared at “0.025 g in 50 mL of solvent” for molecular weights equal to, or greater than, 1,000,000 g/mol, and at “0.05 g in 50 mL of solvent” for molecular weights less than 1,000,000 g/mol. The polystyrene standards are dissolved at 80°C, with gentle agitation, for 30 minutes. The narrow standards mixtures are run first, and in order of decreasing highest molecular weight component, to minimize degradation. The polystyrene standard peak molecular weights are converted to polyethylene molecular weights using Equation (1) (as described in Williams and Ward, J. Polym. Sci., Polym. Letters, 6, 621 (1968)): M_{W =} B P_{E A × ( MW PS )} ^{(Eq. 1)} [0079] where MW is the molecular weight of polyethylene (PE) or polystyrene (PS) as marked, and B is equal to 1.0. It is known to those of ordinary skill in the art that A may be in a range of about 0.38 to about 0.44 such that the A value yields 52,000 MWPE for Standard Reference Materials (SRM) 1475a. Use of this polyethylene calibration method to obtain molecular weight values, such as the molecular weight distribution (MWD or Mw/Mn), and related statistics, is defined here as the modified method of Williams and Ward. The number-average molecular weight, the weight-average molecular weight, and the z-average molecular weight are calculated from the following equations: M^{n,cc =} ^^{wi /} ^ ^{Mcc , i (Eq. 2) 4)}

[0080] where M_n,cc, M_w,cc, and M_z,cc (in g/mole) are the number-, weight-, and z-average molecular weight obtained from the conventional calibration, respectively. w_i is the weight fraction of the polyethylene molecules eluted at retention volume V_i. M_cc,i is the molecular weight (in g/mole) of the polyethylene molecules eluted at retention volume V_i obtained using the conventional calibration (see Equation (1)). [0081] The chromatographic peaks should be set to include area marking a significant visible departure from baseline when the chromatogram is viewed at 20 percent peak height. The baseline should not be integrated to less than 100 polyethylene-equivalent molecular weight and care must be used to account for anti-oxidant mismatch from the prepared sample and the chromatographic mobile phase. [0082] Use of a decane flow rate marker is shown in the IR5 chromatogram. At no point should the baseline (response) Y-value difference between the start and the end of the baseline be greater than 3 percent of the integrated peak height of the chromatogram. In such a case, the chromatographic sample must be handled through proper matching of the sample and mobile phase antioxidant. [0083] Gel Content: Gel analysis is conducted using an Optical Control Systems GmbH (OCS) At- line Cast film analyzer system. Polymer pellets are fed into the extruder at elevated temperature, melt mixed and then extruded through a slit die to form a thin horizontal sheet. The sheet is drawn down onto a system of chill rolls and with the aid of an air knife, a thin film is produced. As the film is brought to a target width, it passes through an imaging system that consists of a CCD digital camera, a light source and a computer running image analysis software. The imaging system is configured in transmission mode, with the film passing between the light source and the camera. As the film is illuminated, the camera measures the intensity of the transmitted light. Gels refract the light, thus reducing the amount of light signal reaching the camera. This reduction triggers a “detection”, and a digitized image of the gel is created. Pixels representing the gel appear darker than the film background; the computer analyzes these dark pixels, determining the gel’s area. The diameter of the gel is then assigned by calculating the diameter of a circle with an area equivalent to the measured gel area. Based on this derived diameter, gels are grouped into size classes – 100 μm, 200 μm, 400 μm, 800 μm, 1600 μm, and >1600 μm. EXAMPLES [0084] Six virgin HDPE Resin (named VR1-VR6) are made by gas-phase fluid-bed polymerization in the following process: UCAT™ J catalyst is partially activated by contact at room temperature with a 50 percent mineral oil solution of tri-n-hexyl aluminum (TNHA) and stirred for at least 1 hour prior to use. The following ingredients are continuously fed into a fluidized bed of polyethylene granules in a fluidized bed reactor: ethylene, 1-hexene (except VR1), hydrogen, the partially activated UCAT™ J catalyst, tetraethyl aluminum co-catalyst (2.5 wt% solution), isopentane and nitrogen. The reaction temperature is 95℃, and the reaction pressure is 348 psig (2.40 MPa). Other reaction conditions are listed in Table 1A. The resulting polymer, mixed with active catalyst, is continuously withdrawn from the reactor. Table 1A VR1 VR2 VR3 VR4 VR5 VR6 Ethylene Partial Pressure (psi) 147 148 150 150 150 150

