WO2021053411A1

WO2021053411A1 - High-density polyethylene with increased transparency

Info

Publication number: WO2021053411A1
Application number: PCT/IB2020/057290
Authority: WO
Inventors: Anantharaman Dhanabalan; Anshita SUDARSHAN; Radha Kamalakaran; Sadasivam GOPALAKRISHANAN; Maria Soliman; Mohamed Ashraf Moideen; Prem PATHAK; Abderrahman MEDDAD
Original assignee: Sabic Global Technologies B.V.
Priority date: 2019-09-20
Filing date: 2020-07-31
Publication date: 2021-03-25

Abstract

A high-density polyethylene (HDPE) composition has increased transparency and/or reduced haze. The composition is a mixture of a HDPE, a polymeric additive that is insoluble or immiscible with the HDPE, and a clarifying and/or nucleating agent in an amount of 50 ppm to 500 ppm by total weight of the HDPE composition. The HDPE composition has at least one of a transparency of from 80% or more and a haze of from 60% or less as determined by ASTM D1003 at a thickness of from 1 mm or more.

Description

HIGH-DENSITY POLYETHYLENE WITH INCREASED TRANSPARENCY

TECHNICAL FIELD

[0001] The invention relates to high-density polyethylene compositions that have improved transparency and/or reduced haze.

BACKGROUND

[0002] Though high-density polyethylene (HDPE) has been widely used to fabricate rigid parts and objects, including small and large containers and caps and closures owing its excellent mechanical and environmental stress cracking resistance (ESCR) performances, its use in transparent applications is limited. This is due to its inherently opaque or translucent appearance. Though one can potentially improve the transparency (or reduce the total haze) via several post-processing steps, such as stretching or drawing to a different extent, both with and without additives, such methods are not commercially or economically viable. As a result, there is a need to improve the transparency of HDPE compositions towards expanding their applications into transparent segments.

SUMMARY

[0003] A high-density polyethylene (HDPE) composition having increased transparency and/or reduced haze comprises a mixture of a HDPE, a polymeric additive that is insoluble or immiscible with the HDPE, and a clarifying and/or nucleating agent in an amount of 50 ppm to 500 ppm by total weight of the HDPE composition. The HDPE composition has at least one of a transparency of from 80% or more and a haze of from 60% or less as determined by ASTM D1003 at a thickness of from 1 mm or more.

[0004] The HDPE composition may have at least one of a transparency of from 90% or more and a haze of from 50% or less as determined by ASTM D1003 at a thickness of from 1 mm or more, without drawing, stretching or orienting the HDPE composition.

[0005] The HDPE may be at least one of a unimodal, bimodal, and multimodal HDPE. In particular embodiments the HDPE may have an average molecular weight (Mw) of from 130,000 to 300,000 as determined by high temperature gel permeation chromatography; a poly dispersity index (PDI = Mw/Mn) of from 2 to 25 as determined by high temperature gel permeation chromatography; a melt flow rate (MFR) at 190 °C and 5 kg of from 0.1 g/10 min to 20 g/10 min as per ISO 1133; and/or a density of from 940 kg/m3 to 965 kg/m3 as per ASTM D1505.

[0006] In particular applications, the polymeric additive may be present in the HDPE composition in an amount of from 0.1 wt.% to 5 wt.% by total weight of the HDPE composition. The polymeric additive may be a polymer containing functional groups of at least one of an OH group, an ionic group, a norbornyl group, an ether (ROR') group, a cyclic olefin group, and a cyclic amide group. The polymeric additive may be a low molecular weight polyethylene glycol (PEG), a high molecular weight polyethylene glycol (PEG), a silyated PEG, an ethylene vinyl alcohol (EVOH) having an ethylene content of from 25 mol% to 50 mol%, an ethylene vinyl acetate (EVA), a polyvinylpyrrolidone (PVP), an ionomeric polyethylene, a cyclic olefin copolymer, and/or a sytrenic copolymer, and combinations thereof.

[0007] The clarifying and/or nucleating agent may be present in the HDPE composition in an amount of 100 ppm to 200 ppm by total weight of the HDPE composition. The clarifying and/or nucleating agent may be a sorbitol derivative, 1,2,3,4-bis-dibenzylidene sorbitol (DBS), l,2,3,4-bis-(p-methoxybenzylidene sorbitol) (DOS), l,2,3,4-bis-(3,4-dimethylbenzylidene sorbitol) (MBDS), and l,3:2,4-di(3,4-dimethylbenzylidene) sorbitol (DMDBS), a calcium salt of dicarboxylic acid, a metal salt of cyclohexane dicarboxylic acid, a bisamide, a lithium carbonate, a benzoic acid, an inorganic oxide, nano-zinc oxide, talc, clay, a powdered polymeric agent, polyphenylene oxide, polyvinylenedifluoride, polycarbonate, polycarbonate- siloxane copolymer, cross-linked polycarbonate, polyetherimide, polyamide, ethylene propylene diene monomer, and/or polyoxymethylene.

[0008] The HDPE may be a copolymer with comonomers selected from C3 to C10 olefin monomers, the comonomers being present in the HDPE copolymer in an amount of from 2 wt.% or less.

[0009] In certain embodiments, the HDPE composition may further contain one or more of a heat conductive agent, a tie agent, an antiblocking agent, an antistatic agent, an antioxidant, a neutralizing agent, an acid scavenger, a blowing agent, a crystallization aid, a dye, a flame retardant agent, a filler, a hard filler, a soft filler, an impact modifier, a mold release agent, an oil, another polymer, a pigment, a processing agent, a reinforcing agent, a stabilizer, a light stabilizer, an UV resistance agent, a slip agent, a flow modifying agent, and combinations thereof. [0010] The HDPE composition may be formed into an article of manufacture. The article may be at least one of a film, a molded part, a container, a beverage container cap, a lid, a sheet, a pipe, a pipe coupling, a bottle, a cup, a bay, a pallet, and a toy.

[0011] In a particular application, a high-density polyethylene (HDPE) composition has increased transparency and/or reduced haze comprises a mixture of a HDPE, a polymeric additive that is insoluble or immiscible with the HDPE in an amount of from of from 0.1 wt.% to 2 wt.% by total weight of the HDPE composition, and a clarifying and/or nucleating agent in an amount of 100 ppm to 500 ppm by total weight of the HDPE composition. The HDPE composition has at least one of a transparency of from 80% or more and a haze of from 40% or less as determined by ASTM D1003 at a thickness of from 1 mm or more, without drawing, stretching or orienting the HDPE composition. The polymeric additive is selected from at least one of, a low molecular weight polyethylene glycol (PEG), a high molecular weight polyethylene glycol (PEG), a silyated PEG, an ethylene vinyl alcohol (EVOH) having an ethylene content of from 25 mol% to 50 mol%, an ethylene vinyl acetate (EVA), a polyvinylpyrrolidone (PVP), an ionomeric polyethylene, a cyclic olefin copolymer, a styrenic copolymer, and combinations thereof. The clarifying and/or nucleating agent is selected from at least one of a sorbitol derivative, 1,2,3,4-bis-dibenzylidene sorbitol (DBS), l,2,3,4-bis-(p- methoxybenzylidene sorbitol) (DOS), l,2,3,4-bis-(3,4-dimethylbenzylidene sorbitol) (MBDS), and l,3:2,4-di(3,4-dimethylbenzylidene) sorbitol (DMDBS), a calcium salt of dicarboxylic acid, a metal salt of cyclohexane dicarboxylic acid, a bisamide, a lithium carbonate, a benzoic acid, an inorganic oxide, nano-zinc oxide, talc, clay, a powdered polymeric agent, polyphenylene oxide, polyvinylenedifluoride, polycarbonate, polycarbonate-siloxane copolymer, cross-linked polycarbonate, polyetherimide, polyamide, ethylene propylene diene monomer, and polyoxymethylene.

[0012] In some instances, the clarifying and/or nucleating agent is present in an amount of 100 ppm to 200 ppm by total weight of the HDPE composition.

[0013] The HDPE may be at least one of a unimodal, bimodal, and multimodal HDPE. In certain embodiments, the HDPE may have an average molecular weight (Mw) of from 130,000 to 300,000 as determined by high temperature gel permeation chromatography; a poly dispersity index (PDI = Mw/Mn) of from 13 to 25 as determined by high temperature gel permeation chromatography; a melt flow rate (MFR) at 190 °C and 5 kg of from 0.1 g/10 min to 20 g/10 min as per ISO 1133; and/or a density of from 940 kg/m3 to 965 kg/m3 as per ASTM D1505. [0014] The HDPE composition may be formed into an article of manufacture. The article may be a film, a molded part, a container, a bottle, a beverage container cap, a lid, a sheet, a pipe, a pipe coupling, a bottle, a cup, a tray, a pallet, or a toy.

[0015] In a method of forming a high-density polyethylene (HDPE) composition having increased transparency and/or reduced haze, an HDPE is modified by combining the HDPE with a polymeric additive that is insoluble or immiscible with the HDPE, and a clarifying and/or nucleating agent in an amount of 100 ppm to 500 ppm by total weight of the HDPE composition so that the HDPE composition has at least one of a transparency of from 80% or more and a haze of from 60% or less as determined by ASTM D1003 at a thickness of from 1 mm or more.

DETAILED DESCRIPTION

[0016] The present invention is related to the development of high-density polyethylene (HDPE) compositions, which may be used in various applications, such as blow/injection/compression moldable applications, with improved transparency. This includes several packaging applications, including caps and closures, trays, pipes, toys, chemical containers, shampoo bottles, milk jugs, recycling bins, and industrial bulk containers. Given the growing demand for aesthetics and see-through features of plastic parts (for example, caps and closure, bottles and containers), an enhanced optically transparent plastic becomes more vital. Bottles that are less opaque than those traditionally used have been placed on the market recently. The use of bottles having greater clarity can be aesthetically appealing to consumers. Such greater clarity allows the consumer to see the consistency of the product, any suspended particles if they are present, separation of phases if a dual phase composition is present, and other aspects or properties of materials contained in such bottles, such as laundry liquid products. Transparent bottles may also be appealing to consumers during use as it enables the consumer to ascertain easily how much product remains. The reduction of total haze of molded parts, as demanded by the consumers, while maintaining the inherent mechanical strength and processability of the HDPE is an emerging challenge. In comparison to transparent glass, the transparent HDPE composition is envisaged to have light weight and higher impact resistance. Moreover, the transparent HDPE composition is envisaged to have better hydrolytic stability and moisture barrier resistance, as compared to transparent polymers such as polycarbonate and polymethylmethacrylate.

