HIGH STRENGTH ULTRA-HIGH MOLECULAR WEIGHT POLYETHYLENE TAPE ARTICLES

• US 20110039058A1
• Filed: 08/11/2009
• Published: 02/17/2011
• Est. Priority Date: 08/11/2009
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Boone, Mark Benjamin, Bhatnagar, Ashok, Tam, Thomas, Correale, Steven
• Granted Patent: US 8,236,119 B2
• Time in Patent Office: Days
• US Class Current: 428/105
• CPC Class Codes: B29C 43/22 of articles of indefinite length
• CPC Class Codes: B29C 55/06 parallel with the direction of feed
• CPC Class Codes: B29C 55/065 in several stretching steps
• CPC Class Codes: B29K 2023/0683 UHMWPE, i.e. ultra high molecular weight polyethylene
• CPC Class Codes: B32B 5/12 characterised by the relative arrangement of fibres or filaments of different layers, e.g. the fibres or filaments being parallel or perpendicular to each other
• CPC Class Codes: C08F 110/02 Ethene
• CPC Class Codes: D03D 1/0052 Antiballistic fabrics
• CPC Class Codes: D03D 13/004 with weave pattern being non-standard or providing special effects
• CPC Class Codes: D04B 1/16 synthetic threads
• CPC Class Codes: D07B 2205/2014 High performance polyolefins, e.g. Dyneema or Spectra
• CPC Class Codes: D07B 2801/10 Smallest filamentary entity of a rope or strand, i.e. wire, filament, fiber or yarn
• CPC Class Codes: F41H 1/02 Armoured or projectile- or missile-resistant garments; Composite protection fabrics F41H5/04 takes precedence
• CPC Class Codes: Y10T 428/24 Structurally defined web or sheet [e.g., overall dimension, etc.]
• CPC Class Codes: Y10T 428/24058 including grain, strips, or filamentary elements in respective layers or components in angular relation
• CPC Class Codes: Y10T 428/24074 Strand or strand-portions
• CPC Class Codes: Y10T 428/24479 including variation in thickness
• CPC Class Codes: Y10T 428/2495 Thickness [relative or absolute]
• CPC Class Codes: Y10T 428/2913 Rod, strand, filament or fiber
• CPC Class Codes: Y10T 442/2623 Ballistic resistant
• CPC Class Codes: Y10T 442/30 Woven fabric [i.e., woven strand or strip material]
• CPC Class Codes: Y10T 442/3041 : Woven fabric comprises strips or ribbons only
• CPC Class Codes: Y10T 442/40 : Knit fabric [i.e., knit strand or strip material]
• CPC Class Codes: Y10T 442/406 : Including parallel strips

Abstract

Processes for the production of high strength polyethylene tape articles from high strength ultra-high molecular weight multi-filament yarns, and to the tape articles, fabrics, laminates and impact resistant materials made therefrom.

Claims

1. A process for the production of a polyethylene tape article comprising:

a) selecting at least one polyethylene multi-filament yam, said yarn having a c-axis orientation function at least 0.96, an intrinsic viscosity when measured in decalin at 135°

C. by ASTM D1601-99 of from about 7 dl/g to about 40 dl/g, and said yarn having a tenacity of from about 15 g/d to about 100 g/d as measured by ASTM D2256-02 at a 10 inch (25.4 cm) gauge length and at an extension rate of 100%/min;

b) placing said yarn under a longitudinal tensile force and subjecting said yarn to at least one transverse compression step to flatten, consolidate and compress said yarn at a temperature of from about 25°

C. to about 137°

C., thereby forming a tape article having a average cross-sectional aspect ratio at least about 10;

1, each said compression step having an outset and a conclusion wherein the magnitude of said longitudinal tensile force on each said yarn or tape article at the outset of each said compression step is substantially equal to the magnitude of the longitudinal tensile force on the yarn or tape article at the conclusion of that same compression step, and is at least about 0.25 kilogram-force (2.45 Newtons);

c) stretching said tape article at least once at a temperature in the range of from about 130°

C. to about 160°

C. at a stretch rate of from about 0.001 min<sup>−

1</sup> to about 1 min<sup>−

1</sup>;

d) optionally repeating step b) one or more times at a temperature from about 100°

C. to about 160°

C.;

e) optionally repeating step c) one or more times;

f) optionally relaxing the longitudinal tensile force between any of steps b) to e);

g) optionally increasing the longitudinal tensile force between any of steps b) to e);

h) cooling said tape article to a temperature less than about 70°

C. under tension.

2. The process of claim 1 wherein steps b) through h) are performed continuously.

3. The process of claim 1 wherein the selected multi-filament yarn has less than about 10 turns of twist per inch (2.54 cm) of length.

4. The process of claim 1 wherein the filaments of the selected multi-filament yarn have been connected by means of a process selected from the group consisting of fusion and bonding.

