# US 10,246,566 B2 · Polyethylene polymer powder and method of producing same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,246,566 B2 - Document ID: US10246566B2 - Status: Granted - Kind: B2 - Application number: 15/924,682 - Filed: 2018-03-19 - Published: 2018-09-27 - Granted: 2019-04-02 - Earliest claimed: 2017-03-21 - Assignees: Asahi Kasei Kabushiki Kaisha - Applicants: Asahi Kasei Kabushiki Kaisha - Inventors: Akitomo Kikuchi - Web page: https://patentgrep.com/patent/US10246566B2 ## CPC - C08J 3/28: Treatment by wave energy or particle radiation - A61F 2/34: Acetabular cups - A61L 27/16: obtained by reactions only involving carbon-to-carbon unsaturated bonds - C08F 10/02: Ethene - A61F 2002/30065: {thermoplastic, i.e. softening or fusing when heated, and hardening and becoming rigid again when cooled} - A61L 2430/24: for joint reconstruction - C08F 2/14: Organic medium - C08F 4/65916: {supported on a carrier, e.g. silica, MgCl2, polymer} - C08F 4/65927: {two cyclopentadienyl rings being mutually bridged} - C08F 2810/20: leading to a crosslinking, either explicitly or inherently - C08J 2323/06: Polyethene - 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) - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) - A61L: METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES (preservation of bodies or disinfecting characterised by the agents employed A01N; preserving, e.g. sterilising, food or foodstuffs A23; preparations for medical, dental or toiletry purposes A61K) - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS ## Abstract Provided are a polyethylene polymer powder and method of producing the same that can improve molding efficiency while maintaining high levels of molded product strength and wear resistance. The polyethylene polymer powder comprises an ethylene homopolymer or copolymer and has an intrinsic viscosity IV of at least 12 dL/g and not more than 35 dL/g, a melting peak full width at half maximum of at least 2° C. and not more than 7° C., a span (laser particle size distribution measurement) of at least 0.9 and not more than 2, and an α-olefin content of 0 mol % to not more than 1.50 mol %. The method of producing this polyethylene polymer powder includes polymerizing ethylene or ethylene and an α-olefin by slurry polymerization using a loop reactor. In the polymerizing, supply of a solvent and ethylene or supply of a solvent, ethylene, and an α-olefin is performed by a plurality of supply lines. ## Claims ### Claim 1 A polyethylene polymer powder comprising an ethylene homopolymer or a copolymer of ethylene and an α-olefin having a carbon number of at least 3 and not more than 8, wherein the polyethylene polymer powder has an intrinsic viscosity IV of at least 12 dL/g and not more than 35 dL/g as measured at 135° C. in decalin solvent, the polyethylene polymer powder has a melting peak full width at half maximum of at least 2° C. and not more than 7° C. as measured by differential scanning calorimetry at a heating rate of 10° C./min, the polyethylene polymer powder has a span of at least 0.9 and not more than 2 as determined by laser particle size distribution measurement in methanol, and the polyethylene polymer powder has an α-olefin content of 0 mol % to not more than 1.50 mol % as measured by 13C-NMR. ### Claim 2 (depends on 1) The polyethylene polymer powder according to claim 1, wherein the polyethylene polymer powder has a heat of fusion ΔH1 of at least 100 J/g and not more than 200 J/g as measured by differential scanning calorimetry at a heating rate of 10° C./min, and a temperature at which 5% heat of fusion of the heat of fusion ΔH1 is reached is at least 90° C. and not higher than 120° C. ### Claim 3 (depends on 1) The polyethylene polymer powder according to claim 1 for a compression molded product. ### Claim 4 (depends on 1) The polyethylene polymer powder according to claim 1 for a prosthetic joint. ### Claim 5 (depends on 1) A prosthetic joint comprising a crosslinked molded product obtained through γ-ray irradiation of a molded product of the polyethylene polymer powder according to claim 1. ### Claim 6 (depends on 1) A method of producing the polyethylene polymer powder according to claim 1, comprising: polymerizing ethylene or ethylene and an α-olefin by slurry polymerization using a loop reactor, wherein in the polymerizing, supply of a solvent and ethylene or supply of a solvent, ethylene, and an α-olefin is performed by a plurality of supply lines. ### Claim 7 (depends on 2) The polyethylene polymer powder according to claim 2 for a compression molded product. ### Claim 8 (depends on 2) The polyethylene polymer powder according to claim 2 for a prosthetic joint. ### Claim 9 (depends on 2) A prosthetic joint comprising a crosslinked molded product obtained through γ-ray irradiation of a molded product of the polyethylene polymer powder according to claim 2. ### Claim 10 (depends on 2) A method of producing the polyethylene polymer powder according to claim 2, comprising: polymerizing ethylene or ethylene and an α-olefin by slurry polymerization using a loop reactor, wherein in the polymerizing, supply of a solvent and ethylene or supply of a solvent, ethylene, and an α-olefin is performed by a plurality of supply lines.