[0017] It has been discovered that the transparency of HDPE can be increased by incorporating various optics-enhancing additives. Additionally, the total haze of the HDPE can be reduced by the use of such optics-enhancing additives. These optics-enhancing additives are incorporated into a unimodal, bimodal or multimodal HDPE, or a blend of these, by melt blending the optics-enhancing additives with the HDPE. The amount and the type of the optics enhancing additives incorporated into the HDPE is selected so that the processability of the HDPE remains relatively unaffected while its transparency and/or reduction in haze is enhanced.

[0018] The HDPE polymers used in the polymer blend can include those prepared by any of the polymerization processes, which are in commercial use (e.g., a “high pressure” process, a slurry process, a solution process and/or a gas phase process) and with the use of any of the known catalysts (e.g., multisite catalysts such as Ziegler Natta catalysts, and/or single site catalysts such as chromium or Phillips catalysts, metallocene catalysts, and the like). As used herein, where the phrase or term “high-density polyethylene” or “HDPE” is used, it should be construed without characterization as unimodal, bimodal or multimodal HDPE unless otherwise specified.

[0019] All or a major portion of the HDPE component may be unimodal or bimodal HDPE, either alone or as a blend. The unimodal and/or hi modal HDPE or combination of such HDPE materials may make up from 50 wt.% or greater of the HDPE component or from 50 wt.% to 100 wt.% of the HDPE component. In particular embodiments, the HDPE component may comprise unimodal and/or hi modal HDPE in an amount of from at least, equal to, and/or between any two of 50 wt.%, 51 wt.%, 52 wt.%, 53 wt.%, 54 wt.%, 55 wt.%, 56 wt.%, 57 wt.%, 58 wt.%, 59 wt.%, 60 wt.%, 61 wt.%, 62 wt.%, 63 wt.%, 64 wt.%, 65 wt.%, 66 wt.%, 67 wt.%, 68 wt.%, 69 wt.%, 70 wt.%, 71 wt.%, 72 wt.%, 73 wt.%, 74 wt.%, 75 wt.%, 76 wt.%,

77 wt.%, 78 wt.%, 79 wt.%, 80 wt.%, 81 wt.%, 82 wt.%, 83 wt.%, 84 wt.%, 85 wt.%, 86 wt.%,

87 wt.%, 88 wt.%, 89 wt.%, 90 wt.%, 91 wt.%, 92 wt.%, 93 wt.%, 94 wt.%, 95 wt.%, 96 wt.%,

97 wt.%, 98 wt.%, 99 wt.%, and 100 wt.%. In particular embodiments, the HDPE component may comprise unimodal and/or hi modal HDPE in an amount of from 80 wt.% to 100 wt.%. If less than 100 wt.% of unimodal and/or hi modal HDPE is used for the HDPE component, the remainder may be made up of multimodal HDPE. In certain aspects, the polymer blends of the present invention do not include polypropylene.

[0020] In other embodiments, all or a major portion of the HDPE component may be multimodal HDPE. The multimodal HDPE may make up from 50 wt.% or greater of the HDPE component or from 50 wt.% to 100 wt.% of the HDPE component. In particular embodiments, the HDPE component may comprise multimodal HDPE in an amount of from at least, equal to, and/or between any two of 50 wt.%, 51 wt.%, 52 wt.%, 53 wt.%, 54 wt.%, 55 wt.%, 56 wt.%, 57 wt.%, 58 wt.%, 59 wt.%, 60 wt.%, 61 wt.%, 62 wt.%, 63 wt.%, 64 wt.%, 65 wt.%, 66 wt.%, 67 wt.%, 68 wt.%, 69 wt.%, 70 wt.%, 71 wt.%, 72 wt.%, 73 wt.%, 74 wt.%, 75 wt.%,

76 wt.%, 77 wt.%, 78 wt.%, 79 wt.%, 80 wt.%, 81 wt.%, 82 wt.%, 83 wt.%, 84 wt.%, 85 wt.%,

86 wt.%, 87 wt.%, 88 wt.%, 89 wt.%, 90 wt.%, 91 wt.%, 92 wt.%, 93 wt.%, 94 wt.%, 95 wt.%,

96 wt.%, 97 wt.%, 98 wt.%, 99 wt.%, and 100 wt.%. In particular embodiments, the HDPE component may comprise multimodal HDPE in an amount of from 80 wt.% to 100 wt.%. If less than 100 wt.% of multimodal HDPE is used for the HDPE component, the remainder may be made up of unimodal and/or bimodal HDPE. If less than 100 wt.% of unimodal and/or hi modal HDPE is used for the HDPE component, the remainder may be made up of multimodal HDPE. In certain aspects, the polymer blends of the present invention do not include polypropylene.

[0021] It should be noted in the description, if a numerical value, concentration or range is presented, each numerical value should be read once as modified by the term "about" (unless already expressly so modified), and then read again as not so modified unless otherwise indicated in context. Also, in the description, it should be understood that an amount range listed or described as being useful, suitable, or the like, is intended that any and every value within the range, including the end points, is to be considered as having been stated. For example, “a range of from 1 to 10” is to be read as indicating each and every possible number along the continuum between about 1 and about 10. Thus, even if specific points within the range, or even no point within the range, are explicitly identified or referred to, it is to be understood that the inventor appreciates and understands that any and all points within the range are to be considered to have been specified, and that inventor possesses the entire range and all points within the range, including smaller ranges within the larger ranges.

[0022] In certain applications, the HDPE component of the polymer blend will constitute homopolymers of ethylene. These may include homopolymers solely of neat HDPE. In other embodiments, the HDPE component can include copolymers of ethylene with at least one C3 to C10 alpha olefin. Typically, this will be at least one of the alpha olefins of butene, hexene, and/or octene. In some embodiments the HDPE is a copolymer with 1 -butene (polyethylene- 1 -butene) or 1 -hexene (polyethylene- 1 -hexene). When such copolymers are used, the non ethylene comonomer may be present in the HDPE copolymer in an amount of from 2 wt.%, 1.5 wt.%, 1 wt.%, 0.5 wt.%, 0.1 wt.% or less. In particular embodiments, there is no butene or no C3 to C10 alpha olefin comonomer. Those amount percentages of multimodal HDPE, hi modal HDPE, and/or unimodal HDPE presented previously for the HDPE component may include such HDPE incorporating such copolymers.

[0023] In certain embodiments, the main HDPE component may be an un-functionalized neat HDPE with no functional groups along the polymer chain. In particular embodiments, the HDPE contains anhydride modified HDPE as an additive which is present in an amount of from 2 wt.%, 1.5 wt.%, 1 wt.%, 0.5 wt.%, 0.1 wt.% or less.

[0024] The HDPE can be characterized by various properties such as average molecular weight, poly dispersity index, density, the melt flow rates (MFR), ESCR, tensile strength at yield, tensile modulus, tensile elongation at yield, Izod notched impact strength, hardness or combinations thereof. [0025] The average molecular weight (Mw) of the HD PE may range from 130,000 to 300,000 as determined by high temperature gel permeation chromatography. In particular, the average molecular weight (Mw) of the HDPE may be from at least, equal to, and/or between any two of 130,000, 140,000, 150,000, 160,000, 170,000, 180,000, 190,000, 200,000, 210,000, 220,000, 230,000, 240,000, 250,000, 260,000, 270,000, 280,000, 290,000, and 300,000 as determined by high temperature gel permeation chromatography. Unless otherwise specified, all average molecular weights (Mw) for those polymers described herein are those determined by high temperature gel permeation chromatography.

[0026] The density of the HDPE can be from 940 kg/m³ or 945 kg/m³ to 965 kg/m³. In particular, the density of the HDPE may be from at least, equal to, and/or between any two of

940 kg/m³, 941 kg/m³, 942 kg/m³, 943 kg/m³, 944 kg/m³, 945 kg/m³, 946 kg/m³, 947 kg/m³,

948 kg/m³, 949 kg/m³, 950 kg/m³, 951 kg/m³, 952 kg/m³, 953 kg/m³, 954 kg/m³, 955 kg/m³,

956 kg/m³, 957 kg/m³, 958 kg/m³, 959 kg/m³, 960 kg/m³, 961 kg/m³, 962 kg/m³, 963 kg/m³,

964 kg/m³, and 965 kg/m³. In some applications, the density of the HDPE may range from 955 kg/m³ to 965 kg/m³.

