# US 7,411,026 B2 · Polymers of ethylene and, optionally, copolymerizable esters, films using such polymers and stretch hood packaging processes using such films > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,411,026 B2 - Document ID: US7411026B2 - Status: Granted - Kind: B2 - Application number: 10/796,831 - Filed: 2004-07-28 - Published: 2005-02-17 - Granted: 2008-08-12 - Earliest claimed: 2004-07-28 - Assignees: ExxonMobil Chemical Patents Inc. - Inventors: Stefan Bertil Ohlsson; Bart Lauwers; Jan C. Donck; Jef Vaes - Web page: https://patentgrep.com/patent/US7411026B2 ## CPC - B32B 27/08: of synthetic resin - B01J 19/2415: {Tubular reactors} - B32B 27/18: characterised by the use of special additives - B32B 27/32: comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} - B32B 27/322: {comprising halogenated polyolefins, e.g. PTFE} - C08F 210/02: Ethene - C08F 210/16: Copolymers of ethene with alpha-alkenes, e.g. EP rubbers - C08J 5/18: Manufacture of films or sheets - B01J 2219/00006: Large-scale industrial plants - B01J 2219/00094: Jackets - B01J 2219/00108: involving reactant vapours - B32B 2323/046: LDPE, i.e. low density polyethylene - B32B 2439/00: Containers; Receptacles - C08J 2323/04: Homopolymers or copolymers of ethene - C08J 2323/08: Copolymers of ethene (C08J2323/16 takes precedence) - Y10T 428/1328: Shrinkable or shrunk [e.g., due to heat, solvent, volatile agent, restraint removal, etc.] - Y10T 428/269: including synthetic resin or polymer layer or component - Y10T 428/31855: Of addition polymer from unsaturated monomers - Y10T 428/31913: Monoolefin polymer - Y10T 428/31935: Ester, halide or nitrile of addition polymer - Y10T 428/31938: Polymer of monoethylenically unsaturated hydrocarbon - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - 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) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Polymers comprising units derived from ethylene, said polymer having: a) a Melt Index of from 0.05 to 20 g/10 min. as determined by ASTM-1238 Condition E; b) at least 10 per 1000 C-atoms of short chain branches, containing five carbon atoms or less, as determined by C13 NMR, and less than 3.5 mol %, of units derived from a copolymerizable ethylenically unsaturated ester; c) a density of from 0.90 to 0.94 g/cm3, preferably 0.91 to 0.935 g/cm3, especially 0.92 to 0.93 g/cm3 as determined by ASTM D1505; and d) a relaxation time as described herein of at least 10 s. Such polymers can be obtained by free radical polymerization using a chain transfer agent that incorporates into the polymer chain such as an alpha-olefin, preferably propylene, as a chain transfer agent, preferably in a tubular reactor under circumstances to favor LCB formation in a down stream part of the tubular reactor. ## Claims ### Claim 1 Polymer comprising units derived from ethylene, said polymer having: a) a Melt Index of from 0.05 to 20 g/10 min, as determined by ASTM-1238 Condition E; b) at least 10 per 1000 C-atoms of C1- to C5 short chain branches as determined by C13 NMR, and 1 to 3.5 mol % of units derived from a copolymerizable ethylenically unsaturated ester; c) a density of from 0.90 to 0.94 g/cm3, as determined by ASTM D1505, and d) a rheological relaxation time of at least 10 s, wherein the polymer is obtained by free radical polymerization using an α-olefin chain transfer agent. ### Claim 2 (depends on 1) Polymer as claimed in claim 1 which contains at least four short chain branches per thousand carbon atoms containing three carbon atoms or less. ### Claim 3 (depends on 1) Polymer as claimed in claim 1 which contains at least five short chain branches per thousand carbon atoms containing three carbon atoms or less. ### Claim 4 (depends on 1) Polymer as claimed in claim 1 which contains less