High tenacity, high modulus filament

• US 6,746,975 B2
• Filed: 06/18/2002
• Issued: 06/08/2004
• Est. Priority Date: 03/27/2000
• Status: Expired due to Term

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Kavesh, Sheldon
• Primary Examiner(s): Cheung, William K.
• Application Number:
  US10/174,353
• Publication Number:
  US 20030033655A1
• Time in Patent Office: 721 Days
• Field of Search: 442/135, 442/263, 442/347, 442/353, 442/213
• US Class Current: 442/135
• CPC Class Codes: D01D 4/02 Spinnerettes alloys therefor C22C
• CPC Class Codes: D01F 6/04 from polyolefins
• CPC Class Codes: F41H 5/0471 Layered armour containing fibre- or fabric-reinforced layers in combination with ceramic layers F41H5/0428, with metal layers F41H5/0457
• CPC Class Codes: Y10T 428/2913 Rod, strand, filament or fiber
• CPC Class Codes: Y10T 442/2623 Ballistic resistant
• CPC Class Codes: Y10T 442/3667 Composite consisting of at least two woven fabrics bonded by an interposed adhesive layer [but not two woven fabrics bonded together by an impregnation which penetrates through the thickness of at least one of the woven fabric layers]
• CPC Class Codes: Y10T 442/622 Microfiber is a composite fiber
• CPC Class Codes: Y10T 442/629 Composite strand or fiber material

Abstract

Polyethylene solutions are extruded through a multi-orifice spinneret into a cross-flow gas stream to form a fluid product. The fluid product is stretched at a temperature at which a gel will form at a stretch ratio of at least 5:1 over a length of less than about 25 mm with the cross-flow gas stream velocity at less than about 3 m/min. The fluid product is quenched in a quench bath consisting of an immiscible liquid to form a gel. The gel is stretched. The solvent is removed from the gel to form a xerogel and the xerogel product is stretched in at least two stages to produce a polyethylene yarn characterized by a tenacity of at least 35 g/d, a modulus of at least 1600 g/d and a work to break of at least 65 J/g. The yarn is further characterized by having greater than about 60% of a high strain orthorhombic crystalline component and, optionally, a monoclinic crystalline component greater than about 2% of the crystalline content. Composite panels made with these yarns exhibit excellent ballistic resistance, e.g., SEAC of 300 J-m²/Kg or higher against .38 caliber bullets using test procedure NILECJ-STD-0101.01.

A ballistic resistant composite panel is provided comprising a polyethylene multi-filament yarn having a tenacity of at least about 35 g/d, a modulus of at least 1600 g/d, a work-to-break of at least about 65 J/g wherein the yarn has greater than about 60% of a high strain orthorhombic crystalline component and the yarn has a monoclinic crystalline component greater than about 2% of the crystalline content.

Claims

1. A ballistic resistant composite panel comprising a high strength fiber in a matrix, said panel having an SEAC of at least 466 J-m²/Kg against .38 caliber bullets using test procedure NILECJ-STD-0101.01.

2. The ballistic resistant composite panel of claim 1 wherein the high strength fiber has a tenacity equal to or greater than 45 g/d.

3. The ballistic resistant composite panel of claim 2 wherein the fiber is polyethylene.