[0027] The HDPE can have a MFR at 190 °C and 5 kg of from 0.1 g/10 min to 20 g/10 min as per ISO 1133, or at least, equal to, and/or between any two of 0.1 g/10 min, 0.2 g/10 min, 0.3 g/10 min, 0.4 g/10 min, 0.5 g/10 min, 0.6 g/10 min, 0.7 g/10 min, 0.8 g/10 min, 0.9 g/10 min, 1.0 g/10 min, 1.1 g/10 min, 1.2 g/10 min, 1.3 g/10 min, 1.4 g/10 min, 1.5 g/10 min, 1.6 g/10 min, 1.7 g/10 min, 1.8 g/10 min, 1.9 g/10 min, 2.0 g/10 min, 2.1 g/10 min, 2.2 g/10 min, 2.3 g/10 min, 2.4 g/10 min, 2.5 g/10 min, 2.6 g/10 min, 2.7 g/10 min, 2.8 g/10 min, 2.9 g/10 min, 3.0 g/10 min, 3.1 g/10 min, 3.2 g/10 min, 3.3 g/10 min, 3.4 g/10 min, 3.5 g/10 min, 3.6 g/10 min, 3.7 g/10 min, 3.8 g/10 min, 3.9 g/10 min, 4.0 g/10 min, 4.1 g/10 min, 4.2 g/10 min, 4.3 g/10 min, 4.4 g/10 min, 4.5 g/10 min, 4.6 g/10 min, 4.7 g/10 min, 4.8 g/10 min, 4.9 g/10 min, 5.0 g/10 min, 5.1 g/10 min, 5.2 g/10 min, 5.3 g/10 min, 5.4 g/10 min, 5.5 g/10 min, 5.6 g/10 min, 5.7 g/10 min, 5.8 g/10 min, 5.9 g/10 min, 6.0 g/10 min, 6.1 g/10 min, 6.2 g/10 min, 6.3 g/10 min, 6.4 g/10 min, 6.5 g/10 min, 6.6 g/10 min, 6.7 g/10 min, 6.8 g/10 min, 6.9 g/10 min, 7.0 g/10 min, 7.1 g/10 min, 7.2 g/10 min, 7.3 g/10 min, 7.4 g/10 min, 7.5 g/10 min, 7.6 g/10 min, 7.7 g/10 min, 7.8 g/10 min, 7.9 g/10 min, 8.0 g/10 min, 8.1 g/10 min, 8.2 g/10 min, 8.3 g/10 min, 8.4 g/10 min, 8.5 g/10 min, 8.6 g/10 min, 8.7 g/10 min, 8.8 g/10 min, 8.9 g/10 min, 9.0 g/10 min, 9.1 g/10 min, 9.2 g/10 min, 9.3 g/10 min, 9.4 g/10 min, 9.5 g/10 min, 9.6 g/10 min, 9.7 g/10 min, 9.8 g/10 min, 9.9 g/10 min, 10.0 g/10 min, 10.1 g/10 min, 10.2 g/10 min, 10.3 g/10 min, 10.4 g/10 min, 10.5 g/10 min, 10.6 g/10 min, 10.7 g/10 min, 10.8 g/10 min, 10.9 g/10 min, 11.0 g/10 min, 11.1 g/10 min, 11.2 g/10 min, 11.3 g/10 min, 11.4 g/10 min, 11.5 g/10 min, 11.6 g/10 min, 11.7 g/10 min, 11.8 g/10 min, 11.9 g/10 min, 12.0 g/10mn, 12.1 g/10 min, 12.2 g/10 min, 12.3 g/10 min, 12.4 g/10 min, 12.5 g/10 min, 12.6 g/10 min, 12.7 g/10 min, 12.8 g/10 min, 12.9 g/10 min, 13.0 g/10 min, 13.1 g/10 min, 13.2 g/10 min, 13.3 g/10 min, 13.4 g/10 min, 13.5 g/10 min, 13.6 g/10 min, 13.7 g/10 min, 13.8 g/10 min, 13.9 g/10 min, 14.0 g/10 min, 14.1 g/10 min, 14.2 g/10 min, 14.3 g/10 min, 14.4 g/10 min, 14.5 g/10 min, 14.6 g/10 min, 14.7 g/10 min, 14.8 g/10 min, 14.9 g/10 min, 15.0 g/10 min, 15.1 g/10 min, 15.2 g/10 min, 15.3 g/10 min, 15.4 g/10 min, 15.5 g/10 min, 15.6 g/10 min, 15.7 g/10 min, 15.8 g/10 min, 15.9 g/10 min, 16.0 g/10 min, 16.1 g/10 min, 16.2 g/10 min, 16.3 g/10 min, 16.4 g/10 min, 16.5 g/10 min, 16.6 g/10 min, 16.7 g/10 min, 16.8 g/10 min, 16.9 g/10 min, 17.0 g/10 min, 17.1 g/10 min, 17.2 g/10 min, 17.3 g/10 min, 17.4 g/10 min, 17.5 g/10 min, 17.6 g/10 min, 17.7 g/10 min, 17.8 g/10 min, 17.9 g/10 min, 18.0 g/10 min, 18.1 g/10 min, 18.2 g/10 min, 18.3 g/10 min, 18.4 g/10 min,

18.5 g/10 min, 18.6 g/10 min, 18.7 g/10 min, 18.8 g/10 min, 18.9 g/10 min, 19.0 g/10 min, 19.1 g/10 min, 19.2 g/10 min, 19.3 g/10 min, 19.4 g/10 min, 19.5 g/10 min, 19.6 g/10 min, 19.7 g/10 min, 19.8 g/10 min, 19.9 g/10 min, and 20.0 g/10 min, as per ISO 1133. In particular embodiments, the HDPE may have an MFR at 190 °C and 5 kg of from 0.5 g/10 min to 5 g/10 min.

[0028] In certain instances, the HDPE may have a MFR at 190 °C and 2.16 kg of from 0.1 g/10 min to 5.0 g/10 min, as per ISO 1133, or at least, equal to, and/or between any two of 0.1 g/10 min, 0.2 g/10 min, 0.3 g/10 min, 0.4 g/10 min, 0.5 g/10 min, 0.6 g/10 min, 0.7 g/10 min, 0.8 g/10 min, 0.9 g/10 min, 1.0 g/10 min, 1.1 g/10 min, 1.2 g/10 min, 1.3 g/10 min, 1.4 g/10 min,

1.5 g/10 min, 1.6 g/10 min, 1.7 g/10 min, 1.8 g/10 min, 1.9 g/10 min, and 2.0 g/10 min, 2.1 g/10 min, 2.2 g/10 min, 2.3 g/10 min, 2.4 g/10 min, 2.5 g/10 min, 2.6 g/10 min, 2.7 g/10 min,

2.8 g/10 min, 2.9 g/10 min, 3.0 g/10 min, 3.1 g/10 min, 3.2 g/10 min, 3.3 g/10 min, 3.4 g/10 min, 3.5 g/10 min, 3.6 g/10 min, 3.7 g/10 min, 3.8 g/10 min, 3.9 g/10 min, 4.0 g/10 min, 4.1 g/10 min, 4.2 g/10 min, 4.3 g/10 min, 4.4 g/10 min, 4.5 g/10 min, 4.6 g/10 min, 4.7 g/10 min,

4.8 g/10 min, 4.9 g/10 min and 5.0 g/10 min.

[0029] In particular embodiments, the HDPE may have a MFR at 190 °C and 21.6 kg of from 10 g/10 min to 35 g/10 min, as per ISO 1133, or at least, equal to, and/or between any two of 10 g/10 min, 11 g/10 min, 12 g/10 min, 13 g/10 min, 14 g/10 min, 15 g/10 min, 16 g/10 min,

17 g/10 min, 18 g/10 min, 19 g/10 min, and 20 g/10 min, 21 g/10 min, 22 g/10 min, 23 g/10 min, 24 g/10 min, 25 g/10 min, 26 g/10 min, 27 g/10 min, 28 g/10 min, 29 g/10 min, 30 g/10 min, 31 g/10 min, 32 g/10 min, 33 g/10 min, 34 g/10 min, and 35 g/10 min. [0030] The HDPE component may have a poly dispersity index (PDI = Mw/Mn) of from 2 to 25 as determined by high temperature gel permeation chromatography, or at least, equal to, and/or between any two of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, and 25. In certain applications, the PDI may range from 13 to 20, as determined by high temperature gel permeation chromatography.

[0031] Tensile modulus of the HDPE can be from 800 MPa to 1300 MPa, or at least, equal to, and/or between any two of 800 MPa, 850 MPa, 900 MPa, 950 MPa, 1000 MPa, 1050 MPa, 1100 MPa, 1150 MPa, 1200 MPa, 1250 MPa and 1300 MPa, as measured by ISO 527. Tensile strength at yield of the HDPE can be from 20 MPa to 40 MPa, or at least, equal to, and/or between any two of 20 MPa, 25 MPa, 30 MPa, 35 MPa, and 40 MPa, as measured by ISO 527. [0032] The Izod notched impact strength of the HDPE component at -30 °C can be from 3 kJ/m² to 6 kJ/m² or at least, equal to, and/or between any two of 3 kJ/m², 4 kJ/m², 5 kJ/m², and 6 kJ/m². The Izod notched impact strength of the HDPE component at 23 °C can be from 10 kJ/m² to 30 kJ/m² or at least, equal to, and/or between any two of 10 kJ/m², 11 kJ/m², 12 kJ/m², 13 kJ/m², 14 kJ/m², 15 kJ/m², 16 kJ/m², 17 kJ/m², 18 kJ/m², 19 kJ/m², 20 kJ/m², 21 kJ/m², 22 kJ/m², 23 kJ/m², 24 kJ/m², 25 kJ/m², 26 kJ/m², 27 kJ/m², 28 kJ/m², 29 kJ/m², and 30 kJ/m² as measured by ISO 180.

[0033] The HDPE component, as described above, is used as a polymer blend in combination with one or more different optics-enhancing additives used to provide the increased transparency and/or reduced haze. The lack of transparency and/or haze of HDPE is the result of light scattering that results in the opaque or translucent appearance of the HDPE. This is largely attributed to the large amount of crystalline spherulites present in the HDPE material, which scatter the light.

[0034] The optics-enhancing additives may include one or more polymeric additives that are insoluble or immiscible with the HDPE. These polymeric additives may be used in combination with a further optics-enhancing additive of a clarifying and/or nucleating agent. The addition of these additives is believed to reduce the size and/or shape of the crystalline spherulites in the HDPE composition when the melt blend begins to crystallize, such as during the molding of the HDPE article, thereby leading to the lowering of percentage crystallinity and/or the lowering of size of crystalline spherulites and/or the alteration of the shape of crystalline spherulites. This is true even though the additives are added during melt mixing of the HDPE during the extrusion process. [0035] These optics-enhancing additives may be selected and used in amounts so that the processability, flow properties, and mechanical properties remain mainly unaffected, while the optical properties are improved. This is important because in addition to the optics-enhancing additives reducing the size and/or altering the shape of the crystalline spherulites, the optic enhancing additives may also lower the overall percentage crystallinity of the HDPE composition by 30% to 80% of its original value without the use of the optics-enhancing additives. In particular embodiments, the optic-enhancing additives may lower the overall percentage crystallinity of the HDPE composition by at least equal to, and/or between any two of 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, and 80% of its original value without the use of the optics-enhancing additives. While a reduction in crystallinity may increase the transparency and/or reduce haze of the HDPE composition, such reduction in crystallinity can also negatively impact its processability, flow properties, and mechanical properties. Therefore, a careful balance must be maintained so that the decrease in crystallinity of the HDPE composition does not significantly alter its processability and flow properties, and perhaps more importantly, its final mechanical properties, such as its ESCR performance, which is critical for the HDPE composition being useful in commercial applications.