[0085] The virgin HDPE resins made above (VR1-VR6) have the properties shown in Table 1B. The recycled HDPE resin, Ecoprime (Devolatized Natural Homopolymer High Density Polyethylene Post Consumer Resin) is commercially available and obtained from Envision Plastics (Reidsville, NC). It has the properties shown in Table 1B. DOW™ DMDA-8965 NT7 HDPE resin and DOW™ DMDA-8940 NT7 HDPE resin are obtained from The Dow Chemical Company and have properties shown in Table 1B. Table 1B R_esin ^Density I₂ (MI_v) / _{d / i} ^Mw/Mn

[0086] Note that MIr is 0.68 g/ 10 min. The target MIv for the virgin HDPE resin is: • at least 2/MIr = 2.94 g/ 10 min. and • at most 32/MIr = 47.1. VR1, VR2, VR3, VR5 and VR8 meet the target MIv for the virgin HDPE resin. VR4, VR6 and VR7 do not meet the target MIv for the virgin HDPE resin. [0087] When measured according to the Test Methods, PCR1 (Ecoprime PCR HDPE) has an ash content of 0.145 weight percent, the gel content shown in Table 2 and the visual characteristics in Table 3. Table 2 Results Gel Count > 1600 um 0

Table 3 L* 75.21 * 196

[0088] The resins are melt-blended in the proportions set out in Table 4, using a Coperion ZSK 18 MEGAlab twin screw extruder (TSE) in which L/D = 40 and D_o/D_i = 1.55. Melt-blending conditions are in Table 4: Table 4 Zone 1 temperature (°C) 175

[0089] The blends are injection molded to make test plaques using a Sodick GL 100 injection molding machine and the conditions in Table 5: Table 5 Feed Rate (lbs./hr) 10 Zone Z0 temperature (°C) 225

lts are shown in Table 6.

. 9 E _C ⁰ ₂ ⁸ _{6 8} ⁸ ₄ ^{4 .} ₀ R⁰ V ₄ ⁰ ₈ ² ₆ ⁶ ₇ ⁵ _{9 7}. ⁰ ₁ ± . ⁶ ₉ .₀ ⁷ ₁ ⁵ ₃ ^. ₄ ⁶ ₅ ² ± 9 ^{8 2} ₂ ⁸ ₁ ⁸ ₆ ± 1 ^{6 9} ₃ ^± ₆₃ ³ ₅ ¹ _{5 3} . ^. ₂ 0 ₁ 3 ₂ ⁵ _{1 6} ^. _{8 0 8} ⁸ ₈ ³ ₃ ⁵ ₉ ⁷ ₀ ⁴ ±₂ ± ₀ ^. ₅ ±² _{8 9}

