ULTRA-HIGH STRENGTH UHMW PE FIBERS AND PRODUCTS

• US 20110266710A1
• Filed: 04/30/2010
• Published: 11/03/2011
• Est. Priority Date: 06/08/2007
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: TAM, THOMAS Y., Young, John A., Hermes, John E., Aminuddin, Norman
• Granted Patent: US 8,747,715 B2
• Time in Patent Office: Days
• US Class Current: 264/210.7
• CPC Class Codes: B29C 48/05 Filamentary, e.g. strands
• CPC Class Codes: B29C 48/832 Heating
• CPC Class Codes: B29C 48/90 with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article
• CPC Class Codes: B29C 48/906 using roller calibration
• CPC Class Codes: B29C 48/91 Heating, e.g. for cross linking
• CPC Class Codes: B29C 48/919 using a bath, e.g. extruding into an open bath to coagulate or cool the material
• CPC Class Codes: D01D 1/02 Preparation of spinning solutions
• CPC Class Codes: D01D 5/06 Wet spinning methods D01D5/0046 takes precedence
• CPC Class Codes: D01D 5/098 with simultaneous stretching
• CPC Class Codes: D01D 5/12 Stretch-spinning methods D01D5/098 takes precedence finishing by stretching D02J1/22
• CPC Class Codes: D01F 6/04 from polyolefins
• CPC Class Codes: F41H 5/02 Plate construction
• CPC Class Codes: F41H 5/0485 all the layers being only fibre- or fabric-reinforced layers

Abstract

Multi-filament UHMW PE yarns can be produced according to processes that result in improved properties. The UHMW PE can have an intrinsic viscosity in decalin at 135° C. of at least about 30 dl/g, and can be processed under optimal conditions to achieve a gel spun yarn having a tenacity of greater than about 45 g/d (40.5 g/dtex).

Claims

1. A processes for producing gel spun yarn made from ultra high molecular weight polyethylene (UHMW PE), the process comprising the steps of:

feeding a slurry that comprises an UHMW PE and a spinning solvent to an extruder to produce a liquid mixture, the UHMW PE having an intrinsic viscosity in decalin at 135°

C. of at least about 30 dl/g;

passing the liquid mixture through a heated vessel to form a homogeneous solution comprising the UHMW PE and the spinning solvent;

providing the solution from the heated vessel to a spinneret to form a solution yarn;

drawing the solution yarn that issues from the spinneret at a draw ratio of from about 1.1;

1 to about 30;

1 to form a drawn solution yarn;

cooling the drawn solution yarn to a temperature below the gel point of the UHMW PE polymer to form a gel yarn;

drawing the gel yarn in one or more stages at a first draw ratio DR1 of from about 1.1;

1 to about 30;

1;

drawing the gel yarn at a second draw ratio DR2;

removing spinning solvent from the gel yarn in a solvent removal device to form a dry yarn;

drawing the dry yarn at a third draw ratio DR3 in at least one stage to form a partially oriented yarn;

transferring the partially oriented yarn to a post drawing operation; and

drawing the partially oriented yarn at a post drawing temperature in the post drawing operation to a fourth draw ratio DR4 of from about 1.8;

1 to about 15;

1 to form a highly oriented yarn product having a tenacity of greater than about 45 g/d (40.5 g/dtex) and a modulus of greater than about 1400 g/d.

2. The processes for producing gel spun yarn of claim 1, wherein the partially oriented yarn is produced in a continuous in-line process and the post drawing operation is a discontinuous step that is separate from the in-line process.

3. The processes for producing gel spun yarn of claim 1, wherein the UHMW PE has average particles size from 100 microns to about 200 microns and about 90% of the particles have a particle size that is within 40 microns of the average particle size.

4. The processes for producing gel spun yarn of claim 3, wherein the UHMW PE has an intrinsic viscosity of greater than about 30 dl/g, and the partially oriented yarn has an intrinsic viscosity of greater than about 17 dl/g.

5. The processes for producing gel spun yarn of claim 1, wherein the highly oriented yarn product has an intrinsic viscosity that is from about 0.2 times the intrinsic viscosity of the UHMW PE to about 0.65 times the intrinsic viscosity of the UHMW PE polymer.

6. The processes for producing gel spun yarn of claim 1, wherein the solution comprises the UHMW PE in an amount from about 6% by weight to about 10% by weight of the solution.