[0036] The optic-enhancing polymeric additive is insoluble or immiscible with the HDPE material. As used herein, the terms “insoluble” or “immiscible” and variations of these terms may be used interchangeably and refer to the characteristic of the polymeric additive as not dissolving or not being capable of homogeneously mixing with the HDPE material under the processing conditions used in forming the HDPE composition. The insoluble or immiscible polymeric additives form a domain morphology within a continuous matrix of HDPE, in transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) analyses. As a result, these polymeric additives remain dispersed within the HDPE matrix as discrete domains that affect or alter the formation of the crystalline spherulite structures within the HDPE material.

[0037] This insolubility or immiscibility of the polymeric additive with the HDPE material is the result of the polymeric additive having a comonomer that is distinctly different from the ethylene monomers of the HDPE. Such comonomers of the polymeric additive may contain functional groups of one or more of an OH group, an ionic group, a norbornyl group, an ether (ROR') group, a cyclic olefin group, and a cyclic amide group (e.g., polyvinylpyrrolidone [PVP]), etc. The amount of comonomer present in the polymer additives may range from 1 mole % to 50 mole %. In particular embodiments, the amount of the comonomer present in the polymeric additive may be at least, equal to, and/or between any two of 1 mole%, 2 mole %, 3 mole%, 4 mole%, 5 mole %, 6 mole%, 7 mole%, 8 mole %, 9 mole%, 10 mole%, 11 mole%, 12 mole %, 13 mole%, 14 mole%, 15 mole %, 16 mole%, 17 mole%, 18 mole %, 19 mole%, 20 mole%, 21 mole%, 22 mole %, 23 mole%, 24 mole%, 25 mole %, 26 mole%, 27 mole%, 28 mole %, 29 mole%, 30 mole%, 31 mole%, 32 mole %, 33 mole%, 34 mole%, 35 mole %, 36 mole%, 37 mole%, 38 mole %, 39 mole%, 40 mole%, 41 mole%, 42 mole %, 43 mole%, 44 mole%, 45 mole %, 46 mole%, 47 mole%, 48 mole %, 49 mole% and 50 mole%.

[0038] The insoluble or immiscible polymeric additive, which may be any one or a combination of two or more different insoluble or immiscible polymeric additive materials, may be used in an amount of from 0.1 wt. % to 5 wt. % by total weight of the HD PE composition. In particular embodiments, the amount of the polymeric additive used may be at least, equal to, and/or between any two of 0.1 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, 1.0 wt.%, 1.1 wt.%, 1.2 wt.%, 1.3 wt.%, 1.4 wt.%, 1.5 wt.%, 1.6 wt.%, 1.7 wt.%, 1.8 wt.%, 1.9 wt.%, 2.0 wt.%, 2.1 wt.%, 2.2 wt.%, 2.3 wt.%, 2.4 wt.%, 2.5 wt.%, 2.6 wt.%, 2.7 wt.%, 2.8 wt.%, 2.9 wt.%, 3.0 wt.%, 3.1 wt.%, 3.2 wt.%, 3.3 wt.%, 3.4 wt.%, 3.5 wt.%, 3.6 wt.%, 3.7 wt.%, 3.8 wt.%, 3.9 wt.%, 4.0 wt.%, 4.1 wt.%, 4.2 wt.%, 4.3 wt.%, 4.4 wt.%, 4.5 wt.%, 4.6 wt.%, 4.7 wt.%, 4.8 wt.%, 4.9 wt.%, and 5.0 wt.% by total weight of the HDPE composition.

[0039] Non-limiting examples of suitable insoluble or immiscible polymers may include such polymers as low molecular weight polyethylene glycol (PEG), high molecular weight polyethylene glycol (PEG), silyated polyethylene glycol (PEG), ethylene vinyl alcohol (EVOH) having an ethylene content of from 25 mol% to 50 mol%, ethylene vinyl acetate (EVA), polyvinylpyrrolidone (PVP), ionomeric polyethylene, cyclic olefin copolymers (COC), sytrenic copolymer, etc. Combinations of these materials may also be used.

[0040] In particular embodiments, the low molecular weight PEG used for the immiscible polymeric additive may be that having an average molecular weight (Mw) of from 600 to 2000, as determined by high temperature gel permeation chromatography. In particular embodiments, the low molecular weight PEG may have an average molecular weight (Mw) of from at least, equal to, and/or between any two molecular weights of 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, and 2000. [0041] The high molecular weight PEG used for the immiscible polymeric additive may be that having an average molecular weight (Mw) of from 4000 or higher, as determined by high temperature gel permeation chromatography. In particular embodiments, the high molecular weight PEG may have an average molecular weight (Mw) of from at least, equal to, and/or between any two molecular weights of 4000, 4500, 5000, 5500, 6000, 6500, 7000, 7500, 8000, 8500, 9000, 9500, 10,000, 10,500, 11,000, 11,500, 12,000, 12,500, 13,000, 13,500, 14,000, 14,500, 15,000, 15,500, 16,000, 16,500, 17,000, 17,500, 18,000, 18,500, 19,000, 19,500, and 20,000.

[0042] The silyated PEG used for the immiscible polymeric additive is that which has silyl groups at the ends of the PEG polymer. Such silyl groups may include trimethoxy, triethoxy, methyldimethoxy, methyldiethoxy, and others. The silylated PEG may be that having an average molecular weight (Mw) of from 600 to 4000, as determined by high temperature gel permeation chromatography. In particular embodiments, the silyated PEG may have an average molecular weight (Mw) of from at least, equal to, and/or between any two molecular weights of 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500, 2600, 2700, 2800, 2900, 3000, 3100, 3200, 3300, 3400, 3500, 3600, 3700, 3800, 3900, and 4000.

[0043] The ethylene-vinyl alcohol (EVOH) is that having from 25 mol% to 50 mol% ethylene. EVOH is more polar than polyethylene due to the polar OH groups. Accordingly, the more ethylene content of the EVOH the lower its polarity. The presence of more ethylene should therefore result in better dispersion within the HDPE. The polarity of the material can be characterized by the water contact angle of film/substrate made of the material. The higher the polarity, the lower the water contact angle and vice versa. Homopolymers and/or copolymers of polyethylene typically have a water contact angle of from 110° to 130°. In contrast, EVOH materials with an ethylene content of from 25 mol% to 50 mol% typically have a water contact angle of from 60° to 90°. In particular embodiments, the EVOH may have an ethylene content of from at least, equal to, and/or between any two 25 mol%, 30 mol%, 35 mol%, 40 mol%, 45 mol%, and 50 mol%. The EVOH may have an average molecular weight (Mw) of from 100,000 to 300,000, as determined by high temperature gel permeation chromatography. In particular embodiments, the EVOH may have an average molecular weight (Mw) of from at least, equal to, and/or between any two molecular weights of 1,000,000, 1,100,000, 1,200,000, 1,300,000, 1,400,000, 1,500,000, 1,600,000, 1,700,000, 1,800,000, 1,900,000, 2,000,000, 2,100,000, 2,200,000, 2,300,000, 2,400,000, 2,500,000, 2,600,000, 2,700,000, 2,800,000, 2,900,000, and 3,000,000. Moreover, the EVOH may have a polydispersity (PDI) of from 1.8 to 4.0. In particular embodiments, the EVOH may have a PDI of at least, equal to, and/or between any two values of 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9. 3.0. 3.1 3.2, 3.3, 3.4, 3.5, 3.6, 3.7 3.8, 3.9, and 4.0.

[0044] The polyvinylpyrrolidone (PVP) may be that having an average molecular weight (Mw) of from 5,000 to 40,000, as determined by high temperature gel permeation chromatography. In particular embodiments, the PVP may have an average molecular weight (Mw) of from at least, equal to, and/or between any two molecular weights of 5000, 6000, 7000, 8000, 9000, 10,000, 11,000, 12,000, 13,000, 14,000, 15,000, 16,000, 17,000, 18,000, 19,000, 20,000, 21,000, 22,000, 23,000, 24,000, 25,000, 26,000, 27,000, 28,000, 29,000, 30,000, 31,000, 32,000, 33,000, 34,000, 35,000, 36,000, 37,000, 38,000, 39,000, and 40,000.

[0045] The ionomeric polyethylene used as the optics-enhancing additive is that which is insoluble or immiscible in the HDPE. The ionomeric polyethylene used may be comprised of copolymers of ethylene and ionic compounds of carboxylic acid and/or sulphonic acid monomers. The carboxylic acid monomer may be those a, b-ethylenically unsaturated carboxylic acid group containing monomers having from 3 to 8 carbon atoms, and their combinations. Such ionomeric polyethylene materials incorporating such carboxylic acid monomers include those described in U.S. Patent No. 3,264,272, which is hereby incorporated herein by reference for all purposes. In particular, those carboxylic acid monomers of acrylic acid, methylacrylic acid, and/or an ethylacrylic acid, and combinations of these and others, may be particularly useful.