V ^. _{0 1} ² ₄ ¹ ₃ ⁹ ₃ ⁴ ₂ ^. ₇ ^. ₃ ^. ₄ ^. _{1 6} ^. ₀ ⁽ _{[ 3} E _{I 2} ⁸ ₃ ⁵ ₄ ^{3 .} ₃ ³ ±₆ ± ₀ ^. ₃ = ± _{2 7 8 7} v 5 _{6 0} R^{0 5 5 8} V _{3 7 6 7} ⁵ ₉. ₇ ⁸ ₂ ^{0 .} _{2 0} ¹ ₁ ^. ₈ ^. ₅ ^{1 7 2} ₂ ^{3 ± 1} ₄ ⁹ ₂ ^{6 0 5 5} ₂ ^. W 3 ₇ ³ _{4 6 4} . 4₁ ^. ₇ ^. _{0 1 2 1 1 1} ⁿ _i M 6 ^. _{0 2 2} ¹ ₆ ± E ₅ ± ± ± ^. ₃ ± ± ± ⁰ _{1 I} ⁵ ₂ ⁸ ₆ ^. ₀ R⁰ V ₂ ⁵ ₇ ⁹ ₆ ¹ ₈ ⁵ ₉ ⁴ ₆ ⁷ ₆ ³ ₂ ^{2 .} _{7 0} ^. ₈ ^. ₈ ^. ₅ ^{1 7 6} ₈ ⁰ ₆ ⁸ ₇ ⁰ ₃ ⁶ _{1 3} 1 ^± _{9 6}. ₄ ^{. 1} ₉ ⁸ ₁ ⁰ ₆ ⁷ _{9 0} 7 ₉ 5 ₃ ^{. x} _{] 21} ² ₃ ³ ₄ ¹ _{3 2 .} 1₂ ² _{1 2} ^. ₇ ^. ₀ ^. ₆ ^. _{2 1 1 1} ⁿ _i m^/ _{g 1} ⁷ ± ³ _{4 6} ^{4 d/ 0} ₁ ^. ₎ v_I E _I ⁰ ₃ ⁸ _{6 8} .₀ R^{0 0 2 6} ₅ V _{4 7 6 7} ^{5 3} 9 ₃. ₆. ³ ₅ ^{8 .} ₀ ¹ ₁ ⁶ ₂ ^. _{5 3} ⁸ ₉ ± _{1 0 4 6} 8₁ ⁵ ₁ ⁴ ₀ ^± ₁ ± ¹ ₂ ⁵ ₁ M 9 ⁵ 3 ³ ₁ ⁵ ₀ ^. _{2 9} ⁰ ₀ ^. _{0 ) ) )} n _{) ) ) ) )} ⁾ _c +^r _I %_t ^% _{t i} w ^m _/ ⁿ _i ⁿ _i ⁿ _i ⁿ _i ^{e m n} _i ^m _/ ^m _s/ ⁾ _c es M w ^{( (} ₎ m ^m _{/ / /} m ^m _/ m m ⁿ _{i /} n_i ⁵ ₀ ^. ₅ ⁵ 0 ^{. y} _{p 2 )r} ⁿ _i v m m m m m m ₎ m ₎ ⁵ ₀ ^. ₅ ^. _{( 0 s ( s} o ^{1 r} _{t 2}. W ^{s (} _e W t R₎ ^{( v} _{t ) ) s 0} %_t ^e _{i )} ⁰ ₅₍ ⁰ ₀ m _{0 5(} ⁰ ₅ ⁰ ₅ ⁰ _{0 0 5 ( 0( (} % ^{( 0} ₅ % ⁽ _{s s} ^u _l ^u _l ^o _si ⁰(_[ n^e _t ⁾ _I ^{r E} _P I n^e _t ^% _t ^{t w} _{r (} ^{e c} _{c )}. ^s _{( ( s} ^s _s ^{s s n} _i ⁿ _{i )} n _{( ) i} ^{n u} _l ^u _l ^u _do_)i ^u _do_)i n = Av n o ^M ₍ D^M ₍ n ^w _{( C} ² H_I 2 ^o _{C1 1 p} v v o ^{/ r} _{g P (} ⁿ _i m_/ ^e _r ^e _{r s} n ^t _S ^t _S ^e _{s r} ^{t e} _r ^{a t} _r ^{t a} _r ^{n t m} _i ⁿ _{i i /} ^a _r ^{t a} _r ^{t m} _/ ^u _d ^u o _do M^{s .} _k( M^{s .} _k( ^e _g W 1 I 1 W g _{d y} ^ti ^g _{S S S S}m_{S S}mM M _c e ⁾ _{c c} e ^{) a} _k ^x _a RRⁿ _i ⁿ _i ⁿ _i W n _{s d} ⁽ _{2 2} ^M _/ ^k _a ^{) C} r _i ^k _a ⁾ _i ^d _l ⁾ _i ^d _l ⁾ _i ^k _{a )} ^k _a m^d _{l )} ^d _l m. ⁾ _i . ⁾ _{i S} ^e _{S c} e ⁿⁱ M P ^C _{P i} ^gr_i ^gr_i ⁿ _i ^x _a ^e V V V M M _l ⁿ _{e I} ^I _/ B D M I₀ ^{I 1} _/ I₁ ² w^e M_r B^s _{p (} ^e _r B^s _{p (} ^e _i Y^s _{p (} ^e _i Y^s _{p (} ^e _r ^e B^% _{( r} B⁰ _{5 (} ^e _i ^e _i Y^% ₍ Y⁰ ₅ ^x _{e (} ^l _F ^s _k ^x _{e (} ^l _F ^s _k s_/ s_{/ r (} ^% ₂ ⁿ _i ^% ₂ ⁿ _i ^h _S – 1 Table 6 continued

