Ultra-high molecular weight polyethylene fiber

• US 10,640,585 B2
• Filed: 11/09/2018
• Issued: 05/05/2020
• Est. Priority Date: 11/15/2017
• Status: Active Grant

• Current Assignee: Asahi Kasei Kabushiki Kaisha (Asahi Kasei Corporation)
• Original Assignee: Asahi Kasei Kabushiki Kaisha (Asahi Kasei Corporation)
• Inventors: Tsujimoto, Koichi
• Primary Examiner(s): Choi, Ling Siu
• Assistant Examiner(s): Grinsted, Ronald
• Application Number:
  US16/185,330
• Publication Number:
  US 20190153128A1
• Time in Patent Office: 543 Days
• Field of Search: 526352
• CPC Class Codes: C08F 10/02 Ethene
• CPC Class Codes: C08F 110/02 Ethene
• CPC Class Codes: C08F 2410/06 Catalyst characterized by its size
• CPC Class Codes: C08F 2420/02 Cp or analog bridged to a non-Cp X anionic donor
• CPC Class Codes: C08F 2500/01 High molecular weight, e.g. >800,000 Da.
• CPC Class Codes: C08F 2500/04 Broad molecular weight distribution, i.e. Mw/Mn > 6
• CPC Class Codes: C08F 4/6555 and magnesium or compounds thereof
• CPC Class Codes: C08F 4/65908 in combination with an ionising compound other than alumoxane, e.g. (C6F5)4B-X+
• CPC Class Codes: C08F 4/65912 in combination with an organoaluminium compound
• CPC Class Codes: C08F 4/65916 supported on a carrier, e.g. silica, MgCl2, polymer
• CPC Class Codes: C08F 4/6592 containing at least one cyclopentadienyl ring, condensed or not, e.g. an indenyl or a fluorenyl ring
• CPC Class Codes: D01D 1/02 Preparation of spinning solutions
• CPC Class Codes: D01F 6/04 from polyolefins

Abstract

The present invention provides an ultra-high molecular weight polyethylene fiber having a viscosity-average molecular weight of 10×10⁴ to 1000×10⁴, wherein the ultra-high molecular weight polyethylene fiber has at least three melting peaks in a heating differential scanning calorimetry curve (DSC curve), and in the melting peaks, the difference between (I) a peak temperature of a melting peak appearing between 140° C. or higher and lower than 150° C. and (II) a peak temperature of a melting peak appearing between 150° C. or higher and lower than 158° C. is 10° C. or less.

Claims

1. An ultra-high molecular weight polyethylene fiber having a viscosity-average molecular weight of 10×

10⁴ to 1000×

10⁴, wherein

the ultra-high molecular weight polyethylene fiber has at least three melting peaks in a heating differential scanning calorimetry curve, and

in the melting peaks, the difference between (I) a peak temperature of a melting peak appearing between 140°

C. or higher and lower than 150°

C. and (II) a peak temperature of a melting peak appearing between 150°

C. or higher and lower than 158°

C. is 10°

C. or less,

a ratio of an area (Δ

H₂) at or below (I) a peak temperature of a melting peak appearing between 140°

C. or higher and lower than 150°

C. to an area (Δ

H₁) of a whole melting peak is 15% or more and 35% or less, and

a ratio of an area (Δ

H₃) at or above (III) a peak temperature of a melting peak appearing between 158°

C. or higher and 170°

C. or lower to the area (Δ

H₁) of the whole melting peak is 5% or more and 10% or less.

2. The ultra-high molecular weight polyethylene fiber according to claim 1, wherein the ultra-high molecular weight polyethylene fiber has a degree of orientation of 0.40 or more.

3. The ultra-high molecular weight polyethylene fiber according to claim 1, comprising a copolymer of ethylene and a comonomer, wherein a content of a comonomer unit in the copolymer is 0.01% by mol or more and 5% by mol or less.

4. The ultra-high molecular weight polyethylene fiber according to claim 1, wherein the ultra-high molecular weight polyethylene fiber has a titanium content of 5 ppm or lower.

5. The ultra-high molecular weight polyethylene fiber according to claim 1, wherein the ultra-high molecular weight polyethylene fiber has a silicon content of 0.1 ppm or higher and 50 ppm or lower.

6. The ultra-high molecular weight polyethylene fiber according to claim 1, wherein the ultra-high molecular weight polyethylene fiber has Mw/Mn of 3.0 or more and 13 or less.

7. The ultra-high molecular weight polyethylene fiber according to claim 1, wherein the ultra-high molecular weight polyethylene fiber has an ash content of 100 ppm or lower.

8. The ultra-high molecular weight polyethylene fiber according to claim 1, wherein the ultra-high molecular weight polyethylene fiber has a creep life of at least 72 hours at a temperature of 70°

C. under 30% load of breaking stress.