[0046] The ionic groups of the immiscible ionomeric polyethylene are distributed throughout the ionomeric polyethylene copolymer and may be randomly distributed along the polymer chain. The ionic groups (e.g., carboxylic acid and/or sulphonic acid groups) may be present in the ionomeric polyethylene in an amount of from 50 mol%, 45 mol%, 40 mol%, 35 mol%, 30 mol%, 25 mol%, 20 mol%, 15 mol%, 10 mol%, 5 mol%, 1 mol%, 0.5 mol % or less. In particular embodiments, the ionic groups may be present in the ionomeric polyethylene in an amount at least, equal to, and/or between any two of 0.2 mol%, 0.3 mol%, 0.4 mol%, 0.5 mol%, 1 mol%, 5 mol%, 10 mol%, 15 mol%, 20 mol%, 25 mol%, 30 mol%, 35 mol%, 40 mol%, 45 mol%, and 50 mol%. In more particular embodiments, the ionic groups are present in the ionomeric polyethylene in an amount at least, equal to, and/or between any two of 0.2 mol%, 0.3 mol%, 0.4 mol%, 0.5 mol%, 1 mol%, 5 mol%, 10 mol%, 15 mol%, 20 mol%, and 25 mol%. And still more particularly, the ionic groups may be present in the ionomeric polyethylene in an amount at least, equal to, and/or between any two of 1 mol%, 2 mol%, 3 mol%, 4 mol%, 5 mol%, 6 mol%, 7 mol%, 8 mol%, 9 mol%, 10 mol%, 11 mol%, 12 mol%, 13 mol%, 14 mol% and 15 mol%.

[0047] The immiscible ionomeric polyethylene used for the optics-enhancing additive will typically contain metal counter ions that neutralize all or some portion of the ionic groups of carboxylic and/or sulphonic acid. The metal counter ions may comprise at least one of mono or divalent metal salts that may be distributed throughout the polymer. Non-limiting examples of such metal counter ions include Li, Na, K, Zn, Ca, Mg, Pb and Sn, and combinations of these. These may be used in an amount to provide from 10%, 20%, 30%, 40%, 50% or more neutralization of the carboxylic acid and/or sulphonic acid groups of the ionomeric polyethylene. In particular embodiments, the metal counter ions may be used in an amount at least, equal to, and/or between any two of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100% neutralization of the carboxylic acid and/or sulphonic acid groups of the ionomeric polyethylene.

[0048] The immiscible ionomeric polyethylene optics-enhancing component may have a weight average molecular weight (Mw) of from 3000 to 60,000 with respect to polystyrene standard or at least, equal to, and/or between any two molecular weights of, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10,000, 11,000, 12,000, 13,000, 14,000, 15,000, 16,000, 17,000, 18,000, 19,000, 20,000, 21,000, 22,000, 23,000, 24,000, 25,000, 26,000, 27,000, 28,000, 29,000, 30,000, 31,000, 32,000, 33,000, 34,000, 35,000, 36,000, 37,000, 38,000, 39,000, 40,000, 41,000, 42,000, 43,000, 44,000, 45,000, 46,000, 47,000, 48,000, 49,000, 50,000, 51,000, 52,000, 53,000, 54,000, 55,000, 56,000, 57,000, 58,000, 59,000 and 60,000. In certain embodiments, the weight average Mw of the ionomeric polyethylene is from 5,000 to 20,000, 30,000, or 40,000.

[0049] The immiscible ionomeric polyethylene optics-enhancing component may have a density from 945 kg/m³ to 965 kg/m³, or at least, equal to, and/or between any two of 945 kg/m³, 950 kg/m³, 955 kg/m³, 960 kg/m³, and 965 kg/m³. The ionomeric polyethylene component of the polymer blend may have a melt flow rate at 190 °C and with a load of 2.16 Kg from 0.5 dg/min to 10 dg/min.

[0050] The immiscible ionomeric polyethylene may be a preformed ionomeric polyethylene, with or without neutralization by metal counter ions. Such ionomeric polyethylene may be that prepared in a reactor by copolymerizing ethylene with the ionic groups or ionic group precursors through conventional polymerization techniques. A non-limiting example of a suitable commercially available ionomeric polyethylene is that available as SURLYN^®- PC350, from E.I. du Pont de Nemours and Company, Inc., Wilmington, DE.

[0051] In other instances, the ionomeric polyethylene may be formed by grafting ionic compounds, such as carboxylic acid and/or sulphonic acid, to preexisting polyethylene polymers. Such ionomeric polyethylene formed by grafting techniques may be pre-formed, as well, and used in a polymer blend in conjunction with non-ionomeric HDPE of the polymer blend. Graft polymerization may be carried out by ionizing radiation, UV radiation, and chemical initiators. In certain applications, grafting may be carried out in situ during extrusion of non-ionomeric HDPE to form the desired ionomeric polyethylene content of the final HDPE product.

[0052] The ionic groups may be the same or different for the immiscible ionomeric polyethylene used (e.g., ethylene copolymerized with carboxylic acid and sulphonic acid, ethylene copolymerized with acrylic acid and methacrylic acid, etc.). In some embodiments, different ionomeric polyethylene copolymers having different ionic groups may be used in combination with one another (e.g., mixture of ethylene/carboxylic acid copolymers and ethylene/sulphonic acid copolymers).

[0053] The cyclic olefin copolymers used as the optics-enhancing additive may be copolymers of ethylene and norbornene, prepared via metathesis ring opening polymerization, using a metallocene catalyst. The norbornene content in the copolymer may vary from 60 wt.% to 90 wt.% and the glass transition temperature may vary from 50 °C to 200 °C. A non-limiting example of a suitable commercially available cyclic olefin copolymers is that available as TOPAS^®-5013 from Topas Advanced Polymers, Inc., Florence, Kentucky, USA.

[0054] The immiscible styrenic block polymers used as the optics-enhancing additive may be hydrogenated styrene-olefin random block polymers and may include Ci to C4 olefins. Particularly useful for the olefins of the styrene-olefin random block polymer are ethylene, propylene, butylene, isobutylene, and combinations of these or other olefins. The styrenic block polymers include those having an average molecular weight (Mw) of from 50,000 to 600,000 as measured by GPC against a polystyrene standard. In particular embodiments, the styrenic block polymer may have an average molecular weight (Mw) of from at least, equal to, and/or between any two molecular weights of 50,000, 55,000, 60,000, 65,000, 70,000, 75,000, 80,000, 85,000, 90,000, 100,000, 200,000, 300,000, 400,000, 500,000, and 600,000.

[0055] The styrene content of the styrenic block polymers may range from 10 wt.% to 70 wt.% by total weight of the styrenic block polymer, or may be from at least, equal to, and/or between any two of 10 wt.%, 11 wt.%, 12 wt.%, 13 wt.%, 14 wt.%, and 15 wt.%, 16 wt.%, 17 wt.%, 18 wt.%, 19 wt.%, 20 wt.%, 21 wt.%, 22 wt.%, 23 wt.%, 24 wt.%, 25 wt.%, 26 wt.%, 27 wt.%, 28 wt.%, 29 wt.%, 30 wt.%, 31 wt.%, 32 wt.%, 33 wt.%, 34 wt.%, 35 wt.%, 36 wt.%, 37 wt.%, 38 wt.%, 39 wt.%, 40 wt.%, 41 wt.%, 42 wt.%, 43 wt.%, 44 wt.%, and 45 wt.%, 46 wt.%, 47 wt.%, 48 wt.%, 49 wt.%, 50 wt.%, 51 wt.%, 52 wt.%, 53 wt.%, 54 wt.%, and 55 wt.%, 56 wt.%, 57 wt.%, 58 wt.%, 59 wt.%, 60 wt.%, 61 wt.%, 62 wt.%, 63 wt.%, 64 wt.%, and 65 wt.%, 66 wt.%, 67 wt.%, 68 wt.%, 69 wt.%, and 70 wt.% by total weight of the styrenic block polymer.

[0056] A non-limiting example of a suitable commercially available styrenic block polymer for use as the optics-enhancing additive is that sold as SEPTON™ 2104, available from Kuraray Co., Ltd., which is a styrene ethylene propylene styrene block polymer having a styrene content of 65 wt.%, a MFR at 230 °C and 2.16 kg of 0.4 g/min, and an average Mw of approximately 80,000.

[0057] The optics-enhancing additive of a clarifying and/or nucleating agent may be used in combination with those insoluble or immiscible polymeric additives discussed above. Nucleating agents may be considered as those additives that are added to polymers to facilitate crystal growth in the polymer melt. Those nucleating agents that can be classified as clarifying agents also facilitate crystal growth, but the crystal growth is reduced in comparison to nucleating agents that can be classified as non-clarifying nucleating agents, leading to a reduction in the size and shape of the crystalline spherulite of semi-crystalline polymers. As used herein, unless otherwise specified, the term “clarifying agent” and similar expressions are meant to encompass those nucleating agent compounds that facilitate crystal growth where the crystal growth results in a reduced crystalline spherulite size from those that would result without the clarifying agent. Where the term “nucleating agent” and similar expressions are used, unless otherwise specified, it is meant to include those compounds that form nuclei for facilitating crystal growth in the polymer melt with or without reducing the size of the crystalline spherulites. Such nucleating agents would broadly cover clarifying agents, as well. The expression “non-clarifying nucleating agent” and similar expressions is meant to encompass those nucleating agents that do not normally reduce the size of the crystalline spherulites or that would not be classified as a clarifying agent.

[0058] While clarifying and/or nucleating agents have been commonly used with such materials as polypropylene (PP), polyethylene terephthalate (PET), nylon, etc., they have not been used commercially with polyethylene. This is because polyethylene has a very high crystallization rate and kinetics. The rate of crystallization is difficult to control compared to other polymers. Furthermore, HDPE has a relatively high percentage crystallinity compared to these other polymers, such that the use of nucleating agents is not necessary.

