Abstract: Gel-spun multi-filament polyethylene yarns possessing a high degree of molecular and crystalline order, and to the drawing methods by which they are produced. The drawn yarns are useful in impact absorption and ballistic resistance for body armor, helmets, breast plates, helicopter seats, spall shields, and other applications; composite sports equipment such as kayaks, canoes, bicycles and boats; and in fishing line, sails, ropes, sutures and fabrics.

Abstract: Apparatus and method are described for measuring and controlling the crimp characteristics of a moving crimped tow. A light source illuminates a section of the moving crimped tow and at least one progressive scanning camera acquires a non-interlaced video image of the tow. The acquired image is digitized and a processor analyzes the non-interlaced image. Crimp characteristics are derived based on this analysis.

Abstract: A composition comprises a solid-stated block copolymer of an aromatic polyester and a caprolactone, wherein the copolymer has been solid state polymerized such that intrinsic viscosity increases at least 20%, the caprolactone content decreases no more than 1.2% absolute and the transesterification increases no more than 3.5% absolute, and wherein the solid-stated copolymer has an intrinsic viscosity of at least 0.82. Particularly preferred chain extension reactions are performed at a temperature of less than 175° C., and even more preferably at less than 165° C. In further aspects of the inventive subject matter, yarns and methods of producing a fiber include contemplated solid-stated block copolymers.

Abstract: A yarn having good entanglement and good quality, preferably a multifilament polyamide yarn, a method for making the yarn, and a woven fabric made from the yarn wherein the yarn comprises the following properties: the yarn length per defect is greater than or equal to about 3000 meters per defect; the maximum skip length is less than or equal to about 120 millimeters; the ratio between yarn length per defect to maximum skip length is greater than or equal to about 50; the entanglements per meter times the average entanglement strength is greater than or equal to about 120; and the yarn can be woven sizeless. The yarn of the invention is useful in the sizeless weaving of fabric used in air bags.

Abstract: A composition comprises a solid-stated block copolymer of an aromatic polyester and a caprolactone, wherein the copolymer has been solid state polymerized such that intrinsic viscosity increases at least 20%, the caprolactone content decreases no more than 1.2% absolute and the transesterification increases no more than 3.5% absolute, and wherein the solid-stated copolymer has an intrinsic viscosity of at least 0.82. Particularly preferred chain extension reactions are performed at a temperature of less than 175° C., and even more preferably at less than 165° C. In further aspects of the inventive subject matter, yarns and methods of producing a fiber include contemplated solid-stated block copolymers.

Abstract: Apparatus and method are described for measuring and controlling the crimp characteristics of a moving crimped tow. A light source illuminates a section of the moving crimped tow and at least one progressive scanning camera acquires a non-interlaced video image of the tow. The acquired image is digitized and a processor analyzes the non-interlaced image. Crimp characteristics are derived based on this analysis.

Abstract: A yarn having good entanglement and good quality, preferably a multifilament polyamide yarn, a method for making the yarn, and a woven fabric made from the yarn wherein the yarn comprises the following properties: the yarn length per defect is greater than or equal to about 3000 meters per defect; the maximum skip length is less than or equal to about 120 millimeters; the ratio between yarn length per defect to maximum skip length is greater than or equal to about 50; the entanglements per meter times the average entanglement strength is greater than or equal to about 120; and the yarn can be woven sizeless. The yarn of the invention is useful in the sizeless weaving of fabric used in air bags.

Abstract: A yarn having good entanglement and good quality, preferably a multifilament polyamide yarn, a method for making the yarn, and a woven fabric made from the yarn wherein the yarn comprises the following properties: the yarn length per defect is greater than or equal to about 3000 meters per defect; the maximum skip length is less than or equal to about 120 millimeters; the ratio between yarn length per defect to maximum skip length is greater than or equal to about 50; the entanglements per meter times the average entanglement strength is greater than or equal to about 120; and the yarn can be woven sizeless. The yarn of the invention is useful in the sizeless weaving of fabric used in air bags.

Abstract: A yarn having good entanglement and good quality, preferably a multifilament polyamide yarn, a method for making the yarn, and a woven fabric made from the yarn wherein the yarn comprises the following properties: the yarn length per defect is greater than or equal to about 3000 meters per defect; the maximum skip length is less than or equal to about 120 millimeters; the ratio between yarn length per defect to maximum skip length is greater than or equal to about 50; the entanglements per meter times the average entanglement strength is greater than or equal to about 120; and the yarn can be woven sizeless. The yarn of the invention is useful in the sizeless weaving of fabric used in air bags.

Abstract: Apparatus and method are described for measuring and controlling the crimp characteristics of a moving crimped tow. A light source illuminates a section of the moving crimped tow and at least one camera acquires a video image of the tow. The acquired image is digitized and a processor decomposes the interlaced image into two non-interlaced field images. Crimp characteristics are derived based on the decomposed images.

Abstract: By poststretching, at a temperature between about 135.degree. and 160.degree. C., a polyethylene fiber, which has already been oriented by drawing at a temperature within 5.degree. C. of its melting point, an ultra high modulus, very low creep, low shrink, high tenacity polyolefin fiber having good strength retention at high temperatures is obtained. The poststretching can be in multiple stages and/or with previous annealing. The poststretching should be done at a draw rate of less than 1 second.sup.-1. Tensile modulus values over 2,000 g/d for multifilament yarn are consistently obtained for ultrahigh molecular weight polyethylene, with tensile strength values above 30 g/d while at the same time dramatically improving creep (at 160.degree. F. (71.1.degree. C.) and 39,150 psi load) by values at least 25% lower than fiber which has not been poststretched. Shrinkage is improved to values less than 2.5% of the original length when heated from room temperature to 135.degree. C.

Abstract: An entangled multifilament yarn made from high strength filaments having a tenacity of at least about 7 g/d, a tensile modulus of at least about 150 g/d and an energy-to-break of at least about 8 J/g. The yarn is used to make ballistic resistant articles.

Abstract: By poststretching, at a temperature between about 135.degree. and 160.degree. C., a polyethylene fiber, which has already been oriented by drawing at a temperature within 5.degree. C. of its melting point, an ultra high modulus, very low creep, low shrink, high tenacity polyolefin fiber having good strength retention at high temperatures is obtained. The poststretching can be in multiple stages and/or with previous annealing. The poststretching should be done at a draw rate of less than 1 second.sup.-1. Tensile modulus values over 2,000 g/d for multifilament yarn are consistently obtained for ultrahigh molecular weight polyethylene, with tensile strength values above 30 g/d while at the same time dramatically improving creep (at 160.degree. F. (71.1.degree. C.) and 39,150 psi load) by values at least 25% lower than fiber which has not been poststretched. Shrinkage is improved to values less than 2.5% of the original length when heated from room temperature to 135.degree. C.