摘要:
A method for stretch breaking fibers to produce a staple yarn and operating a staple fiber spinning machine, and an apparatus for performing such method, that enables the production of a plurality of products of lot size smaller than a large denier tow product. The process includes at least two break zones and a consolidation zone downstream from a second break zone to form a staple yarn. The filaments are broken in a second break zone downstream from the first break zone by increasing the speed of the fiber fed into the process.
摘要:
A method for stretch breaking fibers to produce a staple yarn and operating a staple fiber spinning machine that enables the production of a plurality of products of lot size smaller than a large denier tow product. The process includes at least two break zones and a consolidation zone downstream from a second break zone to form a staple yarn. The filaments are broken in a second break zone downstream from the first break zone by increasing the speed of the fiber fed into the process.
摘要:
A nanoweb that contains a plurality of nanofibers wherein the nanofibers contain a fully aromatic polyimide that is characterized by having a crystallinity index (CI) and a degree of imidization (DOI). The product of the DOI and the CI is between 0.08 and 0.25 or above a lower limit to obtain a desired tensile strength and/or toughness. The nanoweb may for example have a tensile strength per unit basis weight of greater than 15 kg/cm2 per gram per square meter unit of basis weight.
摘要翻译:纳米纤维网包含多个纳米纤维,其中纳米纤维含有完全芳族聚酰亚胺,其特征在于具有结晶度指数(CI)和酰亚胺化程度(DOI)。 DOI和CI的产物在0.08至0.25之间或更高于下限以获得所需的拉伸强度和/或韧性。 纳米纤维可以例如每单位面积重量的抗拉强度大于15kg / cm 2 /克/平方米单位单位面积重量。
摘要:
The invention provides a process comprising heating a polyamic acid fiber to a temperature in the range of a first temperature and a second temperature for a period of time in the range of 5 seconds to 5 minutes to form a polyimide fiber, wherein the first temperature is the imidization temperature of the polyamic acid and the second temperature is the decomposition temperature of the polyimide
摘要:
This invention provides a multi-layer article comprising a first electrode material, a second electrode material, and a porous separator disposed between and in contact with the first and the second electrode materials, wherein the porous separator comprises a nanoweb consisting essentially of a plurality of nanofibers of a fully aromatic polyimide. Also provided is a method for preparing the multi-layer article, and an electrochemical cell employing the same. A multi-layer article comprising a polyimide nanoweb with enhanced properties is also provided.
摘要:
A bag filter having a support structure clothed in a filter bag. The cloth of the filter bag is a composite of at least one substrate layer and at least one nanoweb bonded thereto in a face-to-face relationship. The nanoweb is positioned at the surface of the filter bag first exposed to the hot particle laden gas stream and can have a basis weight of greater than about 2 gsm.
摘要:
This invention provides an electrochemical cell comprising a housing having disposed therewithin, an electrolyte, and a multi-layer article at least partially immersed in the electrolyte; the multi-layer article comprising a first metallic current collector, a first electrode material in electrically conductive contact with the first metallic current collector, a second electrode material in ionically conductive contact with the first electrode material, a porous separator disposed between and contacting the first electrode material and the second electrode material; and, a second metallic current collector in electrically conductive contact with the second electrode material, wherein the porous separator comprises a nanoweb consisting essentially of a plurality of nanofibers of a fully aromatic polyimide. Also provided is a process for preparing the multi-layer article. Further provided is an electrochemical cell wherein the separator is a polyimide nanoweb with enhanced properties.
摘要:
A composite sheet of a nanoweb bonded to a second web, such that fibers from the second web protrude through the nanoweb in a multiplicity of discontinuous regions.
摘要:
A bag filter having a support structure clothed in a filter bag. The cloth of the filter bag is a composite of at least one substrate layer and at least one nanoweb bonded thereto in a face-to-face relationship. The nanoweb is positioned at the surface of the filter bag first exposed to the hot particle laden gas stream and can have a basis weight of greater than about 2 gsm.
摘要:
The invention provides a method for enhancing the properties of polyimide nanowebs, the method comprising subjecting a nanoweb consisting essentially of a plurality of nanofibers of an aromatic polyimide to a temperature at least 50 C.° higher than the imidization temperature thereof for a period of time in the range of 5 seconds to 20 minutes, thereby preparing an enhanced nanoweb. Also provided is a multi-layer article comprising the enhanced nanoweb, and an electrochemical cell comprising the multi-layer article.