[0059] When used in specific amounts in forming the HDPE compositions described herein, the clarifying and/or nucleating agents have been shown to increase the transparency and/or reduce haze in the HDPE compositions without significantly affecting the crystallinity of the HDPE composition to a degree that the desired flow characteristics, processability, and mechanical properties are significantly altered. This is particularly true when used in combination with the insoluble or immiscible polymeric additives, as discussed previously, where they may have a synergistic effect. The amount of the clarifying and/or nucleating agents may range from 100 ppm to 200 ppm by total weight of the HDPE composition. In particular embodiments, the clarifying and/or nucleating agent may be used in an amount of from at least, equal to, and/or between any two of 100 ppm, 101 ppm, 102 ppm, 103 ppm, 104 ppm, 105 ppm, 106 ppm, 107 ppm, 108 ppm, 109 ppm, 110 ppm, 111 ppm, 112 ppm, 113 ppm, 114 ppm, 115 ppm, 116 ppm, 117 ppm, 118 ppm, 119 ppm, 120 ppm, 121 ppm, 122 ppm, 123 ppm, 124 ppm, 125 ppm, 126 ppm, 127 ppm, 128 ppm, 129 ppm, 130 ppm, 131 ppm, 132 ppm, 133 ppm, 134 ppm, 135 ppm, 136 ppm, 137 ppm, 138 ppm, 139 ppm, 140 ppm, 141 ppm, 142 ppm, 143 ppm, 144 ppm, 145 ppm, 146 ppm, 147 ppm, 148 ppm, 149 ppm, 150 ppm, 151 ppm, 152 ppm, 153 ppm, 154 ppm, 155 ppm, 156 ppm, 157 ppm, 158 ppm, 159 ppm, 160 ppm, 161 ppm, 162 ppm, 163 ppm, 164 ppm, 165 ppm, 166 ppm, 167 ppm, 168 ppm, 169 ppm, 170 ppm, 171 ppm, 172 ppm, 173 ppm, 174 ppm, 175 ppm, 176 ppm, 177 ppm, 178 ppm, 179 ppm, 180 ppm, 181 ppm, 182 ppm, 183 ppm, 184 ppm, 185 ppm, 186 ppm, 187 ppm, 188 ppm, 189 ppm, 190 ppm, 191 ppm, 192 ppm, 193 ppm, 194 ppm, 195 ppm, 196 ppm, 197 ppm, 198 ppm, 199 ppm, and 200 ppm by total weight of the HDPE composition.

[0060] Non-limiting examples of suitable nucleating agents include calcium salts of dicarboxylic acid, metal salts of cyclohexane dicarboxylic acid, bisamide, lithium carbonate, benzoic acid, inorganic oxides, nano-zinc oxides, talc, clays, powdered polymeric agents such as polyphenylene oxide, polyvinylenedifluoride, polycarbonate, polycarbonate-siloxane copolymer, cross-linked polycarbonate, polyetherimide, polyamide, ethylene propylene diene monomer, and polyoxymethylene. A non-limiting example of a suitable commercially available nucleating agent is that available as HYPERFORM™ HPN-20E, available from Milliken & Company, which is a calcium salt of cyclohexane dicarboxylic acid. [0061] Non-limiting examples of suitable clarifying agents include sorbitol derivatives,

1.2.3.4-bis-dibenzylidene sorbitol (DBS), l,2,3,4-bis-(p-methoxybenzylidene sorbitol) (DOS),

1.2.3.4-bis-(3,4-dimethylbenzylidene sorbitol) (MBDS), and l,3:2,4-di(3,4- dimethylbenzylidene) sorbitol (DMDBS).

[0062] The polyethylene compositions can further include at least one additional optional or secondary additive, as distinguished from the optics-enhancing polymeric additives and clarifying and/or nucleating agents discussed above. Such optional or secondary additives may be those that do not necessarily impact or increase the transparency or haze of the final product. Non-limiting examples of additional optional or secondary additives include a heat conductive agent, a tie agent, an antiblocking agent, an antistatic agent, an antioxidant, a neutralizing agent, an acid scavenger, a blowing agent, a dye, a flame retardant agent, a filler (hard or soft), an impact modifier, a mold release agent, an oil, another polymer, a pigment, a processing agent, a reinforcing agent, a stabilizer (including light stabilizers), an UV resistance agent, a slip agent, a flow modifying agent, and combinations thereof.

[0063] In some instances, a heat conductive additive is present in the polymer blend in an amount of at least, equal to, and/or between any two of 0.01 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, and 1.0 wt. % by total weight of the polymer blend. Non-limiting examples of heat conductive additive include, aluminum oxide, titanium dioxide, graphitic compounds, graphenes, boron nitride, aluminum nitride, zinc oxide [0064] In certain aspects, a tie molecule is present in the polymer blend in amount of at least, equal to, and/or between any two of 0.01 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, and 1.0 wt. % by total weight of the polymer blend. Non- limiting examples of tie molecules include, linear low-density polyethylene, low-density polyethylene, medium density polyethylene.

[0065] In some embodiments, a filler is present in the polymer blend in amount of at least, equal to, and/or between any two of 0.01 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, 1.0 wt. %, 2.0 wt. %, 3.0 wt. %, 4.0 wt. %, 5.0 wt. %, 6.0 wt. %, 7.0 wt. %, 8.0 wt. %, 9.0 wt. %, 10.0 wt. %, 20.0 wt. %, 30.0 wt. % by total weight of the polymer blend. The filler can be a hard filler. Non-limiting examples of hard filler include, inorganic particulate fillers such as silica, calcium carbonate, inorganic layered fillers such as clays, mica. The filler can be a soft filler. Non-limiting examples of soft filler include, immiscible particulate elastomeric/polymeric resins. The filler can also be a hollow filler. Non- limiting examples of hollow filler include, glass microspheres, plastic microspheres, ceramic microspheres such as cenospheres made up of alumino silicate microspheres, metallic microspheres made up of aluminum and copper/silver microspheres, phenolic microspheres. [0066] In certain aspects, a light stabilizer is present in the polymer blend in an amount of at least, equal to, and/or between any two of 0.01 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, and 1.0 wt. % by total weight of the polymer blend. The light stabilizer can be a hindered amine light stabilizer. The term “hindered amine light stabilizer” refers to a class of amine compounds having certain light stabilizing properties. Non-limiting examples, of hindered amine light stabilizers (HALS) include 1-cyclohexyloxy- 2,2,6,6-tetramethyl-4-octadecylaminopiperidine; bis(2,2,6,6-tetramethylpiperidin-4-yl) sebacate; bis(l-acetoxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate; bis(l,2,2,6,6- pentamethylpiperidin-4-yl) sebacate; bis(l-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate; bis(l-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate; bis(l-acyl-2, 2,6,6- tetramethylpiperidin-4-yl) sebacate; bis(l,2,2,6,6-pentamethyl-4-piperidyl) n-butyl-3,5-di- tert-butyl-4-hydroxybenzyl malonate; 2,4-bis[(l-cyclohexyloxy-2,2,6,6-tetramethylpiperidin- 4-yl)butylamino]-6-(2-hydroxyethyl amino-s-triazine; bis(l-cyclohexyloxy-2, 2,6,6- tetramethylpiperidin-4-yl) adipate; 2,4-bis[(l-cyclohexyloxy-2,2,6,6-piperidin-4- yl)butylamino]-6-chloro-s-triazine; l-(2-hydroxy-2-methylpropoxy)-4-hydroxy-2,2,6,6- tetramethylpiperidine; l-(2-hydroxy-2-methylpropoxy)-4-oxo-2,2,6,6-tetramethylpiperidine; l-(2-hydroxy-2-methyl propoxy)-4-octadecanoyloxy-2,2,6,6-tetramethyl piperidine; bis(l-(2- hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl) sebacate;bis(l-(2-hydroxy-2- methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl) adipate; 2, 4-bis{N-[l-(2 -hydroxyl- methyl propoxy)-2,2,6,6-tetramethylpiperidin-4-yl]-N-butylamino}-6-(2- hydroxyethylamino)-s-triazine; 4-benzoyl-2,2,6,6-tetramethylpiperidine; di-(l,2,2,6,6- pentamethylpiperidin-4-yl) p-methoxybenzylidenemalonate ; 2 ,2 , 6 ,6-tetr amethylpiperidin-4-yl octadecanoate; bis(l-octyloxy-2,2,6,6-tetramethylpiperidyl) succinate; 1,2,2,6,6-pentamethyl- 4-aminopiperidine; 2-undecyl-7,7,9,9-tetramethyl-l-oxa-3,8-diaza-4-oxo-spiro[4,5]decane; tris(2,2,6,6-tetramethyl-4-piperidyl) nitrilotriacetate; tris(2-hydroxy-3-(amino-(2, 2,6,6- tetramethylpiperidin-4-yl)propyl) nitrilotriacetate; tetrakis(2,2,6,6-tetramethyl-4-piperidyl)- 1,2,3,4-butane-tetracarboxylate; tetrakis(l, 2,2,6, 6-pentamethyl-4-piperidyl)-l, 2,3, 4-butane- tetracarboxylate; 1 , 1 '-(1 ,2-ethanediyl)-bis(3,3,5,5-tetramethylpiperazinone); 3-n-octyl-

