摘要:
Disclosed is a method of forming multifilament polyolefin yarns and yarns formed according to the disclosed method. The yarns can be polypropylene yarns and can exhibit any of a high modulus, high tenacity, and a unique crystalline structure for multifilament polyolefin yarns. The process can generally include extruding a polymeric melt including the polyolefin at a relatively high throughput and low spinline tension and quenching the filaments in a liquid bath prior to drawing the fiber bundle at a relatively high draw ratio, for example greater than 10, in some embodiments.
摘要:
A textile fabric wiper is provided having a polymer coating applied to enhance the attraction of the wiper to particulate contaminants, especially particles in the range of 0.5 to 20 microns.
摘要:
Improvements in preventing heat- and moisture-shrink problems in specific polypropylene tape fibers are provided. Such fibers are basically manufactured through the initial production of polypropylene films or tubes which are then slit into very thin, though flat (and having very high cross sectional aspect ratios) tape fibers thereafter. Such fibers (and thus the initial films and/or tubes) require the presence of certain compounds that quickly and effectively provide rigidity to the target polypropylene tape fiber after heat-setting. Generally, these compounds include any structure that nucleates polymer crystals within the target polypropylene after exposure to sufficient heat to melt the initial pelletized polymer and upon allowing such a melt to cool. The compounds must nucleate polymer crystals at a higher temperature than the target polypropylene without the nucleating agent during cooling. In such a manner, the “rigidifying” nucleator compounds provide nucleation sites for polypropylene crystal growth. Upon slitting of the initial film and/or tube, the fiber is then exposed to sufficient heat to grow the crystalline network, thus holding the fiber in a desired position. The preferred “rigidifying” compounds include dibenzylidene sorbitol based compounds, as well as less preferred compounds, such as sodium benzoate, certain sodium and lithium phosphate salts (such as sodium 2,2′-methylene-bis-(4,6-di-tert-butylphenyl)phosphate, otherwise known as NA-11). Specific methods of manufacture of such inventive tape fibers, as well as fabric articles made therefrom, are also encompassed within this invention.
摘要:
Improvements in permitting brighter colorations within polypropylene fibers and/or yarns while simultaneously providing more efficient production methods of manufacturing of such colored fibers as well are provided. Generally, such fibers and/or yarns have been colored with pigments, which exhibit dulled results, or dyes, which exhibit high degrees of extraction and low levels of lightfastness. Such dull appearances, high extraction levels, and less than stellar lightfastness properties negatively impact the provision of such desirable colored polypropylene fibers and/or yarns which, in turn, prevents the widespread utilization of such fibers and yarns in various end-use applications. Thus, it has surprisingly been determined that brighter colorations, excellent extraction, and more-than-acceptable lightfastness characteristics can be provided, preferably, through manufacture with certain polymeric colorants that include poly(oxyalkylene) groups thereon. Fabric articles comprising such novel fibers and/or yarns are also encompassed within this invention.
摘要:
Disclosed is a method of forming multifilament polyolefin yarns and yarns formed according to the disclosed method. The yarns can be polypropylene yarns and can exhibit any of a high modulus, high tenacity, and a unique crystalline structure for multifilament polyolefin yarns. The process can generally include extruding a polymeric melt including the polyolefin at a relatively high throughput and low spinline tension and quenching the filaments in a liquid bath prior to drawing the fiber bundle at a relatively high draw ratio, for example greater than 10, in some embodiments.
摘要:
Disclosed are composite laminates that can exhibit high strength and/or low dielectric loss and can also be lightweight. The laminates include layers formed of high modulus polyolefin fiber. The fibers can be woven or knit to form a fabric or can be included in a nonwoven fabric that can be one or more layers of the composite structures. The layers including the high modulus polyolefin fibers can include other fibers, such as fiberglass. The composites can also include layers of other materials, for instance layers formed of polyaramids, fiberglass, or carbon fiber wovens or nonwovens. The composites can advantageously be utilized in low loss dielectric applications, such as in forming circuit board substrates, or in applications beneficially combining strength with low weight, such as automobile and boat materials.
摘要:
Disclosed are composite laminates that can exhibit high strength and/or low dielectric loss and can also be lightweight. The laminates include layers formed of high modulus polyolefin fiber. The fibers can be woven or knit to form a fabric or can be included in a nonwoven fabric that can be one or more layers of the composite structures. The layers including the high modulus polyolefin fibers can include other fibers, such as fiberglass. The composites can also include layers of other materials, for instance layers formed of polyaramids, fiberglass, or carbon fiber wovens or nonwovens. The composites can advantageously be utilized in low loss dielectric applications, such as in forming circuit board substrates, or in applications beneficially combining strength with low weight, such as automobile and boat materials.
摘要:
Resources are partitioned via a virtual partitioning system to distribute the resources over a plurality of resource servers. A virtual partition table can be kept at each of a set of resource managers handling requests for resources in tandem. When a resource is requested, a virtual partition value is calculated algorithmically, and the value is mapped to a resource component via the virtual partition table. The resource component encapsulates information indicating on which of the resource servers the resource resides and can provide a component for performing operations on the resource even though the requester does not have information about where the resource resides. The resources can be repartitioned by modifying the virtual partition table, thus allowing the addition of additional resource servers to the system while the resources remain available. Additional resource types can be added without reengineering the system.
摘要:
Disclosed are composite laminates that can exhibit high strength and/or low dielectric loss and can also be lightweight. The laminates include layers formed of high modulus polyolefin fiber. The fibers can be woven or knit to form a fabric or can be included in a nonwoven fabric that can be one or more layers of the composite structures. The layers including the high modulus polyolefin fibers can include other fibers, such as fiberglass. The composites can also include layers of other materials, for instance layers formed of polyaramids, fiberglass, or carbon fiber wovens or nonwovens. The composites can advantageously be utilized in low loss dielectric applications, such as in forming circuit board substrates, or in applications beneficially combining strength with low weight, such as automobile and boat materials.
摘要:
Disclosed are structural materials including polymeric reinforcment fibers that can provide added strength and fracture toughness to the matrix. The polymeric reinforcement fibers are polypropylene-based monofilament fibers or tape fibers exhibiting extremely favorable mechanical characteristics for structural reinforcement including modulus greater than 12 MPa and elongation less than about 10%. The disclosed reinforced composite materials can exhibit desired average residual strength values with less total fiber loading necessary to attain the ARS values as compared to previously known polymer reinforced materials. Very high strength and fracture toughness can be attained in the disclosed composite materials.