5. The process of claim 1, wherein the strength of the tape article measured by ASTM D882-09 at a 10 inch (25.4 cm) gauge length and at an extension rate of 100%/min, is at least 75% of the strength of the multi-filament yarn from which it was produced.

6. The process of claim 1, wherein when measured by ASTM D882-09 at a 10 inch (25.4 cm) gauge length and at an extension rate of 100%/min, said tape article has a tensile strength at least about 2.2 GPa.

7. The process of claim 1 wherein a means for compression is vibrated in a direction relative to the plane of a tape article selected from the group consisting of normal to said plane, in said plane, and inclined to both said planes.

8. A process for the production of a polyethylene tape article comprising:

a) selecting at least one polyethylene multifilament yarn, said yarn having a c-axis orientation function at least 0.96, an intrinsic viscosity when measured in decalin at 135°

C. by ASTM D1601-99 of from about 7 dl/g to about 40 dl/g, said yarn having a tenacity of from about 15 g/d to about 100 g/d as measured by ASTM D2256-02 at 10 inch (25.4 cm) gauge length and at an extension rate of 100%/min;

b) passing said yarn continuously through one or more heated zones at temperatures of from about 100°

C. to about 160°

C. under tension;

c) stretching said heated yarn at least once at a stretch rate of from about 0.01 min<sup>−

1</sup> to about 5 min<sup>−

1</sup>;

d) placing said yarn under a longitudinal tensile force and subjecting said yarn to at least one transverse compression step to flatten, consolidate and compress said yarn at a temperature of from about 100°

C. to about 160°

C., thereby forming a tape article having a average cross-sectional aspect ratio at least about 10;

1, each said compression step having an outset and a conclusion wherein the magnitude of said longitudinal tensile force on each said yarn or tape article at the outset of each said compression step is substantially equal to the magnitude of the longitudinal tensile force on the yarn or tape article at the conclusion of that same compression step, and is at least about 0.25 kilogram-force (2.45 Newtons);

e) stretching said tape article at least once at a temperature of from about 130°

C. to about 160°

C. at a stretch rate of from about 0.001 min<sup>−

1</sup> to about 1 min<sup>−

1</sup>;

f) optionally repeating step d) one or more times;

g) optionally repeating step e) one or more times;

h) optionally relaxing the longitudinal tensile force between any of steps c) to g);

i) optionally increasing the longitudinal tensile force between any of steps c) to g);

j) cooling said tape article to a temperature less than about 70°

C. under tension.

9. The process of claim 8 wherein steps b) though j) are performed continuously.

10. The process of claim 8 wherein the selected multi-filament yarn has from 0 to about 10 turns of twist per inch (2.54 cm) of length.

11. The process of claim 8 wherein the filaments of the selected multi-filament yarn have been connected by means of a process selected from the group consisting of fusion and bonding.

12. The process of claim 8, wherein the strength of the tape article measured by ASTM D882-09 at a 10 inch (25.4 cm) gauge length and at an extension rate of 100%/min, is at least 75% of the strength of the multi-filament yarn from which it was produced.

13. The process of claim 8 wherein when measured by ASTM D882-09 at a 10 inch (25.4 cm) gauge length and at an extension rate of 100%/min, said tape article has a tensile strength at least about 2.2 GPa.

14. The process of claim 8 wherein when measured by ASTM D882-09 at a 10 inch (25.4 cm) gauge length and at an extension rate of 100%/min, said tape article has a tensile strength at least about 3.0 GPa.

15. The process of claim 8 wherein a means for compression is vibrated in a direction relative to the plane of a tape article selected from the group consisting of normal to said plane, in said plane, and inclined to both said planes.

16. A polyethylene tape article of an average cross-sectional aspect ratio at least about 10:

1, said polyethylene having an intrinsic viscosity when measured in decalin at 135°

C. by ASTM D1601-99 of from about 7 dl/g to 40 dl/g, and when measured by ASTM D882-09 at a 10 inch (25.4 cm) gauge length and at an extension rate of 100%/min, said tape article having a tensile strength at least about 3.6 GPa.

17. A fabric comprising tape articles as described in claim 16, said fabric being selected from the group consisting of woven, knitted and three dimensionally woven.

18. A laminate comprising two or more unidirectional layers of the tape articles as described in claim 16 with the tape direction in adjoining layers being rotated from each other by from about 15 to about 90 degrees.

19. An impact and penetration resistant assembly comprising at least one member selected from the group consisting of a fabric as described in claim 17.

20. The assembly of claim 19 having an areal density at least 1.5 Kg/m² and a specific energy absorption of at least 500 J-m²/Kg at the V50 velocity as measured against a 9 by 19 mm FMJ Parabellum bullet by MIL.STD.662F.