7,7,9,9-tetramethyl-l,3,8-triazaspiro[4.5]decan-2,4-dione; 8-acetyl-3-dodecyl-7,7,9,9- tetramethyl-l,3,8-triazaspiro[4.5]decane-2,4-dione; 3-dodecyl-l -(2,2,6, 6-tetramethyl-4- piperidyl)pyrrolidin-2,5-dione; 3-dodecyl-l-(l,2,2,6,6-pentamethyl-4-piperidyl)pyrrolidine- 2,5-dione; N,N'-bis-formyl-N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine; reaction product of 2,4-bis[(l-cyclohexyloxy-2,2,6,6-piperidin-4-yl)butylamino]-6-chloro-s- triazine with N,N'-bis(3-aminopropyl)ethylenediamine);condensate of 1 -(2 -hydroxy ethyl)- 2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid; condensate of N, N'-bis(2, 2,6,6- tetramethyl-4-piperidyl)-hexamethylenediamine and 4-tert-octylamino-2,6-dichloro- 1,3,5- triazine; condensate of N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)-hexamethylenediamine and 4-cyclohexylamino-2,6-dichloro-l,3,5-triazine; condensate of N,N'-bis-(2,2,6,6-tetramethyl- 4-piperidyl)hexamethylenediamine and 4-morpholino-2,6-dichloro-l,3,5-triazine; condensate of N,N'-bis-(l ,2,2,6, 6-pentamethyl-4-piperidyl)hexamethylenediamine and 4-morpholino-2,6- dichloro-l,3,5-triazine; condensate of 2-chloro-4,6-bis(4-n-butylamino-2,2,6,6-tetramethyl piperidyl)-l,3,5-triazine and l,2-bis(3-aminopropylamino)ethane; condensate of 2-chloro-4,6- di-(4-n-butylamino-l,2,2,6,6-pentamethylpiperidyl)-l,3,5-triazine and l,2-bis-(3- aminopropylamino)ethane; a reaction product of 7,7,9,9-tetramethyl-2-cycloundecyl-l-oxa- 3,8-diaza-4-oxospiro[4,5]decane and epichlorohydrin; poly[methyl, (3-oxy-(2, 2,6,6- tetramethylpiperidin-4-yl)propyl)]siloxane, CAS#182635-99-0; reaction product of maleic acid anhydride-C18-C22-a-olefin-copolymer with 2,2,6,6-tetramethyl-4-aminopiperidine; oligomeric condensate of 4,4'-hexamethylenebis(amino-2,2,6,6-tetramethylpiperidine) and 2,4-dichloro-6-[(2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-s-triazine end-capped with 2- chloro-4,6-bis(dibutylamino)-s-triazine; oligomeric condensate of 4,4'- hexamethylenebis(amino-l,2,2,6,6-pentaamethylpiperidine) and 2,4-dichloro-6-[(l,2,2,6,6- pentaamethylpiperidin-4-yl)butylamino]-s-triazine end-capped with 2-chloro-4,6- bis(dibutylamino)-s-triazine; oligomeric condensate of 4,4'-hexamethylenebis(amino-l- propoxy-2,2,6,6-tetramethyl piperidine) and 2,4-dichloro-6-[(l-propoxy-2,2,6,6- tetramethylpiperidin-4-yl)butylamino]-s-triazine end-capped with 2-chloro-4,6- bis(dibutylamino)-s-triazine; oligomeric condensate of 4,4'-hexamethylenebis(amino-l- acyloxy-2,2,6,6-tetramethyl piperidine) and 2,4-dichloro-6-[(l-acyloxy-2,2,6,6- tetramethylpiperidin-4-yl)butylamino]-s-triazine end-capped with 2-chloro-4,6- bis(dibutylamino)-s-triazine; and product obtained by reacting (a) with (b) where (a) is product obtained by reacting l,2-bis(3-aminopropylamino)ethane with cyanuric chloride and (b) is (2,2,6,6-tetramethyl piperidin-4-yl)butylamine. Also included are the sterically hindered N-H, N-methyl, N-methoxy, N-hydroxy, N-propoxy, N-octyloxy, N-cyclohexyloxy, N-acyloxy and N-(2-hydroxy-2-methylpropoxy) analogues of any of the above-mentioned compounds. Non limiting examples of commercial light stabilizer are available from BASF under the trade name Uvinul® 4050H, 4077H, 4092H, 5062H, 5050H, 4092H, 4077H, 3026, 3027, 3028, 3029, 3033P, and 3034 or Tinuvin® 622.

[0067] Anti-static agents can be used to inhibit accumulation of dust on plastic articles. Antistatic agents can improve the electrical conductivity of the plastic compositions, and thus dissipate any surface charges, which develop during production and use. Thus, dust particles are less attracted to the surface of the plastic article, and dust accumulation is consequently reduced. In certain aspects of the present invention, the antistatic agent can be a glycerol monostearate. The polymer blend can include an anti-static agent in an amount of at least, equal to, and/or between any two 0.01 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, and 1 wt. % by total weight of the polymer blend.

[0068] A lubricant can be added to a polymer blend to improve the mold-making characteristics. The lubricant can be a low molecular compound from a group of fatty acids, fatty acid esters, wax ester, fatty alcohol ester, amide waxes, metal carboxylate, montanic acids, montanic acid ester, or such high molecular compounds, as paraffins or polyethylene waxes. In certain aspects of the present invention, the lubricant is a metal stearate. Non-limiting examples of metal stearates include zinc stearate, calcium stearate, lithium stearate or a combination thereof, preferably calcium stearate. The polymer blend can include a lubricant in an amount of at least, equal to, and/or between any two of 0.01 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, and 1 wt. % by total weight of the polymer blend.

[0069] An antioxidant can provide protection against polymer degradation during processing. Phosphites are known thermal oxidative stabilizing agents for polymers and other organic materials. The antioxidant can be a phosphite-based antioxidant. In certain aspects phosphite- antioxidants include, but are not limited to, triphenyl phosphite, diphenylalkyl phosphites, phenyldialkyl phosphites, tris(nonylphenyl)phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl)phosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite tristearyl sorbitol triphosphite, and tetrakis(2,4-di-tertbutylphenyl)-4,4'-biphenylene diphosphonite, bis(2,4-dicumylphenyl)pentaerythritol diphosphite. The polymer blend can include an antioxidant in an amount of at least, equal to, and/or between any two of 0.01 wt.%, 02 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, and 0.1 wt. % by total weight of the polymer blend. Non-limiting examples of commercially available antioxidants include Irganox 1010 available from BASF, or Doverphos S9228T available from Dover Chemical Company.

[0070] In forming the HDPE composition, the various components of the HDPE, the optics enhancing insoluble/immiscible polymeric additive and clarifying and/or nucleating agent, as described, along with any additional optional additives, can be dry blended. The HDPE component may be in the form of pellets, powder, flakes or fluff. The materials are combined in a customary mixing machine, in which the HDPE, optics-enhancing insoluble/immiscible polymeric additive additives, and nucleating agents are mixed with any optional additional or secondary additives. The optional additional additives can be added at the end or during the processing steps to produce the polymer blend. Suitable machines for such mixing are known to those skilled in the art. Non-limiting examples include mixers, kneaders and extruders. These materials are then fed directly into the feed zone of an extruder. In certain cases, the process can be carried out in an extruder and introduction of the additives may occur during processing. Non-limiting examples of suitable extruders include single-screw extruders, counter-rotating and co-rotating twin-screw extruders, planetary-gear extruders, ring extruders, or co-kneaders. The process can be performed at a temperature from 160 °C to 300 °C.

[0071] In some embodiments, the HDPE, optics-enhancing additives of the insoluble or immiscible polymeric additive and clarifying and/or nucleating agents, and any optional secondary additives, used to produce the polymer blend of the present invention can be melt- extruded by following typical procedures of weighing the required amounts of the HDPE and additives, followed by dry blending, and then feeding the mixture into a main feeder of a twin- screw co-rotating extruder (length/diameter (L/D) ratio of 25:1 or 40:1) to obtain the final composition. The HDPE, additives, or blend thereof can be subjected to an elevated temperature for a sufficient period of time during blending. The blending temperature can be above the softening point of the polymers. In certain aspects, the extrusion process can be performed at a temperature from 160 °C to 300 °C. The optics-enhancing insoluble or immiscible polymeric additives and clarifying and/or nucleating agents can be added along with other optional additives in-line and prior to pelletization of the HDPE resin during the production process. The amounts of additives combined with the HDPE can be adjusted to provide those weight amounts previously discussed.

[0072] The optional secondary additives can be premixed or added individually to the polymer blend or the different components thereof. By way of example, the secondary additives of the present invention can be premixed such that the blend is formed prior to adding it to the HDPE or the optics-enhancing additives. The blend thereof can be subjected to an elevated temperature for a sufficient period of time during blending and/or incorporation of additives. Incorporation of optional secondary additives into the polymer resin can be carried out, for example, by mixing the above-described components using methods customary in process technology. The blending temperature can be above the softening point of the polymers. In certain aspects, a process can be performed at a temperature from 160 °C to 300 °C. Such “melt mixing” or “melt compounding” results in uniform dispersion of the present optional additives in the HDPE and/or optics-enhancing additives.

[0073] Articles (e.g., caps, bottles and containers) that are manufactured from the blend of HDPE and optics-enhancing additives can have a higher transparency and/or reduced haze than articles of manufacture made from HDPE without such additives. In particular, the HDPE composition may have a transparency of from 80% or more and a haze of from 60% or less as determined by ASTM D1003 at a thickness of from 1 mm or more, without any drawing, stretching or orienting of the HDPE composition. In certain instances the HDPE composition may have a transparency of at least, equal to, and/or between any two of 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, and 100%, as determined by ASTM D1003 at a thickness of from 1 mm or more, with or without any drawing, stretching or orienting of the HDPE composition. The haze of the HDPE composition may be from at least equal to, and/or between any two of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, and 60%, as determined by ASTM D1003 at a thickness of from 1 mm or more, with or without any drawing, stretching or orienting of the HDPE composition. In some embodiments, the transparency of the HDPE composition may provide an article with a transparency of from 90% or more and a haze of from 60% or less as determined by ASTM D1003 at a thickness of from 1 mm or more, with or without any drawing, stretching or orienting the HDPE composition.

[0074] The polymer blend compositions formed as described are normally collected as pellets, which can be stored for a time or employed immediately in a forming process. The forming processes can include injection molding, blow molding, compression molding, sheet extrusion, film blowing, pipe extrusion, profile extrusion, calendaring, thermoforming, rotomolding, or combinations thereof. The final formed articles can be, for instance, molded parts, sheets, films, or fibers. Examples of molded parts include a cap, a bottle cap, a container, a bottle, a lid, a sheet, a pipe, a pipe coupling, a bottle, a cup, a tray, a pallet, or a toy, or combinations thereof. Caps can be injection and/or compression molded. The caps may be threaded or non- threaded caps for selectively closing off openings to bottles or other containers. Such caps can be used in a variety of food and non-food applications. By way of example, caps and containers that include the polymer blend of the present invention can be used with containers for storing carbonated beverages, pressurized beverages, or the like.

[0075] The following examples serve to further illustrate various embodiments and applications.