Claims

CLAIMS We claim: 1. A high density polyethylene composition comprising: a) a recycled HDPE resin having a density from 0.940 g/cc to 0.970 g/cc, a melt index (MI_r) from 0.50 to 1.00 dg/min, and a molecular weight distribution (Mw/Mn) from 8 to 15; and b) a virgin HDPE resin having a density from 0.940 g/cc to 0.970 g/cc, a melt index (MI_v) from 2/MI_r dg/min to 32/MI_r dg/min, and a molecular weight distribution (M_w/M_n) from 2 to 5, wherein the weight percent of the virgin HDPE resin (Wv), based solely on combined weight of the virgin HDPE resin and the recycled HDPE resin, meets the following equations: Wv ≥ [ (0.66 dg/min - MIr^(-0.257)) / (MIv^(-0.257) - MIr^(-0.257))] x 100/dg/min; and Wv ≤ [1 - (0.2125MIr+ 0.0025MIv)] x 100/dg/min; and wherein the MIr and MIv are (I2) and determined according to ASTM D1238 at 190°C, 2.16 kg. 2. The high density polyethylene composition of claim 1, wherein the recycled HDPE resin has a density from 0.958 to 0.965 g/cc, a MIr from 0.50 dg/min to 0.85 dg/min, and an ash content of at least 0.08 weight percent. 3. The high density polyethylene composition of any preceding claim, wherein the MIr is from 0.60 dg/min to 0.70 dg/min, and the MIv is from 2.90 dg/min to 54 dg/min, and wherein a weight percent of the recycled HDPE resin (Wr), based solely on combined weight of the virgin HDPE resin and the recycled HDPE resin, is from 14 weight percent to 40 weight percent. 4. The high density polyethylene composition of any preceding claim, wherein the MIr is from 0.60 dg/min to 0.70 dg/min, the MIv is from 37 dg/min to 53 dg/min, and a weight percent of the recycled HDPE resin (Wr), based solely on combined weight of the virgin HDPE resin and the recycled HDPE resin, is from 24 weight percent to 40 weight percent. 5. The high density polyethylene composition of any preceding claim, wherein the MIr is from 0.65 dg/min to 0.70 dg/min, the MIv is from 2.9 dg/min to 50 dg/min, and a weight percent of the recycled HDPE resin (Wr), based solely on combined weight of the virgin HDPE resin and the recycled HDPE resin, is from 15 weight percent to 40 weight percent. 6. The high density polyethylene composition of any preceding claim, wherein the MI_r is from 0.65 dg/min to 0.70 dg/min, the MI_v is from 37 dg/min to 50 dg/min; and a weight percent of the recycled HDPE resin (W_r), based solely on combined weight of the virgin HDPE resin and the recycled HDPE resin, is from 24 weight percent to 40 weight percent. 7. The high density polyethylene composition of claims 1-2, wherein the MI_r is from 0.70 dg/min to 0.80 dg/min, the MI_v is from 2.5 dg/min to 45 dg/min, and a weight percent of the recycled HDPE resin (Wr), based solely on combined weight of the virgin HDPE resin and the recycled HDPE resin, is from 16 weight percent to 42 weight percent. 8. The high density polyethylene composition of claims 1-2, wherein MI_r is from 0.70 dg/min to 0.80 dg/min, the MIv is from 22 dg/min to 40 dg/min, and a weight percent of the recycled HDPE resin (Wr), based solely on combined weight of the virgin HDPE resin and the recycled HDPE resin, is from 25 weight percent to 42 weight percent. 9. The high density polyethylene composition of any preceding claim, wherein the high density polyethylene composition has a melt index (I2) from 5 dg/min to 15 dg/min. 10. The high density polyethylene composition of any preceding claim, wherein the high density polyethylene composition has a density from 0.950 g/cc to 0.965 g/cc. 11. The high density polyethylene composition of any preceding claim, wherein the high density polyethylene composition has a breaking stress of at least 1700 psi. 12. The high density polyethylene composition of any preceding claim, wherein the high density polyethylene composition has a breaking strain of at least 9 percent. 13. The high density polyethylene composition of any preceding clam, wherein the high density polyethylene composition has a shrinkage anisotropy from 1.1 to 1.5. 14. A process to make a molded article comprising the steps of (1) injecting the high density polyethylene composition of any of claims 1-13 into a mold; (2) cooling the high density polyethylene composition in the mold until solidified to form the molded article. 15. A process of claim 14, wherein the mold has a flow length ratio of at least 100. 16. A process comprising: (a) providing a recycled HDPE resin having a density from 0.940 g/cc to 0.970 g/cc, a melt index (MIr) from 0.50 to 1.00 dg/min, and a molecular weight distribution (Mw/Mn) from 8 to 15; (b) a virgin HDPE resin having a density from 0.940 g/cc to 0.970 g/cc, a melt index (MI_v) from 2/MI_r dg/min to 32/MI_r dg/min, and a molecular weight distribution (M_w/M_n) from 2 to 5; (c) melt blending a weight percent of the virgin HDPE resin (W_v) with a weight percent of the recycled HDPE resin (W_r), based solely on combined weight of the virgin HDPE resin and the recycled HDPE resin, wherein W_r = 100 - W_v, and W_v is calculated according to the following equations: W_v ≥ [ (0.66 dg/min - MI_r ^(-0.257)) / (MI_v ^(-0.257) - MI_r ^(-0.257))] x 100 dg/min; and W_v ≤ [1 - (0.2125MI_r+ 0.0025MI_v)] x 100 dg/min; and wherein the MI_r and MI_v are (I₂) and determined according to ASTM D1238 at 190°C, 2.16 kg.