7. The processes for producing gel spun yarn of claim 1, wherein the spinning solvent is selected from the group consisting of halogenated hydrocarbons, mineral oil, decalin, tetralin, naphthalene, xylene, tolune, dodecane, undecane, decane, nonane, octene, cis-decahydronaphthalene, trans-decahydronaphthalene, low molecular weight polyethylene wax, and mixtures thereof.

8. The processes for producing gel spun yarn of claim 7, wherein the spinning solvent is selected from the group consisting of mineral oil, decalin, and mixtures thereof.

9. The processes for producing gel spun yarn of claim 1, wherein the partially oriented yarn (POY) has a tenacity from about 12 g/d (10.8 g/dtex) to about 25 g/d (22.5 g/dtex).

10. The processes for producing gel spun yarn of claim 1, wherein the post drawing temperature of the post drawing operation is from about 125°

C. to about 160°

C.

11. The processes for producing gel spun yarn of claim 1, wherein the drawing rate of the drawing of the post drawing operation is a constant value when the partially oriented yarn is at the post drawing temperature.

12. The processes for producing gel spun yarn of claim 1, wherein the drawing profile of the post drawing operation is a straight line when the partially oriented yarn is at the post drawing temperature.

13. The processes for producing gel spun yarn of claim 1, wherein the drawing of the post drawing operation is conducted in a heating apparatus comprising one or more intermediate rolls over which the partially oriented yarn is passed.

14. A ballistic article made from a gel spun yarn produced in accordance with the processes for producing gel spun yarn of claim 1.

19. The processes for producing gel spun yarn of claim 1, wherein the drawing rate of the drawing of the post drawing operation is a constant value when the partially oriented yarn is at the post drawing temperature.

20. The processes for producing gel spun yarn of claim 1, wherein the drawing, profile of the post drawing operation is a straight line when the partially oriented yarn is at the post drawing temperature.

15. A processes for producing gel spun yarn made from ultra high molecular weight polyethylene (UHMW PE), the process comprising the steps of:

feeding a slurry that comprises an UHMW PE and a spinning solvent to an extruder to produce a liquid mixture, the UHMW PE having an average particle size from about 100 microns to about 200 microns and an intrinsic viscosity in decalin at 135°

C. of at least about 30 dl/g;

passing the liquid mixture through a heated vessel having a temperature from about 220°

C. to about 320°

C. to form a homogeneous solution comprising the UHMW PE and the spinning solvent, the solution including UHME PE in an amount from about 5% by weight to about 20% by weight of the solution;

providing the solution from the heated vessel to a spinneret to form a solution yarn;

drawing the solution yarn that issues from the spinneret at a draw ratio of from about 1.1;

1 to about 30;

1 to form a drawn solution yarn;

cooling the drawn solution yarn to a temperature below the gel point of the UHMW PE polymer to form a gel yarn;

drawing the gel yarn in one or more stages at a first draw ratio DR1 of from about 1.1;

1 to about 30;

1;

drawing the gel yarn at a second draw ratio DR2;

removing spinning solvent from the gel yarn in a solvent removal device to form a dry yarn;

drawing the dry yarn at a third draw ratio DR3 in at least one stage to form a partially oriented yarn, the partially oriented yarn having an intrinsic viscosity of greater than about 19 dl/g;

transferring the partially oriented yarn to a post drawing operation; and

drawing the partially oriented yarn at a post drawing temperature in the post drawing operation to a fourth draw ratio DR4 of from about 1.8;

1 to about 15;

1 to form a highly oriented yarn product having a tenacity of greater than about 45 g/d (40.5 g/dtex) and a modulus of greater than about 1400 g/d.

16. The processes for producing gel spun yarn of claim 15, wherein the partially oriented yarn is produced in a continuous in-line process and the post drawing operation is a discontinuous step that is separate from the in-line process.

17. The processes for producing gel spun yarn of claim 15, wherein the highly oriented yarn product has an intrinsic viscosity that is from about 0.2 times the intrinsic viscosity of the UHMW PE to about 0.65 times the intrinsic viscosity of the UHMW PE polymer.

18. The processes for producing gel spun yarn of claim 15, wherein the solution comprises the UHMW PE in an amount from about 6% by weight to about 10% by weight of the solution.