US 12,421,333 B2
Polyethylene powder and molded article thereof
Kazuya Shikata, Tokyo (JP); and Haruka Yokoyama, Tokyo (JP)
Assigned to Asahi Kasei Kabushiki Kaisha, Tokyo (JP)
Appl. No. 17/792,007
Filed by Asahi Kasei Kabushiki Kaisha, Tokyo (JP)
PCT Filed Jan. 25, 2021, PCT No. PCT/JP2021/002500
§ 371(c)(1), (2) Date Jul. 11, 2022,
PCT Pub. No. WO2021/153520, PCT Pub. Date Aug. 5, 2021.
Claims priority of application No. 2020-015473 (JP), filed on Jan. 31, 2020.
Prior Publication US 2023/0056794 A1, Feb. 23, 2023
Int. Cl. H01M 50/417 (2021.01); C08F 110/02 (2006.01); C08J 3/12 (2006.01)
CPC C08F 110/02 (2013.01) [C08J 3/12 (2013.01); H01M 50/417 (2021.01)] 20 Claims
OG exemplary drawing
 
1. A polyethylene powder satisfying the following Requirements 1 to 3:
Requirement 1: viscosity-average molecular weight (Mv) is 200,000 or more and 3,000,000 or less
Requirement 2: complex viscosity |η*|m, obtained by measurement under the following <Conditions for Measurement of Slurry Viscoelasticity,> satisfies the following formula (1):
590.0×(Mv×10−4)1.18≥|η*|m≥13.3×(Mv×10−4)1.18  (1)
<Conditions for Measurement of Slurry Viscoelasticity>
measuring apparatus: MARS III manufactured by Thermo Fisher Scientific K.K.
stage: 20 mm ϕ
plate: 20 mm ϕ parallel plate
gap: 0.5 mm
slurry composition: 30 parts by mass of a polyethylene powder, 70 parts by mass of a liquid paraffin
the polyethylene powder: a powder passing through a sieve having an opening of 425 μm in accordance with a JIS Z 8801 standard is used for measurement
measurement conditions: complex viscosity |η*| is measured by the following steps 1 to 2:
step 1: a slurry is kept at 100° C. for 2 min
step 2: after the step 1, temperature is increased from 100° C. to 140° C. at 1° C./min, and viscoelasticity during the temperature increase is measured at a frequency of 1 Hz and a strain of 10% under a nitrogen atmosphere
determination of |η*|m: a temperature at a point in time when a value of d(log|η*|)/dT associated with dissolution of the polyethylene powder first reaches 0.03 or less after passing a peak is regarded as a temperature at which the dissolution of the polyethylene powder is completed, and complex viscosity |η*| at the temperature is |η*|m;
wherein T is measurement temperature
Requirement 3: a value of any peak when d(log|η*|)/dT is plotted against temperature is 1.0 or more and 3.0 or less.