# US 11,306,196 B2 · Polyethylene composition and film having retained dart impact > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,306,196 B2 - Document ID: US11306196B2 - Status: Granted - Kind: B2 - Application number: 16/507,616 - Filed: 2019-07-10 - Published: 2020-01-16 - Granted: 2022-04-19 - Earliest claimed: 2018-07-11 - Assignees: NOVA Chemicals (International) S.A. - Applicants: NOVA Chemicals (International) S.A. - Inventors: XiaoChuan Wang; Peter Zoricak; Brian Molloy; Qinyan Wang; Lawrence VanAsseldonk; Norman Aubee - Web page: https://patentgrep.com/patent/US11306196B2 ## CPC - C08F 210/16: Copolymers of ethene with alpha-alkenes, e.g. EP rubbers - C08L 23/06: Polyethylene - C08J 5/18: Manufacture of films or sheets - C08L 23/08: Copolymers of ethene (C08L23/16 takes precedence) - C08F 4/65908: {in combination with an ionising compound other than alumoxane, e.g. (C6F5)4B-X+} - C08F 4/65912: {in combination with an organoaluminium compound} - C08F 2420/04: Cp or analog not bridged to a non-Cp X ancillary anionic donor - C08J 2323/06: Polyethene - C08J 2323/08: Copolymers of ethene (C08J2323/16 takes precedence) - C08J 2423/06: Polyethene - C08J 2423/08: Copolymers of ethene (C08J2423/16 takes precedence) - C08L 2203/16: used for films - C08L 2203/162: sealable films - C08L 2205/025: containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure - C08L 2205/03: containing three or more polymers in a blend - C08L 2207/066: LDPE (radical process) - C08L 2308/00: Chemical blending or stepwise polymerisation process with the same catalyst - C08L 2314/02: Ziegler natta catalyst - C08L 2314/06: Metallocene or single site catalysts - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) ## Abstract A polyethylene composition including a first polyethylene which is an ethylene copolymer having a weight average molecular weight of from 70,000 to 250,000 and a molecular weight distribution Mw/Mn of <2.3, a second polyethylene which is an ethylene copolymer or homopolymer having a weight average molecular weight of less than 75,000 and a molecular weight distribution Mw/Mn of <2.3, and a third polyethylene which is an ethylene copolymer or homopolymer having a weight average molecular weight of from 100,000 to 300,000 and a molecular weight distribution Mw/Mn of >2.3, where the first polyethylene has more short chain branching than the second polyethylene or the third polyethylene. The polyethylene composition has a soluble fraction in a CEF analysis of at least 15 weight percent. A film made from the polyethylene composition may have a machine direction 1% secant modulus of ≥200 MPa (at a film thickness of about 1 mil) and an oxygen transmission rate (OTR) of ≥700 cm3 per 100 inch2 per day (at a film thickness of about 1 mil). A film made from the polyethylene composition retains much of its dart impact performance on downgauging from a thickness of 1 mil to a thickness of 0.75 mil. ## Claims ### Claim 1 A polyethylene composition comprising: from 15 to 75 wt % of a first polyethylene which is an ethylene copolymer, the first polyethylene having a weight average molecular weight Mw of from 70,000 to 250,000, a molecular weight distribution Mw/Mn of <2.3 and from 5 to 100 short chain branches per thousand carbon atoms; from 5 to 80 wt % of a second polyethylene which is an ethylene copolymer or an ethylene homopolymer, the second polyethylene having a weight average molecular weight Mw of less than 75,000, a molecular weight distribution Mw/Mn of <2.3 and from 0 to 20 short chain branches per thousand carbon atoms; and from 5 to 60 wt % of a third polyethylene which is an ethylene copolymer or an ethylene homopolymer, the third polyethylene having a weight average molecular weight Mw of from 100,000 to 300,000, a molecular weight distribution Mw/Mn of >2.3 and from 0 to 75 short chain branches per thousand carbon atoms; wherein the number of short chain branches per thousand carbon atoms in the first polyethylene (SCBPE-1) is greater than the number of short chain branches per thousand carbon atoms in the second polyethylene (SCBPE-2) and the third polyethylene (SCBPE-3); the number of short chain branches per thousand carbon atoms in the third polyethylene (SCBPE-3) is greater than the number of short chain branches per thousand carbon atoms in the second polyethylene (SCBPE-2); and the weight average molecular weight of the second polyethylene is less than the weight average molecular weight of the first polyethylene and the third polyethylene; wherein, the polyethylene composition has a density of ≤0.939 g/cm3, a melt index I2, determined at 190° C., of from 0.1 to 10 dg/min, a melt flow ratio, I21/I2 of greater than 40 and has a soluble fraction in a crystallization elution fractionation (CEF) analysis of at least 15 weight percent. ### Claim 2 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has a bimodal profile in a gel permeation chromatograph (GPC). ### Claim 3 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has a soluble fraction in a crystallization elution fractionation (CEF) analysis of at least 20 weight percent. ### Claim 4 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has a melting peak temperature in a differential scanning calorimetry (DSC) analysis at above 125° C. ### Claim 5 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has two melting peaks in a differential scanning calorimetry (DSC) analysis. ### Claim 