than 30 per 1000 C-atoms of short chain branches, containing five carbon atoms or less, as determined by C13 NMR. ### Claim 5 (depends on 1) Polymer as claimed in claim 1 which contains less than 20 per 1000 C-atoms of short chain branches, containing five carbon atoms or less, as determined by C13 NMR. ### Claim 6 (depends on 1) Polymer as claimed in claim 1 wherein the copolymerizable ethylenically unsaturated ester comprises ethylene vinyl acetate. ### Claim 7 (depends on 1) Polymer as claimed in claim 1 wherein the polymer contains at least 1 per 1000 C-atoms of all long chain branches, containing 6 or more carbon atoms as determined by C13 NMR. ### Claim 8 (depends on 1) Polymer as claimed in claim 1 wherein the polymer contains at least 5, per 1000 C-atoms of all long chain branches, containing 6 or more carbon atoms as determined by C13 NMR. ### Claim 9 (depends on 1) Polymer as claimed in claim 1 wherein the polymer contains from 1 to 3 mol % of units derived from a copolymerizable ethylenically unsaturated ester and at least 1 per 1000 C-atoms of all long chain branches, containing 6 or more carbon atoms as determined by C13 NMR. ### Claim 10 (depends on 1) Polymer as claimed in claim 1 wherein the polymer has a bimodal molecular weight distribution as determined by GPC DRI. ### Claim 11 (depends on 1) Polymer as claimed in claim 1 wherein the polymer has a relaxation time is less than 20 s. ### Claim 12 (depends on 1) Polymer as claimed in claim 1 wherein the polymer has a Melt Index of less than 15 g/10 min. ### Claim 13 (depends on 1) Polymer as claimed in claim 1 wherein the polymer has a Melt Index of less than 10 g/10 min. ### Claim 14 (depends on 1) Polymer as claimed in claim 1 wherein the polymer has a Melt Index of from 0.1 to 4 g/10 min for blown film extrusion. ### Claim 15 (depends on 14) Polymer as claimed in claim 14 wherein the polymer has a Melt Index of less than 2 g/10 min. ### Claim 16 (depends on 14) Polymer as claimed in claim 14 wherein the polymer has a Melt Index of less than 1 g/10 min. ### Claim 17 (depends on 1) Polymer as claimed in claim 1 wherein the density is 0.91 to 0.935 g/cm3. ### Claim 18 (depends on 1) Polymer as claimed in claim 1 wherein the density is 0.92 to 0.93 g/cm3. ### Claim 19 Polymer, comprising units derived from ethylene, obtained by free radical polymerization using a chain transfer agent that incorporates into the polymer chain to provide a polymer having a Melt Index of from 0.05 to 20 g/10 min as determined by ASTM-D 1238 Condition E; less than 3.5 mol % of units derived from a copolymerizable ethylenically unsaturated ester; and at least 10 per 1000 C-atoms of short chain branches, containing five carbon atoms or less, as determined by C13 NMR, wherein the chain transfer agent is an α-olefin, and in which the polymer is produced in a tubular reactor under circumstances to favor LCB formation in a downstream part of the tubular reactor and has a density of from 0.90 to 0.94 g/cm3. ### Claim 20 (depends on 19) Polymer as claimed in claim 19 wherein the chain transfer agent that incorporates into the polymer chain is propylene. ### Claim 21 (depends on 19) Polymer as claimed in claim 19, wherein the copolymerizable ethylenically unsaturated ester comprises ethylene vinyl acetate. ### Claim 22 (depends on 19) Polymer according to claim 19 in which the polymer has a density of 0.91 to 0.935 g/cm3 as determined by ASTM D1505, and a relaxation time as described herein of at least 10 s. ### Claim 23 (depends on 19) Polymer according to claim 19 in which the polymer has a density of 0.92 to 0.93 g/cm3 as determined by ASTM D1505. ### Claim 24 (depends on 19) Polymer as claimed in claim 19, comprising from 1 to 3.5 mol % of units derived from a copolymerizable ethylenically unsaturated ester.