EXAMPLES

EXAMPLE 1

[0076] Different optics-enhancing additives comprising insoluble or immiscible polymeric additives in combination with clarifying and/or nucleating agents were used for increasing the transparency and/or reducing haze in HDPE compositions. The HDPE compositions were prepared using SABIC^® HDPE B5823, which is a unimodal HDPE having an MFR at 190° C and 5 kg of 0.9 g/10 min and density of 958 kg/m³. Different optics-enhancing additives for increasing the transparency and/or reducing haze in HDPE were used with the B5823 HDPE. Both transparency and haze of the HDPE samples were measured using a Haze-Guard Plus transparency meter, available from BYK Gardner, according to ASTM D1003. For comparison purpose, neat B5823 HDPE without any optics-enhancing additives, was also extruded and tested for its optical properties. The different mixtures were fed into a hopper of a ZSK-25 mm 10-barrel twin-screw extruder with an L/D ratio of 25:1. The operating parameters used are set forth in Table 1 below:

Table 1

[0077] The torque measured during the melt extrusion of the neat and formulated HDPE with optics enhancing insoluble/immiscible polymeric additives was in the range of 34%-36%, indicating that the processability of HDPE was not hampered significantly with the incorporation of optics-enhancing additives.

[0078] The pellets obtained after the melt extrusion of Example 1 were compression molded into 1.2 mm thick sheets at a temperature of 195 °C to 210 °C, with a holding time of 5 min and a cooling time of 5 min. No visual inhomogeneity was evident in the compression molded sheets. The compression molded sheets, both the neat and formulated HDPE, were then evaluated for optical performance according to ASTM D1003 method.

[0079] The % transmittance (%T) value of 1.2 mm thick compression molded sheet, along with that of blends of HDPE B5823 and different optics enhancing insoluble/immiscible polymeric additives such as ethylene vinyl alcohol (EVOH), polyethylene glycol (PEG) and cyclic olefin copolymers (COC) in combination of different nucleating agents such as HPN 20E (calcium salt of cyclohexane dicarboxylic acid) and sorbitol are presented in the Table 2 below.

Table 2

[0080] While the invention has been shown in some of its for s, it should be apparent to those skilled in the art that it is not so limited, but is susceptible to various changes and modifications without departing from the scope of the invention based on experimental data or other optimizations considering the overall economics of the process. Accordingly, it is appropriate that the appended claims be construed broadly and, in a manner, consistent with the scope of the invention.

Claims

CLAIMS We claim:

1. A high-density polyethylene (HDPE) composition having increased transparency and/or reduced haze, the composition comprising a mixture of a HDPE, a polymeric additive that is insoluble or immiscible with the HDPE, and a clarifying and/or nucleating agent in an amount of 50 ppm to 500 ppm by total weight of the HDPE composition, the HDPE composition having at least one of a transparency of from 80% or more and a haze of from 60% or less as determined by ASTM D1003 at a thickness of from 1 mm or more.

2. The composition of claim 1, wherein: the HDPE composition has at least one of a transparency of from 90% or more and a haze of from 50% or less as determined by ASTM D1003 at a thickness of from 1 mm or more, without drawing, stretching or orienting the HDPE composition.

3. The composition of any of cl aims 1-2, wherein: the HDPE is at least one of a unimodal, bimodal, and multimodal HDPE.

4. The composition of any of cl aims 1-3, wherein: the HDPE has at least one of: an average molecular weight (Mw) of from 130,000 to 300,000 as determined by high temperature gel permeation chromatography; a poly dispersity index (PDI = Mw/Mn) of from 2 to 25 as determined by high temperature gel permeation chromatography; a melt flow rate (MFR) at 190 °C and 5 kg of from 0.1 g/10 min to 20 g/10 min as per ISO 1133; and a density of from 940 kg/m3 to 965 kg/m3 as per ASTM D1505.

5. The composition of any of claims 1-4, wherein: the polymeric additive is present in an amount of from 0.1 wt.% to 5 wt.% by total weight of the HDPE composition.

6. The composition of any of cl aims 1-5, wherein: the polymeric additive is comprised of a polymer containing functional groups of at least one of an OH group, an ionic group, a norbornyl group, an ether (ROR') group, a cyclic olefin group, and a cyclic amide group.

7. The composition of any of cl aims 1-6, wherein: the polymeric additive is selected from at least one of a low molecular weight polyethylene glycol (PEG), a high molecular weight polyethylene glycol (PEG), a silyated PEG, an ethylene vinyl alcohol (EVOH) having an ethylene content of from 25 mol% to 50 mol%, an ethylene vinyl acetate (EVA), a polyvinylpyrrolidone (PVP), an ionomeric polyethylene, a cyclic olefin copolymer, a sytrenic copolymer, and combinations thereof.

8. The composition of any of cl aims 1-7, wherein: the clarifying and/or nucleating agent is present in an amount of 100 ppm to 200 ppm by total weight of the HDPE composition.

9. The composition of any of cl ai 1-8, wherein: the clarifying and/or nucleating agent is selected from at least one of a sorbitol derivative, 1,2,3,4-bis-dibenzylidene sorbitol (DBS), l,2,3,4-bis-(p-methoxybenzylidene sorbitol) (DOS), l,2,3,4-bis-(3,4-dimethylbenzylidene sorbitol) (MBDS), and l,3:2,4-di(3,4- dimethylbenzylidene) sorbitol (DMDBS), a calcium salt of dicarboxylic acid, a metal salt of cyclohexane dicarboxylic acid, a bisamide, a lithium carbonate, a benzoic acid, an inorganic oxide, nano-zinc oxide, talc, clay, a powdered polymeric agent, polyphenylene oxide, polyvinylenedifluoride, polycarbonate, polycarbonate- siloxane copolymer, cross-linked polycarbonate, polyetherimide, polyamide, ethylene propylene diene monomer, and polyoxymethylene.

10. The composition of any of cl aims 1-9, wherein: the HDPE is a copolymer with comonomers selected from C3 to C10 olefin monomers, the comonomers being present in the HDPE copolymer in an amount of from 2 wt.% or less.

11. The composition of any of cl aims 1-10, further comprising: at least one of a heat conductive agent, a tie agent, an antiblocking agent, an antistatic agent, an antioxidant, a neutralizing agent, an acid scavenger, a blowing agent, a crystallization aid, a dye, a flame retardant agent, a filler, a hard filler, a soft filler, an impact modifier, a mold release agent, an oil, another polymer, a pigment, a processing agent, a reinforcing agent, a stabilizer, a light stabilizer, an UV resistance agent, a slip agent, a flow modifying agent, and combinations thereof.

12. The composition of any of cl aims 1-11, wherein: the HDPE composition is formed into an article of manufacture.

13. The composition of claim 12, wherein: the article is at least one of a film, a molded part, a container, a beverage container cap, a lid, a sheet, a pipe, a pipe coupling, a bottle, a cup, a tray, a pallet, and a toy.

14. A high-density polyethylene (HDPE) composition having increased transparency and/or reduced haze, the composition comprising a mixture of a HDPE, a polymeric additive that is insoluble or immiscible with the HDPE in an amount of from of from 0.1 wt.% to 2 wt.% by total weight of the HDPE composition, and a clarifying and/or nucleating agent in an amount of 100 ppm to 500 ppm by total weight of the HDPE composition, the HDPE composition having at least one of a transparency of from 80% or more and a haze of from 40% or less as determined by ASTM D1003 at a thickness of from 1 mm or more, without drawing, stretching or orienting the HDPE composition; and wherein: the polymeric additive is selected from at least one of, a low molecular weight polyethylene glycol (PEG), a high molecular weight polyethylene glycol (PEG), a silyated PEG, an ethylene vinyl alcohol (EVOH) having an ethylene content of from 25 mol% to 50 mol%, an ethylene vinyl acetate (EVA), a polyvinylpyrrolidone (PVP), an ionomeric polyethylene, a cyclic olefin copolymer, a styrenic copolymer, and combinations thereof; the clarifying and/or nucleating agent is selected from at least one of a sorbitol derivative, 1,2,3,4-bis-dibenzylidene sorbitol (DBS), l,2,3,4-bis-(p-methoxybenzylidene sorbitol) (DOS), l,2,3,4-bis-(3,4-dimethylbenzylidene sorbitol) (MBDS), and l,3:2,4-di(3,4- dimethylbenzylidene) sorbitol (DMDBS), a calcium salt of dicarboxylic acid, a metal salt of cyclohexane dicarboxylic acid, a bisamide, a lithium carbonate, a benzoic acid, an inorganic oxide, nano-zinc oxide, talc, clay, a powdered polymeric agent, polyphenylene oxide, polyvinylenedifluoride, polycarbonate, polycarbonate- siloxane copolymer, cross-linked polycarbonate, polyetherimide, polyamide, ethylene propylene diene monomer, and polyoxymethylene.

15. The composition of claim 14, wherein: the clarifying and/or nucleating agent is present in an amount of 100 ppm to 200 ppm by total weight of the HDPE composition.

16. The composition of any of claims 14-15, wherein: the HDPE is at least one of a unimodal, bimodal, and multimodal HDPE.

17. The composition of any of cl aims 14-16, wherein: the HDPE has at least one of: an average molecular weight (Mw) of from 130,000 to 300,000 as determined by high temperature gel permeation chromatography; a poly dispersity index (PDI = Mw/Mn) of from 13 to 25 as determined by high temperature gel permeation chromatography; a melt flow rate (MFR) at 190 °C and 5 kg of from 0.1 g/10 min to 20 g/10 min as per ISO 1133; and a density of from 940 kg/m3 to 965 kg/m3 as per ASTM D1505.

18. The composition of any of cl aims 14-17, wherein: the HDPE composition is formed into an article of manufacture.

19. The composition of claim 18, wherein: the article is at least one of a film, a molded part, a container, a bottle, a beverage container cap, a lid, a sheet, a pipe, a pipe coupling, a bottle, a cup, a tray, a pallet, and a toy.

20. A method of forming a high-density polyethylene (HDPE) composition having increased transparency and/or reduced haze, the method comprising: modifying a HDPE by combining the HDPE with a polymeric additive that is insoluble or immiscible with the HDPE, and a clarifying and/or nucleating agent in an amount of 100 ppm to 500 ppm by total weight of the HDPE composition so that the HDPE composition has at least one of a transparency of from 80% or more and a haze of from 60% or less as determined by ASTM D1003 at a thickness of from 1 mm or more.