6 (depends on 1) The polyethylene composition of claim 1 wherein the first polyethylene has from 25 to 75 short chain branches per thousand carbon atoms. ### Claim 7 (depends on 1) The polyethylene composition of claim 1 wherein the second polyethylene is an ethylene homopolymer. ### Claim 8 (depends on 1) The polyethylene composition of claim 1 wherein the third polyethylene is an ethylene copolymer and has from 5 to 50 short chain branches per thousand carbon atoms. ### Claim 9 (depends on 1) The polyethylene composition of claim 1 wherein the first polyethylene has a weight average molecular weight, Mw of from 75,000 to 200,000. ### Claim 10 (depends on 1) The polyethylene composition of claim 1 wherein the second polyethylene has a weight average molecular weight, Mw of from 15,000 to 40,000. ### Claim 11 (depends on 1) The polyethylene composition of claim 1 wherein the third polyethylene has a weight average molecular weight, Mw of from 100,000 to 240,000. ### Claim 12 (depends on 1) The polyethylene composition of claim 1 wherein the first polyethylene has a density of from 0.865 to 0.916 g/cm3. ### Claim 13 (depends on 1) The polyethylene composition of claim 1 wherein the second polyethylene is an ethylene homopolymer having a density of from 0.940 to 0.980 g/cm3. ### Claim 14 (depends on 1) The polyethylene composition of claim 1 wherein the third polyethylene is an ethylene copolymer having a density of from 0.880 to 0.936 g/cm3. ### Claim 15 (depends on 1) The polyethylene composition of claim 1 wherein the first polyethylene is present in from 20 to 70 wt %. ### Claim 16 (depends on 1) The polyethylene composition of claim 1 wherein the second polyethylene is present in from 15 to 60 wt %. ### Claim 17 (depends on 1) The polyethylene composition of claim 1 wherein the third polyethylene is present in from 5 to 50 wt %. ### Claim 18 (depends on 1) The polyethylene composition of claim 1 wherein the first polyethylene has a CDBI50 of at least 75 wt %. ### Claim 19 (depends on 1) The polyethylene composition of claim 1 wherein the third polyethylene is a copolymer with a CDBI50 of less than 75 wt %. ### Claim 20 (depends on 1) The polyethylene composition of claim 1 wherein the first polyethylene is a homogeneously branched ethylene copolymer. ### Claim 21 (depends on 1) The polyethylene composition of claim 1 wherein the third polyethylene is a heterogeneously branched ethylene copolymer. ### Claim 22 (depends on 1) The polyethylene composition of claim 1 wherein the first polyethylene is a made with a single site catalyst. ### Claim 23 (depends on 1) The polyethylene composition of claim 1 wherein the third polyethylene is made with a Ziegler-Natta catalyst. ### Claim 24 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has a molecular weight distribution Mw/Mn of from 2.3 to 8.0. ### Claim 25 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has a molecular weight distribution Mw/Mn of from 2.5 to 6.5. ### Claim 26 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has a density of <0.935 g/cm3. ### Claim 27 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has a density of from 0.880 to 0.932 g/cm3. ### Claim 28 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has a melt index, I2 of from 0.1 to 3.0 dg/min. ### Claim 29 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has a Mz/Mw of less than 4.0. ### Claim 30 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has a melt index ratio, I21/I2 of from greater than 40 to 100. ### Claim 31 (depends on 1) The polyethylene composition of claim 1 wherein the polyethylene composition has a melt index ratio, I21/I2 of greater than 45. ### Claim 32 (depends on 1) A film layer having a thickness of from 0.5 to 10 mil, comprising the polyethylene composition of claim 1. ### Claim 33 (depends on 1) The polyethylene composition of claim 1, which when made into a film layer having a thickness of about 1 mil exhibits a machine direction (MD) 1% secant modulus of ≥200 MPa. ### Claim 34 (depends on 1) The polyethylene composition of claim 1, which when made into a film layer having a thickness of about 1 mil exhibits an oxygen transmission rate (OTR) of ≥700 cm3 per 100 inches2 per day. ### Claim 35 (depends on 1) The polyethylene composition of claim 1, which when made into a film layer having a thickness of about 1 mil exhibits a machine direction (MD) 1% secant modulus of ≥200 MPa and an oxygen transmission rate (OTR) of ≥700 cm3 per 100 inches2 per day. ### Claim 36 (depends on 1) The polyethylene composition of claim 1, which when made into a film layer having a thickness of about 1 mil exhibits a first dart impact value in g/mil and when made into a film layer having a thickness of about 0.75 mil exhibits a second dart impact value in g/mil; wherein the second dart impact value is within 15 percent of the first dart impact value. ### Claim 37 (depends on 1) A film comprising the polyethylene composition of claim 1, the film satisfying the following relationship: oxygen transmission rate (OTR in cm3 per 100 inches2 per day)>−5.4297(machine direction (MD) 1% secant modulus in MPa)+1767.8; wherein the OTR is measured at a film thickness of about 1 mil, and the machine direction (MD) 1% secant modulus is measured at a film thickness of about 1 mil. ### Claim 38 (depends on 1) The polyethylene composition of claim 1 wherein the second polyethylene is a made with a single site catalyst.